An Impedance-Based Approach for Identifying Interharmonic Sources

This paper proposes a new method for identifying the interharmonic source location in power systems. The method is based on the interharmonic impedances measured at the metering points, and is inspired by the fact that the impedance of interharmonic-generating loads at that frequency is much higher than that of the utility system. This method represents an improvement over the traditional power-direction method, as the new method is more robust and less prone to erroneous identification. The issues associated with data reliability are addressed, and a set of data reliability criteria is presented. The effectiveness of the new method has been verified through simulation studies and field measurements.