Patent ID: 9054526
Filing Date: 2015-06-09
Classification: H02H,H02M

Abstract:
1. A method for operating a converter, wherein the converter comprises a plurality of bridge branches having one or more switching cells connected in series, wherein each bridge branch connects one of a plurality of inputs to one of a plurality of outputs of the converter, the method comprising: monitoring each of the switching cells to determine a fault; if a fault is identified in a first switching cell, triggering one of the triggering elements for short-circuiting switching cell connections if the fault identified in the first switching cell is not followed by identification of a fault in a second switching cell within a predetermined period of time; communicating the identification of the fault in the first switching cell to a central monitoring device; starting a timer in the central monitoring device; carrying out a check in the central monitoring device to determine whether occurrence of a fault in the first switching cell is communicated before expiry of a predetermined period of time, triggering at the central monitoring device a relevant triggering element of the first switching cell if a fault in the second switching cell is not communicated during the predetermined period of time; and triggering one of the triggering elements for short-circuiting switching cell connections only if the identification of a fault in a first switching cell, which is not followed by identification of a fault in a second switching cell during a predetermined period of time, has repeatedly occurred for the first switching cell.