Performance Indices in Control System Design

As we already know that in control system design, output should approach the set or desired state. Such that error i.e. set point minus output equals zero.

During control system design process, one or more parameters are to be selected to give best performance. So a measure called Performance Indices are used for this purposes.

Performance Indices in terms of error e(t) are as follows

1. Integral of time and absolute error (ITAE)

2. Integral of time and squared error (ITSE)

3. Integral absolute error (IAE)

4. Integral squared error (ISE)

where,

e(t) = r(t) - c(t)