Power Supply for Ion Cyclotron Resonance Heating

The latest generation of fusion experiments has stretched Ion Cyclotron Resonance Heating (ICRH) transmitters to their limits, in terms of reliably delivering multi-megawatts of RF power, because the transmitter design is based on 1970s vintage technology. An opportunity exists for advancing this transmitter technology by using an integrated solid-state opening switch. This project will design the complete ICRF transmitter and will work with researchers from Alcator-C Mod to identify, build, and install subsystem upgrades into the existing FMIT RF transmitter. The key upgrade is a pair of high voltage, solid-state opening switches to replace the outmoded ignitron crowbar technology. Phase I demonstrated that the installation of high voltage opening switches can significantly improve transmitter performance and reliability, and completed a preliminary electrical and mechanical design. In Phase II, a high voltage opening switch package for one transmitter will be built and installed. This effort includes integrating the control circuitry for the switches into the existing transmitter controls. Commercial Applications and other Benefits as described by the awardee: In addition to the cost and performance benefits for future ICRH systems such as ITER, the controls and subsystems also should improve the reliability, efficiency, and performance of existing long pulse and CW transmitters. Applications include commercial broadcast transmitters, high energy accelerators, high power radar transmitters, and industrial RF applications in drying, curing, and related processes