一种捕捉失步中心位置的新方法

目前工程应用的失步解列装置基本是通过最小测量电压或最小测量视在阻抗幅值去捕捉失步中心的位置,然后判断装置是否实施解列,但仅通过电压幅值或反映电压幅值的视在阻抗幅值不能判断失步中心的位置方向。无功功率与电压存在强耦合的关系,通过u cosφ轨迹过零等方法可以判断出失步中心出现的时刻,此时瞬时无功功率在失步断面联络线上呈单调性分布且在失步中心处大小为0。基于此,提出了通过无功功率捕捉失步中心位置的算法。该算法在确定失步中心的位置范围的同时可判断出失步中心的位置方向,可给出更多的振荡信息。最后,通过仿真进行了必要的说明。

A New Method of Capturing the Out-of-step Central Location

The stepout devices capture out-of-step central location through minimal measured magnitude of voltage and apparent impedance in current engineering,and then decide whether to starting stepout.But the direction of out-of-step central location can't be judged only by the voltage magnitude or the magnitude of apparent impedance that reflected voltage magnitude.There's strong coupling between reactive power and voltage.The occurrence time of the out-of-step center can be determined through locus zero-crossing method and so on,and at that time instantaneous reactive power presents monotonic distribution and its value is zero on the connection lines of out-of-step interfaces.An algorithm of capturing out-of-step central location through reactive power was put forward.The algorithm can contemporarily determine the scope and direction of out-of-step central location,and supplies more oscillation information.At last,necessary explanations were given by simulations.