A server for a control system for cooling systems is disclosed. The server includes a memory device configured to store instructions and a processor communicatively coupled to the memory device and a plurality of cooling systems. Each of cooling systems includes a motor, a sensor, a local memory, and a microprocessor communicatively coupled to the motor, the sensor, the local memory. The microprocessor is configured to control operation of the motor according to settings defined by configuration data stored in the local memory. In response to reading the instructions, the processor is configured to receive, from the sensor of each of the cooling systems, first sensor data, generate first configuration data by executing a first algorithm on the first sensor data, and instruct the microprocessor of at least one cooling system to write the first configuration data to the local memory of the at least one cooling system.

A refrigeration system includes a compressor, a condenser, a heat transfer component, and a refrigerant loop arranged to allow a flow of a refrigerant fluid. The compressor, the condenser, and the heat transfer component are connected in the refrigerant loop. The system further includes a bypass path extending between an output side of the compressor in the refrigerant loop and an input side of the heat transfer component in the refrigerant loop. A bypass valve is connected in the bypass path. A control circuit is in communication with the bypass valve. The control circuit is configured to open the bypass valve to allow the refrigerant fluid to pass to the heat transfer component thereby increasing the refrigerant fluid provided to the heat transfer component and artificially increasing a load on the refrigeration system. Other examples refrigeration system and examples methods are also disclosed.

An EXV (electronic expansion valve) control system includes an EXV controller for controlling an EXV within the refrigerant loop of an HVAC system. The EXV controller implements a master control algorithm that includes a plurality of sub-control algorithms and an initial series of branching decision points to determine the current mode of operation and to execute select sub-control algorithms corresponding to the current mode of operation, while not executing the sub-control algorithms corresponding to the other modes of operation. The sub-control algorithms implement various combinations of PID (Proportional Integral Derivative) control and feed-forward control, the results of which can be mapped to specific control instructions for the EXV.

A method for operating an appliance motor includes receiving a target speed for the motor, obtaining a power limit for the motor, determining an inverter current limit based at least in part on the target speed and the power limit, determining an inverter output current to achieve the target speed, wherein the inverter output current is limited to the inverter current limit, and supplying the motor with the inverter output current.

Provide a technology that enables more appropriate determinations relating to the anomaly of a mechanical element in a rotating machine. The control device 40 according to an embodiment of the present disclosure includes the anomaly determining unit 403 configured to make a determination relating to an anomaly of a mechanical element of the compressor 10, based on an electrical feature amount of the compressor 10 that is electrically driven by the electric motor 20, wherein the electrical feature amount is a particular frequency component of a signal representing a physical amount that is correlated with a current of the electric motor 20 configured to drive the compressor 10, the particular frequency component is a predetermined positive integral multiple component of a rotational frequency of the compressor 10, and the anomaly determining unit 403 makes the determination relating to an anomaly of the mechanical element of the compressor 10, in consideration of a variation of a relationship between the anomaly of the mechanical element and the electrical feature amount of the compressor 10 (the electric motor 20), the variation being caused by a change in the rotational frequency of the compressor 10.

Variable volume ratio compressors may be controlled using a switching parameter based on compressor speed and suction density to improve the matching of compressor volume ratio to desired discharge conditions. Delay periods may be implemented in the determination of when to change volume ratio to control the frequency of changes to the volume ratio. The switching parameter may be a product of the compressor speed and suction density. The volume ratio of the compressor may be controlled by switching valves directing pressure to a piston of a variable volume ratio system of the compressor.

A method of operating a refrigeration cycle apparatus uses a compressor to compress a coolant. The compressed coolant is fed to a condenser for release of heat, the condensed coolant is later fed to a primary side of an internal heat exchanger for release of heat, and the cooled coolant is guided through an expansion device. The coolant expanded in the expansion device is fed to an evaporator for absorption of heat, the evaporated coolant is later fed to a secondary side of the internal heat exchanger for absorption of heat, and the heated coolant is fed to the compressor. For suction gas temperature control, an amount of heat transferred from the primary side to the secondary side of the internal heat exchanger is controlled with the aid of an additional expansion device arranged parallel to the heat exchanger and between the condenser and the evaporator.

A cold source unit is connectable to an indoor heat exchanger and is provided for a refrigerant circuit. The cold source unit includes: a compressor; an outdoor heat exchanger having a gas header; an oil return path through which refrigeration oil is returned from the gas header to the compressor; an oil return adjusting unit configured to adjust a flow rate of refrigeration oil flowing through the oil return path; and a controller configured to control the refrigerant circuit. The controller is configured to control the oil return adjusting unit to prevent refrigeration oil from flowing through the oil return path when the compressor is driven at a frequency equal to or higher than a threshold value, and control the oil return adjusting unit to allow the refrigeration oil to flow through the oil return path when the compressor is driven at a frequency lower than the threshold value.

A current estimating device that estimates a capacitor current of a high-voltage circuit for driving a motor, wherein the current estimating device calculates a voltage utilization rate using the input voltage of an inverter included in the high-voltage circuit and the speed of the motor, calculates a first constant by applying the voltage utilization rate to a predetermined first arithmetic expression, and calculates the capacitor current of an electrical condenser included in the high-voltage circuit by multiplying the first constant by a motor current effective value.

A refrigeration appliance includes at least one warm storage compartment and one cold storage compartment and a refrigeration device having at least two mutually parallel evaporators connected in series with a compressor, a condenser, and a shut-off valve between the condenser and evaporators in a refrigerant circuit so that each evaporator cools one storage compartment. An operating method for the refrigeration appliance includes the steps a) deciding whether a need for cooling has newly occurred in the warm storage compartment, and, if so, b) operating the compressor while the shut-off valve is closed to cause refrigerant to back up in the condenser, c) opening the shut-off valve and supplying the evaporator of the warm storage compartment with the backed up refrigerant. In step b) the mass flow rate through the compressor is estimated and the time for performing step c) is determined by using the estimated mass flow rate.