An electric motor assembly includes a stator, a rotor, a motor housing, a rotatable shaft, a radial fan, and an air scoop. The motor housing at least partly houses the stator and rotor and presents an exterior motor surface. The rotatable shaft is associated with the rotor for rotational movement therewith, with the rotatable shaft extending along a rotational axis. The radial fan is mounted on the rotatable shaft exteriorly of the motor housing and is rotatable with the shaft to direct airflow in a radially outward direction. The air scoop extends radially outwardly relative to the radial fan and axially to receive radial airflow from the radial fan and turn the airflow axially to flow along the exterior motor surface. The air scoop includes spaced apart axially extending airflow vanes to guide the airflow as the airflow is turned axially.

An electric motor assembly includes a stator, a rotor, a motor housing, a rotatable shaft, a radial fan, and an air scoop. The motor housing at least partly houses the stator and rotor and presents an exterior motor surface. The rotatable shaft is associated with the rotor for rotational movement therewith, with the rotatable shaft extending along a rotational axis. The radial fan is mounted on the rotatable shaft exteriorly of the motor housing and is rotatable with the shaft to direct airflow in a radially outward direction. The air scoop extends radially outwardly relative to the radial fan and axially to receive radial airflow from the radial fan and turn the airflow axially to flow along the exterior motor surface. The air scoop includes spaced apart axially extending airflow vanes to guide the airflow as the airflow is turned axially.

A magnetoelectric device capable of storing usable electrical energy includes an inductive servo control unit and a motor. The motor includes a rotor and three ferromagnetic-core coils disposed around the rotor. The inductive servo control unit executes individual phase control on the three-phase induction motor to magnetize the ferromagnetic-core coils with respective phases. When each of the ferromagnetic-core coils is demagnetized, it generates a current due to counter-electromotive force to charge a damping capacitor.

A magnetoelectric device capable of storing usable electrical energy includes an inductive servo control unit and a motor. The motor includes a rotor and three ferromagnetic-core coils disposed around the rotor. The inductive servo control unit executes individual phase control on the three-phase induction motor to magnetize the ferromagnetic-core coils with respective phases. When each of the ferromagnetic-core coils is demagnetized, it generates a current due to counter-electromotive force to charge a damping capacitor.

In an example, a system for determining a power factor of an electric device powered by an alternating current (AC) power is described. The system includes a current sensor configured to: (i) remotely sense, at a position external to the electric device, a magnetic field formed by the AC power in the electric device, and (ii) determine, based on the sensed magnetic field, a current of the AC power. The system also includes a voltage sensor configured to, at a position external to the electric device, remotely measure a voltage of the AC power. The system further includes a computing device communicatively coupled to the current sensor and the voltage sensor, the computing device being configured to: (i) determine a phase delay between the current and the voltage, and (ii) determine, based on the phase delay, a power factor of the electric device.

In an example, a system for determining a power factor of an electric device powered by an alternating current (AC) power is described. The system includes a current sensor configured to: (i) remotely sense, at a position external to the electric device, a magnetic field formed by the AC power in the electric device, and (ii) determine, based on the sensed magnetic field, a current of the AC power. The system also includes a voltage sensor configured to, at a position external to the electric device, remotely measure a voltage of the AC power. The system further includes a computing device communicatively coupled to the current sensor and the voltage sensor, the computing device being configured to: (i) determine a phase delay between the current and the voltage, and (ii) determine, based on the phase delay, a power factor of the electric device.

A drive circuit is provided and includes a rectification circuit, a buck converter, a first inverter, and a second inverter. The rectification circuit is configured to rectify a first AC voltage signal to generate a rectified voltage signal. The buck converter is configured to downconvert the rectified voltage signal to a DC voltage signal, wherein the DC voltage signal is supplied to a DC bus. The first inverter is configured to convert the DC voltage signal to a second AC voltage signal and supply the second AC voltage signal to a compressor motor. The second inverter is configured to convert the DC voltage signal to a third AC voltage signal and supply the third AC voltage signal to a condenser fan motor. Peak voltages of the second AC voltage signal and the third AC voltage signal are less than peak voltages of the first AC voltage signal.

A drive includes an inverter power circuit that applies power to an electric motor of a compressor from a direct current (DC) voltage bus. A power factor correction (PFC) circuit outputs power to the DC voltage bus based on input alternating current (AC) power. The PFC circuit includes: (i) a switch having a first terminal, a second terminal, and a control terminal; (ii) a driver that switches the switch between open and closed states based on a control signal; (iii) an inductor that charges and discharges based on switching of the switch; and (iv) a circuit that outputs a signal indicating whether the switch is in the open state or the closed state based on a voltage across the first and second terminals of the switch.

A circuit for driving a motor of a compressor includes a microcontroller, which includes an op-amp, a comparator, a first serial interface, and a first dedicated pin. The op-amp amplifies a value indicating current in a power factor correction converter, which includes a power switch. The comparator asserts a comparison signal in response to the amplified value exceeding a reference value. The comparison signal is output on the first dedicated pin. A programmable logic device (PLD) includes a second serial interface in communication with the first serial interface and a second dedicated pin. The comparison signal is received on the second dedicated pin and the PLD receives control messages from the microcontroller via the second serial interface. The PLD sets a value in an off-time register based on a control message from the microcontroller. The PLD controls the power switch according to the comparison signal and the off-time register.

A device for power factor correction can include a converter housing having an inner surface; a first converter substrate mounted on the inner surface of the converter housing; a second converter substrate mounted on another surface of first converter housing opposite to the inner surface; and a housing cover covering the first converter substrate and coupled to an upper surface of the converter housing, in which the second converter substrate includes a first surface having a first region including a source pad, and a second region including a drain pad spaced apart from the source pad, the source pad including a source pad extension portion extending into the second region; and a second surface including a heat dissipation pad for communicating heat from the source and drain pads to an outside of the device, in which the first region of the second converter substrate overlaps with the another surface of first converter housing, and the second region of the second converter substrate faces the housing cover without overlapping with the first converter substrate.