PURPOSE: To provide an AC high voltage generator having wide control range for the DC component of load current in which power loss of bleeder resistor is reduced.
CONSTITUTION: Upon increase of reference voltage VR at terminal P2, current of high voltage transistor Tr 3 constituting a series regulator increases and the output voltage of a converter transformer T2 constituting a DC variable output power supply drops. Upon decrease of the reference voltage VR, current of the high voltage transistor decreases and the output voltage of the converter transformer T2 increases. In such a manner, the series regulator and the DC variable output power supply cooperate to widen the control range of the DC component of load current. Since negative current is limited by means of the high voltage transistor Tr 3 when the DC component is close to zero and the output voltage of the converter transformer T2 drops when the DC component has a high negative value, power loss of bleeder resistor is reduced as compared with conventional one.