Research on compensation start-up of self-oscillating resonant converter

Aiming at the complicated control problem of the existing inductively coupled power transfer system, a self-oscillating control method for the push-pull resonant converter with parallel-series compensation is proposed. The necessity of designing the start-up circuit is explained by illustrating the principle of self-oscillating control. Based on the analysis of the energy transfer mechanism of the start-up circuit, the method of injecting energy into the resonant tank to compensate the energy consumed by the resistance of the damped oscillation is obtained to solve the circuit start-up problem. A self-oscillating resonant converter experimental apparatus without the external controlling signal is designed and relevant parameters are tested, which shows the correctness of the start-up principle analysis and the simple reliability of the circuit designing.