Research And Design Of Frequency Controllable RF Power Supply For WPT

Since the introduction of wireless power transmission technology at the end of the nineteenth century,after more than 100 years of research and development,the technology has been more and more widely used in our lives.As the best energy transmission solution to overcome the constraints of wires,wireless power transmission technology has been widely used in many fields such as vehicles,smart homes,consumer electronics,and implanted medical devices.Connections based on wireless power transmission technique does not require wires.and the working characteristics of high isolation between the energy transmitting end and the receiving end can be achieved.In view of the increasing number of high-voltage side devices in the development process of smart grid,and its requirements for electrical energy stability,potential isolation and insulation strength.Realizing the power supply of high-voltage side equipment through wireless power transmission has become a solution with excellent development prospects.Aiming at the power supply problem of the high-voltage side equipment of the smart grid,this paper summarizes the currently applied or proposed high-voltage side equipment power supply scheme,and proposes the use of wireless energy transmission scheme to achieve the high-voltage side equipment power supply.After that,the resonance frequency and load impedance changes involved in the power supply process of the magnetic coupling resonance wireless power transmission system applied to the high-voltage side equipment were analyzed.In order to solve the problem of frequency and impedance,a frequency-controllable RF power supply with impedance tracking function for a wireless power transmission system is proposed.The specific work contents are as follows.First of all,the power supply design goals are clarified based on the background of the subject.According to the design goals,a radio frequency power supply implementation scheme based on frequency controllable signal source,power amplifier circuit,dynamic impedance matching network,impedance measurement device and control system was selected.After that,we conduct the structure and device selection of each module of the RF power supply and complete the circuit design and parameter calculation.Secondly,we use the Advanced Design System simulation software to simulate the power amplifier and impedance detection device of the RF power supply,verify the feasibility of the design scheme,and optimize its parameters.And the design of dynamic impedance matching network is simulated and optimized by HFSS simulation software.And we analyzed and designed the control system of the RF power supply.Finally,according to the design plan and optimization results of each module of the RF power supply,each module of the power supply was fabricated and parameter tested,and the power supply prototype was assembled.After that,an experimental platform for prototype testing was built,and the standard test of 13.56 MHz,50? load and variable operating frequency and variable load impedance test were carried out on the prototype respectively.The experimental results show that under standard test conditions,the RF power supply can maintain more than 80% of the additional power efficiency under the condition that the output power is greater than 50 W.Under the condition of variable operating frequency and load resistance,the RF power supply can achieve a relatively stable power output within the entire design range,and its power additional efficiency can be maintained above 75%.