Research On Bidirectional DC-DC Converter For Electric Vehicle

At present,with the rapid development of the economy,family cars have become the most widely used means of transportation.However,the rapid increase in the number of cars followed by the rapid consumption of traditional energy sources and environmental pollution has become an urgent issue.With the rapid development of electric vehicles and gradually entering the lives of residents,in order to improve the overall performance of electric vehicles and the service life of batteries,two-way DC-DC converters are used in electric vehicles because of their advantages such as the ability to achieve bidirectional energy flow and reasonable use of energy.It becomes an indispensable module in the electrical system.In this paper,a combination of a battery and a super capacitor is used as the electrical system of the composite power supply module,a four-phase interleaved parallel DC-DC converter is selected as the topology,and the working state of the converter under different control methods is discussed.Firstly,This article introduces the main modules in the electrical system of an electric vehicle.It introduces common bidirectional DC-DC converters based on the design requirements on the system,divides them into two major categories based on whether there is electrical isolation,and discusses each topology.The advantages and disadvantages are compared and analyzed.Finally,a four-phase interleaved parallel topology is selected,and its working status is analyzed through different modes of intermittent buck-boost of the inductor,and the switch tube and main parameters are designed.In the control method,a double closed-loop control strategy of voltage outer loop and current inner loop is selected.Considering the shortcomings of traditional double closed loop in response speed,a fuzzy PI controller is designed to be introduced into the control system.Simulation through MATLAB/Simulink.After comparing with the traditional PI control strategy,the advantages of introducing fuzzy control strategy in double closed-loop control are verified.The dynamic response speed is faster and it is more suitable for working in bidirectional DC-DC converters.Working environment.