Identification of harmonic sources by a state estimation technique

A reverse power flow procedure is described to identify the sources of harmonic signals in electric power systems. Methods have been reported elsewhere to analyze the propagation of these harmonics signals throughout the network. Here the reverse problem of how to identify the source (and potentially the type) of harmonic signals is considered. Line and bus data at several points in the network are used with a least-squares estimator to calculate the injection spectrum at buses suspected of being harmonic sources. When energy at harmonic frequencies is found to be injected into the network at a bus, that bus is identified as a harmonic source