| 摘要 |
Multilevel DC to AC power converter has three DC inputs (IN1, IN2, IN3) for receiving, respectively, three DC voltages (V1,V2,V3), wherein V1>V2>V3, one AC output (OUT1) for delivering an AC voltage (Va), a set of at least six switching means (T1,T2,T3,T4,T5,T6) arranged in a symmetric pyramidal fashion, and switch control means for controlling an ON/OFF state of each of the six switching means. The switch control means is configured such that the top two switching means (T5,T6) are switched ON and OFF in a complementary fashion and, exclusively, at a fundamental frequency (Fa) of the AC voltage to be delivered at the AC output (OUT1), whereas at least some of the other four switching means (T1,T2,T3,T4) are switched ON and OFF at higher frequencies. The top two switching means (T5,T6) are hence subject to lower switching losses, thereby increasing the overall efficiency of the converter. |
