Optimization And Design Of Magnetic Coupled Structures For High Power Dynamic Wireless Charging System

Dynamic wireless power transfer technology can charge it during the driving of electric vehicles.When the battery energy storage technology is difficult to achieve breakthroughs in the short term,dynamic wireless power transfer technology can effectively improve the recharge mileage of the electric vehicle.The coupler is the main component of the wireless power transfer system,which has great effects on the power and efficiency characteristics,electromagnetic field exposure,and misalignment tolerance of the wireless power transfer system,which are also the main factor constraints of dynamic wireless power transfer technology development.In response to the above problems,this thesis is designed with a dynamic wireless power transfer system,and the design optimization method of the LCC-LCC resonance compensation network and the coupler is intensively studied.The specific work content is as follows:According to the characteristics of a high-power dynamic wireless power transfer system,four requirements are put forward for the magnetic coupling structure of the system,including space constraint,misalignment tolerance,electromagnetic shielding performance,and power and efficiency characteristics.The external circuit of the wireless power transfer system is analyzed and designed,including high-frequency inverter circuit,rectifier circuit,DC/DC conversion circuit.The circuit and magnetic circuit model of the DD coil are established.The working principle of the LCC-LCC resonant compensation network is analyzed,the influence of self-coupling between transmitting coils is analyzed,and the mathematical model in its non-ideal state is established.The influence of the parameters of the resonance compensation network and the magnetic coupling coil on the power and efficiency is analyzed,and the influence of the coupler on the resonance compensation network is expounded.On this basis,to reduce the voltage/current stress of system compensation elements,improve the power and efficiency characteristics and the misalignment tolerance,a design method optimizing bilateral LCC resonance compensation parameters is proposed following optimal efficiency,which implements the superior power and efficiency characteristics and the misalignment tolerance.A structural design and optimization method for magnetic coupling coil is proposed.Under the condition of meeting the transmission power and space constraints of the system,taking into account the static and dynamic performance of the system,and taking the shielding,misalignment tolerance,coupling performance,core consumption,and core loss of the magnetic core structure as the reference standard,the key parameters such as the length-width ratio of the coil and the size of two different magnetic core structures are designed.For the dynamic wireless charging system,considering the self-coupling of the energy transmitting coil and the output power pulsation of the system,the placement spacing of the energy transmitting coil is designed.The correctness and effectiveness of the parameter design of resonance compensation network and the design optimization of magnetic coupling coil is verified by simulation and experiments,the static and dynamic simulation models of the system are built in PLECS to verify the correctness of the analysis of the transmission power and efficiency of the system,and the superiority of the optimized magnetic coupling coil.A wireless power transfer system with a vertical transmission distance of 200 mm is built,and static and dynamic experiments are carried out to verify the correctness of simulation and theoretical analysis.Finally,14 kw power transmission is realized under the efficiency of 95.84%.