State-space average-value model of 3-phase 4-wire diode-bridge rectifier

A 3-phase 4-wire diode-bridge rectifier is one solution of the front-end DC power for high power multilevel inverter. The average-value model (AVM) of 3-phase 4-wire diode-bridge rectifier under continuous conduction mode (CCM) within generator-rectifier system is presented based on state-space averaging method. The AVM is validated using the corresponding switching model of rectifier by simulations in the Matlab/Simulink environment, and using a hardware test system composed of a synchronous generator and its 3-phase 4-wire diode-bridge rectifier load. The results show that the AVM can captures the key steady-state and transient characteristics of the rectifier, and the agreement of DC voltage between the AVM, the switching model, and the hardware circuit are well. The model presented herein can be used for modeling, impedance mapping, and stability assessment with small disturbance of such generator (transformer) -rectifier systems.