Design And Implementation Of A Fast Control System For Plasma Vertical Displacement Based On High Speed Acquisition

Most of tokamak devices are designed for elongated configuration plasma discharge,but the plasma equilibrium configuration with elongated interface has natural axisymmetric vertical instability,which is one of the main mechanisms to cause large disruption.Although the passive structure of EAST device can restrain the vertical instability of plasma,the active control of the vertical instability with inner coils(IC)which are closer to plasma and has stronger capability is still needed.In the plasma control system PCS,the vertical displacement of the plasma is calculated in real time by electromagnetic measurement signal,and the rapid change of the vertical displacement is controlled by adjusting the current of the fast inner coils.The command in each control cycle is transmitted to the IC power supply terminal in real time through the RFM network with low delay.The control ability of plasma vertical displacement is related to the IC power supply and the response speed of the whole system.The factors that affect the response time of the system include the response speed of the power supply itself,the control cycle of PCS,the command transmission delay between PCS and the IC power supply,etc.With the upgrading of the fast control power supply,the response delay of the power supply itself has been reduced to about 100 microseconds.How to reduce the control calculation and command transmission has become the research motivation of this thesis.In order to realize the rapid control of the vertical displacement of the plasma,this thesis not only designs the acquisition and transmission of the vertical displacement,but also studies the rapid control of the vertical displacement in a separate subsystem.In this thesis,acq424elf-32,a high-speed synchronous acquisition equipment of dtacq2106 series,is used to realize the synchronous acquisition of 50 kHz electromagnetic measurement data,which is transmitted to the vertical displacement control subsystem server in real time through optical fiber transmission card.The vertical displacement calculation,filtering processing,PID feedback control calculation and command sending are completed in a control period of 20 microseconds,greatly improving the control calculation and command sending transmission response speed.According to the functional requirements,the system is tested and verified.In the actual experiment process,the overall process function of the system is tested and the delay of control command transmission is tested successfully.The results show that the design goal of the system is achieved successfully.Figure [34] table [4] reference [50]...