Design of Compensators

Abstract

It is the intention of the control engineer to design a system which gives optimum performance. However, very often it happens that the specifications offered by different users vary, and therefore, it becomes necessary to do some adjustments either in the design of the system or insert some external devices to obtain the required performance. The control system design engineer has used his ingenuity to design the system or process to give optimum performance in general. Therefore, the given system has been altered as much as possible to meet the performance specifications of many users. Further alterations of the plant parameters may not give optimum performance in general. Now the option is to insert some devices according to the requirement of the individuals so that the already designed system together with the additional devices inserted gives optimum performance. These additional components or devices which are inserted into the system equalize or compensate the performance deficiency. These compensating devices may include electric mechanical, hydraulic or pneumatic components and they are called compensators. Thus, the process of adjustment or alteration of a control system to get the desired performance specification is called compensation. The additional components or circuits that are inserted into the system in order to compensate for a performance deficiency are called compensators. In this chapter, we discuss the design procedure for electric circuit compensators.