Data Transfer Methods in Real-Time Controller of Ion Cyclotron High-Voltage Power Supply

Ion cyclotron high-voltage power supply (IC-HVPS) with dual output (27 kV, and 15 kV, 3 MW) is operational at ITER-India laboratory with a 1.5-MW Diacrode-based RF source to be used for ion cyclotron RF system. The controller for IC-HVPS is designed with LabVIEW Real-time (RT) peripheral component interconnect eXtension for Instrumentation (PXI) controller to support all control and monitoring operations of the pulse step modulation-based power supply. Besides regulation of output voltage, the controller supports all essential features like fast dynamics, low ripple, and protection for source and loads. This is managed by close integration between RT system and field-programmable gate array (FPGA) inside the controller. Two types of data transfers inside the RT controller are implemented: 1) between FPGAs and RT controller and 2) among internal algorithms. RT controller and FPGAs are interconnected through PXI bus. Critical functions, signal generations, monitoring and data acquisition, and interfaces are assigned to FPGAs and managed by RT operating system installed in the controller. This paper discusses different techniques used mostly for transfer of information between RT controller and FPGAs. Information includes critical signals, data, measurements, commands, and configuration required for internal algorithms. Discussion also includes some specific choices made for synchronized and asynchronous transmission of parallel and sequential data.