| In recent years,with the development of power switch technology,the volume of the power supply,expandability function,power density,data communication function has higher requirements,to promote the development of digital power supply,modularization and high frequency,switching power supply gradually replace the linear power supply.Phase-shift full bridge converter as a kind of switch power supply,has the characteristics of high energy output,energy loss is small,the traditional linear power supply and control scheme is difficult to meet the requirements of high precision power supply,the phase shifting full bridge converter is the core of the DC charging pile device,due to the energy crisis and environmental pollution,high power DC charging technology in the study of the phase shifting full bridge converter has important significance to how to realize the phase shifting full bridge DC\DC converter stable and efficient output,has become a mainstream one of hotspots in the field of DC charging.In this thesis,the phase-shifting full-bridge DC\DC topology module power supply is studied.Compared with the traditional proportional integral(PI)control scheme,the dynamic response time is long and the output ripple value is large.In this thesis,a control scheme combining Takagi-Sugeno-Kang(TSK)and Mamdani fuzzy control is proposed.On the basis of TSK and Mamdani control,a composite control strategy with TSK-M fuzzy control as the core is constructed.On the basis of ensuring the output accuracy and the steady-state error of the system,the proposed control strategy can theoretically improve the dynamic response time and reduce the ripple coefficient.Firstly,based on the advantages of digital control power supply,thesis introduces the development status of phase-shifting full-bridge converter DC/DC converter and the application of soft switch in detail.Then,based on the characteristics of the phase-shifted full-bridge converter,the working principle and key waveforms of the phase-shifted full-bridge converter are analyzed,and the specific formulas are given to provide a basis for calculating the parameters of components in the actual circuit.Secondly,based on the TSK-M fuzzy control algorithm,the topology of phase-shifting full bridge is modeled.On the basis of the derivation and analysis of TSK-M algorithm,the closed-loop control system of phase-shifting full bridge DC/DC converter is completed by using the Simulink module in MATLAB simulation software.After that,the digital control platform with DSP chip as the core was built,the power peripheral parameters were configured,the intelligent control algorithm of digital power was designed,the power state program of power control was written,and the functions of phase-shifting control,TSK-M fuzzy control,circuit soft start,over-current voltage protection,and closed-loop control were realized.Finally,the correctness of parameter calculation and design is verified through simulation,and the simulation system of the converter is built and a physical prototype is made to verify the effectiveness of the proposed scheme.Simulation and experimental results show that the design results and simulation results match,meet the design index,with engineering practice,this article is based on TSK and Mamdani control,complement each other,building to a TSK-M compound control strategy of fuzzy control as the core in the output precision,the system steady-state error,on the basis of the proposed intelligent control strategy compared with traditional control scheme can improve 66% dynamic response time,maximum ripple coefficient decreases by 40%,the phase shifting full bridge converter performance improvements have guiding significance. |
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