Transcript MVAR MANAGEMENT

Reactive Power Management
- Case study
-- Nandan Pathak (AE)
ICT -2
ICT -1
200 MW
160 MVAR
200 MW
160 MVAR
G-3
G-4
160 MW
135 MVAR
G-5
160 MW
135 MVAR
220 kV Parli
Bus
220 kV
Girwali Bus
LOAD
160 MW
140 MVAR
LOAD
GENERATION
~
LOAD:
870 MW
730 MVAR
A ) GENERATORS:
a) High MVAR drawl
b) High excitation current
B) ICT:
a) Overloading due to MVAR
b) Low voltage on 220 kV bus ( 200 kV)
C) LOAD:
11 kV side:
a) Overload tripping
b) Very low voltages
c) Conductor snapping
d) Local load shedding
440 V side:
a) Failure of transformers
b) Conductor snapping
A) High seasonal load especially agriculture
during October to March
B) Failure of reactive compensation
A) Identification of areas
a) Beed district
b) Solapur district
c) Nanded district
d) Pabhani district
e) Latur district
A) Identification of radial feeders
~
220 kV
Girwali Bus
220 kV Nanded
160 MW 100 MVAR
~
220 kV Parbhani
100 MW 80 MVAR
132 kV Parli
Bus
132kV Beed
80 MW 60 MVAR
132 kV
Girwali Bus
132 kV Latur -1
90 MW 75 MVAR
132 kV Latur -2
60 MW 45 MVAR
On similar lines loaded 11 & 33 feeders were identified.
I) Reactive power compensation available :
i. Substation ----- 164 MVAR
ii. Switched capacitors on 11kV – 240 MVAR (0.6 X405)
II) Focus Area – 11 kV , 0.6 MVAR capacitors
a. Repairs in a central laboratory
b. On site replacement, checking, modification, training
Modifications adopted for
optimum compensation



1. Cell rating 0.66 Mvar at 12 kV
2. De-rating at Low Voltage
3. Modification
 A. Fixed capacitors
 B. Addition to basic scheme


4. On site demonstrations
5. Team visit – Nasik , Pune (R ),
Kolhapur, Sangli,Parbhani




1. Reduction in overload tripping of 11 kV &
33 kV feeders.
2. Reduction in blowing of HG fuses at 33/11
kV transformers.
3. Reduction in conductor snapping.
4. Improvement in voltage profiles
LT
105 Volts to 190 volts
 11kV 7.6 kV to 9.8 kV

ICT -2
ICT -1
250 MW (200)
100 MVAR(160)
250 MW(200)
100MVAR(160)
G-3
G-4
G-5
200 MW(160) 200 MW
60 MVAR(135) 60 MVAR
195 MW(150)
80 MVAR(140)
220 kV Parli
Bus
220 kV
Girwali Bus
LOAD
LOAD
GENERATION
~
Voltage changes:
220 kV
132 kV
33 kV
LOAD:
1095 MW (870)
400 MVAR (730)
215 kV (200 kV)
125 kV (106 kV)
31 kV (27 kV)
Radial load changes
~
132 kV
Girwali
Bus
132 kV Latur –2
132 kV Latur –1
105 MW 40 MVAR 70 MW 30 MVAR
(90 MW 75 MVAR) (60 MW 45 MVAR)
~
132 kV
Parli Bus
132kV Beed
95 MW 30 MVAR
(80 MW 60 MVAR)
KWH recorded on 11kV Matkuli feeder from 132 / 11 kV T/F at 132 kV Ashti substation
MONTH
January
February
March
April
May
June
July
August
September
October
November
December
KWH 1998
791500
545000
667900
539400
512000
164400*
313900
310400
330600
500300
530400
307300*
KWH 1999
1101100
938100
819800
790900
473200
459800
1170300
948000
630400
706100
854700
1104100
KWH 2000
1014800
699100
663300*
87400*
-*
167700*
442100
490900
342700
350100
626000
542000
KWH 2001
401700
239400
262200
183400
275400
43800**
•---Load shifted to another feeder --- Load of other feeder taken on this feeder
•** --- kWh meter stopped due to leading PF
Note:
0.6 MVAR capacitor bank recommissioned at village Pandharee on Dt.28.11.2000
0.6 MVAR capacitor bank added at same location on Dt.4.12.2000
New 0.6 MVAR capacitor bank commissioned at Pokharni Phata on Dt.8.12.2000
Ju
Se
us
t
pt
em
be
r
Oc
to
be
No
r
ve
m
be
De
r
ce
m
be
r
ly
Ap
ril
M
ay
Ju
ne
M
ar
ch
ry
ar
y
br
ua
nu
Au
g
Fe
Ja
1200000
1000000
800000
1998
600000
1999
2000
400000
2001
200000
0
Energy savings on 11 kV Matkuli feeder
Month
Forecasted Energy sent
out (kWH)
Actual Energy sent out
(kWH)
Savings
(kWH)
Remark
Dec 2000
689997
542000
147997
21.45 
Jan 2001
624172
401700
222472
35.60 
Feb 2001
520905
239400
281505
54.00 
Mar 2001
562029
265200
296829
52.00 
Apr 2001
511766
183400
328366
64.10 
May 2001
451451
275400
176051
39.00 
Total
3360320
1907100
1453220
43.24 
1.System requires high order reactive compensation.
2.Use of fixed value non switched/seasonal manual switched
capacitors is economical.
3. Complementary switching for optimum compensation.
4. Dedicated setup for overall line loss reduction.