High frequency alternating current power supply for automobile auxiliary electrical systems

This paper presents an HFAC power source concept for vehicle auxiliary electrical systems. The proposed power supply is based on a resonant DC to HFAC inverter, which constructs the output sinusoidal voltage and current. Mathematical modelling is employed to design the control strategy and Matlab Simulink is used to model and simulate the circuit operation under various load conditions. Simulation tests show that for the case of a 42V alternator plus rectifier as DC power source, the proposed system can supply up to 4kW in the form of one-phase 100Vrms, 50kHz sinusoidal voltage. Figures returned by the simulation place the efficiency of the zero-voltage switching inverter above 90% for most of the output range, with total harmonic distortion below 2%. Also, excellent performance of the HFAC power supply is proved based on fast response to step changes in output load.