| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique for providing an AC load with direct current power of a battery in economically inexpensive method without using an inverter.SOLUTION: The auxiliary power unit makes direct current power of a battery to directly overlap with alternating-current power of a commercial power supply by a battery connected in series between a power supply line of a commercial power supply and a load. Sign of the direct current power that overlaps with the alternating-current power is switched over in accordance with a voltage phase of the commercial power supply. |
