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IEEE 9-Bus Loadflow

This example shows a model of a 9-bus three-phase power system network. This example is based on an IEEE® benchmark test case, further details of which can be found in "Power System Control and Stability" by P. M. Anderson and A. A. Fouad (IEEE Press, 2003). Simscape™ initializes two of the generators to the specified powers and terminal voltages, and initializes the remaining swing bus generator to meet just the specified voltage. The resulting load flow solution is appended to each of the busbars post-simulation. The four rows correspond to per-unit voltage, phase, active power, and reactive power respectively. Looking at Bus 1, it can be seen from the annotation that the swing generator delivers 76.4MW of active power and 27.5MVAr or reactive power to the network. Differences to the original benchmark are due to the transmission line models and transformer configurations used.

Model

Simulation Results from Simscape Logging

The plot below shows the dynamic response due to adding a 50MW load to Bus 6 half-way through the simulation. The additional active and reactive powers that the swing bus must deliver can be seen.