The Intelligent Measurement And Control System For Plasma Density Based On Superconducting Tokamak

To develop clean and safe new energy is mankind’s common expectations, and nuclear fusion is one of the main directions for the future new energy’s development. At present, tokamak is the major experimental device for nuclear fusion all around the world. Based on the domestic ITER supporting project, this thesis set up an advanced plasma electron density intelligent control system for the under construction device—J-TEXT tokamak.In the tokamak discharge experiments, the requirement is to control the plasma electron density to quickly achieve a higher value and remain stable. This thesis took the development experience of the EAST device as a guide, and optimized the system’s software and hardware configuration, designed a plasma density control system based on the up and down machines with two different operating systems for J-TEXT. This structure gives full play to the Linux system’s real-time, stability, xcellent network performance, and the Windows system’s human-machine interaction performance.The thesis introduced each module of the system, and expatiate the up and down machines design.As the system’s communication problem, this thesis also realized real-time communication and data transmission between the up and down machines by using the Socket technology to design a client and server communication program, and guaranteed the system’s stability of coordination operation.Tokamak density control system as a typical feedback control system, its real-time performance in the data acquisition is the key to decide the system performance. Therefore, this thesis based on the double buffer mode acquisition mode of the data acquisition card PCI DAQ2010to design and develop the plasma density high speed data acquisition channel. According to the testing results, using nondestructive real-time LZO compression algorithm for data compression can improve the efficiency of data transmission and further meet the needs of the experiment.At the moment, the plasma density control systems all use the traditional PID controller, which though with simple structure and stable performance, real-time performance and tracking capability still needs to be optimized. This thesis combined with intelligent method, researched the tokamak plasma density control system’s intelligence, and proposed the density control system based on neuroendocrine controller. According to the device’s real-time density state, this system could adjust the control parameters online in the discharge process. Through the tokamak mechanism model, we made intelligent PID and conventional PID simulation, and compared their results, which showed that the intelligent PID had advantages in real-time and stability.The main contribution of this thesis is building a stable and effective plasma density control system that satisfied the tokamak experiment’s requirement for real-time performance and realized the long time stable experimental data acquisition. Finally, we put forward the intelligent solution for tokamak density control system, in order to provide a theoretical basis for the realization of the later intelligent system.