A new PID controller design using differential operator for the integrating process

In the present study, a new control structure is proposed to control the integrating process. The proposed control structure is composed of both inner and outer controllers. The internal controller is integrated with the differ-ential operator to overcome the structural limitations of the PID controller to control the integrating process. The proposed internal feedback loop converts the integrating process into an open-loop stable process with a leaded phase. Moreover, it converts the process with higher ultimate frequency allowing the outer controller to be more strongly tuned. From the result of the simulation study, the proposed control structure guarantees better control performance than previous control methods. Furthermore, the control performance of the proposed method shows similar or better results than the previously proposed control methods (ITAE improved by 40.6% from the previous method in the water level control example).