Controller Requirements

With the controller, you intervene in the behaviour of A. If, for example, you have a pure P system and would like a control error of e = 0, you need I behaviour in the controller. If you only need a little more gain than the system already has, you take a P controller. So the controller can intervene in the type of behaviour of A, and it can increase or reduce its intensity.

In previous chapters we have already discussed which behaviour of A leads to which behaviour of the controlled system. So we use a controller in such a way that we obtain the required behaviour of A. For this, we first need a list of requirements for the controlled system. From it we derive the requirements for the controller.

Requirements for controlled systems

The following requirements for controlled systems are usually derived from the application:

1. Size of the steady-state control error

2. Duration of the transient behaviour until the steady state is reached

3. Permissible amount of overshoot

In addition, there are requirements that must always be met. These include, for example, the stability of the control loop.