Research On The Design Method Of Loosely Coupled Wireless Power Transfer System Based On Multi-Factor Synthesis

With the continuous development of society and the advancement of science and technology,the power electronics and electronic information industries have flourished.Various types of electrical equipment have become more and more popular.It greatly enriches the daily life of human beings.In the widespread use of a large number of power electronic equipment,one of the issues that must be considered is the power supply problem.For traditional power supply methods,there are defects such as cumbersome wiring and fire hazards.Therefore,more reliable power supply and charging equipment has become an indispensable part of these electrical appliances.With the development of human beings,a new type of power transmission has emerged.The use of wireless power transfer technology can remove the constraint of the wire on the traditional power supply mode and overcome the inherent defects of the wire power supply.At present,the loosely coupled wireless power transfer technology has been recognized by the most scholars and technicians.It increases the transmission distance to the meter level and the power can reach the kilowatt level.loosely coupled wireless power transfer uses near-field non-radiative strong magnetic coupling.Theoretically,there is no harm to the human body.It can pass through non-metallic obstacles and has little effect on efficiency.Loosely coupled wireless power transfer technology is considered to be the most promising and most market-focused wireless transmission solution.It is especially suitable for large power transmission.However,due to the lack of universal design,control,and optimization methods,there are no finished products on the market.In previous studies,the main focus of the circuit design method was high efficiency,low voltage current rating,high control stability,and copper quality for low magnetic components.The magnetic flux density in the air gap has not been studied in the literature,even though it is the main indicator for verifying the safety of high power loosely coupled wireless power transfer systems.Therefore,there is a need for a new loosely coupled wireless power transmission circuit design method for low magnetic flux density,low voltage current rated coils,high control stability and low copper quality circuits.This study will develop a new loosely coupled wireless power transmission circuit design method that meets these requirements.In order to develop a loosely coupled wireless power transfer system design method based on multi-factor synthesis,a new feasible design space is proposed,using the coil voltage and current equation and its predetermined maximum allowable value.The number of turns and loop radius of the transmitter and receiver coils are varied until maximum power transfer efficiency and low flux density are achieved.In the entire feasible design space,not only the magnetic flux density and efficiency,but also the stability,coil voltage and current,coil voltage and current rating,required copper mass and operating frequency are controlled.Based on the calculated resonance performance,it is shown that no single point can simultaneously maximize all desired performance metrics.There are trade-offs between the design process.Therefore,the objective function is proposed as a design tool.The best design is determined by maximizing the objective function in the feasible design space.The relative importance of each item in the objective function is verified by calculating the parameter sensitivity of the objective function.Using weighting factors,the method enables the design of a new optimal loosely coupled wireless power transfer system that focuses on critical requirements.