ECE 562 - Spring 2020

Project 2 - Due Feb 11

You may use any power flow software you wish. However, if you don't use MATPOWER, then make a note on your project report describing the software that you used (e.g., PTI's PSS/E version xx, attached C code, attached Excel spreadsheet).

Branch Outage Effects on Branch Loading

  1. Choose any branch except those that would create a new island upon removal (e.g., a generator step-up transformer).
  2. Estimate the post-contingency branch MW loadings via the Line Outage Distribution Factors (LODF's). Note: the zip archive contains a MAT file for MATLAB, and an ASCII file. Both files have a 78x78 table of LODFs. After unzipping the archive, you can use "load lodf_esca64" to import the "d" matrix containing the LODFs as formulated in lecture. I decided to include columns for all branches, even though some may be all zero.
  3. Calculate the actual post-contingency branch MVA loadings via Newton-Raphson power flow "runpf('esca64_n')" as done in the first assignment.
  4. Compare your LODF based branch loadings to your actual NR power flow based branch loadings and submit the deliverables below.

Deliverables

  1. Brief description of project.
  2. Short description of your simulation, including solution summary (e.g., Newton-Raphson power flow converged in X iterations), list of active control devices (e.g., Qgen limits enforced, etc.), branch outaged (from bus number, to bus number).
  3. Table with the post-contingency top 10 most heavily-loaded branches (measured in loading percentage -- ignore the direction) based on the actual loading determined by power flow. Your table should include the following columns:
    1. Branch data (From, To, MVA rating, pre-contingency MVA flow)
    2. LODF
    3. Estimated post-contingency MW flow from LODF calculation
    4. Actual post-contingency MVA flow from power flow
    5. Estimated post-contingency percentage loading from LODF calculation
    6. Actual post-contingency percentage loading from power flow
    7. Post-contingency percentage loading error: estimate - actual, e.g., 84%est - 87%act = -3% error)
  4. Table with the post-contingency top 10 largest magnitude estimation errors (measured in percentage loading error). Rank them based on the magnitude of the error, but include the sign so that it's clear which percentage loadings were underestimated and which were overestimated. Your table should include the same ten columns as the previous table.
  5. Brief discussion of your results, including answers to the following questions:
    1. Do LODF-based calculations accurately predict the actual branch flows? Why?
    2. Are there any significant errors in the LODF-based estimates of branch loading levels? Where?
    3. What do you think causes the errors?
    4. Does the location of a monitored branch relative to the branch outage affect the errors? How?
    5. Did you notice anything else?
  6. All students must submit the code (MATLAB, C, Excel spreadsheet, etc.) they used to calculate the post-contingency branch flows as a section within the report. Then, the report file must be submitted via SafeAssignment on Blackboard. Main Campus students also must submit a hardcopy report at the beginning of class.

Updated 5 Feb 2020