Control of discharge in high voltage fluid insulation

A control system for controlling deionization in an instrument which produces ionizing radiation, the instrument including:

• a high voltage source of charge and ionizing radiation, a housing filled with insulating fluid and containing the high voltage source;
• an insulator to which the high voltage source is mounted so that the source is spaced from the housing, at least one collector electrode arranged in the housing such that the high voltage source preferentially discharges to the at least one collector electrode, and discharge rate limiting means;
• wherein the control system is configured to:
• determine a level of ionization of the insulating fluid through the amount of discharge to the at least one collector electrode, and control the discharge rate limiting means to deionize the insulating fluid at a controlled discharge rate and thereby maintain the maximum rate of discharge below a predetermined current.

A method for controlling deionization including:

• providing an instrument which produces ionizing radiation, the instrument including a high voltage source of charge and ionizing radiation, a housing filled with insulating fluid and containing the high voltage source;
• an insulator to which the high voltage source is mounted so that the source is spaced from the housing, at least one collector electrode arranged in the housing such that the high voltage source preferentially discharges to the at least one collector electrode, and discharge rate limiting means;
• determining a level of ionization of the insulating fluid through the amount of discharge to the at least one collector electrode;
• and
• controlling the discharge rate limiting means to deionize the insulating fluid at a controlled discharge rate and thereby maintain the maximum rate of discharge below a predetermined current.