Abstract: A power converter and a power converting method are provided. The power converter for converting an ac input voltage at an input terminal thereof into an ac output voltage at an output terminal thereof includes an energy-storing inductor, a first switching circuit coupled to the energy-storing inductor to selectively switch so that the input terminal of the power converter is coupled to the energy-storing inductor, a second switching circuit coupled to the energy-storing inductor and the first switching circuit to selectively switch so that a common terminal of the power converter is coupled to the energy-storing inductor; and a third switching circuit coupled to the energy-storing inductor, the first switching circuit and the second switching circuit to selectively switch so that the output terminal of the power converter is coupled to the energy-storing inductor.

Abstract: An uninterruptible power supply module is provided. The uninterruptible power supply module comprises an input terminal, a direct-current voltage source, a control module, a control arm-bridge module, an inductive element, a power source selection switch, and a switch element. The switch element is turned on before the power source selection switch is connected to the inductive element so that the direct-current voltage supplied by the direct-current voltage source is modulated by the control arm-bridge module to generate an output alternating current voltage to the load. And the switch element is turned off, i.e. not conducting electricity, after the power source selection switch is connected to the inductive element and the direct-current voltage source. Thereby, the use life of the power source selection switch element and the reliability of the uninterruptible power supply module are both increased.

Abstract: A power converter and a power converting method are provided. The power converter for converting an ac input voltage at an input terminal thereof into an ac output voltage at an output terminal thereof includes an energy-storing inductor, a first switching circuit coupled to the energy-storing inductor to selectively switch so that the input terminal of the power converter is coupled to the energy-storing inductor, a second switching circuit coupled to the energy-storing inductor and the first switching circuit to selectively switch so that a common terminal of the power converter is coupled to the energy-storing inductor; and a third switching circuit coupled to the energy-storing inductor, the first switching circuit and the second switching circuit to selectively switch so that the output terminal of the power converter is coupled to the energy-storing inductor.

Abstract: A method of controlling an uninterruptible power supply apparatus (UPS) is provided. The UPS apparatus includes at least an AC input voltage, a DC input voltage and a single-phase AC/AC converter. The single-phase AC/AC converter includes an AC inductor, a bus capacitor, a boost arm, a common arm and a buck arm. The method includes steps of: controlling the bus voltage to have a DC component and full-wave rectifying component, and setting a bus voltage parameter K so that the bus voltage approaches to a full-wave rectifying voltage when K approaches to 1, wherein 0?K?1.