Challenges in the Indian
Electricity utility industry
Anjuli Chandra Director – CEA
15th October’08
Sub-transmission and Distribution system at end of
Xth plan
Unit At the beginning of X Plan i.e. April
2002
Achievements during X
plan
At the end of X Plan i.e.
March 2007
DISTRIBUTION LINES
33/22 KV Ckm 288226 26853 315079
11 KV Ckm 1758068 369833 2127901
LT Ckm 3679596 481150 4160746
Total Transmission Line Ckm 5725890 877835 6603725
SUBSTATIONS
33/11 KV MVA 117333 56058 173391
11/0.4 KV MVA 176026 84054 260080
Total- MVA MVA 293359 140112 433470
Sub-transmission and Distribution system at end
of Xth plan
Unit At the beginning of X Plan i.e. April
2002
Achievements during X
plan
At the end of X Plan i.e.
March 2007
SERVICE CONNECTIONS
Domestic Installations Nos.93047342 22139963 115187305
Commercial Installations Nos. 12751299 3652514 16403813
Industrial Installations Nos. 2626715 133415 2760130
HT Nos. 52561 18508 71069
LT Nos. 2574154 114908 2689062
Public Lighting Nos. 447972 121519 569491
Agriculture Nos. 13141378 824828 13966206
Total- Connections Nos. 122014706 26872238 148886944
Metering Status in the country
No. of Consumers 1488 lakh
No. of metered consumers 1242 lakh
Percentage metering 88%
No. of 11 kV feeders 86614
No. of 11 kv feeders metered 84831
Percentage metering 98%
Metering Status in the country
No. of Distribution Transformers 246165
No. of Distribution transformers metered 319866
Percentage metering 13%
Challenge in metering
� Unmetered consumers mostly flat rate and agricultural consumers
� Agriciltural consumers 1.4 crore
� States taking time to install meters on these consumes
� Difficulty in reading these meters as these are geographically spread out
� Another 11-12 crore meters to be installed in 11th plan
Genco
Transmission
Distribution
Customer
Old structure CPRI
New structure in Deregulated Environment
GencoGencoGencoGenco
Customer
DiscomDiscomDiscom
Open access inTransmission
Traders
Open access in Distribution
Traders
CustomerCustomer
ISO
SO
RO
GencoGencoGencoGenco GencoGencoGencoGenco
Requirements in liberalised markets
� To be able to unambiguously identify all data and to allow selected access to application relevant portions of the data.
� The customer base of suppliers becomes heterogeneous and geographically widespread.
� Need for interoperability by using standard interfaces.
� Use of various communication media.
CPRI
Requirements of Market liberalisation
contin…
� Metering data carries strategic competition information and becomes valuable merchandise.
� Metering data not only used for billing purposes but for various other applications.
� Need for mechanisms to control the access to meter data and to make data available according to well defined access rights.
� Need for enhanced data security mechanisms.
CPRI
Data transport
� Data Exchange involves communication between the various meters and the base computer system using relevant protocols.
� Download through CMRI/ AMR into usable format
� Communication capability via various communication mediums
� Radio(UH/VHF/Microwave)� GSM/GPRS/CDMA� PSTN/Leased Line,/ISDN� Wireless Ethernet� VSAT,PLCC, Fibre Optic
Difficult in AMR implementation in India
� Electronic meters installed are of different make and from different manufacturers.
� These meters work on propriety communication protocols.
� Over the years a number of metering protocols have come to be existent in the Indian market.
Difficult in AMR implementation in India
� These are namely the older IEC 61107, the ANSI Standard c12.18, the PACT protocol, Modbus protocol
� The data down loaded from these meters is in different data formats. Therefore, it makes it difficult for utilities to utilize data as it is for billing, load analysis, revenue protection and other purposes.
� Communication protocol is a major issue for implementing AMR in India.
Solutions for interoperability
� To allow seamless integration of the data between various electronic meters the following two solutions are under consideration
� Application Programme interface API software for each make/ type of electronic meters to furnish data in the desired format. (MIOS)
� Adoption of non proprietary/ standard/open common communication protocol by all the meters to give data in the same format.
MIOS
� Meter manufacturers have got together under the banner of MIOS-IEEMA and nine meter manufacturers have developed their API’s which are ready for testing
� Capital Power Systems Limited � Easun Reyrolle Limited� ECE Industries Limited� Elster� Genus� HPL Socomec� L&T� Omni Agate� Secure Meters Limited
MIOS –The Concept
Meter(Has an internal
language)
PC Application software
(Runs on a powerful operating system)
Convert to PC’s language (Protocol)
Meter(Has an internal
language)
PC Application software
(Runs on a powerful operating system)
Convert to PC’s
language(API)
Protocol
CDF
MIOS Model
Protocol Model
MIOS is like a Driver in a Printer.
You can connect any Printer to Your PC following
any Protocol provided you have the driver
MIOS System Architecture
Media
Mfr 01 API #3
Mfr 02 API #1
Mfr 01 API #1
Com
mon D
ata exchange form
at (XM
L)
Software Applications
•Billing•Revenue protection•Tariff design•Engineering analysis•Load profile analysis etc.
HHU(CMRI)
Mfr 01 API #2
Mfr 02 API #2
Mfr 01 API #2
Proprietary format
Open Protocol
� ANSI C 12.19-1997 �
� Modbus Standard
� IEC 62056 /DLMS
� PACT protocol
Strategy for implementation
� Approach should address :
� Legacy meters
� Future meters
� Matter under consideration in CEA and MoP
Accuracy of meters
Accuracy meters to be installed forvarious categories of consumers
� Interface meter- class 0.2S
� Consumer meter- class 1 or better
� Energy accounting and audit meter- class 0.2 S
Value of Current for direct connected
meters
Power Factor Percentage Error Limits for
Meters of Class 1.0
0.05 Ib ≤ Ib ≤ 0.1 Ib 1 ±1.5
0.1 Ib ≤ Ib ≤ IMAX 1 ±1.0
0.1 Ib ≤ Ib ≤ 0.2 Ib 0.5 lagging0.8 leading
±1.5±1.5
0.2 Ib ≤ Ib ≤ IMAX 0.5 lagging0.8 leading
±1.0±1.0
When specially requested by the user :
From 0.2 Ib to Ib
0.25 lagging0.5 leading
±3.5±2.5
Accuracy of consumer meters under various conditions as per IS 13779
Error % of meters showing error on Positive side(+)
% of meters showing error on Negative side(-)
Percentage CumulativePercentage
(1) (2) (3) (4)=(2)+(3) (5)
0 - 0.5% 19.91 10.77 30.68 30.68
0.51-1.0% 23.35 5.81 29.16 59.84
1.01-2.50% 26.64 4.75 31.39 91.23
2.51-3.0% 0.6 0.2 0.8 92.03
>3% 3.88 4.09 7.97 100
Total 74.38 25.62 100
Tests conducted at site by the utilities in ‘07
0
1000
2000
3000
4000
5000
6000
>-3% -2.51 to -3 %
-1.01 to -2.5%
-.51 to -1%
0 to -.50%
0 to 0.5%
.51 to 1%
1.01 to 2.5%
2.51 to 3%
>3%
Fre
quen
cy
Accuracy of consumer energy meters three Phase (JVV NL, Jaipur)
2007-09
Accuracy of consumer energy meters Single Phase (JV VNL, Jaipur)
0
10000
20000
30000
40000
50000
60000
70000
>-3% -2.51 to-3 %
-1.01 to-2.5%
-.51 to -1%
0 to -.50%
0 to0.5%
.51 to1%
1.01 to2.5%
2.51 to3%
>3%
Fre
quen
cy
2007-09
Accuracy of consumer energy meters (GESCO, Karnatak a))
0
50
100
150
200
250
300
<-3% -2.51 to-3 %
-1.01 to-2.5%
-.51 to -1%
0 to -.50%
0 to0.5%
.51 to1%
1.01 to2.5%
2.51 to3%
>3%
Fre
quen
cy
2007-08
2008-09
Accuracy of consumer energy meters (NDPL)
0
200
400
600
800
1000
1200
1400
1600
1800
2000
<-3% -2.51 to-3 %
-1.01 to-2.5%
-.51 to -1%
0 to -.50%
0 to0.5%
.51 to1%
1.01 to2.5%
2.51 to3%
>3%
Fre
quen
cy
2007-08
2008-09
Accuracy of consumer energy meters (DPSC 1 class)
0
2
4
6
8
10
12
14
16
<-3% -2.51 to-3 %
-1.01 to-2.5%
-.51 to -1%
0 to -.50%
0 to0.5%
.51 to1%
1.01 to2.5%
2.51 to3%
>3%
Fre
quen
cy
2007-08
2008-09
Accuracy of consumer energy meters (DPSC 0.5 class)
0
50
100
150
200
250
300
<-3% -2.51 to-3 %
-1.01 to-2.5%
-.51 to -1%
0 to -.50%
0 to0.5%
.51 to1%
1.01 to2.5%
2.51 to3%
>3%
Fre
quen
cy
2007-08
2008-09
Accuracy of consumer energy meters (NEESCO, Orissa)
0
50
100
150
200
250
300
<-3% -2.51 to-3 %
-1.01 to-2.5%
-.51 to -1%
0 to -.50%
0 to0.5%
.51 to1%
1.01 to2.5%
2.51 to3%
>3%
Fre
quen
cy
2007-08
2008-09
Accuracy of consumer energy meters (Tata Power)
0
100
200
300
400
500
600
700
800
900
<-3% -2.51 to-3 %
-1.01 to-2.5%
-.51 to -1%
0 to -.50%
0 to0.5%
.51 to1%
1.01 to2.5%
2.51 to3%
>3%
Fre
quen
cy
2007-08
2008-09
Influencing parameters in the field conditions affecting accuracy
� The various influencing parameters in the field condition which may effect the accuracy of the meter either in positive direction or negative direction are
� Voltage
� Frequency
� Temperature
Influencing parameters in the field conditions affecting accuracy
� Power Factor
� Current / load flown to the meter
� Nature of the load – fluctuating/ steady
� Harmonics
Effect of various parameters
Sl.No. Influence Parameter
Standard condition
Variation allowed as per IS13779-99
Field condition
Effect on Meter Accuracy (Theoretical)
1. Temperature 27 deg C 0.05 per deg C
37 deg C approx
0.5 %
2. Frequency 50 Hz 0.8 with 5 % variation
49 Hz approx
0.32%
3. Voltage variation
240Volts 0.7 with 10 % variation
220 V approx
0.7%
Influencing parameters in the field conditions affecting accuracy
� If we take contribution / effect on accuracy of various parameters in combination and in both direction i.e positive or negative in reference to standard test condition, in that case there are more than 1000 combinations to be tested to find out performance of one type of meter of a particular make under field conditions on various permutations and combinations of influencing factor.
Influencing parameters in the field conditions affecting accuracy
� In case there are different types of meter and different makes then this need to be multiplied by as many combinations i.e. for two makes and two types of meter of each make, we need to have 4 x more than 1000 combinations.
� This is a very cumbersome and time consuming exercise.
Method of testing and meter test
equipments used for testing accuracy
� The test method for field testing is not standardised. There is a need of standard test procedure to test and maintain the test equipment under site condition
� Reference meter are generally installed on load side. Being an electronic device it also act as load (although very small say 8VA/ 3W) but even due to this load DISCOM meter read more than Reference standard. This factor will be sizeable if consumer test load is low.
Method of testing and equipments
used for testing accuracy
� The Meter test Equipment performance under site conditions is not defined so the MTE error is also influenced under site condition therefore there is a need of standard for MTE.
� The testing equipment used in the field for testing of direct connected meters consists of Clamp on CTs, Leads/Wires, Portable Reference Meter and the overall accuracy of this whole set up is in the order of ± 0.5% under normal / reference conditions.
Method of testing and equipments
used for testing accuracy
� Limitation of this set up in the field is that the clamp on CT is not fully closed due to either dust particles between the contact, Carbon deposited between the contacts, poor spring performance, or clamp-on CT not closed properly because of any other reason.
� All these conditions will amount to clamp on CT not closed fully and this will lead to high positive error as the current measured by clamp on CT would be less than the actual current flowing in the meter,
Thank You