EP2956671A1 - Method for controlling a compressor of a refrigeration system, said compressor having a motor, and compressor of a refrigeration system - Google Patents

Method for controlling a compressor of a refrigeration system, said compressor having a motor, and compressor of a refrigeration system

Info

Publication number
EP2956671A1
EP2956671A1 EP14703391.4A EP14703391A EP2956671A1 EP 2956671 A1 EP2956671 A1 EP 2956671A1 EP 14703391 A EP14703391 A EP 14703391A EP 2956671 A1 EP2956671 A1 EP 2956671A1
Authority
EP
European Patent Office
Prior art keywords
valve
compressor
percentage
time
time interval
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP14703391.4A
Other languages
German (de)
French (fr)
Other versions
EP2956671B1 (en
Inventor
Kurt Jansen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kriwan Industrie Elektronik GmbH
Original Assignee
Kriwan Industrie Elektronik GmbH
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Filing date
Publication date
Application filed by Kriwan Industrie Elektronik GmbH filed Critical Kriwan Industrie Elektronik GmbH
Publication of EP2956671A1 publication Critical patent/EP2956671A1/en
Application granted granted Critical
Publication of EP2956671B1 publication Critical patent/EP2956671B1/en
Not-in-force legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/02—Stopping, starting, unloading or idling control
    • F04B49/03—Stopping, starting, unloading or idling control by means of valves
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/06—Control using electricity
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/06—Control using electricity
    • F04B49/065—Control using electricity and making use of computers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/22—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00 by means of valves
    • F04B49/225—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00 by means of valves with throttling valves or valves varying the pump inlet opening or the outlet opening
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B13/00—Compression machines, plants or systems, with reversible cycle

Definitions

  • the invention relates to a method for controlling a compressor having a motor of a refrigeration system, wherein a controller controls the flow of refrigerant through the compressor via at least one valve. Furthermore, the invention relates to a compressor of a refrigeration system.
  • a controller for determining the current refrigeration demand of a refrigeration point is provided next to the compressor. If the controller detects an increased need for cooling, the compressor is controlled by the controller in the sense of an increase in output.
  • a method for controlling the performance of a refrigeration compressor comprising a pneumatic or hydraulic servo device for the intermittent interruption of the supply of refrigerant to a suction chamber. Furthermore, the compressor has a regulator, by which a pulse-width-modulated switching signal for the pneumatic or hydraulic servo device can be generated for controlling the intermittent interruption of the refrigerant supply.
  • the duty-pause ratio for controlling the pneumatic or hydraulic servo device can be adapted to the needs of the cooling point.
  • the valve for influencing the refrigerant flow is controlled by a pulse width modulated switching signal, wherein the valve is fully opened in one phase of a time interval and completely closed in the other phase.
  • the ratio of the two phases reflects the currently required cooling demand of the cooling point.
  • the power of the compressor can be adjusted from 0 to 100%.
  • a cycle time of 10 s on the one hand, it is possible to react very quickly to changes in the refrigeration demand of the refrigeration unit, and, on the other hand, the maintenance frequency of the valve is reduced to an acceptable level limited. Although a shorter cycle time would shorten the reaction time to changed conditions of the cooling point, but also the life of the valves used would shorten accordingly.
  • the invention is based on the object to improve the method for controlling a compressor having a motor of a refrigeration system or the compressor of a refrigeration system to the effect that still gives a quick response to changes in refrigeration demand of the refrigeration and the number of switching operations of the valve is significantly reduced from the opening to the closed position and vice versa.
  • the refrigerant flow is controlled by the compressor via at least one valve, wherein the valve is driven in time with successive and equal time intervals either in terms of opening or in the sense of closure, so the valve is either fully closed or fully open during a time interval, where a. a percentage of the compressor power corresponding to the current refrigeration demand of a refrigeration point is determined, b. the percentage opening time of the valve is determined over a number of time intervals comprising the current time interval and subsequent preceding time intervals, c. the valve is opened for the following time interval when the ratio of the compressor's refrigeration requirement percentage power is greater than the historical percentage opening time of the valve; and d. the valve is closed for the following time interval when the ratio of the compressor's percentage duty to refrigeration demand is less than the percent opening time of the valve determined for the past.
  • the compressor of a refrigeration system consists essentially of a motor for compressing a refrigerant flow, at least one valve for influencing the amount of refrigerant flow through the compressor of a control device for controlling the valve, wherein the valve in time with successive and equal time intervals either in the sense an opening or in the sense of a closure is controlled, so that the valve during a time interval is either completely closed or fully open, at least one sensor unit for determining the instantaneous cooling demand of a cooling point corresponding percentage power of the compressor, an evaluation unit for determining the percentage opening time of the Valve over a number of time intervals, which include the current time interval and adjoining previous time intervals, the control device with the evaluation in dacaun g, and is configured to open the valve for the following time interval when the ratio of the compressor's demand corresponding to the refrigeration demand is greater than the historical percentage opening time of the valve, and the valve for the subsequent time interval is closed when the ratio of the compressor corresponding to the refrigeration demand, percentage of power of the compressor is smaller than the determined
  • valve While in EP 0 982 497 B1 the valve is once opened and closed once in each time interval / cycle, the valve remains in a state over the entire time interval according to the regulation according to the invention.
  • the valve is thus not driven by a pulse width modulated signal, but it is the percent opening time over a number of time intervals, which includes the current time interval and adjoining previous time intervals determined and compared with the just required percentage of power of the compressor. This may also have the result that the valve remains closed or opened in succession over several time intervals.
  • the length of the time interval is chosen to be similar to that in EP 0 982 497 B1 and is preferably in the range from 2 to 20 s. If the measurement of the refrigeration demand of the refrigeration point takes place in comparably short time intervals, it is thus possible to react to a possibly changed refrigeration requirement at the next time interval. However, the switching frequency of the valve required for the realization of the method is significantly reduced. After valves for a certain S ehalt frequency are designed, the valves can be used according to the method according to the invention correspondingly longer.
  • the proportional to the current cooling demand of a cooling point, proportional power of the compressor is determined in time with the time interval. Furthermore, the ratio of the proportional refrigerant compressor power corresponding to the refrigeration demand can be compared with the determined for the past percentage opening time for each cycle of the valve. Furthermore, it has proven to be expedient if at least two and at most 7, preferably 3 to 5, past time intervals are used for determining the percentage opening time of the valve. A smaller number leads to too high a frequency of the switching intervals and a consideration of more than 7 time intervals results in a correspondingly slower adaptation to changed conditions of the cooling point. Furthermore, it can be provided that the duration of the time interval is adjustable. Thus, while keeping temperature within a more limited range, a refrigeration point requires a faster response and thus shorter time intervals than a refrigeration point, where less critical demands are made.
  • Fig. 1 is a schematic diagram of a refrigeration system
  • Fig. 2 is an illustration of the valve position as a function of the refrigeration demand of
  • the refrigeration plant shown schematically in Fig. 1 consists essentially of a compressor 1, a condenser 2, a collector 3, an expansion valve 4 and an evaporator 5.
  • the compressor 1 which is for example designed as a reciprocating compressor, vapor refrigerant is sucked and compressed.
  • the refrigerant is condensed and passes through the collector 3 to the expansion valve 4, where it is relaxed.
  • the refrigerant pressure decreases, causing the refrigerant to cool and partially evaporate.
  • the evaporator 5 which is arranged in the region of a cooling point 6, the refrigerant absorbs the heat of the cooling point by evaporation.
  • the refrigerant flow is controlled by means of at least one valve 7 arranged on or in the compressor as a function of the refrigeration requirement of the refrigerating point 6.
  • the valve 7 is in the illustrated embodiment on the suction side of the compressor 1, that is arranged between the evaporator 5 and compressor 1. In this case, an opening of the valve 7 leads to an increase of the refrigerant flow and a closing to a reduction of the refrigerant flow.
  • valve 7 could also be arranged in a bypass line 8 to the compressor 1 (variant shown in dashed lines).
  • the refrigerant flow through the compressor 1 would be increased by closing the valve and reduced by opening.
  • a sensor unit 9 is provided, via which a percentage of the compressor 1 corresponding to the instantaneous cooling requirement of the cooling point 6 is determined. Furthermore, an evaluation unit 10 which is in communication with the sensor unit 9 is provided, which determines the percentage opening time F of the valve 7 over a number of time intervals I, the time intervals comprising the current time interval I n and preceding time intervals following thereon.
  • a controller 11 connected to the evaluation unit is provided, which is designed in such a way that the valve 7 is opened for the following time interval I n + 1 when the ratio of the refrigeration requirement corresponding to the percentage power S of the compressor 1 is greater than that is the percentage opening time F of the valve determined for the past, and the valve is closed for the following time interval I n + 1 when the ratio of the refrigeration demand percentage power S of the compressor is less than the historical opening percentage F of the valve is.
  • the length of a time interval I in this embodiment is 10 s and for the determination of the percentage opening time F of the valve 7 five time intervals, ie the current time interval I n and the preceding four time intervals (I n-1 , I n-2 , I n _3, I n- 4) formed.
  • the percentage opening time F of the valve 7 is indicated by a solid line and the percent cooling capacity S of the compressor corresponding to the current refrigeration demand is shown in dashed line.
  • the proportional power S of the compressor corresponding to the refrigeration requirement in the first five time intervals L to I 5 0%.
  • the power S 89% and then drops first to 30% and later to 10%, before it rises again.
  • the evaluation unit 10 determines the percentage opening time F of the valve 7 over five time intervals with the formula given below:
  • the following table shows the refrigeration demand as a percentage power S of the compressor 1, the percentage opening time F of the valve 7 and the valve state V during the first 27 time intervals of the example shown in FIG.
  • the valve state of five time intervals is considered, which includes the current time interval and the four past time intervals. After each time interval, the time window shifts down by one interval. Two such time windows are shown by way of example in the following table.
  • the valve After 89% is significantly larger than F, the valve remains open in the 7th time interval.
  • the valve is closed only for the 11th time interval since the valve has been open for five time intervals (namely from the 6th to 10th time intervals) and thus the percentage opening time F of the valve over the five time intervals is 100% and thus S less than F is.
  • the refrigeration demand S is only 30%.
  • the valve is therefore closed again from the 21st time interval. Accordingly, the value F for the percentage opening time of the valve steadily decreases over the following time intervals.
  • the time intervals 20 to 24 are evaluated (see second time window in the table), wherein in these time intervals the valve was open only in a time interval, namely the 20th time interval. This results in a percentage opening time of only 20%> which is thus below the refrigeration requirement S of 30%>. Accordingly, the valve is opened again in the 25th time interval.
  • the new cooling demand is satisfied correspondingly slower, since the valve is driven with exactly the same opening and closing times, the ratio of which corresponds to the new refrigeration demand.
  • the great advantage of the above method lies in the significantly reduced switching frequency of the valve.
  • the S ehalt frequency of the valve can be reduced by up to 75% and more. This in turn ensures a correspondingly longer life of the valve.

Abstract

In the method according to the invention for controlling a compressor of a refrigeration system, said compressor having a motor, the refrigerant flow through the compressor is controlled by means of at least one valve, wherein the valve is either opened or closed in a cycle of consecutive and equally long intervals, so that the valve is either completely closed or completely open during an interval, wherein a. a percentage output of the compressor corresponding to the momentary cooling demand of a cooling point is determined, b. the percentage opening time of the valve is determined over a number of intervals which comprise the current interval and preceding intervals running up to the current interval, c. the valve is opened for the following interval if the ratio of the percentage output of the compressor corresponding to the cooling demand is greater than the percentage opening time of the valve previously determined, and d. the valve is closed for the following interval if the ratio of the percentage output of the compressor corresponding to the cooling demand is less than the percentage opening time of the valve previously determined.

Description

Verfahren zur Regelung eines einen Motor aufweisenden Verdichters einer Kälteanlage und ein Verdichter einer Kälteanlage  Method for controlling a compressor having a motor of a refrigeration system and a compressor of a refrigeration system
Die Erfindung betrifft ein Verfahren zur Regelung eines einen Motor aufweisenden Verdichters einer Kälteanlage, wobei eine Steuerung den Kältemittelstrom durch den Verdichter über mindestens ein Ventil steuert. Weiterhin bezieht sich die Erfindung auf einen Verdichter einer Kälteanlage. The invention relates to a method for controlling a compressor having a motor of a refrigeration system, wherein a controller controls the flow of refrigerant through the compressor via at least one valve. Furthermore, the invention relates to a compressor of a refrigeration system.
Bei herkömmlichen Kälteanlagen ist neben dem Verdichter ein Regler zur Ermittlung des aktuellen Kältebedarfs einer Kühlstelle vorgesehen. Stellt der Regler einen erhöhten Kältebedarf fest, wird der Verdichter vom Regler im Sinne einer Leistungserhöhung angesteuert. In conventional refrigeration systems, a controller for determining the current refrigeration demand of a refrigeration point is provided next to the compressor. If the controller detects an increased need for cooling, the compressor is controlled by the controller in the sense of an increase in output.
Aus der DE 10 2004 048 940 AI ist ein Verfahren zur Regelung der Leistung eines Kälteanlagen- Verdichters bekannt, wobei der Verdichter eine pneumatische oder hydraulische Servoeinrichtung zur intermittierenden Unterbrechung der Zufuhr von Kältemittel zu einem Saugraum aufweist. Ferner weist der Verdichter einen Regler auf, durch den zur Regelung der intermittierenden Unterbrechung der Kältemittelzufuhr ein pulsweitenmoduliertes Schaltsignal für die pneumatische oder hydraulische Servoreinrichtung erzeugbar ist. Das Tast-Pausen- Verhältnis zur Ansteuerung der pneumatischen oder hydraulischen Servoeinrichtung kann dabei an dem Bedarf der Kühlstelle angepasst werden. From DE 10 2004 048 940 AI a method for controlling the performance of a refrigeration compressor is known, wherein the compressor comprises a pneumatic or hydraulic servo device for the intermittent interruption of the supply of refrigerant to a suction chamber. Furthermore, the compressor has a regulator, by which a pulse-width-modulated switching signal for the pneumatic or hydraulic servo device can be generated for controlling the intermittent interruption of the refrigerant supply. The duty-pause ratio for controlling the pneumatic or hydraulic servo device can be adapted to the needs of the cooling point.
Auch in der EP 982 497 Bl wird das Ventil zur Beeinflussung des Kältemittelstroms durch ein pulsweitenmoduliertes Schaltsignal angesteuert, wobei das Ventil in einer Phase eines Zeitintervalls vollständig geöffnet und in der anderen Phase vollständig geschlossen ist. Das Verhältnis der beiden Phasen spiegelt dabei den momentan erforderlichen Kältebedarf der Kühlstelle wider. Durch die Einstellung des Verhältnisses von Öffnungsphase und Schließphase lässt sich die Leistung des Verdichters von 0 bis 100% einstellen. Mit einer Zykluszeit von 10 s kann einerseits sehr schnell auf Änderungen des Kältebedarfs der Kühlstelle reagiert werden und andererseits wird die S ehalt häufigkeit des Ventils auf ein erträgliches Maß beschränkt. Eine kürzere Zykluszeit würde zwar die Reaktionszeit auf geänderte Bedingungen der Kühlstelle verkürzen, jedoch würde sich auch die Lebendauer der eingesetzten Ventile entsprechend verkürzen. Also in EP 982 497 B1, the valve for influencing the refrigerant flow is controlled by a pulse width modulated switching signal, wherein the valve is fully opened in one phase of a time interval and completely closed in the other phase. The ratio of the two phases reflects the currently required cooling demand of the cooling point. By adjusting the ratio of opening phase and closing phase, the power of the compressor can be adjusted from 0 to 100%. With a cycle time of 10 s, on the one hand, it is possible to react very quickly to changes in the refrigeration demand of the refrigeration unit, and, on the other hand, the maintenance frequency of the valve is reduced to an acceptable level limited. Although a shorter cycle time would shorten the reaction time to changed conditions of the cooling point, but also the life of the valves used would shorten accordingly.
Der Erfindung liegt nun die Aufgabe zugrunde das Verfahren zur Regelung eines einen Motor aufweisenden Verdichters einer Kälteanlage bzw. den Verdichter einer Kälteanlage dahingehend zu verbessern, dass nach wie vor eine schnelle Reaktion auf Änderungen des Kältebedarfs der Kältestelle gegeben ist und die Anzahl der Schaltvorgänge des Ventils von der Öffnungs- zur Schließstellung und umgekehrt deutlich reduziert wird. The invention is based on the object to improve the method for controlling a compressor having a motor of a refrigeration system or the compressor of a refrigeration system to the effect that still gives a quick response to changes in refrigeration demand of the refrigeration and the number of switching operations of the valve is significantly reduced from the opening to the closed position and vice versa.
Erfindungsgemäß wird diese Aufgabe durch die Merkmale der Ansprüche 1 und 8 gelöst. According to the invention, this object is solved by the features of claims 1 and 8.
Beim erfindungsgemäßen Verfahren zur Regelung eines einen Motor aufweisenden Verdichters einer Kälteanlage wird der Kältemittelstrom durch den Verdichter über mindestens ein Ventil gesteuert, wobei das Ventil im Takt von aufeinander folgenden und gleich langen Zeitintervallen entweder im Sinne einer Öffnung oder im Sinne einer Schließung angesteuert wird, sodass das Ventil während eines Zeitintervalls entweder vollständig geschlossen oder vollständig geöffnet ist, wobei a. eine dem momentanen Kältebedarf einer Kühlstelle entsprechende, prozentuale Leistung des Verdichters ermittelt wird, b. die prozentuale Öffnungszeit des Ventils über eine Anzahl von Zeitintervallen, die das aktuelle Zeitintervall und sich daran anschließende vorhergehende Zeitintervalle umfassen, ermittelt wird, c. das Ventil für das folgende Zeitintervall geöffnet wird, wenn das Verhältnis der dem Kältebedarf entsprechenden, prozentualen Leistung des Verdichters größer als die für die Vergangenheit ermittelte, prozentuale Öffnungszeit des Ventils ist und d. das Ventil für das folgende Zeitintervall geschlossen wird, wenn das Verhältnis der dem Kältebedarf entsprechenden, prozentualen Leistung des Verdichters kleiner als die für die Vergangenheit ermittelte, prozentuale Öffnungszeit des Ventils ist. In the method according to the invention for controlling a compressor having a compressor of a refrigeration system, the refrigerant flow is controlled by the compressor via at least one valve, wherein the valve is driven in time with successive and equal time intervals either in terms of opening or in the sense of closure, so the valve is either fully closed or fully open during a time interval, where a. a percentage of the compressor power corresponding to the current refrigeration demand of a refrigeration point is determined, b. the percentage opening time of the valve is determined over a number of time intervals comprising the current time interval and subsequent preceding time intervals, c. the valve is opened for the following time interval when the ratio of the compressor's refrigeration requirement percentage power is greater than the historical percentage opening time of the valve; and d. the valve is closed for the following time interval when the ratio of the compressor's percentage duty to refrigeration demand is less than the percent opening time of the valve determined for the past.
Der erfindungsgemäße Verdichter einer Kälteanlage besteht im Wesentlichen aus einem Motor zur Verdichtung eines Kältemittelstroms, mindestens einem Ventil zur Beeinflussung der Menge des Kältemittelstroms durch den Verdichter einer Steuereinrichtung zur Steuerung des Ventils, wobei das Ventil im Takt von aufeinander folgenden und gleich langen Zeitintervallen entweder im Sinne einer Öffnung oder im Sinne einer Schließung ansteuerbar ist, sodass das Ventil während eines Zeitintervalls entweder vollständig geschlossen oder vollständig geöffnet ist, wenigstens einer Sensoreinheit zur Ermittlung einer dem momentanen Kältebedarf einer Kühlstelle entsprechenden, prozentualen Leistung des Verdichters, einer Auswerteeinheit zur Ermittlung der prozentualen Öffnungszeit des Ventils über eine Anzahl von Zeitintervallen, die das aktuelle Zeitintervall und sich daran anschließende vorhergehende Zeitintervalle umfassen, wobei die Steuereinrichtung mit der Auswerteeinheit in Verbindung steht und derart ausgebildet ist, dass das Ventil für das folgende Zeitintervall geöffnet wird, wenn das Verhältnis der dem Kältebedarf entsprechenden, prozentualen Leistung des Verdichters größer als die für die Vergangenheit ermittelte, prozentuale Öffnungszeit des Ventils ist, und das Ventil für das folgende Zeitintervall geschlossen wird, wenn das Verhältnis der dem Kältebedarf entsprechenden, prozentualen Leistung des Verdichters kleiner als die für die Vergangenheit ermittelte, prozentuale Öffnungszeit des Ventils ist. Während bei der EP 0 982 497 Bl in jedem Zeitintervall/Zyklus das Ventil einmal geöffnet und einmal geschlossen wird, bleibt das Ventil gemäß der erfindungsgemäßen Regelung über das gesamte Zeitintervall in einem Zustand. Das Ventil wird somit nicht mit einem pulsweitenmodulierten Signal angesteuert, sondern es wird die prozentuale Öffnungszeit über eine Anzahl von Zeitintervallen, die das aktuelle Zeitintervall und sich daran anschließende vorhergehende Zeitintervalle umfasst, ermittelt und mit der gerade erforderlichen prozentualen Leistung des Verdichters verglichen. Dies kann auch zufolge haben, dass das Ventil über mehrere Zeitintervalle hintereinander geschlossen oder geöffnet bleibt. The compressor of a refrigeration system according to the invention consists essentially of a motor for compressing a refrigerant flow, at least one valve for influencing the amount of refrigerant flow through the compressor of a control device for controlling the valve, wherein the valve in time with successive and equal time intervals either in the sense an opening or in the sense of a closure is controlled, so that the valve during a time interval is either completely closed or fully open, at least one sensor unit for determining the instantaneous cooling demand of a cooling point corresponding percentage power of the compressor, an evaluation unit for determining the percentage opening time of the Valve over a number of time intervals, which include the current time interval and adjoining previous time intervals, the control device with the evaluation in Verbindungun g, and is configured to open the valve for the following time interval when the ratio of the compressor's demand corresponding to the refrigeration demand is greater than the historical percentage opening time of the valve, and the valve for the subsequent time interval is closed when the ratio of the compressor corresponding to the refrigeration demand, percentage of power of the compressor is smaller than the determined for the past, percentage opening time of the valve. While in EP 0 982 497 B1 the valve is once opened and closed once in each time interval / cycle, the valve remains in a state over the entire time interval according to the regulation according to the invention. The valve is thus not driven by a pulse width modulated signal, but it is the percent opening time over a number of time intervals, which includes the current time interval and adjoining previous time intervals determined and compared with the just required percentage of power of the compressor. This may also have the result that the valve remains closed or opened in succession over several time intervals.
Die Länge des Zeitintervalls wird ähnlich kurz wie in der EP 0 982 497 Bl gewählt und liegt vorzugsweise im Bereich von 2 bis 20 s. Erfolgt die Messung des Kältebedarfs der Kühlstelle in vergleichbar kurzen Zeitintervallen, kann somit bereits beim nächsten Zeitintervall auf einen ggf. geänderten Kältebedarf reagiert werden. Die für die Realisierung des Verfahrens erforderliche Schalthäufigkeit des Ventils ist jedoch deutlich reduziert. Nachdem Ventile für eine bestimmte S ehalt häufigkeit ausgelegt sind, können die Ventile mit dem erfhdungsgemäßen Verfahren entsprechend länger eingesetzt werden. The length of the time interval is chosen to be similar to that in EP 0 982 497 B1 and is preferably in the range from 2 to 20 s. If the measurement of the refrigeration demand of the refrigeration point takes place in comparably short time intervals, it is thus possible to react to a possibly changed refrigeration requirement at the next time interval. However, the switching frequency of the valve required for the realization of the method is significantly reduced. After valves for a certain S ehalt frequency are designed, the valves can be used according to the method according to the invention correspondingly longer.
Weitere Ausgestaltungen der Erfindung sind Gegenstand der Unter anspräche. Further embodiments of the invention are the subject of the subclaims.
Gemäß einer bevorzugten Ausgestaltung der Erfindung wird die dem momentanen Kältebedarf einer Kühlstelle entsprechende, proportionale Leistung des Verdichters im Takt des Zeitintervalls ermittelt. Weiterhin kann das Verhältnis der dem Kältebedarf entsprechenden proportionalen Leistung des Verdichters mit der für die Vergangenheit ermittelten prozentualen Öffnungszeit für jeden Takt des Ventils verglichen werden. Des Weiteren hat sich als zweckmäßig herausgestellt, wenn wenigstens zwei und maximal 7, vorzugsweise 3 bis 5, vergangene Zeitintervalle für die Ermittelung der prozentualen Öffnungszeit des Ventils herangezogen werden. Eine geringere Anzahl führt zur einer zu großen Häufigkeit der Schaltintervalle und eine Berücksichtigung von mehr als 7 Zeitintervallen hat eine entsprechend langsamere Anpassung an geänderte Bedingungen der Kühlstelle zur Folge. Weiterhin kann vorgesehen werden, dass die Dauer des Zeitintervalls einstellbar ist. So erfordert eine Kühlstelle, während Temperatur in einem engeren Rahmen gehalten werden muss, eine schnellere Reaktion und damit kürzere Zeitintervalle als eine Kühlstelle, bei der weniger kritische Anforderungen gestellt werden. According to a preferred embodiment of the invention, the proportional to the current cooling demand of a cooling point, proportional power of the compressor is determined in time with the time interval. Furthermore, the ratio of the proportional refrigerant compressor power corresponding to the refrigeration demand can be compared with the determined for the past percentage opening time for each cycle of the valve. Furthermore, it has proven to be expedient if at least two and at most 7, preferably 3 to 5, past time intervals are used for determining the percentage opening time of the valve. A smaller number leads to too high a frequency of the switching intervals and a consideration of more than 7 time intervals results in a correspondingly slower adaptation to changed conditions of the cooling point. Furthermore, it can be provided that the duration of the time interval is adjustable. Thus, while keeping temperature within a more limited range, a refrigeration point requires a faster response and thus shorter time intervals than a refrigeration point, where less critical demands are made.
Die prozentuale Öffnungszeit des Ventils über eine Anzahl von Zeitintervallen kann beispielsweise mit der nachfolgend angegebenen Formel ermittelt werden: f = £___! L For example, the percentage opening time of the valve over a number of time intervals can be determined using the formula given below: f = £ ___! L
m + 1  m + 1
mit  With
F: prozentuale Öffnungszeit des Ventils,  F: percentage opening time of the valve,
In: aktuelles Zeitintervall, I n : current time interval,
m: Anzahl der zu berücksichtigenden, vergangenen Zeitintervalle und  m: number of past time intervals to be considered and
Vt: Status des Ventils bei einem bestimmten Zeitintervall t (100 = offen oder 0 = geschlossen) V t : status of the valve at a certain time interval t (100 = open or 0 = closed)
Weitere Ausgestaltungen der Erfindung werden im Folgenden anhand der Beschreibung eines Ausführungsbeispieles und der Zeichnung näher erläutert.  Further embodiments of the invention are explained in more detail below with reference to the description of an embodiment and the drawing.
In der Zeichnung zeigen In the drawing show
Fig. 1 eine Prinzipdarstellung einer Kälteanlage und Fig. 1 is a schematic diagram of a refrigeration system and
Fig. 2 eine Darstellung der Ventilstellung in Abhängigkeit des Kältebedarfs der Fig. 2 is an illustration of the valve position as a function of the refrigeration demand of
Kühlstelle.  Cool place.
Die in Fig. 1 schematisch dargestellte Kälteanlage besteht im Wesentlichen aus einem Verdichter 1 , einem Verflüssiger 2, einem Sammler 3, einem Expansionsventil 4 und einem Verdampfer 5. Im Verdichter 1 , der beispielsweise als Hubkolbenverdichter ausgebildet ist, wird dampfförmiges Kältemittel angesaugt und verdichtet. Im nachfolgenden Verflüssiger 2 wird das Kältemittel kondensiert und gelangt über den Sammler 3 zum Expansionsventil 4, wo es entspannt wird. Bei der Expansion nimmt der Kältemitteldruck ab, sodass das Kältemittel abkühlt und teilweise verdampft. Im Verdampfer 5, der im Bereich einer Kühlstelle 6 angeordnet ist, nimmt das Kältemittel durch Verdampfen die Wärme der Kühlstelle auf. Der Verdichter 1 saugt das verdampfte Kältemittel wieder an, sodass der Kältemittelkreislauf geschlossen ist. Der Kältemittelstrom wird mit Hilfe wenigstens eines am oder im Verdichter angeordneten Ventils 7 in Abhängigkeit des Kältebedarfs der Kühlstelle 6 gesteuert. Das Ventil 7 ist im dargestellten Ausführungsbeispiel auf der Saugseite des Verdichters 1, d. h. zwischen Verdampfer 5 und Verdichter 1 angeordnet. Dabei führt ein Öffnen des Ventils 7 zu einer Erhöhung des Kältemittelstroms und ein Schließen zu einer Verringerung des Kältemittelstroms . The refrigeration plant shown schematically in Fig. 1 consists essentially of a compressor 1, a condenser 2, a collector 3, an expansion valve 4 and an evaporator 5. In the compressor 1, which is for example designed as a reciprocating compressor, vapor refrigerant is sucked and compressed. In the following condenser 2, the refrigerant is condensed and passes through the collector 3 to the expansion valve 4, where it is relaxed. During expansion, the refrigerant pressure decreases, causing the refrigerant to cool and partially evaporate. In the evaporator 5, which is arranged in the region of a cooling point 6, the refrigerant absorbs the heat of the cooling point by evaporation. Of the Compressor 1 sucks in the vaporized refrigerant again so that the refrigerant circuit is closed. The refrigerant flow is controlled by means of at least one valve 7 arranged on or in the compressor as a function of the refrigeration requirement of the refrigerating point 6. The valve 7 is in the illustrated embodiment on the suction side of the compressor 1, that is arranged between the evaporator 5 and compressor 1. In this case, an opening of the valve 7 leads to an increase of the refrigerant flow and a closing to a reduction of the refrigerant flow.
Alternativ könnte das Ventil 7 auch in einer Bypassleitung 8 zum Verdichter 1 angeordnet werden (gestrichelt dargestellte Variante). Bei einem im Bypass 8 angeordneten Ventil würde der Kältemittelstrom durch den Verdichter 1 durch Schließen des Ventils erhöht und durch Öffnen verringert. Alternatively, the valve 7 could also be arranged in a bypass line 8 to the compressor 1 (variant shown in dashed lines). In a valve arranged in the bypass 8, the refrigerant flow through the compressor 1 would be increased by closing the valve and reduced by opening.
Im Bereich der Kühlstelle 6 ist eine Sensoreinheit 9 vorgesehen, über die eine dem momentanen Kältebedarf der Kühlstelle 6 entsprechende, prozentuale Leistung S des Verdichters 1 ermittelt wird. Weiterhin ist eine mit der Sensoreinheit 9 in Verbindung stehende Auswerteeinheit 10 vorgesehen, welche die prozentuale Öffnungszeit F des Ventils 7 über eine Anzahl von Zeitintervallen I ermittelt, wobei die Zeitintervalle das aktuelle Zeitintervall In und sich daran anschließende vorhergehende Zeitintervalle umfasst. Weiterhin ist eine mit der Auswerteeinheit in Verbindung stehende Steuereinrichtung 11 vorgesehen, die derart ausgebildet ist, dass das Ventil 7 für das folgende Zeitintervall In+1 geöffnet wird, wenn das Verhältnis der dem Kältebedarf entsprechenden, prozentualen Leistung S des Verdichters 1 größer als die für die Vergangenheit ermittelte prozentuale Öffnungszeit F des Ventils ist, und das Ventil für das folgende Zeitintervall In+1 geschlossen wird, wenn das Verhältnis der dem Kältebedarf entsprechenden, prozentuale Leistung S des Verdichters kleiner als die für die Vergangenheit ermittelte prozentuale Öffnungszeit F des Ventils ist. In the area of the cooling point 6, a sensor unit 9 is provided, via which a percentage of the compressor 1 corresponding to the instantaneous cooling requirement of the cooling point 6 is determined. Furthermore, an evaluation unit 10 which is in communication with the sensor unit 9 is provided, which determines the percentage opening time F of the valve 7 over a number of time intervals I, the time intervals comprising the current time interval I n and preceding time intervals following thereon. Furthermore, a controller 11 connected to the evaluation unit is provided, which is designed in such a way that the valve 7 is opened for the following time interval I n + 1 when the ratio of the refrigeration requirement corresponding to the percentage power S of the compressor 1 is greater than that is the percentage opening time F of the valve determined for the past, and the valve is closed for the following time interval I n + 1 when the ratio of the refrigeration demand percentage power S of the compressor is less than the historical opening percentage F of the valve is.
Anhand der Fig. 2 wird die Ansteuerung des Ventils 7 anhand eines konkreten Beispiels näher erläutert. Dabei illustrieren die senkrechten, schattierten Balken die Öffnungsstellung (V=100) des Ventils 7. Die dazwischen liegenden weißen Bereiche stellen die Schließstellung (V=0) des Ventils 7 dar. Die Länge eines Zeitintervalls I beträgt bei diesem Ausführungsbeispiel 10s und für die Ermittlung der prozentualen Öffnungszeit F des Ventils 7 werden fünf Zeitintervalle, d. h. das aktuelle Zeitintervall In und die vorhergehenden vier Zeitintervalle (In-1, In-2, In_3, In-4) gebildet. Based on a concrete example, the control of the valve 7 will be explained in more detail with reference to FIG. 2. The vertical, shaded beams illustrate the Opening position (V = 100) of the valve 7. The intermediate white areas represent the closed position (V = 0) of the valve 7. The length of a time interval I in this embodiment is 10 s and for the determination of the percentage opening time F of the valve 7 five time intervals, ie the current time interval I n and the preceding four time intervals (I n-1 , I n-2 , I n _3, I n- 4) formed.
Die prozentuale Öffnungszeit F des Ventils 7 ist mit durchgehender Linie und die dem aktuellen Kältebedarf entsprechende prozentuale Leistung S des Verdichters in gestrichelter Linie eingezeichnet. The percentage opening time F of the valve 7 is indicated by a solid line and the percent cooling capacity S of the compressor corresponding to the current refrigeration demand is shown in dashed line.
Im Fig. 2 dargestellten Ausführungsbeispiel beträgt die dem Kältebedarf entsprechende proportionale Leistung S des Verdichters in den ersten fünf Zeitintervallen L bis I5 = 0%. In den Zeitintervallen I6 bis I20 beträgt die Leistung S = 89% und sinkt dann zunächst auf 30% und später auf 10% ab, bevor sie wieder ansteigt. In the embodiment illustrated in FIG. 2, the proportional power S of the compressor corresponding to the refrigeration requirement in the first five time intervals L to I 5 = 0%. In the time intervals I 6 to I 20 the power S = 89% and then drops first to 30% and later to 10%, before it rises again.
Die Auswerteeinheit 10 ermittelt die prozentuale Öffnungszeit F des Ventils 7 über fünf Zeitintervalle mit der nachfolgend angegebenen Formel: The evaluation unit 10 determines the percentage opening time F of the valve 7 over five time intervals with the formula given below:
mit  With
F: prozentuale Öffnungszeit des Ventils,  F: percentage opening time of the valve,
In: aktuelles Zeitintervall und I n : current time interval and
Vt: Status des Ventils bei einem bestimmten Zeitintervall L (100 = offen oder 0 = geschlossen) V t : status of the valve at a certain time interval L (100 = open or 0 = closed)
Nachdem in den ersten fünf Zeitintervallen kein Kältebedarf an der Kühlstelle vorhanden war, war sowohl die prozentuale Leistung S des Verdichters, als auch die prozentuale Öffnungszeit F des Ventils = 0 und das Ventil war geschlossen. Die nachfolgende Tabelle zeigt den Kältebedarf als prozentuale Leistung S des Verdichters 1 , die prozentuale Öffnungszeit F des Ventils 7 und den Ventilzustand V während der ersten 27 Zeitintervalle des in Fig. 2 dargestellten Beispiels. Mit der obigen Formel wird der Ventilzustand von fünf Zeitintervallen berücksichtigt, die das aktuelle Zeitintervall und die vier zurückliegenden Zeitintervalle umfasst. Nach jedem Zeitintervall verschiebt sich das Zeitfenster um ein Intervall nach unten. In der nachfolgenden Tabelle sind zwei derartige Zeitfenster beispielhaft dargestellt. Since there was no refrigeration demand at the refrigeration point during the first five time intervals, both the percent power S of the compressor and the percent opening time F of the valve were = 0 and the valve was closed. The following table shows the refrigeration demand as a percentage power S of the compressor 1, the percentage opening time F of the valve 7 and the valve state V during the first 27 time intervals of the example shown in FIG. With the above formula, the valve state of five time intervals is considered, which includes the current time interval and the four past time intervals. After each time interval, the time window shifts down by one interval. Two such time windows are shown by way of example in the following table.
Aus der obigen Tabelle ist zu ersehen, dass der Kältebedarf S der Kühlstelle ab dem 6. Zeitintervall 89% beträgt. Da das Ventil zuvor geschlossen war, musste es zum 6. Zeitintervall geöffnet werden. Um die Ventilstellung für das 7. Zeitintervall I7 zu berechnen, wird die obige Formel angewendet. Hierzu wird das aktuelle Zeitintervall I6 sowie die Zeitintervalle bis I5 berücksichtigt (siehe erstes Zeitfenster in der Tabelle). Nachdem das Ventil in diesen fünf Zeitintervallen nur während eines Zeitintervalls geöffnet war, ergibt sich F zu: From the above table it can be seen that the refrigeration requirement S of the refrigeration point is 89% from the 6th time interval. Since the valve was previously closed, it had to 6. Time interval are opened. To calculate the valve position for the 7th time interval I 7 , the above formula is used. For this, the current time interval I 6 and the time intervals up to I 5 are taken into account (see first time window in the table). After the valve has been open during these five time intervals only during a time interval, F results in:
F = 1 * 100 / 5 = 20 % F = 1 * 100/5 = 20%
Nachdem S mit 89 % deutlich größer ist als F bleibt das Ventil im 7. Zeitintervall offen. Erst für das 11. Zeitintervall wird das Ventil geschlossen, da das Ventil seit fünf Zeitintervallen (nämlich vom 6. bis 10. Zeitintervall) geöffnet war und somit die prozentuale Öffnungszeit F des Ventils über die fünf Zeitintervalle 100% beträgt und somit S kleiner als F ist. After 89% is significantly larger than F, the valve remains open in the 7th time interval. The valve is closed only for the 11th time interval since the valve has been open for five time intervals (namely from the 6th to 10th time intervals) and thus the percentage opening time F of the valve over the five time intervals is 100% and thus S less than F is.
Ab dem 21. Zeitintervall beträgt der Kältebedarf S nur noch 30%. Das Ventil wird daher ab dem 21. Zeitintervall wieder geschlossen. Dementsprechend sinkt der Wert F für die prozentuale Öffnungszeit des Ventils über die folgenden Zeitintervalle stetig ab. Für die Ermittlung der Ventilstellung V für das 25. Zeitintervall werden die Zeitintervalle 20 bis 24 ausgewertet (siehe zweites Zeitfenster in der Tabelle), wobei in diesen Zeitintervallen das Ventil nur in einem Zeitintervall, nämlich dem 20. Zeitintervall geöffnet war. Dementsprechend ergibt sich eine prozentuale Öffnungszeit von lediglich 20%> die somit unter dem Kältebedarf S von 30%> liegt. Dementsprechend wird im 25. Zeitintervall das Ventil wieder geöffnet. From the 21st time interval, the refrigeration demand S is only 30%. The valve is therefore closed again from the 21st time interval. Accordingly, the value F for the percentage opening time of the valve steadily decreases over the following time intervals. For the determination of the valve position V for the 25th time interval, the time intervals 20 to 24 are evaluated (see second time window in the table), wherein in these time intervals the valve was open only in a time interval, namely the 20th time interval. This results in a percentage opening time of only 20%> which is thus below the refrigeration requirement S of 30%>. Accordingly, the valve is opened again in the 25th time interval.
Der weitere Verlauf des Kältebedarfs und die jeweiligen Werte für die prozentuale Öffnungszeit F des Ventils und den Ventilzustand V können der Fig. 2 entnommen werden. Dabei ist deutlich zu erkennen, dass der Ventilzustand V keineswegs in jedem Zeitintervall geändert werden muss, wie dies bei einem pulsweitenmodulierten Signal der Fall ist. Wie sich der obigen Tabelle entnehmen lässt, wurde das Ventil in den ersten 27 Zeitintervallen lediglich 8 Mal in seinem Zustand geändert. Dennoch konnte man auf eine Änderung des Kältebedarfs S zu Beginn jedes neuen Zeitintervalls, also spätestens nach 10s, sofort reagieren. Der Kühlmittelstrom durch den Verdichter kann somit zeitnah auf Änderungen des Kältebedarfs der Kühlstelle reagieren. Mit dem erfindungsgemäßen Verfahren wird ein neuer Kältebedarf an der Kühlstelle sogar schneller umgesetzt, da das Ventil solange geöffnet bzw. geschlossen wird, bis der Kältebedarf erreicht ist. Bei einem pulsweitenmodulierten Signal, wird der neue Kältebedarf entsprechend langsamer befriedigt, da das Ventil gleich mit exakt den Öffnung- und Schließzeiten angesteuert wird, dessen Verhältnis dem neuen Kältebedarf entspricht. Der große Vorteil des obigen Verfahrens liegt jedoch in der deutlich reduzierten Schalthäufigkeit des Ventils. Je nach Verlauf des Kältebedarfs der Kühlstelle 6 kann die S ehalt häufigkeit des Ventils bis zu 75% und mehr reduziert werden. Dies wiederum gewährleistet eine entsprechend längere Lebensdauer des Ventils. The further course of the refrigeration requirement and the respective values for the percentage opening time F of the valve and the valve state V can be seen from FIG. It can be clearly seen that the valve state V by no means must be changed in each time interval, as is the case with a pulse width modulated signal. As can be seen from the above table, the valve was changed in its state only 8 times in the first 27 time intervals. Nevertheless, it was possible to respond immediately to a change in the refrigeration demand S at the beginning of each new time interval, ie at the latest after 10 seconds. The coolant flow through the compressor can thus promptly to changes in the refrigeration demand of the cooling point react. With the method according to the invention, a new refrigeration demand at the refrigeration point is implemented even faster, since the valve is opened or closed until the refrigeration requirement is reached. In a pulse width modulated signal, the new cooling demand is satisfied correspondingly slower, since the valve is driven with exactly the same opening and closing times, the ratio of which corresponds to the new refrigeration demand. However, the great advantage of the above method lies in the significantly reduced switching frequency of the valve. Depending on the course of the refrigeration demand of the cooling point 6, the S ehalt frequency of the valve can be reduced by up to 75% and more. This in turn ensures a correspondingly longer life of the valve.

Claims

Patentansprüche claims
1. Verfahren zur Regelung eines einen Motor aufweisenden Verdichters (1) einer Kälteanlage, wobei eine Steuerung den Kältemittelstrom durch den Verdichter (1) über mindestens ein Ventil (7) steuert, wobei das Ventil im Takt von aufeinander folgenden und gleich langen Zeitintervallen (I) entweder im Sinne einer Öffnung oder im Sinne einer Schließung angesteuert wird, sodass das Ventil (7) während eines Zeitintervalls (I) entweder vollständig geschlossen oder vollständig geöffnet ist, wobei a. eine dem momentanen Kältebedarf einer Kühlstelle (6) entsprechende, prozentuale Leistung des Verdichters (1) ermittelt wird, b. eine prozentuale Öffnungszeit (F) des Ventils (7) über eine Anzahl von Zeitintervallen (I), die das aktuelle Zeitintervall (In) und sich daran anschließende vorhergehende Zeitintervalle (In-1, In-2, In_3, In-4) umfassen, ermittelt wird, c. das Ventil (7) für das folgende Zeitintervall (In+i) geöffnet wird, wenn das Verhältnis der dem Kältebedarf entsprechenden, prozentualen Leistung (S) des Verdichters (1) größer als die für die Vergangenheit ermittelte, prozentuale Öffnungszeit (F) des Ventils ist und d. das Ventil (7) für das folgende Zeitintervall (In+i) geschlossen wird, wenn das Verhältnis der dem Kältebedarf entsprechenden, prozentualen Leistung (S) des Verdichters (1) kleiner als die für die Vergangenheit ermittelte, prozentuale Öffnungszeit (F) des Ventils (7) ist. A method of controlling a compressor having a motor (1) of a refrigeration system, wherein a controller controls the flow of refrigerant through the compressor (1) via at least one valve (7), the valve being operated in cycles of successive and equal time intervals (I ) is actuated either in the sense of an opening or in the sense of a closure, so that the valve (7) during a time interval (I) is either completely closed or fully open, wherein a. a percentage of the compressor (1) corresponding to the current refrigeration demand of a refrigeration point (6) is determined, b. a percentage opening time (F) of the valve (7) over a number of time intervals (I) representing the current time interval (I n ) and preceding time intervals (I n-1 , I n-2 , I n _ 3 , I n -4) is determined, c. the valve (7) is opened for the following time interval (I n + i) when the ratio of the refrigeration requirement, the percentage power (S) of the compressor (1) greater than the determined for the past, percentage opening time (F) of the valve is and d. the valve (7) for the following time interval (I n + i) is closed when the ratio of the refrigeration demand, the percentage of power (S) of the compressor (1) smaller than the determined for the past, percentage opening time (F) of the valve (7).
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass das Zeitintervall (I) im Bereich von 2s und 20s verwendet wird. 2. The method according to claim 1, characterized in that the time interval (I) in the range of 2s and 20s is used.
3. Verfahren nach Anspruch 1 , dadurch gekennzeichnet, dass die dem momentanen Kältebedarf einer Kühlstelle (6) entsprechende, prozentuale Leistung (S) des Verdichters (1) im Takt der Steuerung des Ventils (7) ermittelt wird. 3. The method according to claim 1, characterized in that the instantaneous cooling demand of a cooling point (6) corresponding, percent power (S) of the compressor (1) in time with the control of the valve (7) is determined.
4. Verfahren nach Anspruch 1 , dadurch gekennzeichnet, dass das Verhältnis der dem Kältebedarf entsprechenden prozentualen Leistung (S) des Verdichters (1) mit der für die Vergangenheit ermittelten prozentualen Öffnungszeit (F) für jeden Takt des Ventils (7) verglichen wird. 4. The method according to claim 1, characterized in that the ratio of the cooling demand corresponding percentage power (S) of the compressor (1) with the determined for the past percentage opening time (F) for each cycle of the valve (7) is compared.
5. Verfahren nach Anspruch 1 , dadurch gekennzeichnet, dass wenigstens 2 und maximal 7 vergangene Zeitintervalle (I) für die Ermittlung der prozentualen Öffnungszeit (F) des Ventils (7) herangezogen werden. 5. The method according to claim 1, characterized in that at least 2 and a maximum of 7 past time intervals (I) for determining the percentage opening time (F) of the valve (7) are used.
6. Verfahren nach Anspruch 1 , dadurch gekennzeichnet, dass die Dauer des Zeitintervalls (I) einstellbar ist. 6. The method according to claim 1, characterized in that the duration of the time interval (I) is adjustable.
7. Verfahren nach Anspruch 1 , dadurch gekennzeichnet, dass die prozentuale Öffnungszeit (F) des Ventils (7) über eine Anzahl von Zeitintervallen mit der nachfolgend angegebenen Formel ermittelt wird: f = £___! L 7. The method according to claim 1, characterized in that the percentage opening time (F) of the valve (7) over a number of time intervals is determined with the formula given below: f = £ ___! L
m + 1  m + 1
mit  With
F: prozentuale Öffnungszeit des Ventils,  F: percentage opening time of the valve,
In: aktuelles Zeitintervall, I n : current time interval,
m: Anzahl der zu berücksichtigenden, vergangenen Zeitintervalle und  m: number of past time intervals to be considered and
Vt: Status des Ventils bei einem bestimmten Zeitintervall L (100 = offen oder 0 = geschlossen) V t : status of the valve at a certain time interval L (100 = open or 0 = closed)
8. Verdichter (1) einer Kälteanlage mit einem Motor zur Verdichtung eines Kältemittelstroms, 8. compressor (1) a refrigeration system with a motor for compressing a refrigerant flow,
- mindestens einem Ventil (7) zur Beeinflussung der Menge des Kältemittelstroms durch den Verdichter (1) einer Steuereinrichtung (11) zur Steuerung des Ventils (7), wobei das Ventil (7) im Takt von aufeinander folgenden und gleich langen Zeitintervallen (I) entweder im Sinne einer Öffnung oder im Sinne einer Schließung ansteuerbar ist, sodass das Ventil (7) während eines Zeitintervalls (I) entweder vollständig geschlossen oder vollständig geöffnet ist, wenigstens einer Sensoreinheit (9) zur Ermittlung einer dem momentanen Kältebedarf einer Kühlstelle entsprechenden, prozentualen Leistung (S) des Verdichters (1), einer Auswerteeinheit (10) zur Ermittlung einer prozentualen Öffnungszeit (F) des Ventils (7) über eine Anzahl von Zeitintervallen (I), die das aktuelle Zeitintervall (In) und sich daran anschließende vorhergehende Zeitintervalle (I„_i, I„_2, In-3, In-4) umfassen, wobei die Steuereinrichtung (11) mit der Auswerteeinheit (10) in Verbindung steht und derart ausgebildet ist, dass das Ventil (7) für das folgende Zeitintervall (In+i) geöffnet wird, wenn das Verhältnis der dem Kältebedarf entsprechenden, prozentualen Leistung (S) des Verdichters (1) größer als die für die Vergangenheit ermittelte, prozentuale Öffnungszeit (F) des Ventils (7) ist, und das Ventil (7) für das folgende Zeitintervall (In+i) geschlossen wird, wenn das Verhältnis der dem Kältebedarf entsprechenden, prozentualen Leistung (S) des Verdichters (1) kleiner als die für die Vergangenheit ermittelte, prozentuale Öffnungszeit (F) des Ventils (7) ist. - At least one valve (7) for influencing the amount of refrigerant flow through the compressor (1) a control device (11) for controlling the valve (7), wherein the valve (7) is controllable in the cycle of successive and equal time intervals (I) either in the sense of an opening or in the sense of closing, so that the valve (7) during a time interval (I) is either completely closed or fully open, at least one sensor unit (9) for determining a current capacity of a cooling point corresponding percentage power (S) of the compressor (1), an evaluation unit (10) for determining a percentage Opening time (F) of the valve (7) over a number of time intervals (I), the current time interval (I n ) and adjoining preceding time intervals (I "_i, I" _2, I n -3, In-4) comprising, wherein the control means (11) to the evaluation unit (10) is in communication and is configured such that the valve (7) for the following time interval (I n + i) is opened when the Verh ltnis the corresponding to the cooling demand, percentage power (S) of the compressor (1) determined larger than that for the past, percent opening time (F) of the valve (7) and the valve (7) for the next time interval (I n + i ) is closed when the ratio of the refrigeration demand, the percentage power (S) of the compressor (1) is smaller than the determined for the past, percentage opening time (F) of the valve (7).
EP14703391.4A 2013-02-13 2014-02-10 Method for controlling the compressor wit a motor of a refrigeration system and a compressor of a refrigeration system Not-in-force EP2956671B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102013101418.6A DE102013101418B4 (en) 2013-02-13 2013-02-13 Method for controlling a compressor having a motor of a refrigeration system and a compressor of a refrigeration system
PCT/EP2014/052542 WO2014124898A1 (en) 2013-02-13 2014-02-10 Method for controlling a compressor of a refrigeration system, said compressor having a motor, and compressor of a refrigeration system

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EP2956671A1 true EP2956671A1 (en) 2015-12-23
EP2956671B1 EP2956671B1 (en) 2017-03-29

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US (1) US9982928B2 (en)
EP (1) EP2956671B1 (en)
CN (1) CN105026759B (en)
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US6047556A (en) * 1997-12-08 2000-04-11 Carrier Corporation Pulsed flow for capacity control
DE102004048940A1 (en) 2004-10-07 2006-04-13 TEKO Gesellschaft für Kältetechnik mbH Method for controlling the operation of a chiller system has the suction chamber of the piston type compressor periodically isolated by a pulse width modulated control signal
DE102005016433A1 (en) * 2005-04-05 2006-10-12 Bitzer Kühlmaschinenbau Gmbh Refrigerant compressor
US7584625B2 (en) * 2005-10-21 2009-09-08 Emerson Climate Technologies, Inc. Compressor capacity modulation system and method
WO2008018862A1 (en) * 2006-08-08 2008-02-14 Carrier Corporation Suction valve pulse width modulation control based on compressor temperature
JP4861900B2 (en) * 2007-02-09 2012-01-25 サンデン株式会社 Capacity control system for variable capacity compressor
US8151583B2 (en) 2007-08-01 2012-04-10 Trane International Inc. Expansion valve control system and method for air conditioning apparatus
JP2009041547A (en) * 2007-08-10 2009-02-26 Tgk Co Ltd Refrigeration cycle and control valve for variable displacement compressor

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WO2014124898A1 (en) 2014-08-21
DE102013101418A1 (en) 2014-08-14
CN105026759B (en) 2017-03-29
DE102013101418B4 (en) 2015-09-10
US20150316304A1 (en) 2015-11-05
CN105026759A (en) 2015-11-04
EP2956671B1 (en) 2017-03-29
US9982928B2 (en) 2018-05-29

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