Method for protection of a matrix converter against overvoltages, and an active overvoltage device

摘要

A method and a device for protecting a matrix converter is disclosed. The matrix converter has nine bi-directional circuit-breakers which are arranged in a 3x3 switch matrix. A highest potential is detected from all input and/or output potentials or from all input potentials and at least one output potential. Bi-directional circuit-breakers of the matrix converter are controlled when a predetermined threshold value is exceeded. This arrangement protects the entire matrix converter from overvoltages. The converter can be produced easily and cost-effectively.