The Application Of Improved Auto Disturbance Rejection Control In The Thermal Engineering Control Object

The dynamic characteristics of the water level control system of the steam generator of nuclear power plant are more complex,which are non-linear,strong interference and multiple conditions.As the thermodynamic system of nuclear power plant becomes more and more complex and large,it is necessary to improve the control performance of the system by studying new control algorithm.The ADRC does not rely on the mathematical model of the system controlled object,and has good control performance in time-varying and nonlinear control system.By analyzing the performance of ADRC,the improved ADRC controller is applied to the water level control system of steam generator and the parameters of ADRC are optimized by using the improved genetic algorithm.Firstly,the principle and function of three modules of ADRC are analyzed in detail,and the rule of parameter setting is put forward.Combined with the specific second-order control object,the control parameter performance of the controller is simulated and analyzed.Secondly,a new improved tracking differentiator is proposed.Through the analysis and study of several common tracking differentiator’s acceleration functions,it is found that the performance of the tracking differentiator is mainly related to the acceleration function.In this paper,the hyperbolic tangent functio n with nonlinear smoothness is chosen as the acceleration function of the tracking differentiator,and the stability of the system is proved by using Lyapunov’s second theorem,then the phase plane method is used to guide the tuning of the parameters,and the specific parameter setting scheme is given by sweep frequency test.Through the simulation experiment,it is proved that the hyperbolic tangent tracking differentiator has good control effect.Finally,an improved ADRC controller is applied to the the rmal control object.Aiming at the problems of multiple conditions,nonlinearity and large delay in the water level control system of steam generator in nuclear power plant,the improved ADRC controller is applied to the water level control system of steam generator and the parameters of ADRC are optimized by using the improved genetic algorithm.In order to verify the control effect of the improved controller,the improved ADRC control system and the Feedforward Cascade PID Water Level control system are compared,the results show that the improved ADRC control system has better rapidity,stability,robustness and good immunity.