X-ray computed tomography imaging apparatus, x-ray high-voltage apparatus, and x-ray control method

An X-ray high-voltage apparatus, comprising:

• a memory configured to store characteristic data representing a relationship between a filament current value and a tube current output value in a case of switching of the tube voltage to be applied to an X-ray tube between a first tube voltage and a second tube voltage lower than the first tube voltage;
• tube voltage control circuitry configured to switch the tube voltage to be applied to the X-ray tube between the first tube voltage and the second tube voltage;
• tube current setting circuitry configured to set a tube current setting value for periodically modulating a tube current of the X-ray tube in parallel with the switching between the first tube voltage and the second tube voltage, the tube current setting circuitry being configured to set a first tube current setting value at a time of application of either the first tube voltage or the second tube voltage, whichever is a reference tube voltage, and to set a second tube current setting value based on the characteristic data and the first tube current setting value at a time of application of the other one of the first tube voltage or the second tube voltage;
• and
• tube current control circuitry configured to switch between tube current feedback control based on the first tube current setting value at the time of application of the reference tube voltage, and tube current feedback control based on the second tube current setting value at the time of application of said other tube voltage, in synchronization with switching between the first tube voltage and the second tube voltage.

An X-ray control method, comprising:

• a step of switching a tube voltage to be applied to an X-ray tube between a first tube voltage and a second tube voltage lower than the first tube voltage;
• a step of setting a tube current setting value for periodically modulating a tube current of the X-ray tube in parallel with switching between the first tube voltage and the second tube voltage, in such a manner that a first tube current setting value is set at a time of application of either the first tube voltage or the second tube voltage, whichever is a reference tube voltage, and a second tube current setting value based on characteristic data and the first tube current setting value is set at a time of application of the other one of the first tube voltage or the second tube voltage, the characteristic data representing a relationship between a filament current value and a tube current output value in a case of switching of the tube voltage to be applied to the X-ray tube between the first tube voltage and the second tube voltage;
• and
• a step of switching between tube current feedback control based on the first tube current setting value at the time of application of the reference tube voltage, and tube current feedback control based on the second tube current setting value at the time of application of said other tube voltage in synchronization with the switching between the first tube voltage and the second tube voltage.