Analytical Model of Series-Connected 12-Pulse Rectifier with Constant-Voltage Load

This paper presents an analytical model of the series-connected 12-pulse rectifier with constant-voltage load. The operation modes of the series-connected 12-pulse rectifier is analyzed by using the switching function method, then analytical expressions of the input current, power factor and output current are derived. From the theoretical analysis and simulation results, some useful results are obtained, which are quite different from the parallel-connected 12-pulse rectifier. In a power supply cycle, the input voltage of the phase-shifting transformer contains 12 steps, the load current contains 12 pulses, and each diode of the bridge-rectifier conducts 150°.