Poles and Stability of a Feedback Control SystemSnapshot of the front panel of the simulator:
Description of the simulated systemIn this simulator a feedback system, namely a control system, is simulated. The controller is a P controller. The front panel of the simulator shows a block diagram of the control system. It can be shown that the transfer funcion from setpoint ymSP to process measurement ym is ym(s)/ymSP(s) = [H_{c}(s)H_{p}(s)]/[1 + H_{c}(s)H_{p}(s)] = K_{p}/(s^{3}+2s^{2} + s + K_{p}) = K_{p}/a(s) where a(s) is the characteristic polynomial. The stability property of the feedback system can be determined from the poles, which are the roots of the characteristic equation: a(s) = s^{3}+2s^{2} + s + K_{p} = 0 In the simulator the controller gain K_{p} can be adjusted in real time, and the response in the process measurement and the poles are shown. AimsThe aim of this simulator is to observe the connection between stability and pole placement. Tasks
Updated 17. January 2008. Developed by Finn Haugen. E-mail: finn@techteach.no. |