The Design Of No.1 NBI Main Control System For HL-2A Device Based On Virtual Instrument Technology

Neutral beam injection（NBI）heating is one of the commonly auxiliary heating methods used for magnetically confined plasma.Large and medium-sized tokamak devices in domestic and overseas are equipped with neutral beam injection heating systems with power capacity ranging from a few MW to several tens of MW.Among all,the control system as the"central nerve"system of the entire NBI heating system,its function,reliability and stability determine the operating efficiency of the NBI heating system.The 1^st NBI heating system of China Circulator 2^nd A（HL-2A）device has been running for more than ten years.Its control system is generally successful,ensuring the safe and reliable work of the system.But the control system is gradually showing many deficiencies,such as large amount of engineering wiring,low timing modulation accuracy and inflexibility,and human-computer interaction interface is not humanized.Therefore,on the basis of the summary in successful design experience of the NBI control system for fusion devices all around the world,combining with the characteristics of the NBI heating system for the HL-2A device,this paper finally decides to use advanced virtual instrument technology,fiber isolation technology and serial communication technology to develop a more reliable and efficient NBI main control system for HL-2A devices.The main control system not only has the basic functions of remote monitoring,logic interlocking and parameter setting of the original main control system,but also the system integration level,anti-interference performance and scalability have been greatly improved.This paper first introduces the working principle and function of the neutral beam injection heating technology in the field of magnetic confinement nuclear fusion,and the composition framework of the NBI heating line for HL-2A device.The currently operating NBI main control system for the HL-2A device is elaborated,including characteristics of the hardware and software platform,and the advantages and disadvantages of the main control system are summarized.Secondly,choosing the mature commercial finished product（COST）equipment,that is,the National Instruments（NI）PXIe bus device as the new core controller,and NI LabVIEW2015 is used to develop the human-computer interaction interface of the main control system.The main interface includes six function modules,such as the monitoring interface,timing setting and timing display,covering the basic functions required by the NBI main control system.This paper analyzes the main function of each module,and gives the design ideas and implementation methods of functional modules.Especially for the design of high-precision timing and protection system of NBI power system,the entire design process is completed from the characteristics analysis of timing waveform to the final digital IO output verification of the timing waveform.The system has good engineering application value.Finally,by analyzing the important functions of related functional modules of the NBI main control system in the NBI power failure diagnosis,the rationality and superiority of selecting the virtual instrument technology to design the NBI main control system are further illustrated.