Abstract: A separate-type air conditioner that can reduce the effect of voltage fluctuations in a commercial power supply (12) on a compressor (11), reduce material costs while maintaining vibrations of an outdoor unit (2) at low levels, and improve working efficiency during an assembly operation. The outdoor unit (2) includes a voltage correction circuit (14) to keep an output voltage to the compressor (11) constant (optimum) irrespective of the voltage fluctuations in the commercial power supply (12).

Abstract: A refrigeration/air conditioning system includes a compressor having a motor protector which stops the compressor's motor when it senses an out of specification condition. A diagnostic system of the refrigeration/air conditioning system monitors the status of the motor protector. The diagnostic system includes logic circuitry that diagnoses the type of problem the compressor or the system is having based upon the running times and status of the motor in conjunction with the times and status of the tripped motor protector. The diagnostic system also includes either a discharge pressure sensor or a condenser temperature sensor, an ambient air sensor and a voltage sensor. The sensors provide information to the diagnostic system which enables it to determine where a system fault has occurred.

Abstract: A separate-type air conditioner that can reduce the effect of voltage fluctuations in a commercial power supply (12) on a compressor (11), reduce material costs while maintaining vibrations of an outdoor unit (2) at low levels, and improve working efficiency during an assembly operation. The outdoor unit (2) includes a voltage correction circuit (14) to keep an output voltage to the compressor (11) constant (optimum) irrespective of the voltage fluctuations in the commercial power supply (12).

Abstract: An air-conditioner for use in an automotive vehicle, an engine of which is stopped every time the vehicle stops at an intersection, includes a usual refrigeration cycle having a main compressor driven by the engine and a sub-circuit having a sub-compressor driven by an electric motor. The sub-compressor is connected in parallel to the main compressor, and both compressors are alternately driven. Refrigerant mixed with lubricant circulating in the main refrigeration cycle is prevented from entering into the sub-circuit while the sub-compressor is not in operation by means of a piping structure of the sub-circuit. When the refrigerant enters into the sub-circuit, it is efficiently returned to the main refrigeration cycle by intermittently operating the sub-compressor while the main compressor is operating.

Abstract: Air conditioning systems (1) may include an air conditioning circuit (2) and an electrically driven compressor (C). The compressor may have a motor (M) that includes a rotor (12) and a stator (14). The rotor may be rotated by a magnetic force generated when current is supplied to the stator. A temperature sensor (22) may detect the temperature of the rotor or the ambient temperature when the rotor is started to be rotated. A current calculator (26) may calculate a demagnetization limit current of the rotor at the detected temperature. The calculated demagnetization limit current may be used for determining a current that will be supplied to the stator for a predetermined period. In the alternative, the supplied current may increase as the rotor temperature increases during the initial operation. Preferably, the current may be less than the demagnetization limit current and may be greater than a minimum current that is required to rotate the rotor.

Abstract: A solar powered vapor compression refrigeration system is made practicable with thermal storage and novel control techniques. In one embodiment, the refrigeration system includes a photovoltaic panel, a variable speed compressor, an insulated enclosure, and a thermal reservoir. The photovoltaic (PV) panel converts sunlight into DC (direct current) electrical power. The DC electrical power drives a compressor that circulates refrigerant through a vapor compression refrigeration loop to extract heat from the insulated enclosure. The thermal reservoir is situated inside the insulated enclosure and includes a phase change material. As heat is extracted from the insulated enclosure, the phase change material is frozen, and thereafter is able to act as a heat sink to maintain the temperature of the insulated enclosure in the absence of sunlight.

Abstract: An automobile air conditioner having a charging device for charging a power source capacitor preliminarily before driving a motor-driven compressor, which comprises a discharge circuit for discharging the electric charge in the capacitor through a power feeding device, and a controller for controlling the discharge by the discharge circuit. Further by comprising a cut-off detecting circuit for detecting when the battery is cut off, it is discharged automatically. Moreover, the voltage of the battery is converted, and supplied as a power source for the controller.

Abstract: A compressor includes a motor protector which stops the compressor's motor when it senses an out of specification condition. A diagnostic system monitors the status of the motor protector. The diagnostic system includes logic circuitry that diagnoses the type of problem the compressor is having based upon the running times and status of the motor in conjunction with the times and status of the motor protector.

Abstract: A solar powered vapor compression refrigeration system is made practicable with thermal storage and novel control techniques. In one embodiment, the refrigeration system includes a photovoltaic panel, a variable speed compressor, an insulated enclosure, and a thermal reservoir. The photovoltaic (PV) panel converts sunlight into DC (direct current) electrical power. The DC electrical power drives a compressor that circulates refrigerant through a vapor compression refrigeration loop to extract heat from the insulated enclosure. The thermal reservoir is situated inside the insulated enclosure and includes a phase change material. As heat is extracted from the insulated enclosure, the phase change material is frozen, and thereafter is able to act as a heat sink to maintain the temperature of the insulated enclosure in the absence of sunlight.

Abstract: Electronic circuitry provides protection for refrigeration machines by continuously monitoring supply voltage conditions and various other conditions. Information regarding abnormalities detected in the refrigeration machines or supply voltage is stored in a memory. The stored information may then be downloaded from the memory by a service technician. The electronic circuitry is universal and can therefore be used with various refrigeration machines. Further, the efficiency of a low temperature storage cabinet is enhanced by cycling the evaporator motor in comparison to a compressor percentage run time. Other factors are also considered in the running of the reach-in cabinet evaporator fan.

Abstract: It is an object of the present invention to provide an operation control method of an air-conditioning apparatus and an air-conditioning apparatus that prevent a plurality of air-conditioning apparatuses from simultaneously restarting upon their automatic recovery after a recovery of power and from stopping again due to a voltage drop. The air-conditioning apparatus of the present invention is provided with an automatic recovery control circuit (21) for deciding a delay time until a restart based on set data for deciding operation works of the air-conditioning apparatus or randomly, thereby to restart the air-conditioning apparatus with the decided delay time.

Abstract: A system and method for monitoring and controlling an electrically driven transport refrigeration unit under varying operating conditions while maintain the system generator within its electric current and temperature limitations is disclosed. Specifically, the present invention the management of generator power through the combined use of controls for a suction modulation valve (an “SMV”), for diesel engine speed control, and for electronic expansion valve (“EXV”) superheat settings.

Abstract: A data acquisition system and method includes monitoring a cooling system having a refrigerant compressor, evaporator, and condenser, and employs a number of sensors to monitor various operating parameters of the system. These operating parameters are provided to a computer, which stores predefined operating parameters for a plurality of cooling systems. The computer compares the provided operating parameters of the monitored cooling system with the predefined operating parameters to provide diagnostic results for the monitored cooling system and possible service procedures. If the computer does not recognize the monitored cooling system identifier, a connection is made to a master computer in order look up the predefined operating parameters in a master data base.

Abstract: A clutch of the compressor is selectively engaged and disengaged by a coaction of an engine ECU and an air-conditioning ECU. If an air-conditioning system operating switch is detected as being turned on after a startup of an engine is detected, the clutch is changed from an off-state to an on-state to actuate the compressor to discharge a liquid refrigerant therefrom on the condition that an engine coolant temperature is higher than a reference engine coolant temperature. When the engine coolant temperature is higher than the reference engine coolant temperature, e.g., 40° C., the liquid refrigerant stored in the compressor is discharged of its own accord, and hence the amount of the liquid refrigerant stored in the compressor becomes small.

Abstract: The invention uses a variable speed drive (VSD) only on a range of capacities corresponding from zero to standard point conditions, and if conditions correspond to higher than rated point current, the VSD is disconnected and the compressor is connected directly on line. This approach allows using a smaller size VSD. At the same time, if there are several compressors operating in the same machine, only one VSD is needed. The VSD drives a first compressor from zero to the speed corresponding to the line frequency. Controls then switch the first compressor to direct on line (DOL) and disconnects the VSD from the first compressor. The VSD is then available to drive a second compressor. This process can be repeated through multiple compressors.

Abstract: The present invention balances power consumption reduction and a cooling in a vehicle air-conditioning system having a compressor selectively driven by a vehicle engine or a motor while the compressor is driven by the motor. At least one of a capacity of a blower and a capacity of a compressor arranged in a refrigeration cycle R while the compressor being driven by a motor is reduced in comparison to the capacity of the blower and the capacity of the compressor while the compressor being driven by a vehicle engine. Furthermore, while a cooling heat load of an evaporator is greater than a predetermined value, the capacity of the compressor is first reduced prior to reducing the capacity of the blower.

Abstract: A refrigerator, having a motor for driving a compressor, an inverter for controlling the operation of the motor, a converter responsive to AC to perform a boosting function to supply DC of variable voltage to the inverter, converter control means for controlling the converter so that a plurality of DC voltages are outputted thereby and inverter control means for controlling the inverter in pulse width modulation each of the plurality of voltages. The lowest voltage among the plurality of voltages being a voltage which turns off the boosting function of the converter.

Abstract: The invention concerns an electronic temperature controller, particularly for refrigeration appliances, with mains connections (3, 4) and an electronic circuit (1) having a power supply (7), a control unit and measuring and setting elements (9, 10, 11). The mains connections (3, 4) are connected with the power supply (7) via protective impedances (5, 6) consisting of at least two single impedances connected in series, and the electronic circuit is dimensioned for an operating current of maximum 0.35 mA (peak value) when connected to an AC mains and maximum 1 mA when connected to a DC mains. These values are doubled, when the electronic circuit has an earthing connection. This gives safety for the operator through shock-proof protection, which can be achieved at low cost and with small dimensions.

Abstract: The present invention relates to an apparatus and a method for protecting a motor of an inverter refrigerator comprising an OLP detect unit detecting operation of an OLP, and a power select unit selecting a power feed line in accordance with a detect signal inputted from the OLP detect unit, which is capable of driving properly the OLP in order to prevent damages on the motor due to overload or a rise in temperature of the motor with hysteresis of the OLP operation by preventing cutting off of the power feeding to a CPU when the OLP operates, accordingly the present invention can decrease claims from customers.

Abstract: An air conditioning system for use in a motor vehicle powered by an internal combustion engine is described. The system comprises an electric motor powered by a battery; a compressor arranged to be powered by at least one of the internal combustion engine and the electric motor; and a control unit that controls the driving of the compressor. The control unit is configured to execute driving the compressor by only the electric motor when the combustion engine is under an idling stop; restarting the combustion engine upon expiration of a first given time from the time when the idling stop has occurred, so that thereafter the compressor is driven by both the combustion engine and the electric motor; and stopping the driving of the compressor by the electric motor upon expiration of a second given time from the restarting of the combustion engine, so that thereafter the compressor is driven by only the combustion engine.

Abstract: A multi-stage driven type compressor pump driving system for air conditioning and refrigeration applications, a multi-stage driving structure other than a variable frequency stage-less driving structure to lower costs and improve electromagnetic compatibility (EMC) without loss of function relative to the variable frequency system.

Abstract: The motor power consumption and motor winding temperature are monitored and, responsive thereto, the flow of refrigerant to the motor is controlled so as to control the temperature of the motor. The motor power consumption in the primary control input because it anticipates cooling requirements whereas the motor temperature indicates current cooling requirements. The cooling flow may be provided in an on-off manner or there may be a constant flow portion with an on-off parallel cooling flow path.

Abstract: In a space cooling system having an evaporator in heat exchange relationship with a space to be cooled, a condenser external to the space, a compressor for circulating heat transfer fluid between the evaporator and condenser, an expansion valve for controlling the flow rate of heat transfer fluid through the evaporator, apparatus for automatically closing the expansion valve in response to a loss of electrical power to the system. The apparatus includes a storage capacitor for storing electrical energy when power is being supplied to the system, a voltage detector for detecting a loss of electrical power and a controller for controlling a step motor to close the expansion valve in response to a loss of system power. The capacitor automatically discharges in response to a power loss condition to supply power to the controller and step motor to enable the expansion valve to be closed. Therefore, refrigerant migration in the system, which can damage the compressor upon restart, is substantially inhibited.

Abstract: In a communication control system for an air conditioner including an outdoor unit, plural indoor units and control equipment such as a remote controller, etc. which is connected to each indoor unit through a communication line, data communication being carried out between each indoor unit and the control equipment through the communication line, each indoor unit is equipped with a communication control device having a power source circuit 59 to which a power source voltage is supplied from a main power source, a communication superposing circuit for superposing communication data on the power source voltage, a transistor 54 for ON/OFF-controlling the supply of the power source voltage from the main power source to the communication superposing circuit, and a polarity coincidence circuit 63A that passes the output of the communication superposing circuit therethrough to the communication line and depolarizes the power source voltage from the external.

Abstract: In a time and temperature controlled defrost cycle for a heat pump system, defrost cycles are controlled by two variables: elapsed time since the last defrost cycle, and the refrigerant temperature in the outdoor coil. The elapsed time variable for the first defrost cycle after power-up is set less than the elapsed time variable required for subsequent defrost cycles. Thus, the system is not vulnerable to planned cyclical power outages if the power outage cycle time is less than the elapsed time variable required between regular defrost cycles.

Abstract: A variable capacity compression type cooling system improves operating efficiency by modulating speed of the condenser pump motor and/or a cooling tower fan motor, in response to the loading level on the cooling apparatus. In contrast to known control strategies that rely on refrigerant gas pressure or temperature changes, the present system controls the heat rejection components in direct response to the current loading level on the cooling system. Cooling system loading is indicated, e.g,. by the current power ratio (percent of maximum) being utilized by the air conditioning compressor. The new strategy sets operation of the heat rejection components at a power setting that is a fixed ratio of the cooling system current power ratio (subject to limits). For a cooling tower, the control is applied to both the cooling tower fan(s) and the condenser pump(s). For small systems, a single variable-speed drive can be used for both the refrigerant compression device and the heat rejection component(s).

Abstract: An process and method for monitoring and limiting high voltage conditions in a transport refrigeration unit is disclosed. The system provides a microprocessor control which monitors the load, generator temperature and engine speed and compares it to an algorithm or map programmed into a controller for the unit. The map or algorithm preferably predicts voltage based upon load (amperage), generator temperature and engine speed. If the result of the monitored features predicts a voltage above preselected acceptable levels which are programmed into the controller, then the controller will drop the engine into low speed.

Abstract: A programmable electronic start-up delay for delaying the start-up of refrigeration units (10, 12, 14) for a user-programmable variable delay period. The delay permits a group of refrigeration units all powered by the same source (16) to be restarted at different time intervals after a power failure to prevent overloading of the power source or associated circuitry.

Abstract: A microprocessor based control system monitors and controls a heat pump water heater system and interfaces the water heating system with an external centralized control system. The microprocessor control system includes sensors, safety switches, device interface relays, user interface devices and precanned software to provide versatile monitoring and control over a heat pump type water heating system. The system generally involves a typical heat pump coupled with a domestic water heater, hot water retention tank or other body of water. The control system provides operational control over the heat pump to maintain the hot water stored in the domestic water heater in a predetermined setpoint and controls the use of electric resistance heating elements in the domestic water heater for added heating capacity for quick heat recovery type operation. The control system receives a centralized signal typically from a utility company to disable heat pump water heating operation during peak demand time periods.

Abstract: A system and method for monitoring and controlling an electrically driven transport refrigeration unit under varying operating conditions while maintain the system generator within its electric current and temperature limitations is disclosed. Specifically, the present invention the management of generator power through the combined use of controls for a suction modulation valve (an “SMV”), for diesel engine speed control, and for electronic expansion valve (“EXV”) superheat settings.

Abstract: An air conditioner system for vehicles has an exterior heat exchanger, which is used as an evaporator at the time of heating operation. A control unit monitors the heating operation and stores a defrost flag when the heating operation continues for a predetermined time period, e.g., 20 minutes, under a low exterior air temperature below a predetermined temperature, e.g., 5° C. When an electric vehicle is at rest after the heating operation to charge its secondary battery with an electric power from an external power source, the control unit first starts a defrosting operation and starts a charging operation of the secondary battery after the completion of the defrosting operation.

Abstract: When an air-conditioning is started, a determination is made as to whether a power relay is run so as to keep a compressor in a power-on state. When the power relay is in the power-on state, the running current of the power relay is detected. At this point, if the current value does not reach to a predetermined value, it is determined that the compressor is stopped in an exterior unit for protection.

Abstract: A mode of operation of an air-conditioning installation of a compression cycle type helicopter cabin or cockpit air-conditioning installation is characterized in that it includes a start-up sequence controlled by an inverter controlling the motor-compressor associated with a condenser equipped with a fan and during which the fan of the condenser is first powered up, after which the motor-compressor is powered up to start it at a low speed, after which the motor-compressor is operated under its normal conditions as a function of the cooling requirements of the installation. Other features concern the mode of powering the motor-compressor in accordance with various atmospheric and operating conditions.

Abstract: An system and method for monitoring and limiting high power and overheating engine conditions in a transport refrigeration unit is disclosed. The system provides a microprocessor control which monitor the engine coolant temperature to determine whether it exceeds a predetermined limit. If the engine coolant temperature exceeds that limit, the control sends a control signal which restricts or closes the suction modulation valve of the transport refrigeration system, restricting the mass flow rate of the system and thereby reducing the power draw on the engine. The system further provides a continued monitoring process for further restricting or closing the suction modulation valve in the event of continued high engine coolant temperatures, and for gradually opening the suction modulation valve and increasing the maximum current draw on the engine once the engine coolant temperature sinks below its predetermined limit.

Abstract: An air conditioner enables a user to input a desired monthly power cost for all electrical appliances, including the air conditioner. A microcomputer is able to calculate the accumulated power cost of operating the air conditioner for the month, as well as an expected power cost for operating all of the appliances. If the desired power cost for the month is below the expected power cost, the air conditioner is automatically operated in a power saving mode.

Abstract: A system and process for optimizing the power drawn on a transport refrigeration system under power limitation conditions is disclosed. The invention includes a microprocessor control which adjusts the desired superheat level for the system, thereby altering the expansion valve, thereby limiting the mass flow rate of refrigerant through the system without having a comparable drop in refrigeration capacity as would a similar actuation of the suction modulation valve.

Abstract: An operation control method for a refrigerator after a power-supply comeback due to a power-failure that performs a re-operation according to operation information stored before the power-failure.

Abstract: A programmable electronic start-up delay for delaying the start-up of refrigeration units (10, 12, 14) for a user-programmable variable delay period. The delay permits a group of refrigeration units all powered by the same source (16) to be restarted at different time intervals after a power failure to prevent overloading of the power source or associated circuitry.

Abstract: An air conditioner includes: a current detection unit for detecting a current value of alternating current power supplied from an alternating current power source; an indoor fan motor for exchanging heat of refrigerant for indoor heat; an outdoor fan motor for exchanging the heat of the refrigerant for outdoor heat; a compressor connected to an indoor heat exchanger and an outdoor heat exchanger where heat exchanging is carried out by the indoor fan motor and the outdoor fan motor respectively, for compressing the refrigerant; a refrigerant decompression unit connected to the indoor and outdoor heat exchangers for decompressing the refrigerant; a drive control unit receiving the alternating current power from the alternating current power source for controlling drive of the compressor; a voltage detection unit for detecting a voltage value supplied from the alternating current power source to the drive control unit; and a microcomputer receiving the current value detected by the current detection unit and the

Abstract: There is provided a demand control apparatus which is less attenuated in the wall and which can be installed even after the completion of construction of a new house. The present invention comprises a demand control unit for converting a restriction signal for restricting an electric current flowing to a circuit breaker so as not to exceed a target current value into a radio signal composed of a predetermined format and then transmitting the same, and a control unit for performing a modification in a way to reduce power consumption of the air conditioner when the restriction signal from the demand control unit is judged to be effective to coincide with the format.

Abstract: There is provided a controlling apparatus for an air conditioner, which comprises: an inverter circuit for feeding as an output a pseudo-sine wave from a switching signal obtained by comparison between a modulated wave and a carrier wave; a refrigeration cycle device which has a compressor driven by the pseudo-sine wave from the inverter circuit so that the modulated wave is adjusted according to a load of an air conditioner; and a correction device for correcting an amplitude of the modulated wave into a smaller one at a predetermined time when a rated voltage of the power source from the inverter circuit is larger than a rated voltage by a first predetermined value, and correcting the modulated wave into a larger one at a predetermined time when a rated voltage of the power source from the inverter circuit is smaller than the rated voltage by a second predetermined value.

Abstract: An process and method for monitoring and selectively implementing an operator selected economy mode in a transport refrigeration system is disclosed. The system includes a microprocessor control which, in response to operator selection of the economy mode, increases the base superheat setting, lowers the engine speed, limits the system current, and reduces the compressor capacity in order to optimize the fuel consumption of the system. The controller further monitors for the presence of an out of range alarm, and issues override commands reversing the superheat, compressor, current limit and engine speed economy mode settings at least until the out of range condition no longer exists.

Abstract: A method and system for controlling a refrigeration system is operative to reduce a system pressure of the refrigeration system. The system pressure is reduced to reduce a start-up current associated with a compressor motor of the refrigeration system. Another method and system for controlling a refrigeration system includes steps of performing an operation of the refrigeration system in accordance with at least one parameter, sensing an amount of energy utilized in at least a portion of the refrigeration system to perform the operation, and modifying the at least one parameter to reduce the amount of energy required to subsequently perform the operation.

Abstract: A wiring system for commercial refrigeration permits multiple refrigerated merchandisers to be wired on a single electrical circuit from a circuit breaker power source. The hardwiring of the system is done at the factory so that three-phase power connection of the merchandisers to a power source can be accomplished primarily by plug-in connectors at the installation site. Overcurrent protection of the merchandiser components can be provided where electrical power is branched off from a high current feeder line. The wiring system also permits power to be balanced among three phases of electrical power.

Abstract: When power is supplied to a refrigerator, the refrigerator control system performs one of two different automatic refrigerator temperature setting operations, depending upon whether it is determined that the power is or is not being supplied following a temporary power failure. That determination is made by sensing an internal refrigerator temperature (i.e., a temperature of the cooling compartment and/or the freezing compartment), and providing a reference temperature based upon a sensed external atmosphere temperature. If the refrigerator temperature is less than the reference temperature, then it is assumed that the power is being supplied following a temporary power failure and an appropriate refrigerator temperature setting operation is performed.

Abstract: A surge detection system for use in a fluid system having a load driven by a centrifugal compressor, the compressor being driven by an electric motor. The surge detection system comprises a means for sensing a differential pressure developed across the compressor and a means for sensing a current representing input power to the motor. The surge detection system further comprises a first computing means responsive to the differential pressure developed across the compressor for indicating when a valid surge is occurring in the compressor, and a second computing means responsive to the variable speed drive current for indicating when a valid surge is occurring in the compressor.

Abstract: An improved apparatus for controlling a refrigerator equipped with a linear compressor which is capable of achieving an optimum driving efficiency of the system irrespective of an operational condition of a refrigerator by providing the refrigerator with a linear compressor. The apparatus includes an operation ratio computation unit for computing an operation ratio of a compressor, a cooling capacity computation unit for computing a cooling capacity based on a stroke distance of a piston of the compressor, and a controller for maintaining a constant operation ratio by controlling the piston stroke distance in accordance with the operation ratio and the cooling capacity.

Abstract: To exercise control so that, when power is restored in the case of there having been a prower cut, the motor does not run simultaneously with other devices which reqire large amounts of power when starting to run. This invention there is provided improved freezer control unit, which exercise to ccntrol by providing power cut detector 10, which detects that the power source which drives freezer 5 has undergone a power cut, and stopping the signal of signal holding circuit 4, which outputs the `Run` signal, by the signal of this power cut detector 10 when a power cut occurs so that freezer 5 does not restart automatically when power is restored.

Abstract: A control apparatus of an air conditioner for stabilizing operating frequency of a compressor so as to prevent noise caused by hunting and to improve durability of the compressor. A frequency controller for controlling operating frequency of a compressor and a resistor for detecting an electric current flowing through the compressor are provided. A frequency reducer for reducing a frequency step of a compressor motor at a predetermined speed when a supply current of the compressor motor has reached a predetermined value and a frequency retainer for terminating frequency reducing operation of the frequency reducer when the supply current of the compressor motor has been decreased to the predetermined value and retaining a present frequency step until a predetermined period of time has elapsed are also provided.

Abstract: A highly efficient motor driver circuit of an electronic controller for linear cryogenic coolers operates directly from a variable power supply, such as a battery, without the need for the voltage regulator control circuit of the prior art. Elimination of the prior art voltage regulator ensures a higher efficiency motor driver circuit of the electronic controller. Both open-loop and closed-loop controllers electronically control the motor driver circuit. The open-loop controller protects against temperature sensor failure, and will limit maximum motor power as a function of system ambient temperature. The closed-loop controller regulates the temperature of the cold finger accurately to a preset value, using feedback from a temperature sensor along with a novel pulse-width modulation concept for modifying motor drive waveforms.