Design And Implementation Of Fuzzy Controller For DC-DC Converter Based On DSP

With the development of information technology, switching power supply has been widely used because of its small body and high efficiency. At the same time, the requirements for the switching power supply is more and more strict, which are beyond the capabilities of traditional modeling and control methods. Moreover, the limitations of the switching supply power control realization with analog circuits become more and more evident. As a result, the simple, reliable, highly effective digital control strategies have been the direction of the switch power supply development.In this paper, the selection of the main parameters and basic topologies of DC-DC converters is first studied, the traditional modeling ways and current study situations of DC-DC converters used in switching power supplies are discussed. The research status quo of control strategy and control technology of DC-DC converters is reviewed and summarized.Furthermore, the PLECS models of Buck converter and Boost converter are built under MATLAB/Simulink environment in this paper. For the control object to Boost converter, the double closed-loop current control structure is adopted. The outer voltage loop is constituted by a fuzzy controller and an integral module, and the inner current loop is a PI controller. The output is the duty factor of the impulse signal for the switch component. In addition, T-S fuzzy controller has been designed for the buck converter. The simulations with fuzzy controller and PI controller are carried out separately and the simulation results show that the fuzzy control strategy can improve the dynamic performances of DC-DC converter also with static property.Finally, a small type digital control experiment platform is designed for the buck converter. The controller is designed using digital signal processor TMS320LF240 manufactured by TI company. On this platform, the experiment is taken using fuzzy control strategy, the results show the feasibility and validity of the control algorithm, and the designed systerm has high reliability and good dynamic and static performances with a simple structure.