T I L L A M O O K P E O P L E ’ S U T I L I T Y D I S T R I C T
DISTRIBUTION FEEDER FAULT ANALYSIS
SCADA TO DG SITES
DIGESTER MW AND MVAR
INSTANTANEOUS READINGSFROM SEL 751 RELAY
TRASK SUBSTATION LOADINGDO NOT WANT TO FEED INTO 115 KV
FAULT LOCATOR TOOL DEVELOPED BY GIS SPECIALIST
CAR HIT POLE EVENT ANALYSIS
W I L S O N R I V E R S U B S T A T I O N E V E N T O N 9 - 2 - 1 3
WILSON RIVER SUBSTATION, CIRCUIT 63
Car Pole Accident
Olsen Rd.Recloser
Misty MeadowsGeneration
SCADA ALARMS DURING EVENTNOTE: DEVICE TIMES ARE NOT
SYNCHED
DG on adjacent circTripped Open
Olsen Rd. RecloserOperations
Ckt 63 RecloserLocks Out
SOE FROM SUBSTATION RECLOSER
OLSEN RD. RECLOSER OPERATIONS
NEXUS 1500 METER ON SUBSTATION BUS
A PHASE CURRENT – 2 OPERATIONS OF RECLOSER
3RD INTERRUPTION – MUCH HIGHER FAULT CURRENT
SEL 751 AT MISTY MEADOWS GENERATION 480 VOLT BUS
MAX FLT I = 3078 AMPS AT ACCIDENT SITE
SO HOW DID WE GET 4178 AMPS ON THE CIRCUIT 63 SEQUENCE OF EVENTS FILE?
SYNERGI PREDICTS A FAULT OF THIS MAGNITUDE SHOULD BE CLOSER IN TO
THE SUBSTATION
THIS IS SECTION OF LINE THAT SYNERGIPREDICTED THE FAULT SHOULD BE IN
A SHARP EYED OPS SUPV. FOUND BURN MARKS IN THIS VICINITY. LONG SPANS
DUE TO 115 KV UNDERBUILD
ELBOW FAILURE ON UG
SCADA ALARM AT 17:10 INDICATES FAULT ON NESTUCCA FEEDER 39
FIRST STEP IS TO CONNECT TO FORM 6 RELAY OVER ETHERNET – SEQ COORD. MEANS ANOTHER DEVICE OPERATED
OSCILLOGRAPHIC FILE FROM THE FORM 6 RELAY – PEAK CURRENT =1737 A
1737 X .707=1228 A RMS
FAULT LOCATION TOOL THAT GIS SPECIALIST MADE – FLT I FROM SYNERGI PROTECTION STUDY
FAULT WAS ON SINGLE PHASE UG IN SUBDIVISION – ELBOW FAILED
EXTENT OF FEEDERPOSSIBLE LOCATIONS ON MULTIPLE BRANCHES
FIRST RAIN AFTER DRY SUMMER
T I LLAMOOK PEOPLE’S UT I L I TY D ISTR ICT
FIRST INDICATION OF PROBLEMSCADA SHOWS FAULT ON CKT. 64
NEXUS 1500 ON SUB BUS
ZOOM IN ON PHASE A AND B CURRENTS
THE 3 PHASE CURRENTS ON CIRCUIT 64
COMPARE WAVEFORMS TO FORM 62ND PHASE GETS INVOLVED
OUTAGE REPORT SHOWS INSULATOR FLASHED OVER
PROBLEMS AT TCCA BOILERTCCA=T I LLAMOOK CHEESE FACTORY
FORM 6 OSCILLOGRAPHPEAK CURRENT = 3820 AMPSRMS CURRENT = 2700 AMPS
NEXUS 1500 ON SUB BUS
NEXUS FAULT CURRENT IS CLOSE TO FORM 6 VALUE = 3900A X .707=2757 A,
NOTE DROP IN LOAD
FROM SYNERGI, FAULT CURRENT AT BOILER MATCHES MEASURED FAULT I
FAULT LOCATOR TOOL PRETTY CLOSE
TREE THROUGH LINEMOHLER CIRCUIT 91
RECLOSER AT SUB SHOWS 428 A FAULT CURRENT ON C PHASE
OSCILLOGRAPH FROM FORM 6 SHOWS FOUR CYCLES OF FAULT CURRENT
4 CYCLES = .066 SEC.
FAULT BLEW A 15 A FUSE AT FISH HATCHERY
TCC CURVE SHOWS THAT 15 A FUSE SHOULD BLOW IN .06 SEC. AT 425 AMPS
FAULT LOCATOR TOOL TURNED OUT TO BE FAIRLY ACCURATE
Fuse Blew Here
Tree throughLine Here
SYNERGI PREDICTS 411 AMPS FAULT CURRENT AT THIS LOCATION
F A U L T E V E N T O N 1 1 - 9 - 1 5
STARLING BRINGS DOWN BLUE HERON
TUESDAY MORNING AT 8:20 AM
• Public Relations called Operations to find out if a breaker operated at Wilson River Substation• The Mill in town called to report a power dip
• SCADA showed that Circuit 61 had operated and Circuit 62 (Mill Feeder) saw current above Min Trip
ENGINEERING CONNECTED TO FORM 6 RECLOSER CONTROLS AT SUBSTATION VIA ETHERNET
• The Sequence of Events report from Ckt 61showed that the recloser tripped on Overcurrent, then reclosed and reset
ALSO DOWNLOADED OSCILLGRAPHYFILES FROM THE RECLOSERS
• Confirmed fault on Ckt 62
CONTINUATION OF WAVEFORM ON PRIOR SLIDE
• Note that second phase gets involved in fault in the last couple cycles before interruption
AFTER THE RECLOSER RECLOSED THE TRANSFORMER MAGNETIZING CURRENT WAS PRESENT
• After a few cycles, the magnetizing current decayed to below the minimum pickup value
NEXUS 1500 METER MONITORING THE TRANSFORMER BUS GIVES A BETTER PICTURE OF THE EVENT
• Note that 2nd phase gets involved before breaker opens. And transformer inrush currents can be seen
ZOOMING IN TO PHASE B
• The recloser was open for 2010 ms (2 sec.)
PLUGGED FAULT CURRENTS INTO FAULT LOCATOR TOOL TO PREDICT LOCATION OF FAULT
• Area highlighted in red is most likely fault location
BLUE HERON RESTAURANT REPORTED HEARING A LOUD BANG – DEAD STARLING WAS FOUND AT
THE BASE OF A POLE NEAR THEM
Blue Heron
Dead Starling
Predicted Fault Location
IT IS QUESTIONABLE THAT THE STARLING CAUSED THIS FAULT
• Usually takes a bigger bird to cause a phase-to-phase fault
• Phase-to-phase fault current at location where starling was found did not match calculated fault current
• No burn marks from arcing were observed on the pole
A 10-15-15 FAULT WAS SIMILAR TO THIS ONE AND NO CAUSE WAS FOUND
(COMPARE TO SLIDE 36)
UG CABLE FAILUREL O C A T I O N P R E D I C T I O N G O O D
F L T I C O N T R I B U T I O N F R O M M I L L M O T O R S
SCADA ALARMS
INTERROGATE FEEDER BREAKERS
• Form 6 Recloser Controls did not show anything in Sequence of Events Files
• But they did capture Oscillographic waveforms• The fault was on Circuit 63. The Form 6 on Ckt 63
showed two Oscillographic events• First Event:
CIRCUIT 63 – SECOND EVENTLINEMAN REFUSED THE RISER POLE
CIRCUIT 62 CONTRIBUTED FAULT CURRENT DUE TO LARGE MOTOR LOAD
• Note that current is going in the opposite direction as the current in Ckt 63
FROM PQ METER ON SUB BUSRMS VALUE OF FAULT CURRENT IS CLOSE TO WHAT THE FORM
6 SHOWS: 2165 A ON FORM 6, 2072 A ON NEXUSFAULT LASTED FOR 1.5 CYCLES = .0025 SEC
FAULT LOCATION PREDICTION NOT FAR OFF
Fault on UG Cable
SYNERGI PROTECTION STUDY PREDICTS MAX SLG FAULT CURRENT TO BE 2292 A AT
THIS LOCATION
30 A FUSE SHOULD BLOW IN .019 SEC. AT 2165 AMPS. 1.5 CYCLES = .025 SEC.
QUESTIONS?G A I L S H A W
G S H A W @ T P U D . O R G
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