Comparison of the error-integral performance indexes in a GA-tuned PID controlling system of a PWR-type nuclear reactor point-kinetics model

摘要

The control of a nuclear power plant is important due to its nonlinear dynamics. An optimized proportional-integral-derivative (PID) controller is a popular tool to this end. PID is tuned by various methods, including a genetic algorithm (GA). The quality and speed of GA optimization depend on the objective function as the performance index. In this paper, integral of absolute error (IAE), integral of the square error (ISE), integral of time-absolute error (ITAE), and integral of time-square error (ITSE) objective functions are evaluated. The results comparison is done based on overshoot/undershoot and the number of function evaluations (NFE) criteria. The PID gains are tuned to control of a typical pressurized water reactor (PWR), based on the point-kinetics model. The results show the high control performance compared to an empirically tuned PID. Also, ISE and ITSE are better performance indexes than IAE and ITAE in steady-states as critical situations. Also, these performance indexes have signified a good robustness against dynamics parametric uncertainties compared to an empirically tuned PID in every power mode. This comparative approach provides a good idea for experts to choose an appropriate performance index.