Design Of Adaptive Backstepping Controller Based On Phase-shifting Full Bridge

With the development of agricultural modernization,whether high frequency switching power supply can meet the requirements of agricultural electrical equipment for input voltage has gradually become a research focus of relevant researchers.The stability of the switch power supply directly determines the efficiency and reliability of the equipment,it can meet the dc motor and other electric facilities for rapid and smooth regulating voltage required,try to reduce the power loss during the process of high frequency switch,inhibit excessive peak current and voltage fluctuation directly determines the stand or fall of switch power supply.In view of these requirements,this paper studies and designs a switching power converter for agricultural machinery,the main content is summarized as follows:Firstly,the background and significance of this topic are introduced,summarizes the current development of switch power supply and its control technology at home and abroad,and will be used in the topology of switch power supply circuit working principle has carried on the contrast analysis,finally put the phase shifting full bridge converter as the main circuit of high frequency switch power,at the same time,in a cycle of its working principle is analyzed,According to the design requirements,the parameters of the main components in the circuit structure are calculated and verified by open-loop simulation.Secondly,robust controller is designed for phase-shifting full-bridge converter.In the design process,dynamic surface backstepping control scheme with relatively simple structure is proposed based on dynamic surface control,and adaptive rate is designed to update system parameters in real time.Considering the unknown disturbance problem that may be encountered in actual production and life,the state observer is designed to estimate the unmeasured disturbance in the system,then the backstepping controller is designed,and the Lyapunov function is constructed to prove that the proposed control scheme has global stability.The proposed backstepping control scheme is simulated on the Matlab/Simulink experimental platform,and compared with other controllers.It is verified that the proposed backstepping controller has good robustness and dynamic response characteristics for output voltage control.Finally,an experimental prototype of phase shifted full bridge switching converter based on digital control chip TMS320F28034 is designed.It mainly includes the main power circuit design,control circuit design and digital control software design.Through the steadystate test,soft switching test and dynamic performance test,it shows that the controller scheme proposed in this paper can realize the stable control of the output voltage of phaseshifting full bridge switching power supply.