Steady-State Operation Control of Gyrotrons in Support of Long Pulse Plasma Operation in EAST

In order to realize the 1000-s long pulse operation of the electron cyclotron resonance heating (ECRH) system on experimental advanced superconducting tokamak (EAST), we developed an ECRH steady-state operation control system. Four working modes were designed, namely, manual restart mode, automatic restart mode, timed alternate operation mode, and protection trigger alternate operation mode. The field-programmable gate array (FPGA)-based NI cRIO was used as the control device, and the LabVIEW was used to write the program. The system has a quick response and accurate timing sequence and can realize the long-pulse steady-state operation of the gyrotrons in EAST ECRH system. The steady-state operation control system has been verified in nearly two rounds of EAST experiments, helping EAST achieve the 1056-s long pulse discharge.