Abstract: An electrical machine includes a fan guard having a first air flow channel. A stator assembly is coupled to the fan guard and includes a stator yoke having a cylindrical outer surface and a stator pole shoe. The stator pole shoe includes a plurality of stator poles coupled to the stator yoke. The stator assembly includes a second air flow channel defined between the stator yoke and an adjacent pair of the stator poles. A rotor assembly is positioned inside the stator assembly. The rotor assembly includes a rotatable shaft and a rotor. The rotatable shaft defines a rotation axis. A control electronics board includes a plurality of heat making components and is enclosed in a housing having a vented base and a closure. The housing is coupled to the stator assembly opposite the fan guard. The vented base includes a plurality of vent openings opened toward the fan guard.

Abstract: A motor controller configured to be coupled to a motor and to a system controller is described. The motor controller includes a proportional-integral (PI) regulator coupled to a timer controller. The motor controller is configured to generate, by the PI regulator, a pulsed signal representing a reported speed of the motor. Additionally, the motor controller is configured to transmit the pulsed signal to the system controller, measure a time period that elapses for the motor to make a predefined number of revolutions, measure a number of pulses transmitted in the pulsed signal, and determine a measured speed of the motor from the time period. Further, the motor controller is configured to determine, by the PI regulator, a difference between the reported speed and the measured speed, and adjust, by the PI regulator, the pulsed signal based on the difference between the reported speed and the measured speed.

Abstract: A motor controller configured to be coupled to a motor and to a system controller is described. The motor controller includes a proportional-integral (PI) regulator coupled to a timer controller. The motor controller is configured to generate, by the PI regulator, a pulsed signal representing a reported speed of the motor. Additionally, the motor controller is configured to transmit the pulsed signal to the system controller, measure a time period that elapses for the motor to make a predefined number of revolutions, measure a number of pulses transmitted in the pulsed signal, and determine a measured speed of the motor from the time period. Further, the motor controller is configured to determine, by the PI regulator, a difference between the reported speed and the measured speed, and adjust, by the PI regulator, the pulsed signal based on the difference between the reported speed and the measured speed.

Abstract: An electrical machine includes a fan guard having a first air flow channel. A stator assembly is coupled to the fan guard and includes a stator yoke having a cylindrical outer surface and a stator pole shoe. The stator pole shoe includes a plurality of stator poles coupled to the stator yoke. The stator assembly includes a second air flow channel defined between the stator yoke and an adjacent pair of the stator poles. A rotor assembly is positioned inside the stator assembly. The rotor assembly includes a rotatable shaft and a rotor. The rotatable shaft defines a rotation axis. A control electronics board includes a plurality of heat making components and is enclosed in a housing having a vented base and a closure. The housing is coupled to the stator assembly opposite the fan guard. The vented base includes a plurality of vent openings opened toward the fan guard.

Abstract: A thermal protection device and methods for protecting a motor are described. The thermal protection device is electrically coupled between a power supply and a gate drive circuit for driving the motor. The thermal protection device is configured to disconnect the power supply from the gate drive circuit when a temperature measured by the thermal protection device exceeds a threshold temperature value.