Megawatt HV DC Power Supplies

For the injection of heavy, multiply charged ions into accelerators or for injection of cluster ions into fusion reactors, physicists require high-voltage dc power supplies with voltages in the range of 0.5 to 3 MV and currents of the order of several hundred milliamperes, and even amperes. Several power supplies in this range have been built recently, some for particle injectors and some for testing UHV dc transmission line components. In 1974, high-voltage dc power supplies with the following output ratings were completed: 2.5 MV/200 mA, 2.2 MV/ 200 mA, 1.2 MV/100 mA, and 1.0 MV/120 mA. All power supplies are built according to the symmetrical Cockcroft-Walton generator principle and are either air-insulated open structures or built into a pressure vessel and insulated with high-pressure sulphur hexafluoride. Based upon theoretical considerations and experience gained with units previously built, it appears feasible to design even more powerful generators.