Palmer Street Substation
Palmer Street Substation, Palmer, MA
115-23kV Transformer and 23kV Regulator Install
The scope of work included the install of a new 115-23kV, 12/16/20 MVA transformer, 115kV 1200A circuit switcher, extension of 115kV Bus 1, (1) 23kV 1200A load break switch, 23V 1200A circuit breaker, and 23kV breaker disconnects. An alternate 23kV supply was also provided from the tertiary of Transformer #6, using existing cables, and (3) 23kV voltage regulators were installed into the existing 23kV supply cables.
Engineering, Design, and Construction Support Services Included:
- Removal of 13.2kV structures and foundations.
- Installation of foundations for the 115/ 23 kV transformer, (2) 115 kV 1200A circuit switchers, and steel dead end structure, (2) 23kV cable riser structures, (1) 23kV Voltage regulator, (1) 23kV, 1200A circuit breaker, and (1) 23kV air break switch.
- Conduits from the new equipment to the existing Trenwa system.
- Oil containment system in accordance with Client’s requirements for the new transformer.
- Installation of (1) 115kV tubular steel dead end and circuit switcher structure, (2) 23kV cable riser structures, (1) 23kV aluminum switch structure, and (1) 23kV voltage regulator structure.
- Removal of all equipment at the 13.2kV voltage fed by the 13.2kV winding of Transformer T5, except disconnect switches and VT’s.
- Installation of (1) new 115/23kV Power Transformer, 12/16/20 MVA, with LTC.
- Installation of (1) new 115kV, 1200A continuous circuit switcher, model 2020.
- Extension of 115kV Bus No. 1 ,using 795kcm AL conductor.
- Design of conduits, U/G duct banks, new control cables.
- Installation of (1) 23kV 1200A VCB, (6) new 23kV 1200A disconnect switches, (1) new 23kV 1200A group operated load break switch, (6) new 23kV 1200A disconnect switches to replace switches 81 and 82.
- Installation of (3) new GE JKW-6 600 current transformers and (3) new GE JVW-614,400:120 voltage transformers.
- Installation of (1) 3-Φ voltage regulator in the lower yard.
- Installation of SEL-351A relay, SEL-387 differential relay for primary protection of Transformer #T5.
- Installation of SEL-351-5 relay to serve as backup protection to the transformer.
- Installation of BE3-27 relay to provide dead bus transfer.
- Installation of undervoltage Dunco relays to also provide a bus transfer scheme between Transformer #1 (primary source) and Transformer #5 (secondary source).
- Design of 115/23kV protective relays, test switches, and control switches to be placed in 36” wide simplex panels.
- All new alarms that were placed in existing annunciator panels.
- New substation line sharing switch was installed to support new revenue metering.
- Installation of new socket-type TransData MkV revenue meter, meter cabinet, and meter test switch from new 23kV Transformer supply.
- Substation ground grid analysis.