Abstract: An apparatus includes a switch module that selectively turns on a switch to connect an input power conductor connected to a voltage source to a motor in a sequence. The switch for each phase is turned on for a portion of a cycle of a fundamental frequency of the voltage source. A source phase module determines a phase of the AC voltage source, a back-EMF phase module determines a phase of a back-EMF of the motor, and a torque module 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. A pulse module enables the switches in response to the phase difference having a phase within the phase range and disables the switches in response to the phase difference having a phase not in the phase range.

Abstract: A motor controller includes a motor winding heater function. The motor controller applies a predefined current to one or more of the motor windings without the use of additional dedicated motor winding heater devices. The motor controller serves to control the operation of the motor, while the motor windings serve both as a heater at times and to produce torque at times.

Abstract: An apparatus for a quasi variable frequency motor controller is includes a DFC module that applies a first frequency to a motor as part of a discrete frequency control (“DFC”) method for motor starting. The first frequency includes a discrete frequency in a plurality of discrete frequencies of the DFC method and each discrete frequency includes a frequency lower than a fundamental frequency of an alternating current (“AC”) voltage source providing power to the motor. The apparatus includes a torque module that determines when motor torque generated by the motor reaches a negative torque threshold and a next frequency module that applies a second frequency to the motor in response to the torque module determining that the motor torque has reached the negative torque threshold. The second frequency is a next frequency in the DFC method.

Abstract: An apparatus includes a switch module that selectively turns on a switch to connect an input power conductor connected to a voltage source to a motor in a sequence. The switch for each phase is turned on for a portion of a cycle of a fundamental frequency of the voltage source. A source phase module determines a phase of the AC voltage source, a back-EMF phase module determines a phase of a back-EMF of the motor, and a torque module 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. A pulse module enables the switches in response to the phase difference having a phase within the phase range and disables the switches in response to the phase difference having a phase not in the phase range.

Abstract: An apparatus for a quasi variable frequency motor controller is includes a DFC module that applies a first frequency to a motor as part of a discrete frequency control (“DFC”) method for motor starting. The first frequency includes a discrete frequency in a plurality of discrete frequencies of the DFC method and each discrete frequency includes a frequency lower than a fundamental frequency of an alternating current (“AC”) voltage source providing power to the motor. The apparatus includes a torque module that determines when motor torque generated by the motor reaches a negative torque threshold and a next frequency module that applies a second frequency to the motor in response to the torque module determining that the motor torque has reached the negative torque threshold. The second frequency is a next frequency in the DFC method.

Abstract: A motor controller includes a motor winding heater function. The motor controller applies a predefined current to one or more of the motor windings without the use of additional dedicated motor winding heater devices. The motor controller serves to control the operation of the motor, while the motor windings serve both as a heater at times and to produce torque at times.