Case Study

•Consider a power station that delivers a source with the voltage, Vs= 275 kV and current, Isof 1200 A at 60 Hz to a city that is 420 km away from the power station.

•A transformer located 210 km away from the station was proposed to maintain the voltage at 220 kV as the minimum voltage delivered to the city, with a peak current, IR, of 1000 A.

 

• Design this above system taking into consideration the following:

– Transmission line characteristicsincluding efficiency and voltage regulation. Set up specificationsfor the transmission line in terms of conductors (resistance; inductance; capacitance); insulators; towers; etc. You may use tables A.3 and A.4 from the textbook for the above reason.

– Substation/transformer turns ratio; configuration; and other specifications.

– Provide appropriate drawings.

 

 

 

>>>>>>>>>>>>>>>

Based onthe aboveassignment provide all protection features to the above transmission system taking into consideration the following facts:

–Protection against faults and lightning effects.

–Provide type and rating of protection equipment.

–Provide appropriate protection zoning.

–Provide circuit diagrams of the proposed relays.

–Briefly describe STATCOM (use the Internet).

–Briefly describe SCADA (use the Internet).

 

>>>>>>>>>>>>>>>>>>>>>>>

 

Submit a 10-page portfolio. The portfolio covers the entire case study.

•Basing on the case study: Continue designing the distribution and utilization system to provide electricity to the city. Take into consideration the following:

–Specifications of the distribution substation including number and type of transformers; configurations; neutral grounding, etc.

–The proposed topologies of distribution system for various types of loads: high- and low-density areas.

–Protection system for feeders and laterals with technical specifications.

–Capacitor banks: Read Example 14.3.

–Specifications of utilization transformers.

–Your design ends up with a typical home.

–Consider the following Example of a distributer as a problem to solve:

 

Example

•A single-phase distribution line 2 km long supplies a load of 120 A at 0.8 pf lagging at its far end and a load of 80 A at 0.9 pf lagging at its midpoint. Both power factors are referred to the voltage at the far end. The impedance per kilometer (go and return) is 0.05 + j0.1 Ohm. If the voltage at the far end is maintained at 230 V, determine the following:

–Voltage at sending end

–Phase angle between the voltages at both ends.

–Basing on current, classify the loads (residential, commercial, or industrial) and identify the protection requirements of the load.

–Provide appropriate drawing.