Research On High-voltage Capacitive Load Charging Technology Based On ICPT Principle

The use of electrical energy has greatly promoted social development.The relationship between human life and electrical equipment has become more and more close.Almost all electrical equipment is used to obtain electrical energy through cable connections.However,for mobile electrical equipment such as mechanical rotating equipment,rail transportation equipment,and mobile household appliances,this type of wired power supply seriously affects the flexibility of the equipment;for military,mine,underwater and other special environments,this kind of wired There are great security risks in power supply.When the equipment is in a natural environment,external lightning strikes and other abnormal energy will be supplied through the cable,resulting in equipment damage or abnonnal work,reducing the safe operation of the device,and the wireless charging method eliminates the electrical connector and solves the problem due to the cable.Many problems brought about by the connection,with high security,reliability and flexibility.This paper proposes a high-voltage capacitive load charging method based on the principle of ICPT,which can not only realize the wireless transmission of power,but also enhance its safety and flexibility,and achieve high voltage gain.Firstly,the basic principle and system structure of the inductively coupled wireless power transmission system are studied.The mutual coupling model of the loosely coupled transformer is analyzed.The reasons for the resonant compensation of the coupling transformer and the single-stage and parallel resonant compensation topology are introduced.This article's high-frequency inverter circuit and rectifier filter circuit,a high-voltage capacitive load charging system based on a series-parallel(SP)resonant compensation topology is proposed..Then the voltage gain and transmission characteristics of the four resonant compensation topologies are analyzed based on the mutual inductance coupling model,and the series and parallel(SP)resonant compensation topology suitable for this paper is determined,and the equivalent load impedance of the voltage doubler rectifier circuit is analyzed.When the size of the primary and secondary resonant compensation capacitors is changed,the relationship between the load voltage and the change of the working distance is analyzed.Then the system voltage regulation control strategy is analyzed,and a variable frequency phase shift control strategy is proposed.The load voltage transfer characteristics of the system with phase shift control strategy are analyzed.Finally,an experimental platform for high-voltage capacitive load charging system based on the ICPT principle was built.The voltage gain and primary current transmission characteristics of the system were verified by experiments.The experimental results are consistent with the theoretical analysis,verifying the application of inductively coupled wireless energy transmission technology.The feasibility of high-voltage charging,when the resonant frequency is 175kHz,the input voltage is 20V,the system primary current is less than 1A,can achieve about 3250V load voltage output,and can be stable in the range of 0-23.5mm gap distance,by adjusting the operating frequency The load voltage.