Electrical Engineering - Power - Utility Distribution Systems Design Project
It's a bad day in Tampa! A tornado {we had enough hurricanes!!} hits Tampa and destroys the substation that supplies the USF campus. The 69 kV subtransmission line that loops through the substation was left undamaged, and will be used to supply the new substation which needs to be built to replace the destroyed one. At the same time as the tornado was destroying the substation, a massive swarm of PVC-eating subterranean termites ate through virtually all of the underground primary cable serving the campus. {I told you it was a bad day!!} And to make things worse, nobody can seem to find the engineering drawings that show how the primary circuits were designed. {See, those AutoCAD files really do need to be backed up!!}
Only a brilliant engineering student (that would be you) can save the day by designing a new substation and distribution primary system. So here's your task:
Phase 1: Substation
A 69 kV source configuration needs to be designed. When doing this, keep in mind what is existing and the reliability requirements of the campus and several hospitals served by the substation.
Two transformers (36 MVA each) are needed in the substation to step the voltage down to 13.2 kV. Three circuits must leave the substation (one heading west on Fletcher Ave., one heading east on Fletcher, and one heading north on 42nd St - across from Palm Ave.) to serve non-USF load. Those circuits are overhead on concrete poles, so were unaffected by the termites. You just need to provide breakers to supply these existing feeders. Additional underground circuits will need to be built to supply the USF campus.
Phase 2: Distribution Primary
Today, the USF campus has a peak load of 35 MW. The load forecast for the USF campus was also misplaced - probably with the feeder drawings... So a new load forecast needs to be developed. Somebody seems to remember an ultimate peak load for 42 MW for the whole USF campus many years in the future, so use that number and informal load forecasting methods to re-create the campus load forecast for a 10-year period. The number of feeders you choose to use, and the amount of load served by each feeder is up to you. Remember to be able to provide a backup source if a main source becomes unavailable. Propose a primary feeder layout using the map on the last page of this project description. The red square top and center of the map is the substation location. The red line running along Fletcher Ave. is the 69 kV subtransmission line.
Deliverables:
All students do these
Produce a one-line diagram of the substation you propose. Show as much detail as you think is necessary in a preliminary (planning) document. Clearly show how the 69 kV source is configured and the bus topology that you believe is most appropriate to use.
On the attached campus map, show the routing of the primary feeders. Estimate the size of the service transformers based on transformer sizes you see in the engineering portion of the campus. Each service transformer on campus has its kVA rating clearly shown by stickon labels displayed on the steel enclosure.
Show your load forecast for at least a 10-year period. Keep in mind vacant land when doing the forecast.
Provide calculations showing feeder loading and estimate what you believe is a reasonable load factor. Suggest some demand-side management techniques to improve the load factor.
Explain how the new system will be operated in the event of a subtransmission line or substation transformer failure. Also discuss breaker failure scenarios.
Students taking this course for graduate credit (or undergraduates seeking extra credit) do these in addition Add sectionalizing devices on the primary circuits as you see fit. Suggest researching "PMH switchgear" by S&C Electric Co. for the available hardware. Note which type (circuit configuration) of PMH switchgear you select on your feeder drawing.
Determine the size (in kcmil) and type (copper or aluminum) of underground cable to use for your primary circuits. Suggest researching the Okonite Company website for cable data.
Propose an expansion strategy if the USF campus grows faster than the load forecast suggests. This should address both the substation and the primary system.
Attachment:- Assignment File.rar