Abstract: A method of controlling a resonant push-pull converter is disclosed. The resonant push-pull converter includes a transformer, a first switch, a second switch, a resonant tank, and a rectifying circuit. The method includes a step of a fixed on-time control. In the fixed on-time control, a first control signal with a fixed on-time is used to control the first switch, and a second control signal with the fixed on-time is used to control the second switch so that the first switch and the second switch are alternately switched.

Abstract: An uninterruptible power supply includes a switching unit, a charging unit, an energy storage unit, a conversion unit, and a control unit. When an input power source is available, the switching unit provides a first output power source and the charging unit converts the input power source into a first power source to provide the first power source to the control unit and to charge the energy storage unit. When the input power source is not available, the conversion unit converts the electricity of the energy storage unit into a second output power source and provides the second output power source. When the input power source is not available, the conversion unit provides a second power source to the charging unit so that the charging unit converts the second power source into the first power source and provides the first power source to the control unit.

Abstract: An uninterruptible power supply apparatus includes a switch, a first inductor, a direct current controlling unit, a first bridge arm, a second bridge arm and a third bridge arm. When the switch switches the first inductor coupled to an alternative current (AC) power, the AC power converts into a bus voltage via the first inductor, the first bridge arm and the second bridge arm, and converts into an output power via the second bridge arm and the third bridge arm. When the switch switches the first inductor coupled to a DC power, the DC power converts into the bus voltage via the DC controlling unit and the first inductor, and converts into the output power via the second bridge arm and the third bridge arm.

Abstract: An uninterruptible power supply includes a switching unit, a charging unit, an energy storage unit, a conversion unit, and a control unit. When an input power source is available, the switching unit provides a first output power source and the charging unit converts the input power source into a first power source to provide the first power source to the control unit and to charge the energy storage unit. When the input power source is not available, the conversion unit converts the electricity of the energy storage unit into a second output power source and provides the second output power source. When the input power source is not available, the conversion unit provides a second power source to the charging unit so that the charging unit converts the second power source into the first power source and provides the first power source to the control unit.

Abstract: An inverter apparatus includes a first switch, a second switch, a third switch, a fourth switch, a load detection unit, and a control unit. The first switch and the fourth switch form a first switch assembly, and the second switch and the third switch form a second switch assembly. The control unit selects a control mode to be that two switches of the first switch assembly are not turned off and at least one switch of the second switch assembly is turned off, or two switches of the second switch assembly are not turned off and at least one switch of the first switch assembly is turned off, or two switches of the first switch assembly and two switches of the second switch assembly are not turned off.

Abstract: An uninterruptible power supply apparatus includes a switch, a first inductor, a direct current controlling unit, a first bridge arm, a second bridge arm and a third bridge arm. When the switch switches the first inductor coupled to an alternative current (AC) power, the AC power converts into a bus voltage via the first inductor, the first bridge arm and the second bridge arm, and converts into an output power via the second bridge arm and the third bridge arm. When the switch switches the first inductor coupled to a DC power, the DC power converts into the bus voltage via the DC controlling unit and the first inductor, and converts into the output power via the second bridge arm and the third bridge arm.