Abstract:

Traditional proportion-integral-derivative (PID) controllers are generally used in single-input-single-output (SISO) systems. It is very difficult to design a PID controller for a multiple-input-multiple-output (MIMO) system which has intensive interactions among input and output degree of freedoms. In this article, a new design is put forward for the application of PID controller to the vibration control of high-order flexible structures. A reduced-order model is obtained by curve fitting of the frequency response functions in a specified frequency range and the process model is created. The PID controller for vibration control of a MIMO system is then designed using the internal model control (IMC) method with Maclaurin series expansion. A four -tier rigid frame is used to simulate the PID controller design process, and the results show that the technique presented in the article for the design of the PID controller is effective in rejecting the adverse effects of the uncontrolled modes and controlling external disturbances. The vibration control results of the four -tier rigid frame are satisfactory.

Key words: vibration control, internal model control (IMC), PID, multiple-input-multiple-output (MIMO), reduced-order