Regulated high voltage power supply for gyrotrons based on pulse step modulator technology

The Regulated High Voltage Power Supply (RHVPS) which energizes the gyrotrons used in the Electron Cyclotron Resonance Heating (ECRH) system of TCV is based on the Pulse Step Modulator (PSM) technology. The RHVPS [1-2] is designed to minimize active and reactive losses, and to insure an easy operation with high reliability, and low maintenance. RHVPS based on PSM technology has a high energy conversion factor (95%) and a low rejection of harmonics in the power grid. A crowbar is not necessary due to the high reliability and the very fast switch-off of the high voltage of the system. The modular conception minimizes the number of spare parts. The RHVPS is extremely compact (less than 200 m3 for a 6.5 MW unit). For operation at low duty cycle (as in our case, 1%), no cooling is required. The design of the RHVPS will be discussed and the results of the factory tests on a resistive load are presented. (orig.)