考虑静止无功补偿器限幅特性的临界清除时间启发式算法

Heuristic algorithm for critical clearing time considering limiting characteristics of static var compensator

为克服静止无功补偿器(SVC)的限幅特性给电力系统暂态稳定分析带来的困难,本文基于短路引起的暂态过程中SVC导纳变化的特征,提出了1种故障临界清除时间(CCT)的启发式算法。计算故障轨线的投影轨线,并沿该轨线用容性导纳变化率确定CCT。由于不需要计算暂态能量、主导不稳定平衡点和故障后轨线等,因此该方法计算量小,暂态稳定分析效率高。对1个三机系统的算例分析结果表明,该方法得到的CCT相对误差小于10%。

To overcome the difficulty in power system transient stability analysis due to the limiting characteristics of the static var compensator(SVC),a heuristic algorithm is proposed to determine the critical clearing time(CCT) based on the features of SVC susceptance variation during the transients caused by short-circuit.The projection of the fault-on trajectory is calculated,and the CCT along it is determined by the derivative of the capacitive susceptance. The efficiency of transient stability analysis is improved because the transient energy,controlling unstable equilibrium point and the post-fault trajectory need not to be calculated. The analysis result of a three machine system shows that,the relative error of CCT is less than 10%.