Efficiency Analysis And Optimization Design Of Self-Oscillatory Push-Pull ICPT

Inductively coupled power transfer(ICPT)is a new power transmission technology by combination of power electronic,control and magnetic coupling techniques.ICPT system is a typical multi-parameters high-order nonlinear system.Parameters optimization design and transmission efficiency are the research hotspots of ICPT field.Therefore,the research of key parameters optimization design obtained by transmission efficiency analyzed is necessary.A start-up principle and control circuit for the sell-oscillatory push-pull ICPT system are proposed based on the analysis of the working principle and the energy transfer proc'ess during the start-up phase.The start-up control circuit is worked by injecting energy into the resonant network to com,pensating circuit loss and ensuring system oscillation.A driving control circuit is designed to realize the operating frequency automatic tracking with the oscillation frequency.It can improve the real-times response speed,stability of the system and avoid the system parameters disturb the transmission eff-iciency.Based on the mutual inductance and leakage inductance model theory,the system voltage gain,current gain and transmission efficiency expression are deduced.The influence of operating frequency,coupling coefficient and quality factor on the transmission efficiency of the system is analyzed by Matlab simulation,which provides the reference for the optimization of system parameters.A kind of non-core plane ring-shaped loose coupling tran,sformer is designed with the analyzed of the coupling coefficient,the coil winding method,the core shape,the transmis.sion distance and the shielding of the electromagnetic field.The critical condition of frequency bifurcation is obtained by analyzing the input impedance.In order to avoid the frequency bifurcation and achieve the maximum transmission efficiency as the goal,a self-oscillatory push-pull ICPT system parameters optimization design method is proposed.This design method can insure high-efficiency transmission by selecting parameters combination.The experimental results show that the theoretical analysis is correct and the feasibility of the optimized design method is verified.