Characteristic Analysis of New Adjustable Power Module for ECRH on EAST

PSM (Pulse Step Modulate) power supply technology is utilized by the ECRH (Electron Cyclotron Resonance Heating) system of EAST(Experimental Advanced Superconducting Tokamak). The adjustable module is a specialized sub-module, which has a function of adjustable output voltage. The silicon carbide semiconductor switches were used to newly developed adjustable module which enhances switching frequency while maintaining an acceptable temperature rise. Furthermore, the new interleaving Buck topology structure enables continuous adjustment of the output voltage and reduces current stress on each power device under full load, thereby enhancing throughput capacity. A two-phase branch interleaving conduction control mode is employed to cancel out the output ripple of the two branches, resulting in reduced overall output ripple. Finally, its output characteristics is analyzed based on the working principle of the new adjustable module. its optimal working mode and corresponding control strategy is discussed in conjunction with overall output requirements of the system.