Engineering design of LabVIEW based prototype software development for 45.6 MHz, 100kW ICRH DAC

Abstract

Ion Cyclotron Resonance Heating (ICRH) Data Acquisition Control system (DAC) for 100kW, 45.6 MHz has been conceptualized for RF ICRH experimental activities in tokamak. This system will be used for control and monitoring for 2 kW, 20 kW and 100 kW RF amplifier stages respectively. Each lower stage amplifier output is fed to next higher stage amplifier. ICRH system consists of different power supplies for each stage. First two stages need single high voltage power supplies and 100 kW stage needs four power supplies named plate, filament, screen grid and control grid. For failsafe operation of the system, it needs DAC for control, monitor and synchronization of each RF stage respectively. As per requirement of the DAC, it needs 32 analog inputs, 32 digital inputs, 16 digital outputs and 4 analog outputs with 4 counter channels for synchronization of the system. This paper will describe engineering design of LabVIEW based DAC for 45.6 MHz, 100 kW ICRH system. There are three different threads for application development. (1) Data monitoring in graph/chart form as well as textual values which runs on every 100ms timescale periodically. (2) Control and interlocking for failsafe operation of ICRH system which will be catered by different digital and analog channels. Counter/timer cards will be used for triggering as well as pulse generation as per experiment requirement. (3) Data plotting after shot analysis. The data acquisition hardware should be facilitated with 32 analog inputs, 48 digital input/output and 4 analog outputs. User interface will be designed in LabVIEW with control logic implementation. DAC hardware low device driver should communicate with application logic which will be interfaced with user interface module. National Instruments (NI) data acquisition hardware will provide sufficient channels with required resolution needed for DAC.