Substations

Substation, Switchgear and Equipment Maintenance and Testing

Our engineers have completed substation testing and maintenance including power transformers, switchgear from 600 V to 35 kV, overhead and industrial switches, reclosers, relays, breakers and regulators for over 20 different utilities and industrial customers. Testing and maintenance services have included 34.5 kV – 230 kV oil circuit breaker testing and maintenance, including bushing power factor, ductor, time travel, speed adjustments and other tests associated with maintenance activities. Power transformer testing and maintenance for transformers up to 80 MVA and 230 kV LTC testing and maintenance and metal-clad breaker testing and maintenance.

Representative substation projects include:

D Street Substation

Doyon Utilities, Fort Richardson, Alaska

D Street Substation consists of a 34.5 kV substation with three breakers, a 47 MVA 34.5 / 12.47 kV transformer and eleven 12.47 kV breakers. The substation includes remote control and automation to the local emergency generation and integration with a remote substation over fiber-optic communications for emergency restoration. The project utilizes SEL-351S protective relays for the distribution feeders and SEL-311C relays for the 34.5 kV ties. The station uses SEL-734 meters for metering and SEL-3354 and SEL-2890 for automation and control. EPS provided the engineering design, EPC provided the construction and member company Specialty Engineering, Inc. (SEI) provided the commissioning services.

Arctic Warrior Substation

Doyon Utilities, Fort Wainwright, Alaska

This substation is a critical interconnection between the FWA generation and distribution feeders and the local utility’s transmission system. The substation consists of a 138 kV bay with a 20 MVA 138 / 12.47 kV transformer and eighteen 12.47 kV breakers. The station is configured as a double-ended station with a 2.0 MVA emergency generator. The substation includes remote control and automation to the local emergency generation and integration with the central power plant over fiber-optic communications and Wonderware interface. The project utilizes SEL-351S protective relays for the distribution feeders and SEL-311C relays for the 138 kV intertie. The station uses SEL-734 meters for metering and SEL-3354 and SEL-2890 for automation and control. The station includes automated demand management for load control, and differential protection to the 20 MVA power plant. EPS provided the engineering design, and SEI provided the commissioning services.

Diamond Ridge Substation

Homer Electric Association, Homer, Alaska

The Diamond Ridge Substation is a 115 kV main and transfer bus station with a 115 kV/ 69 subtransmission transformer and a 15 / 24.9 kVdistribution station transformer. The station serves as a critical switching station as well as a critical distribution source for the Homer area loads. The 115 kV main and transfer bus encompasses six breakers and utilizes SEL 487, SEL 311C and SEL-421 protective relays and an SEL-3354 for station automation. The distribution station includes 5 breakers and SEL-351S relays, SEL-487 relays and an SEL-3354 for station automation. The station was designed for extreme snow conditions that have been observed in the area. The project included extensive site work due to poor soil and permafrost conditions.

Protective Relaying and Automation Upgrades

Chugach Electric Association, Anchorage, Alaska

The Chugach Electric Association’s protective relaying and automation upgrades consisted of both the design and the subsequent project construction located at Chugach’s Beluga and Douglas Substations. The projects included the design and installation of protective relaying and automation on Chugach’s critical generation station and transmission system. All projects were completed in energized facilities without an outage. The projects included relaying upgrades on two 28 MW gas-fired turbines and station relaying on a 415 MW generation plant. The design was performed by Electric Power Systems (EPS) and the installation was performed by Electric Power Constructors (EPC).

Retherford Substation

Chugach Electric Association, Anchorage, Alaska

EPS completed the design and construction inspection for the new Retherford Substation in Anchorage. The substation consisted of two 100 MVA transformers, two 138 kV breaker and one-half bays and thirteen 34.5 kV breakers configured in a main and transfer bus scheme in metal-clad switchgear. EPS was responsible for the design of the substation civil work, bus layout, grounding and lighting. EPS was responsible for the design of the protective relay installation for the transmission lines, transformers and 34.5 kV feeders. EPS was responsible for the communications and SCADA interface with the Chugach control center. EPC completed the electrical testing and commissioning for the construction contractor. EPS completed the quality control inspection for the substation construction.

Postmark Substation

Chugach Electric Association, Anchorage, Alaska

EPS completed the design and construction inspection for the new Postmark substation in Anchorage. The substation consisted of two 14 MVA transformers, two 138 kV breakers and nine 12.47 kV breakers configured in a main and transfer bus scheme with a double-ended bus arrangement in metal-clad switchgear. EPS was responsible for the design of the substation civil work, bus layout, grounding, and lighting. EPS was responsible for the switchgear specifications and protective relaying arrangement. EPS completed the quality control inspection for the substation construction.

Woodinville Substation

BP Olympic Pipeline, Woodinville, Washington

EPS completed the design and construction inspection of the new Woodinville BP/Olympic station near Bothell, Washington. The substation consisted of four 4.16 kV feeders in metal-clad switchgear. The construction and commissioning of the substation was required to be completed within a single four day outage, and the design accommodated this restriction by pre-constructing a significant portion of the station prior to the outage.

EPS was responsible for the switchgear design and specifications, station layout and civil work, protective relaying settings, medium voltage and low voltage design, and arc flash calculations. EPS completed the quality control inspection, and all testing, commission, and startup for the substation construction.

Airai Substation

Palau Public Utilities Corporation, Koror, Palau

EPS completed the civil, structural and electrical design for the 34.5 / 12.47 kV Airai Substation. Project included concrete block control building, relaying and control panels, four 12.47 kV breakers, installation of controls and modifications for one 34.5 kV breaker and three 34.5 kV motor-operated switches and SCADA control and monitoring for the station. EPS provided the structure design, electrical service, grounding, protective relaying and controls design. EPS completed the installation and commissioning.

Cowlitz 115/230kV Substation Bank 6 Replacement

Tacoma Public Utilities, Tacoma, Washington

EPS provided structural engineering to add a new bank to this existing substation. It included adding a new 230 kV, 400 MVA power transformer and new 230 kV deadend structures. Existing lattice steel deadend structures were analyzed for attaching the new bay, and steel procurement documents were developed for the new structure. The transformer foundation was designed for High Seismic Level in accordance with IEEE 693-2005.