抄録
Traditional control system with fixed gains may encounter problems such as large overshoot and large settling time. Large overshoot of the control rod position shortens the lifetime of control rod. Thus, improvements on traditional control system performance to decrease overshoot is necessary. A small pressurized water reactor model with a thermal power of 150MW is established by RELAP5. The model includes reactor core, pressurizer, two U-tube steam generators (SG) and main coolant pumps. Based on PID method, the reactor power control system, pressurizer pressure and level control system, and feedwater flow control system are designed. The parameters of the control system are tuned. The performance of control systems are tested by introducing step and ramp changes in load. The overshoot and settling time are evaluated. Due to large overshoot of control rod, fuzzy controller is adopted to improve performance of control systems. Through the introduction of typical load patterns, the performance of the optimized control system is compared with the traditional control system. Overshoot and settling time of the control rod position are decreased. Performance has been significantly improved by introducing fuzzy control.
