Research Of Decoupling Control System In Engineering

Decoupling is a study which has deep application. It has been studied for twenty years and it has become one of the popular directions in the domain of automatic control. It is widely applied in steelmaking, petroleum industry, chemical industry, light industry, mechanics and war industry. It is well known that industrial proceeding is viewed as orderly and interactive process. One fluctuated variable may touch other variables. Coupling is a widespread phenomenon in industrial proceeding. Variables interact each other, giving rise to the degraded property of adjusted system. We call this progress decoupling which curtails or eliminates the obnoxious interacting.An popular notion of decoupling degree for analysis and judgement is given in this paper. It is based on the investigation of the predecessor, such as Bristol's relative amplifying method which assessed the coupling degree according to the value of that departed from 1. But when the value was negative, the interacting extent was more serious than the value which was consumedly bigger than 1. Contrast to this, the which is advanced in this paper really shows the coupling degree. The triangle decoupling networks or the grouped networks are used to dilute the coupling degree. The simulating experiments prove the notable effect.In the procedure of grouped decoupling, the most serious spur track is departed from the system. The decoupling degree is reduced and is always greatly reduced in each departure. When the coupling degree is reduced to certain extent, the system can be stable. Then adjust the controller to make the output optimized. This is the core of decoupling degree. But in the process of lessening the decoupling degree, the ranks of equivalent controlled channels will be augmented. Thus, the reduced model is exploited in decoupling process in order to resume the plant prosperity which are distorded. It has greatly lessen the difficulty in group decoupling. Therefore, it is practical and applicable in engineering.The strongpoint of using transfer function to describe the systematic characteristic is simple, the defect is that it can't illuminate the whole character of the controlled system and its information is not integrated, while using state feedback is opposite. State feedback greatly suit pole placement. Getting optimized eigenvalue of det[sI-(A-BK)] = 0 is the target of pole placement by selecting state feedback matrix K. The root of state feedback can be placed in term of the form of Butterworth filter or Bessel filter. The condition of state feedback is that B is no-singular matrix. The so-called inner weakly coupled system can not be decoupled directly by employing state feedback. Exploiting the equation I= P-] (S)P(S), some scholars restructed the close transfer matrix to make det B 0. I advance the method. Instead of adopting exterior matrix P(S) diagonal 1 or s, triangle 0 or as which the predecessors used, I employ the exterior matrix P(S) diagonal 1 or the structure of IIR filter (for convenience, s+ is employed),triangle 0 or the structure of IIR filter(for convenience, a(s + p) is employed).This method eliminate the element 1/s in close transfer matrix whereas the predecessors's method carried. Employing this method, the output of the system is stable while the output of the predecessors's method isunstable. Simulation shows the effect of the ameliorated method.An imprecise model decoupling is studied. There are vast cases of imprecise or uncertain model in practical control engineering. Three aspects of creativity which have significance in decoupling system are studied. (1) employing the DMC method in predictive decoupling control system. (2)employing wavelet in decoupling process (3) The wavelet transform technique is employed in the diagnose of failure in decoupling control system and it get ideal effect.In the investigation of the decoupling fields, some decoupling methods which have its own feature are studied such as pseudo-forward-feed decoupling, etc. Forward-feed decoupling design is widely used in 2...