Map Tree Trim Year Grosse Pointe Sub: 2011 Average Last Pole top - - PowerPoint PPT Presentation

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City of Grosse Pointe Woods

• # of Residents: 17,000 +
• # of Circuits: 16
• # of General Purpose Substations Feeding

Grosse Pointe Woods Area: 2

• Total Peak Load Served: 35 MVA
• Next Tree Trim Year Vernier Sub: 2013
• Tree Trim Year Grosse Pointe Sub: 2011
• Average Last Pole top Maintenance (PTM)

Year: 2007

Map

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Distribution Circuit

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Distribution Circuit 1481 Vernier Outages

Vernier Substation

• July 6 (11:59) through July 8 (21:35)

– July 6: No crews available due to the

• ngoing catastrophic storm.

– July 7: Crew Dispatched at 7:03

• Tree trim performed near Marter

and Alger.

• Replaced wire that came down.
• Attempted to close the breaker and

the breaker didn’t hold.

• Patrolled the circuit.
• 21:24 halted operations.

– July 8: Crew Dispatched at 7:19

• Attempt to close the breaker and

the breaker didn’t hold.

• Patrolled the circuit again.
• Started putting back small sections
• f the circuit at a time.
• Breaker held and restored all

customers at 21:35.

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Distribution Circuit 1481 Vernier Outages

Vernier Substation

• August 29 (12:56) through (20:00)

– August 29: Crew Dispatched at 13:12

• Reason: DTE Contract tree trim

crew working at a hazardous tree site near Hampton and Charlevoix. A rotted out limb came down on the wires and caused outage.

• The branch was removed 14:38.
• Attempt to close the breaker and

the breaker didn’t hold.

• Misoperation on reclosing relay

suspected.

• Started putting back small sections
• f the circuit at a time.
• Breaker held and restored all

customers at 20:00. Fuse

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Distribution Circuit 1481 Vernier Outages

Vernier Substation August 29 – What should have happened. – Reason: DTE Contract tree trim crew working at a hazardous tree site near Hampton and Charlevoix. A rotted out limb came down on the wires and caused outage. – The relaying at Vernier Substation opens the breaker. – The fuse on Goethe, south of Hampton blows. – In less than a second the reclosing relay should sense that the fault has been cleared and closes the breaker. – The outage should be contained to the residents located on the south side of Hampton and on north side of Hollywood between Goethe and Charlevoix until 14:38 by installing a new fuse. Fuse

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Short Term Countermeasures for DC 1481 Vernier

Action: Replace Reclosing relay at Vernier Substation and inspect the breaker. Results:

• Relay Replacement & inspection completed on August 31, 2012

Action: Review Relaying scheme for DC 1481 Vernier Results:

• Relaying scheme review was completed on September 5, 2012

Action: Perform pole by pole circuit patrol on DC 1481 Vernier Results:

• Patrol completed August 12, 2012
• No Immediate line or pole top maintenance problems were found. However, a hazardous tree

location was discovered near Hampton and Charleviox. Action: Perform a infrared survey of DC 1481 Vernier Results:

• See next slide.

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Infrared Results:

• Summary of Hot Spots:

– Fuses: 4 – Transformer Connections: 1 – Total number of Hot spots: 5

• Three Locations:

– 1334 Anita – 1383 Anita – 1828 Anita

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Longer Term Countermeasures for Grosse Pointe Woods

• A 30+ person committee is working on a long term Reliability Plan of all the Grosse Pointes.

– DTE Energy has begun a cross functional analysis to identify any potential unforeseen issues that would affect the reliability in the greater Grosse Pointe community.

• Perform relay studies on all circuits in Grosse Pointe Woods by the end of 2012.
• Fix Trunk line issues discovered during manhole inspections by the end of 2013.
• Have Breaker inspections performed on breakers at Vernier and Grosse Pointe substations

by the end of 2013.

• Two large projects to split circuits.

Splitting of DC 1481 Vernier

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Vernier Substation

New Circuit Work to be done:

• Install new breaker at Vernier Substation.
• Install 1,100 feet of underground cable.
• Install 100 feet of conduit.
• Reconductor 3,100 feet of overhead wire.

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Splitting of DC 1130 Grosse Pointe

New Senior Living Complex Grosse Pointe Substation

New Circuit Work to be done:

• Use an existing breaker at Grosse Pointe Substation.
• Install 1,100 feet of underground cable.
• Install 900 feet of conduit.
• Reconductor 3,800 feet of overhead wire.

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