A heat pump device includes: a compressor including a compression mechanism compressing a refrigerant and a motor driving the compression mechanism; an inverter unit applying a voltage for driving the motor; an inverter control unit generating a driving signal for driving the inverter unit; and temperature sensors detecting temperatures of the compressor, wherein the inverter control unit includes a normal operation mode in which a refrigerant is compressed by performing a normal operation of the compressor and a heating operation mode in which a heating operation of the compressor is performed by applying, to the motor, a high-frequency voltage, and in the heating operation mode, the inverter control unit determines an amplitude and a phase of a voltage command for generating the high-frequency voltage on a basis of a temperatures detected by the temperature sensors and a necessary amount of heat specified in advance.

A refrigerant circulation apparatus includes: a vehicle-interior air conditioning (2) that cools an interior of a vehicle; an on-vehicle battery cooler (3) that includes an evaporator for on-vehicle battery cooling (32) that cools an on-vehicle battery mounted on the vehicle; and an electric compressor (5) that compresses and supplies a refrigerant to at least one of the vehicle-interior air conditioning (2) and the on-vehicle battery cooling (3). The apparatus also includes: a temperature sensor (41) that detects a temperature of the electric compressor (5); a pressure sensor (42) that detects a pressure of the refrigerant compressed by the electric compressor (5); and a control unit (40) that restricts operation of the evaporator for on-vehicle battery cooling (32) to reduce load on the electric compressor (5) based on the temperature of the electric compressor (5) and the pressure of the refrigerant.

A refrigeration cycle apparatus includes: a refrigerant circuit including a compressor, a condenser, an expansion device, and an evaporator; a first detector provided to the compressor, and configured to detect a temperature of the compressor; a second detector provided between the compressor and the expansion device in the refrigerant circuit, and configured to detect one of a temperature of refrigerant and a pressure of the refrigerant; and a controller configured to control at least one of frequency of the compressor and an opening degree of the expansion device based on the temperature detected by the first detector and one of the temperature and the pressure detected by the second detector so as to maintain a concentration of a refrigerating machine oil dissolved in the refrigerant in the compressor and an oil level of the refrigerating machine oil in the compressor within respective predetermined ranges.

A refrigeration cycle device includes a refrigeration cycle formed by connecting a compressor, a condenser, an expansion valve and an evaporator to each other. As a refrigerant in the refrigeration cycle, a working fluid containing 1,1,2-trifluoroethylene (R1123) and difluoromethane (R32) is used. A degree of opening of the expansion valve is controlled such that the refrigerant has two phases at a suction portion of the compressor. With such a configuration, it is possible to provide highly reliable refrigeration cycle device by suppressing occurrence of a disproportionation reaction of R1123.

A split air conditioning system for conditioning a plurality of zones within a single living area of a building, that includes a single outdoor unit; a refrigerant flow pathway made up of a plurality of refrigerant conduits having a common refrigerant flow path portion and at least two divergent flow path portions, a first divergent flow path and a second divergent flow path and the first evaporator and second evaporator are in parallel with one another; at least one throttling device; a portioning device configured to selectively and proportionately regulate the flow of a refrigerant fluid to the first evaporator and the second evaporator, respectively where the compressor is configured to be capable of simultaneously driving both the first evaporator and the second evaporator at their full cooling capacity.

A motor driving apparatus and a home appliance including the same. The motor driving apparatus includes a temperature sensing unit to sense a compressor temperature, an inverter including a plurality of switching elements to convert a direct current (DC) voltage into an alternating current (AC) voltage and to supply AC voltage to a motor used to drive the compressor, and a controller to control the inverter. The controller performs control to apply motor preheating current for preheating of the motor during a first period before startup of the motor, and varies depending on the sensed temperature a time during which the motor preheating current is applied or a current application level. A reduction in power consumption during the preheating of the compressor is achieved.

A method of operating a refrigeration system that receives power from an electrical grid includes selectively operating at least one component of the refrigeration system in a first state. The method includes selectively detecting a fault event of the electrical grid in response to a concurrent (i) increase in amount of current drawn by the component and (ii) decrease in voltage of power received by the component. The method includes, in response to detecting the fault event, switching the component from the first state to a second state. The component consumes less power in the second state than in the first state. The method includes determining a first delay period. The method includes identifying a conclusion of the fault event. The method includes, in response to the conclusion of the fault event, waiting for the first delay period before switching the component back to the first state.

Disclosed herein is a method for failure prediction in an Air Cycle Machine (ACM). The method includes calculating a change in energy of an ACM airflow passing from an inlet of the ACM compressor to an outlet of the ACM compressor. The method may also include calculating a kinetic energy of the ACM compressor based on calculating the work of the ACM compressor on the ACM airflow as the ACM airflow passes through the ACM compressor, calculating the work of the ACM compressor based on the inlet temperature of the ACM airflow at the inlet of the ACM compressor, compressor pressure ratio of the ACM compressor, and a fluid property of the ACM airflow at the inlet of the ACM compressor. Additionally, the method can include calculating an ACM compressor efficiency as a ratio of the change in energy of the ACM airflow across the ACM compressor to the kinetic energy of the compressor. The method may further include predicting a failure state of the ACM compressor.

A method and system that describe collecting digital representation of observed variables of the operation of the vapor compression cycle over multiple instances of time and executing a constrained ensemble Kalman smoother for each instance of time to estimate the state variables of the vapor compression cycle for each instance of time. The constrained ensemble Kalman smoother updates the state variables over a sequence of time instances within a smoothing window by solving a series of constrained optimization problems in a range of a covariance, for which constraints are enforced for every variable in the smoothing window for every instance of the constrained optimization problems. The method and system further involve outputting, based on the estimates of the state variables, estimates of variables of the vapor compression cycle at each instance of time.

An example system for measuring emissions from a building includes a housing, a plurality of sensors arranged in the housing to detect concentrations of gas constituents in gas exiting the building, a gas flow sensor to detect a gas flow rate of the gas exiting the building, and a computing device to perform functions of calculating a total emissions of the particular gas constituent being tracked from a concentration of the particular gas constituent detected by the plurality of sensors and the gas flow rate, calculating an emission rate of the particular gas constituent being tracking, determining whether the total emissions and the emission rate of the particular gas constituent are within acceptable ranges, and based on the total emissions and the emission rate of the particular gas constituent being outside the acceptable ranges, outputting a prompt to a building computer system or operator indicating an alert.