Major Report on Energy Mgt

7/30/2019 Major Report on Energy Mgt

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A

PROJECT REPORT

ON

COMPREHENSIVE STUDY ON ENERGY MANAGEMENT

Submitted in the partial fulfillment for the award of degree of

Bachelor of technology

In

ELECTRICAL & ELECTRONICS ENGINEERING

H.C.T.MTECHNICAL

CAMPUS,

KAITHAL

SUBMITTED

TO:-

SUBMITTEDBY:-

Er. VINOD

KUMAR

MANISH

UPPAL

(1709731)

ASSISTANT

PROF.

HIMANSHU

CHANCHAL

(1709742) EEE DEPARTMENT MOHIT GIRDHAR

(1709744)

H.C.T.M TECHNICAL CAMPUS, KAITHAL

KURUKSHETRA UNIVERSITY KURUKSHETRA

CANDIDATE's DECLARATION


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We hereby declare that the work which is being presented in this project entitled "

COMPREHENSIVE STUDY ON ENERGY MANAGEMENT" in partial fulfillment of the

requirement for the award of the degree of bachelor of technology in the field

of Electrical & Electronics Engineering submitted to HCTM TECHNICAL

CAMPUS , Kaithal is an authentic record of my work carried out under the

guidance of Er. Vinod Kumar , Assistant Professor , in the Department of

Electrical & Electronics Engineering , HCTM TECHNICAL CAMPUS , Kaithal .

Date : Manish Uppal (1709731)

Place : Kaithal Himanshu Chanchal ( 1709742)

Mohit Giridhar ( 1709744)

B.Tech. ( Electrical & Electronics

Engineering)

Certificate

This is to certify that the above statement made by the candidate is correct to the best of my

knowledge and belief.

Er. Vinod Kumar Er. Vivek Phawa

Assistant Professor Professor & H.O.D.

Department of Electrical& Department of Electrical&

Electronics Engineering Electronics Engineering

HCTM Technical Campus , Kaithal HCTM Technical Campus , Kaithal

ACKNOWLEDGEMENT


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As the saying goes WE set ourselves to bite the hands that feed us if we fail to

thank such of those to whom our thanks are really due.

In view of the help extended and opportunities given to us to work on

this study based project on "Energy Management" , we are compelled to thank

to all those who took an initiative and helped us in providing input for theproject.

First of all , we consider this an utmost duty to extend our heartiest

thanks to the HOD (EEE Dept) , Mr.Vivek Pahwa for necessary co-operation /

consideration for our successful completion of this project.

Above all we would like to convey our esteemed thanks to Er. Vinod

Kumar , Assistant Professor ( EEE Dept) , for providing necessary guidelines

and nourishing us thorough out with his best experiences in the field of power

system and energy management.

At last but not the least, we would like to extend our thanks to all staff

members and officers of the concerned department of HPSEBL for providing

necessary material for successful completion of the project.

Manish Uppal (1709731)

Himanshu Chanchal ( 1709742)

Mohit Giridhar ( 1709744)

B.Tech. ( Electrical & Electronics

Engineering)


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ABSTRACT

Energy management is a vital issue in the present scenario when the system under

integration mode runs under deficit or surplus conditions. The term energy management

includes planning and operation of energy & its consumption. The application of energy

management is well visualized when an organization receives energy from outside the state

as well as from its own generation within the state. In the modern era, when the energy is

available from renewable energy sources in the pure form and its disposal to the

beneficiaries in the bundled form, uses intensive application of energy management

methodologies.

This study based project is a comprehensive study on Energy Management. Thebasic idea of this project is to get awareness of the energy management methodologies

when some states are surplus in power and some states are deficit in power. Mostly, the

snow fed states like Himachal have less generation during winters and due to melting of

snow during summer, have maximum flow of water in the rivers which ultimately

attributes to enhanced generation during summers. This project also focuses on under

drawal and overdrawal under different frequency conditions under UI regime.

In order to approach step by step hierarchy of energy management, the project has

been divided into two sections. Section-I focuses on role of energy management in power

system and general approach towards energy management methodologies and Section II

is a special case study on energy management in Himachal Pradesh.

Section-I comprises 8 Chapters. The first chapter gives introduction on the

necessity of Energy management when the system is passing through abnormal conditions.

The second chapter stresses the importance of SLDC as an essential tool to energy

management. The third chapter puts light on the very important feature of energy

management i.e. Availability Based Tariff (ABT) , which apprises about the scheduling of

power by the utilities as special feature and importance of ABT in energy management.The

fourth chapter gives knowledge about the role of frequency in energy management under

different frequency conditions.The fifth chapter presents very important aspect of energy

management as to how the energy is managed when deviates from the schedule. The sixth

chapter provides , how the trading opportunities are available both for Generator as well as

Beneficiary under the shadow of energy management.The seventh chapter has its


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importance as without this tool of energy management it is not possible to make trading

with the utilities who are available at some other places. Apart from above , now Indian

Exchange is also one of the players available in the market to take care of disposal /

procurement of power on day to day basis and eighthchapterprovides special features of

power Exchange established in India.

Section-II is very important section which deals with Himachal Pradesh as a special case

of Energy Management and puts light on the tools and methodology being adopted by

Himachal Pradesh for disposal of its surpluses and mitigating deficits.This section

comprises three chapters. The first chapter focuses on status of SLDC in HPSEBL and

second chapter highlights utility of SLDC as an essential tool for energy management.

This provides inputs of different components used in establishing SLDC units , thus gave

an ease to manage energy transactions in effective manners. The third chapter highlights

Himachal Pradesh as a special case of Energy management and provides details of share of

H.P in different sources and modes of energy management .

.


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CONTENTS

SECTION -I

ROLE OF ENERGY MANAGEMENT

IN

POWER SYSTEM OPERATION

CHAPTER 1 INTRODUCTION

1.1 Vital Role of Energy Management

1.2 Basics of Energy Management

1.3 Constraints in Energy Management

CHAPTER 2 SLDC AN ESSENTIAL TOOL TO ENERGY

MANAGEMENT

2.1 Introduction

2.2 Load Dispatch Centers in Northern India

2.3 Real Time Dynamic Security Assessment

CHAPTER 3 AVAILABILITY BASED TARIFF(ABT)

3.1 Introduction

3.2 Details about ABT

3.3 Scheduling

3.3.1 Introduction

3.3.2 Day Ahead Scheduling

3.4 Features of ABT


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CHAPTER 4 ROLE OF FREQUENCY IN ENERGY MANAGEMENT

4.1 Frequency is good and High and the state is overdrawing.

4. 2 Frequency is good and High and the state is Underdrawing.

4.3 Frequency is Low and the state is overdrawing.

4.4 Frequency is Low and the state is Underdrawing.

CHAPTER 5 DEVIATIONS FROM SCHEDULE

5.1 Unscheduled Interchange (UI)

5.2 UI rate determination

5.3 Unscheduled Interchange (UI) Vs Marginal Cost.

CHAPTER 6 A TRADING OPPORTUNITY UNDER THE SHADOW

OF ENERGY MANAGEMENT

6.1 Trading Opportunity to be Availed by the GENERATOR

6.2 Trading Opportunity to be Availed by the BENEFICIARY

CHAPTER 7 OPEN ACCESS , WHEELING AS AN IMPORTANT

TOOL OF ENERGY MANAGEMENT .

7.1 Open Access and Wheeling

7.2 Issues Involved in the Transactions

CHAPTER 8 POWER EXCHANGE IMPLEMENTATION

IN INDIA

8.1 Introduction

8.2 Regulatory Framework for power exchange Implementation

8.3 Power Exchange Implementation in India

8.4 Functional Power Exchange


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8.5 Competition among Exchanges

8.6 Information Exchange between NLDC and Power Exchanges

8.7 Regulations governing the process of Energy Management

SECTION -II

ENERGY MANAGEMENT

IN

HPSEBL

AS

A SPECIAL CASE

CHAPTER 1 STATUS OF SLDC in HPSEBL

0 Setting up SLDC/SUB-LDCs in Himachal Pradesh

1.2 Sub-LDC at Kunihar

1.3 Sub-LDC at Hamirpur

1.4 Interconnectivity of SLDCSUB-LDCs of H.P.


MANAGEMENT

2.1 Introduction

2.2 OPGW and its Installation

2.3 Testing of Optical Fiber Links.

2.4 Monitoring of Status of OPGW

2.5 PLCC System

2.6 PABX System


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2.7 RTU (Remote Terminal Unit)

2.8 UPS (Uninterrupted power supply)

CHAPTER 3 ENERGY MANAGEMENT A "SPECIAL

CASE" OF HIMACHAL PRADESH.

3.1 Introduction

3.2 Grid Diagram of Himachal Pradesh

3.3 Modes for Managing Energy Deficits

3.4 Description Of Different Modes of Energy Management

3.5 HPSEBL Share in different Projects

3.6 STATUS of Energy Managed from different sources in FY 2010-11

3.7 STATUS of Energy Managed different sources in FY 2011-12

Conclusion

Future Scope

References


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LIST OF TABLES

Table No. Description Page

No.

1. HPSEBL Share in different Projects

2. STATUS of Energy Managed in FY 2011-12

3.STATUS of Energy Managed in FY 2012-13


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LIST OF FIGURES

Fig. No. Description Page No.

1. Hierarchical Structure of Load Dispatch Centres in Northern

India.

2. Relationship between UI rate and Grid Frequency

3. Location of SLDC and Sub-LDCs in Himachal Pradesh

4. Hierarchical Structure of SLDC & Sub- LDCs

5. SUB-LDC KUNIHAR (Connectivity of RTUs)

6. SUB-LDC HAMIRPUR (Connectivity of RTUs)

7. Inter Connectivity Diagram Of SLDC , Sub -LDCs of H.P.

8. Combined Connectivity Diagram

9. OPGW (Optical Ground Wire)

10. Types of Fibre Connectors.

11. Test Diagram for Monitoring of Status of OPGW

12. Map of Network Elements of Different Locations

13. Connectivity Between RTU and SUB-LDC Kunihar &Solan

14. PABX Room In SLDC Shimla


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15. Connectivity of PABX Exch. at SLDC with MDF& Console

16. RTU at 132 KV substation Jutogh

17. General Outlook of UPS

18. About Status Of Himachal Pradesh

19. Grid Diagram of Himachal Pradesh

SECTION -I

ROLE OF ENERGY MANAGEMENT

IN

POWER SYSTEM OPERATION


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CHAPTER 1 INTRODUCTION

1.1 Vital Role of Energy Management

Energy management is a vital issue in the present scenario when the system under

integration mode runs under deficit or surplus conditions. The term energy management

includes planning and operation of energy & its consumption. The application of energy

management is well visualized when an organization receives energy from outside the state

as well as from its own generation within the state. In the modern era, when the energy is

available from renewable energy sources in the pure form and its disposal to the

beneficiaries in the bundled form, uses intensive application of energy management

methodologies.

Although, many issues such as energy procurement, disposal, consumption, and itssaving falls under the preview of energy management but this comprehensive study mostly

focuses on the energy management of bulk power procurement under different conditions

such as through nuclear, hydro, thermal based stations, and from REC(Renewable Energy

Certifications).

Energy management study of this project focuses on the status of the states which

have surplus power during summer and deficit power during winter months. Mostly, the

snow fed states have less generation during winters and due to melting of snow during


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summer, have maximum flow of water in the rivers which ultimately attributes to enhanced

generation during summers.

Such states which have surplus power during summer months, their organizations

tie up with the states which have deficit power in summer and provide assistance to these

states to mitigate their shortages by either selling the power or making arrangement under

banking which is one of the important aspects of energy management.

Mostly, the organizations prefer disposal/procurement of power under banking

arrangement as this being considered as cashless transaction. However, even under banking

arrangements also, certain rates are kept so as to settle the accounts on account of

unadjusted quantum, if any, by the end of banking cycle. This project shall mainly focus on

the energy management methodologies being adopted by Himachal State for

disposal/procurement of power under different modes.

1.2 Basics of Energy Management

Most of the states uses following modes for mitigating the shortages of power:

1, By availing free power entitlement of their own states in Central sector / Joint

sector projects .

2. By availing equity power entitlement of their government if any.

3. Through banking arrangements.

4. Unscheduled Interchanges (Over Drawl) transactions under real time operation.

5. Unallocated quota allotted by Govt. of India for deficit months.

In the above stated arrangements, the power from Central Sector Projects is

managed under the guidelines of CERC regulations. This power is initially made available

at generator terminal and is wheeled through Power Grid system to make it available at HP

periphery. Similarly, the free power entitlement of GoHP (Govt. of H.P.) is availed through

traders appointed by the government for this purpose. The banking arrangement is made

with different neighboring utilities. Many states also manages power deficits through

perforce transactions, i.e. under UI (Unscheduled Interchange) arrangements.

0 a. Central Sector Projects:


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Utilities receive power from central sector projects in proportion to their entitlement in

line with guide lines as per CERC regulations. This power is made available at

generator terminal of the respective projects and is wheeled through Power Grid

system till it is made available at their respective periphery. The bills in respect of

generator comprises two parts . One part is energy availed at generator terminal and

the other part of the bill is raised by Power Grid on account of wheeling of power

through their system up to the state periphery. The quantum of energy which reflects

in a monthly bills is based on the Regional Energy account prepared by NRPC

(Northern Regional Power Committee).

1 b. Free power Entitlement:

Every state has free power Entitlement in all those projects which have been

commissioned in their respective territory . This entitlement is due to home state

benefits on account of sacrificing its potential as well as water usage rights of the

people of that state. In addition to above free power entitlement of the state , the utilities also

avail equity power entitlements if any which is at the discretion of the respective governments

and is given to the state as first right to mitigate the shortages during deficit months.

c. Through Banking :

Transaction / procurement of Power through Banking is also one of the modes which is

considered as a cashless transaction and this energy exchange arrangement is on equal basis

i.e. the obligation of the state to return the banked energy is restricted to the extent to which

the energy has been banked with it during the deficit months. The average rate as agreed as per

agreements (Unscheduled Interchange rates based on prevailing grid frequency conditions at

that point of time) are kept to account for unadjusted quantum at the end of banking cycle.

This arrangement facilitates when there is large variation in demand pattern during deficit

months on account of fluctuating weather conditions and provides real time operation and

increase or decrease of quantum with the mutual consent of both the parties without any

financial implications on either party. With the above arrangement the surplus power available

during the monsoon months is returned for meeting the previous year banking obligations as

well as for Advance Banking (contra banking) arrangements.

d. Unscheduled Interchange (UI):

This does not fall under any category of mode of transaction of power, but under


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prevailing grid frequency conditions, power does flow perforce which also provides

additional assistance to mitigate the instantaneous shortage of power. This perforce

transaction of power is regulated as per CERC regulation on Unscheduled interchange

of power issued by Central Electricity Regulatory Commission from time to time.

However, the under drawl/over drawl of power should not exceed the specific limit or

otherwise, the same shall lead to the collapsing of grid. It is also added that any

violation through UI against the prescribed norms shall lead to penalty to the

concerned utility.

e. Transaction of power through energy exchange:

In this mode of transaction of power, the surplus power available on day-ahead basis is

disposed off through exchange on the available rates. Similarly through this mode,

procurement of power is also carried out to meet the immediate demand of shortages.

f. Sale/ purchase of power through Tendering process:

In this mode of transaction, bids are invited from different utilities for their

participation in the tendering process and the bidder who qualifies the desired terms

and conditions is given order for supply of power.

1.3 Constraints in Energy Management

In the real time operation generally power system is encountered with

situations which cannot be foreseen and tied up for sale/purchase arrangements due to

unexpected variations in demand and supply position. This is more predominant in the case

of states where on one hand load is dependent upon the weather conditions and on the other

hand on own generation, which is purely hydro based through run of the river schemes,

depends upon the inflows that can also not be very accurately predicted. Under such

conditions the utilities have to rely upon their thermal power shares which are costlier than

hydro power and affects the economy of the state.

Some surplus power perforce, under real time operation gets transacted

through Unscheduled Interchange mode (Under Drawl) and exporting utilities are paid for

this unscheduled energy in accordance with the prevailing frequency conditions in the grid

under UI mechanism.


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A part of energy assessed surplus on day a head basis (24 hrs) is sold through

Energy Exchange on the best available rates which are more or less influenced by the

frequency prevalent in the grid.

---------------X--------------------X-------------


MANAGEMENT

2.1 Introduction

SLDCs (State Load Dispatch Center) have brought a revolution in the field of Energy

management . In fact it has proved its worth in giving clear picture of day to day energy

transactions. Communication System is considered as backbone of the SLDC which

provides support to the SCADA system and plays a vital role to ensure interconnectivity of

various control centres. The various modes of communication have given birth to SLDC

centres and fulfilled many dreams which were impossible before the establishment of such

centres. They have given us the following gifts:

0 Created Grid Discipline.

1 Improved voltage profile and frequency.

2 Reduced frequent Grid failures.

3 Optimum utilization of available resources.

4 Visualization of real time availability of data/ events occurrence.

Efficient Power System Operation & Load Management.

Reduced gap in Demand - Supply position (Better regulation).

Better voltages at Consumer end.

Low per Unit cost.

In fact the above stated gifts have given wide opening to a very important aspect i.e energy

management in an efficient manners. The energy management is an ultimate goal for an

electrical utility which could be achieved effectively with the birth of SLDC. Thus SLDC


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has made possible all kinds of developments in the field of power system such as

development of trading market, power exchange , effectiveness in power transactions

through different modes.

Application of SLDC/NRLDC made possible , quick restoration of

the system during transaction of power, when there is a chance thatthe system may have

to face instability which ultimately leads to collapsing of the grid owing to over drawl by

some utilities under low frequency conditions attributing to grid indiscipline and violation

of regulations.

2.2 Load Despatch Centres in Northern India

As per the decision of Govt. of India it became mandatory to set Regional Load DespatchCenters and State Load Despatch centres alongwith Sub-Load Despatch Centres with

ultimate aim of National Grid.

In compliance to above orders of Govt. of India, under ULDC scheme (Unified load

Despatch Centre), all the states established SLDCs as well as SUB-LDCs in line with terms

and conditions of MOU(Memorandum of Understanding) signed between the all concerned

utilities which are as under:

5 Regional Despatch Centre at Delhi

6 SLDC at HPSEBL Shimla

7 SLDC at HVPNL Panipat

8 SLDC at UPPCL Lucknow

9 SLDC at DTL Delhi

10 SLDC at BBMB Chandigarh

11 SLDC at PSPCL Patiala

12 SLDC at RSEB Rajasthan

13 SLDC at JKPPD Gladni

With the increasing demand and utilization of electricity, an electrical

engineer should be well versed or at least acquainted with the various


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aspects of generation, transmission and distribution of electricity, and at

the same time must be capable of analysing energy management

aspects. The introduction of SLDC units in the states have made

it possible to ascertain the eventualities in an effective mannerand has given a wide opening for energy management as a tool.

In this scenario of integrated system it has become essential to

have SLDC unit in every state of the country which provides

economical despatch and regulation of power.This system uses an

application of optical fibre ground wire as a mode of communication ,

PLCC system, SCADA system. Above all, UPS also plays an important

role to provide uninterrupted power supply to the power system and

ensures reliable system. The installation technique of fibre optics is

critical one in the commissioning process. The special connectors and

techniques are used for joining fibres. The tool used for splicing purpose

is special one. That instrument is known as splicer

In the Northern Region , SLDCs have been established in the following hierarchi andeach SLDC unit collects data from remote with the help of RTUs (Remote Terminal

Unit) . To facilitate effictive collection of data , each SLDC is further classified into Sub -

LDCs.

The hierarchical structure of above stated units is as shown in the fig below :


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Fig. 1 Hierarchical structure of Load Dispatch Centres in Northern India

2.3 Real Time Dynamic Security Assessment

The Electrical Grid changes constantly with generation plants frequently coming online or

off-line as required to meet electrical demand. In state of the art electric utility control

centres, grid operators use energy management systems (EMS) to perform network and

load monitoring. Limits to flows and voltages are assigned on the basis of transmission line

thermal limits and off load studies of voltage and transient dynamic stability. Theassumptions that the grid power flows settle down to steady state condition is reexamined


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in real time as the transmission grid conditions change in real time. In real time operation it

becomes essential to watch grid discipline under dynamic conditions. A software

designated as Dynamic Security Assessment is used to simulate the impact of the potential

of electric fault conditions and grid disturbances.

The SLDCs (Load Dispatch Centres) have made it possible to run

such models attributing to dynamic grid security and hence, contributed maximum towards

grid discipline under real time operations. All these functions perform effectively after the

establishment of SLDCs. These load despatch centres have given birth to power exchange

and development of power trading market .

With grid frequency point of view , any action taken by SLDC shall

depend on the grid frequency. This action is initiated by SLDC only when there is a

change in the system status i.e tripping of generating station . A load crash within the state

or a frequency change due to imbalance in load- generation.

CHAPTER 3 AVAILABILITY BASED TARIFF (ABT)

3.1 Introduction


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The term Availability Tariff stand for a tariff structure for power spply from generating

stations on contracted basis . The power plants have fixed and variable cost . The fixed cost

elements are interest on loans , return on equity , depreciation , O&M expenses ,

insurance , taxes and interest on working capital. The variable cost comprises of the fuel

cost i.e coal and oil in case of thermal plants and nuclear fuel in case of nuclear plants . In

the availability based tariff mechanism , the fixed and variable cost components are treated

separately . The payment of fixed cost to generating stations is linked to a availability of

the plant , i.e its capability to deliver MWs on a day - by- day basis. The total amount

payable to the generating company over a year towards the fixed cost would depend on the

average availability of the plant over the year.In case the average actually achieved over the

year is higher than the specified norm for the plant availability , the generating company

would get a higher payment . In case the average actually achieved over the year is lower

than the specified norm for the plant availability , the generating company would get a less

payment . Hence, name Availability Tariff. This is first component of Availability Tariff

and is termed as capacity charges.

The second component of ABT is the energy charge and this would

comprise of variable cost of power plant for generating energy as per the given schedule.

The third component attributes towards payment for deviations from

schedule at a rate dependent on system conditions.

Initially, ABT was made applicable only to the central generating stations

which were having more than one beneficiary. But with its application, Central Electricity

Regulatory Commission (CERC), found its suitability towards quality improvement of

power and thought of its expansion to cover even Intrastate systems as well as. ABT has

shown improvement towards following disruptive trends in power sector:

a. Rapid and high frequency deviations causing damage and disruption to large scale

indusrial consumers.

b. Frequent grid disturbances resulting in generators tripping, power outages and

power grid disintegration.

3.2 Details about ABT

Availability for the purpose of ABT means the readiness of the generating stations to


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deliver ex-bus output expressed as % of its related output capability as per rated capacity.

Availability of thermal generating station for any period shall be the percentage ratio of

average Sent Out Capability for all the time blocks during that period and rated Sent Out

Capability of the generating station.

Availability based tariff includes :

a. CAPACITY CHARGES

a function of the Ex- bus MW availability of power plant for the day

b. ENERGY CHARGES

MWh for the day as per ex- bus drawal schedule for the utility.

c. ADJUSTMENT FOR DEVIATIONS (UI Charges)

(Actual energy interchange in a 15 min time block- scheduled energy Interchange

for the same time block) x UI rate for that time block.

Total payment for the day = a + b (+/-) c

3.3 Scheduling

3.3.1 Introduction

The following procedure is adopted for scheduling:

0 Each day of 24 hrs starting from 00.00hrs is divided into 96 time

blocks of 15 minutes each.

1 The generating stations make advance declaration of their capacities for

generation in terms of MWh delivery of power for each time block of the next

day.

0 While declaring capability , the generator should ensure that the

capability during peak hours should not be less than that during other

hours.

1 Based upon such declaration , the Regional Load Dispatch Centre


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(RLDC) shall communicate to the various beneficiaries their respective

shares of the available capability.

2 After the beneficiaries give their requisition for power based on the

generation schedules , the RLDC shall prepare the generation schedules

and drawl schedules for each time block after taking into account

technical limitations and transmission constraints.

3 The schedule of actual generation is quantified on ex- bus basis ,

whereas for beneficiaries , scheduled drawls shall be quantified at their

receiving points.

4 For calculating the drawal schedule for beneficiaries , the

transmission losses shall be apportioned in proportion to their drawls. In

case of any forced outage of the unit, or in case of any transmission

bottleneck , RLDC will revise the schedules. The revised schedules shall

become effective from the 4th time block, counting the time block in

which the revision is advised by the generator, to be te 1 st one.

3. 3.2 Day Ahead Scheduling

10 A.M - Central Generating stations advise foreseen plant-wise ex-

bus MW, MWh availability for next day.

11 AM - RLDC advises SEBs their MW , MWh shares in the foreseen availability

of central plants.

3 PM - SLDCs furnish their time-wise MW requisition from the above, and

schedule of bilateral exchanges, if any.

5PM - RLDC complies these and issues generation schedules for central plants

and drawl schedules for SEBs, for the next day starting at midnight.

10 PM - Revision of the above, if required , by any new development during the

day.

11 PM - Schedules frozen for the next day.

3.4 Features of ABT


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The availability based tariff has the following features.

0 It brings about enhanced grid discipline.

0 Economically viable power with right pricing.

1 Encourages usage of Merit Order Dispatch / Economic Dispatch in India.

2 It helps in addressing grid disturbance issues

1 It helps observing any kind of gaming and avoiding the same.

2 It requires special meters , remote metering and communication

mechanisms to facilitate reading of the meters in time.

3 Facilitates addressing regularity assets.

4 It acts as an interface with various stakeholders to enable

implementation and benefits to all.


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CHAPTER 4 ROLE OF FREQUENCY IN ENERGY

MANAGEMENT

4.1 Frequency is good or high and the state is Overdrawing.

- No Problem and No. Action Required-

However for enhanced Optimization may resort to following :

i. Reduce own generation to the extent possible and increase overdrawal so long as

frequency is above 49.8 Hz.

ii. Restore consumer load that had been shed, provided Tariff/ Realization rate is higherthan current UI rate.

iii. Increase, CGS requisition , if some part of the entitlements had not been requisitioned

earlier.

4.2 Frequency is good or High and the state is Underdrawing.

Action required is as under:

i. Reduce own generation to the extent possible , if the frequency is above about 49.8 Hz.

ii. Restore consumer load that had been shed, and reduce under-drawn

iii. Reduce CGS requisition, provided the previous two actions have been taken and the

frequency continues to be above 50.2 Hz, bialateral sale to the needy neighbour can be

tried.

4. 3 Frequency is Low , and the state is Overdrawing.

Action required is as under:

i Increase own generation to the maximum possible extent.

ii. Curtail consumer load . Load shedding to be graded balancing between UI price and

consumer category .

iii. Increase CGS requisition to full entitlement( If not requisitioned fully earlier ) and


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arrange for bilateral purchase from another SEB/CGS.

4.4 Frequency is Low and the state is Underdrawing.

i. Increase own generation to the extent possible, provided the frequency is belowabout 49.5 Hz (comparing variable cost with current UI price).

ii. Curtail consumer load, by shedding low priority load (provided UI earning for the

SEB justifies such load shedding). This is totally optional, and helps the grid.

iii. Increase C GS requisition to full entitlement ( if not requisitioned fully earlier) and

earn UI or sell the surplus through a bilateral agreement)

The above scenarios shows that action to be taken for managing energy turbulences

depends upon the prevailing frequency and is independent of whether over-drawing or

underdrawing .

CHAPTER 5 DEVIATIONS FROM SCHEDULE


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5.1 Unscheduled Interchange (UI)

The energy actually supplied by the generator may differ from what was scheduled . If the

actual energy supplied were higher than scheduled , the generating station would be

entitled to receive a payment for excess energy (deviation from schedule, termed as

Unscheduled Interchange(UI) ) at a rate dependent on frequency at that time. I f the energy

actually supplied is less than what is scheduled , the generating station shall have to pay

back for the energy shortfall, at the same frequency .

The relationship between the above UI rate and grid frequency for

interstate system is specified by CERC. The relationship between n UI and Frequency is as

shown in the fig. below.

Fig. 2. Relationship between UI rate and Grid Frequency

48.8 49 49.2 49.4 49.6 49.8 50

50.2 50.4 50.6

Frequency (Hz)

600

400

200

0UIRate(P

aisa

/kWh)


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It is seen from the above figure that when the frequency is 50.5 Hz or higher , the UI rate is

zero , which means that the generating station would not get any payment for the extra

energy supplied . It would burn fuel for producing this extra energy , but would not get any

payment for it.If the actual energy supplied were less than scheduled energy , the

generating station would still be paid for the scheduled energy (at its energy charge rate )

without having to pay back anything for the energy shortfall. I t would thus be able to save

on fuel cost ( for the energy not generated) and retain the energy charge as net saving .

There is thus a strong commercial incentive to back down generating during high

frequency situations .

On the other hand , when frequency goes down, the UI rate ( for both

over supply and under supply ) goes up like anything and touches the level of Rs. 5.7 per

unit at frequency of 49.0 Hz. At a frequency of 49.5 Hz , the UI rate is Rs. 3.45 per unit.

For any short fall , the generating station shall have to pay back at the same rate . It would

thus have a strong commercial incentive to maximize its generation during periods of such

low frequency.

A similar scheme operates for the States ( beneficiaries) as well. Any

state drawing power in excess of its schedule has to pay for the excess energy at the same

frequency - dependent rate. The high UI rate during low frequency conditions would

induce all states to reduce their drawal from the grid, by maxamizing their own generation

and / or by curtailing their consumer load. If a state draws less power than scheduled , it

payus for scheduled energy quantum at the normal rate and gets paid back for energy not

drawn at a much higher UI rate . On the other hand , during high- frequency conditions , a

state draw extra power at a low rate and is thus encouraged to back down its own costlier

generating stations . An under-drawal during high- frequency conditions means that the

state pays for the scheduled power quantum unnecessarily. It should either reduce its

schedule or increase its drawal.

5.2 UI rate determination

For the purpose of determination of UI rate , the energy is metered in 15 - minute time

blocks, since frequency keeps on changing and subsequent UI rate . The metered energy is

compared with the scheduled energy for that 15- minute time block and the difference (+

or -) becomes the UI energy . The corresponding UI rate is determined by taking the


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average frequency for the same 15- minute time block into account.

For each Central generating station and state , the actual energy has

to be metered on a net basis , i.e algebraic sum of energy metered on all its peripheral

interconnection points for every 15- minute time block. All UI payments are made into and

from a regional UI pool account, operated by the concerned RLDC.

5.3 Unscheduled Interchange (UI) Vs Marginal Cost.

UI rate is tightly linked to grid frequency. As the frequency is same all over an A.C.

system and can be readily seen through a simple frequency meter , it is easily possible to

know the prevailing UI rates anywhere in the system . With this on line knowledge of the

current UI rate , a state would know what it would have to pay for an extra MW that it

may draw from the regional . It can readily compare this with the fuel cost it would save if

generation were reduced by one MW at its own station, having the highest variable cost. If

the UI ratre is lower than the latter, it would be beneficial; for the state to reduce its own

generation and draw the replacement energy from the regional grid, till it has backed down

all generation having a variable cost higher than the current UI rate . In the process state's

marginal generation cost would move down, towards the prevailing UI rate.

Meanwhile, other states too would take a similar action in the same time

frame and total generation in the system would come down, resulting in a downward

movement of frequency and an upward movement of UI rate , till the attainment of a state

of equilibrium wherein the marginal generation cost of every state would become equal to

the UI rate.

On the other hand , if a state finds the UI rate to be higher than the variable

cost of any of its partly loaded generating units at any time , it would be financiallybeneficial for the state to maximize the output of all such generating units and thereby

reduce its drawal from the regional grid. The state would have an under- drawal, for which

it would get paid a UI rate higher than its marginal generation cost.

With similar action being taken by other states as well, the frequency would

tend to rise and UI rate would decline correspondingly, till equilibrium is reached wherein

the marginal generation cost of every state would equal the UI rate.

CHAPTER 6 A TRADING OPPORTUNITY UNDER THE


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SHADOW OF ENERGY MANAGEMENT

Let us refer fig. Given below. The two areas marked 'X' represent the off peak hour

capability of the central generating station , which State-C has not requisitioned, although

within its entitlement . The trading opportunities can be encashed both by the Generator as

well as Beneficiary , which are as under:

6.1 Trading Opportunity to be Availed by the GENERATOR

The capability (160MW) is now available with the Central Station and it has three options

before it ,which are as follows:

I. Back down the station during off peak hpurs,. I.e. Generate power onlyaccording to the schedule given by RLDC by aggregating the rerusition of the

three states.In this case , the station gets capacity charge for the day corresponding

to its availability declaration (900 MW) and energy charge to fully recover its fuel

cost for generating the scheduled quantum of energy during the day.

II. Find a buyer ( other than State -C) for the above off - peak surplus and generate

power adding the MW agreed to be taken by this buyer to the aggregate schedule

for states - A,B and C. A s the station is already being paid capacity charges for

900 MW, it may not be too particular about further fixed cost recovery. As long as

the energy agreed upon is higher than the fuel cost per KWh of the station , it

would be beneficial for the station to enter into such a deal. I t would also reduce

the technical problems associated with backing down of the station and improve

the station's efficiency.

III. Instead of selling the off- peak surplus power through a bilateral agreement as

described above , the station may accept the schedule given by RLDC, but

generate power to its full capability of 900 MW even during off peak hours .The

result would be an over supply of 160 MW ( as a deviation from schedule) , for

which the station would get paid from the regional UI pool account at the

prevailing UI rate. In fact , it would be a stale to the regional pool and would

make a financial sense as long as the prevailing UI rate is higher than the fuel cost

per KWh of the station.

6.2 Trading Opportunity to be Availed by the BENEFICIARY


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The above options for the generating stations arise only in case a state has not requisitioned

its full entitlement . In fact, the same three options are available to State -C , before they

get passed on to the Central station and are as follows:

i. Requisition power from the Central station only as per its own requirement and

draw power as per the resulting schedule.

ii. Requisition full entitlement from the Central station for the entire 24- hour period,

find a buyer for the off peak surplus and schedule a bilateral sale. This would

make sense as long as the sale rate per kWh is more than the energy charge rate of

the Central station.

iii. Requisition the full entitlement for the entire 24 - hour period , but draw power

only according to its actual requirement. In fact , this would be a pre-planned

deviation from schedule for which State - C would get UI payment. A ll that State

- C has to watch for and be vigilant about is that UI rate during the off- peak hours

remains above the energy charge rate of the Central Station . In case the

frequency rises and UI rate falls below the energy charge rate of the concerned

Central station , State -C shuld reduce its requistion and thereby stop under -

drawing.

The above methodology for trading shows that under the Energy Management regime

there are equal opportunities both for Generator as well as Beneficiaries.

CHAPTER 7 OPEN ACCESS , WHEELING AS AN


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IMPORTANT TOOL OF ENERGY MANAGEMENT .

7.1 Open Accessand Wheeling

Open Access and Wheeling are supposed to be one of the important tools as far as

Interstate trading is concerned.Without these components , it is not possible to go in for

trading between the two utilities . The following reasons attribute to the necessity of such

tools formanaging energy in Interstate trading:

1. When utility 'A' trades power to utility 'B' and both are at different places, then

Utility A has to take open access from the utility whose system shall be used by A

to make the power available at the periphery of B and for such open access , A has

to pay Wheeling charges to the owner whose system A is using.

2. Without this arrangement , the transactions of power so made shall lead to

litigations as there is a chance for many disputes to arise.

OPEN ACCESS and WHEELING generally involve two parties , One supplying a certain

quantum of power to the other through the regional / state grid. Any such transactions

involves a number of parties and disputes could arise in scheduling , energy accounting and

commercial settlement , unless an appropriate framework is in place.

Let us take a case where party A has contracted to supply 10 MW round the

clock to party B at a certain price. Party A has to transact that power through regional Grid

system to make that power available at the periphery ofparty B . Since , the losses in the

system are expected to the tune of .5 MW , A has to bear these losses also as per contract to

supply power at the periphery of B. In such a deal A shall bear expenditure of loss as well as

pay wheeling charges to the regional grid system so as to settle the transaction without

litigation.

A contracted sale or purchase involves the following:

Identification of counterpart

Agreeing on power quantum, duration, price and other terms

Ascertaining the adequacy of transmission system

Payment of applicable transmission / wheeling charges and absorption of


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wheeling losses

Day ahead scheduling through SLDC/RLDC concerned.

Payment security for transaction.

An agreement is also executed between both the parties which ensures commitment by both

the parties to ensure transaction of power as per terms and conditions of the agreement

without litigation.

7.2 Issues Involved in the Transactions

There may be certain constraints in supplying powers which are as under:

There may be a chance that a seller fails to schedule the supply of the agreed

quantum of power due to short fall in its own power availability or the buyer fails to

schedule the drawal of the agreed quantum of power due to fall in its requirement , it

will mean a contractual default . The agreement between the parties must specify as

to how much defaults can be handled .

Another issue would be as to how a party selected its counterpart and agreed on the

price and whether these have been done judiciously.

Required checks and balances may even delay the finalization of agreement and

trading opportunities may be missed.

Regarding settlement of above issues one may adopt the route of

UI , but it may lead to other complications as there is no certainty of the price and further

RLDC may ask to curtail the supply due to transmission constraint. However, it has the major

advantage such as there is no commitment about the quantum. A lso no question can be raisedon price from audit angle. Thus UI rate provides an alternative to "Open Access" and

"Wheeling" and can be taken when one prefers flexibility over certainty .


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CHAPTER 8 POWER EXCHANGE IMPLEMENTATION

IN INDIA

8.1 Introduction

In line with the mandate provided by the Indian Electricity Act 2003 and the National

Electricity Policy , the Central Electricity Regulatory Commission (CERC) has issued a

number of Regulations to facilitate trading and introduction of competition in the

Electricity Sector in the country . Open Access in inter-state transmission was introduced

in May 2004 which facilitated the development of the bilateral market in the country.

The responsibility for the development of the Electricity Market in the country has beenentrusted to the Appropriate commission as per electricity act 2003 . The Indian electricity

grid code was introduced in Feb 2000 with subsequent revision in April,2006 and the

settlement system was introduced in 2002-2003 . The ABT mechanism provided the

framework for scheduling and handling of imbalances . These two building blocks together

provided the basic rules for system operation and the commercial settlement . Open Access

in interstate transmission was introduced in May 2004 and gave birth to bilateral market in

the country. On the basis of such developments , CERC issued guidelines for

establishment of Power Exchange in Feb 2007 and in principal approval ws granted to the

first Power Exchange in August 2007.

8.2 Regulatory Framework for power exchange Implementation

The Open Access in the Interstate Transmission Regulations 2004 provided only for the

bilateral Transactions and the system of application of transmission charges was in Rs. /

MW/Day. These methodologies for transmission charges & Losses were not conductive to

the operation of a common platform for electricity trading i.e power Exchange operations.

So necessary amendments in the regulation was required for implementation of Power

Exchange . Accordingly, the regulation s for Open Access in Interstate Transmission were

revised by CERC to include Collective Transactions Discovered on a Power Exchange and

anew regulation became effective fro 1st April 2008. So , the CERC Open Access

Regulations , 2008 made the following provisions :

a . Transactions were categorized as Bilateral and Collective ( through PowerExchange)


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b. Nodal Agency for two types of transactions was identified. National Load

Despatch Centre (NLDC) was designated as nodal agency for Collective

Transactions . The Regional Load Despatch Centres (RLDC) were the

designated agencies for bilateral transactions.

c. Transmission losses were applied at both the points of injection and drawal .

The sellers are required to inject more and the buyers draw less than the

traded quantum to compensate for losses.

d. Regulations placed great emphasis on the empowerment of the SLDCs. NOC/

Standing clearance was required to be obtatined by State Utilities / Intra - State

Entities from the SLDC. The SLDCs are obliged to respond within 3 days to

any request for an NOC as per the regulations. The SLDC may charge an

appropriate fee for such NOC/ Standing Clearance .

e. T he methodology of application of transmission charges moved from 'Contract

Path' to a methodology closer to the 'Point of Connection' Charges ' for

collective transaction.

f. Operating charges for collective transactions @ Rs. 5000 per day per entity

involved are applied. All buyers within a state are clubbed together into one

group and all sellers within a state are clubbed together into another group by

the power exchange . Each group of buyers and sellers is counted as a separate

entity for scheduling and leavy of operating Charges.

8.3 Power Exchange Implementation in India

The power exchange in India has many features such as Voluntary participation, Day ahead

transactions , Physical delivery of Energy , Double sided bidding , Hourly bids ,

Uniform pricing , Multiple Exchanges envisaged and Congestion Management .

8.4 Functional Power Exchange

Indian Energy Exchange ( IEX ) , the country's first power exchange , made an application

for grant of permission to setup a Power Exchange in March 2007 and an in- principle

approval was accorded by the CERC on 31st August 2007 . IEX commenced operation

from the 27th June 2008 after the Rules and Bye Laws were approved by CERC and


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permission was granted to commence operations . The second Power Exchange of India

(PXIL) was granted in- principle approval on 27th May 2008 . PXIL went through a

process of Regulatory approval similar to that of it's predecessor and it commenced

operations on 22nd October 2008.

8.5 Competition among Exchanges

The Regulators have provided for multiple Power Exchanges to exist simultaneously in one

physical market . Light handed regulation has been adopted and the Power Exchanges have

been given full functional autonomy. This allows for competition amongst the existing

Power Exchanges and an automatic system of checks and balances .The charges collected

by the power exchanges for the services rendered are automatically regulated by the market

forces.

8.6 Information Exchange between NLDC and Power Exchanges

The exchange of information is fully automated between NLDC and Power Exchanges ,

NLDC and the Regional Load Dispatch centers (RLDCs) . The bidding window for

submission of bids in the Power Exchange is from 1000 Hrs. to 1200 Hrs. Information is

exchanged between NLDC , Power Exchange and the RLDC as per a protocol defined in

the procedure for Scheduling of collective Transactions . A provisional solution is given by

the Power Exchanges to the NLDC at 1300 Hrs for congestion if any. In case of

congestion , NLDC advises the Power Exchanges about the limits of scheduling . The

Power Exchange submits the application for scheduling of collective Transactions by

1500Hrs and the approval for scheduling is communicated by NLDC by 1730 Hrs.

8.7 Regulations governing the process of Energy Management

The following regulations/codes govern the process of procurement o/ disposal of power:

0 Central Electricity Regulatory Commission (Unscheduled Interchange

charges and related matters) Regulations, 2012.

1 Central Electricity Regulatory Commission (Indian Electricity Grid Code

Regulations, 2012.

2 Central Electricity Regulatory Commission (Sharing of inter-StateTransmission Charges and Losses) (Second Amendment) Regulations, 2012.


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3 CERC(Terms and Conditions for Tariff determination from Renewable

Energy Sources) Regulations, 2012.

4 Indian Electricity Grid Code Regulations, 2010

5 Terms and Conditions of Tariff, Regulations for 2009-14


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SECTION -II

ENERGY MANAGEMENT

HPSEBL

AS

A SPECIAL CASE


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CHAPTER 1 STATUS OF SLDC IN HPSEBL

1.1 Setting up SLDC/SUB-LDCs in Himachal Pradesh

In compliance to the decision of Govt. of India, HPSEBL under ULDC Scheme, incoordination with PGCIL established a State Load Despatch & Communication Centre

(SLDC) at Shimla and 1No. Sub-LDC at Kunihar and 1No. Sub-LDC at Hamirpur with

RTUs at different locations.


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Fig 3. Location of SLDC and Sub-LDCs in Himachal Pradesh

The hierarchical structure of SLDCs and Sub-LDC is also given in the fig. below which

presents the load centers in Himachal Pradesh alongwith the location of their respective

RTUs (Remote Terminal Units) situated at different locations . These RTUs are mostly

connected to their Sub-LDCs through Power Line Carrier Communication System and

further to SLDC through wideband system.


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Fig.4 Hierarchical Structure of SLDC & Sub- LDCs

1.2 Sub-LDC at Kunihar

It comprises 8 No. RTUs(Remote Terminal Units) installed at different locations inthe upper reaches of Himachal Pradesh :

0 Kunihar

1 Bhaba

2 Jeori

3 Giri

4 Andhra

5 Solan

6 Jutogh

7 Baddi

The connectivity of the above stated RTUs is as shown in the fig. below. The RTUs are

connected to SUB-LDC Kunihar through PLCC link. Each RTU is provided with a modem

which converts digital signal into analog signal. The analog signal, thus transmits through

PLCC system upto SUB-LDC. After reaching SUB-LDC, again the signal is converted into

digital signal with the help of modem which are placed in the equipment called

CFE(communication front end). The signal after its conversion to digital form, enters theMUX placed in the control room of SUB-LDC where it gets multiplexed and enters

OLTE(optical line terminal equipment) where the digital/electrical signal is converted into

optical signal and transmits through OPGW(optical ground wire) and reaches SLDC Jutogh

where the signal again enters OLTE at Jutogh at the rate of 155 mbps as an optical signal

and further enters MUX as digital/electrical signal at the rate of 2 mbps and gets

demultiplexed when it comes out from the MUX .Here the signal gets divided into two

parts. First part is a signal of 64kbps which enters the exchange through MDF(main

distribution frame) and facilitates speech, whereas the second part of the signal is of 19.2

kbps which enters the HUB of control room at Jutogh as data signal and is processed with

the help of SCADA system.


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Fig.5 SUB-LDC KUNIHAR (Connectivity of RTUs)


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1.3 Sub-LDC at Hamirpur

It comprises 10 No. RTUs(Remote Terminal Units) installed at different locationsin the upper reaches of Himachal Pradesh :

8 Hamirpur-I

9 Hamirpur-II

10 Dera

11 Kangra

12 Malana

13 Jassore

14 Bassi

15 Mandi

16 Kangoo

17 Largi

The connectivity of the above stated RTUs is as shown in the fig. below. All RTUs are

connected to SUB-LDC Hamirpur through PLCC link except Kangoo which is connected

through wideband link. Each RTU is provided with a modem which converts digital signal

into analog signal. The analog signal, thus transmits through PLCC system upto SUB-

LDC. After reaching SUB-LDC, again the signal is converted into digital signal with the

help of modem which are placed in the equipment called CFE(communication front end).

The signal after its conversion to digital form, enters the MUX placed in the control room

of SUB-LDC where it gets multiplexed and enters OLTE(optical line terminal equipment)

where the digital/electrical signal is converted into optical signal and transmits through

OPGW(optical ground wire) and reaches SLDC Jutogh where the signal again enters

OLTE at Jutogh at the rate of 155 mbps as an optical signal and further enters MUX as

digital/electrical signal at the rate of 2 mbps and gets demultiplexed when it comes out

from the MUX .Here the signal gets divided into two parts. First part is a signal of 64kbps

which enters the exchange through MDF(main distribution frame) and facilitates speech,

whereas the second part of the signal is of 19.2 kbps which enters the HUB of control room

at Jutogh as data signal and is processed with the help of SCADA system.


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Fig.6SUB-LDC HAMIRPUR (Connectivity of RTUs)


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1.4 Interconnectivity of SLDC & SUB-LDCs of H.P.

Fig.7 INTER CONNECTIVITY DIAGRAM OF SLDC -

SUB-LDCs OF H.P.

The above diagram shows interconnectivity of SLDC Shimla with SUB-LDC Hamirpur

and Kunihar. The data from Hamirpur reaches Kunihar on wideband system through

OPGW where it combines with data of SUB-LDC Kunihar and a combined data packet

reaches Jutogh through wideband system through OPGW and is processed in the control

room at Jutogh separately. Then afterwards,again a combined data packet comprising data

of SLDC Jutogh, SUB-LDC Hamirpur and SUB-LDC Kunihar takes its way to NRLDC on

OPGW through wideband system.

The combined connectivity diagram showing combined connectivity of both the

SUB-LDCs alongwith SLDC and RTUs of respective SUB-LDCs is as shown in the figbelow.


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The figure shows the connectivity between RTUs and SUB-LDCs on

PLCC system and between SUB-LDCs and SLDC on wideband through OPGW. The

connectivity of Kangoo substation is on wideband system. The communication through

wideband system has been experienced to be more reliable than through other mode of

system. In the existing SUB-LDCs, there is enough provision for future expansion. Thesystem will prove its worth when atomization shall come into existence.

Fig.8 COMBINED CONNECTIVITY DIAGRAM

CHAPTER2 BACKBONE TO COMMUNICATION


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SYSTEMAT SLDC SHIMLA

2.1 Introduction

In the absence of certain tools, communication system standsnowhere. These tools act as backbone to the system and assists the system in all respects.

These are as under:

0 OPGW (Optical Ground Wire) and its Installation

1 PLCC System

2 PABX System

3 RTU

4 UPS

The details are as under:

2.2 OPGW and its Installation

OPGW provides overhead telecommunication system.

Fig.9 OPGW (Optical Ground Wire)

The central part of this cable is composed by a dielectric optical core comprising six fibres

stranded around a central support. An aluminium tube is extruded around this optical core

and the cable is finished with one or two layers of an aluminium clad steel. Tight Buffered

Optical Fibre (multi mode)

50 m Core

125 m

Optical Cladding

250 m

Primary Coating

50 m Core

Guided Light Propagation

Glas

Plastic


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cable is used for cable routing within buildings. Typically containing around 16 fibres (12

cores, 4 cores and 8 cores are also common) this type of cable offers ease of installation

and fibre protection suitable for internal use. each of the fibres within the cable is

individually protected by a plastic coating with kevlar strengthening and sheathing giving

overall protection. Low Smoke Zero Halogen Sheaths are common in this type of cable. To

withstand harsher external conditions Loose Tube cables are used for outside installations

in duct work or trenches. As the name suggests groups of fibres are suspended in a gel

filled tube within a heavily protected cable. As the fibre has no physical contact with the

tube it is less prone to damage during the stresses associated with installation and

temperature contraction and expansion. The gel used within the tubes protects against the

ingress water. Many different fibre counts are available as few as four or as many as 96

cores are common. Thus origination of OPTICAL fibre has made communication system

reliable and effective and acted as an efficient tool in the energy management syste

2.3 Testing of Optical Fiber Links

To test a link, the correct mating connectors must be fitted to the test leads.There are many

types of fibre connectors as each fibre type (multimode, single mode and POF) has its own

family of connectors. The most common types are ST, SC and SMA.

Before testing the link, you must know how much loss to expect at the wavelength of

interest. If you want accurate results, the testing should be performed at the wavelength at

which the fibre is to be used. Link loss can be readily calculated from the manufacturers

data (loss per unit length in dBs), the actual link length, and the number of connectors and

joints (if any) in the link. Without this data, you cannot determine whether or not the links

performance is satisfactory. Do not assume there are no problems because a link works

when connected to the terminaL equipment. Some faults degrade link performance withtime (e.g. bad terminations).


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Fig. 10 TYPES OF FIBRE CONNECTORS

2.4 Monitoring of Status of OPGW

The status of OPGW whether healthy or faulty is monitored by using the equipment

named as FLXER PLUS. This equipment confirms that the broadband is as per actual and

functioning properly. If there is fault in the OPGW network, the alarm appears on the map

of the network. The faulty part of the OPGW appears red on the screen of FLXER PLUS.

The following diagram represents the connectivity of FLXER PLUS and FLXER with

OPGEW map.

Fig.11 Test Diagram for Monitoring of Status of OPGW

The map on the screen of FLXER PLUS shows the network connectivity of different

stations connected through OPGW appears as under:

Fiber Optic Connectors

F

C

P

C

FCPC

SCPC

STPCSCPC

FLXER

PLUS

FLX

150/6

FLX

150/6

Hamirpur Gaggal Kunihar Jutogh


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Fig. 12 Map of Network Elements of Different Locations

The details of status of different network elements are ascertained by using specific

commands on FLXER PLUS. If the status is healthy, the connectivity appears green and if

the status is unhealthy, the connectivity appears red.

2.5 PLCC System

PLCC system plays a vital role in the establishment of communication system. It

connects all the RTUs with SUB-LDCs. This is considered as one of the most economical

and reliable method of communication. In PLCC system, a bandwidth of 0-4 kHz is

confined to different applications as under:

The voice channel lies between 300 Hz to 2400 Hz.

The pilot frequency which is used for sending the dialling pulses and for the automatic

gain control of PLCC system lies within 3.57 kHz to 3.63 kHz.

The portion of band between 2.4 kHz to 3.57 kHz is used for data transmission on real

time basis.

It consists of two PLCC Terminals at two stations A and B connected together with the

help of HT transmission line and coupling equipment like wave traps (Line traps), coupling

capacitors, coupling devices and H.F. cable. For making data available of Solan substation

at Kunihar SUB-LDC, 2 No. Panels of BPL make, each at respective stations are placed

and are used for speech/data transmission of Solan Substation. At Solan end, the PLCC

panel is connected to RTU which collects various measurands of Solan substation and

transmit it through PLCC system upto Kunihar SUB-LDC and at Kunihar end the PLCC

panel is connected to CFE (Communication Front End) where the data from RTU is made

available for further processing.

The figures below shows the connectivity between RTU and SUB-LDC Kunihar in

between two stations and in between three stations. Incase of three stations, ie Giri, Solan

and Kunihar, the station Solan is called intermittent station and the connections of PLCC

Panels are made back to back, ie TX of one panel is connected to RX of other panel and

vice versa. For providing TX signal of -14 dB , oscillator is used and for measuring RX

signal of -20 dB, the level meter is used.


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A typical arrangement is shown in fig below:

SOLAN KUNIHAR

TX TX

RX RX

RTU PLCC Panel PLCC Panel CFE

TX= -16 dB

RX= -20 dB

GIRI SOLAN KUNIHAR

RTU PLCC Panel PLCC Panel CFE

PLCC Panels

TX {Trans Signal} = -14 dB

RX {Receive Signal} = -20 dB

Fig. 13 Connectivity Between RTU and SUB-LDC Kunihar &Solan

2.6 PABX System

This system is one of the important tools in SLDC system which provides fast, reliable and

efficient telephone system which is an essential requirement for the power system grid

operation. All control centres are equipped with PABX (Private Automatic BranchExchange Network). Each PABX has a number of local and remote subscribers. In SLDC


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Jutogh,

PABX system comprises 4 wire and two wire system. In the 4 wire

system, four wires are used for speech and two wires are used for signal, thus the four wire

system consists of total six wires. In the two wire system, the two wires are used for speech

and two wires are used for signal purpose. Thus, the two wire system comprises total four

wires. The PABX exchange is connected to the system through Main Distribution

Frame(MDF). It provides interconnection between exchange side and line side termination.

The implementation of integrated wideband telecommunication system network with PLC

and PABX procured under different contracts needs to be coordinated and requires careful

planning. The connectivity of PABX system with broadband system has made it possible

the communication between interstate SLDC units established at different corners in NR

Region. The requirement of PABX network in power system is unique.

With the development of wideband system it has become possible to

provide speech facility with the outside control centres also. This mode of communication

proves to be very economical as it involves initial cost of installation with very less

maintenance cost. The existing PABX exchanges are provided with a console which helps

in planning and programming at site and very easily one can provide new connections to

the utilities. These modern PABX systems are embedded with facilities such as provision

for future extension. In SLDC Shimla and in its respective SUB-LDCs, the PUNCOM

make exchanges have been provided. For maintenance purpose, AMCs (Annual

Maintenance Contract) have been given to the respective companies. The PABX exchange

in the existing system of SLDC Shimla provides speech communication to the remote

stations through PLCC system, to outside states through wideband system and within the

vicinity of SLDC campus through local subscribers.


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Fig.14 PABX Room In SLDC Shimla

The most important part of the exchange is its MDF (main distribution frame). It is divided

into two parts. The upper half is called exchange side and the lower half is called line side.

The local extension and console connections are terminated on termination block E1.Trunk lines are terminated on block E2. Both of these termination blocks are called

exchange side termination blocks. Similarly, on line side extension to all local subscribers

are given through L1 and connections to trunks are terminated at L2. E1 & L1 and E2 & L2

are connected through jumpers.The connectivity of PABX exchange at SLDC Jutogh with

MDF and console which is designated as SUPCON is as shown in the fig below:

-48 VOLT DC

POWER INPUT


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Subscribers

MDF

Trunks

POWER

UNIT

CONTR

OL

SERVICE

UNIT

TERMINAT

ION


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Fig.15 The connectivity of PABX exchange at SLDC Jutogh with MDF

and console

The PABX exchange has four functional groups which are as under:

Power Unit

Control Unit

Termination Unit

Service Unit

A brief description of functional groups of PABX is as given below:

Power Unit: It consists of a power filter card which filters out -48 Volt DC supply.

The filtered power is fed to Power supply unit card which generates

+/- 5 V, 12V DC, -9V DC. PSU card also generates 75 volt (RMS)

ringer voltage which is extended to telephone. The filtered -48V is

also fed directly to termination unit.

Control Unit: It handles all call processing functions. It takes all decisions and

controls all the functions done within PABX. It comprises PFC card, P

01 card. The function of P 01 card is to provide serial RS-232

interfaces for operator console/dispatcher console and communication

with PFC card. The PFC card scans the signalling status of each card

of termination unit and sends them as message to P 01 card.

CONSOLE


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Termination Unit:It provides interface with telephone instruments/other equipments.

The various types of interfaces are:

2-wire subscriber interface

4-wire E&M interface

2-wire centre office interface

30 channel digital interface

There is a unique card for each interface known as LCC card. Each

analog interface card comprises 8 ports and digital interface cardcomprises 30 ports.

Service Unit: It consists of ATD card which is used forannouncement and tones. A

conference card which has a facility to conduct conference of 6

parties.

All subscriber lines and trunks are interfaced to PABX system through the terminalinterface card. The terminal interface card consists of 8 termination ports. Such cards form

a terminal group which is designated as TG.

TG= 4 Terminal cards = 4 X 8 = 32 ports = 32 Channel

2.7 RTU (Remote Terminal Unit)It is one of the most important tools of SLDC. Without this it could not have been

possible to fetch the data from the remote stations and monitor the activities of the

remote stations. RTUs have made it possible to make many of the remote station

man less. They are playing very active role in making day to day availability of data

from the remote stations. One of the RTUs installed at 132 kv sub-station Jutogh at

Shimla is as shown on the next page:

When the RTUs were not devised, most of the potential of PLCC system remained

unutilised. The application of RTUs has made it possible to use the hidden potential

of PLCC in this age of state of Art. Transducers and MODEMs play a very


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important role for the establishment of Real Time Data Acquisition system. This

system is designated with the abbreviation DAS and the whole combination of

making data available in real time operation at SLDC is designated as SCADA i.e.

Supervisory Control And Data Acquisition .RTU is a combination of transducers

used for various measurands such as voltage frequency, MW, MWh, MVARh and

converts electrical signal into digital signal which is further converted into analog

signal using modem if the same is to be transmitted through PLCC system or

otherwise the digital signal is sometimes directly processed without any conversion

if the same is to be transmitted through wideband system In power system there are

two types of measurands. One is analog type and the other is digital type. They are

as under:

0 Analog type measurands: Voltage, frequency, active power, reactive power,

position of auto transformer tap.

1 Digital type measurands: Status of circuit breaker and isolator (close/open)

The fig. Given below shows RTU at 132 KV substation Jutogh


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Fig.16 RTU at 132 KV substation Jutogh

2.8 UPS (Uninterrupted power supply)

1.4.1 Uninterruptible Power Supply

Introduction

Uninterruptible power supply (UPS) is a device that protects electronic equipment from

power uncertainties. A UPS is a device that is interfaced between the electric network

(connected to utility power) and the materials that need protecting.

The UPS allows the materials to be switched to emergency battery power for several

minutes in case of electrical problems, in particular during:
http://en.kioskea.net/contents/protect/onduleur.php3http://en.kioskea.net/contents/protect/onduleur.php3


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Power line disturbances, i.e. a split second power outage that can cause a computerto restart

Power outages, corresponding to a break in the power supply for a given amount oftime

Overvoltage, i.e. a nominal value greater than the maximum value needed for thenormal functioning of electrical appliances

Undervoltage, i.e. a nominal value less than the maximum value needed for thenormal functioning of electrical appliances

Voltage spikes, i.e. high amplitude transient (short-term) overvoltage. These spikesare caused when powerful devices are stopped or started and overtime can damage

electrical components

Lightening, which is a source of extreme overvoltage that occur suddenly duringbad weather (storms)

Most electrical disruptions are tolerated by computer systems. However, sometimes they

can cause data loss and service interruptions and even material damages.

The UPS helps to "smooth out" voltage, i.e. eliminate peaks that are over a certain level.

When there is a power outage, the energy stored in the emergency battery keeps the power

supply flowing to equipment for a small amount of time (normally for 5 to 10 minutes).

Beyond the minutes of autonomy that the UPS supplies, this gained time also allows the

equipment to be switched to other energy sources. Some UPSs can also be directly attached

to the computer (e.g. with a USB cable) so that it can order its own shutting off in case of a

power outage and thus avoid any data loss.

Fig. 17 General Outlook of UPS

Under ULDC scheme(Unified Load Despatch Scheme), the following capacity of UPS

have been installed to provide uninterrupted power supply and to have firm data.

a) At SLDC Shimla: 2 no. UPS each 40 kVA capacity have been installed at SLDC

Shimla. These UPS comprises two types of battery system, i.e. 384 V/200 Ah,

48V/415Ah respectively.

b) At Sub-LDC Hamirpur: 2 no. UPS each 20 kVA capacity have been installed at

SLDC Shimla. These UPS comprises two types of battery system, i.e. 384 V/200

Ah, 48V/415Ah respectively.

c) At Sub-LDC Kunihar: 2 no. UPS each 20 kVA capacity have been installed at

SLDC Shimla. These UPS comprises two types of battery system, i.e. 384 V/200

Ah, 48V/415Ah respectively.


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In addition to above, at each site of SLDC, DG Sets of capacity 75 kVA at SLDC Shimla

and 45 kVA at respective SUB-LDC sites have been provided to have standby arrangement

for uninterrupted supply.

CHAPTER 3 ENERGY MANAGEMENT A "SPECIAL

CASE" OF HIMACHAL PRADESH.

3.1 Introduction

Himachal Pradesh being purely hydro state has surplus during monsoon months

but face acute shortages during winter as availability from hydro Stations reduces to

20 to 25% due to lean discharges and so happens to the Central Sector shares of

Hydro based projects of the region. As HPSEBs committed power is not adequate

to meet the demand as such HPSEBL meets its deficit demand by way of different


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arrangements.

Fig. 18 ABOUT STATUS OF HIMACHAL PRADESH

3.2 Grid Diagram of Himachal Pradesh

7


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Fig. 19 Grid Diagram of Himachal Pradesh

3.3 Modes of Managing Energy Deficits

1, GoHP (Govt. of Himachal Pradesh) free power entitlement in Central sector / Joint

sector projects as well as through GoHP entitlement available within the state.

2. 22% equity power of GoHP in NJPC project.

3. Through Banking arrangements.

4. Unscheduled Interchanges (Over Drawl) transactions under real time operation.


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5. Unallocated quota allotted by Govt. of India during winter months.

3.4 Description of different modes of Power Arrangements

a. Central Sector Projects

HPSEBL receives power from central sector projects in proportion to its

entitlement and is governed under CERC regulation. This power is made

available at generator terminal of the respective projects and is wheeled

through Power Grid system till it is made available at H.P periphery. The bills

in respect of generator comprises two parts . One part is energy availed by

HPSEBL at generator terminal and the other part of the bill is raised by Power

Grid on account of wheeling of power through their system upto H.P

periphery. The quantum of energy which reflects in a monthly bill is based on

the Regional Energy account prepared by NRPC (Northern Regional Power

Committee).

b. Govt. of H.P. free power Entitlement:

Govt. of H.P.has its free power Entitlement in all those projects which have

been commissioned in Himachal Pradesh . This entitlement is on account of

the home state benefits i.e Himachal has sacrificed its potential as well as

benefits of the people. In addition to above entitlement of GoHP free power ,

HPSEBL also receives 22% equity during winter months or extended winter months

which is at the discretion of GoHP and is given to HPSEBL as its first right to

mitigate the shortages during the the said months.

c. Through Banking :

Transaction / procurement of Power through Banking is also one of the modes which

is considered as a cashless transaction and this energy exchange arrangement is on

equal basis i.e. the obligation of HPSEB to return the banked energy is restricted to

the extent to which the energy has been banked with it during the winter months. The

average rate as agreed as per agreements (Unscheduled Interchange rates based on

prevailing grid frequency conditions at that point of time) are kept to account for


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unadjusted quantum at the end of banking cycle. This arrangement facilitates when

there is large variation in demand pattern during winters on account of fluctuating

weather conditions and provides real time operation and facilitates increase or

decrease of quantum with the mutual consent of both the parties without any

financial implications on either party. With the above arrangement the surplus power

available during the monsoon months is returned for meeting the previous year

banking obligations as well as for Advance Banking (contra banking) arrangement

thus facilitates mitigating winter deficits.

d. Unscheduled Interchange (UI):

This does not fall under any category of mode of transaction of power, but

under prevailing grid frequency conditions, power does flow perforce which

also provides additional assistance to mitigate the instantaneous shortage of

power. This perforce transaction of power is regulated as per CERC

regulation on Unscheduled interchange of power issued by Central Electricity

Regulatory Commission from time to time. However, the underdrawl

/overdrawl of power should not exceed the specific limit or otherwise, the

same shall lead to the collapsing of grid. It is also added that any violation

through UI against the prescribed norms shall lead to penalty to theconcerned utility.

e. Transaction of power through energy exchange:

In this mode of transaction of power, the surplus power available on day-

ahead basis is disposed off through exchange on the available rates. Similarly

through this mode, procurement of power is also carried out to meet the

immediate demand of shortages.

f. Sale/ purchase of power through Tendering process:

In this mode of transaction, bids are invited from different utilities for their

participation in the tendering process and the bidder who qualifies the desired

terms and conditions is given order for supply of power.

3.5 HPSEBL Share in different Projects

HPSEBL receives power throughout the year from the following projects against itsSOR(State of Region Share) share as shown in table below.


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Table-1

Sr.

No. Name of Stations Installed HPs share

capacity % MW

MW (Mega

Watt.)

A.

HPSEBL

Entitlement

I.

BBMB

STATIONS

Bhakra old HP FIXED

10.00

(1.2LU/Day)

Bhakra complex 1478.73 7.19 84.23

Dehr 990.00 7.19 56.83

Pong 396 7.19 11.77

Bhakra (Old) Fixed

10.00

(1.2LU/Day)

II.

NHPC

STATIONS

Chamera-I 540.00 2.90 15.66

Tanakpur 94.20 3.84 3.62

Salal 690.00 0.99 6.83

Uri 480.00 2.71 13.01

Chamera-II 300.00 3.67 11.01

Chamera-III 231 4.36 10.06

Dhauliganga 280.00 3.57 10.00

III. NTPC


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PROJECTS

Rihand-I 1000.

Documents

Major Report on Energy Mgt