基于故障后最小动能轨迹的同步发电机暂态稳定性分析方法

Transient Stability Analysis Method of Synchronous Generator Based on Post-Fault Trajectories of Minimum Kinetic Energy

为了简单并准确地分析同步发电机暂态稳定性,提出结合时域仿真,并分别利用故障后系统稳定和不稳定时的故障切除时间和最小动能线性连接的交点,得到同步发电机的故障临界切除时间的混合评价方法。针对同步发电机模型不考虑阻尼和考虑阻尼2种情况,对提出的基于故障后最小动能轨迹暂态稳定性混合评价方法,分别进行了故障临界切除时间的计算,并和传统的故障后最小动能轨迹方法、时域仿真方法结果进行了比较。结果表明混合方法计算精度优于传统的故障后最小动能轨迹方法,该计算方法比时域法更简单。

In order to simply and accurately analyze the transient stability of synchronous generator （ SG）, combined the time domain simulation results, a hybrid evaluation method for critical clearing time （CCT） of SG is proposed according to the intersection of the two lines, which are the linear of fault clearing time and minimum kinetic energy after clearing fault when SG is stable or unstable, respectively. In the two cases of considering the SG models with damping and without damping, the CCT is calculated respectively by the hybrid evaluation method of transient stability, which is based on post- fault trajectories of the minimum kinetic energy, and the results are compared with the traditional post-fault trajectories method of minimum kinetic energy and the time domain simulation method. The comparison results show that the calculation accuracy of proposed hybrid method is better than the traditional post-fault trajectories method of minimum kinetic energy, and its calculation is simpler than the time domain simulation method.