Connection branch of a three-level inverter and three-phase frequency inverter

摘要

Disclosed is switch branches for a three-level converter and a three-phase three-level converter. The switch branches for the three-level converter comprise a first diode (D1) and a second diode (D2), a third diode (D3), a fourth diode (D4), a first semiconductor switch (S1) and a second semiconductor switch (S2), wherein the first diode (D1) and the second diode (D2) are serially connected between a direct voltage positive electrode (Udc+) and an alternating voltage electrode (AC), the third diode (D3) and the fourth diode (D4) are serially connected between a direct voltage negative electrode (Udc-) and the alternating voltage electrode (AC), the first semiconductor switch (S1) is connected between a direct voltage neutral electrode (NP) and a connecting point between the first diode and the second diode, the second semiconductor switch (S2) is connected between the direct voltage neutral electrode (NP) and a connecting point between the third diode and the fourth diode, the first diode (D1) and the first semiconductor switch (S1) are positioned in a semiconductor module (10) specially owned by a first switch branch, and the fourth diode (D4) and the second semiconductor switch (S2) are positioned in a semiconductor module (20) specially owned by a second switch branch.