Abstract: An uninterruptable power supply device includes a mains commutation conductor, a voltage intermediate circuit converter having an associated control device, an output filter comprising a transformer with high leakage inductance and filter capacitors, a mains reset device having an associated control device, and a manual bypass switch. A frequency converter (32) from drive technology is used as the converter, an input filter is connected upstream of this frequency converter, and a battery coupling apparatus is connected to its DC busbar connections. In this way, it is possible an uninterruptable power supply device may be provided which uses the technical and economic synergies from drive technology using commercially available components from drive technology and using UPS-specific components.

Abstract: An apparatus for coupling a battery to a mains-powered Sc link circuit of a converter. The this apparatus has two capacitors and two converter bridge arms which are each connected electrically in parallel with a capacitor. The apparatus also includes an inductor which connects the centre terminals of the two converter bridge arms to one another, and a semiconductor power switch which makes it possible to connect the positive terminals of the two converter bridge arms. In addition, the apparatus includes a control electronics with downstream driver stages which control electronics use determined actual values of this apparatus, a mains failure signal and an inductor current setpointvalue to generate control signals. A battery coupling apparatus is thus obtained by means of which the battery is not continuously loaded with alternating current, and the opportunity for battery maintenance exists in order to increase the battery life.