利用局部量进行多机系统失步快速预测原理的探讨

本文研究多机电力系统遭受大扰动后系统首次摇摆暂态不稳定性的在线实时预测方法.导出了使用局部状态量的多机系统失步快速预测判椐及一系列计算公式,给出了失步预测与控制系统的初步构成方案.经多种故障条件下模拟计算,结果表明失步预测装置给出的稳定边界与使用全部状态量离线计算所得稳定边界相当吻合.

PRINCIPLE OF PREDICTING TRANSIENT INSTABILITY BY USING LOCAL VARIABLES IN MULTIMACHINE POWER SYSTEM

In a multimachine system,based on the direct method of Lyapunov,the criterion of prediction transient instability by using local variables is found. The total system imbalance power during fault may be calculated from the imba-lance power of arbitrary generator.So the transient energy that associated with the separation of the generator from the rest of the system can be calculated by measuring the local variables.The proposed scheme of high speed prediction for out-of-step consists of a computer in the control centre and microprocessors in power stations.A number of numerical simulations under different swing con-ditions show that the scheme is satisfied with both correctness and fastness.The fault critical clearing time predicted by the scheme is almost equal to that calculated by the numerical integration program under the same fault conditions.