Patent ID: 9685898
Date: 2017-06-20
CPC Classifications: H02P

Claim:
1. An apparatus comprising: a switch module that, for each phase, selectively turns on a switch to connect an input power conductor connected to an alternating current (“AC”) voltage source to a motor in a sequence, wherein the switch for each phase is turned on for a portion of a cycle of a fundamental frequency of the AC voltage source, the portion comprising less than a full cycle of the fundamental frequency; a source phase module that determines a phase of the AC voltage source; a back-EMF phase module that determines a phase of a back-electromotive force (“back-EMF”) of the motor; a torque module that determines when a phase difference between the phase of the AC voltage source and the phase of the back-EMF is within a phase range indicative of a positive motor torque; and a pulse module that enables turning on of the switch for each phase of the motor in response to the phase difference comprising a phase within the phase range and disables turning on of the switch for each phase of the motor in response to the phase difference comprising a phase not in the phase range, wherein at least a portion of the switch module, the source phase module, the back-EMF phase module, the torque module, and the pulse module comprise one or more of hardware and executable code, the executable code stored on one or more non-transitory computer readable storage media.