(19)
(11)EP 3 188 360 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
07.09.2022 Bulletin 2022/36

(21)Application number: 16200301.6

(22)Date of filing:  23.11.2016
(51)International Patent Classification (IPC): 
H02P 9/04(2006.01)
B60H 1/32(2006.01)
H02P 9/10(2006.01)
(52)Cooperative Patent Classification (CPC):
B60H 1/3232; H02P 9/04; H02P 9/48; B60H 1/3211; B60H 1/3226; B60H 2001/3292

(54)

CONTINUOUS VOLTAGE CONTROL OF A TRANSPORT REFRIGERATION SYSTEM

KONTINUIERLICHE SPANNUNGSSTEUERUNG EINER TRANSPORTKÜHLANLAGE

COMMANDE DE TENSION CONTINUE D'UN SYSTÈME DE DE TRANSPORT RÉFRIGÉRÉ


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 24.11.2015 US 201562259265 P

(43)Date of publication of application:
05.07.2017 Bulletin 2017/27

(73)Proprietor: Carrier Corporation
Farmington, CT 06034-4015 (US)

(72)Inventor:
  • FERGUSON, Benjamin Edward
    Syracuse, NY 13221 (US)

(74)Representative: Dehns 
St. Bride's House 10 Salisbury Square
London EC4Y 8JD
London EC4Y 8JD (GB)


(56)References cited: : 
WO-A1-2009/091396
US-A1- 2008 087 029
US-A- 5 504 417
US-A1- 2014 157 818
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description


    [0001] The embodiments herein generally relate to "all electric" transport refrigeration systems and the continuous voltage control of such systems.

    [0002] Refrigerated trucks and trailers are commonly used to transport perishable cargo, such as, for example, produce, meat, poultry, fish, dairy products, cut flowers, and other fresh or frozen perishable products. A transport refrigeration system is mounted to the truck or to the trailer in operative association with a cargo space defined within the truck or trailer for maintaining a controlled temperature environment within the cargo space.

    [0003] Conventionally, transport refrigeration systems used in connection with refrigerated trucks and refrigerated trailers include a transport refrigeration unit having a refrigerant compressor, a condenser with one or more associated condenser fans, an expansion device, and an evaporator with one or more associated evaporator fans, which are connected via appropriate refrigerant lines in a closed refrigerant flow circuit. Air or an air/ gas mixture is drawn from the interior volume of the cargo space by means of the evaporator fan(s) associated with the evaporator, passed through the airside of the evaporator in heat exchange relationship with refrigerant whereby the refrigerant absorbs heat from the air, thereby cooling the air. The cooled air is then supplied back to the cargo space.

    [0004] On commercially available transport refrigeration systems used in connection with refrigerated trucks and refrigerated trailers, the compressor, and typically other components of the transport refrigeration unit, must be powered during transit by a prime mover. In the case of refrigerated trailers, the prime mover typically comprises a diesel engine carried on and considered part of the transport refrigeration system. In mechanically driven transport refrigeration systems the compressor is driven by the diesel engine, either through a direct mechanical coupling or a belt drive, and other components, such as the condenser and evaporator fans are belt driven.

    [0005] An "all electric" transport refrigeration system for a refrigerated trailer application is also commercially available through Carrier Corporation headquartered in Farmington, Connecticut, USA. In the all electric transport refrigeration system, a prime mover, most commonly a diesel engine, carried on and considered part of the transport refrigeration system, drives an AC synchronous generator that generates AC power. The generated AC power is used to power an electric compressor motor for driving the refrigerant compressor of the transport refrigeration unit and also powering electric AC fan motors for driving the condenser and evaporator motors and electric heaters associated with the evaporator. For example, U.S. Pat. No. 6,223,546 discloses an all electric transport refrigeration system.

    [0006] US 2014/157818 discloses a method for control of a transport refrigeration system of the type defined in the preamble of claim 1 and a transport refrigeration system as defined in the preamble of claim 6.

    [0007] In some all electric transport refrigeration systems, when operating in a cold weather environment the prime mover will move to high speed to cool the cargo compartment, but if the generator voltage is over a max voltage limit the prime mover will move back down to low speed. The prime mover will cycle back to high speed when additional cooling is needed in the cargo compartment. The continually cycling of the prime mover between high speed and low speed is inefficient.

    [0008] According to a first aspect, the invention provides a method of operating a transport refrigeration system comprising: controlling, a first plurality of components of a refrigeration unit, wherein controlling comprises operating a prime mover and an electric generation device; and operating, the prime mover at a selected high speed; monitoring, a plurality of operating parameters of the refrigeration unit, wherein at least one of the operating parameters is at least one of a voltage of the electric generation device and a speed of the prime mover; comparing, the voltage of the electric generation device to a selected voltage; comparing, the speed of the prime mover to a selected speed; and characterized by: taking a corrective action when the voltage of the electric generation device exceeds a voltage limit for a first selected time period, wherein the corrective action comprises: operating the prime mover at a selected low speed and the controller initiating a continuous voltage control cycle mode, and wherein the continuous voltage control cycle comprises: operating the prime mover at an increasing rate of speed until the voltage of the electric generation device equals the selected voltage, and exiting the continuous voltage control cycle when the speed of the prime mover equals the selected high speed and the voltage of the electric generation device equals the selected voltage.

    [0009] In addition to one or more of the features described above, or as an alternative, further embodiments may include operating the prime mover at the selected high speed when the voltage of the electric generation device does not exceed a voltage limit for a first selected time period.

    [0010] In addition further embodiments may include taking a second corrective action when the speed of the prime mover is not equal to the selected high speed and the voltage of the electric generation device equals the selected voltage.

    [0011] In addition further embodiments may include reinitiating the continuous voltage control cycle when after a second selected time period, the voltage of the electric generation device is lower than the selected voltage.

    [0012] In addition further embodiments may include exiting the continuous voltage control cycle and continuing to operate the prime mover at the current speed when after a second selected time period, the voltage of the electric generation device is not lower than the selected voltage.

    [0013] According to a second aspect, the invention provides a transport refrigeration system comprising: a prime mover; an electric generation device powered by the prime mover and providing an electric output; a refrigeration unit electrically powered by the electric output of the electric generation device; and a controller in operative communication with the prime mover, the electric generation device, and the refrigeration unit, wherein the controller compares a voltage of the electric generation device to a selected voltage and a speed of the prime mover to a selected speed, and wherein the controller operates the prime mover at a selected high speed, characterized in that: the controller takes a corrective action when the voltage of the electric generation device exceeds a voltage limit for a first selected time period, wherein the corrective action comprises the controller operating the prime mover at a selected low speed and the controller initiating a continuous voltage control cycle mode, and wherein the continuous voltage control cycle comprises the controller operating the prime mover at an increasing rate of speed until the voltage of the electric generation device equals a selected voltage, and wherein the controller exits the continuous voltage control cycle when the speed of the prime mover equals the selected high speed and the voltage of the electric generation device equals the selected voltage.

    [0014] In addition further embodiments may include the controller continues to operate the prime mover at the selected high speed when the voltage of the electric generation device does not exceed a voltage limit for a first selected time period.

    [0015] In addition further embodiments may include the controller takes a second corrective action when the speed of the prime mover is not equal to the selected high speed and the voltage of the electric generation device equals the selected voltage.

    [0016] In addition further embodiments may include the controller reinitiates the continuous voltage control cycle when after a second selected time period, the voltage of the electric generation device is lower than the selected voltage.

    [0017] In addition further embodiments may include the controller exits the continuous voltage control cycle and continues to operate the prime mover at the current speed when after a second selected time period the voltage of the electric generation device is not lower than the selected voltage.

    [0018] The foregoing and other features and advantages of the invention are apparent from the following detailed description taken of a preferred embodiment, which is described by way of example only in conjunction with the accompanying drawings in which:

    FIG. 1 is a schematic illustration of a transport refrigeration system; and

    FIG. 2 is a flow diagram illustrating a method of operating a refrigeration system.



    [0019] Referring to FIG. 1, a transport refrigeration system 20 includes a refrigeration unit 22, an electric generation device 24, a prime mover 26 for driving the electric generation device 24, and a controller 30. The refrigeration unit 22 functions, under the control of the controller 30, to establish and regulate a desired product storage temperature within a refrigerated cargo space wherein a perishable product is stored during transport and to maintain the product storage temperature within a specified temperature range. The refrigerated cargo space may be the cargo box of a trailer, a truck, a seaboard shipping container or an intermodal container wherein perishable cargo, such as, for example, produce, meat, poultry, fish, dairy products, cut flowers, and other fresh or frozen perishable products, is stowed for transport.

    [0020] The transport refrigeration unit 22 includes a refrigerant compression device 32, a refrigerant heat rejection heat exchanger 34, an expansion device 36, and a refrigerant heat absorption heat exchanger 38 connected in refrigerant flow communication in a closed loop refrigerant circuit and arranged in a conventional refrigeration cycle. The refrigeration unit 22 also includes one or more fans 40 associated with the refrigerant heat rejection heat exchanger 34 and driven by fan motor(s) 42 and one or more fans 44 associated with the refrigerant heat absorption heat exchanger 38 and driven by fan motor(s) 46. The refrigeration unit 22 may also include an electric resistance heater 48 associated with the refrigerant heat absorption heat exchanger 38. It is to be understood that other components (not shown) may be incorporated into the refrigerant circuit as desired, including for example, but not limited to, a suction modulation valve, a receiver, a filter/dryer, an economizer circuit.

    [0021] The refrigerant heat rejection heat exchanger 34 may, for example, comprise one or more refrigerant conveying coiled tubes or one or more tube banks formed of a plurality of refrigerant conveying tubes extending between respective inlet and outlet manifolds. The fan(s) 40 are operative to pass air, typically ambient air, across the tubes of the refrigerant heat rejection heat exchanger 34 to cool refrigerant vapor passing through the tubes. The refrigerant heat rejection heat exchanger 34 may operate either as a refrigerant condenser, such as if the refrigeration unit 22 is operating in a subcritical refrigerant cycle or as a refrigerant gas cooler, such as if the refrigeration unit 22 is operating in a transcritical cycle.

    [0022] The refrigerant heat absorption heat exchanger 38 may, for example, also comprise one or more refrigerant conveying coiled tubes or one or more tube banks formed of a plurality of refrigerant conveying tubes extending between respective inlet and outlet manifolds. The fan(s) 44 are operative to pass air drawn from the temperature controlled cargo box across the tubes of the refrigerant heat absorption heat exchanger 38 to heat and evaporate refrigerant liquid passing through the tubes and cool the air. The air cooled in traversing the refrigerant heat rejection heat exchanger 38 is supplied back to the temperature controlled cargo box. It is to be understood that the term "air" when used herein with reference to the atmosphere within the cargo box includes mixtures of air with other gases, such as for example, but not limited to, nitrogen or carbon dioxide, sometimes introduced into a refrigerated cargo box for transport of perishable produce.

    [0023] The refrigerant compression device 32 may comprise a single-stage or multiple-stage compressor such as, for example, a reciprocating compressor or a scroll compressor. The compression device 32 has a compression mechanism (not shown) driven by an electric motor 50. In an embodiment, the motor 50 may be disposed internally within the compressor with a drive shaft interconnected with a shaft of the compression mechanism, all sealed within a common housing of the compression device 32.

    [0024] The refrigeration system 20 also includes a controller 30 configured for controlling operation of the refrigeration system 20 including, but not limited to, operation of various components of the refrigerant unit 22 to provide and maintain a desired thermal environment within the cargo box of the truck or trailer, that is within the temperature controlled space in which a perishable product is stowed. The controller 30 may be an electronic controller including a microprocessor and an associated memory bank. The controller 30 controls operation of various components of the refrigerant unit 22, such as the refrigerant compression device 32 and its associated drive motor 50, the fan motors 42, 46 and the electric heater 48. The controller 30 may also be also to selectively operate the prime mover 26, typically through an electronic engine controller 54 operatively associated with the prime mover 26.

    [0025] The refrigeration unit 22 has a plurality of power demand loads, including, but not limited to, the compression device drive motor 50, the drive motor 42 for the fan 40 associated with the refrigerant heat rejection heat exchanger 34, and the drive motor 46 for the fan 44 associated with the refrigerant heat absorption heat exchanger 38. In the depicted embodiment, the electric resistance heater 48 also constitutes a power demand load. The electric resistance heater may be selectively operated by the controller 30 whenever a control temperature within the temperature controlled cargo box drops below a preset lower temperature limit, which may occur in a cold ambient environment. In such an event the controller 30 would activate the electric resistance heater 48 to heat air circulated over the electric resistance heater by the fan(s) 44 associated with the refrigerant heat absorption heat exchanger.

    [0026] The prime mover 26, which comprises an on-board fossil-fuel engine, most commonly a diesel engine, drives the electric generation device 24 that generates electrical power. The drive shaft of the engine drives the shaft of the electric generation device 24. In an electrically powered embodiment of the transport refrigeration unit 20, the electric generation device 24 may comprise a single on-board, engine driven AC generator configured to generate alternating current (AC) power including at least one AC voltage at one or more frequencies. In an embodiment, the electric generation device 24 may, for example, be a permanent magnet AC generator or a synchronous AC generator. In another embodiment, the electric generation device 24 may comprise a single on-board, engine driven DC generator configured to generate direct current (DC) power at at least one voltage. As each of the fan motors 42, 46 and the compression device drive motor 50 may be an AC motor or a DC motor, it is to be understood that various power converters 52, such as AC to DC rectifiers, DC to AC inverters, AC to AC voltage/frequency converters, and DC to DC voltage converters, may be employed in connection with the electric generation device 24 as appropriate.

    [0027] Current all-electric refrigeration units have a generator voltage limitation when operating in cold environments. On current systems, once the refrigeration unit has met all the system parameters, the unit will attempt to move the engine to high speed, but if the generator voltage is over a voltage limit for a short period, the unit will move back to low speed. The refrigeration system 20 has a voltage sensor 28 to sense the voltage of the electric generation device 24. During cold ambient operation, the refrigeration system 20 controls the speed of the prime mover 26 to maintain the output of the electric generation device 24 below a voltage limit. As the unit warms up and the voltage output of electric generation device 24 decreases, the speed of the prime mover 26 will be increased and remain at an increased level to boost the heating or cooling capability, instead of returning back to low speed. The prime mover 26 will maintain a speed such that a selected voltage (near the voltage limit) of the electric generation device 24 is not exceeded. This process is called a continuous voltage control cycle 60 as illustrated in FIG. 2 and discussed below. Controlling the speed of the prime mover 26 such that the output of the electric generation device 24 does not exceed a voltage limit prevents the prime mover from cycling low speed to high speed, and back down to low speed due to an over-voltage condition at the electric generation device 24.

    [0028] Referring now to FIG. 2, a method of operating the transport refrigeration system is illustrated. As described herein, the method relies upon the controller 30 described above for monitoring and controlling the processes associated with operation of the transport refrigeration system 20. The controller 30 is in operative communication with the prime mover 26, the electric generation device 24, and the refrigeration unit 22. The method includes operating the prime mover 26 and the electric generation device 24 with the controller 30. The controller 30 also monitors operational parameters of the refrigeration unit 22 including at least one of a voltage of the electric generation device 24 and a speed of the prime mover 26. The controller 30 compares a voltage of the electric generation device 24 to a selected voltage and a speed of the prime mover 26 to a selected speed.

    [0029] In order to initiate cooling of a refrigerated cargo space, the method includes the controller 30 operating the prime mover 26 at a selected high speed at 72 to rapidly cool the refrigerated cargo space. The controller 30 continues operating the prime mover 26 at the selected high speed at 78 when the voltage of the electric generation device 24 does not exceed a voltage limit for a first selected time period at 74. In an exemplary embodiment, the voltage limit of the electric generation device 24 is equal to 600 volts. In an exemplary, the first selected time period is equal to 60 seconds.

    [0030] If the voltage of the electric generation device 24 exceeds the voltage limit for the first selected time period at 74, the controller 30 takes a corrective action at 76. At 76, the controller 30 operates the prime mover 26 at a selected low speed and the controller 30 initiates, at 80, a continuous voltage control cycle 60. The continuous voltage control cycle 60 includes the controller 30 operating the prime mover 26 at an increasing rate of speed until the voltage of the electric generation device 24 equals a selected voltage at 82. In a further embodiment, the selected voltage may be equal to 590 volts, which is lower than the voltage limit, e.g., 600 volts. The continuous voltage cycle 60 further includes the controller 30 exiting the continuous voltage control cycle 60 at 90 when the speed of the prime mover 26 equals a selected high speed and the voltage of the electric generation device 24 equals the selected voltage at 84. Block 90 indicates that the prime mover has reached the selected high speed and not exceeded the voltage limit. If, at 84, the speed of the prime mover 26 is not equal to the selected high speed, flow proceeds to 86 where the controller 30, after a second selected time period, determines if the voltage of the electric generation device 24 is lower than the selected voltage. If the voltage of the electric generation device 24 is not lower than the selected voltage, flow proceeds to 88 where the controller continues to operate the prime mover 26 at the current speed.

    [0031] If, after the second selected time period, the voltage of the electric generation device 24 is lower than the selected voltage at 86, flow proceeds to 92 where the controller 30 reinitiates the continuous voltage control cycle 60. Flow proceeds to 82 where the speed of the prime mover is again increased until the voltage output of the electric generation device 24 is at the selected voltage. The process continues until either the voltage output of the electric generation device 24 is at the selected voltage (at 88) or the prime mover 26 has reached the selected high speed (at 90).

    [0032] While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments.

    [0033] Accordingly, the invention is only limited by the scope of the appended claims.


    Claims

    1. A method of operating a transport refrigeration system (20) comprising:

    controlling, a first plurality of components of a refrigeration unit (22), wherein controlling comprises operating a prime mover (26) and an electric generation device (24); and

    operating, the prime mover at a selected high speed;

    monitoring, a plurality of operating parameters of the refrigeration unit, wherein at least one of the operating parameters is at least one of a voltage of the electric generation device and a speed of the prime mover;

    comparing, the voltage of the electric generation device to a selected voltage;

    comparing, the speed of the prime mover to a selected speed; and

    characterized by:

    taking a corrective action when the voltage of the electric generation device exceeds a voltage limit for a first selected time period, wherein the corrective action comprises: operating the prime mover at a selected low speed and the controller initiating a continuous voltage control cycle mode, and

    wherein the continuous voltage control cycle comprises: operating the prime mover at an increasing rate of speed until the voltage of the electric generation device equals the selected voltage, and exiting the continuous voltage control cycle when the speed of the prime mover (26) equals the selected high speed and the voltage of the electric generation device (24) equals the selected voltage.


     
    2. The method of claim 1, further comprising:
    operating the prime mover (26) at the selected high speed when the voltage of the electric generation device (22) does not exceed a voltage limit for a first selected time period.
     
    3. The method of claim 1 or 2, wherein the continuous voltage control cycle further includes:
    taking a second corrective action when the speed of the prime mover (26) is not equal to the selected high speed and the voltage of the electric generation device (24) equals the selected voltage.
     
    4. The method of claim 3, wherein the second corrective action comprises:
    reinitiating the continuous voltage control cycle when after a second selected time period, the voltage of the electric generation device (24) is lower than the selected voltage.
     
    5. The method of claim 3 or 4, wherein the second corrective action comprises:
    exiting the continuous voltage control cycle and continuing to operate the prime mover (26) at the current speed when after a second selected time period, the voltage of the electric generation device (24) is not lower than the selected voltage.
     
    6. A transport refrigeration system comprising:

    a prime mover (26);

    an electric generation device (24) powered by the prime mover and providing an electric output;

    a refrigeration unit (22) electrically powered by the electric output of the electric generation device; and

    a controller (30) in operative communication with the prime mover, the electric generation device, and the refrigeration unit,

    wherein the controller is configured to compare a voltage of the electric generation device to a selected voltage and a speed of the prime mover to a selected speed, and

    wherein the controller is configured to operate the prime mover at a selected high speed,

    characterized in that:

    the controller is configured to take a corrective action when the voltage of the electric generation device exceeds a voltage limit for a first selected time period,

    wherein the corrective action comprises the controller operating the prime mover at a selected low speed and the controller initiating a continuous voltage control cycle mode,

    wherein the continuous voltage control cycle comprises the controller operating the prime mover at an increasing rate of speed until the voltage of the electric generation device equals a selected voltage, and

    wherein the controller (30) is configured to exit the continuous voltage control cycle when the speed of the prime mover (26) equals the selected high speed and the voltage of the electric generation device (24) equals the selected voltage.


     
    7. The transport refrigeration system of claim 6, wherein:
    the controller (30) is configured to continue to operate the prime mover (26) at the selected high speed when the voltage of the electric generation device (24) does not exceed a voltage limit for a first selected time period.
     
    8. The transport refrigeration system of claim 6 or 7, wherein the continuous voltage control cycle further comprises:
    the controller (30) being configured to take a second corrective action when the speed of the prime mover (26) is not equal to the selected high speed and the voltage of the electric generation device (24) equals the selected voltage.
     
    9. The transport refrigeration system of claim 8, wherein the second corrective action comprises:
    the controller (30) being configured to reinitiate the continuous voltage control cycle when, after a second selected time period, the voltage of the electric generation device (24) is lower than the selected voltage.
     
    10. The transport refrigeration system of claim 8 or 9, wherein the second corrective action comprises:
    the controller (30) being configured to exit the continuous voltage control cycle and continue to operate the prime mover (26) at the current speed when, after a second selected time period, the voltage of the electric generation device (24) is not lower than the selected voltage.
     


    Ansprüche

    1. Verfahren zum Betreiben eines Transportkühlsystems (20), das Folgendes umfasst:

    Steuern einer ersten Vielzahl von Komponenten einer Kühleinheit (22), wobei das Steuern das Betreiben einer Antriebsmaschine (26) und einer Stromerzeugungsvorrichtung (24) umfasst; und

    Betreiben der Antriebsmaschine mit einer ausgewählten hohen Drehzahl;

    Überwachen einer Vielzahl von Betriebsparametern der Kühleinheit, wobei mindestens einer der Betriebsparameter mindestens einer von einer Spannung der Stromerzeugungsvorrichtung und einer Drehzahl der Antriebsmaschine ist;

    Vergleichen der Spannung der Stromerzeugungsvorrichtung mit einer ausgewählten Spannung;

    Vergleichen der Drehzahl der Antriebsmaschine mit einer ausgewählten Drehzahl; und

    gekennzeichnet durch:

    Ergreifen einer Korrekturmaßnahme, wenn die Spannung der Stromerzeugungsvorrichtung ein Spannungslimit während einer ersten ausgewählten Zeitspanne überschreitet, wobei die Korrekturmaßnahme Folgendes umfasst: Betreiben der Antriebsmaschine mit einer ausgewählten niedrigen Drehzahl und wobei die Steuereinheit einen kontinuierlichen Spannungssteuerzyklusmodus einleitet, und

    wobei der kontinuierliche Spannungssteuerzyklus Folgendes umfasst: Betreiben der Antriebsmaschine mit einer steigenden Drehzahlrate, bis die Spannung der Stromerzeugungsvorrichtung gleich der ausgewählten Spannung ist, und Verlassen des kontinuierlichen Spannungssteuerzyklus, wenn die Drehzahl der Antriebsmaschine (26) gleich der ausgewählten hohen Drehzahl ist und die Spannung der Stromerzeugungsvorrichtung (24) gleich der ausgewählten Spannung ist.


     
    2. Verfahren nach Anspruch 1, das weiter Folgendes umfasst:
    Betreiben der Antriebsmaschine (26) mit der ausgewählten hohen Drehzahl, wenn die Spannung der Stromerzeugungsvorrichtung (24) ein Spannungslimit während einer ersten ausgewählten Zeitspanne nicht überschreitet.
     
    3. Verfahren nach Anspruch 1 oder 2, wobei der kontinuierliche Spannungssteuerzyklus weiter Folgendes beinhaltet:
    Ergreifen einer zweiten Korrekturmaßnahme, wenn die Drehzahl der Antriebsmaschine (26) nicht gleich der ausgewählten hohen Drehzahl ist und die Spannung der Stromerzeugungsvorrichtung (24) gleich der ausgewählten Spannung ist.
     
    4. Verfahren nach Anspruch 3, wobei die zweite Korrekturmaßnahme Folgendes umfasst:
    erneutes Einleiten des kontinuierlichen Spannungssteuerzyklus, wenn nach einer zweiten ausgewählten Zeitspanne die Spannung der Stromerzeugungsvorrichtung (24) niedriger als die ausgewählte Spannung ist.
     
    5. Verfahren nach Anspruch 3 oder 4, wobei die zweite Korrekturmaßnahme Folgendes umfasst:
    Verlassen des kontinuierlichen Spannungssteuerzyklus und Fortsetzen des Betreibens der Antriebsmaschine (26) mit der aktuellen Drehzahl, wenn nach einer zweiten ausgewählten Zeitspanne die Spannung der Stromerzeugungsvorrichtung (24) nicht niedriger als die ausgewählte Spannung ist.
     
    6. Transportkühlsystem, das Folgendes umfasst:

    eine Antriebsmaschine (26);

    eine Stromerzeugungsvorrichtung (24), die von der Antriebsmaschine bestromt wird und eine elektrische Ausgabe bereitstellt;

    eine Kühleinheit (22), die von der elektrischen Ausgabe der Stromerzeugungsvorrichtung bestromt wird; und

    eine Steuereinheit (30) in betrieblicher Kommunikation mit der Antriebsmaschine, der Stromerzeugungsvorrichtung und der Kühleinheit,

    wobei die Steuereinheit dazu konfiguriert ist, eine Spannung der Stromerzeugungsvorrichtung mit einer ausgewählten Spannung und eine Drehzahl der Antriebsmaschine mit einer ausgewählten Drehzahl zu vergleichen, und

    wobei die Steuereinheit dazu konfiguriert ist, die Antriebsmaschine mit einer ausgewählten hohen Drehzahl zu betreiben,

    dadurch gekennzeichnet, dass:

    die Steuereinheit dazu konfiguriert ist, eine Korrekturmaßnahme zu ergreifen, wenn die Spannung der Stromerzeugungsvorrichtung ein Spannungslimit während einer ersten Zeitspanne überschreitet,

    wobei die Korrekturmaßnahme umfasst, dass die Steuereinheit die Antriebsmaschine mit einer ausgewählten niedrigen Drehzahl betreibt und die Steuereinheit einen kontinuierlichen Spannungssteuerzyklusmodus einleitet,

    wobei der kontinuierliche Spannungssteuerzyklus umfasst, dass die Steuereinheit die Antriebsmaschine mit einer steigenden Drehzahlrate betreibt, bis die Spannung der Stromerzeugungsvorrichtung gleich einer ausgewählten Spannung ist, und

    wobei die Steuereinheit (30) dazu konfiguriert ist, den kontinuierlichen Spannungssteuerzyklus zu verlassen, wenn die Drehzahl der Antriebsmaschine (26) gleich der ausgewählten hohen Drehzahl ist und die Spannung der Stromerzeugungsvorrichtung (24) gleich der ausgewählten Spannung ist.


     
    7. Transportkühlsystem nach Anspruch 6, wobei:
    die Steuereinheit (30) dazu konfiguriert ist, den Betrieb der Antriebsmaschine (26) mit der ausgewählten hohen Drehzahl fortzusetzen, wenn die Spannung der Stromerzeugungsvorrichtung (24) ein Spannungslimit während einer ersten ausgewählten Zeitspanne nicht überschreitet.
     
    8. Transportkühlsystem nach Anspruch 6 oder 7, wobei der kontinuierliche Spannungssteuerzyklus weiter Folgendes umfasst:
    dass die Steuereinheit (30) dazu konfiguriert ist, eine zweite Korrekturmaßnahme zu ergreifen, wenn die Drehzahl der Antriebsmaschine (26) nicht gleich der ausgewählten hohen Drehzahl ist und die Spannung der Stromerzeugungsvorrichtung (24) gleich der ausgewählten Spannung ist.
     
    9. Transportkühlsystem nach Anspruch 8, wobei die zweite Korrekturmaßnahme Folgendes umfasst:
    dass die Steuereinheit (30) dazu konfiguriert ist, den kontinuierlichen Spannungssteuerzyklus erneut einzuleiten, wenn nach einer zweiten ausgewählten Zeitspanne die Spannung der Stromerzeugungsvorrichtung (24) niedriger als die ausgewählte Spannung ist.
     
    10. Transportkühlsystem nach Anspruch 8 oder 9, wobei die zweite Korrekturmaßnahme Folgendes umfasst:
    dass die Steuereinheit (30) dazu konfiguriert ist, den kontinuierlichen Spannungssteuerzyklus zu verlassen und die Antriebsmaschine (26) mit der aktuellen Drehzahl zu betreiben, wenn nach einer zweiten ausgewählten Zeitspanne die Spannung der Stromerzeugungsvorrichtung (24) nicht niedriger als die ausgewählte Spannung ist.
     


    Revendications

    1. Procédé de fonctionnement d'un système de réfrigération de transport (20) comprenant :

    la commande d'une première pluralité de composants d'une unité de réfrigération (22), dans lequel la commande comprend le fonctionnement d'une machine motrice (26) et d'un dispositif générateur électrique (24) ; et

    le fonctionnement de la machine motrice à une grande vitesse sélectionnée ;

    la surveillance d'une pluralité de paramètres de fonctionnement de l'unité de réfrigération, dans lequel au moins un des paramètres de fonctionnement est au moins l'une d'une tension du dispositif générateur électrique et une vitesse de la machine motrice ;

    la comparaison de la tension du dispositif générateur électrique avec une tension sélectionnée ;

    la comparaison de la vitesse de la machine motrice avec une vitesse sélectionnée ; et

    caractérisé par :

    le déclenchement d'une action corrective lorsque la tension du dispositif générateur électrique dépasse une limite de tension pendant une première période sélectionnée, dans lequel l'action corrective comprend : le fonctionnement de la machine motrice à une petite vitesse sélectionnée et le lancement par le dispositif de commande d'un mode de cycle de régulation de tension continue, et

    dans lequel le cycle de régulation de tension continue comprend : le fonctionnement de la machine motrice à un régime de vitesse croissant jusqu'à ce que la tension du dispositif générateur électrique soit égale à la tension sélectionnée, et la sortie du cycle de régulation de tension continue lorsque la vitesse de la machine motrice (26) est égale à la grande vitesse sélectionnée et que la tension du dispositif générateur électrique (24) est égale à la tension sélectionnée.


     
    2. Procédé selon la revendication 1, comprenant en outre :
    le fonctionnement de la machine motrice (26) à la grande vitesse sélectionnée lorsque la tension du dispositif générateur électrique (24) ne dépasse pas une limite de tension pendant une première période sélectionnée.
     
    3. Procédé selon la revendication 1 ou 2, dans lequel le cycle de régulation de tension continue inclut en outre :
    le déclenchement d'une seconde action corrective lorsque la vitesse de la machine motrice (26) n'est pas égale à la grande vitesse sélectionnée et que la tension du dispositif générateur électrique (24) est égale à la tension sélectionnée.
     
    4. Procédé selon la revendication 3, dans lequel la seconde action corrective comprend :
    un nouveau lancement du cycle de régulation de tension continue lorsque, après une seconde période sélectionnée, la tension du dispositif générateur électrique (24) est inférieure à la tension sélectionnée.
     
    5. Procédé selon la revendication 3 ou 4, dans lequel la seconde action corrective comprend :
    la sortie du cycle de régulation de tension continue et la poursuite du fonctionnement de la machine motrice (26) à la vitesse courante lorsque, après une seconde période sélectionnée, la tension du dispositif générateur électrique (24) n'est pas inférieure à la tension sélectionnée.
     
    6. Système de réfrigération de transport comprenant :

    une machine motrice (26) ;

    un dispositif générateur électrique (24) entraîné par la machine motrice et délivrant une puissance de sortie électrique ;

    une unité de réfrigération (22) entraînée électriquement par la puissance de sortie électrique du dispositif générateur électrique ; et

    un dispositif de commande (30) en communication fonctionnelle avec la machine motrice, le dispositif générateur électrique et l'unité de réfrigération,

    dans lequel le dispositif de commande est configuré pour comparer une tension du dispositif générateur électrique avec une tension sélectionnée et une vitesse de la machine motrice avec une vitesse sélectionnée, et

    dans lequel le dispositif de commande est configuré pour faire fonctionner la machine motrice à une grande vitesse sélectionnée,

    caractérisé en ce que :

    le dispositif de commande est configuré pour déclencher une action corrective lorsque la tension du dispositif générateur électrique dépasse une limite de tension pendant une première période sélectionnée,

    dans lequel l'action corrective comprend le fonctionnement par le dispositif de commande de la machine motrice à une petite vitesse sélectionnée et le lancement par le dispositif de commande d'un mode de cycle de régulation de tension continue,

    dans lequel le cycle de régulation de tension continue comprend : le fonctionnement par le dispositif de commande de la machine motrice à un régime de vitesse croissant jusqu'à ce que la tension du dispositif générateur électrique soit égale à une tension sélectionnée, et

    dans lequel le dispositif de commande (30) est configuré pour sortir du cycle de régulation de tension continue lorsque la vitesse de la machine motrice (26) est égale à la grande vitesse sélectionnée et que la tension du dispositif générateur électrique (24) est égale à la tension sélectionnée.


     
    7. Système de réfrigération de transport selon la revendication 6, dans lequel :
    le dispositif de commande (30) est configuré pour continuer à faire fonctionner la machine motrice (26) à la grande vitesse sélectionnée lorsque la tension du dispositif générateur électrique (24) ne dépasse pas une limite de tension pendant une première période sélectionnée.
     
    8. Système de réfrigération de transport selon la revendication 6 ou 7, dans lequel le cycle de régulation de tension continue comprend en outre :
    la configuration du dispositif de commande (30) pour déclencher une seconde action corrective lorsque la vitesse de la machine motrice (26) n'est pas égale à la grande vitesse sélectionnée et que la tension du dispositif générateur électrique (24) est égale à la tension sélectionnée.
     
    9. Système de réfrigération de transport selon la revendication 8, dans lequel la seconde action corrective comprend :
    la configuration du dispositif de commande (30) pour lancer de nouveau le cycle de régulation de tension continue lorsque, après une seconde période sélectionnée, la tension du dispositif générateur électrique (24) est inférieure à la tension sélectionnée.
     
    10. Système de réfrigération de transport selon la revendication 8 ou 9, dans lequel la seconde action corrective comprend :
    la configuration du dispositif de commande (30) pour sortir du cycle de régulation de tension continue et continuer de faire fonctionner la machine motrice (26) à la vitesse courante lorsque, après une seconde période sélectionnée, la tension du dispositif générateur électrique (24) n'est pas inférieure à la tension sélectionnée.
     




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    Cited references

    REFERENCES CITED IN THE DESCRIPTION



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    Patent documents cited in the description