基于功率及频率波动相位的强迫扰动源定位

摘要

In order to accurately and rapidly locate the forced disturbance-source of power system,an online monitoring and locating method based on the wide-area measurement system is proposed,which compares the phase-angle between the active power fluctuation and the voltage frequency fluctuation.If generator is the disturbance-source,the angular frequency fluctuation phase-angle is in advance of the power output fluctuation phase-angle and the angle difference is less than 90°.On this basis,the branches of network are analyzed according to the energy function and disturbance propagation.If the absolute phase-angle difference between the active power fluctuation of a branch and the voltage frequency fluctuation is less than 90°,then the oscillation energy flow of the branch and the active power flow have same direction,the disturbance-source of power system can then be located accordingly.The TLS-ESPRIT algorithm is adopted to directly obtain the phase-angle of fluctuation when the system is in steady state,the time when the oscillation enters the steady-state stage is not required,and the influence of transient components and abnormal data could be eliminated.Calculative results of case study verify the feasibility and validity of the proposed method.%为了实现电网强迫扰动源的准确快速定位,基于广域测量系统提出一种比较有功功率波动及电压频率波动之间的相位关系来实现扰动源在线监测定位的方法.如果扰动源位于发电机上,则发电机角频率的波动相位超前于输出电气功率的波动相位且相位差小于90..在此基础上,根据能量函数及扰动传播对网络中的支路进行分析,如果支路有功功率波动及电压频率波动的相位差的绝对值小于90°,则支路上振荡能量流向与有功方向一致,据此可实现电网扰动源的定位.采用TLS-ESPRIT算法能够直接获取系统稳态时的波动相位,无需判断振荡进入稳态阶段的时间点,且能够消除瞬态分量以及异常数据的影响.实际算例验证了所提方法的可行性及有效性.