Study on Emergency Control Strategy for Transient Stability Based on Current Mutation Factor

Emergency control is an important approach to maintain security and stability of power system, and fast quantization of control strategy is significant for engineering calculations. This article is based on the engineering approach which is called ‘offline decision-making, real-time matching’. Firstly, the power-angle characteristic curve of critical cluster can be obtained by a time-domain simulation. Then, the current mutation factor around generator-shedding under the selected control strategy can be calculated through equivalent network, and the power-angle characteristic curve of critical cluster can be corrected by this factor. Finally, the stability of critical cluster will be determined by EEAC. The critical amount of generator-shedding can be found by increasing the amount of control constantly and cycling the above procedure repeatedly. Numerical examples shows that the accuracy of this method is good, and the sequence of all schemes will be sorted by the amount of generator-shedding meanwhile. So, this method can facility the search of optimal scheme and the exhaustive search in current project can be avoided.