The Research On Digital Control For DC/DC Converter Based On DSP

With the development of information society, electro-equipments have more requirements for high quality power. Due to its special advantages, digital control becomes a new research direction in power supply. In this paper, some research on the digital control in power electronics are accomplished, such as the influence of sampling holding and delay, digital control strategy, parameter setting and other main questions which exist in digital controlling system.The research on digital control focuses the DC/DC converter. Firstly, the DC/DC converter mathematics model is discussed and the average method of state space is used to set up the DC/DC converter's small signal model, and the system stability and the design of digital controller are mainly discussed. The theoretical analysis shows that zero-order holding process and sampling calculate delay will cause the decrease of stability of system, and the related quantitative analysis are introduced.Traditional PID control strategy still plays an important role in the application of digital control of converter, and the combination of advanced control arithmetic with traditional control will achieve more and more attention in the future. The parameter of traditional PID controller is derived by pole configuration. Based on it, such improved PID control strategies as integral abruption PID, incompletion differential coefficient PID and dead-time PID are analyzed. Furthermore the research has carried out for parameter adaptive PID. At last the experimental verification has been made on the prototype.