METHOD FOR PROTECTING A MATRIX CONVERTER AGAINST OVERVOLTAGES AND AN ACTIVE OVERVOLTAGE DEVICE

摘要

The invention relates to a method for protecting a matrix converter (28) having nine bi-directional circuit-breakers (2) which are arranged in a 3x3 switch matrix. The invention also relates to an active overvoltage protection device. According to the invention, 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 (2) of the matrix converter (28) are controlled when a predetermined threshold value is exceeded. Overvoltage protection for an entire matrix converter (28) is thus obtained, whereby said converter can be produced easily and is cost-effective.