Study on contingency filtering and binary method tracing PV curves to voltage stability

A new fast approach to filter the critical contingencies and compute their PV curves is proposed for on-line voltage stability analysis. The expanded power model is applied and its solution is found by the optimal multiple method. The power flow equations of all the potential post-contingencies are solved at the load level associated with the minimum practically acceptable voltage stability margin, and the unsolvable cases are selected as the critical contingencies. At the base load level, the power flow equations of the selected cases are solved to determine the interval of post-contingency voltage collapse points. The PV curves of the selected cases can be traced by continuation binary method. The proposed approach is illustrated with the New-England 39-bus system and the IEEE118-bus system. The results show that the approach is very simple and efficient and is easy to be implemented.