Elementary and ideal equivalent circuit model of the 1, 2/50-8/20 μs combination wave generator

The values of the parameters of the equivalent circuit model of the combination wave (surge) generator, which appears in the standard IEC 61000-4-5, are here derived so that open-circuit voltage and short-circuit current exactly meet the standard waveform requirements in terms of peak amplitude, front-time and duration. The time-domain expressions of the voltage and current waveforms are obtained in closed-form. The new verification procedure set in the draft edition 3 of the standard, that involves the use of an 18 μF capacitor, is discussed, and the aspects relevant to the design of the generator are analyzed.