Siemens Aktiengesellschaft

Philipp Oschmann

Alexander Hensler

Hubert Schierling

Stefan Pfefferlein

Ulrich Wetzel

Bernd Kürten

Stephan Neugebauer

Thomas Bigl

Ewgenij Ochs

Helmut Brendel

Gerd Hilbinger

Marion Junghänel

A rectifier has at least three outputs at which the rectifier provides a high potential, a low potential and at least one medium potential. Phase voltages of a supply grid can be supplied to the rectifier via feed lines. Inductors are arranged in the feed lines. A clamping circuit has two diode circuits that are connected in series. One of the end points of the series circuit is connected to an output at which the rectifier provides one of the medium potentials. The other end point is connected to another output. The node is connected to a reference potential via an overall capacitor circuit.

Clamping circuit in a rectifier with more than two potentials provided on the output side

A cooling device for heat dissipation from an electronic component includes a heating tube having a heating tube surface, a cooling element having a first cooling element side formed with a slot recess which at least partially encloses the heating tube, and a fiber structure made of fibers and arranged on the heating tube surface in a region in which the heating tube is at least partially enclosed by the slot recess. The fibers on the heating tube surface of the heating tube in the region of the slot recess form a mechanical connection with a cooling element surface of the cooling element.

Cooling device with fiber attachment between heating tube and cooling element

A frequency converter includes a rectifier on an input side and a support capacitor downstream of the rectifier. Input-side phases of the rectifier feed the backup capacitor via multiple half-bridges of the rectifier. The half-bridges have active switching elements and the rectifier is designed as a recovery rectifier. The input-side phases are connected to grid-side phases of a multiphase supply grid via an upstream circuit. Each grid-side phase is connected to one of the input-side phases within the upstream circuit via a respective phase capacitor. A control facility controls the active switching elements when a first charge state of the support capacitor is reached and input-side phase voltages are applied to the input-side phases via the active switching elements. Voltages running in the opposite direction to the grid-side phase voltages are applied to the grid-side phases to which the input-side phases are connected via the phase capacitors.

Frequency converter with reduced pre-charging time

Growing community of inventors

Erlangen, Germany

Philipp Oschmann