Stability Control of Load Voltage Loop of Boost Circuit for Wireless Charging of Electric Vehicle Based on Active Disturbance Rejection

With the continuous deterioration of the environment, electric vehicles are widely used in daily life, so how to achieve the stable output of load voltage during wireless charging is the main problem of current research. In this paper, LCC-S(LCC-S resonance compensation topology) circuit is used as resonant topology to realize constant voltage output, ADRC(Active Disturbance Rejection Control) is used instead of PID to control the voltage closed loop to achieve better tracking signal and anti-disturbance. First, the H-bridge phase shift control in the inverter circuit is analyzed, then the full resonance condition and output characteristics of the LCC-S topology are analyzed, and then the overharmonic fluctuation range of the voltage under the two kinds of control is compared. Finally, the wireless charging circuit model based on LADRC(Linear Active Disturbance Rejection Control) is built in matlab and the output is verified. The perturbation is also added to show that ADRC has better advantages.

I. Introduction

In recent years, due to the increasing demand for wireless charging technology for on-board electric devices such as electric vehicles, the international research on this technology has increased. The application of wireless charging technology in electric vehicles can make the complete electrical insulation between the power supply and the electrical facilities, high safety, strong flexibility, and solve a series of problems caused by aging and wear of the plug, which has high practical value in real life [1]. In the wireless charging system, the high-frequency magnetic field generated by the contactless coupling coil replaces the traditional wire for power transmission, which makes the system easy to be interfered [2]. In order to reduce the output fluctuation and improve the output stability, it is necessary to improve the control strategy with faster response and higher anti-interference ability in the feedback.