| With the rapid development of high-tech industries,the stability and reliability of the power supply aroused more and more people's attention.Non-isolated buck circuit(Buck)have been widely used in the aeras of electric vehicles,the large capacity uninterruptible power supply,communication systems,national defense and military facilities,as well as various electric apparatus?Traditional buck circuit adopts proportional integral(PI)control in order to realize Zero steady state error control for controlled variable,the parameter given by the traditonal PI controller is difficult to overcome the dynamic over shoot in the case of start or substantial disturbance,and it will cause damage to electrical equipment in severe cases,so the soft-start devices and other hardware devices have to implemented to suppress overshoot?The fuzzy control technology is introduced to buck circuit in the paper,and the corresponding fuzzy control rules are established based on the analysis of the traditional PI control.Obfuscation is implemented on the difference between the fixed variable and its feedback,and its results are used as the input of fuzzy controller.The output signal of fuzzy controller provide information of Duty cycle or the correction parameters of PI controller for the power switch in the buck circuit,thus the fuzzy and fuzzy PI controller of buck circuit can be realized.A buck circuit system based on fuzzy controller has been designed in this paper,and the specific work includes the following aspects:First of all,this paper introduces the application background and development situation of buck circuit and its control methods.Main content and research status of the fuzzy controller are also emphasized.Accordingly analyzes the significance of fuzzy control technology in the further study of buck circuit control field.The implemation of fuzzy control method in buck circuit field are also described.Secondly,based on the analysis of mathematical models,the principle work modes of buck circuit are deeply researched,discontinuous inductor current mode and continuous inductor current mode are analyzed respectively.Combined with practical application background,two kinds of control method of Buck circuit are described as a voltage source and a current source.Thirdly,the basic principle and application process of the fuzzy controller are studied.Pure fuzzy control technology and fuzzy PI control technology were respectively implementd to Buck circuit controller,and the effectiveness and feasibility are also analyzed.Finally,the parameters of the main circuit and driving circuit as well as sampling circuit are designed,and the working principle of the corresponding circuit is analyzed.The circuit structure and control algorithm of this circuit is validated by the Matlab/Simulink simulation software and real experimental prototype is realized.Experimental results show that the buck system with fuzzy PI controller meets the design requirements. |
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