Abstract: The microwave power source of 3MW ECRH system in HL-2A tokamak is a type of CPD (collector potential depression) gyrotron, which is powered by two kinds of high voltage power sources (PS), cathode PS and anode PS. The function of cathode PS is to offer beam current, and the function of anode PS is focused on two aspects, one is to accelerate the electrons at the region of resonant cavity and the other is to reduce the speed of electron after resonant cavity to decrease the heat load of collector. This design can increase the efficiency of the gyrotron up to 50%. The problems caused by different working condition of different sub-system when the six gyrotrons operated simultaneously, were resolved by optimizing the operating parameters of cathode, anode and other auxiliary PS. In the experimental campaign, six sets of 68GHz ECRH sub-system were operated on parallel at first time and the maximum output power of six gyrotrons was up to 2.5MW, reaching 83% of rating value, and the high power ECW heated the plasma adequately.

Key words: Gyrotron, Superconducting magnet, Electron cyclotron resonance heating, HL-2A tokamak

摘要： HL-2A装置3MW ECRH系统采用双高压电源形式的电子回旋管，阴极高压电源为回旋管提供加速束电流，阳极高压电源对通过转换区后的束电流施加减速作用，利于回旋管收集极吸收。根据回旋管运行特点和各回旋管不同的工作特性，合理优化回旋管阴极、阳极高压电源工作电压和其他参数。通过远程监控系统，使同时工作的回旋管处于较好的工作状态，充分提高HL-2A装置ECRH系统多管运行的微波输出功率。实验中，6支回旋管同时运行时，微波最高输出功率2.5MW，达到设计额定值83%，使HL-2A装置中等离子体得到了有效的加热。

关键词: 回旋管, 超导磁体, 电子回旋加热, HL-2A装置