An X-ray-generator irradiates X-rays at a subject. The X-ray-detector detects the X-rays that have permeated the subject. The rotating body on which the X-ray-generator and the X-ray-detector are installed rotates around the subject. The rotating body is rotated by the drive part. The power source supplies electrical power to the drive part. The step-down part lowers the voltage of the regenerative electrical power generated at the drive part during the deceleration of the rotating body. The accumulation part charges the lowered electrical power. The step-up part raises the voltage of the electrical power from the accumulation part and supplies electrical power to the drive part.
