Research On Dynamic Wireless Power Supply Stability Control Strategy For Electric Vehicles

With the rapid development of the dynamic wireless supply technology of electric vehicles,especially when electric vehicles are in scale development,the technology not only makes the electric vehicles easy to charge,but also reduces the requirements for the battery capacity of electric vehicle.However,the dynamic wireless power supply system of electric vehicles has the following problems: the unreasonable design of transmitting coil track of the ground end and the different battery charge of each electric vehicle at the receiving end.Besides,the system has transmission power fluctuations,control instability and other shortcomings.This paper aims at the power stability of dynamic wireless power supply of electric vehicles and make the power supply of the system stable by optimizing the design and control of the transmitting coil.In this thesis,the research on power stability control strategy of dynamic wireless power supply for electric vehicles is analyzed as follows:Firstly,the structure of the dynamic wireless power supply system of electric vehicles is analyzed.And considering the practical application,the rectangular coil is selected as the transmitting and receiving coil.By comparing and analyzing the output characteristics of the dynamic wireless power supply system of electric vehicles with different compensation topologies,the suitable constant current/constant voltage switching topologies are selected.Secondly,considering the wide variation range of the load and to reduce the fluctuation of power during vehicle movement,according to the charging characteristics of lithium batteries and considering different vehicle battery conditions,a constant current/constant voltage wireless supply system and topology switching method are designed.Finally,for different dynamic power supply scenarios of electric vehicles,the dynamic supply mode of the segmented guideway is proposed,the riding position of detecting device is given and the control method of coil is designed.Overall,this paper aims at the electric quantity of batteries of electric vehicles,proposes a track design method for the fluctuation suppression of multistage electric vehicle dynamic power supply and a compound control strategy of constant current/constant voltage switching and power stability by using the principle of eliminating polarity by coupling between adjacent tracks.The mutual inductance fluctuation is controlled within the acceptable range of the system and the transmission power is relatively stable.Finally from the experiment,we can see the superiority and stability of the power stability control strategy.