ABSTRACT
This chapter describes the cascade and rate feedback controllers of the static and dynamic types. A static gain controller consists of placing an amplifier with static gain in cascade with the plant that affects the loop gain and hence the coefficients of the characteristic polynomial that determines the closed-loop system response. A dynamic controller is a dynamic system described by a transfer function that suitably conditions the error signal to generate the plant input signal, thus affecting the closed-loop system response. Traditionally, first-order dynamic controllers are categorized as phase-lead or phase-lag type. The proportional-integral-derivate (PID) controller is a general-purpose controller that combines the three basic modes of control, that is, the proportional (P), the derivative (D), and the integral (I) modes. PID controllers are popular in the industrial settings for process control applications. Often, the controller has to be tuned in response to changes in the process parameters.
