Research On Control Strategy Based On LCC-S Magnetic Coupling Resonant DWPT System

At present,due to the increasingly prominent problems of global environmental pollution and resource shortage,electric vehicles have gradually received great attention from various countries as an effective way to alleviate this problem.However,problems such as low battery energy density indicators and long charging times have severely restricted the promotion of electric vehicles.Therefore,the magnetic coupling resonance dynamic wireless charging technology has become the focus of research.It can achieve real-time energy acquisition of electric vehicles during the movement,which greatly promotes the lightweight of the vehicle.However,since the dynamic wireless power supply system for vehicles is a complex nonlinear and strongly coupled system,in actual application conditions,the problem of mutual inductance fluctuations caused by external disturbances on the coupling mechanism cannot be avoided.At the same time,the dynamic changes of the load caused by vehicles entering or leaving will also aggravate the instability of the system.Therefore,based on the LCC-S magnetic coupling resonant wireless power transfer system,this paper proposes a bilateral control strategy that not only maintains the optimal efficiency,but also achieves power controllable power,so as to improve the stability of the system.First of all,the current research status of electric vehicle wireless power transfer technology at home and abroad is explained,and the existing control strategies are emphasized.On this basis,by analyzing and comparing the structural characteristics of different compensation topologies,the LCC-S topology is selected as the research object of this paper,and the mathematical model is constructed.Subsequently,the influence of the system operating frequency,mutual inductance,equivalent load and compensation inductance on its transmission characteristics was studied,which provided guidance for the selection of system parameters.Secondly,in view of the uncertainty of the mutual inductance parameters of the dynamic magnetic coupling mechanism,a mutual inductance parameter identification method based on the structure of the LCC-S magnetic coupling system is proposed.The weighted particle swarm optimization method is used as the identification algorithm for iterative optimization.Simulink is used to design a simulation model.After verifying the correctness of the identification model,the identification of mutual inductance parameters is realized.The simulation results prove the feasibility of the proposed identification method.Finally,around the power and efficiency fluctuations that exist during the operation of the dynamic wireless power supply system,comprehensively considering the system energy transmission characteristics,the respective voltage conduction angles are introduced into the inverter circuit and the semi-controlled rectifier circuit,and the mutual inductance is adjustable.Inside,by adjusting the degree of freedom of control on the transceiver side,the system's efficiency optimization and power stable output control are realized.Afterwards,the built simulation model is used for comparative analysis,and the results show that the system can maintain a constant voltage output when the system is controlled under different mutual inductances and to a certain extent can weaken the current distortion of the transceiver side.By building an experimental platform,the feasibility of the proposed bilateral control strategy is verified.