Design Of Inductively Coupled Non-contact Power Transfer System Based On Loosely Coupled Transformer

Inductive coupling contactless power transmission system as a new power transmission method has a very broad application prospect.It has the characteristics of no friction,no electric spark,and can realize radio energy transmission in the state of relative motion.The transmission efficiency of the system itself is the focus of investigation,and the frequency is an important factor of the transmission efficiency of loosely coupled transformer.Meanwhile,the compensation and the design of each structure of the system are of great significance to the performance of the power transmission system.In this paper,the magnetic circuit analysis of a typical loosely coupled transformer is introduced.The simulation model of the axial loosely coupled transformer based on COMSOL is built.The calculation method of the transformer parameters is introduced.The simulation analysis of flux distribution and parameter changes are made when the relative positions of the primary and secondary sides are changed.In this paper,the structure and working principle of inductively coupled contactless power transmission system are analyzed firstly.The loose-coupled transformer is modeled and analyzed,and the leakage inductance and mutual inductance equivalent models of loose-coupled transformer are obtained.From this,the relationship between transmission efficiency and frequency of loose-coupled transformer is deduced.Based on the analysis of the relationship between the transmission efficiency,the related compensation topology structure,and physical fields in finite element analysis software COMSOL compared under different frequencies,the output power of compensation before and after compensation,and the contrast between the transmission efficiency and the frequency graph,the result of simulation shows that the loosely coupled transformer reached the maximum transmission efficiency will be at a high frequency.Secondly,based on the current generation of three kinds of high frequency,a high frequency power supply based on the principle of power amplification circuit and signal generator is selected and designed.The frequency and efficiency of the loosely coupled transformer with compensation is tested experimentally,and the corresponding optimal frequency is obtained.Then,the optimal frequency required for power transmission of loosely coupled transformer is designed by inverter circuit,and the high frequency module of the inductively coupled contactless power transmission system is obtained.Thirdly,the induction coupling contactless power transfer system dc power supply and voltage stabilizing circuit,rectifier filter circuit principle analysis,by protel mapping practical circuit,the formation of open loop system,after the relevant simulation model is set up in MATLAB,on his analysis incorporating feedback and different forms of open loop,feedback after constant current and constant voltage output.STM32 chip is applied to sample voltage,current and frequency of the system,so as to realize the feedback among the three,and form a feedback closed-loop control system..Finally,an experimental platform of inductive coupling contactless power transmission system is built and tested.The output performance of voltage stabilizing circuit,high-frequency module and system is tested experimentally to realize the experimental platform with output power of 1KW.Through closed-loop feedback control,the terminal voltage and current are constant to reach the voltage source and current source.It lays a good foundation for further research on inductive coupling contactless power transmission system.