Study On Fuzzy Sliding Mode Control And Common Model Control Applied In The Control System Of DC/DC Converter

After several decades of development, switching power supply has been widely applied in many fields such as Household appliances and Electronic equipment. With its advantages of reduced volume, weight, calorific power and improved efficiency, performance, switching power supply has been substituted for linear power supply gradually. DC/DC converter is the basis of modern high frequency switching power supply. Its control method has been research hotspots with the application of switching power supply expanding. Owing to switch, DC/DC converter is a kind of time-variant, nonlinear circuit. The traditional control method is based on the linear system theory by establishing the state-space average model. In recent years, many advanced control methods has been developed. Compared to traditional control method, they have especial advantages. In this article, the advanced control method will be used to improve control effect on the basis of traditional control strategy. The content are as follows:Firstly, according to the typical control strategy, the voltage mode and current mode control scheme are established on the basis of the state-space average model of Cuk converter, then based on the classical control theory, the design of controllers is accomplished and the criterion of stability is presented.Secondly, the fuzzy logic control scheme for DC/DC converter is built up. With the combination of fuzzy logic control and sliding mode control, the fuzzy sliding mode control is proposed to improve the robustness of system.Finally, the common model control of DC/DC converter is studied. The inverse model of the plant is identified by RBF neural network and embedded in the common model controller. In order to overcome the error of identification, adaptive control is integrated into common model control and the control effect is improved.