Average modeling of diesel auxiliary power unit for series hybrid electric vehicle

A systematic physical model of diesel APU for vehicle applications is presented. The modeling approach uses the averaging techniques to account for the switching characteristics and nonlinear phenomena of three phase diode rectifiers, while preserves all the relevant dynamics of the diesel engine and synchronous generator. The subsystem models are interconnected in an elegant way and the over system model is obtained in the dq reference frame as an entirely physical one. Comparison with a detailed switching model validates the proposed average model.