Patent ID: 8553435

Claim:
Device for converting a DC voltage into an AC voltage and vice versa comprising at least one phase leg with a first (Uvp1) voltage source and a first inductor connected in series between a first DC terminal and a first AC terminal and with a second inductor and a second (Uvn1) voltage source connected in series between the first AC terminal and a second DC terminal, where each of the voltage sources comprises at least a first and a second submodule in series-connection, each submodule comprising at least two power electronic switches connected in parallel with at least one capacitor, wherein a passive electronic filter is arranged between the first and the second inductor as well as the first AC terminal and where the parameters of the electronic filter are chosen so that harmonics at twice the fundamental frequency of the AC voltage are reduced, the filter comprises a third and fourth inductor, where the third inductor is arranged between the first inductor and the first AC terminal, the fourth inductor is arranged between the second inductor and the first AC terminal and the third and fourth inductors have the same value.