A fuzzy, metrology-sound approach for the identification of the sources injecting periodic disturbances in electric networks

The identification of the sources injecting periodic disturbances in the electric systems is a critical point in the assessment of the electric Power Quality. The available methods, based on a deterministic approach, do not always provide correct results. Methods based on heuristic approaches, such as those based on a Fuzzy Inference System, provide better results, but do not allow measurement uncertainty to be evaluated in a straightforward way. This paper applies a modified Fuzzy Inference System to the identification of the sources producing periodic distortion in power systems. The method associates an index, provided together with its measurement uncertainty, to each load connected to a Point of Common Coupling, capable of assessing whether the load is injecting or suffering distortion and quantifying the severity of the injected or suffered distortion.