Analysis And Optimization Of Anti Offset Performance Of IPT System Based On Least Square Method

With the development of modern science and technology,the market-oriented promotion,electronic and electrical products are more and more diversified,and the traditional contact charging mode can not fully meet the needs of users in different situations.Compared with traditional wired power transmission,inductive power transfer(IPT)has no direct electrical contact,no wear,no spark,no need for manual plug and pull,etc.,which is conducive to adapt to the harsh extreme environment,and has a wide application prospect in the fields of low power rate equipment,implanted medical equipment and electric vehicle of consumer electronics.In practice,the relative deviation between the original coil and the secondary coil in the IPT system is inevitable,which will lead to the change of magnetic coupling,which will lead to the instability of the electric energy transmission.In this paper,the wireless charging application of small power equipment is used as the background,and the above migration problem is studied to improve the coil offset resistance performance of IPT equipment.Firstly,starting from the generation of IPT technology,this paper introduces the development and research status of induction power transmission technology at home and abroad.The current research status and shortcomings of improving the anti offset performance of IPT system are introduced from the aspects of magnetic circuit mechanism,closed-loop control and compensation topology design.Based on the above introduction,the purpose and significance of this paper are expounded.Secondly,the basic principle of IPT system is introduced,and the energy efficiency characteristics of SS and SP compensation topology under full resonance compensation are analyzed.At the same time,the anti offset performance and economy of three basic coils,i.e.circular,square and DD,are analyzed.It is found that for small power system,the anti offset performance of circular coil under fixed line length is the best and the best economy.Thirdly,the output characteristics of the non fully resonant SS and SP compensated IPT system are analyzed.In order to better represent the resonance state of the original and secondary side,the concept of resonance factor is introduced.It is found that the anti offset performance of IPT system can be changed by adjusting the resonance factor parameters,which provides the basis for the parameter optimization.Then,the traditional evaluation methods and application defects of the anti offset performance of the IPT system are analyzed,and the least square method is proposed which is more suitable for the optimization of the IPT system.Combined with the IPT circuit model and performance index constraints,the parameters of the SS compensation and SP compensation IPTS are optimized by genetic algorithm,and the corresponding parameters optimization results are obtained.Finally,based on the optimization results,the system simulation platform of SS compensation and SP compensation is built.The simulation results show that compared with SS compensation,the original output voltage and current phase angle of SP compensated IPT system is larger and the output current amplitude is too large,which will cause great loss.So SS compensation is chosen as the compensation topology.In order to further verify the optimization results,a 50 W IPT system experimental platform is built.The experimental results show that the original and secondary coil is within 30% offset,and the optimized system output power fluctuation is lower than 15%of the rated power,far lower than the 180% power fluctuation of the system before optimization.So the output power stability of the optimized system is better than that of the traditional full resonance IPT system.The effectiveness of the proposed optimization method for the anti offset performance parameters of the IPT system is verified.