Electric (Utility) Distribution Systems
Take-Home Exam

The construction of a new major seaport has encouraged additional new load to develop in an area that had been undeveloped previously. The seaport and supporting industries are expected to add a total of 40 megawatts to a 15 square-mile area over the next 10 years. There are two lightly loaded (60% at peak) 138 kV lines, each of which can carry 280 MVA, in the vicinity of the seaport, but no distribution substations exist. There is also a moderately loaded 230 kV line (750 MVA capacity, 600 MVA peak loading) in the area. See map below. NewSeaportAreaExisting 138 kV LineExisting 138 kV LineExisting 230 kV Line
1. Propose a load forecasting methodology (informal, simple trending, sophisticated trending, simulation) that would be best to use for this scenario. Why did you choose the method you did?
2. What kinds of provisions should be made for automation of the distribution system (both at the time of construction and in the future)? Develop a distribution automation plan and explain why you are proposing the automation methods you have selected. Cite manufacturer equipment needed for your plan.
3. Determine an evaluation strategy for service transformers. Explain what cost values will be needed and how those values will be used to evaluate one service transformer design versus another. Use supporting data from manufacturers (Cooper, ABB, etc.).
4. Develop a conceptual design of distribution substation(s) needed for this system expansion. Show one-line diagrams and explain how the existing infrastructure must be modified to accommodate this/these substation(s). Explain why you chose the substation topology(ies) you did.