Development of Cockcroft–Walton‐type high‐voltage DC generator with RF air‐core transformer

A new Cockcroft–Walton (CW)‐type high‐voltage DC generator with RF air‐core transformer used as a step‐up transformer has been developed. The design concept of the air‐core transformer is shown, which is operated on the resonance condition between the inductance of the secondary coil and the stray capacitance of CW circuit with the conical‐type coil structure. Adapting the RF air‐core transformer to CW circuit with DC‐300 kV 100 mA, excellent performances have been demonstrated. In the new CW circuit, it results in downsizing of capacitors to operate at higher frequency than conventional ones, and reduction of the volume by approximately 40% has been shown in the typical DC generator with 1 MV 100 mA. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 160(1): 18–26, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20500