Research Of Electric-field Coupled Wireless Power Transfer For Rotary Equipment

Wireless power transfer is a non-contact power transfer method which uses electromagnetic fields,electric fields,ultrasound as medium.The wireless power transfer can make the electric equipment get rid of the restraint of power lines,thereby obtaining greater freedom,so is widely used in production and life.Electric field coupled wireless power transfer is a non-contact power transfer method using alternating electric field as coupling medium.It is easy to implement and can avoid the disadvantage of eddy current generated by alternating electromagnetic field in electromagnetic wireless power transfer on metal surface,thus,it has unique application advantages in the metal environment.This paper is aimed at power transfer for the rotating parts of small rotary electromechanical equipment,with electric field coupled wireless power transfer.The main work includes:1.The power transfer system of electric field coupled wireless is designed,and the power control circuit of the transmitter is emphatically designed.The control circuit adopts a combination of PWM and H-bridge inverters:PWM adjusts input voltage according to power demand,and H-bridge inverters realize inverters to meet the requirements of power transmission.The control circuit is simulated in MATLAB,and the control performance is verified.2.The coupling characteristics of several commonly coupling mechanisms are compared.According to the characteristics of rotating electromechanical equipment and application,a double-ring coupling mechanism is designed.The optimal coupling relationship between coupling spacing and coupling capacitance of the coupling mechanism is simulated and optimized.3.The weak coupling situation caused by the limited coupling area of rotating electromechanical equipment,the compensation characteristics of CLC and LCL resonant compensation networks are compared and analyzed.The CLC compensation network is selected,and the circuit characteristics are analyzed according to the follow-up practical application.The relevant parameters are optimized and verified by simulation.4.An electric field coupled wireless power transfer system is built.The main control chip is TMS320F2182 and the H-bridge driver chip is IR2110.The function of power transmission system is tested,and the electric field coupling power transmission experiment is carried out.According to the specific application requirements,in the coupling mechanism with coupling area of 196cm2,coupling spacing of 5mm and coupling capacitance of 22pF,a CLC type compensation network is used,the power transmission system achieves 1.4W usable transmission with inversion frequency of 161 kHz and transmission efficiency of 31.8%.The design requirement of power transmission is preliminarily realized.The electric field coupled wireless power transfer system designed in this paper can provide electric energy to the sensing equipment installed on the rotating parts to meet their working needs.It is easy to implement and can work safely in metal environment.It is hopeful to overcome the monitoring problem of rotating parts of rotating equipment due to the difficulty of continuous power supply.