Otis Elevator Company

Otis Elecator Company

Marinko Kovacic

Shashank Krishnamurthy

Yang Wang

Luis Arnedo

A neutral point clamped, multilevel level converter includes a DC voltage link; a first capacitor coupling one side of the DC link to a neutral point; a second capacitor coupling another side of the DC link to the neutral point; a plurality of phase legs, each phase leg including switches, each phase leg coupled to an AC node; a current sensor associated with each AC node; and a controller generating a PWM signal to control the switches, the controller generating a current zero sequence component in response to current sensed at each of the current sensors, the controller adjusting a modulation index signal in response to the current zero sequence component to produce the PWM signal.

PWM controlled neutral point clamped multilevel converter

A neutral point clamped, multilevel level converter including a DC voltage link having a positive rail and a negative rail; a phase leg coupled to an AC node, the phase leg having a first switch and a second switch in series between the negative rail and the AC node, the phase leg having a third switch and a fourth switch in series between the positive rail and the AC node; and a gate drive power supply having a charge pump section, the charge pump section generating a first gate drive voltage for the first switch and a second gate drive voltage for the second switch.

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Zagrebacka, Croatia

Marinko Kovacic