基于机组同调性的电力系统动态安全域改进解析法

大量仿真结果表明实用解析法求得的动态安全域(DSR)边界超平面系数的误差与机组同调性间有强相关性,据此提出基于机组同调性求解DSR的改进解析法.在实用解析法基础上将系统节点分为临界机组、剩余机组和负荷节点群,仅计算几个临界注入点,就可估算各组节点DSR边界超平面系数的修正量.IEEE 10机39节点系统和118节点系统的仿真结果最大误差分别小于4%和0.7%,计算时间分别为拟合法的7.5%和1.3%,表明所提方法速度快、误差小且合理可行.

An Improved Analytical Method for Determining Dynamic Security Region of Electrical Power Systems Based on Generator Coherency

The dynamic security region (DSR) can provide plenty of security information and have good prospect in application. The simulation approach determines DSR by a lot of numerical simulation work, while the analytical method is rapid but the error of the results is relatively high. Lots of observation show that the errors of DSR boundary hyper-plane coefficients determined through analytic method are correlative highly to generator coherency. A new improved analytical method based on generator coherency is presented. Based on the results of the analytical method, the system nodes are divided into critical generator nodes, remnants generator nodes and loads. By adding only a few new critical points the deflection of each group is solved. The improved analytical method reduces the errors obviously and preserves the speediness feature. The errors can also be controllable by adjusting the increased number of the critical points. Test results on the New England 10-generator 39-bus test system show that when the time taken is 7.5% of the simulation approach, the maximum error of the test points is less than 4%, while simulation on the New England 118-bus test system shows that when the time taken is about 1.3% of the simulation approach, the maximum error of the test points is less than 0.7%.