The Liquid Level Control Based on New Two-Degree-of-Freedom IMC-PID

For the cascade control system of double water tanks liquid level ,the water tanks model is established .The new two-degree-of-freedom IMC-PID regulator is designed by new internal model control(IMC) theory and it is the main controller of the cascade control system . The system performance is directly related to the two adjustable parameters of regulator. By adjusting the two parameters, very good dynamic response performance of both the setting value tracking and anti-interference characteristics can be achieved simultaneously. Simulation results have shown the validity of the proposed control scheme compared with the conventional PID regulator and the old two-degree-of-freedom IMC-PID regulator.