Controller design using the Bode plot

Abstract

We have learnt about the Bode plot representation and how easy it is to cascade simple process systems and modify the frequency response plot accordingly. We use this when we come to design with the Bode plot where we are going to cascade a controller with the system to give a satisfactory overall response. We present two design examples which look at introducing simple terms, such as gains and lag or lead terms, into the controller. Then we look at two controllers, called phase lag and phase lead controllers, which are specifically aimed at providing additional phase to the open-loop phase plot.