Impedance characterization of a six-phase synchronous generator-rectifier system using average-value model

A parametric approach for developing a dynamic average-value model of a machine-rectifier system is presented. The method initially requires a detailed switched model from which the rectifier/DC-link dynamics are captured using numerical averaging. The method is applied to a 240 Hz 6-phase synchronous generator-rectifier system. This system exhibits several distinct modes of operation. The output impedance is extracted using the averaged model developed for one of the modes. The resulting model is compared against the detailed simulation and shown to be very accurate in the time- and in frequency-domains.