Module PS5 Rev 1

Substation Engineering

J.D.PARMAR

NIHAR RAJ

24th & 25th August 2007

[email protected]

[email protected]

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

2 -

Substations

Introduction Various Switching Configuration Interlocking & Protection

philosophy Basics of layout engineering Substation design calculation Equipment & accessories Interface requirement of control,

protection & SCADA Statutory requirements & Safety

in substation

Content

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

3 -

Substations

Introduction

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

4 -

Substations

What is Substation ? Substation is an Electrical installation

where power is controlled for transmission & distribution purpose.

Substations can be categorized as: Power evacuation substation

Substation part of Transmission system

Substation part of Distribution system

Introduction

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

5 -

Substations

Introduction : The Electric UtilityIntroduction : The Electric Utility

Power Evacuation Substation

Transmission Substation

Switching Substation

Distribution Substation

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

6 -

Substations

Located adjacent to the Power Plant Preferred voltage level

420 kV 245 kV 123,145 kV 72.5, 66 kV

Evacuation voltage level depends on Quantum of power to be evacuated (size of

power plant) Distance of Transmission Gird network voltage of surrounding

transmission system Normally built by

Utilities (e.g. NTPC, NHPC, Captive Power Plant by industries)

Independent Power Producer (IPP)

Introduction : Power Evacuation substation

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

7 -

Substations

Location is decided based on Transmission Grid Network

Preferred voltage level 420kV

245kV

145kV

Transmission voltage depends on Quantum of power to be received / transmitted

Length of transmission line

Normally built by Utilities (e.g. Power Grid, State Electricity

Boards)

Introduction : Transmission substation

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

8 -

Substations

Location is near the load Preferred voltage level

245kV

145kV

72.5/36 kV

Station voltage level depends on Demand of power

Utility norms of distribution Normally built by

Utilities (e.g. State Electricity Broads)

Industries

Introduction : Distribution substation

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

9 -

Substations

SwitchingConfiguration

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

10 -

Substations Switching Configuration

What is Busbar configuration ? Busbar configuration or Bus switching scheme

is the circuit adopted for substation based on following: System reliability Operational flexibility Ease of maintenance Limitation of fault level Simplicity of protection system Ease of extension Avaibility of land Cost

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

11 -

Substations

With Sectionaliser

Switching Configuration : Single Bus Scheme

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

12 -

Substations

Without Sectionaliser

With Sectionaliser

Switching Configuration : Single Bus Scheme

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

13 -

Substations Switching Configuration: Single Bus Scheme

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

14 -


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

15 -

Substations Switching Configuration : Bus Sectionalizer

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

16 -


Application Industrial stations with voltage level

generally up to 145kV

Also used for 245kV station with 2/3 bays

Features Simple system

Ease of Operation & maintenance Single level bus layout Easily expandable

Very simple Control & Protection philosophy

Large saving in space

No redundancy

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

17 -

Substations

Double Bus with two Main & without

Transfer

Double Bus with one Main & one Transfer

Double Bus with one Main & one Main cum Transfer

Switching Configuration: Double Bus Scheme

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

18 -

Substations Switching Configuration : One Main & Transfer

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

19 -


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

20 -


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

21 -

Substations Switching Configuration : Main & Main cum transfer

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

22 -


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

23 -


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

24 -

Substations Switching Configuration : Double Main

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

25 -

Substations Switching Configuration : Double Main

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

26 -

Substations Switching Configuration : Double Main with bypass

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

27 -

Substations Switching Configuration : Double Main with bypass

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

28 -

Substations

Bus Coupler Bay

Switching Configuration:Application of Transfer Bus

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

29 -


Application Normally this is used for most industrial

stations and some time small power evacuation system

Features Simpler system

Better availability as additional bus is provided

Breaker can be taken out for maintenance where transfer bus feature is provided

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

30 -

Substations

Three Bus with Main I & II and separate Transfer Bus

Main-1

Main-2

Transfer

Switching Configuration: Three Bus Scheme

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

31 -

Substations

Main-1

Main-2

Transfer


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

32 -

Substations Switching Configuration : Three Bus

Main Bus#1 Main Bus#2 Transfer Bus

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

33 -

Substations Switching Configuration : Three Bus

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

34 -

Substations Switching Configuration : Three Bus (Bus Coupler)

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

35 -

Substations Switching Configuration : Three Bus (Bus Transfer)

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

36 -

Substations

Application Power evacuation station

Interconnecting substation for transmission lines

Heavy Industrial stations viz. Steel, Aluminium, Petro-chemicals

Features Independent two buses sharing the feeder

Better load management

Better reliability

One transfer bay is in-built for redundancy of one bay

Complex Control & Protection system


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

37 -

Substations

Main-1Main-2

Switching Configuration: One & Half CB Scheme

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

38 -

Substations

Main-1Main-2


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

39 -

Substations Various Busbar Configuration : One & Half CB Scheme

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

40 -

Substations

Application Mostly this configuration is adopted where high

reliability is required

Power evacuation station for big power plant

Interconnecting transmission substations with 420/245kV level

Features Very high reliability

Costly because of increase no. of Circuit Breaker

Complex Control & Protection philosophy


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

41 -

Substations Switching Configuration : Application

Power Generating Stations Double Bus Scheme Three Bus scheme

Two main & one transfer

One & Half CB Scheme Transmission Stations

Double Bus scheme Main & Main cum transfer

Three Bus scheme Two main & one transfer

One & Half CB Scheme

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

42 -

Substations Switching Configuration : Application

Distribution Stations Single Bus scheme Single Bus with sectionalizer Double Bus scheme

Main & transfer

Double Main & Transfer (Industrial customer)

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

43 -

Substations

EngineeringCalculations

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

44 -

Substations Engineering Calculations

Purpose of doing engineering calculation To establish & validate design To Optimize To give complete error free solution to

customer. To ensure safety

Of Persons Of Animals Of equipments

To ensure correct Power system operation

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

45 -


Reference Used by ABB for doing Calculations IEC Standards IEEE Standards IS Standards CBIP International papers

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

46 -


Different types of calculations done in switchyard engineering1. Short Circuit Force Calculation for Flexible conductor2. Short Circuit force calculations for Rigid conductor 3. Cantilever strength check for bus support insulators4. Wind Pressure calculation5. Temperature rise calculation for Flexible conductor6. Temperature rise calculation for Rigid conductor7. Earthing Calculation8. Shielding Calculation9. Sag Tension Calculation10. Battery sizing calculation

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

47 -

Substations

ELECTRICAL CONNECTION

FLEXIBLE RIGID

TENSILE FORCE ( Ft)

DROP FORCE ( Fs)

PINCH FORCE ( Fpi)

FORCE AT RIGID END(Fda)

FORCE AT FLEXIBLE END(Fdb)

Engineering Calculations : EDF

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

48 -

Substations Inputs for Calculation

Short Circuit Force for Flexible conductor

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

49 -

Substations Engineering Calculations : EDF

PURPOSE :- TO FIND OUT THE MAXIMUM SHORT CIRCUIT

FORCE COMING ON THE EQUIPMENT TERMINAL.

TO FIND OUT THE CANTELIVER STRENGTH OF THE BUS POST INSULATOR.

TO EVALUATE THE FORCES FOR DESIGN OF CIVIL AND STRUCTURE.

FACTORS/INPUTS ON WHICH EDF DEPENDS:- TYPE OF CONDUCTOR ( FLEXIBLE OR RIGID

CONDUCTOR)

SHORT CIRCUIT CURRENT.

FAULT CLEARANCE TIME.

SPAN LENGTH.

PHASE DISTANCE.

NUMBER OF CONDUCTOR PER PHASE.

STATIC TENSION.

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

50 -

Substations Engineering Calculations : Earthing

PURPOSE :- TO FIND OUT THE MAXIMUM STEP AND

TOUCH POTENTIAL COMING IN A SUBSTATION.

TO ACHIEVE SAFE VALUES OF STEP AND TOUCH POTENTIAL WRT TO THE CALCULATED VALUES.

TO ACHIEVE SAFE VALUES OF GPR BY RESTRICTING THE REDUCING THE VALUE OF GROUND RESISTANCE.

FACTORS/INPUTS ON WHICH EARTHING DEPENDS:- SHORT CIRCUIT CURRENT.

FAULT CLEARANCE TIME.

SOIL RESISTIVITY.

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

51 -

Substations Engineering Calculations : DSLP

PURPOSE :- TO PROTECT SUBSTATION FROM

LIGHTNING STROKE BY PROBABLISTIC METHOD.

FACTORS/INPUTS ON WHICH DSLP DEPENDS:- HEIGHT OF LIGHTNING MAST/SHIELD WIRE.

HEIGHT OF THE EQUIPMENT TO BE PROTECTED.

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

52 -

Substations

What are the methods for D.S.L.P. design? As per "High Voltage Engineering" by Razevig with help of LM

As per IS:2309 which is also using LM and spikes

As per electro-geometry method by using combination of LM and shield wire.

Protective Zone by LMShield wire

Lightning Mast

Typical DSLP Layout

Engineering Calculations : DSLP

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

53 -


Shielding Calculation

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

54 -

Substations

Substation Engineering CalculationEngineering Calculations : DSLP

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

55 -

Substations Engineering Calculations : Sag Tension

PURPOSE :- TO STRING THE CONDUCTOR AT MAIN BUS LEVEL

AND JACK BUS LEVEL. TO MAINTAIN NECESSARY ELECTRICAL

CLEARANCES. FOR PANTOGRAPH ISOLATORS TO ACHIEVE A

PROPER CONTACT AREA BETWEEN THE HANGER AND THE PANTOGRAPH ARM.

FACTORS/INPUTS ON WHICH SAG TENSION DEPENDS:- STATIC TENSION SPAN OF CONDUCTOR, TYPE & NUMBER OF

CONDUCTOR. MAXIMUM AND MINIMUM TEMPERATURE. WIND PRESSURE. WEIGHT OF STRING HARDWARE, INSULATOR

STRING, SPACERS.

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

56 -


Sag Tension Calculation

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

57 -

Substations Engineering Calculations : Wind Pressure

PURPOSE :-

TO EVALUATE THE WIND PRESSURE AT VARIOUS LEVELS.

WIND PRESSURE FORMS INPUT FOR STRUCTURE AND CIVIL DESIGN.

WIND PRESSURE CALCULATION IS ALSO USED FOR DETERMINING CANTELIVER STRENGTH OF ALL INSULATORS (ALONG WITH EDF FORCES)

STANDARDS USED ARE IS:802 AND IS:875

FACTORS/INPUTS ON WHICH WIND PRESSURE CAL DEPENDS:- WIND ZONE IN WHICH A SUBSTATION IS

SITUATED.

TOPOGRAPHY NEAR THE SUBSTATION.

LOCATION OF CLIFF, VALLEY OR MOUNTAIN NEAR A SUBSTATION.

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

58 -

Substations Engineering Calculations : Temperature Rise

PURPOSE :-

To determine thermal sizing of conductors ( Flexible Conductor / AL.Tube)

FACTORS/INPUTS ON WHICH TEMPERATURE RISE CAL DEPENDS:- Continuous current.

Short Circuit Current.

SOLAR HEAT GAIN.

RADIATION LOSS.

CONVECTION HEAT LOSS.

FAULT DURATION TIME.

AMBIENT TEMPERATURE.

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

59 -


Temperature rise calculation for Flexible Conductor

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

60 -


Temperature rise calculation for Rigid Conductor

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

61 -

Substations Engineering Calculations : Temperature Rise

PERMISSIBLE VALUES OF OPERATING TEMPERATURE :- Maximum allowed temperature rise under

normal condition. ACSR Conductor = 75deg C (As per CBIP

Manual) Al. Tube = 85 deg C ( BS:159)

Maximum allowed temperature under short circuit condition. ACSR Conductor = 650 deg C ( As per CBIP

paper) Al tube = 200 deg C ( As per IEEE:605)

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

62 -

Substations

Layout Engineering

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

63 -

Substations Layout Engineering

What is Substation Layout ?

Substation Layout is the conception which transforms to reality through engineering, execution & commissioning.

Layout Engineering . . . . is the basic document to be sent to Customer /

Consultants for approval

forms the basis of entire project scope

forms basis for engineering estimates

form input for civil & structure design

basic document for statutory approval

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

64 -

Substations

TYPICAL SUBSTATION PLAN LAYOUT

Incoming Line Bay Single Bus Bar Outgoing

Transformer Bay

Layout Engineering : Plan View

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

66 -


Following details form the input for layout engineering: Bay & Busbar configuration

Bay width & depth, Height of busbar, Distance to fence, Building and total dimensions.

Statutory clearances (Phase to Phase, Phase to Earth, Sectional clearance)

Lightning Mast, Gantries (Column & Beam), String Insulators, Busbar, Equipment etc.

Position of various drive box, junction box, Marshalling box.

Maintenance aspect for Transformer, Reactor, CB.

Illumination requirement.

Calculations like EDF ( deciding max safe span length& location of BPI) , DSLP (locating LM).

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

67 -


Bay Width will depend on . Phase to Phase & Phase to Earth clearances Sectional Clearances Tower width Swing of conductor Bird clearances Cable trench routing Maintainability of equipment Tandem Isolator arrangement

Distances in between equipment will depend on.. Phase to Phase & Phase to Earth clearances Sectional Clearances

Position of switch cubicle, junction box, drive box etc.

Maintainability of equipment

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

68 -


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

69 -

Substations

Standard bay width & clearancesSystem Voltage

Phase to Phase Distance

Phase to Earth Distance

Bay width Sectional Clearance

kV mm mm mm mm66 2000 2000 8000 3000

132 2700 2500 9400 3500

132 (Standard)

3000 3000 12000 3500

220 (standard)

4500 4000 17000 4500

220 (Industry)

4500 4500 18000 4500

220 (IPP) 5000 4000 18000 4500

400 7000 6500 27000 6000

Layout Engineering

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

70 -


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

71 -

Substations

Equipment &Accessories

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

72 -

Substations

Substation

Main Equipment

Engineered items

Auxiliary Equipment

Civil

Auxiliary System

Structure

Main Equipment

Equipment & Accessories

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

73 -

Substations

Main Equipment Circuit Breaker Instrument Transformer (CT/CVT) Surge Arrester Isolator Transformer & Reactor Bus Support Insulator Line Traps Control & Protection system Power Line Carrier Communication system


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

74 -

Substations

72.5 kV EDF Breaker

420 kV ELF SP Breaker

72.5 kV EDI Breaker

245 kV ELF SP Breaker

420kV, 50kA type ELF SP 6-2

245kV, 40kA type ELF SP 4-1

245 kV, 40 kA type LTB E1

145kV, 40kA type LTBD1

72.5kV, 31.5kA type ED

245 kV LTB E1 Breaker


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

75 -

Substations

Outdoor live tank vacuum & SF6 circuit breakers 3.3kV to 40.5kV Spring and magnetic actuator mechanism (12/15kV)

Single pole vacuum circuit breakers and interrupters with magnetic actuators for 25kV AC railway traction applications


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

76 -

Substations

PRODUCT RANGEDead Tank Current Transformers 66-420 kVCapacitor Voltage Transformers 72.5-420 kVCoupling Capacitors 72.5-420 kVGrading Capacitors Up to 280 kV


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

78 -

Substations

Types of Isolator

Center Break

Double Break

Vertical Break-knee type

Voltage 11kV - 800kV Op. Mech. Motor / Manual Current 100-3150A STC 40kA Earth Switch 1, 2, Independent Orientation Series / Parallel / Tandem


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

79 -

Substations

Power transformers / Converter Transformer/ Traction Transformer Used of conversion of energy from one

voltage to another voltage level Costliest equipment in substation Single phase & three phase installation For major substations tertiary being

loaded for feeding auxiliary power to substation

Oil & paper as insulating material prevails Use of High Temperature

Superconducting (HTS) material FEM based tools for design analysis


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

80 -

Substations

Bus Support Insulators are used for supporting the busbars

Important selection parameters Voltage level

Canteliver strength

Creepage distance

Top & Bottom PCD

Compressive strength

Torsional strength


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

81 -

Substations

Line traps are used for Power system communication

It blocks high frequency carrier signals Important selection parameters

Voltage level

mH rating

Continuous current rating

Short Circuit current rating

Type of mounting Pedestal Suspension


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

82 -

Substations

Control & Protection System Used for controlling flow of power Advent of 61850 based relays Mounting of panels in outdoor AC

Kiosk New trend started by PGCIL First Kiosk drawing conceptualised by

ABB DESIGN


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

83 -

Substations

Substation

Main Equipment

Engineered items

Auxiliary Equipment

Civil

Auxiliary System

Structure

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

84 -

Substations

Engineered Items Busbar Materials

Strung bus conductor (ACSR) Rigid bus conductor (AL Tube) Clamps & Connectors String Insulator & Hardware

Earthing Materials Main earthing materials (Rod or Flat) Earth Pits

Cables & accessories LT Power & Control cable HT Power Cable Cable terminations, gland, lugs, ties, marker

etc. Cable supporting materials


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

85 -

Substations

Types of Busbar

Rigid bus comprising of AL tube

Strung bus comprising of A C S R / A A A

conductor

Types of Support

Bus post insulator for rigid bus

String Insulator for strung bus

Component & Accessories

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

86 -

Substations Equipment & Accessories

Expansion type terminal Connector

Tee - Connector

Terminal Connector

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

87 -


Bus Support Insulator Clamp

Tee Connector

PG Clamp

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

88 -


Hardware Material

Double Tension String Hardware

Tension Clamp & Arcing Horn

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

89 -


Drop Clamp & Through Clamp

Single Suspension String Hardware(Drop type & Through type)

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

90 -

Substations

Substation

Main Equipment

Engineered items

Auxiliary Equipment

Civil

Auxiliary System

Structure

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

91 -

Substations

Auxiliary Equipment LTAC Switchgear Panel DC Distribution Board Battery & Batter Charger DC Distribution Board Auxiliary LT Transformer Lighting Transformer Main Lighting distribution transformer Emergency lighting distribution transformer Diesel Generator UPS


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

92 -

Substations Equipment & Accessories : LT AC Distribution

50V BATTERY CHARGER

FIRE FIGHTING SYSTEM

415V ACDB-2A

415V MAIN SWDB-1A

LIGHTING DB-3A

EMERGENCY LIGHTING DB-

4A

100KVA LIGHTING TRAFO.

VENTILATION DB-5A

220V BATTERY CHARGER

630KVA AUX. TRAFO. 1000KVA AUX. TRAFO.

250KVA DG SET

415V AC AUXILIARY

SYSTEM

33KV FORM TERTIARY OF 315MVA TARNSFORMER

11KV FROM S.E.B.

Typical AC System SLD

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

93 -

Substations Equipment & Accessories : AC & DC Board

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

94 -

Substations

DC Auxiliary System Auxiliary system which provides reliable DC source for

control & protection circuit of substation equipment. DC system backed up by Battery ensures higher level of security over AC auxiliary system

Typical DC Load in substation Protection & interlocks

Switchgear control

Remote control & Indication

Annunciation system

Control & instrumentation

Power line carrier ( PLCC )

Emergency DC Lighting

Electric clocks

Communication systems

Data acquisition & logging system

Equipment & Accessories : DC System

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

95 -

Substations Equipment & Accessories : DC System

Tubular Battery Battery is simple construction Life is 10 years. Most Economical

Plante Battery 40% better performance Longer Life (20 years) Almost 2.5-3 times Costlier than Tubular battery

Maintenance Free Does not require any topping up of water Less hazardous and no special room required Needs control environment at 270C Cost is 2 times of Tubular battery

Ni-Cd Battery Longer life span (25 years) More stable & reliable performance Less hazardous and corrosion free Cost is 4 times of tubular battery

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

96 -

Substations

Inputs for Battery Sizing

Instantaneous or Momentary Load

Circuit Breaker Trip / Close, Protective Relays

Continuous Load

Annunciation system, DC supervision, Indication

Lamps, Auxiliary Relays, Semaphores

Emergency Loads

Emergency lighting

Equipment & Accessories : DC System

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

97 -


BATTERY SIZINGMaximum allowable battery voltage(V) = 254Minimum allowable battery voltage(V) = 199Float voltage (minimum)(V) = 2Float voltage (maximum)(V) = 2.28Minimum allowable cell voltage(V) = 1.80No. of cells = min.allowable battery voltage/end of discharge cell voltage = 199/1.8= 110.56

No of cells selected = 111

Minimum Battery voltage at end of discharge= 111*1.8V= 199.8Maximum Battery voltage = 111*2.28V= 253.08Nominal battery Voltage = 111*2.0V= 222

Electrolyte temperature = 19 Deg. Celsius

Sr. No. System/Loads 0-1min. 1-179min. 179-180min.

1 Sub Total for 400kV Swgr. System (sheet 4 of 13) 61.995 1.995 1.9952 Sub Total for 33kV swgr system (sheet 6 of 13) 6.205 0.295 1.2053 Sub Total for 415V main system (sheet 8 of 13) 8.102 1.157 1.1574 Sub total for 415V valve cooling (sheet 11 of 13) 5.041 2.586 2.5865 Sub total for 415V DG swgr (sheet 11 of 13) 1.511 0.193 0.1936 Sub total for 415V fire fighting system (sheet 11 of 13) 0.155 0.155 0.155 LOAD CYCLE :7 Sub total for 415V water system (sheet 11 of 13) 0.123 0.123 0.1238 Sub total for 415V AC/vent. system (sheet 11 of 13) 2.743 0.107 0.1079 0-1min. 120.114

10 Em. Lighting Load (sheet 13 of 13) 18.182 18.182 18.182 1-179min. 39.53211 Sub Total for MACH2 system (sheet 12 of 13) 14.545 14.545 14.545 179-180min. 40.44112 Sub Total for Key interlock system(sheet 12 of 13) 13 Sub total for emergency swgr (sheet 9 of 13) 1.511 0.193 0.193

Total (=1+2+3+4+5+6+7+8+9+10+11+12+13) = 120.114 39.532 40.441

PERIOD LOAD (AMP.)

BATTERY LOADING DIAGRAM

179-180min.1-179min.0-1min.

0

25

50

75

100

125

150

175

200

TIME

LOA

D IN

AM

PS

0-1min.

1-179min.

179-180min.

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

98 -


Period Load (Amperes) Change in load (Amperes) Duration of Period (minutes)

Time to End of Section (minutes)

K Factor

Required section size

(Curve) Pos. Value Neg. Value

(CA) (K)(IF CA>0,

POS=CA*K)(IF CA

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

99 -


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

100

-Substations

Substation

Main Equipment

Engineered items

Auxiliary Equipment

Civil

Auxiliary System

Structure

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

101

-Substations

Auxiliary System Illumination system

Indoor (Control Room, FFPH, Kiosk)

Outdoor

Fire fighting system HVWS system

Nitrogen injection

Air conditioning system


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

102

-Substations

Fire Fighting System Fire fighting

Fire Water Storage Tank Fire Water Pumping System Hydrant System High Velocity Water Spray System Portable Fire Extinguishers CO2 Gas Extinguishers

Fire detection Thermal Heat Detectors Ionization Smoke Detectors Photoelectric Smoke Detectors Response Indicators Manual Call Points Hooters Fire Alarm Panel


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

103

-Substations

Equipment & Accessories : P & I Diagram

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

104

-Substations

Equipment & Accessories : Fire Fighting Building

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

105

-Substations

Equipment & Accessories : Fire Fighting Building

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

106

-Substations

Equipment & Accessories : Hydrant System

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

107

-Substations

Equipment & Accessories : HVWS System

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

108

-Substations

Equipment & Accessories : HVWS System

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

109

-Substations

Equipment & Accessories : N2 Injection

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

110

-Substations

Separate AC System for Control room / Other areas

Ventilation System Other Areas, Valve Hall

AC System 100% Standby AC - Chilled Water System / Split Units Ventilation with Humidity Control

Equipment & Accessories: Air Conditioning System

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

111

-Substations

Lighting system for substation are considered as:

Normal AC to cater lighting requirement during normal operating condition

Emergency lighting on failure of normal AC lighting source

DC emergency for illuminating strategic locations

Lighting from DG system for bigger substations

Outdoor Lighting

Building Lighting Fire fighting building Control room building

Kiosk Lighting

Street Lighting

Equipment & Accessories : Illumination System

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

112

-Substations

Equipment & Accessories : Illumination System Illumination level required for substation is.

Lighting shall provide enough light depending on nature of work to be carried out. Operational lighting as per IS:3646 part-III.

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

113

-Substations

Outdoor Illumination System High Pressure Sodium Vapour (HPSV) luminaries

with various combination of rating with high beam & narrow beam used to achieve desired illumination

Ratings usually considered

2X400W HPSV, 1X400W HPSV for switchyard and outdoor equipment

2X250W HPSV, 1X250W HPSV for switchyard and outdoor equipment

1X150W HPSV for street lighting

High Pressure Mercury Vapour / Halogen luminaries are also taken if they specifically required by customer


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

114

-Substations

Indoor Illumination System Indoor illumination is achieved by various types of

luminaries according to the requirement and utility of various rooms.

Room with CP/RP, office, conference room with air conditioning and false ceiling are provided with recessed mounted 2X36W fluorescent lamp with mirror optic reflector.

For LT room, DG, Store etc. where no false ceiling or AC provided, industrial type 2x36W fluorescent lamp is used.

For cable cellar bulk head or industrial type 2x36W fluorescent lamp is used as per specification.

Battery room is provided with corrosion proof industrial type 2X36W fluorescent lamp.

For DC emergency bulk head incandescent lamps are used.


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

115

-Substations

Interlocking &Protection Philosophy

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

116

-Substations

Fundamental Concepts CIRCUIT BREAKER

Normally kept interlock free European practice is to prevent opening or

closing of circuit breaker when isolator is in intermediate position

CB is operated only when isolator is fully open or close

Isolator Isolator is allowed to operate (open offload)

when associate Circuit breaker is open Earth switch is closed

Isolator permitted to operate for bus transfer when voltage on both the sides are same

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

117

-Substations

Fundamental Concepts EARTH SWITCH

Earth switch is allowed to operate when adjacent isolators are open

Earth switch is used to earth the trap charges Nowadays, customer ask for same short

circuit rating of main blade & earth blade

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

118

-Substations

Interlocking : Single Bus scheme

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

119

-Substations

Interlocking : Double Bus scheme

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

120

-Substations

Interlocking : Three Bus scheme

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

121

-Substations

Interlocking : One & Half Breaker Scheme

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

122

-Substations

Introduction to Protection General protection requirements

applicable to Transmission/distribution substations

Distribution plants/ MV switchgear

Brief on various type of protection Application guide

Protection Philosophy

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

123

-Substations

G M

Generation Transmission Distribution Load

Generation Transmission Distribution Consumption

Electric Power Systems


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

124

-Substations


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

125

-Substations

K

EC

Protect people and property around the power system

Protect equipment, lines etc.. in the power system

Separate the faulty part from the rest of the power system

The main task for Relay Protection

U I


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

126

-Substations

Requirements on Protection System Speed

Thermal damage

Electro dynamic forces

Sensitivity High resistance faults

Reliability Dependability

Security


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

127

-Substations

Factors influencing reliability Choice of the protection system Principle of measuring Environment The maintenance Flexibility under different service conditions and

extension of the network


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

128

-Substations

Single failure criteria Fault clearance must be executed even in case

of a single fault in the clearance chain In the fault clearance system no part of the

clearance should have lower reliability Back-up clearance function must be there

Remote back up

Local back up


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

129

-Substations

Primary and backup protection zones

Remote back-up with time selectivity is most common at Medium and low voltage functions


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

130

-Substations

Remote back-up protection with time gradingProtection Philosophy

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

131

-Substations

Redundant protection system Separate measuring cores Duplicate trip coils Separate dc distribution/ double battery system Physical separation of protection system Separate cable ways


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

132

-Substations

DC supply

The protection system that gives back up for other protection should not be fed from the same DC supply

For example if line and transformer protections are from same DC the backup function of the transformer will not be able to operate for a failure to clear the fault on the line by the primary protection


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

133

-Substations

Principle of breaker failure protectionProtection Philosophy

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

134

-Substations

Duplication of breaker fail protection Often 2 out of 2 connection of current and time

is used to obtain high security For numerical relays this is not necessary Duplication of breaker fail protection gives high

reliability but lower security. Considering probability of failures only one

breaker failure relay is used


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

135

-Substations

Disturbance Registration and Fault Signaling Alarm system

DC system for alarm independent of distribution

Supervision of alarm voltage

Disturbance recorder & Event logger Analysis of print out will help discover inoperative

relays , incorrect settings and badly chosen measuring principle


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

136

-Substations

General protection requirements applicable to

Transmission/distribution substations

Distribution plants/ MV switchgear


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

137

-Substations

General protection requirements applicable to

Transmission/distribution substationsThis depends on following

1. Voltage level

2. Type of feeders

3. Application specific criticality


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

139

-Substations

Protection Philosophy normally followed at EHV level EHV/HV : 800KV ,400KV,220KV,132KV

Common protection

Busbar protection:

It is mandatory to provide bus bar protection up to 220KV level. Depending on criticality of installation and philosophy of each industry, it is optional to provide bus bar protection at 132KV level

Generally Low impedance type up to 400KV and high impedance /low impedance type for 220KV and 132KV

Duplicate protection (without Check zone) for each of the main buses for 800KV and 400KV stations

For 220KV/132KV ,one protection for each bus.


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

140

-Substations

Common protection contd

Local breaker back up protection. This protection is primarily provided to isolate

the system in case the circuit breaker fails to operate.

This protection isolates all the feeders which can feed the fault.

Mandatory from 220KV substation and above.


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

141

-Substations


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

142

-Substations


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

143

-Substations

Feeder wise Protection EHV : 800kv ,400kv ,220KV

Line Protection Main-1,Main-2 protection connected to

separate CT cores Both protections should have different

make/operating principle. Normally up to 400 KV, distance

protection is provided. For 220KV,distance for main-1 protection

and either distance or directional earth fault for main -2 protection is provided


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

144

-Substations

Transformer Protection Main-1,Main-2 protection connected to

separate CT cores Differential protection is provided for main-1 Restricted e/f is provided as main-2 Over fluxing protection Gas detector relay ( Buchholz) Over current protection Pressure relay for tap changer Oil level monitor

General protection requirements contd

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

145

-Substations

Transformer Protection Contd Gas detector relay ( Buchholz) Over load protection

Thermal relays

Temperature monitoring relays

Ground fault protection Differential protection Inter turn faults


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

146

-Substations

Capacitor Bank faults Terminal shunt faults Capacitor unit failures Capacitor unit over voltages Capacitor rack arc-over


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

147

-Substations

Capacitor Bank Protection Contd Short -circuit protection (3I >>) Ground-fault protection (I ) Overload protection (3I/U >) Under current protection (I/U

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

148

-Substations

Conditions as per IEC 60871-1 Capacitors should be able to withstand 10%

over voltage The capacitors should tolerate 30% over

current ( r.m.s. value) arising from over voltage and harmonics. Depending on the capacitance deviations, which may be not more than 1.15 Cn, the maximum current may be up to 1.15 x 1.3 = 1.5 In

Capacitors may not be reconnected until they have discharged to 10% of their rated voltage.


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

149

-Substations

Unbalance relay detects :- Detects asymmetry due to

Blown internal fuses

Short circuits across bushings

Short circuits between capacitor units /racks

If capacitor value decrease below 5/6 of nominal value bank must be taken out of service

Faulty elements taken out by fuses cause increase in voltage level

Capacitors can withstand 110% of rated voltage


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

150

-Substations

Unbalance Protection Schemes :- Provide early unbalance alarm signal to

indicate the operation of fuses (internally or externally fused capacitors) or failure of capacitor elements (fuse less capacitors)

Trip the bank for unbalances that are large enough to indicate that continuing operation may result in damage to remaining good capacitors or elements from over voltage

Many schemes available for detecting unbalances Most installations will require an individual

engineering analysis to determine the most appropriate detection scheme


AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

151

-Substations

General SafetyCriteria

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

152

-Substations

General Safety Requirement Rule No. 34 Accessibility of Bare

conductors in buildings Ensure they are inaccessibile Provide necessary switches in accessible

position for rendering them dead whenever required.

Take safety measures as recommended necessary by inspector.

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

153

-Substations

General Safety Requirement Rule No. 35 Danger Notices

Applicable for Medium, high and extra-high voltage installations.

Insists on danger sign depicted by skull and bones as per IS:2551

To be installed on every Motor, generator, transformer & other electrical

plant and equipment together with apparatus used for controlling or regulating the same.

All supports of extra high voltage, O/H lines which can be easily climbed upon w/o aid of ladder of special appliance

If installation not possible, then Dangerword should be affixed as near as possible, voltage printed on equipment.

For enclosed equipment, it should be affixed to said enclosure

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

154

-Substations

General Safety Requirement Rule No. 36 Handling of electric supply-lines

and apparatus Before handling any conductor adequate

precaution to be taken to see that conductor is de-energized.

Accidental induction from adjacent live conductors to impose no danger to work person.

Before working on any live electric supply-line or apparatus, proper authorization from Inspector to be taken.

Every telecommunication line on high voltage supports are deemed to be considered as high voltage lines.

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

155

-Substations

General Safety Requirement Rule No. 41 Distinction of different circuits

Different circuits shall be distinguished by means of permanent nature.

Applicable for every generating station, sub-station, junction box or pillar in which there are any circuits or apparatus (whether intended for opeartion at different / same voltage.

Rule No. 41-A Distinction of the installations having more than one feed Applicable for every installation including

substation, double-pole structure, four pole structure of any other structure having more than one feed.

Indication should be of permanent nature.

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

156

-Substations

General Safety Requirement Rule No. 64 (2- e) Provision of Baffle Walls

A substation or switchstation with apparatus having more than 2000 liters of oil whether indoor / outdoor Baffle walls of 4 hours fire rating shall be

provided Between Single phase banks On the consumer premises Where adequate clearances between units

are not met.

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

157

-Substations

General Safety Requirement Rule No. 64 (2- e) Provision of Soak Pit

Oil soak pit to be provided > 9000 litres of oil Suitable Oil tank, chamber, receptacle to be

provided. Special precaution to be taken to prevent

ignition of oil from any cause & provision shall be made for extinguishing any fire that may occur.

Spare oil shall not be stored in any such sub station or switch station.

Dry type transformers to be provided for basement & residential areas

All transformers & switchgear to be maintained as per manufacturers instructions proper record to be maintained

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

158

-Substations

General Safety Requirement Rule No. 64 (3) Over voltage Protection

All EHV apparatus shall be protected against switching and lightning overvoltages

Proper insulation co-ordination should be ensured to protect and maintain the stability of interconnected units of the power system

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

159

-Substations

General Safety Requirement Rule No. 64 A Additional Provision

Interlocks Isolator should not be operated until adjacent

CBs are in open condition. Earth switches should not be closed until

Isolators are in Open condition When two supplies are not intended to be

operated in parallel, CBs shall be interlocked to prevent inadvertent paralleling

When parallel operation of transformer takes place, primary CB will trip incase of tripping of secondary CB

All gates & doors to be interlocked to avoid any person coming in proximity of live parts

Neutral switching to be adopted for two or more generators operating in parallel

AB

B P

ower

Tec

hnol

ogie

sBA

PTP

S -

160

-Substations

General Safety Requirement Rule No. 64 A Additional Provision

Protection Over-current, Earth fault & Earth leakage

protection to be provided where ever required Gas Pressure type, winding & Oil temperature

protection to give alarm & tripping for all transformers 1000kVA & above

Differential protection to be provided for 10MVA & above.

All generators 1MVA & above shall be protected by REF, protection should also be given for earth fault & leakage

Busbar protection with LBB MUST for all substations with voltage of 220kV & above

A global leaderin power and automation technologies

that enable utility and industry customersto improve their performance

while lowering environmental impact

Substation EngineeringContentSlide 3IntroductionIntroduction : The Electric UtilityIntroduction : Power Evacuation substationIntroduction : Transmission substationIntroduction : Distribution substationSlide 9Switching ConfigurationSwitching Configuration : Single Bus SchemeSlide 12Switching Configuration: Single Bus SchemeSlide 14Switching Configuration : Bus SectionalizerSlide 16Switching Configuration: Double Bus SchemeSwitching Configuration : One Main & TransferSlide 19Slide 20Switching Configuration : Main & Main cum transferSlide 22Slide 23Switching Configuration : Double MainSlide 25Switching Configuration : Double Main with bypassSlide 27Switching Configuration:Application of Transfer BusSlide 29Switching Configuration: Three Bus SchemeSlide 31Switching Configuration : Three BusSlide 33Switching Configuration : Three Bus (Bus Coupler)Switching Configuration : Three Bus (Bus Transfer)Slide 36Switching Configuration: One & Half CB SchemeSlide 38Various Busbar Configuration : One & Half CB SchemeSlide 40Switching Configuration : ApplicationSlide 42Slide 43Engineering CalculationsSlide 45Slide 46Engineering Calculations : EDFInputs for CalculationSlide 49Engineering Calculations : EarthingEngineering Calculations : DSLPSlide 52Slide 53Slide 54Engineering Calculations : Sag TensionSlide 56Engineering Calculations : Wind PressureEngineering Calculations : Temperature RiseSlide 59Slide 60Slide 61Slide 62Layout EngineeringLayout Engineering : Plan ViewSlide 66Slide 67Slide 68Slide 69Slide 70Slide 71Equipment & AccessoriesSlide 73Slide 74Slide 75Slide 76Slide 78Slide 79Slide 80Slide 81Slide 82Slide 83Slide 84Component & AccessoriesSlide 86Slide 87Slide 88Slide 89Slide 90Slide 91Equipment & Accessories : LT AC DistributionEquipment & Accessories : AC & DC BoardEquipment & Accessories : DC SystemSlide 95Slide 96Slide 97Slide 98Slide 99Slide 100Slide 101Slide 102Equipment & Accessories : P & I DiagramEquipment & Accessories : Fire Fighting BuildingSlide 105Equipment & Accessories : Hydrant SystemEquipment & Accessories : HVWS SystemSlide 108Equipment & Accessories : N2 InjectionEquipment & Accessories: Air Conditioning SystemEquipment & Accessories : Illumination SystemSlide 112Slide 113Slide 114Slide 115Fundamental ConceptsSlide 117Interlocking : Single Bus schemeInterlocking : Double Bus schemeInterlocking : Three Bus schemeInterlocking : One & Half Breaker SchemeProtection PhilosophySlide 123Slide 124Slide 125Requirements on Protection SystemFactors influencing reliabilitySingle failure criteriaSlide 129Slide 130Redundant protection systemDC supplySlide 133Duplication of breaker fail protectionDisturbance Registration and Fault SignalingSlide 136Slide 137Slide 139Slide 140Slide 141Slide 142Slide 143General protection requirements contdSlide 145Slide 146Slide 147Slide 148Slide 149Slide 150Slide 151General Safety RequirementSlide 153Slide 154Slide 155Slide 156Slide 157Slide 158Slide 159Slide 160Slide 161

Documents

Module PS5 Rev 1