FIVE LEVEL HIGH POWER MOTOR DRIVE CONVERTER AND CONTROL SYSTEM

摘要

A high power motor drive converter includes: a five level hybrid NPC output power conversion stage including three NPC phase bridges having switches and coupled in a wye configuration through a converter neutral point, each NPC phase bridge receiving power on a respective direct current bus; three isolated split series-connected DC capacitor banks each coupled in parallel to a respective one of the three NPC phase bridges; and a controller for selecting switch positions with ac tive control of neutral voltages. The controller is adapted to select switch position s using feedfood sine-triangle modulation with third harmonic injection, zero sequence injection, and/or discontinuous modulation injection.