Research And Design Of Charging-Discharging Device On Vehicle For V2G Applications

With the rapid development of electric vehicle and the great efforts gave to smart gridbuilding, the proposed of concept of V2G (Vehicle to Grid) bring a new way to make themcommon development. With the key equipment of the V2G applications, thecharging-discharging device for EV battery plays an important role in the energy transferbetween grid and electric vehicle. And what this paper to do is to research and design thesingle phase charging-discharging device on vehicle for V2G applications.In the first, the theory analysis of the V2G technology is done in this paper, include theinfluence on grid by mass electric vehicles charging and the battery on vehicle as a distributedresource giving benefits to the power grid. And then this paper study the model、keyequipments、feasibility of V2G applications.After the functions and target of charging-discharging device on vehicle was determined,this paper focused on the research and design of it. Chose the two stage bidirectional powerconverter main circuit topology, which is contain a full-bridge PWM AC-DC converter and aBuck-boost DC-DC converter. Based on the Analysis of the basal of the converter topology,the control strategy of the energy transfer between grid and electric vehicle with unite powerfactor rectifying and grid-connecting is designed. Propose an improvement type of controlstrategy of voltage and current dual-loop PI control.The software and hardware design is realized based on the main topology theory andcontrol strategy. The hardware design, include the design of the main circuit power devices,sampling circuit, control circuit and driver circuit. Based on TMS320F28335DSP chip, thesoftware control is designed, include the software control system framework, controlalgorithm, implements, etc. which focused on the software flow control, bidirectionaltransformation of control flow, phase-locked loop realize. Detail introduction of hardware andsoftware control system design and clear concept make the paper maneuverability.Based on the system design, modeling of the system by PSIM software to prove thecorrectness of the control algorithm and the parameters, guide the software designing and theexperiment debugging. An experimental verification system based on PE-EXPERT3platformis build, the result of the debug validated the effectiveness of the propose design.