The Research On Characteristics Of Contactless Power Transmission Converter

Inductively coupled power transmission system based on the electromagnetic coupling theory achieves contactless power transmission with security,convenience,flexibility and reliability.Power transmission efficiency and transmission distance have been limited seriously because ICPT system uses loosely coupled transformer and has low mutual coupling coefficient.So further development and application of contactless power transmission system have been restricted.On the basis of the previous studies,further theoretical and experimental studies have been developed aboat the shortages of unstable output voltage,small output power and low transmission efficiency.Firstly,various equivalent circuit models have been established and mutual inductance equivalent circuit model has been chosen to analyze the whole article because it is more accurate and more engineering.Secondly,various factors have been analyzed that affect the operating characteristic of overall system and have been considered to improve energy efficiency.Resonant capacitors of primary and secondary circuits have been designed under considering the primary and secondary winding resistance.Then,the circuit can achieves resonance.The feasibility of the parameter design has been verified by MATLAB simulation and experiment.Thirdly,Control scheme of ZCS soft-switching technology and energy injection control mothod have been analyzed and determined.So the ZCS soft-switching technology can be achieved and improves the transmission efficiency of the high-frequency inverter circuit.The output voltage can be regulated quickly by energy injection control mothod.All theories have been verified by simulation and experiment.Simultaneously,a kind of accurate calculation method about energy injection duty cycle has been proposed innovative using the energy conservation theorem.The calculation method also considers nonlinear of energy growth.Finally,output voltage,output power and transmission efficiency about series-to-series type and parallel-to-series type of ICPT system have been analyzed under considering primary and secondary winding resistance.Law of characteristic changing with the equivalent load resistance and coupling coefficient has been detailedly studied.And,optimized load resistance and optimized coupling coefficient have been deduced under maximum load voltage,maximum output power and maximum transmission efficiency.The operating characteristic of the system has been improved by theoretical study.Simulation and experiment verify the correctness of optimized parameters and compare the characteristics of two systems.For the shortages of the research on inductively coupled power transmission,more comprehensive and accurate theoretical analysis with wider application range has been proposed.The simulation of ZCS soft-switching and energy injection control mothod has been built.A small-scale experimental platform of ICPT system has been developed and has achieved real-time regulator,low power loss and high transmission efficiency.