Abstract: A power supply for an HVAC/R system is configured to provide back-up power functionality for situations when the main source of power fails. The power supply includes a DC power bus which receives power from the main source of power as well as a back up source. When the main source fails the back up source provides power to the DC power bus. Connected to the DC power bus is a variable frequency drive power supply (VFD). The VFD is configured to provide power to the components of the HVAC/R system based on power received from the DC power bus.

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.

Abstract: A fuel-powered engine is provided to drive a mobile air conditioning or refrigeration unit such as a portable chiller, a container refrigeration unit, a portable packaged system, a transport tractor-trailer or truck refrigeration unit, etc. A control rapidly changes the engine speed between the predefined set of discreet engine speeds to precisely adjust the capacity of the refrigerant system. If the engine operates only at a single speed, then the control cycles the engine between this operating speed and a zero speed (the engine is shut off). If the engine can operate at multiple discreet speeds, then the control can cycle the engine between any of these speeds (including a zero speed). When a lower capacity is desirable, the engine operates for a longer time interval at a lower speed, and when a higher capacity is desirable, the engine operates for a longer period of time at a higher speed. The cycle rate is selected to control the comfort (e.g.

Abstract: A motor controlling method and apparatus of an air conditioner are disclosed. It is checked whether or not an operation frequency of a compressor motor is the same as or greater than a certain frequency and it is also checked whether or not a detected velocity of a fan motor is the same as or lower than a certain velocity during a certain time period. If the operation frequency is the same as or greater than the certain frequency and the detected velocity is the same as or lower than the certain velocity during a certain time period, the compressor motor is temporarily stopped. Because the compressor motor operates according to operational conditions of the fan motor, an overload can be prevented.

Abstract: A universal control panel for controlling operation of a cooling component. The universal control panel may have a variable frequency drive (VFD) that incorporates an input voltage and frequency sensing circuit; and logic, memory and communications circuits. The VFD accepts a plurality of differing input signals, analyzes the input signals and generates an output signal having a desired voltage and frequency to provide real time control over an electrical component operably associated with the cooling component. The VFD controls the cooling component in relation to changes in at least one of sensed pressure and a sensed temperature of a fluid, to dampen response of the electrical component, to thus achieve more efficient use of the cooling component being used to cool the fluid.

Abstract: An HVAC/R system is configured with power storage for power back-up to maintain substantially uninterrupted power in the case of a main power failure. The power back-up system has a DC power source configured to be recharged, and provides power to the HVAC/R components.

Abstract: In a refrigeration cycle device in which a compressor is driven by power transmitted from an engine, a torque limiter is adapted to interrupt a transmission of the power from the engine to the compressor when a torque transmitted from the engine to the compressor becomes a predetermined value. A control unit is adapted to determine whether the transmission of the power from the engine to the compressor is interrupted by the torque limiter by determining whether a deviation of a refrigerant discharge pressure of the compressor is below a predetermined pressure when the control unit commands the compressor to change the refrigerant discharge flow amount of the compressor. Thus, the control unit can determine whether the torque limiter interrupts the transmission of power from the engine to the compressor without, using a compressor revolution sensor.

Abstract: An electronic microprocessor-based control system for a refrigerator is provided having refrigeration components including a compressor, a condenser, a condenser fan, an evaporator, a variable speed evaporator fan. Multiple temperature sensors are provided to communicate with the electronic microprocessor-based electronic control system. The electronic microprocessor-based control system controls the operation of both the refrigeration and non-refrigeration components based on information provided by the multiple temperature sensors.

Abstract: An electric vehicle includes a control unit having overcurrent generation judgment unit, inverter selection unit, and inverter drive control unit. The overcurrent generation judgment unit judges whether an overcurrent is generated in an inverter for generation or an inverter for travel. When an overcurrent is generated in one of the inverters, the inverter selection unit selects the other inverter to be driven. The inverter drive control unit stops the driving of the one inverter and drives the other inverter to drive a travel motor or a generator.

Abstract: When cooling operation or dehumidifying operation is started, a blower fan for an evaporator and an exhaust fan for a condenser are driven at an initial rotational number. A compressor is driven at a fixed rotational number. Due to load variation, an operating current supplied from a power source is changed. When the operating current exceeds a reference value, the rotational number of the blower fan is gradually reduced. When an endothermic quantity by the evaporator decreases, a temperature of a gas refrigerant flowing through the evaporator is lowered. Since the load applied on the compressor is reduced, the operating current decreases. In this way, when the compressor is loaded, the operating current increased, however, by controlling operation of the fans as described above, it is possible to prevent that the power source is shut off due to overcurrent and operation is stopped.

Abstract: A cooling apparatus such as a refrigerator includes a refrigeration cycle including a compressor driven by an electric motor, a condenser, a throttle valve and an evaporator, a first physical amount detector capable of detecting a physical quantity representing a temperature of an object to be cooled by the cooling operation of the evaporator, a temperature control device capable of controlling a rotating speed of the motor based on the physical quantity detected by the first physical quantity detector so that the object is cooled approximately to a target temperature, a second physical quantity detector capable of detecting a physical quantity corresponding to a performance margin of the refrigeration cycle, and a rotating speed limiter capable of limiting the rotating speed of the motor to or below a predetermined speed based on a physical quantity detected by the second physical quantity detector.

Abstract: A linear compressor control system includes an electronic circuit controlling an electric motor that drive a piston of the compressor, such that the motor is operated intermittently with an on-time (tL) and an off-time (tD) to keep the compression capacity of the compressor substantially constant. The compressor is associated with a closed cooling circuit having an evaporator and a condenser. The off-time (tD) is shorter than the time necessary for the evaporation pressure (PE) in the evaporator and the condensation pressure (Pc) in the condenser to equalize each other after the compressor has been turned off.

Abstract: A refrigerant system (10, 100, 200) is provided with a power control system (30, 130, 230). The power control system adjusts the speed of the motors driving the refrigerant system components such as a compressor, a fan or a pump via a variable speed device (75, 175, 275) or bypasses the variable speed device (75, 175, 275) for normal operating speeds. A single power control system may be provided for the entire refrigerant system or each component may be independently controlled.

Abstract: The invention relates to a control method and system comprising an electronic control unit (11) controlling the electric current power supply from an electric power source to a motor-compressor arrangement (12, 13); the electronic control unit comprises a conversion means which is connected to an inversion means (15) to supply the voltage demanded by the motor (12). A PWM pulse width regulator (16) generates the switching signals for all the switching elements of the unit (11) relating to said demanded voltage.

Abstract: A scroll compressor is provided with a multiple-speed motor. A control selects a speed for operating the motor, along with selecting between several available options for the system capacity adjustment to meet external load demands in a most efficient and reliable manner. The disclosed embodiment includes an economizer circuit, an unloader function, and an optional suction modulation valve. By utilizing each of these features in combination with the multi-speed motor for the compressor, the present invention is better able to tailor provided capacity to desired capacity.

Abstract: The present invention discloses a frequency variable compressor, including a shell defining an airtight space, an accumulator temporarily storing refrigerant before introducing the refrigerant into the shell, a first compression mechanism unit positioned in the shell, including a rolling piston, a cylinder, a refrigerant suction hole, a refrigerant discharge hole and a vane, and compressing refrigerant, a second compression mechanism unit positioned in the shell, including a rolling piston, a cylinder, a refrigerant suction hole, a refrigerant discharge hole and a vane, and compressing refrigerant, a frequency variable motor positioned in the shell and transferring power to the rolling pistons of the first and second compression mechanism units through a rotating shaft, and a valve controlling the flow of the refrigerant such that the first and second compression mechanism units compress the refrigerant by a twin rotary compressor type or a 2-stage rotary compressor type.

Abstract: A compressor inlet pressure estimation apparatus for a refrigeration cycle system is disclosed. An electronic control unit 14 uses Tefin_lag(N) as an actual corrected temperature Tefin_AD(N) during a period Tp1 included in the timing t1 to t2. During a period Tp2 included in the timing t1 to t2, Tefin_fwd(N) is used as the actual corrected temperature Tefin_AD(N). Thus, a highly accurate corrected temperature Tefin_AD(N) can be determined over the on period (t1 to t2) of a compressor 2. In addition, Tefin_fwd(N) is used as the actual corrected temperature Tefin_AD(N) during the off period (t2 to 3) of the compressor 2. As a result, a highly accurate corrected temperature Tefin_AD(N) can be determined over the whole period including the on and off periods of the compressor 2. In this way, a highly accurate estimated value Ps_es(N) of the refrigerant inlet pressure of the compressor 2 can be determined.

Abstract: An automotive climate control system includes an evaporator, a variable speed compressor and a controller. The controller is configured to periodically alter a previous target evaporator temperature at a selected rate to generate a current target evaporator temperature, select a target compressor speed based on a difference between an actual evaporator temperature and the current target evaporator temperature, and command the compressor to operate at the target compressor speed.

Abstract: To reduce a leakage current when a motor for driving a compressor is energized, with the compressor unoperated. Setting the carrier frequency of an inverter at a value lower than that used during normal operation to cause phase interruption electrification of the motor.

Abstract: A method is provided for operating a refrigerant vapor compression system at substantially zero cooling capacity to facilitate tight temperature control within a climate-controlled environment associated with the refrigerant vapor compression system. The method includes the step of diverting substantially all refrigerant flow from the primary refrigerant flow circuit of the refrigerant vapor compression system at a first location downstream, with respect to refrigerant flow, of the heat rejection heat exchanger and upstream, with respect to refrigerant flow, of the evaporator refrigerant expansion device to reenter the primary refrigerant flow circuit at a second location downstream, with respect to refrigerant flow, of the evaporator and upstream, with respect to refrigerant flow, of the compression device.

Abstract: A method of controlling compressor for refrigerator and apparatus thereof are disclosed to control an operation of the compressor by optimum efficiency by changing freezing capacity of the compressor. The apparatus controls a rotation direction of the compressor installed in the refrigerator and changes the freezing capacity of the compressor in accordance with the rotation direction of the compressor, thereby effectively controlling the operation of the compressor.

Abstract: In a refrigeration unit including a variable performance compressor driven by an inverter motor, a sensor is configured to detect a physical amount corresponding to a refrigerant pressure on the high-pressure side of a refrigerant circuit. A measured value of the physical amount is compared with a first reference value corresponding to a first predetermined pressure of the refrigerant and a second reference value corresponding to a second predetermined pressure lower than the first predetermined pressure. A protective operation can start if the comparison result indicates that an actual refrigerant pressure is higher than the first predetermined pressure. The performance of the compressor can be gradually lowered if the comparison result indicates that an actual refrigerant pressure is between the first predetermined pressure and the second predetermined pressure.

Abstract: A system for controlling a heating and cooling system for use on a machine includes a condenser, an evaporator assembly, an electric motor driven compressor, and a master controller operable to determine and regulate an operational speed of the compressor. The master controller includes a plurality of control algorithms each receiving respective dynamic input information and outputting a respective controller speed request based upon the respective dynamic input information.

Abstract: A variable speed electric drive for use in refrigerant systems includes an electric motor for driving an associated component at a variable speed that is a function of an operating frequency of the motor; and a control for supplying alternating discrete drive frequencies to the electric motor to provide a continuously variable speed drive of the associated component. The control cycles the drive frequency to the electric motor among the at least two discrete frequencies so that the variable average resultant speed at which the associated component is driven is a function of a combination of the selected at least two discrete frequencies.

Abstract: A system is provided to control and operate a compressor to have two or more discrete output capacities in response to an outdoor temperature measurement. During operation of the compressor in an air conditioning or cooling mode, the compressor has a first output capacity in response to the outdoor temperature being greater than a first temperature setpoint and the compressor has a second output capacity in response to the outdoor temperature being less than a second temperature setpoint.

Abstract: A brushless direct current motor, includes a rotor which comprises a permanent magnet, a stator which comprises coils associated with a plurality of phases which form an electrical field for generating a torque by interaction with a magnetic field which is generated by the permanent magnet, and a load prevention part which is disposed inside the stator to electrically connect and disconnect the coils of the plurality of phases according to a temperature variation.

Abstract: A refrigerant cycle is provided with a multi-port compressor or compressor stages connected in series, and multiple condensers. A single evaporator communicates with the plurality of condensers. At least one of the plurality of condensers receives fully compressed refrigerant while the other condensers receive refrigerant at intermediate pressure. A control can optionally direct refrigerant to the condensers to achieve desired system heat rejection characteristics and operating conditions. One or multiple reheat coils may be associated with the evaporator and are arranged either in series or in parallel to provide a desired dehumidification function and reheat stages. One or several of the intermediate pressure condensers may be utilized for the reheat function as well.

Abstract: A system for controlling a centrifugal gas compressor (108) in an HVAC, refrigeration or liquid chiller system (100) in which flow of gas through the compressor is automatically controlled to maintain desired parameters within predetermined ranges so as to prevent stall and surge conditions within the system. A variable geometry diffuser (119) in the compressor controls the refrigerant gas flow at the discharge of the compressor impeller wheel (201). This arrangement reduces mass flow, decrease/eliminate flow-reducing stall, and increases the operating efficiency of the compressor at partial load conditions. The variable geometry diffuser control in combination with a variable speed drive (VSD) (120) increases the efficiency of the compressor at partial system loads, and eliminates the need for pre-rotation vanes at the inlet of the centrifugal compressor.

Abstract: A refrigeration system for controlling airflow around an air-cooled heat generating device having a plurality of components includes a refrigerant line split into second refrigerant lines, which are arranged in a parallel configuration with respect to each other. Evaporators are positioned along the second refrigerant lines and in the path of airflow supplied into the components or airflow exhausted from the components. The refrigeration system further includes a variable speed compressor and a controller for controlling the speed of the variable speed compressor. Furthermore, the refrigeration system includes a temperature sensor configured to transmit signals related to a detected temperature to the controller, and the controller is configured to vary the speed of the variable speed compressor based upon the detected temperature.

Abstract: A system and method includes a compressor operable in a refrigeration circuit and including a motor, a current sensor detecting current supplied to the motor, a discharge line temperature sensor detecting discharge line temperature of the compressor, and processing circuitry receiving current data from the current sensor and discharge line temperature data from the discharge line temperature sensor and processing the current data and the discharge line temperature data to determine a capacity of the refrigeration circuit.

Abstract: The present invention provides a hot water supply apparatus capable of reducing energy consumption. That is, except during operation of heating water, when a detection temperature of a temperature sensor becomes equal to or lower than a set temperature, a circulating pump is operated and a compressor is operated at a second operating frequency having a lower frequency than a first operating frequency, thereby the compressor does not have to be repeatedly operated and stopped, and can be continuously operated in a state of reduced heating power.

Abstract: A variable speed drive is provided for a compressor in a refrigerant system. When a low load situation has been determined by the refrigerant system controls, the variable speed drive moves the compressor to a lower speed mode of operation. In this case, if a speed is so low that it cannot ensure adequate oil lubrication of the compressor elements, then the motor speed is periodically increased to a level that will ensure proper lubrication. In this manner, a variable speed drive compressor can be operated at an extremely low speed to precisely match load demand on a refrigerant system. The invention can be extended beyond refrigerant system applications and to any oil-lubricated compressors whose lubrication is speed dependant.

Abstract: An automotive climate control system includes an evaporator, a variable speed compressor and a controller. The controller is configured to periodically alter a previous target evaporator temperature at a selected rate to generate a current target evaporator temperature, select a target compressor speed based on a difference between an actual evaporator temperature and the current target evaporator temperature, and command the compressor to operate at the target compressor speed.

Abstract: A refrigerant cycle device includes a compressor driven by a vehicle engine for drawing and compressing gas refrigerant from an evaporator, a variable displacement mechanism which varies a discharge capacity of the compressor based on a control value from an exterior to approach a suction pressure of the compressor to a predetermined suction pressure, and a control unit for controlling the discharge capacity of the compressor. The control unit includes a determining part for determining an accelerating state of the vehicle engine, a detecting member which detects a thermal load of the evaporator, a setting part for setting a minimum control value in accordance with the thermal load, and a controlling part. The controlling part reduces the control value to the minimum control value and returns the reduced control value to a control value before the reducing, when the determining means determines an accelerating state of the vehicle engine.

Abstract: Variable speed drives are utilized in refrigerant systems to operate motors of the system components at varying speeds, typically for the purposes of capacity adjustment, efficiency enhancement, reliability improvement or power consumption limitation. However, variable speed controls are expensive. The present invention offers flexibility to utilize a variable speed drive to provide variable speed functionality between compressor and fans (or other rotating components having electric motors) within a refrigerant system depending on operational and environmental conditions and external load demands. The switching device switches the variable speed drive between component motors as indicated by a control for the refrigerant system.

Abstract: A vehicle compressor is controlled based on an environment parameter and a vehicle status parameter. In at least one embodiment, a temperature control system for a vehicle including an engine is provided. The system includes a compressor having a target operating speed. The system also includes an environment sensor arrangement configured to sense an environment parameter and a vehicle status sensor arrangement configured to sense a vehicle status parameter. The system further includes a control module that determines a maximum operating speed of the compressor as a function of both the environment parameter and the vehicle status parameter. The control module limits an operating speed of the compressor to the maximum operating speed if the target operating speed is greater than the maximum operating speed.

Abstract: An apparatus and method for controlling an operation of a compressor are disclosed to enhance a compressor efficiency in each operation mode in operating a compressor in a power mode or power saving mode according to an external load. The apparatus for controlling an operation of a compressor, including: a controller that generates a control signal to select an operation mode of the compressor according to an operation load of the compressor; a compressor motor that includes a main coil and a sub-coil and is driven in one of a plurality of operation modes according to a control signal of the controller; and a power supply unit that applies power via capacitors each having a different capacitance to the sub-coil of the compressor motor according to a control signal of the controller.

Abstract: An air conditioner for a vehicle comprises a refrigeration cycle including a variable displacement compressor for refrigerant which uses an engine as a drive source, a condenser, and an evaporator, a displacement adjustment means for outputting a displacement control signal to the compressor, and a compressor torque calculation means for calculating the torque of the compressor. The compressor torque calculation means includes at least two torque estimation means of a saturation region torque estimation means corresponding to a case where the compressor is driven at a maximum discharge displacement and a displacement control region torque estimation means corresponding to a case where it is driven at a discharge displacement other than the maximum discharge displacement, and also includes a correction means for correcting the calculation of the torque of the compressor when a change in engine rotational speed greater than a set value is detected.

Abstract: Systems and methods for improved Variable Speed Drives are provided. One embodiment relates to apparatus for common mode and differential mode filtering for motor or compressor bearing protection when operating with Variable Speed Drives, including conducted EMI/RFI input power mains mitigation. Another embodiment relates to a method to extend the synchronous operation of an active converter to the AC mains voltage during complete line dropout. Another embodiment relates to an active converter-based Variable Speed Drive system with Improved Full Speed Efficiency. Another embodiment relates to a liquid- or refrigerant-cooled inductor. The liquid- or refrigerant-cooled inductor may be used in any application where liquid or refrigerant cooling is available and a reduction in size and weight of a magnetic component is desired.

Abstract: A capacity control algorithm for a multiple compressor liquid chiller system is provided wherein the speed and number of compressors in operation are controlled in order to obtain a leaving liquid temperature setpoint. In response to an increase in the load in the chiller system, the algorithm determines if a compressor should be started and adjusts the operating speed of all operating compressors when an additional compressor is started. In response to a decrease in the load in the chiller system with multiple compressors operating, the algorithm determines if a compressor should be de-energized and adjusts the operating speed of all remaining operating compressors when a compressor is de-energized.

Abstract: An air handling system for cooling and/or heating a room includes a sleep mode. The system includes a fan assembly to transport air from the system into the room. A user interface transmits a sleep mode signal upon activation of the sleep mode by a user. A control unit controls the climate control unit to gradually change an ambient temperature in the room over a predetermined period of time in response to the sleep mode signal transmitted by the user interface. Further, the fan assembly has a substantially continuously adjustable speed within a range of speeds defined by a predetermined upper limit and a predetermined lower limit. The control unit adjusts the speed of the fan assembly according to a desired speed of the fan assembly input via the user interface. A multi-position switch defines the predetermined upper and lower limits.

Abstract: In controlled cooling operation, data on the controlled cooling operation characteristics is read out from a memory and compared with a drop degree of an inside temperature actually measured by an inside temperature sensor 46, and a cooling device is operated so that the inside temperature drops following a temperature curve stored in advance. A state where the inside temperature is higher than the set temperature by 7 K or more lasts for 15 minutes, for example, the cooling capacity by the cooling device is increased than the cooling capacity based on control of a controlled operation controller so that even if a door 17 is frequently opened/closed and the inside temperature tends to gradually rise, it can be detected at an early stage and kept close to the set temperature.

Abstract: An air conditioner includes a fixed displacement-type first compression mechanism and a variable displacement-type second compression mechanism independent from each other in a refrigeration cycle, and further includes second compression mechanism displacement control means, compression mechanism operation switching control means, an evaporator for refrigerant, a condenser, a blower, evaporator temperature detection means, and evaporator target temperature calculation means. When the refrigeration cycle is operated only by the first compression mechanism, referring to a temperature (Teva) detected by the evaporator temperature detection means, a temperature (Toff) calculated by the evaporator target temperature calculation means and a predetermined value A, if a condition of Teva?Toff?A is satisfied, both compression mechanisms are operated simultaneously.

Abstract: Relatively constant temperatures are maintained in a space by varying the capacity of heating or cooling equipment. A proportional band is used to adjust capacity to compensate for changes in heating or cooling load, and the proportional band is adjusted to bring the actual temperature within the space closer to the set point temperature. Such an adjustment may be made by determining the difference between the present temperature and the set point temperature, and adjusting a floating temperature set point by a percentage (e.g., ten percent) of the difference. Such a process may be repeated, for example, at regular intervals, such as once per minute. As a result, the temperature within the space approaches (e.g., asymptotically) the set point temperature whether the heating or cooling load is high or low. Methods, systems, and apparatuses are contemplated, including HVAC units and controls, including for residential applications, including using variable-speed drives.

Abstract: A refrigerator is provided having a refrigeration system including a variable speed compressor, a condenser, a condenser fan, an evaporator, a variable speed evaporator fan. The refrigerator further includes multiple temperature sensors that communicate with an electronic microprocessor-based control system that in turn controls the operation of the refrigerator system based on the information provided by the multiple temperature sensors.

Abstract: A noise control method is provided for a cooling system having at least one refrigerant circuit. The refrigerant circuit includes a compressor, a condenser, at least one condenser fan, and an evaporator. Noise control is only performed periodically in response to requirements for reduced operation at predetermined times. The request for reduced noise triggers the commencement of the noise control method. The noise control method involves reducing the operating speed of the compressor, as well as reducing the operating speed of at least one condenser fan, to within a predetermined range of allowable reduced operating speeds. The noise control method temporarily overrides the ability of the cooling system to fully respond to increased cooling or heating demands.

Abstract: A variable speed control system is provided for use with a heat pump heating/cooling system having a variable speed compressor. The control system includes a remote transceiver, a second transceiver to communicate with the first transceiver, and an AC power module to communicate with the second transceiver. The AC power module further includes multiple current limiting devices and multiple temperature sensors and varies the output of the variable speed compressor by comparing the readings from the temperature sensors to a pre-determined temperature setting.

Abstract: A storing section stores data of a pull down cooling characteristic indicative of a time-varying mode of reduction in a target temperature drop. For example, when this is a linear function line, a target internal temperature drop degree takes a constant value, irrespective of an operating time. An actual temperature drop degree is computed on the basis of the detected internal temperature. The computed value is compared with a target value read from the storing section. When the computed value is less than the target value, a rotational speed of an inverter compressor is increased via an inverter circuit. When the computed value is larger than the target value, the rotational speed of the compressor is decreased. The speed increases and decreases are repeated so that pull down cooling is performed along the linear line.

Abstract: A refrigeration system for controlling airflow around an air-cooled heat generating device includes a variable speed compressor. The refrigeration system also includes evaporators positioned along a refrigerant line in a serial configuration with respect to each other and are positioned directly in at least one of the path of airflow supplied into the heat generating components and the path of airflow exhausted from the heat generated components. The refrigeration system further includes a controller and at least one temperature sensor. The temperature sensor is configured to transmit signals related to the detected temperature to the controller, and the controller is configured to vary the speed of the variable speed compressor based upon the signals received from the temperature sensor.

Abstract: A scroll compressor is provided with a multiple-speed motor. A control selects a speed for operating the motor, along with selecting between several available options for the system capacity adjustment to meet external load demands in a most efficient and reliable manner. The disclosed embodiment includes an economizer circuit, an unloader function, and an optional suction modulation valve. By utilizing each of these features in combination with the multi-speed motor for the compressor, the present invention is better able to tailor provided capacity to desired capacity.