High voltage power supply system including inverter controller

A high voltage power supply system comprising:

• means for producing a command signal to determine a time period of X-ray irradiation;
• a DC-to-DC converter circuit including first switching means for switching a DC (direct current) input voltage so as to produce a DC low output voltage in response to said command signal during only said time period of X-ray irradiation, and filtering means having at least a capacitive element for filtering said DC low output voltage to produce a filtered DC low output voltage;
• a DC-to-AC inverter circuit including second switching means connected to said DC-to-DC converter circuit, for switching said filtered DC low output voltage so as to produce an AC (alternating current) low voltage, and a step-up transformer having a primary winding and a secondary winding magnetically coupled to said primary winding, said primary winding being connected to said second switching means so as to receive said AC low voltage and said secondary winding including an AC high voltage for the X-ray irradiation by transforming said AC low voltage applied to said primary winding;
• and
• an inverter control circuit coupled to said second switching means of the DC-to-AC inverter circuit, for controlling, in response to said command signal, an operation time period of said DC-to-AC inverter circuit to be longer than said time period of X-ray radiation so as to discharge a residual charge stored in said capacitive element of said filtering means.