Research On Two-Stage Bidirectional AC/DC Converter Based On V2G

With the increasingly serious problems of energy exhaustion and environmental pollution all over the world,the sustainable development strategy of energy conservation,emission reduction and environmental protection has become more and more important.Due to its advantages of energy saving,environmental protection and great potential for development,electric vehicles have received worldwide attention and achieved rapid development in recent years.The popularity of electric vehicles and the status of a large number of electric vehicles connected to the grid,as well as the characteristics of electric vehicles with dual attributes of power supply and load,make the V2G(Vehicle-to-Grid)technology emerge as the times require and become a research hotspot in the cross-field of electric vehicles and power grids.The core idea of V2G technology is to use a large number of power batteries of electric vehicles as energy storage units to participate in the regulation of the power grid.By orderly charging and discharging of electric vehicles,peak shaving and valley filling and regulation of voltage and frequency of the power grid can be realized,and the operation of the power grid can be optimized.Bidirectional AC/DC converter is the core device to realize V2G function and the hardware interface to connect power grid and electric vehicle.It not only needs to realize bidirectional flow of energy,but also to control the power quality of input and output.It is of great significance to research high performance bidirectional AC/DC converter for the development of electric vehicle and V2G technologyChapter Ⅰ introduces the background,mainly including the development status and trend of electric vehicles and the concept of V2G technology,and then introduces the research status of bidirectional AC/DC convertersChapter Ⅱ gives theoretical analysis and simulation verification of two-stage bidirectional AC/DC converter,including the totem-pole bidirectional AC/DC converter and the CLLC bidirectional resonant DC/DC converter.The key parameters design and control strategy of two-stage circuit are also studied.Chapter III integrates the design of two-stage bidirectional AC/DC converter based on the theoretical analysis and simulation,and explains the key points and builds a 3kW experimental prototype.The main problems are the unification of control,the start-up of two-stage circuit and interference.Chapter IV presents the experimental results of two-stage bidirectional AC/DC converter,and the experimental results are explained.The theoretical analysis and design is verified by the experimental results.Chapter V summarizes the research work and prospects the future work.