Research And Implement On Anti-misalignment Wireless Charging System For Motor-Driven Carrier

Compared with wired charging,wireless charging has been widely used because it is more convenient and safer.Since low and medium power applications,such as motor-driven carriers,unmanned aerial vehicles,electric bicycles,and inspection robots,are frequently used and consume power quickly,they often need to be recharged.Wireless charging technology can be used to charge by itself without manual plugging,just by placing it in the corresponding charging position.This method is faster,more convenient and safer than wired charging.However,pad misalignment can influence system parameters that can lead to increased losses as well as reduction in power throughput.In this paper,improving the anti-misalignment capability of low and medium power wireless charging systems is studied.Firstly,the application background and research actuality of wireless charging technology are introduced.The main problems and existing solutions in the current application of wireless charging technology are analyzed and summarized.Through analysis,it is found that the misalignment tolerance and energy transfer stability of the wireless charging system can be increased by combining magnetic coupling structure design with compensation circuits.Therefore,this paper mainly studies the improvement of the anti-misalignment capability of the wireless charging system by using the magnetic coupling structure and the topology compensation circuit.The main factors affecting the magnetic coupling resonance wireless energy transmission are obtained through the circuit theoretical analysis of the basic topology compensation structure.In addition,theoretical research and circuit simulation analysis on the hybrid topology compensation circuit are studied.Because of its anti-misalignment characteristics and suitable for multiple coil pad,this circuit is used as the topology compensation structure of the wireless charging system in this paper.Secondly,two magnetic coupling structures（Solenoid Quadrature-Solenoid Quadrature,SQ-SQ and Solenoid Quadrature-Bipolar Pad,SQ-BP）are designed to improve misalignment tolerance of the system.ANSYS MAXWELL electromagnetic field simulation software is used to simulate and analyze the two coupled structures.By observing the changes of magnetic field distribution and mutual inductance during the coil offset process,the anti-misalignment capability of the coupling structure is tested.A physical model is built,and the experimental results show that the proposed coupling structure has high misalignment tolerance,and can be applied to wireless charging of motor-driven carriers and unmanned aerial vehicles.Finally,according to the simulation circuit and the design of the two coupling structures,the experimental platforms with operating frequency of 100 k Hz and transmission power of 20 W and 50 W are built,respectively.The transmission power,efficiency and misalignment tolerance of the system are tested.The maximum transmission efficiency can reach 90%.The charging system is installed in a motordriven carrier for wireless charging,and its anti-misalignment capability is tested.The experimental results verify that the designed scheme can effectively improve the antimisalignment ability and stability of the wireless charging system.