GATE EE 2014 Set 3 — Question 26
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Power Systems → Per-Unit System & Load Flow → Gauss-Seidel & Newton-Raphson
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Question
A 183-bus power system has 150 PQ buses and 32 PV buses. In the general case, to obtain the load flow solution using Newton-Raphson method in polar coordinates, the minimum number of simultaneous equations to be solved is __________.
Correct answer
332 to 332
Solution
In a power system with buses, let be the number of PQ buses and be the number of PV buses. One bus is designated as the slack bus.
Total buses .
PQ buses .
PV buses .
Slack bus = .In the Newton-Raphson method using polar coordinates:
Total buses .
PQ buses .
PV buses .
Slack bus = .In the Newton-Raphson method using polar coordinates:
1.The number of real power () equations is because the slack bus power is not an independent variable. .
2.The number of reactive power () equations is equal to the number of PQ buses, as voltage magnitude is fixed for PV and slack buses. .
Total number of simultaneous equations = .Continue learning with Success Tracker
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