An Improved Method of Adaptive Under Voltage Load Shedding

The conventional under voltage load shedding method only based on the local voltage information, and the method designed without considerations on load characters and mutual influences of the voltage and the frequency, this method may cause the instability of power system. This paper puts forward an improved method of adaptive under voltage load shedding based on two rounds of action. The improved method has considered on influences of frequency and voltage dynamics on the load active power, then used real-time measured electric parameters to calculate the amounts of under voltage load curtailments. In order to ensure the accuracy of the action, the method added an accelerated round to prevent the voltage drops rapidly. Simulation results of IEEE 39-bus system has shown the superiority of new method in calculating the amounts of curtailments.