Research And Application On Siso Digital Control System

Because of the mighty computing and logically analyzing function of computers, digital controllers have become one of the main ways in the realization of automotive control system. This paper put two kinds of process as objectives and does research on the discrete-time design method for SISO system. The purpose is to promote the speed of application for digital control theory. The two different processes are respectively: reverse process with time delay, tracking servo of DVD system.As for the reverse process with time delay, it is hard to achieve satisfied control performance, since there exists both reverse direction process and time delay within the original process. By now most results are in the continuous area, while seldom are in the discrete-time area. This paper designs a discrete time algorithm for the reverse time delay process using the direct design method in computer controlling. As for the DVD tracking system, the plant is a stable 2nd order process, and the major problem is ran-out phenomenon. In the second part of this paper, the current DVD standard speculation is analyzed and its limit is pointed out. The internal model control principal is applied to solve this problem and finally get a better result.Specifically, the main achievement of this research is as follows:1) The ringing problem of the reverse process is analyzed. The ringing problem is an important concern when the direct design method is conducted, because it results in big skips of controller output. The analysis by past researchers on ringing problem is only limited within first-order and second-order processes. This paper concludes that the true reason of ringing problem is that there exist poles near -1 of the controller output function u(z). The two conclusions for reverse process are: (i) For the second order reverse process systems, there is definitely no ringing; (ii) for the third order or...