Analysis And Control Of Voltage Stability Based On Power Flow Algorithms

The paper studied the application of different power flow algorithms on the analysis and control of voltage stability.In the aspect of voltage stability analysis, the focus is on the application of continuation power flow on static and dynamic voltage stability analysis, as well as the application of minimum power flow algorithms in case of voltage unstable contingencies. In the aspect of voltage control, the paper focus on the application of voltage stability index on contingency ranking and voltage weakness analysis, and the application of power minimization algorithm on the optimization of voltage control strategy.Taking advantage of continuation power flow algorithms, the paper employed a typical 3-node model to analyze the influence of load model selection on voltage stability, verifying the conclusion that voltage stability margin of dynamic load model is much less than that of static load model. Taking a practical voltage analysis and control case as an example, the paper studied the influence of load-increase direction on voltage analysis, drawing the conclusion that the value of voltage stability margin in predictive load-increase direction is closer to the true value, and the result in average load increase direction is better for voltage stability weakness analysis of network configuration. A sensitivity index of voltage stability is proposed for voltage weakness analysis, which is more effective in voltage weakness analysis compared with the result using voltage amplitude index. Still on, the paper analyzed the voltage stability for a voltage unstable contingency, compared with the result from transient voltage stability time-domain simulation method, showing that the transient simulation method is more suitable for fault voltage stability analysis.