MEASURED VALUE STANDARDIZATION

Abstract

The invention relates to a method for controlling and/or monitoring a compressor system comprising several components, namely one or more compressors (11, 12, 13) and one or more peripheral devices (14 to 21), and also a control/monitoring unit (22), wherein the compressors (11, 12, 13) and peripheral devices (14 to 21) are arranged or connected in a certain configuration. The method distinguishes itself in that in a measured-value-capture step, measured values are captured within the compressor system or the components, in an allocation step, context information is allocated to the measured value or measured values in advance, simultaneously, or after the measured-value capture, in order to standardize the measured values, and in an evaluation step, the measured value or measured values standardized by the context information is used in a control, monitoring, diagnostics, or evaluation routine.

Claims

1.-16. (canceled)

17. A method for controlling or monitoring a compressor system, the method comprising: capturing measured values within the compressor system, the compressor system comprising a plurality of components and the measured values generated during operation of the compressor system; allocating context information to the measured values to create standardized measured values, each standardized measured value associating contextual information regarding a meaning of a given measured value within a specific configuration of the plurality of components within a given compressor system to the given measured value; and utilizing at least one of the measured values, at least one of the standardized measured values, or at least one of the measured values and at least one of the standardized measured values to perform tasks in the compressor system.

18. The method of claim 17, wherein allocating further comprises allocating to each standardized measured value a real location within the compressor system where the measured value associated with each standardized measured value is captured.

19. The method of claim 18, wherein allocating to each standardized measured value a real location comprises allocating two or more real locations to one or more standardized measured values.

20. The method of claim 18, wherein each real location is defined directly using a model of the plurality of components of the compressor system.

21. The method of claim 17, wherein the plurality of components comprises compressors and peripheral devices, the peripheral devices comprising filters, dryers, storage devices, air coolers, oil separators, valves, piping and sensors.

22. The method of claim 17, wherein the measured values comprise physical variables, logical variables, comparison data from other compressor systems or ambient data.

23. The method of claim 17, wherein the context information comprises a type of measurement, measurement units, or type of measurement and measurement units.

24. The method of claim 17, wherein the tasks comprise control tasks, monitoring tasks, diagnostics tasks or evaluation tasks.

25. The method of claim 17, wherein standardized measured values can be processed without compressor system-specific adaptations of routines provided for processing measured values.

26. The method of claim 18, wherein the method further comprises defining the real location of each measured value by allocating to each measured value a pre-configured measurement location on a component within the plurality of components wherein linking among components within the plurality of components is not taken into account.

27. The method of claim 18, wherein the method further comprises defining the real location of each measured value by freely configuring a measurement location on a component within the plurality of components to each measured value wherein linking among components within the plurality of components is not taken into account.

28. The method of claim 18, wherein the method further comprises defining the real location of each measured value by allocating to each measured value a pre-configured measurement location on a component within the plurality of components from a basis model of a connection among the plurality of components of the compressor system.

29. The method of claim 18, wherein the method further comprises defining the real location of each measured value by freely configuring a measurement location on a component within the plurality of components to each measured value from a basis model of a connection among the plurality of components of the compressor system.

30. A compressor system comprising: a plurality of components; and a control/monitoring unit, the control/monitoring unit comprising: a measured-value capture unit to capture measured values within the compressor system, the compressor system comprising a plurality of components and the measured values generated during operation of the compressor system; an allocation unit to allocate context information to the measured values to create standardized measured values, each standardized measured value associating contextual information regarding a meaning of a given measured value within a specific configuration of the plurality of components within a given compressor system to the given measured value; and an interface to utilize at least one of the measured values, at least one of the standardized measured values, or at least one of the measured values and at least one of the standardized measured values to perform tasks in the compressor system.

31. The compressor system of claim 30, wherein the plurality of components comprises compressors and peripheral devices, the peripheral devices comprise filters, dryers, storage devices, air coolers, oil separators, valves, piping and sensors.

32. The compressor system of claim 30, the context information comprises a type of measurement, measurement units, or a type of measurement and measurement units.

33. The compressor system of claim 30, standardized measured values can be processed without compressor system-specific adaptations of routines provided for processing measured values.

34. The compressor system of claim 30, wherein the tasks comprise control tasks, monitoring tasks, diagnostics tasks or evaluation tasks.

35. The compressor system of claim 30, wherein the control/monitoring unit defines the real location of each measured value without taking into account linking among components within the plurality of components by allocating to each measured value a pre-configured measurement location on a component within the plurality of components or freely configuring a measurement location on a component within the plurality of components to each measured value.

36. The compressor system of claim 30, wherein the control/monitoring unit defines the real location of each measured value by allocating to each measured value a pre-configured measurement location on a component within the plurality of components from a basis model of a connection among the plurality of components of the compressor system or freely configuring a measurement location on a component within the plurality of components to each measured value from a basis model of a connection among the plurality of components of the compressor system.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0071] The disclosure is explained in more detail below also with respect to additional features and advantages using the description of embodiments and with reference to the accompanying drawings. Shown here are:

[0072] FIG. 1 an exemplary configuration of a compressor system that interacts with the control/monitoring unit according to the disclosure.

[0073] FIG. 2 a basis model that represents the compressor system in its specific given configuration in the form of a P&I schematic.

[0074] FIG. 3 a representation for illustrating an indirectly defined location of a measured-value capture by a name definition.

[0075] FIG. 4 a basis model for defining the context information for a stationary, oil-injected screw-type compressor according to a first variant.

[0076] FIG. 5 an illustration of the allocation of measured values to configured measurement locations of a component, as shown with reference to FIG. 4.

[0077] FIG. 6 a basis model for defining the context information for a stationary, oil-injected screw-type compressor according to a second variant.

[0078] FIG. 7 simplified P&I schematic as a basis model of a stationary, oil-injected screw-type compressor without an add-on dryer.

[0079] FIG. 8 simplified P&I schematic as a basis model of a stationary, oil-injected screw-type compressor with add-on dryer.

DETAILED DESCRIPTION

[0080] In FIG. 1, an example of a configuration of a compressor system is illustrated that interacts with a control/monitoring unit. The illustrated example of the compressor system comprises three compressors 11, 12, 13 arranged parallel to each other. To each compressor 11, 12, 13 a filter 14, 15, 16 is uniquely allocated, which is arranged downstream of the allocated compressor 11, 12, 13. Downstream of the filters 14, 15, 16, two dryers 19, 20 are connected. The compressed air downstream of the first filter should always flow through the first dryer 19. The compressed air downstream of the second filter can be guided by two valves 17, 18 either through the first dryer 19 or through the second dryer 20. The two valves 17, 18 are designed or controlled such that they are never opened simultaneously, that is, when the first valve 17 is open, the second valve 18 remains closed and when the second valve 18 is open, the first valve 17 remains closed.

[0081] Downstream of the two dryers 19, 20 there is a compressed air storage device 21. Downstream of the compressed air storage device 21 there is a pressure sensor 28 for capturing the operating pressure given there.

[0082] To control and/or monitor the compressor system, a control/monitoring unit 22 is provided, which is interactively connected to the compressors 11, 12, 13, as well as to the filters 14, 15, 16, the valves 17, 18, the dryers 19, 20, the compressed air storage device 21, and the pressure sensor 28. The filters 14, 15, 16, the valves 17, 18, the dryers 19, 20, the compressed air storage device 21, and the pressure sensor 28 here form peripheral devices of the compressor system. Together with the compressors 11, 12, 13, these peripheral devices form the components of the compressor system.

[0083] The control/monitoring unit 22 is also in active connection with a memory section 24 and an editor 23. The memory section 24 and/or editor 23 could also, however, be integral parts of the control/monitoring unit 22. The control/monitoring unit 22 can here fulfill control functions, monitoring functions, or control and monitoring functions.

[0084] Monitoring should be understood here to be any form of evaluation, that is, in addition to monitoring for error functions, unusual operating states, alarm situations, etc., also diagnostics, especially in the event of an already present error message, an analysis or evaluation, for example with respect to optimizing or evaluating for predictive maintenance.

[0085] The control/monitoring unit 22 comprises, in the present embodiment, a measured-value-capture unit 25 and also an allocation unit 26, that are here both parts of the control/monitoring unit 22. However, it is also possible to provide, in other embodiments, the measured-value-capture unit 25 completely or partially separate from the control/monitoring unit 22. In addition, it is also possible to provide the allocation unit 26 completely or at least partially separate from the control/monitoring unit 22.

[0086] In the present embodiment, the control/monitoring unit 22 records measured values within the compressor system or within the components during operation of the compressor system or during operation of the components, in the start-up and/or shut-down phases, or in rest states. The measured values can be various data, namely physical variables or variables derived from these or also logical variables, for example values captured by sensors within the compressor system or within the components and/or values captured by sensors outside of the compressor system (e.g., public climate database, ambient air thermometer, measured values of other compressor systems, measured values transmitted from compressed air consumers, etc.) and/or actuator positions and/or ready states of machines and/or operating states and/or control variables.

[0087] With the measured-value-capture unit 25, the control/monitoring unit 22 captures such measured values, whether through actual measurement within the compressor system or through transmission from the components to the control/monitoring unit, whether through targeted polling of individual components within the compressor system or through targeted polling of measured values, for example in databases external to the compressor system or databases allocated in the compressor system. The measured value is unusable as such for a subsequent control, monitoring, diagnostics, or evaluation routine, if its measured value meaning is not defined, that is, context information cannot be allocated to the measured value. For this reason, in the allocation unit 26, the context information is allocated to a measured value, in order to standardize this measured value.

[0088] Such an allocation in an allocation step can take place in advance, simultaneously, or after the measured-value capture. By marking the measured value with context information, this data pair can be taken into account as a standardized measured value in the subsequent control, monitoring, diagnostics, or evaluation routines. The context information defines an allocation of the location of a measured-value capture and/or the medium that the measured value refers to.

[0089] In one specific preferred embodiment, for the allocation of the location of the measured-value capture and/or the medium that the measured value refers to, one or more basis models of the specific compressor system or comparable compressor systems are taken into account. The obtained measured value can be handled meaningfully only if the context in which the measured value was determined is known.

[0090] The compressor system according to FIG. 1 can be described, for example, in a P&I schematic according to FIG. 2. In this respect, the P&I schematic according to FIG. 2 forms a basis model for the compressor system according to FIG. 1, by defining the active relationships within the compressor system. If a measured-value capture is positioned within such a model, as the P&I schematic according to FIG. 2 defines, the context information of the measured value is clear and defines, in this respect, the meaning of the measured value.

[0091] Although a basis model in the form of a P&I schematics, as is reproduced in FIG. 2 for the compressor system according to FIG. 1, an especially suitable model is defined, in order to give the most precise context information possible for a measured value, weaker context information that codes the location of the measured-value capture is also conceivable and expedient. A first conceivable coding could take place by a name definition if this name definition is sufficiently clear.

[0092] This shall be explained below with reference to FIG. 3. For example, if the manufacturer KAESER has determined that PN shall always designate the machine discharge pressure, then the location of the measured-value capture is directly determined by this name definition, therefore the context is defined for the measured value pressure.

[0093] In FIG. 3, two variants for compressors are shown that comprise first an inlet valve 29, a compressor block 30 with a screw-type compressor, and downstream of the compressor block 30 an oil separator 31, which forwards the heated compressed air to an air cooler 32. An oil circuit 33 feeds oil for cooling the compressor block 30 and for guaranteeing a lubricant film on the screw in the compressor block, wherein the oil mixed with compressed air and generated under pressure is fed back in the already mentioned oil separator 31 and returned to the compressor block 30, wherein a partial flow adjustable by a temperature valve 34 can be guided via an oil cooler 35 for reducing the oil temperature. The two compressors shown in FIG. 3 with reference to a P&I schematic differ in that the compressor shown above is equipped without an internal add-on dryer 36 (variant A), the compressor shown below, however, is equipped with an internal add-on dryer 36 (variant B).

[0094] Indeed, by the name convention, it is now determined that PN designates the machine discharge pressure; but whether the compressed air was first guided through an add-on dryer 36 of the compressor (variant B) or not (Variant A) cannot be derived via this name convention.

[0095] In this respect, it is useful to also code the P&I schematic of the compressor—at least along general lines—in more precise context information of the measured value captured on the pressure sensor 28, so that, with reference to this model-based information, it is clear whether the pressure captured on the pressure sensor 28 measures compressed air that flows through an add-on dryer 36 (variant B) or is discharged by the compressor without add-on dryer 36 (variant A).

[0096] In FIG. 4, a simplified model for defining the context information for a stationary, oil-injected screw-type compressor is shown, wherein here the interactions between the individual elements of the compressor block 30, oil separator 31, air cooler 32, input 37, output 38 are not defined. With respect to the element compressor block 30, the pressure and temperature can be captured both on the suction side and also on the pressure side (Tsuction, Psuction, VET, Ppressure), In contrast, for the oil separator 31, only the capture of a pressure (Pi), but not, e.g., the capture of a temperature, is provided for.

[0097] The standardization of the meaning of measured values takes place only in that one or more measurement locations in the model for standardizing the meaning of measured values is allocated to a measured value.

[0098] The basic principle is shown with reference to FIG. 5. The measured values captured for a component are standardized—at the latest after a first measured value preparation—with respect to the content, so that the physical variable type (pressure, temperature, etc.) and the unit (Pa, K, etc.) are also known. Context information should now be allocated to the measured values, pressure 1, pressure 2, temperature 1, prepared in a first step. Here, the basis model of a component, in reality the stationary, oil-injected screw-type compressor according to FIG. 4 is used in which basically for these components, namely a stationary, oil-injected screw-type compressor without an add-on dryer, it is defined which measurement locations are basically predefined. These are each reproduced in FIG. 5 in the “context information” field. Now the measured value or measured values, specifically pressure 1, pressure 2, temperature 1 are allocated to a measurement location predefined in the basis model of the component according to FIG. 4, wherein this allocation is here specifically realized by a connecting line between each measured value and the context information. Through this allocation of the measured value to a provided measurement location in the basis model, the meaning of the measured value with respect to the context is now defined.

[0099] Here it must be noted that a measured value can also be allocated to two measurement locations (here illustrated using the example of “Pressure 2”). For a multiple allocation of one measured value to measurement locations, a sub-meaning for a measured value must be shown (here, specifically: “Pressure downstream of the air cooler” and “Machine output pressure”). This type of context information is necessary in many cases, because, in reality, one measurement location can also sit between two components (and thus have a relationship to both components). However, if a basis model according to FIG. 4 is used as the basis, then the interactions between the components are not modeled.

[0100] The method explained with reference to FIG. 4 for standardizing the meaning of measured values has the limitation that only measurement locations that were preconceived in the basis model according to FIG. 4 (variable type on certain connection of a component) can be used for the standardization of the meaning of measured values. To soften this limitation, the method can further provide that some measurement locations can be defined in basis models of components, in order to use these for the standardization of the meaning of measured values. For this definition of context information it should be further noted that the components are defined in advance and the linking of the components is not considered.

[0101] In one improvement of the standardization of the measured values, a basis model for a component according to FIG. 6 will now be referenced, in which not only the individual elements of the component itself are defined, but also the linking between the individual elements is defined. As an specific example for a corresponding basis model, a stationary, oil-injected screw-type compressor without add-on dryer was referenced here.

[0102] The pre-defined measurement locations in the basis model are specified again. The measurement locations correspond to the measurement locations in FIG. 4. However, in the basis model that now also codes the interactions of the individual elements, the information already includes that .sub.Pcold=.sub.PN and thus .sub.Pcold can be eliminated as a pre-configured measurement location. The allocation step for individual measured values can then be performed as described with reference to FIG. 5 in connection with the basis model according to FIG. 4.

[0103] In another stage of expanding the basis model according to FIG. 5, it is possible to freely configure the measurement locations for a variable type on certain connections of an element.

[0104] The definition of a measurement location and the allocation of captured measured values to a measurement location within a basis model were previously explained with reference to the example of a stationary, oil-injected screw-type compressor without add-on dryer. It is self-explanatory that this procedure can also be transferred to any other component of a compressor system or to the compressor system itself. If the basis model according to FIG. 4 for an individual component is transferred to the entire compressor system, then essential or all components of a compressor system are defined without their specific interactions. Pre-configured measurement locations at the individual components were predefined for different measurement variables. Context information could be allocated in the same way to each captured measured value. Obviously it is also possible to provide in one modification not only pre-configured measurement locations on the individual components of a compressor system, but also to allow that corresponding measurement locations can be freely configured.

[0105] In a modified embodiment, however, for a compressor system not only the essential or all components are defined, but also the interactions between the components are known, for example with reference to a P&I schematic, as illustrated with reference to an example of a compressor system according to FIG. 2. In this case, pre-configured measurement locations can also be defined in a corresponding basis model. In another modification, however, it is also possible that such measurement locations can be freely configured within the basis model. It is decisive that for each captured measured value, specific context information can be allocated with reference to such basis models.

[0106] There are basically many different uses for standardized data. Standardized measured data can be used, for example, [0107] to be able to specify a starting value for the first simulation step in simulation models, [0108] to compare real measured data with data derived via a model in a diagnostics routine, [0109] to conduct analyses about the reliability of individual components or the entire compressor system, for example from the aspect of energy consumption, [0110] a prediction for performing the next maintenance measures under the most accurate measured data possible from the past, etc.

[0111] As a whole, for the analysis not dependent on the individual case of measured data captured from the field (sensor values, characteristic values, etc.), it is a prerequisite that a well-defined meaning and optionally a well-defined unit (e.g., temperature in ° C. or pressure in Pa) are allocated to each data point. If meaning and/or unit of a data point are unknown, then an analysis, apart from statistical analyses, is basically impossible. In particular, analysis results cannot be interpreted. Through the use of domain-specific models it is possible to allocate a well-defined meaning with respect to one or more aspects to the measured data. This happens in that, with reference to a domain-specific model, the location of the measured-value capture is defined. Through the analysis of the domain-specific model, the meaning of a data point can then be determined.

[0112] This becomes clear when the P&I schematic of a stationary, oil-injected screw-type compressor without add-on dryer (see FIG. 7) is compared with the P&I schematic of a stationary, oil-injected screw-type compressor with add-on dryer (see FIG. 8). In both compressors, the same number of sensors is installed. The sensors are also named identically. Just from the naming of the sensors, however, no meaning can be derived. This becomes clear with the sensor that supplies the measured value Tout• In the compressor without add-on dryer, the sensor has the meaning “temperature downstream of the air cooler” and “temperature at the output of the compressor.” In the compressor with add-on dryer, the sensor has the meaning “temperature downstream of the dryer” and “temperature at the output of the compressor.” This difference in meaning is relevant for the analysis. The allocation of the corresponding context information via a defined basis model is decisive, in this respect, to be able to use captured measured values in other control, monitoring, diagnostics, or evaluation routines.

[0113] As described above, it is relevant to know the meaning of the measured values at the latest at the time of the analysis. For many applications, however, it is not necessary to know the meaning of a measured value at the time of the measured-value capture. The information on [0114] the time value profile of a measured value and [0115] the meaning of a measured value
can be captured and stored separately from each other. “Separately” can here be understood to mean both chronologically and also spatially (individually and combined). As examples, the following scenarios will be given:

[0116] Using a basis model of the compressor system involving a P&I schematic and several basis models of the components of the compressor system involving P&I schematics, the measured value meaning or the context information of the measured values captured by the control/monitoring unit is stored in the control/monitoring unit or externally, for example in a memory section 24. The storage of the context information (measured value meanings) happens, e.g., during the commissioning of the compressor system or during the commissioning of the control/monitoring unit. The context information (measured value meanings) can be stored, e.g., in the form of a table in the control/monitoring unit.

[0117] The measured values captured by the control/monitoring unit are stored in the control/monitoring unit typically as a process image (specific values) and as process data history (historical values). The storage can (but does not have to) take place without context information (information on the measured value meaning), because the context information is available at any time in the control/monitoring unit and the measured values can be allocated to a desired time. The allocation of context information to a measured value takes place in one possible embodiment by an allocation table. The allocation table stores what context information is allocated to the measured values. Here, one and the same measured value can simultaneously have multiple (consistent) meanings, and one and the same meaning can obviously be connected to several measured values.

[0118] Double assignment of measured value meanings can be useful if the reliability or the accuracy of the measured-value capture is to be increased. For example, if one of two sensors for the measured-value capture fails, the measured value of the other sensor can be used for further processing. If the measured values of both sensors that eventually generate measured values with the same measured value meaning are available, then by calculation (average value, maximum value, minimum value calculation) the accuracy of the measured-value capture can be increased.

[0119] Before measured values are processed, if it has not already taken place during storage, measured values and context information (measured value meanings) are joined. By joining the measured values and context information, with the help of the models that were used for defining the context information, an automatic evaluation is possible. For the evaluation, analysis routines are used.

[0120] If the analysis routines run in the control and monitoring unit or if the system that executes the analysis routines is connected in terms of data to the control and monitoring unit, then automatic evaluation is also possible in real time.

[0121] With regard to the development of basis models for compressor systems, refer to EP 13159618.1 that is herewith referenced in full. At the same time, the data standardized according to the present disclosure could also contribute to refining the definition of interactions between components of a compressor system defined in EP 13159618.1 in the form of a P&I schematic.

[0122] The data standardized according to the present disclosure can also be used in models derived during development, such as those in EP 13159616.5, which is hereby referenced in its full extent.

[0123] Although the disclosure has been described using a compressor system, even for over pressure, all of the principles can be transferred to a vacuum system that acts with pumps instead of compressors.