Research On The Temperature Control System Of Plane Blackbody Radiation Source Based On ADRC

Blackbody radiation source is a key equipment in the traceability process of radiation temperature measurement,and its temperature control is a complicated process with nonlinearity,time delay and inertia.Active Disturbance Rejection Control(ADRC)is a nonlinear control method that is developed on the basis of PID control.On the one hand,it inherits the following advantages of PID control thought: the simple structure and independent of the mathematical model of controlled object;on the other hand,its disturbance estimation compensation function is used to improve the anti-interference ability of the controller,and therefore it has better robustness when it control the actual process with all sorts of uncertain factors.Firstly,after introducing the temperature control requirements of the plane blackbody radiation source,this paper establishes an approximate mathematical model,and research on the temperature control by the mathematical model.The basic principle of PID and nonlinear PID is introduced and the simulation is carried out.Next,we introduce and verify the stability of ADRC for its practical application.In the practical application process of ADRC,modifying parameters 0b so as to improve the response speed when exist small error and reduce the transient time.On the other hand,this paper proposes a kind of ADRC algorithm,SEADRC,based on disturbance estimation separation in order to establish balance between the size of control input and the estimated velocity of the disturbance and prevent the occurrence of saturation phenomenon of disturbance estimation.Secondly,the experiment platform of temperature control system was designed and built.We introduce the basic parameters and principles of the hardware of the control system,and the hardware selection and networking of the control system based on the Compact RIO controller.The graphical programming of LabVIEW software is used to realize the digital discretization of the ADRC algorithm.Finally,the temperature control experiment of the plane blackbody radiation source is carried out based on the experimental platform.Compare with the control effect of SEADRC and traditional ADRC on the basis of the robustness of the control algorithm,and verify the effectiveness of the proposed method in the simulation experiment.Then,we use the traditional PID control and nonlinear PID control for temperature control experiments and compared with the SEADRC proposed,and further verify the temperature control quality of the SEADRC.The experimental results show that ADRC algorithm can effectively improve the quality of temperature control of blackbody radiation source,temperature stability can reach 9 mK/10 min,and has stronger anti disturbance ability.