Abstract: Inventive concepts herein relate to mitigating phase current oscillations and vibrations in a spinning, lightly loaded three-phase electric motor. A motor starter can transition between various acceleration profiles defined by unique firing angles and/or firing angle rates of change. These transitions adjust the firing angle of thyristors, which directly manage each phase of a three-phase power supply to the motor. The motor start can identify when a motor has residual motion from prior operation and can modulate the firing angle and/or firing angle rate of change accordingly to reduce a duration of time that issues such as phase current oscillations or vibrations might occur.

Abstract: A multi-phase active filter includes a group of power cells electrically connected in a three-phase configuration, a precharging circuit, and a controller that controls the voltage delivered to the plurality of power cells. Each power cell includes an inverter having a pair of direct current (DC) terminals, at least one capacitor electrically connected in parallel with the inverter, and an energy dissipating circuit that is electrically connected in parallel with the inverter. The energy dissipating circuit of each power cell self-regulates DC voltage within the cell.

Abstract: A multi-phase active filter includes a group of power cells electrically connected in a three-phase configuration, a precharging circuit, and a controller that controls the voltage delivered to the plurality of power cells. Each power cell includes an inverter having a pair of direct current (DC) terminals, at least one capacitor electrically connected in parallel with the inverter, and an energy dissipating circuit that is electrically connected in parallel with the inverter. The energy dissipating circuit of each power cell self-regulates DC voltage within the cell.