Development of the body power supply for ECRH on EAST

Abstract Electron cyclotron resonance heating (ECRH) plays a major role of plasma heating and it is also an important way of inhibiting plasma instability. The high frequency modulation operation of ECRH system is proposed, which is helpful for the suppression of non-classical tearing modes (NTMs). A 30kV/100mA high voltage body power supply (BPS) with 5 kHz modulation ability for 1MW/1000s Gyrotron has been developed. The BPS adopts linear power supply technology, switching power supply technology and pulse step modulation (PSM) technology. A modulation from 0 up to 100 % is possible, and the rising time is less than 20us. The output voltage ripple factor of the BPS is less than 0.5%. The test results show that the BPS can meet the requirements of ECRH system, and it has strong generality, which can provide reference for the design of other body power supply.