Five level high power motor drive converter and control system

A method of controlling a high power motor drive converter including three direct current busses, a five level hybrid neutral point clamped (NPC) output power conversion stage comprising three NPC phase bridges including switches and coupled in a wye configuration through a neutral point, each NPC phase bridge receiving power on a respective one of the three direct current busses, and three isolated split series-connected DC capacitor banks each coupled in parallel to a respective one of the three NPC phase bridges, the method comprising:

• selecting switch positions with active control of neutral voltages by using space vector modulation to control a magnitude and a rotation of a reference voltage vector in a complex voltage plane.

A method of controlling a high power motor drive converter including three direct current busses, a five level hybrid neutral point clamped (NPC) output power conversion stage comprising three NPC phase bridges including switches and coupled in a wye configuration through a neutral point, each NPC phase bridge receiving power on a respective one of the three direct current busses, and three isolated split series-connected DC capacitor banks each coupled in parallel to a respective one of the three NPC phase bridges, the method comprising:

• selecting switch positions with active control of neutral voltages by using feedforward sine-triangle modulation with third harmonic injection applied to each of the three NPC phase bridges.

A method of controlling a high power motor drive converter including three direct current busses, a five level hybrid neutral point clamped (NPC) output power conversion stage comprising three NPC phase bridges including switches and coupled in a wye configuration through a neutral point, each NPC phase bridge receiving power on a respective one of the three direct current busses, and three isolated split series-connected DC capacitor banks each coupled in parallel to a respective one of the three NPC phase bridges, the method comprising:

• selecting switch positions that apply a space vector equivalent triplen harmonic waveform injection to each of the three NPC phase bridges to provide active control of neutral voltages.

A method of controlling a high power motor drive converter including three direct current busses, a five level hybrid neutral point clamped (NPC) output poser conversion stage comprising three NPC phase bridges including switches and coupled in a wye configuration through a neutral point, each NPC phase bridge receiving power on a respective one of the three direct current busses, and three isolated split series-connected DC capacitor banks each coupled in parallel to a respective one of the three NPC phase bridges, the method comprising:

• selecting switch positions with active control of neutral voltages by using feedforward sine-triangle modulatin with zero sequence injection applied to each of the three NPC phase bridges.

A method of controlling a high power motor drive converter including three direct current busses, a five level hybrid neutral point clamped (NPC) output power conversion stage comprising three NPC phase bridges including switches and coupled in a wye configuration thourgh a neutral point, each NPC phase bridge receiving power on a respective one of the three direct current busses, and three isolated split series-connected DC capacitor banks each coupled in parallel to a respective one of the three NPC phase bridges, the method comprising:

• selecting switch positions with active control of neutral voltages by using feedforward sine-triangle modulation with discontinuous modulation injection.