Research On Photovoltaic Charging Station Based On Three-Phase Boost-Derived Hybrid Converter

In recent years,global energy and environmental problems have become increasingly serious.To alleviate the severe energy crisis,the development of the new energy industry has received worldwide attention.With the maturity of new energy power generation technology and electric vehicle battery charge and discharge technology,the new energy vehicle market is experiencing a sharp increase trend.Countries around the world are actively conducting technical research and infrastructure construction for various types of charging stations.Traditional charging stations have expanded.In the field of renewable energy such as wind and light,the installed capacity of new energy units is constantly expanded.The new energy vehicle charging station represented by the photovoltaic charging station can enhance the utilization of renewable energy and has certain environmental significance.In this dissertation,a new type of single-input AC and DC hybrid output topology,three-phase hybrid boost converter?BDHC?,was combined with photovoltaic power generation system,three-phase AC grid and electric vehicle load to form a photovoltaic charging station system.The main modules of the photovoltaic charging station were analyzed in detail.Firstly,the principle of photovoltaic power generation and the mathematical model of photovoltaic cells are briefly introduced.The principles of common maximum power point tracking?MPPT?algorithms such as constant voltage method,disturbance observation method,conductance increment method and neural network method are introduced respectively.By improving the traditional conductance increment method,an incremental conductance MPPT algorithm?INC MPPT?is applied to the vector controller of the photovoltaic charging station to generate the through-duty D_st.Secondly,the structure,characteristics and working principle of the three-phase hybrid boost converter are introduced,and the steady-state analysis is carried out.According to the characteristics of the three-phase BDHC,a new pulse width modulation technique,Constant Frequency Shoot Through-Sine Pulse Width Modulation?CFST-SPWM?,is introduced and its simulation model was built.Then introduces the system model and control strategy of the photovoltaic charging station based on three-phase BDHC,and elaborates the three operating mode of the photovoltaic charging station respectively,which the maximum power point tracking,phase-locked loop and vector control in the photovoltaic charging station control were introduced.In the application of the system,based on the PQ model,a dual-loop control scheme for DC-side voltage control loop and reactive power control loop is established.,and the electric vehicle battery model and the common charging mode of the lithium battery are summarized,and the photovoltaic charging station is combined.The characteristics of the electric vehicle are charged by constant current and constant voltage charging.Finally,the performance of the modified INC MPPT algorithm,the performance of the DC voltage controller,the reactive power tracking performance,the stability of the controller in the event of grid failure,and the energy management performance during the charging process are verified by simulation and the vector controller shows good performance.Figure[70]Reference[61]Table[11].