Abstract:
A system and method are provided including a system controller for a refrigeration or HVAC system having a compressor rack with a compressor and a condensing unit with a condenser fan. The system controller monitors and controls operation of the refrigeration or HVAC system. A rack controller monitors and controls operation of the compressor rack and determines compressor rack power consumption data. A condensing unit controller monitors and controls operation of the condensing unit and determines condensing unit power consumption data. The system controller receives the compressor rack power consumption data and the condensing unit power consumption data, determines a total power consumption of the refrigeration or HVAC system, determines a predicted power consumption or a benchmark power consumption for the refrigeration system, compares the total power consumption with the predicted power consumption or the benchmark power consumption, and generates an alert based on the comparison.
Abstract:
A drive controller for a motor of a compressor includes a drive circuit that applies voltages to windings of the motor. The drive controller includes a speed control module that controls the drive circuit to rotate the motor at a requested speed. The drive controller includes a speed determination module that generates the requested speed. The drive controller includes a defrost module that enables a defrost mode in response to a defrost command. While the defrost mode is enabled, the defrost module causes the speed determination module to (i) ramp the requested speed down from a speed demand to a defrost speed and (ii) maintain the requested speed at the defrost speed for a predetermined period of time.
Abstract:
A mixture of hydrocarbons in vapour phase is passed through a feed scrubber. Feed scrubber vapour discharged from the feed scrubber is passed to a compression suction scrubber, and a vaporous compressor feed stream from the compression suction scrubber is compressed in a compressor train. A compressed vaporous discharge stream from the train of compressors is de-superheated, and at least a portion of the de-superheated stream is passed to a condenser, wherein this portion of the de-superheated stream is at least partly condensed to form a pressurized and at least partially condensed mixture of hydrocarbons. A recycle portion is split off from the de-superheated hydrocarbon stream, and a recycle flow is established to the compressor train of via a surge recycle separator drum and the compression suction scrubber. Liquid constituents removed and drained from the recycle portion in the surge recycle separator drum are fed to the feed scrubber.
Abstract:
A domestic appliance (1) for washing goods (3) is provided, comprising a washing compartment (5) for receiving goods (3) to be washed, and a heat pump arrangement (7), adapted to heat washing liquid to be used in the washing compartment (5). The heat pump arrangement (7) comprises an evaporator (9) arranged to collect heat from ambient air, and a condenser (11) arranged to dissipate heat to the washing liquid to thereby heat the washing liquid. The heat pump arrangement (7) further comprises a variable speed fan (13) arranged to force the ambient air through the evaporator (9).
Abstract:
A refrigeration system for use in a refrigerator unit, the refrigeration system including a compressor having an ON state and an OFF state, a condenser, a temperature sensor, an evaporator, and an evaporator fan motor assembly. The evaporator fan motor assembly has an evaporator fan motor, a fan blade, and an internal control system. The internal control system of the evaporator fan motor assembly is adapted to sense the compressor state and is further adapted to operate the evaporator fan motor in response to the sensed compressor state. The refrigeration system may further include a condenser fan motor assembly. The condenser fan motor assembly has a condenser fan motor, a fan blade, and an internal control system. The internal control system of the condenser fan motor is adapted to sense the compressor state and is further adapted to operate the condenser fan motor in response to the sensed compressor state.
Abstract:
An ice maker for forming ice during a cooling cycle, the ice maker having a variable-speed compressor, a condenser, and an evaporator, wherein the variable-speed compressor, the condenser, and the evaporator are in fluid communication by one or more refrigerant lines. The ice maker further includes a freeze plate thermally coupled to the evaporator, a water pump, a sensing device for identifying a state of the cooling cycle, and a controller adapted to control the speed of the variable-speed compressor based on the identified state of the cooling cycle. The ice maker may also include a variable-speed condenser fan which may be controlled by the controller based on the identified state of the cooling cycle. Additionally, the water pump may be a variable-speed water pump which may be controlled by the controller based on the identified state of the cooling cycle.
Abstract:
A method of controlling a fan of a vapour compression system is disclosed. The vapour compression system comprises a compressor, a heat rejecting heat exchanger, e.g. in the form of a gas cooler or a condenser, an expansion device and an evaporator arranged in a refrigerant circuit. The fan is arranged to provide a secondary fluid flow across the heat rejecting heat exchanger, e.g. in the form of an air flow. The method comprises the steps of establishing a temperature, T 1 , of refrigerant leaving the heat rejecting heat exchanger, establishing a temperature, T 2 , of ambient air of the heat rejecting heat exchanger, and deriving a temperature difference, ΔΤ=Τ 1 -Τ 2 , between the temperature (T 1 ) of refrigerant leaving the heat rejecting heat exchanger and the temperature (T 2 ) of ambient air of the heat rejecting heat exchanger. The temperature difference, ΔΤ, is compared to a first threshold value and to a second threshold value, the second threshold value being smaller than or equal to the first threshold value, and the rotational speed of the fan is controlled on the basis of the comparing step. The method allows the electrical energy consumption of the fan to be reduced without risking instability of the vapour compression system.
Abstract:
A cascade heat pump system is configured with variable- speed compressors which allow operation at a high system coefficient of performance for a given thermal load. An electronic control module may be utilized to dynamically vary the speed of the compressors to achieve maximum energy efficiency. Variable- speed fans or blowers may also be used.