The described AC/DC power convertor (rectifier) converts AC power into DC power and supplies the DC power to a load. A reference voltage adjusting circuit generates a desired voltage Vdc<*>. A rectifier is designed for an output voltage which is equal to the desired voltage Vdc<*>. A control device compares the voltage across the load and the desired voltage Vdc<*> and generates a command for a pulse width modulator convertor in order to control the pulse width modulator convertor to output power corresponding to the difference between the desired voltage Vdc<*> and the voltage across the load when the voltage across the load drops below the desired voltage Vdc<*>. When the voltage across the load is not less than the desired voltage Vdc<*>, only the rectifier feeds DC voltage power to the load. <IMAGE>
