基于录波曲线的电力系统低频振荡事故原因分析与抑制策略

如何快速确定电力系统低频振荡的原因并进行有效抑制，一直是一个备受关注的课题。提出基于录波曲线的电力系统低频振荡问题分析及抑制一体化新策略。首先，进行系统的特征值分析，根据系统是否存在与现场录波曲线振荡频率一致的振荡模式，判断系统发生的低频振荡属于强迫振荡还是弱阻尼振荡。然后，根据系统振荡的类型采用不同抑制策略，若系统振荡属于强迫振荡，进一步以探测排查的方式确定强迫振荡源的位置并消除振荡源，从而消除低频振荡；若系统振荡属于弱阻尼振荡，进一步通过阻尼转矩分析判断弱阻尼是由励磁系统还是调速系统引起，针对由励磁系统及调速系统引起的弱阻尼低频振荡，分别提出采用配置电力系统稳定器及优化调速系统参数进行振荡的抑制。方案的有效性和正确性通过实际系统的算例得到验证。

Cause Analysis and Suppression Strategy of Power System Low-Frequency Oscillation Based on Recording Curves

How to swiftly determine the cause of the power system low-frequency oscillation and suppress it effectively is always a subject of great concern. A novel integrated solution is proposed to analyze and suppress the power system low-frequency oscillation based on the recording curves. Firstly, the eigenvalues of the system are analyzed, and the type of the low-frequency oscillation is determined according to whether the system has an oscillation mode consistent with the recording curves. And then, different suppression strategies are adopted according to the type of the oscillation. If the oscillation is a forced one, detect the disturbance source, and eliminate it to suppress the oscillation. If it is caused by the poor damping, determine whether the poor damping is caused by excitation system or governor through analysis of the damping torque of the system. And a power system stabilizer and the optimized governor parameters are proposed respectively to solve the poor damping caused by the excitation system and the governor. The validity of the solution is verified by its application to an actual power system.