Siemens Aktiengesellschaft

Eupec Europaeische Gesellschaft Fuer Leistungshalbleiter Mbh & Co. Kg

Reinhold Dillig

Hubert Schierling

Benno Weis

Bernd Herrmann

Reinhold Bayerer

Manfred Loddenkoetter

Sebastian Raith

Thomas Schwinn

Roland Lorz

Michael Kistner

Bernd Roppelt

A frequency converter has an AC-DC converter and an inverter interconnected via a DC link having a first and a second circuit branch interconnected by a DC link capacitor and a commutation capacitor. To protect the AC-DC converter from damage caused by an overcurrent, the first circuit branch includes a choke in which a capacitor-side terminal is connected to a terminal of the DC link capacitor and a switch-side terminal is connected via a semiconductor switch to a DC link terminal of the AC-DC converter and also via a freewheeling diode to the second circuit branch. The semiconductor switch is configured to control a magnitude of an electric current flowing from the AC-DC converter into the DC link capacitor in accordance with a control signal.

Frequency converter with DC link capacitor and method for pre-charging the DC link capacitor

In a frequency converter operated for safety of personnel and/or fire protection via a ground fault interrupter is frequently not able to distinguish between an actual fault current and an operationally generated leakage current. The proposed method addresses this problem by determining a course of a magnitude of a current flowing through the frequency converter, predefining a signal portion which is independent of switching processes within the frequency converter while the frequency converter operates fault-free, checking whether the determined course satisfies a criterion that is predetermined depending on the signal portion, and interrupting the current the determined course fails to satisfy the predetermined criterion.

Frequency converter and method for identifying and blocking a fault current in a frequency converter

A conventional ground fault interrupter in an arrangement with a frequency converter and electrical machines may be accidentally tripped due to operation-related leakage currents. This can be prevented by operating a ground fault interrupter for a frequency converter receiving a mains current in the following manner: receiving switching information about switching operations in the frequency converter, measuring a signal associated with a common mode current in a power line device which conducts the mains current to the frequency converter, determining, based on the switching information, an expected signal expected for the common mode current produced by the switching operations, identifying, based on the measured signal and the expected signal, a fault current, and interrupting the mains power depending on the identified fault current. A ground fault interrupter is hereby provided with an evaluation unit configured to carry out the method.

Method for operating a ground fault interrupter as well as ground fault interrupter for a frequency converter

A power semiconductor module contains a power component and a sensor component. The power component is disposed on a first substrate. The sensor component is electrically and/or mechanically insulated from the power component by being disposed on an individual, separate second substrate. In this manner, disturbances of the sensor system section caused by the power section and its operation can be avoided particularly reliably.

Power semiconductor module

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Memmelsdorf, Germany

Reinhold Dillig