ABSTRACT
This chapter addresses the question of how one chooses the controller parameters. Tuning of controllers can be viewed as either being stability driven or performance driven. While this gives one a framework to view the controller tuning concepts, it is clear that all controllers have to consider both stability and performance. For controller tuning based on stability, we will consider Ziegler-Nichols and other recent tuning rules. The most illuminating approach that can be classified as performance driven tuning is the direct synthesis approach. In the direct synthesis approach, the controller is directly related to a particular closed loop performance that the control engineers choose for their system. A direct extension of this idea leads to the IMC tuning rules. The direct synthesis approach will also be used to understand performance limiting components in open loop transfer functions.
