Assignment:
Assignment Problems
Design a power system which feeds the combined loads of 700 MW and 500 MVAR. Your proposed power system may include any number of buses, any number of transmission lines, and any number of generators and loads. However, you need to justify and comment why you have
chosen such a configuration of your proposed system.
Apply a three-phase symmetrical fault between a bus to ground and perform the following:
Step 1: Calculations
1. Draw the schematic of your proposed power system with appropriate values of parameters and reasonable justification for your design.
2. Find the fault current, bus bar voltages, and line currents using bus admittance matrix approach.
You can assume the fault impedance as any standard value as you want.
3. Find the fault current, bus bar voltages, and line currents using bus impedance matrix approach.
4. Compare the results of part 3 with those from part 2 and comment on the results.
Step 2: Simulations
You may use PSSE software to perform the following tasks. Use the data calculated in Step 1 for the power system and perform the following tasks. See Lab 0 and Lab 2-Preliminary in Learning Material/ Lab Materials in Blackboard for the outlines on how to use PSSE to perform these tasks.
5. Create the system (new case) in PSSE, with input data from Step 1. (snapshot of schematic diagram in PowerWorld is needed)
6. Run the program to compute fault current and bus voltages during a three-phase fault at the appropriate bus you have chosen in Step 1 Assume 1.0 per-unit prefault voltage. Neglect prefault load currents and all losses.
7. Compute the positive-sequence bus impedance matrix, bus admittance matrix and line currents.
8. Compare the results of the fault current and bus voltages with calculations in Step 1. (comment on the results)
9. Compare the results of the bus impedance matrix, bus admittance matrix and line currents with the calculations in Step 1. (comment on the results)
10. Build the dynamical model of your proposed power system and perform dynamic simulation and three-phase short circuit fault analysis to obtain the bus voltage profile, rotor angle and speed deviation responses of generators.
Step 3: Research and Discussions
11. For your proposed power system, perform some research and discuss the improvements on stability, reliability, security, and the cost of your design.