Operation of modular multilevel matrix converters with failed branches

Modular Multilevel Converters have a large number of advantages at high voltage and power levels. Due to their modular structure, they offer easy scalability, high quality output waveforms, and superior availability, to name a few. This paper aims at further increasing the availability of the Modular Multilevel Matrix Converter. A new method allows to operate the converter even in the case that a complete branch is lost. This is achieved by a new control method to operate six of the remaining branches as a reduced matrix converter. Smooth transition from full matrix to reduced matrix operation is achieved without shutdown of the system.