Research on wireless charging system turn-off current control based on variable step size disturbance observation method

With the popularity of cars, Electric vehicles are widely used for people’s travel. The improvement of electric vehicle charging technology has been accompanied by the development of electric vehicles. This paper mainly aims at the realization of wireless charging soft switch to improve the wireless charging of electric vehicles. In this paper, the principle of static wireless charging system is analyzed, the working state of soft switch of primary side inverter is analyzed, and the condition of realizing soft switch is obtained. The curve of switching current value with frequency is obtained by MATLAB under the condition of coupling. On this basis, the variable step size disturbance observation method is proposed to control the inverter output turn-off current to realize the characteristics of soft switch and improve the inverter output voltage and current waveform. Finally, a 10kW static wireless charging simulation model is built in SIMULINK. And compared with the model without disturbance observation method, the adjustment of off current is realized, and the appropriate small off-current is found, therefore the soft switch is achieved.