Measurement of harmonic sources in three-wire single-phase supply systems

Residential and commercial customers are usually supplied through single-phase transformers. The low voltage side of the transformer is a three-wire circuit with two phases and a neutral. This paper presents a measurement method that can determine the harmonic sources and impedances for this type of supply systems. The effectiveness of the proposed method has been demonstrated through simulation studies and field tests. A potential application of the method is to determine the harmonic contributions of the supply system and its customers at the utility-customer interface points.