| 摘要 |
Provided are a first period in which a voltage Vin is equal to or higher than a positive first reference voltage, a second period in which the voltage Vin is equal to or lower than a negative second reference voltage, and a third period in which the voltage Vin is between the first reference voltage and the second reference voltage. In the first period, second and third switching elements are switched ON, and first and fourth switching elements are alternately switched ON/OFF. In the second period, the first and fourth switching elements are switched ON, and the second and third switching elements are alternately switched ON/OFF. In the third period, the first and second switching elements are switched ON, and the third and fourth switching elements are switched OFF. The voltage Vin is stepped down to a predetermined AC voltage Vo while ensuring a release path for inductive energy accumulated in a reactor. |
