The substation design presented a unique challenge as the addition to the low side had separate power purchasers, while the delivery to the POI was through a shared transformer and five-mile transmission line. In addition, the wind farm had to operate as a single entity in terms of meeting voltage schedule of the transmission owner at the POI while also having the functionality of handling separate active power curtailment set-points from the independent system operator.
Ulteig’s support of a new distribution substation site and 43.8 kV transmission tap line in Buchanan, Stutsman County, North Dakota, involved performing a title search, the development of a landowner database and the creation of a landowner aerial map for the route.
Ulteig negotiated easements with landowners along the 3.5-mile route. The team also completed a land value analysis within the project corridor and drafted easement documents and legal descriptions. Finally, the team successfully negotiated and secured signatures from all landowners, acting as liaison during construction and providing project deliverables to the Central Power Electric Cooperative organization.
The collection system design involved optimizing the route so as to provide the best possible option for both the client and landowners. The 345kV/34.5kV substation contained four feeders, and it was designed to owner standards. Ulteig also provided civil engineering services including access roads, crane access routes, crane pads, delivery flow plan, intersection improvements, laydown yard, substation side, and yard site design services.
Designed wind farm 345-34.5kV substation and serviced twelve (12) 34.5kV feeders combined into six (6) feeder circuit breakers with space for additional two (2) total VAR support positions.
The two (2) 34.5kV buses were separated by a normal open MOD switch bus tie. The 345kV portion of the station was a low-profile, open air design, consisting of one (1) 345kV line termination, three (3) 345kV group operated disconnect switches, two (2) 345kV SF6 power circuit breakers, three (3) 345kV capacitive voltage transformer, and two (2) 345-34.5kV main power transformers.
A prefabricated control enclosure housed the relay panels, digital fault recorder (DFR) panel, control equipment, and supervisory control and data acquisition (SCADA) and communication equipment.
These projects carried very aggressive timelines and required design work commence as soon as possible. Engineering design included replacement of existing QEI SCADA remote terminal units (RTUs) and the existing Mehta-Tech digital fault recorders (DFRs) at the Sidney and Stegall 345kV substations. Additional engineering included replacement of protective relays and power-line carrier transmitter/receivers at the six terminals of the Laramie River to Sidney, Sidney to Stegall, and Stegall to Laramie River 345kV transmission lines.
Engineering and construction were originally to be completed in two phases. The first phase was engineering and construction of the two SCADA RTU replacements and Mehta-Tech digital fault recorder replacements. These replacements were to be completed without taking any transmission line outages. Engineering was to begin immediately upon project award followed by construction. The second phase of the project was to replace the six protective relay sets. Engineering was to begin upon completion of Phase 1 installation and check-out, and after the “issued for construction” drawings were converted to as-built drawings. This would allow sufficient time for design of the protective relay replacement drawings prior to the line outages in the spring of 2015.
Ulteig engineers had a unique idea that ultimately transformed the engineering and construction delivery of the project and better positioned the client to be successful in completing the line relay replacements within the scheduled six-week outage. The shift in project delivery was to complete both Phase 1 and 2 simultaneously. The proposal was to design and install all new relay control panels fitted with the necessary components per substation. The new panels were designed to allow field technicians to abandon a majority of the existing panels and equipment in place and reduce the amount of demolition and panel connections to the existing panels. This allowed for all of the engineering and panels to be procured in the fall/winter of 2014 and installed and functionally tested in the winter of 2015. As a result, a great deal of time was saved during the scheduled outage by not having to mount new components in existing panels. Also, the time consuming demolition of existing relay control panels and equipment along with could then be completed after the substations have been energized as a majority of the components in the panels had been obsolete.
These projects demonstrated Ulteig’s ability to provide value added engineering solutions to our client and our capacity to complete engineering design work on time and with a high degree of accuracy.
Minnkota Power Cooperative (MPC) partnered with Ulteig to design its new 115/25 kV substation and associated transmission line upgrade in West Fargo, North Dakota. The project involved adding a new substation to accommodate future transmission feed upgrades to 115 kV. Minnkota and Ulteig explored new materials and products for fencing and electrical materials. They also created multiple 3D renderings of the proposed project that were used for permitting and city approval of the project.
The Veteran’s Boulevard project is worthy of special recognition for going beyond the basic design for supplying power to customers. New construction materials and design methodologies were incorporated while the team innovated new ways to allow for system expansions and upgrades for years to come. The team also successfully reduced the impact on neighboring transmission and distribution lines, helping to minimize outages and costly system rework. Carefully incorporating the new design elements according to MPC and Cass County Electric Cooperative (CCEC) standards will reliably supply power to the greater Fargo community while avoiding issues with aesthetic impact and facilitating the inclusion of new commercial and residential development.
“Ulteig has continually met or exceeded all our expectations, and this project was no different,” said a representative from Minnkota Power Cooperative who worked closely with us on the project. “The team was instrumental in helping us align our own design standards with the city’s aesthetic requirements.”