Design and realization of very high voltage DC generators

Abstract

X-RIS is active in the development and supply of innovative solutions in digital radiology for the industry and the security. X-RIS provides user-friendly and pragmatic solutions that fit at best the application needs. The company is especially known in developing small and portable X-ray generators. The present project aims at developing a new DC power supply for an X-ray generator. The DC supply is supposed to be as small as possible with an operating output voltage of 400 or 600 kV respectively having an output current of 0.25 and 0.15 mA. The size of systems working at a high voltage up to 400 kV is most of the time a few meters in height. Designing a generator that has a size of some centimeters is thus the main purpose. To reach this objective, two kinds of circuits based on the Cockroft-Walton generator are studied: the half-wave and the full-wave multiplier. Through several simulations, the main features of both of them applied in particular cases of this project are exposed. Furthermore, the final choices about the circuit design and the components are detailed. It will be shown through some tests the ways of decreasing the magnitude of the electric field in this high voltage generator. The processes of building up and testing the generator are also explained. Various insulating materials with their advantages and disadvantages are proposed. Finally, the tests suggest to follow some new perspectives that are also highlighted.