Characterization of Residential Circuit Impedance

Electrical harmonics associated with switching power electronics have been observed to induce electromagnetic interference with equipment sharing the same electrical circuit. Some research studies have documented malfunction cases and even damage to particularly sensitive equipment due to this interference. The harmonic spectra of commonly used switching power electronics in a residential electrical system have been profiled before; this paper provides a phenomenological characterization of the voltage and current transfer function (in the frequency range 20 Hz - 100 kHz) from purported sources of electrical harmonics to the point at which a utility meter is typically installed (also the PCC to the service transformer). This work also evaluates the impact of shunt capacitance close to the point of coupling, resulting in a complex zero in the transfer function and the consequent impact on phase margins of the system.