A device for real-time self-diagnosis of a fan and a method are disclosed for detecting whether a fan body encounters an environment abnormal situation. The fan body includes a motor, a fan and a tachometer. The fan body further includes a microcontroller for receiving a speed signal of the tachometer and calculating a speed value of the fan, and detecting a current value of the motor during operation. The microcontroller can control the motor to drive the fan according to a monitoring period and a control signal transmitted from the control board, and can calculate a speed change amount according to the monitoring period, and can calculate a current change amount. When the speed change amount exceeds a speed change threshold and the current change amount exceeds a current change threshold for a period of time, the microcontroller generates an environmental anomaly signal.

A compressor control apparatus includes a rectifier configured to rectify AC power to DC power; an inverter including a plurality of switching elements, configured to convert the DC power into a three-phase voltage according to a pulse width modulation (PWM) signal applied to the plurality of switching elements; a motor configured to receive a three-phase current based on the three-phase voltage; a current detector configured to detect a sum of a first phase current, a second phase current, and a third phase current supplied to the motor; and a controller configured to differently determine a duty ratio of the PWM signal applied to each of the plurality of switching elements, and to determine the first phase current, the second phase current, and the third phase current, respectively, based on the determined duty ratio and the sum of the currents detected from the current detector.

A controller of a fan coupling device includes: an acquisition unit that acquires an acceleration parameter and a deviation parameter; a control unit that controls a regulation mechanism; a prediction unit that predicts that hunting occurs in the rotation speed of the fan, when an operating point of the fan expressed with the deviation parameter and the acceleration parameter belongs to a predicted region; and a restraining unit that executes, when the hunting is predicted to occur, a hunting restraining process of executing at least one of lowering an integral gain of a feedback control to be lower than when the hunting is not predicted to occur and increasing a derivative gain of the feedback control to be higher than when the hunting is not predicted to occur.

A motor control system providing at least seventeen speed settings using industry standard control signals and an industry standard five pin speed connector. One speed monitoring pin transmits an output signal for monitoring the speed of the motor, and four speed setting pins receive input signals for setting the speed. One of the speed setting pins receives and decodes two binary states and two frequency states, thereby providing a total of thirty-two speed settings. A non-regulated isolated winding is added to an internal transformer to provide an internal isolated flyback power supply for the motor, thereby liberating a pin on the industry standard five pin speed connector to provide the fourth speed setting input pin. Transmission circuitry is associated with the speed monitoring pin, and the non-regulated isolated winding is used to provide a direct current bias to the transmission circuitry.

Provided are a control method and apparatus for increasing the amount of a circulating refrigerant, and an air conditioner. The control method includes: when a refrigerating capacity need is equivalent to a heating capacity need in the operation of an air-conditioning system, determining whether the discharge temperature of a compressor is greater than a preset safety alert value; if the discharge temperature of the compressor is greater than the safety alert value, adjusting the frequency of a fan of an outdoor heat exchanger; and when the discharge temperature of the compressor is not greater than the safety alert value, controlling to stop the adjustment of the frequency of the fan, and maintaining the air-conditioning system to operate at the adjusted current frequency of the fan.

An air-conditioning apparatus includes a bypass pipe through which part of refrigerant discharged from a discharge port of a compressor flows. Heating components provided on a substrate of the controller include a first heating component and a second heating component that generates a smaller amount of heat than the first heating component. The first heating component is provided such that a longitudinal direction of the first heating component is parallel to a flow direction of the refrigerant in the bypass pipe, the longitudinal direction being a direction in which long sides of the first heating component extend. The second heating component is provided such that a widthwise direction of the second heating component is parallel to the flow direction of the refrigerant in the bypass pipe, the widthwise direction being a direction in which short sides of the second heating component extend.

A fan assembly and an inverter are provided. The fan assembly includes a fan guard, a fan body and a noise reduction mounting member. The fan body directly faces an air inlet, the air inlet is covered by a fan guard, and the noise reduction mounting member is arranged on the fan body, to provide a preset distance between the fan body and the fan guard, and the noise reduction mounting member is configured to mount the fan body on a to-be-mounted component in a buffered manner. The distance between the fan body and the fan guard can reach the preset distance due to the noise reduction mounting member. In addition, the noise reduction mounting member plays a vibration isolation function between the fan body and the to-be-mounted component, which improves the sound quality.

An air conditioner unit includes a variable speed compressor for circulating refrigerant through refrigeration loop and a controller configured to initiate an operating cycle, start a compressor transition timer, and determine an unfiltered compressor speed. The unfiltered compressor speed is fixed based on the selected operating mode until the compressor transition timer reaches a predetermined transition delay time, after which the unfiltered compressor speed is determined using a closed loop feedback control algorithm. The controller is further configured to operating the variable speed compressor at a target compressor speed that is modified from the unfiltered compressor speed based on the identification of a speed modification condition, such as a dehumidification deficiency a speed restriction, or the identification of one or more resonance avoidance zones.

The present disclosure generally relates refrigeration systems for temperature-controlled displays. For instance, one exemplary embodiment relates to a refrigeration system that includes a refrigeration circuit, a cooling circuit, a reclaim heat circuit, and a floor heating system. The refrigeration circuit includes a compressor driven by a brushless DC motor operable at multiple different speeds, a first heat exchanger, an expansion device, and a cooling unit in fluid communication using a first working fluid. The cooling unit is arranged to cool a temperature-controlled storage device. The cooling circuit includes a pump and a second heat exchanger in thermal communication with the first heat exchanger using a second working fluid such that the first heat exchanger is liquid-cooled by the second working fluid. The reclaim heat circuit is in fluid communication with the cooling circuit. The floor heating system is coupled to the heat reclaim circuit as a reclaim heat load.

A variable capacity screw compressor comprises a suction port, at least two screw rotors and a discharge port being configured in relation to a selected rotational speed that operates at least one screw rotor at an optimum peripheral velocity that is independent of a peripheral velocity of the at least one screw rotor at a synchronous motor rotational speed for a rated screw compressor capacity. A motor is configured to drive the at least one screw rotor at a rotational speed at a full-load capacity that is substantially greater than the synchronous motor rotational speed at the rated screw compressor capacity. A variable speed drive receives a command signal from a controller and generates a control signal that drives the motor at the selected rotational speed.