Research On Vehicle Charger For Electric Vehicle With PFC

In order to cope with the energy crisis and environmental pollution,electric vehicles have developed rapidly,and as an important part of electric vehicles,charging machines have become a hot topic of research in recent years.Charger into the car charger and car charger,rather than the position of the car charger is fixed,a charging stations within the quantity is limited,and the cost price is more higher shortcomings,will make the users convenience greatly reduced,so is very necessary to research a kind of flexible to carry car charger,anywhere for electric vehicle charging,it will also to promote the popularity of electric cars.First according to the domestic and foreign manufacturers of car charger technology parameters and industry standards,to make the design of this topic car charger basic parameters,the overall design scheme of car charger,eventually choose two levels of structure,the front stage is a power factor correction(PFC)system.its main circuit USES no bridge Boost PFC passive lossless soft switching circuit,control circuit controlled by single cycle;The back stage is DC-DC conversion system,and its main circuit adopts full-bridge LLC resonant conversion circuit.Then for the first level of PFC system,analyses the working principle of main circuit,the control loop uses a single-cycle control trailing edge modulation control in continuous conduction mode(CCM),and analyzes its stability and ability to resist disturbance,the design of the parameters of PFC main circuit components and components selection,including the calculation of maximum input power and current,the design of main circuit parameters,selection of power devices and the design of the passive lossless snubber circuit,the control circuit of PFC circuit design,including sampling circuit,voltage feedback circuit and reset integrator,etc.;For level DC-DC transform system,after analyzing the working principle of main circuit in different working area,the system modeling,studies its excitation inductance and resonant inductance ratio,as well as the quality factor of the three parameters on the influence of the gain characteristic of the converter,then the whole bridge LLC resonant conversion circuit design parameters,including the output capacitance of the MOSFET tube,vice side rectifier diode,resonant inductor and transformer parameters such as design,control circuit adopts digital PI control,and its hardware circuit and softwaredesign.Finally,a model of the front-stage PFC system and the back-stage DC-DC conversion system of the vehicle charger was built on the MATLAB/simulink platform.The front-stage part achieved a high power factor,with the power factor reaching 1 and the input current harmonic being low.In the latter part,the wide range of voltage regulation is realized,and the output voltage ripple is relatively small.The overall efficiency of the system is high,which verifies the effectiveness of the on-board charger designed in this topic.Figure [91] table [4] reference [58]...