ISTS

ISGS -II

SEB-B drawalMain = (T+U+X)

Standby = (V+W+Y)

SEB-A drawalMain = (G+H+N+O+Y)Standby = (L+M+Q+R+X)

Metering Philosophy under ABT regime

Other than NTPC Station

ISGS-I injectionMain = (F+G+H+J+K)Check=(F'+L+M+J'+K')Standby = (A+B+C+D+E)

NTPC Station

SEB-B

ISGS-II injectionMain = (M1+M2)Check=(C1+C2)Standby = (S1+S2)

ISGS -I

Aux. Aux.

ISTS

ISTS

SEB-A

SEB-A

A B D EC

FF'

G HJJ'

KK'

L M

SEB-A

ST U

VW

X

Y

SEB-B

N O P

Q R

C1 C2

M1 M2

S1 S2

Aux.

Main Meter

Standby Meter

Check Meter

Points for Energy AccountingInjection by NTPC Generating Stations :

Main &check meters on Outgoing feeders Standby meters on HV side of GT/TT

Injection by other Generating Stations :

Main &check meters on HV side of GT/TT Standby meters on Outgoing feeders

Drawl by SEBs

Main -HV side of ICTs at GS and CTU S/S, Receiving end of Lines directly connected to ISGS

Respective ends of Lines connected to other SEBs Standby – LV/ Tertiary side of ICTs

Other end of lines connected to other SEBs

Special Energy Meter FeaturesSpecial Energy Meter Features

• STATIC TYPE

• COMPOSITE METER

• HIGHEST ACCURACY IN POWER INDUSTRY

• 3 PHASE-4 WIRE CONNECTIONS / MEASUREMENT

• DIRECT MEASUREMENT AS PER CT/PT SECONDARY QUANTITIES

- 110V PH TO PH/63.51 V PH-N

- 1 AMP OR 5 AMP

- VA BURDEN NOT >10 ON ANY OF THE PHASES

• WORKS ON REAL TIME CLOCK

• NO CALIBRATION REQUIRED

• TIME ADJUSTMENT FACILITY

• HIGH SECURITY OF DATA STORAGE

Raw dataWEEK FROM 0000 HRS OF 06-01-01 TO 0837 HRS OF 15-01-01NP-0185-A 91858.5 99968.5 39195.5 06-01-01 00 51 +21.57 48 +21.68 50 +21.71 49 +21.33 …. 04 19 +20.61 23 +20.80 19 +21.05 00 +21.35 … 08 00 +24.95 00 +24.95 00 +25.09 00 +24.38 … 12 71 +24.38 52 +23.98 30 +23.81 13 +24.03 …16 00 +23.37 00 +23.52 00 +22.87 00 +21.66 … 20 00 +25.75 00 +25.32 00 +25.40 00 +25.37 … NP-0185-A 94117.2 99968.5 40313.5 07-01-01 00 59 +20.94 54 +21.01 59 +20.79 58 +21.05 … 04 33 +20.05 38 +20.17 37 +20.49 28 +20.90 …08 00 +22.99 06 +23.10 00 +22.81 00 +22.94 … 12 85 +20.93 51 +20.65 21 +20.79 00 +19.89 … 16 07 +20.14 01 +20.53 00 +20.72 00 +20.66 …20 05 +23.62 08 +23.23 16 +23.25 27 +23.40 … NP-0185-A 96172.2 99968.5 41236.9 08-01-01 

Special Energy Meter Various ChecksSpecial Energy Meter Various Checks

CHECKS for DATA VALIDATION :

• NOMINAL VOLTAGE CHECK• FREQUENCY• TIME CORRECTION• WATTHOUR CHECK• PREVIOUS WEEK DATA• ALGEBRAIC SUM

• RAW DATA IN WHr

• MWhr = RAW DATA x CT RATIO x PT RATIO

• PAIR CHECK DONE FOR MAIN/ CHECK/ STANDBY/ FICTMETERS ( ex. : for both sides of ICTs, Lines, GT side & Line side at ISGS.

Special Energy Meter Data ComputingSpecial Energy Meter Data Computing

Reactive Energy Accounting

Reactive Energy is measured

when system voltage is

> 103% of Nominal Voltage< 97% of Nominal Voltage

Loss computations

15 min block-wise % loss =

(Sum of all Injections from ISGS + net IR imports)

X 100

(Sum of all Injections from ISGS + net IR imports) -

(Sum of Drawals by all beneficiaries from Central Grid)

Use of Notional Loss in scheduling

• % Average loss (15 min. blockwise) aggregated over the last week will be used in Scheduling Process for the next week.

(for arriving at the ex-periphery Drawal Schedules of Beneficiaries)

%loss Graph Loss Table

0.5% REDUCTION MEANS MORE THAN 100 CR ANNUAL SAVINGS0.5% REDUCTION MEANS MORE THAN 100 CR ANNUAL SAVINGS

Loss for the week Loss % Week applied for

From To   From To

16-Sep-02 22-Sep-02 4.83 30-Sep-02 6-Oct-02

6-Jan-03 12-Jan-03 3.9 20-Jan-03 26-Jan-03

20-Oct-03 26-Oct-03 3.38 3-Nov-03 9-Nov-03

19-Jan-04 25-Jan-04 3.92 2-Feb-04 8-Feb-04

24-May-04 30-May-04 2.55 7-Jun-04 13-Jun-04

9-Aug-04 15-Aug-04 2.54 23-Aug-04 29-Aug-04

17-Jan-05 23-Jan-05 3.25 31-Jan-05 6-Feb-05

7-Feb-05 13-Feb-05 3.04 21-Feb-05 27-Feb-05

30-May-05 5-Jun-05 2.95 13-Jun-05 19-Jun-05

27-Jun-05 3-Jul-05 3.49 11-Jul-05 17-Jul-05

11-Jul-05 17-Jul-05 3.73 25-Jul-05 31-Jul-05

25-Jul-05 31-Jul-05 3.53 8-Aug-05 14-Aug-05

1-Aug-05 7-Aug-05 3.3 15-Aug-05 21-Aug-05

8-Aug-05 14-Aug-05 2.92 22-Aug-05 28-Aug-05

TYPICAL %AVERAGE LOSS FIGURES FOR CENTRAL GRID IN SR

%Average losses In other Regions :

NR 3.5 to 4.5

ER 3.0 to 3.5

WR 5.0 to 6.0

BACK

OTHER REGIONS

%loss for different weeks from 2003- 2005

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51

Week No.

%lo

ss

2003-042004-05

2005-06

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