Multi-level voltage source converter, DC power transfer system and method and device for troubleshooting

摘要

A voltage-source multi-level converter, including a phase unit (0). The phase unit (0) includes a first bridge arm (100) and a second bridge arm (200), where a first terminal of the first bridge arm (100) is a first DC terminal (P) of the phase unit (0), and a first terminal of the second bridge arm (200) is a second DC terminal (N) of the phase unit (0); a second terminal of the first bridge arm (100) and a second terminal of the second bridge arm (200) are shorted together, as an alternating-current terminal (A) of the phase unit (0); the first bridge arm (100) includes first modules (101) and one first reactor (102) connected in series, where a first terminal of the first reactor (102) is connected to the alternating-current terminal (A), a second terminal (X1) thereof is connected to a first terminal of the first modules (101), and a second terminal of the first modules (101) is connected to the first DC terminal (P); the second bridge arm (200) includes second modules (201) and one second reactor (202) connected in series, where a first terminal of the second reactor (202) is connected to the alternating-current terminal (A), a second terminal (X2) thereof is connected to a first terminal of the second modules (201), and a second terminal of the second modules (201) is connected to the second DC terminal (N); and a parallel fault shunt circuit (300) is connected between the second terminals (X1, X2) of the first reactor (102) and the second reactor (202). Also disclosed are a DC power transmission system and a fault processing method and device.