Disclosed is a system and method for power line control of electrical fans. The system generates a sinusoidal wave using a crystal oscillator. Control information is added to the sinusoidal wave by routing the wave through a phase inversion circuit a predetermined intervals according to a protocol. The resulting control signal is sent on a power line. The control signal is received using a crystal filter, decoded and converted to executable instructions for controlling a fan motor.

A thermal management system is provided. The system includes a temperature sensor, a fan, an electronic circuit breaker (ECB) coupled to the fan to provide electric power to the fan. The system includes a controller coupled to the temperature sensor and the ECB, to direct the ECB to turn off the electric power to the fan responsive to detecting a temperature, from the temperature sensor less than a temperature threshold based on a temperature rating of the fan.

An apparatus for circulating air in a space using a fan, a sensor for sensing an ambient condition, and a user input for inputting a desired condition. A controller is configured for controlling the fan to operate substantially at a first fan speed for the desired condition, and controlling the fan to operate substantially at a second fan speed for the sensed ambient condition. Related methods are also disclosed.

A cartridge-based fan apparatus includes a cartridge component, wherein the cartridge component includes at least an airflow driver and at least a first spindle secured to a rotary device, a cartridge housing unit, wherein the cartridge housing unit includes a cartridge insertion chamber, a motor, and a drive element that mechanically couples the motor to the spindle when the cartridge is inserted in the cartridge insertion chamber, and a securing mechanism that secures the cartridge component in the cartridge insertion chamber.

A compressor for a heat transfer circuit includes a variable frequency drive (VFD), an electric motor that rotates a driveshaft, bearing(s) for supporting the driveshaft, a backup gas supply, and a power supply. During a utility power interruption, the backup gas supply operates utilizing DC electrical power generated by a back electromotive force of the electric motor. A method of operating an electric power supply system for a compressor includes operating in a utility power mode and operating in a backup power mode during a utility power interruption. In the utility power mode, AC electrical power is supplied from the VFD to the motor. In the backup power mode, DC electrical power generated in the VFD by a back electromotive force of the motor it used to operate a backup gas supply to supply compressed working fluid to gas bearing(s) of the compressor.

A method for controlling a fan in a fan start-up stage including a first time period and a second time period comprises the following steps of: during the first time period, continuously providing a first driving signal to drive the fan; and during the second time period, continuously providing a second driving signal to drive the fan; wherein, the signal value of the first driving signal gradually decreases until being equal to the signal value of the second driving signal. Wherein the signal value of the first driving signal non-linearly decreases, the signal value of the second driving signal is an unchanged value. Wherein, the first time period and the second time period are adjusted for a different fan but the sum of the first time period and the second time period is always the same. A fan is also disclosed.

A fluid control device includes a case including an internal space that is partitioned by a partition wall into an air blowing chamber and a control chamber. A dividing wall is disposed inside the air blowing chamber to partition an internal space of the air blowing chamber into a first air blowing chamber and a second air blowing chamber. A fan unit is housed in the second air blowing chamber. A differential pressure sensor senses a differential pressure between a pressure inside the first air blowing chamber and a pressure inside the second air blowing chamber. A controller controls a fan based on the sensed differential pressure.

A bridge circuit includes a high-side transistor connected between a power supply terminal and an output terminal, and a low-side transistor connected between the output terminal and a ground terminal. A high-side pre-driver and a low-side pre-driver drive the high-side transistor and the low-side transistor. A first transistor is connected between the output terminal and the ground terminal in a manner to form the regenerative path parallel to the low-side transistor. In a regenerative state in which a current sinks from the output terminal, a regenerative control circuit controls the voltage of a control terminal of the first transistor in a manner that an output voltage of the output terminal approaches a target voltage higher than the power supply voltage of the power supply terminal by a first voltage width.

A lightweight impeller is provided for use in a pressurised gas source for a CPAP or other breathing assistance apparatus. The impeller can be shroudless or otherwise lightweight.

A fan for use in agriculture which has a BLDC motor which allows for varying the speed of the fan to vary the airflow rate of the fan and vary the efficiency of the fan. A ventilation system for use in a livestock confinement building to maximize a rate of growth of the livestock. A process for maximizing the growth of livestock in a livestock confinement building by controlling the airflow in the livestock confinement building.