Sudden occurrence of a large forced oscillation (FO) is a challenging problem for power system operators, especially when the forced oscillation is resonating with a natural system mode. Among the methods for oscillation source location, the energy flow method has shown promise for detecting the source of a natural oscillation as well as a forced oscillation. In this paper, we analyze the performance of the energy flow method in depth by evaluating the expressions of incremental energy in one period of the forced oscillation and by looking at a wide range of forced oscillation frequencies. We show that the energy flow based method can misidentify sources of forced oscillations. That is, the method may not be able to locate the true forced oscillation source as well as identify a non-source device to be the source. Examples are shown for systems with different damping levels of system modes and for different load composition types.

中文翻译：

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振荡源定位的能量流方法分析

对于电力系统操作员而言，突然出现大的强制振荡（FO）是一个具有挑战性的问题，尤其是当强制振荡与自然系统模式产生谐振时。在用于振荡源定位的方法中，能量流方法已显示出有望检测自然振荡源和强制振荡源的希望。在本文中，我们通过评估强迫振荡的一个周期中增量能量的表达式并查看广泛的强迫振荡频率来深入分析能量流方法的性能。我们表明，基于能量流的方法可能会误判强迫振荡的来源。即，该方法可能不能定位真正的强制振荡源以及不能识别非源设备作为源。