Initial operation of 3 MW dual output high voltage power supply with IC RF system

Abstract

Pulse Step Modulation (PSM) based High Voltage Power Supplies (HVPSs) are widely used in fusion research and other applications viz. broadcast transmitters, particle accelerators and neutral beam injectors because of inherent advantages of modular structure, high accuracy and efficiency, low ripple and fast dynamics. Typical Ion Cyclotron Radio Frequency (IC RF) system composed of cascaded connection of Driver stage (130 kW RF output) and End stage (1500 kW RF Output) would need two power supplies. A novel concept of tapping two outputs from single PSM based HVPS is attempted for the first time. PSM based 3 MW HVPS is developed with dual output to feed anode voltage of Driver (up to 18 kV) and Final Stage (up to 27 kV). Controller for the HVPS is designed to suit requirements during local operation and remote operation. In Local operation mode, protection interlocks with in the HVPS are integrated while remote mode has additional interlocks from IC RF Amplifiers system. Field integration of the controller is achieved through fiber optical links to avoid Electro-Magnetic interferences. Present article discusses initial experience of dual output HVPS with IC RF amplifiers, pre-integration validation campaigns including qualification for energy limits. The paper also presents the performance of HVPS at full rated capacity of 2800 kW continuous duty to support 1.5 MW IC RF system.