Fuzzy PI Control and Optimization of Startup Process of High- Speed DC Centrifugal Pumps

Background: Centrifugal pumps are key equipment used for fluid transfer in the chemical industry. During the start-up process of high-speed centrifugal pumps, the hydraulic characteristics such as flow rate and head will change significantly, and the optimization of the pump start-up process can improve its stability and service life, which will make centrifugal pumps more efficient in chemical production. Objective: Achieving a fast and stable startup process has always been a goal in the engineering application of high-speed centrifugal pumps. Methods: First, the mathematical relationship between the torque and speed of the centrifugal pump is established. Then, based on the physical characteristics of the DC motor and considering the centrifugal pump torque as the load, a mathematical model of the highspeed DC centrifugal pump is developed. A fuzzy PI controller for the high-speed DC centrifugal pump is designed by integrating traditional PI control methods with fuzzy control theory to manage the startup process. Optimization algorithms are employed to optimize the parameters of the fuzzy PI controller. Results: Before optimization, the settling time was 0.33 s, the motor speed overshoot was 7.69%, the head overshoot was 3.77%, and the flow rate overshoot was 7.69%. After optimization, the settling time improved to 0.25 s, the motor speed overshoot was reduced to 6.3%, the head overshoot to 3.1%, and the flow rate overshoot to 6.3%. Conclusion: A comparison of simulation results before and after parameter optimization demonstrates that the optimized fuzzy PI control yields better dynamic performance during the startup process of the high-speed DC centrifugal pump.