Design Of Digital Controller Of Power Supply And Data Processing In HIAF

The power supply system in the High Intensity heavy ion Accelerator Facility(HIAF)comprises a large number of diverse power sources with complex topological structures and significant technical challenges.Different types of power sources exhibit distinct control requirements for digital controllers.This study presents a digital controller design for three types of power sources in HIAF,employing a hardware platform that centers around a field-programmable gate array(FPGA)as the core control unit and incorporates various functional boards.The proposed controller design has been successfully validated on corresponding power source prototypes,demonstrating its feasibility,reliability,and effectiveness in addressing the specific engineering requirements of HIAF.The digital controller solution,featuring multiple control core units,facilitates data exchange between FPGA and digital signal processors(DSPs)within the boards via the External Memory Interface(EMIF)bus.Moreover,it enables a combined control mode between FPGA and Programmable Logic Controllers(PLCs)through serial communication in a master-slave configuration.Leveraging high-speed optical fiber transceivers as the communication medium at the board level,the controller design successfully integrates into a distributed master-slave control architecture.Up to 15 digital controllers employing this solution have been successfully deployed in the prototype of the Booster Ring,a fully energy-storage fast-cycling pulsed power supply within HIAF,and have operated reliably for a period of two years,thereby substantiating the functionality and stability of the digital controller solution.To enhance the output current and load-side magnetic field stability of the DC power sources,a feedback correction control scheme is proposed,which operates at the front end of the power sources.By utilizing multiple closed-loop control strategies based on current and magnetic field feedback values,the scheme employs a limited hysteresis control policy to correct the current setpoint,effectively improving the stability of the DC power source output current and load-side magnetic field.Implementing the correction at the power source end eliminates the need for highlatency long-distance communication links for centralized correction at the control layer.Experimental results obtained from applying this scheme to the dipole magnet power supply of the Heavy Ion Research Facility in Lanzhou-Cooling Storage Ring experimental ring(HIRFL-CSRe)demonstrate a threefold increase in current stability and a twofold increase in magnetic field stability.Furthermore,an edge computing mode data processing scheme is proposed,utilizing the surplus computational resources within the digital controller for data computations.The scheme accommodates the data analysis requirements of different power sources,including pre-filtering and storage of data in various power source states,data analysis at the power source input stage,and Fast Fourier Transform(FFT)computations,among others.Performing data processing at the power source end not only enables more timely analysis of power source data but also reduces the volume of communication data between the power source end and upper-level control equipment,establishing a solid foundation for the realization of intelligent control in digital power sources.