PCM’s Mailing List
1) Chief Engineer (LD), MSETCL, Kalwa. Fax-27601769/65
2) Chief Engr. (Trans O&M), MSETCL, Bandra. Fax No. 022 - 26590808/26598587.
3) CE (W), MSEGCL, 3rd floor, Prakash gad, Mumbai.
4) S.E. (T&C), MSETCL, Aurangabad Fax-0240-2234220 /2346290
5) S.E (T&C), MSETCL, Pune. Fax-9520-2617532/2612342
6) Dy. CE (T&C), MSETCL, Koradi, Nagpur. Fax- 07109 - 262162
7) S.E.(T&C), MSETCL, Vashi Fax- 022-27656039
8) S.E.(Testing), Bhusawal, Dist: Jalgaon Fax-02582-250379
9) S.E. (Task Force), MSPGCL, Nagpur Fax- 0712-2591717.
10) S.E.(TCC), MSETCL, Karad. Fax.No. 02164 255118
11) Chief Engineer (Gen), GSECL, H.O. Baroda. Fax-0265-5512129/2344537
12) S.E. (Testing), GETCO, Baroda. Fax-0265-2351218
13) Chief Engineer (LD), MPPTCL, Jabalpur, Fax - 0761- 2664343 / 2970119.
14) E.D. (T&C), MPPTCL, Jabalpur. Fax-0761-2702710
15) ED (Engg.) MPPGCL, Jabalpur Fax- 0761-2660063
16) Chief Engineer (LD), CSPTCL, Raipur. Fax-0771 - 2574174
17) C.E. (T&C), CSPTCL, Raipur.Fax-0771-2574749
18) EE (T), CSPGCL- Fax.No. 07789-226227
19) S.E. (T&C), CSPTCL, Bhilai. Fax.No. 0788 - 2281561
20) S.E. (T&C), CSPTCL, Raipur. Fax No.0771 - 2574749.
21) EE, Division VIII (MRT), Elect. Dept; Goa Fax 0832-2735124.
22) SE, Electricity Dept., DNH, Silvasa. Fax : 0260-2642338
23) Executive Engr., Electricity Dept. DD. Fax: 0260-2250889
24) D.G.M. (O.S. ),N.T.P.C., Mumbai, Fax- 28216692
25) DGM, NTPC WR – II, Raipur, Fax: 0771 - 2544550
26) D.G.M. (EM), KSTPS, NTPC, Korba Fax 07759-233088 (Tele fax: 232440)
27) DGM (EMD), VSTPS, NTPC, Vindhyachal Fax-07805-247713
28) DGM (EM-I), NTPC, SIPAT Fax-07752-246506 (Tele fax: 246691)
29) AGM (O&M), KGPP, Adityanagar, Surat Fax 0261-2861428/2861433
30) Sr.Supdt. (EM), Gandhar, NTPC Fax-02642-87402 / 87450
31) DGM (O.S.), WRLDC, Mumbai Fax-28235434
32) DGM, WRTS-I, POWERGRID, Nagpur, Fax- 0712- 2631051 / 641366
33) AGM, WRTS-II, POWERGRID, Baroda Fax-0265-2480952 (Tele fax: 2487542)
34) SME (E), TAPS-3&4,Tarapur Fax 02525-282001/282073
35) Maintenance Superintendant, TAPS –1 & 2, Tarapur.Fax- 02525-282121
36) SME(E), NPCIL , Kakrapara Fax 02626-234266
37) GM (Maint.). TORRENT Power., Ahmedabad.Fax-079-27506679
38) AGM (QAIT), TPC, Trombay. Fax –022-66687088
39) Asst. VP, Dahanu TPS Fax- 952528-222576 / 222039
40) GM (O & M), Reliance Infrastructure Limited, Mumbai Fax-30094488
41) GM (Electrical), JPL, Raigarh, Fax. No. 7767-281995, 281993.
42) AGM (OS), NSPCL, New Delhi . Fax.No.011 26717381/26717363/26717366
43) Vice President, APL, Ahmedabad 079-25557176
44) GM, RGPPL, Anjanwel, Guhagar, Ratnagiri, Fax.No. 02359 241071
45) GM, JSW Energy Ltd., Jindal Mansion, Mumbai- Fax.No.022 23526400
46) GM, CGPL, Mundra Fax.No. 02838 661188
47) Director (G M Division), CEA, New Delhi. Fax.No.011-26109750
Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014
1.0
Introduction: Two separate events occurred at about 1910 and 1921 hrs on 12.03.2014 at
400 kV Chorania s/s. During the latter event there was tripping of all the CGPL running units. The
grid also experienced a large drop in frequency. Special meetings were held on 19.03.2014 and
21.03.2014 at WRLDC, Mumbai and CGPL Mundra respectively to discuss and analyze the
occurrence of 12.03.2014 in the GETCO/CGPL system. Based on the discussion and data submitted
for analysis, the following report is prepared.
The list of participants is enclosed at Annexure-I.
2.0
Antecedent Conditions
The antecedent conditions at about 1900 hrs of 12.03.2014 were as below:
System Frequency:
49.95 Hz
ALL INDIA PARTICULARS
Region
WESTERN REGION PARTICULARS
Demand met (MW) State
Demand met (MW)
NR
32,453 Maharastra
15,129
WR
36,033 Gujarat
10,551
SR
35,103 Madhya Pradesh
6,213
ER
15,537 Chattishgarh
2,854
NER
1,874 Dadra & Nagar Haveli
ALL INDIA
625
1,21,005 Daman & Diu
244
Goa
340
Following transmission lines in the vicinity were under forced outage in the antecedent conditions

400 kV Bachau –Ranchodpura (Vadavi)-II since 13:38 hrs of 12.03.2014.

220 KV Bachau-Halvad D/C since 22:50 hrs of 16.02.2014 (due to tower collapse)
The injection at CGPL was around 3750 MW and the loading of transmission lines from CGPL
Mundra was as follows:

400 kV Mundra – Bachhau D/C

400 kV Mundra – Chorania (Limbdi) D/C : 1510 MW (755 MW /ckt)

400 kV Mundra- Jetpur D/C
: 1110 MW (555 MW /ckt)
: 1144 MW (572 MW/ckt)
400 kV Kosamba-Chorania-1 line was under construction and kept in charged from Chorania end.
Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 1
3.0 EVENT DESCRIPTION
3.1 : Event-1 at 19:10:43:273 hrs on 12.03.2014 at 400 kV Chorania s/s:
Following two tripping took place at 400 kV Chorania s/s:
(i) At 19:10:43:273 hrs of 12.03.2014, 400 kV Chorania-Kosamba-1 at Chorania end
(ii) 400 kV CGPL-Chorania-I tripped at both ends.
It was reported that B-ph bushing of the Line reactor of 400 kV Chorania-Kosamba-1 at Chorania
end failed and caught fire. The fire was extinguished by the fire tender already parked in the
substation. Line tripped on reactor differential and distance protection.
It was also reported that the NGR LA of the Line reactor of 400 kV CGPL-Chorania-1 at Chorania
end failed resulting in tripping of 400 kV CGPL-Chorania-I on operation of Reactor REF protection.
There was a direct trip command sent to remote end. However reasons for failure of the NGR LA of
this line only, was not clear as other lines have also seen the same stress and LA did not fail.
Impact of Event 1: Consequent to the loss of 400 kV CGPL-Chorania-1, the power flow on 2nd
circuit of CGPL Mundra-Chorania increased from 752 MW to 980 MW. The power flow on 400 kV
CGPL-Jetpur D/C lines increased from 572 to 704 MW each circuit, while the power flow on CGPLBachau D/C lines increased from 561 MW to 692 MW on each circuit. Considering the high loading
on the 2nd ckt from CGPL to Chorania and depletion of the network, generation reduction at CGPL
Mundra was considered necessary by operators at WRLDC, SLDC-Gujarat, NLDC and CGPL
Mundra.
WRLDC in consultation with SLDC-Gujarat and CGPL Mundra was exploring the possibility of
restoring the 400 kV CGPL-Chorania-1 without Line reactor at Chorania end. Meanwhile another
event took place at the same substation, and is as given below.
3.2 : Event-2 at 19:21 hrs at 400 kV Chorania s/s:
LBB Operation of Bus-2: While the above actions were being taken up, the following lines
connected to Bus 2 of 400 kV Chornia tripped at 19:21:57.273 Hrs on operation of LBB
protection of bus-2 at Chorania having Double Main and Transfer Switching Scheme. Following
lines tripped due to operation of LBB.
a. 400 kV Chorania-Asoj
b. 400 kV Chorania-Ranchodpura (Vadavi)-2
Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 2
c. 400 kV Chorania-CGPL-2
d. 400/220 kV ICT-2 at Chorania
e. 400 kV Chorania-Amreli S/C
The analysis of the protections and operation of LBB is discussed in detail in Annex-2. The
outcome of the analysis for operation of LBB and trippings on power swing is as follows:
During the fire on the “B” phase of the line reactor of this line, it is suspected that the fire might
have spread to control cables and the CT wiring of Main-I or the Bushing CT wires of the reactor
and A.C. Auxiliary supply cables might have got damaged. Due to this the A.C supply might
have leaked into the CT cables of either Main-II DPS or the reactor bushing CTs (used for line
current compensation) and this leakage current of magnitude more than 200mA was extended to
the Main-II DPS relay. The master trip relay after the earlier tripping of the line breaker was not
resetted. This resulted in satisfying the conditions for stuck breaker condition and operation of
LBB relay of this line.
Tripping on Power Swing: Subsequently the following additional lines tripped at 19:21:58.150
hrs in Zone-1, on Power Swing
a. 400 kV Bachau-CGPL-1 at Bhachau end in Z-1.
b. 400 kV Bachau-CGPL-2 at Bhachau end in Z-1.
c. 400 kV Jetpur-CGPL-1 at Jetpur end in Z-1.
d. 400 kV Jetpur-CGPL-2 at Jetpur end in Z-1.
e. 400 kV Bachau-Ranchodpura-1 tripped at Bhachau end in Z-1.
f. 220kV Bhachau-Lalpar & Bhachau-Morbi lines at Bhachau end in Z-1.
WRLDC have observed that angular separation between CGPL bus with respect to Bhadrawati
was seen to sharply increase from 17° (during steady state) to 180° followed by loss of
synchronism.
However the subtle points to note on the above observation and the Zone-1 power swing seen by
the Distance Protection Scheme (DPS) relays on lines at the adjacent buses connected to CGPL,
are as follows:
(i)
A DPS relay would sense Zone-1 fault during a power swing only if the electrical centre
of the two buses connected through a line moves into the line section. This is only
possible if the angular separation between these two adjacent buses connected through the
line moves towards 180°.
Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 3
(ii)
Since the lines emanating from CGPL have tripped in Zone-1 power swing it implies that
the angular separation between the CGPL bus and the adjacent buses was approaching
180° and due to this the electrical centre between these buses and CGPL was moving
within these line sections. Hence the lines tripped on Z-1 power swing in about 1 second
after event 2.
(iii)
The observation of angular difference between CGPL and Bhadravati at the point when
these lines tripped in Z-1 power swing is estimated to around 72° after one second (the
oscillations of the order of 0.2hz was observed between the CGPL & Bhadravati PMU
plot) and would reach to 180° after about 2.5 seconds. However this angular separation
between far way buses is of no signification in the transient analysis.
3.3 : This led to non availability of evacuation from CGPL leading all units at CGPL to run on
house load, except Unit#40 which tripped on SPS operation. After 5-6 mins of operation of
Unit#10, Unit#20, Unit#30 & Unit#50 on house load, all these units were hand tripped,
except Unit#10 which tripped on HP exhaust hood temp very high. The frequency of the
islanded system of CGPL Mundra touched to 52.885 Hz (at 19:21:59:200) and the governor
action immediately controlled the frequency. The house load operation could continue only
for about six minutes after which there was a blackout at CGPL.
With this CGPL was completely out of the grid and collapsed.
3.4 : Impact of event-2 and Actions taken by WRLDC/SLDC:
The frequency in the grid rapidly declined and touched 49.285 Hz within 3 minutes due to
sudden deficit of 4050 MW. Following actions were immediately by WRLDC taken for system
security:
a. Koyna
hydro,
SSP
hydro
and
thermal
stations
of
NTPC
(Kawas/Gandhar/Korba/Vindhyachal/Sipat), DGEN (infirm injection) were directed
to maximize generation at all the units on bar. One additional units of SSP hydro was
also synchronized.
b. Power order on HVDC Mundra Mahendragarh Bipole was reduced from 2000 MW to
1500 MW to control the critical loading on 400 kV SSP-Kasor, SSP-Asoj and IndoreAsoj.
Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 4
c. Power flow on HVDC Chandrapur-Padghe Bipole reduced from 900 MW to 600 MW
to control critical loading on 400 kV Boisar-Vapi line
The frequency was brought above 49.8 Hz within 10 minutes of the incident and it was
brought within the IEGC band in the next 25 minutes.
3.5 : Restoration of CGPL:
Power supply to CGPL Mundra was extended from 400 kV Jetpur line at 19:37 hrs
3.6 : Load Relief during Event-2:
The reported load shedding due to operation of d/dt relay as reported by the respective
utilities is as under:
4.0 : SUMMARY AND RECOMMENDATIONS :
The analysis of the occurrence has revealed several issues that need to be addressed for preventing
reoccurrence of such events and for enhancing system security. The summary along with
recommendations is as under:
i)
Failure of reactor of 400kV Chorania-Kosamba line: Failure of “B” phase reactor
of 400kV Chorania-Kosamba line No. 1 to be taken up with the manufacturer by
GETCO and the report of the OEM to be shared in the next PCM of WRPC.
ii)
Failure of NGR LA of 400kV CGPL-Chorania line 1 : Regarding the matter of
failure of NGR LA of CGL make, POWERGRID shall take up the same with OEM
and share the report in the PCM.
Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 5
iii)
Operation of LBB of 400kV Chorania-Kosamba line No. 1: It is recommended that
during fire, all the control wiring fuses of the control panel of the affected
element/bay should be removed immediately so as to avoid leakages in damaged
cable cores. The immediate resetting of the tripped relays is not possible under such
circumstances, since the S/S officials are generally busy controlling the fire.
iv)
Load Relief Related: It was observed that the rate of fall of frequency at different
locations in the grid depends on the stiffness of the point w.r.t. to the point of
disturbance in the grid (where generation loss had occurred). Therefore the rate of fall
of frequency in MP, Chattisgarh which are electrically far away from Mundra would
be lesser than in Gujarat or Maharashtra. It was therefore recommended that since
UMPPs and large generating stations are located in Gujarat and Chattisgarh States
more quantum of load shedding should be wired up through df/dt relays in Gujarat
and Chattisgarh State. Further the rate of df/dt in Gujarat system for the first stage is
set at 0.2Hz/sec, therefore Gujarat should explore to set the first stage at 0.1Hz/sec.
These may be discussed in the next PCM.
v)
Governor response of generators in NEW Grid :
The loss of 4000 MW at 19:22 hrs during the evening peak hours led to drop in
frequency of 0.67 Hz. Considering the load loss of 1100 MW, the system inertia
comes out to be around 4300 MW/Hz without considering the frequency dependence
of load and governor response. Thus the automatic response through FGMO/RGMO
from rest of the generators on bar in the grid was inadequate.
It was recommended that all generating units mandated for RGMO/FGMO in Western
Region should furnish plots of Active power vs frequency available/recorded during
the period 1920 to 1930 hrs of 12.03.2014 at the generating stations to WRLDC and
WRPC by 22.04.2014. Necessary co-ordination may be done by WRLDC for getting
the above data and a white paper on the same shall be published by WRLDC. Also
Utilities shall submit complete details of governor setting of the generating units
mandated for RGMO/FGMO to WRLDC.
WRLDC shall compile this data for
ascertaining the frequency response of the generators during either the frequency rise
or frequency fall cases.
vi)
Tripping of lines in Z-1 power swing: After the operation of LBB protection the
evacuation from CGPL got depleted and resulted in setting up of power swings in the
system. The lines connected to CGPL Mundra subsequently tripped in Z-1 due to the
power swing, before the generators at CGPL Mundra fell out of synchronism (even
Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 6
before the first pole slip) with the rest of the grid generators. As per the existing
protection philosophy power swings entering in Z-2 & Z-3 are blocked and power
swings entering in Z-1 of DPS are allowed to trip the line due to the severe nature of
power swings entering in the Zone-1. Therefore Z-1 philosophy adopted for tripping
the lines in Z-1, connected to the generating stations and lines nearby the vicinity of
generating stations which are supposed to power swings needs to be discussed in the
PCM. Under such circumstances the possibility of using out of step protection relay as
an alternative to tripping a line in Z-1 power swing requires to be deliberated in the
PCM. This incidentally has also been raised by the Hon’ble commission CERC in its
order on the grid disturbances of 30th & 31st July 2012.
vii)
Dynamic Compensation: There is a need to simulate the events and run transient
stability studies to see the anticipated governor response, df/dt enhancement and also
suggest measures to improve the dynamic stability. For this the event-2 data of the
grid requires to be collected, simulated and examined from transient stability point of
view. It is proposed that this may be studied by academic consultant like IIT-B. Also
it is desirable that WR Study Committee members avail academic training to be able
to conduct such special studies frequently. For the WR part, WRLDC shall collect the
governor response and submit white paper as mentioned above. However since the
entire grid is now synchronous, the governor response in other regions also desires to
be studied. For which WRLDC may take up with NLDC. Hence WRLDC may also
collect the snapshots of outside WR (by co-ordinating with NLDC) of the system
conditions. The incident data of PMUs and SCADA data, and other relevant data like
all India data along with governor response can then be taken up for simulation.
viii)
GPS Synchronization: The time stampings on the DRs generated during the above
occurrence did not coincide and there was quite a large time drift. GPS time
synchronization of the relays shall be carried out. The methodology/procedure for
carrying out the synchronization may be discussed in the next PCM.
ix)
Restoration of 400kV Bhachau (PG)-Ranchodpura line No.2: This being
important line, efforts should have been made to restore the same at the earliest. It
was informed by POWERGRID that permission was not given by WRLDC for test
charging the line after it tripped on transient fault. WRLDC informed that since the
line tripped on R-B (line to line) fault, therefore permission for second attempt of
charging the line was not granted. It was observed that the line rarely trips for
permanent nature of phase to phase involving R & B phases (R & B phase lines are
Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 7
physically located at the either side of the tower). While the concern of WRLDC was
noted, system operator should accept the fact that the declaration of healthiness of the
transmission element is the prerogative of the utility responsible for maintaining that
element. Hence priority should be given to charging the line, and not insist on getting
DR etc. DR and other analysis are post-facto in nature, if the past record/experience of
the utility is satisfactory. This would help earlier restoration of the element, since the
utility is the best judge of real conditions existing in the field.
x)
400kV Chorania-Kosamba line No. 1 line charging: The line was kept in charged
condition, without informing WRLDC resulting in confusion regarding failure of
reactor, as it took some time to ascertain that the line reactor of this line had failed.
Simultaneously, 400kV CGPL-Chorania line 1 also tripped on reactor REF resulting
in confusion as to which line reactor has caught fire. Charging any element which has
bearing on the regional system shall be informed to WRLDC before charging the
element.
xi)
PMU Wiring up at CGPL: The PMU data was not sufficient to analyze the
occurrence. Instead of wiring the current input of Unit#40 of the CGPL, line currents
of Bhachau lines would have been more useful.
xii)
Proposed Changes in SPS at CGPL Mundra :
Following changes at Sr.No.1 in the approved SPS table (enclosed at Annexure-III)
were recommended for immediate implementation, after due deliberations and were
agreeable to all the concerned.
As regards to revision in the existing SPS at CGPL, after detail deliberations,
following modifications in the existing SPS were suggested;
The existing SPS may be replaced by
Option-A :
i)
If line loading on any line exceeds 900MW back down generation at CGPL.
ii)
If line loading on any line exceeds 1200MW trip one unit at CGPL.
Option-B :
i)
For loss of any two lines trip one unit at CGPL.
ii)
For further loss of any two lines trip another unit at CGPL.
Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 8
CGPL representative requested that they are in agreement for modification of the
conditions in view of the threat to grid and also this would help survival of their units.
However, the scheme should be validated through studies and tripping of units
unnecessarily should be avoided, since tripping of large units not only impacts the
grid but also the units are stressed. Also the utilities responsible for maintaining the
transmission system for evacuation should maintain the transmission lines, so that
such that multiple tripping of lines do not occur. CGPL further proposed that
generation backing down would be carried out to the tune of 800MW, if any one line
out of the six outlet lines trips, further generation backing down of 800MW would be
carried out if second line tripes subsequently. WRLDC was of the view that backing
down is a slow process and under the circumstances quick actions are required and
therefore option-A & option-B are the most appropriate options to deal with the
situation. SLDC GETCO also expressed similar views.
It was therefore
recommended that CGPL would review the above options and send their comments at
the earliest for implementation of Option-A or Option-B as given above.
xiii)
Interim Scheme for immediate implementation:
PGCIL to extend signals of MW or tripping, preferably MW, to CGPL, so that the
existing scheme may be modified as per enclosed Annexure-3.
**************
Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 9
Annexure-I
Participants list for Special meeting (CGPL) held on19.03.14 at WRLDC, Mumbai
Sl.No.
Name
1 Shri S.D. Taksande
2 Shri Satyanarayan S.
3 Shri M.M. Dhakate
4 Shri P.D. Lone
5 Shri L.K.S. Rathore
6 Shri Shiva Suman
7 Shri B.B. Mehta
8 Shri J.N. Pancholi
9 Shri P. Mukhopadhyay
10 Shri V.K. Shrivastav
11 Shri Abhimanyu Gartia
12 Shri Anand Dubey
13 Smt. Pushpa S.
14 Shri Vivek Pandey
15 Shri Awani Rai
16 Shri Aditya P.Das
17 Shri N. Nallarasan
18 Shri R.M. Sankhe
19 Shri Vipul Raval
20 Shri K.N. Athavale
Designation
M.S.
S E (Comml.)
S.E.(Opn.)
E E (Comml.)
EE(Opn.)
A D (Comml.)
C. E.
O.S.D.
G.M.
AGM
D.G.M.
CM
CM
C.M.
Engineer
Dy. Mgr.
D.G.M.
G.M.
Group Head
Head Ele.
Organisation
WRPC
WRPC
WRPC
WRPC
WRPC
WRPC
SLDC, GETCO
GETCO
WRLDC
WRLDC
WRLDC
POWERGRID
WRLDC
WRLDC
WRLDC
WRLDC
NLDC
TATA POWER
CGPL
CGPL
E-mail
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
[email protected]
Mobile No.
9820878384
9223399938
8108787778
9867622823
9833371844
9869910968
9879200736
9978936145
9869438073
9869450221
9869088058
9428504065
9869404482
9869404673
9869414293
9869404569
8527077022
9099006541
7738373722
9227295358
List of participants for the Meeting held on 21 Mar 2014 at CGPL Mundra
Sr. No. 1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
Name
Shri K K Sharma Shri S K Negi Shri S Baijal Shri Pancholi Shri SA Patel
Shri P D Lone Shri Vivek Pandey Shri Anand Dubey
Shri Soni Shri K N Athavale Shri R M Sankhe
Shri K V Ghate Shri B M Shah
Shri Alok Uppal Shri Jagmit Siddhu Shri Naveen Yadav
Shri Sagnik Kundu Shri Sahoo Shri Avinash Kumar Shri Raman Bharmuria Shri Pryank Shah Designation
ED & CEO M D Head‐O&M OSD
EE EE Chief Manager Chief Manager
Manager
Head‐EMD Head‐Operations
Head‐IMD EE Group Head‐ EMD Group Head‐ EMD Group Head‐ EMD Shift Charge Engineer
Shift Charge Engineer
Shift Charge Engineer
Shift Charge Engineer
Commercial Controller Organisation
CGPL
G ETCO
CGPL
GETCO
G ETCO
WRPC
WRLDC
PGClL
PGClL
CGPL
CGPL
CGPL
GETCO
CGPL
CGPL
CGPL
CGPL
CGPL
CGPL
CGPL
CGPL
ANNEXURE-II
DETAILED ANALYSIS AND SEQUENCE OF EVENTS CO-RELATION
SEQUENCE OF EVENTS
Reports of the event along with DR/EL were forwarded by GETCO, POWERGRID and CGPL
Mundra to WRLDC and WRPC. The DR/EL was discussed in the meetings and detailed analysis of
the event was carried out based on the above reports and data from synchrophasors & SCADA and
was discussed in the meetings.
The Sequence of Events as inferred from the SOE in WRLDC SCADA and PMU data is as under:
t = -11 min 13 sec
400 kV Chorania-CGPL-1
t = -11 min 13.993s
400 kV Chorania-Kosamba-1
t = 0ms
400 kV Chorania-Asoj
t = 0ms
400 kV Chorania-Vadavi-2
t = 3ms
400 kV Chorania-CGPL-2 (both ends)
{19:10:43.276}
{19:21:57.273}
{19:21:57.276}
SPS-2 triggered for runback at CGPL units
t = 32ms
400/220 kV ICT-2 at Chorania
t = 80ms
400 kV Chorania-Amreli
t = 721ms
400 kV Bachau-CGPL-2 (from Bachau end)
t = 868ms
400 kV Bachau-CGPL-1 (from Bachau end) {19:21:58.141}
SPS-1 triggered for tripping of 1 unit at CGPL (unit#40 was pre-selected)
t = 1.315 sec
400 kV Jetpur-CGPL-1 (from Jetpur end)
t = 1.315 sec
400 kV Jetpur-CGPL-2 (from Jetpur end)
Loss of all Evacuating lines from CGPL. Station islanded and survived
t = 1.385 sec
400 kV Bachau-Ranchodpura-1
Loss of power supply at 400 kV bus of Bachau as 220 kV lines to Lalpar and
Morbi tripped while D/C to Halvad already under breakdown.
t= 1.397 sec:
400 kV CGPL Mundra-Bachau 1 on O/V (from CGPL end)
Annexure-II to the Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 1
t= 1.429 sec:
400 kV CGPL Mundra-Bachau-2 on Z1 distance (from CGPL end)
t= 1.431 sec:
400 kV CGPL Mundra-Jetpur-2 on O/V (from CGPL end)
t= 1.443 sec:
400 kV CGPL Mundra-Jetpur-1 on O/V (from CGPL end)
t= 2.733 sec:
Unit # 40 tripped (on SPS)
t= 2.787 sec:
Unit # 50 hand tripped
t= 14.107 sec: Unit # 20 hand tripped
t= 3 min, 46.430 sec: Unit # 30 hand tripped
t= 6 min, 42.273sec: Unit # 10 tripped on exhaust hood temperature high
CGPL power station Blackout
t = 15 minutes
Start up supply extended to 400 kV CGPL Mundra from 400 kV Jetpur
Analysis of DR / EL reports and operation of protection systems :
None of the DR/EL were seen to be time synchronized with GPS. However the inferences drawn
from the reports are as under:
a)
Event 1: 400kV Chorania-Kosamba line No.1 :
From Chorania end D.R it was observed that there was operation of reactor differential
protection and line distance protection for 400kV Chorania-Kosamba line at Chorania end
on failure of “B”phase reactor of the line. Both the protections sensed the fault correctly
and tripped the breaker at Chorania end and also direct trip command was sent to
Kosamba end.
b)
Event 1: 400kV Mundra-Chorania line-1 :
From Chorania end D.R it was observed that there was operation of REF protection of
reactor and fault current in neutral was 0.24 A. The operation of REF protection had
tripped the breaker at Chorania end and also sent direct trip command to Mundra end.
The operation of the REF protection at Chorania end on failure of NGR LA of the line
reactor is in order. Reason for failure of NGR LA is being studied by PGCIL.
c)
Event 2: 400kV Chorania-Vadavi line-2, 400kV Chorania-Amreli line, 400kV ChoraniaMundra-2 line :
Annexure-II to the Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 2
From D.R of Chorania end it was observed that the breakers of above lines tripped and
the triggering event was bus bar protection relay. However no fault in system was
observed through the disturbance record.
d)
400kV Chorania S/S Bus-II LBB operation : The Master trip relay of 400kV ChoraniaKosamba line No. 1, was not resetted during the tripping of the line due to “B” phase line
reactor failure. As per the DR of the event current of sufficient magnitude (>200mA) was
seen flowing in the “B” phase of the Main-II relay. Therefore for operation of LBB of this
line, both the conditions of stuck breaker protection i.e. Master trip operated and line
current more than 200mA got satisfied and the relay operated correctly. Following
elements connected to Bus-2 tripped 400/220kV, 500MVA ICT-2, 400kV Ranchodpura2, 400kV Asoj line No.2, 400kV, 50MVAR Bus reactor & 400kV Amreli.
During the fire on the “B” phase of the line reactor of this line, it is suspected that the fire
might have spread to control cables and the CT wiring of Main-I or the Bushing CT wires
of the reactor and A.C. Auxiliary supply cables might have got damaged. Due to this the
A.C supply might have leaked into the CT cables of either Main-II DPS or the reactor
bushing CTs (used for line current compensation) and this leakage current of magnitude
more than 200mA was extended to the Main-II DPS relay. The master trip relay after the
earlier tripping of the line breaker was not resetted. This resulted in satisfying the
conditions for stuck breaker condition and operation of LBB relay of this line.
e)
400kV Mundra-Jetpur line-1 & 2 :
From Jetpur end D.R it was observed that the lines tripped due to operation of DPS in Z1
and power swing detection from Jetpur end. The gradual fall of voltage and increase of
current seen by the relay suggests that the power swing has entered in Z-1.
f)
400kV Mundra-Bachau line-1&2 :
From Bachau end D.R it was observed that breakers tripped due to operation of DPS in
Z1 and power swing detection from Bachau end. The gradual fall of voltage and increase
of current seen by the relay suggests that the power swing has entered in Z-1.
g)
220kV Bhachau-Lalpar & Bhachau-Morbi lines:
Annexure-II to the Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 3
Both these 220kV lines tripped in Z1 and power swing detection from Bhachau end. The
gradual fall of voltage and increase of current seen by the relay suggests that the power
swing has entered in Z-1.
From the DRs of lines at e), f) & g), as above, it was observed that there was a gradual fall in voltage
from 1 pu to around 0.40-0.50 pu and a gradual increase in current, clearly indicating a severe power
swing between the CGPL generators and other generators in the grid. Further all these lines tripped
on entering of power swing in Z1 of the respective lines from opposite end of CGPL. Therefore
tripping of lines at e), f) & g), as above in Z-1 and power swing detection were in order.
The offline simulation studies carried out by WRLDC for the above event also suggests that the
power swing had entered in Z1 settings of DPS of the above lines.
The DRs and the ELs are enclosed at Annexure-IV.
Analysis of PMU data :
The PMU plots are enclosed at Annexure-V
a. The angular separation between CGPL bus with respect to Bhadrawati is seen to sharply
increase from 17 degrees to 180 degrees followed by loss of synchronism.
b. There was around 30 % voltage drop at CGPL Mundra within 1 sec 320 ms of loss of both
circuits of CGPL Mundra-Chorania followed by sudden rise in voltage. Reactive power of
CGPL generating units changed from -42 MVAR (lead) to 550 MVAR (lag) indicating fast
AVR action
c. Generation at CGPL Mundra is observed to reduce by around 100 MW after loss of both
circuits of 400 kV CGPL Mundra-Chorania D/C
d. The frequency of the 400 kV CGPL bus (islanded) touched 52.885 Hz after loss of
synchronism with the grid within 2 seconds. The second peak of frequency occurring after
7.400 seconds was within 50.5 Hz, possibly due to fast governor action.
Annexure-II to the Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 4
Annexure-III
SPS for CGPL
Bhachau-1
Bhachau-2
Or
Or
BhachauBhachauRanchodpura Ranchodpura Jetpur-1 & 2 line
CGPL Gen
1 or 2 Line Loading in MW
in MW
Chorania-1 Chorania-2 1 or 2 Line
Action at CGPL
1
>3100
X
X
>1500
2
>3100
X
X
>1500
3
>3100
4
5
6
7
X
>3100
>3100
>3100
>3100
X
X
X
X
X
>1500
X
>1500
X
>1500
>1500
>1200
X- indicates tripping of the line.
Trip mills this will reduce
generation by @500MW, except
for condition 2 where unit would
trip
Alarm for reduction in generation so
that the Jetpur lines loadings are
maintained around 1200MW
Annexure-IV
400KV CHORANIA / 400KV / 400KV KOSAMBA-1 87R 7UT612 V4.612-Mar-14
Var
/ 7:17:30 PM.779
t in ms
Cursor 1:
Measuring Signal
Instantaneous
28.5 IDiff-L3
R.M.S.
221.66 mI/InO
Trigger
12-Mar-14
7:17:30 PM.779
iL1-M1/ A
20
0
-20
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
t/s
-40
iL2-M1/ A
20
0
-20
t/s
-40
iL3-M1/ A
20
0
-20
t/s
-40
3i0-M1/ A
20
0
-20
t/s
-40
iL1-M2/ A
0
-10
t/s
iL2-M2/ A
0.025
-0.000
-0.025
-0.050
t/s
iL3-M2/ A
0.025
-0.000
-0.025
-0.050
15-Mar-14 / 7:56:25 AM
SIGRA 4.51
t/s
C:\USERS\ABC\DESKTOP\CHO. OCC. 12032014\400KV CHORANIA SS 12.3.14\BUS - 2\400KV KOSAMBA-1\87\550
400KV CHORANIA / 400KV / 400KV KOSAMBA-1 87R 7UT612 V4.612-Mar-14
Var
/ 7:17:30 PM.779
3i0-M2/ A
0
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
-10
t/s
IDiff-L1/ I/InO
0.20
0.10
t/s
0.00
IDiff-L2/ I/InO
0.20
0.10
t/s
0.00
IDiff-L3/ I/InO
0.20
0.10
t/s
0.00
IRest-L1/ I/InO
0.20
0.10
t/s
0.00
IRest-L2/ I/InO
0.20
0.10
t/s
0.00
IRest-L3/ I/InO
0.20
0.10
t/s
0.00
Flag Lost
>Trig.Wave.Cap.
FltRecSta
Relay TRIP
Relay PICKUP
Diff picked up
Diff> TRIP
Diff>> TRIP
64R FAULTY
15-Mar-14 / 7:56:25 AM
SIGRA 4.51
t/s
C:\USERS\ABC\DESKTOP\CHO. OCC. 12032014\400KV CHORANIA SS 12.3.14\BUS - 2\400KV KOSAMBA-1\87\550
400KV CHORANIA / 400KV / 400KV KOSAMBA-1 MAIN-2 DPS 7SA612
12-Mar-14
V4.7 Var
/ 7:19:31 PM.699
t in ms
Cursor 1:
Measuring Signal
Instantaneous
0.0 iL3
R.M.S.
0.4931 kA
0.3798 kA
Trigger
12-Mar-14
7:19:31 PM.699
iL1/ A
500
0
-500
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
-1000
t/s
iL2/ A
500
0
-500
-1000
t/s
iL3/ A
500
0
-500
-1000
t/s
iE/ A
500
0
-500
-1000
t/s
uL1/ V
10000
0
-10000
-20000
t/s
uL2/ V
10000
0
-10000
-20000
t/s
uL3/ V
10000
0
-10000
-20000
t/s
15-Mar-14 / 7:31:01 AM C:\USERS\ABC\DESKTOP\CHO. OCC. 12032014\400KV CHORANIA SS 12.3.14\BUS - 2\400KV KOSAMBA-1\MAIN-2\1460
SIGRA 4.51
400KV CHORANIA / 400KV / 400KV KOSAMBA-1 MAIN-2 DPS 7SA612
12-Mar-14
V4.7 Var
/ 7:19:31 PM.699
uSYN2/ V
10000
0
-10000
-20000
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
t/s
>Trig.Wave.Cap.
Flag Lost
SOF O/CtripL123
O/C PICKUP
Power Swing
Pow. Swing TRIP
Dis.Pickup L1
Dis.Pickup L2
Dis.Pickup L3
Dis.Pickup E
Dis. forward
Dis. reverse
Dis.Gen. Trip
Dis.Trip 1pL1
Dis.Trip 1pL2
Dis.Trip 1pL3
Dis.Trip 3p
Dis.TripZ1/1p
Dis.TripZ1B1p
Dis.TripZ2/1p
Dis.TripZ2/3p
Dis.TripZ3/T3
Dis.TRIP 3p. Z4
>CB1 Pole L1
>CB1 Pole L2
>CB1 Pole L3
>CB1 Ready
Relay PICKUP
Relay PICKUP L1
Relay PICKUP L2
Relay PICKUP L3
Relay PICKUP E
t/s
15-Mar-14 / 7:31:01 AM C:\USERS\ABC\DESKTOP\CHO. OCC. 12032014\400KV CHORANIA SS 12.3.14\BUS - 2\400KV KOSAMBA-1\MAIN-2\1460
SIGRA 4.51
400KV CHORANIA / 400KV / 400KV KOSAMBA-1 MAIN-2 DPS 7SA612
12-Mar-14
V4.7 Var
/ 7:19:31 PM.699
Relay TRIP L1
Relay TRIP L2
Relay TRIP L3
Relay TRIP
>Manual Close
FltRecSta
DisTRIP3p. Z1sf
DisTRIP3p. Z1mf
DisTRIP3p.Z1Bsf
DisTRIP3p Z1Bmf
AR CLOSE Cmd.
AR Close1.Cyc1p
BF T1-TRIP L123
AR Close1.Cyc3p
Uph-e>(>) TRIP
Uphph>(>) TRIP
Line closure
1pole open L1
1pole open L2
1pole open L3
SF6 GAS LO
M1 OPTD
O/V M1 OPT
COX CH2
COX CH1
CB L/O
LBB&BBoptd
3PH TRIPop
DTS CH-2
TC2unhealt
DT RCV CH2
M2 OPTD
-0.4
-0.2
-0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
t/s
15-Mar-14 / 7:31:01 AM C:\USERS\ABC\DESKTOP\CHO. OCC. 12032014\400KV CHORANIA SS 12.3.14\BUS - 2\400KV KOSAMBA-1\MAIN-2\1460
SIGRA 4.51
Limbdi 120314
SIGRA 4.4
Mundra 2
7SA522 V4.6 Var
7:21:56 PM.040
Trigger
3/12/2014
7:21:56 PM.040
iL1/kA
1.0
0.5
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
t/s
0.0
iL2/kA
1.0
0.5
t/s
0.0
iL3/kA
1.0
0.5
t/s
0.0
uL1/kV
200
100
t/s
0
uL2/kV
200
100
t/s
0
uL3/kV
200
100
0
- 2 -
t/s
Limbdi 120314
SIGRA 4.4
Mundra 2
7SA522 V4.6 Var
7:21:56 PM.040
L CB R opn
L CB Y opn
L CB B opn
M1carr rec
M1 Trip
A/R oprtd
OV stg1&2
STUB oprtd
DT recev
M2 optd
BB oprtd
LBB oprtd
TBC R opn
TBC Y opn
TBC B opn
A/R unscs
Diff optd
REF optd
BUimpd opt
M2carr rec
Z1 trip
Z1B trip
Z2 trip
Z3 trip
Z5 trip
SOTF trip
Power swn
E/F trip
0.5
1.0
1.5
2.0
- 3 -
2.5
3.0
3.5
4.0
4.5
t/s
Bhachau 400-220 13072013 / 400kV
SIGRA 4.4
BAY 407 Ranchodpura L 1
B407 21
7:21:56 PM.449
Trigger
3/12/2014
7:21:56 PM.449
iL1/kA
2
1
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
t/s
0
iL2/kA
3
2
1
t/s
0
iL3/kA
2
1
t/s
0
uL1/kV
200
100
t/s
0
uL2/kV
200
100
t/s
0
uL3/kV
200
100
t/s
0
iEp/A
75
50
25
0
- 2 -
t/s
SIGRA 4.4
Bhachau 400-220 13072013 / 400kV
BAY 407 Ranchodpura L 1
B407 21
7:21:56 PM.449
DT Send
M Rph Open
M Yph Open
M Bph Open
M1 CR
M1 Trip
A/R Optd
O/V Optd
STUB trip
DT recieve
M2 Trip
BB Trip
LBB optd
TieRph Opn
TieYph Opn
TieBph Opn
Z1B Trip
Z1 strt
Z2 Strt
Z3 Strt
Z4 Strt
Z5 Strt
SOTF Trip
Z1 trip
Z2 trip
Z3 trip
Z4 trip
Z5 trip
PSD
M A/R Blk
T A/R Blk
DT Send
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
t/s
M A/R Unsu
T A/R Unsu
86A Trip
86B Trip
DEF Trip
Car Out
TieLBBOptd
M2 CR
- 3 -
t/s
Limbdi 120314
SIGRA 4.4
Vadavi 2
7SA522 V4.6 Var
7:21:55 PM.740
Trigger
3/12/2014
7:21:55 PM.740
K1:iL1/A
200
100
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
t/s
0
K1:iL2/A
200
100
t/s
0
K1:iL3/A
200
100
t/s
0
K1:uL1/kV
100
t/s
0
K1:uL2/kV
100
t/s
0
K1:uL3/kV
100
t/s
0
K2:iEp/A
200
100
0
- 2 -
t/s
Limbdi 120314
SIGRA 4.4
Vadavi 2
7SA522 V4.6 Var
7:21:55 PM.740
M CB R opn
M CB Y opn
M CB B opn
M1 Car Rec
M1 trip
A/R op
O/V optd
Teed Op
DT rec
M2 carr re
M2DistOpt
B.B trip
M/T LBB op
TBC R opn
TBC Y opn
TBC B opn
0.25
0.50
0.75
1.00
- 3 -
1.25
1.50
1.75
t/s
Bhachau 400-220 13072013 / 400kV
SIGRA 4.4
BAY 404 Mundra Line 1
B404 21
7:21:56 PM.765
Trigger
3/12/2014
7:21:56 PM.765
K1:iL1/kA
3
2
1
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
t/s
0
K1:iL2/kA
3
2
1
t/s
0
K1:iL3/kA
3
2
1
t/s
0
K1:uL1/kV
300
200
100
t/s
0
K1:uL2/kV
300
200
100
t/s
0
K1:uL3/kV
300
200
100
t/s
0
K2:iEp/kA
3
2
1
0
- 2 -
t/s
SIGRA 4.4
Bhachau 400-220 13072013 / 400kV
BAY 404 Mundra Line 1
B404 21
7:21:56 PM.765
M Rph Open
M Yph Open
M Bph Open
M1 CR
M1 Trip
A/R Optd
O/V Optd
STUB trip
DT recieve
M2 Trip
BB Trip
LBB optd
TieRph Opn
TieYph Opn
TieBph Opn
Z1B Trip
Z1 strt
Z2 Strt
Z3 Strt
Z4 Strt
Z5 Strt
SOTF Trip
Fuse Fail
Z1 trip
Z2 trip
Z3 trip
Z4 trip
Z5 trip
PSD
M A/R Blk
T A/R Blk
DT Send
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
2.00
2.25
2.50
2.75
t/s
M A/R Unsu
T A/R Unsu
86A Trip
86B Trip
DEF Trip
Car Out
TieLBBOprd
M2 CR
- 3 -
t/s
JETPUR S/S
SIGRA 4.4
7:21:04 PM.833
Trigger
3/12/2014
7:21:05 PM.334
LINE_A_IL1/kA
1.5
1.0
0.5
0.0
0.5
1.0
1.5
2.0
2.5
0.0
0.5
1.0
1.5
2.0
2.5
0.0
0.5
1.0
1.5
2.0
2.5
0.0
0.5
1.0
1.5
2.0
2.5
0.0
0.5
1.0
1.5
2.0
2.5
0.0
0.5
1.0
1.5
2.0
2.5
0.0
0.5
1.0
1.5
2.0
2.5
t/s
0.0
LINE_A_IL2/kA
1.5
1.0
0.5
t/s
0.0
LINE_A_IL3/kA
1.5
1.0
0.5
t/s
0.0
LINE_A_IN/kA
1.5
1.0
0.5
t/s
0.0
LINE_UL1/kV
200
100
t/s
0
LINE_UL2/kV
200
100
t/s
0
LINE_UL3/kV
200
100
0
- 6 -
t/s
JETPUR S/S
SIGRA 4.4
7:21:04 PM.833
MAIN CB R OPN
MAIN CB Y OPN
MAIN CB B OPN
M2 CARR RECVD
AR_CLOSE
TOV1-TRIP
TBC CB R OPEN
TBC CB Y OPEN
TBC CB B OPEN
ZM01-TRIP
ZM02-TRIP
ZM03-TRIP
ZM04-TRIP
SOTF-TRIP
ZCOM-TRIP
DT_SEND
PHS-STFWL1
PHS-STFWL2
PHS-STFWL3
PHS-STFWPE
PSB-OPTD
VTS
TOV1-TRIP
TOV2-TRIP
TOV START-1/2
CARRIER_REC
MAIN CB R OPN
MAIN CB Y OPN
MAIN CB B OPN
SOTF INI
TBC CB R OPEN
TBC CB Y OPEN
0.0
0.5
1.0
1.5
2.0
2.5
0.0
0.5
1.0
1.5
2.0
2.5
t/s
TBC CB B OPEN
REACTR TROUBE
M2 CARR RECVD
TR_R_MAIN_CB
TR_Y_MAIN_CB
TR_B_MAIN_CB
CARR_SEND
TR_R_TBC_CB
TR_Y_TBC_CB
TR_B_TBC_CB
TRIP_3P_MAIN
TRIP_3P_TBC
- 7 -
t/s
Limbdi 120314
SIGRA 4.4
Mundra 1
7SA522 V4.6 Var
7:10:41 PM.692
Trigger
3/12/2014
7:10:41 PM.692
K1:iL1/kA
1.5
1.0
0.5
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
0.25
0.50
0.75
1.00
1.25
1.50
1.75
t/s
0.0
K1:iL2/kA
1.5
1.0
0.5
t/s
0.0
K1:iL3/kA
1.5
1.0
0.5
t/s
0.0
K1:uL1/kV
200
100
t/s
0
K1:uL2/kV
200
100
t/s
0
K1:uL3/kV
200
100
t/s
0
K2:iEp/kA
1.5
1.0
0.5
0.0
- 2 -
t/s
Limbdi 120314
SIGRA 4.4
Mundra 1
7SA522 V4.6 Var
7:10:41 PM.692
L CB R opn
L CB Y opn
L CB B opn
M1carr rec
M1 Trip
A/R oprtd
OV stg1&2
STUB oprtd
DT recev
M2 optd
BB oprtd
LBB oprtd
TBC R opn
TBC Y opn
TBC B opn
A/R unscs
Diff optd
REF optd
BUimpd opt
M2carr rec
Z1 trip
Z1B trip
Z2 trip
Z3 trip
Z5 trip
SOTF trip
Power swn
E/F trip
0.25
0.50
0.75
1.00
- 3 -
1.25
1.50
1.75
t/s
Annexure-V
PMU Plots
Annexure-V to the Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 1
Annexure-V to the Report on Blackout at CGPL Mundra (UMPP) at 19:22 hrs, 12-March-2014.
Page 2

Personal Risk Management for Volunteers

Night Owls Peter Piper Lock In Permission Slip

details. - Choice Travel

College Newsletter Friday 30th January 2015

Mission Trip FAQs

Section 8.3 - Problem Solving

Decision No. CIC/YA/A/2014/000747 dated 30-01

golden jubilee year - Government Polytechnic, Rajkot

Community Highlights - Saratoga Federated Church

Monthly Calendar - Frank C. Martin International K