ELEC4310 Power System Analysis Assignment 2
Load Flow Analysis
Submission due date: 4 pm Thursday 17th April 2025
P1 - Base Case Build and Study (35 Marks)
Build a typical 13-bus power system (Figure 1) in PSS/E and save it as “P1.sav” and “P1.sld” . System components should be positioned in the manner shown in Figure 1.
The 13-bus system has two voltage levels (66 and 138kV). Use two different colors for the bus and branches to differentiate.
Some input data for this power system is provided in “Transmission Network Data” section. Based on the system you have built:
1) Use the provided Python script. “RetrieveYbus.py” to obtain Y-bus of the system and export it in a .CSV file (name it “YMatrix.csv”). Include the Y-bus matrix in your report. To know details about the functions in “RetrieveYbus.py”, read Python API document.
2) Use Full Newton-Raphson method to conduct power flow study. Show the voltages at all buses in PSSE and include a screenshot in your report.
3) Create a new Python script. “P1.py” that opens the file “P1.sav” you have built in PSSE, solves power flow by Newton-Raphson method and retrieve bus voltages on command window. Include screenshots of Python script. and command window output in your report.
Note: It is required to implement the python script. in Python 2.7 (32 bit)
P2 Compensation (35 Marks)
1) Identify the bus no. with lowest voltage in the base case. Conduct Q-V analysis on the identified bus. Take screenshot of Q-V curve and include it in your report.
2) Name one method to increase the voltage magnitude at the lowest voltage bus identified in P2(1) to 1.0 p.u. Verify this method and provide justification in your report.
3) Obtain a new Y-bus by modifying the provided “RetrieveYbus.py” and conduct Q-V analysis again. Compare with results of P2(1) and discuss briefly.
4) Add renewable generation (wind or photovoltaics) at the lowest voltage bus and save the new case and diagram file as “P2.sav” and “P2.sld” . You can do so by adding a load component in PSSE and setting negative MW and Mvar values to mimic renewable generators. Briefly discuss the impact of adding one of the following extra renewable generations, once at a time.
a) A wind generator producing (30+2X) MW at power factor 0.9 lagging.
b) A PV generation of (30+2X) MW at unity power factor. Model the PV as a distributed load.
Note: “X” stands for the last digit of your 8-digit student number. If the last digit of your 8-digit student number is 0, then X is 10.
P3 Contingency Analysis (30 Marks)
An event that happens unplanned/unexpected is considered as a contingency. For example, the loss/failure of an electric asset or multiple assets (such as an outage of a transmission line or transformer). Such an event may cause detrimental consequences. Performing contingency analysis is therefore important to investigate potential outcomes of outage in existing power systems.
Apply one of the following contingency scenarios at a time, to the base case system in P1, and conduct contingency analysis by: (a) describing whether the system operates normally under this specific contingency condition; (b) including excel bar graphs of system voltage profile at all buses (compared with base case voltage profile), followed with brief discussion.
(1) Contingency scenario 1: Generator at bus 11 is out of service.
(2) Contingency scenario 2: Transmission line between bus 3 and 4 is out of service.
(3) Contingency scenario 3: All real power of loads throughout the system increases by 25% without any change in generations.
Transmission Network Data
System Base: 100 MVA, System frequency 50 Hz
(a) Single Line Diagram of the System
Figure 1. Single-line diagram of a 13-bus transmission system
(b) Load Data
(c) Generator Data
(d) Transformer Data
(e) Branch Data
IMPORTANT SUBMISSION INFORMATION
(a) All case (.sav) files, diagram (.sld) files, python (.py) scripts must be named appropriately. There should be one folder for each task. Compress all five folders in a single zip file, named
‘########_PSSE_files’, where ######## is your 8-digit student number.
(b) Your PSS/E report must be submitted to Blackboard directly in PDF version. The report itself should not be included in the zip file.
(c) Make sure you have answered all the questions.
(d) This report should be no more than 12 pages (one sided only, Times New Roman font size 12,
single line spacing with 2cm margin on all sides). Appendix does not count. You should place tables and graphs into the body of the report. All figures, tables and codes presented in the report are counted in the page limit.
(e) Report must include concise summary of results for each section, along with comments and discussions. It could be as short as one sentence or long as a paragraph.
(f) Place figures as close as possible to where you refer them to in the context.