Method for operating a flow-generating system and flow-generating system

Abstract

The invention relates to a method for operating a flow generation system (10) and to a flow generation system (10) configured to carry out the method. The flow generation system (10) has at least one flow generation group (12), each comprising a plurality of flow generation units (11). The flow generation units (11) can be, for example, fans (14). The flow generation units (11) of a common flow generation group (12) are fluidically connected to a common flow space (13) and controlled by means of a control device (17), to which at least one target parameter (PG) is specified for control or regulation. At least one flow generation unit (11) from the flow generation group (12) is selected, and an individual target operating state (BSi) is determined in each case.The determined target operating state (BSi) is checked for admissibility for steady-state operation using an individual operating limitation (LIM). If necessary, two or more target operating states (BSi) are changed until all target operating states (BSi) of the selected flow generator units (11) are permissible.

Description

[0001] The invention relates to a method for operating a flow generation system and to a flow generation system with a control device configured to carry out the method. The flow generation system has at least one flow generation group with a plurality of flow generation units, which can be controlled by the control device. Each flow generation unit is configured to generate an individual fluid flow. The fluid flow can be a gas flow or a liquid flow. Preferably, the flow generation unit is designed as a fan or has a fan and is configured to generate an air flow.

[0002] EP 3 749 864 A1 discloses a method for determining the operating states of a fan, an arrangement of multiple fans, fan groups, or fan systems. The individual fans of a fan arrangement can be operated in a coordinated manner. A digital image of the actual fan is generated using mathematical calculation models and known data, such as measurement data, which represents the operation of the actual fan. The aim is to achieve predictive maintenance with the goal of achieving the maximum possible service life. Critical system states, such as resonances or excessively high temperatures, are to be avoided.

[0003] In practice, it is often difficult to predict changes in a flow generation system that occur over time. Therefore, the object of the present invention is to provide a method and a flow generation system that provide optimized operation of a flow generation group comprising multiple flow generation units, taking into account aging effects or other changes that occur over time.

[0004] This object is achieved by a method having the features of patent claim 1 and a flow generation system having the features of patent claim 11.

[0005] The flow generation system comprises a control device for controlling a flow generation group comprising a plurality of flow generation units. Each flow generation unit is configured to generate an individual fluid flow. The fluid flow may be a liquid flow, but is preferably a gas flow, in particular an air flow. For this purpose, in one embodiment, the flow generation units belonging to a flow generation group are designed as fans or each have a fan. The flow generation units of a common flow generation group are fluidically connected to a common flow space, so that their individual fluid flows can form an overall fluid flow for the common flow space.

[0006] The control device according to the present invention can preferably comprise a plurality of communicatively connected local control units. A local control unit is preferably assigned to a single flow generator unit. For example, a flow generator unit can comprise a controllable electric motor, and the local control unit can be the motor controller of the electric motor. In addition to or alternatively to the local control units, the control device can comprise a higher-level controller or be a higher-level controller that is communicatively connected to the flow generator units. Such a higher-level controller can be, for example, a central server and / or an internet service (cloud service).

[0007] Preferably, the flow generator units (e.g., the local control units) are connected wirelessly and / or wired to a communications network and can therefore communicate with each other. Optionally, the higher-level controller can be connected wirelessly and / or wired to a communications network.

[0008] The control device specifies a target parameter for the flow chamber or its atmosphere, such as a target pressure, a target temperature, a target humidity, a target flow velocity for the overall fluid flow, or a target volume flow for the overall fluid flow. It is also possible to specify multiple target parameters in any combination. Multiple parameters can also be controlled or regulated using the flow generator group, as the multiple flow generator units provide a degree of freedom for this.

[0009] Within the framework of the process, individual operating limitations are repeatedly determined for each flow generator unit in the flow generator group with increasing operating time. The operating limitation of a flow generator unit is, in particular, an operating state of the flow generator unit within the type-specific permitted nominal operating limits, which is, however, unsuitable for steady-state operation of the respective flow generator unit, for example, because resonance vibrations occur in this operating state. An individual operating limitation can also be an operating state in which the flow generator unit in question does not achieve a specified minimum efficiency.

[0010] The determination of the current individual operating limit is performed repeatedly, for example, in a time-controlled manner at predetermined time intervals and / or event-controlled depending on an event, for example, when at least one target parameter to be set is changed. The time interval and / or the times and / or the timing for the repeated determination of the current individual operating limit can be defined individually for each flow generator unit, for example, depending on the previous total operating time of the flow generator unit in question.

[0011] To control or regulate the atmosphere in the flow space according to the specified, at least one target parameter, one flow generator unit or several or all flow generator units are selected from the flow generator group and an individual target operating state is determined for each selected flow generator unit. The individual target operating states of the selected flow generator units are determined in such a way that, overall, the joint operation of the flow generator units allows the at least one target parameter to be achieved (controlled or regulated) as accurately as possible. When determining the individual target operating states, the individual operating limitations of the selected flow generator units are taken into account in order to avoid stationary operation in an operating state that is unsuitable for this purpose.

[0012] This allows an optimized interaction of the flow generator units of a flow generator group to be achieved.

[0013] If, for example, the initially determined individual target operating state for a flow generator unit results in an operating state that is unsuitable for steady-state operation due to the individual operating limitation, the flow generator unit in question can select a different, modified individual target operating state that avoids the individual operating limitation in question and, in particular, corresponds as closely as possible to the initially determined individual target operating state. This adjustment is transmitted to the other selected flow generator units so that one or more of the additional flow generator units can also adjust their respective target operating state in order to achieve the common control objective or regulation objective defined by the at least one target parameter.This approach is an embodiment in which each selected flow generator unit avoids stationary operation in an operating state that is to be avoided by an individual operating limitation, which can also be realized without a higher-level control by the flow generator units coordinating with each other.

[0014] Additionally or alternatively, the composition of the selected flow generator units can also be varied to take into account the individual operating limitations of the flow generator units used to achieve the control or regulation objective.

[0015] In all embodiments, the control device can preferably be configured for machine learning. It can comprise components of machine learning and / or artificial intelligence (AI). Components here are understood to mean devices and / or processes and / or methods that can be present or used in the control device. Machine learning can be any form of machine learning, in particular supervised machine learning, unsupervised machine learning, reinforcement machine learning, etc. Within the scope of machine learning, methods for pattern recognition, pattern analysis, or pattern prediction can be used.

[0016] An artificial intelligence component (AI component) can be any known implementation of an AI component, such as an artificial neural network or a support vector machine (SVM).

[0017] Machine learning and / or artificial intelligence are particularly effective at determining updates to the individual operating limitations of the flow generator units. Furthermore, adjustments to the target operating states and / or the selection of the flow generator units intended for operation can be implemented very effectively using machine learning and / or AI, particularly because very targeted adjustments can be made to avoid individual operating limitations. The control or regulation target can therefore be set sufficiently quickly.

[0018] It is preferred if each flow generator unit is continuously monitored or tested and the individual operating limit is determined. Optionally, it would also be possible for each flow generator unit to be operated in a predetermined test mode to determine its individual operating limit. To test or determine its individual operating limit, the at least one flow generator unit in question can be operated in particular in several different operating states of the flow generator unit. The test or determination of the individual operating limit can - as explained - be initiated at regular time intervals in a time-controlled and / or event-controlled manner. For example, the electrical and / or mechanical power of the flow generator unit can be varied.In one embodiment, at least one operating parameter of an electric motor of the flow generator unit is varied, for example the speed, the torque, the motor current, the motor voltage, the electrical power or any combination thereof.

[0019] In general, during the testing or determination of the individual operating limitation, an operating and / or flow parameter of the individual fluid flow generated by the flow generator unit can be determined as a monitoring parameter, and it can be checked whether this monitoring parameter lies within a permissible range, for example, whether it does not fall below or exceed at least a predetermined minimum and / or maximum limit value. In one embodiment, the monitoring parameter is a vibration parameter. The monitoring parameter can alternatively also be a temperature, a motor current, an electrical power, an efficiency of the flow generator unit, a volume (e.g., a sound power level and / or a sound intensity level), or the like.

[0020] For example, using a noise level parameter as a monitoring parameter can be used to optimize system operation with regard to noise emissions. For example, in terms of overall noise, it may be better to operate several fans with lower power or speed than one or fewer fans with comparatively higher power or speed.

[0021] The monitoring parameter can be either directly measured or determined by other means. For example, it can be determined based on at least one measured value by calculation, estimation, or simulation.

[0022] During testing or determination of the individual operating limitation, in particular the speed of the electric motor of the flow generator unit can be varied in at least one predetermined test speed range within the nominal speed range or across the entire nominal speed range in order to determine one or more speeds or speed ranges in which resonant vibrations occur. The test speed range can be a speed range in which a resonant vibration or another undesirable condition (e.g. excessively high temperature, poor efficiency, etc.) is expected. The speed can be varied continuously or stepwise between a minimum speed and a maximum speed in the test speed range. The at least one test speed range can be a sub-range of the entire permissible speed range (nominal speed range) or comprise the entire nominal speed range.

[0023] A speed at which a resonant vibration has been detected can then represent an operating limitation that specifies that the flow generator unit should not be operated in a steady state at the speed causing the resonant vibration. Briefly reaching this speed during a speed change (e.g. with a speed gradient other than zero) is permitted. Only steady state operation for a specified minimum period of time, for example at least 10 seconds, at least 30 seconds or at least 1 minute, is prevented by the operating limitation. The operating limitation can exclude a speed range in which the speed of the electric motor lies at which the resonant vibration was detected.

[0024] To determine a vibration parameter as a monitoring parameter, a vibration sensor can be used, for example, which measures the vibration of the electric motor or another component of the flow generator unit and / or a device vibrationally coupled to the flow generator unit. Such a vibration-coupled device can be, for example, a guide device for the generated individual fluid flow. An acceleration sensor and / or a microphone can be used as the vibration sensor. The vibration can be any vibration, for example, a harmonic or non-harmonic vibration. The frequency and amplitude of the vibration vary, in particular, depending on the operating state of the flow generator unit.

[0025] It is advantageous if the downtime of a non-selected or each non-selected flow generator unit is recorded. The downtime can be compared to a maximum duration. If the downtime exceeds the maximum duration, the flow generator unit in question can be put into operation at least briefly or temporarily to test its functionality. For example, a currently selected, operated flow generator unit can be at least temporarily shut down and / or its power reduced, and the idle, non-selected flow generator unit can be put into operation at least temporarily, such that the specified control or regulation objective is still achieved.This can prevent a situation where, due to longer downtimes, an impairment such as heavy contamination, icing, damage or the like is not detected and the flow generator unit in question is then not available when required.

[0026] If a fault is detected in a flow generator unit, either by the local control unit of the affected flow generator unit or another local control unit or a higher-level control of the control system, the affected flow generator unit can be taken out of service for maintenance, repair, or servicing. Ideally, the control or regulation objective can still be achieved with the remaining available flow generator units, provided this does not require all available flow generator units to operate at maximum power. The flow generator group therefore also provides redundancy in the event of a failure.

[0027] In a preferred embodiment, a total operating time of each individual flow generator unit of the flow generator group is recorded. The total operating time is the duration during which the flow generator unit in question was operated from the time of initial commissioning. In addition to or as an alternative to the total operating time, another total operating characteristic can also be recorded, which takes into account not only the duration but also the respective power. When selecting the flow generator units to be operated in order to achieve the control or regulation objective specified by the at least one target parameter, the preferred embodiment takes into account those flow generator units whose total operating characteristic indicates a lower load, for example a lower total operating time and / or a lower cumulative total power provided during the entire operating time.This allows the wear and load on the flow generator units of the flow generator group to be as uniform as possible, which can increase the overall service life of the flow generator group.

[0028] In a preferred embodiment, each flow generator unit has a controllable electric motor and a rotor connected to the electric motor for driving purposes, in particular a fan rotor, which can also be referred to as an impeller or fan wheel. In particular, each flow generator unit has exactly one electric motor and, more preferably, exactly one local control unit. In particular, each local control unit is a motor controller for the electric motor. A higher-level controller (central server, internet service) is optional. As explained, the local control units can be communicatively connected and coordinate their operation with one another.

[0029] Instead of a fan rotor, a flow generator unit can also have a pump rotor driven by the electric motor, so that a motor-pump unit is formed.

[0030] Advantageous embodiments of the invention will become apparent from the dependent claims, the description, and the drawings. Preferred embodiments of the invention are explained in detail below with reference to the accompanying drawings. The drawings show: Figure 1 a block diagram of an embodiment of a flow generation system, Figure 2 a block diagram of a flow generator unit of the flow generation system from Figure 1 , Figure 3 a flowchart of an embodiment of a method for operating the flow generation system, Figure 4 a flowchart of several method steps of an embodiment of the method from Figure 3, Figure 5an exemplary representation of a speed n of an electric motor of a flow generator unit during a test or determination of the individual operating limitation and Figure 6 an exemplary representation of a monitoring parameter in the form of a vibration parameter, which is used in the context of Figure 5 The test of a flow generator unit shown is determined and evaluated.

[0031] Figure 1shows, in a schematic block diagram-like representation, a flow generation system 10 with several flow generator units 11, which together form a flow generator group 12. The flow generator units 11 of a common flow generator group 12 are fluidically connected to a common flow space 13. Each flow generator unit 11 is configured to generate an individual fluid flow F, which in the exemplary embodiment is an air flow L. According to the example, each flow generator unit 11 is implemented as a fan 14.

[0032] The flow generation system 10 has a control device 17 for controlling the flow generator group 12 or the associated flow generator units 11. The control device 17 can be or have a higher-level controller 18 that is communicatively connected to the flow generator units 11. Additionally or alternatively, the control device 17 can have a plurality of local control units 19, wherein, in particular, each flow generator unit 11 has an individual local control unit 19. The higher-level controller 18 is optional in this case and can be omitted.

[0033] The individual fluid flows F of the flow generator units 11 interact in the flow chamber 13 and generate a total fluid flow GF there. The flow chamber 13 can, for example, be a room in a building. The flow generation system 10 can, for example, be part of a system installed in or on the building, such as a ventilation system, an air conditioning system, a heating system, or a cooling system. The flow generator units 11 can be connected to the flow chamber 13 on the pressure side or the suction side, as shown schematically in Figure 1 The number of flow generator units 11 in a single flow generator group 12 can vary. Each flow generator group 12 has at least two or three flow generator units 11 and, for example, fans 14.

[0034] A target parameter PG to be set for the atmosphere in the flow space 13 is specified to the control device 17. The at least one target parameter PG to be set thus defines the control or regulation objective for the flow space 13 or for the flow generator group 12. This control or regulation objective is to be achieved through the interaction of the individual fluid flows F. For this purpose, the operation of the flow generator units 11 of the flow generator group 12 is coordinated by the control device 17 (several local control units 19 and / or higher-level controller 18). For this purpose, the local control units 19 are each connected to a common communication network 21 via a local communication interface 20 to form the control device 17. The communication connection between the local control units 19 or the flow generator units 11 can be wireless and / or wired.Optionally, several flow generator groups 12 of a flow generation system 10 can also be connected to the communication network 21, provided that the flow generation system 10 has several flow generator groups 12.

[0035] In all embodiments, the control device 17 (multiple local control units 19 and / or higher-level controller 18) can comprise machine learning and / or artificial intelligence (AI) components. Components here refer to devices and / or methods and / or methods that can be present or used in the control device 17.

[0036] The flow generation system 10 can have at least one sensor 25. Each sensor 25 is configured to provide a measured value that describes either the total fluid flow GF and / or the atmosphere in the flow space 13 and / or an individual fluid flow F and / or an operating state of a flow generator unit 11 or a fan 14. The sensor 25 or at least one of the existing sensors 25 can be a local sensor and be communicatively connected to a local control unit 19. The local sensor 26 makes the respectively acquired measured value available to the local control unit 19. The local control unit 19 can optionally make the measured value available to other flow generator units 11 via the communication network 21.

[0037] Additionally or alternatively, the sensor 25 or at least one of the existing sensors can be a system sensor 27 that is communicatively connected to several local control units 19 and in particular to the communication network 21, so that the measured value of a system sensor 27 is available to several or all flow generator units or local control units 19. In particular, the system sensor 27 is configured to detect a measured value in the atmosphere of the flow space 13 and / or a measured value of the total fluid flow GF. This makes it possible, for example, to achieve control of the at least one desired parameter PG to be set.

[0038] The number of sensors 25 can vary depending on the specific application.

[0039] The at least one system sensor 27 can be configured to detect one or more of the following parameters: a temperature in the flow space 13, a pressure in the flow space 13, a flow velocity of the total fluid flow GF in the flow space 13 and / or a volume flow of the total fluid flow GF in the flow space 13. Each parameter can be detected at a single measuring point in the flow space 13 or at several measuring points arranged at a distance from one another in the flow space 13 by a respective system sensor 27.

[0040] In Figure 2The structure of a flow generator unit 11 or a fan 14 according to a preferred embodiment is shown. The fan 14 has a controllable electric motor 30, which is drive-connected to a fan rotor 31, so that the air flow L is generated upon rotation of the fan rotor 31. The electric motor 30 is controlled by the local control unit 19. The control unit 19 is preferably the motor controller of the electric motor 30 and can form a common assembly with the electric motor 30.

[0041] As exemplified in Figure 2As shown, the flow generator unit 11 can have one or more local sensors 26. For example, an operating parameter of the electric motor 30 can be detected by means of at least one local sensor 26. One or more of the following parameters can be determined in any combination as operating parameters of the electric motor 30: a motor current, a motor voltage, a rotational speed, a temperature and / or a vibration of the electric motor 30. Additionally or alternatively, a local sensor 26 can detect a parameter of the generated fluid flow F and, for example, the air flow L, wherein one or more of the following parameters can be detected in any combination: a pressure, a flow velocity, a volume flow and / or a temperature of the individual fluid flow F.

[0042] In the exemplary embodiment, the flow generator unit 11 has a data memory 33 that is communicatively connected to the local control unit 19 or the motor controller 32. The data or parameters required to control the electric motor 30 can be stored in the data memory 33.

[0043] The flow generation system 10 explained so far and in particular the flow generator units 11 of a common flow generator group 12 are operated in a coordinated manner, as can be seen from the Figure 3 The procedure V shown as an example is explained below.

[0044] At least one target parameter PG is specified for the flow chamber 13. This specification can be made, for example, via an operator interface in or on the flow chamber 13 and / or another device that is communicatively connected to the communication network 21, such as a gateway or the higher-level controller 18 (first method step V1).

[0045] In a second method step V2, one, several, or all flow generator units 11 are selected from the flow generator group 12 to be operated in order to adjust the at least one target parameter PG and thus achieve the specified control or regulation objective. For each selected flow generator unit 11, an individual target operating state BSi (i=1, 2, 3, ...) is determined, resulting in a total fluid flow GF for the flow space 13 in order to fulfill the specifications of the at least one target parameter PG.

[0046] When selecting the flow generator units 11 and determining the individual target operating states BSi, operating limitations LIM of the selected flow generator units 11 are taken into account, whereby each operating limitation LIM is determined individually for the assigned flow generator unit 11 and can be stored, for example, in the data memory 33. The determination of the individual operating limitation LIM for each flow generator unit 11 is carried out repeatedly from the time of commissioning of the flow generation system 10 with increasing operating time, for example, in a time-controlled manner at predetermined (e.g., regular) time intervals and / or event-controlled. Thus, the individual operating limitation LIM for each flow generator unit 11 is always up-to-date.

[0047] The operating limitation LIM of the flow generator unit 11 specifies the operating states in which the respective flow generator unit 11 should not be operated in a stationary manner to avoid excessive wear, excessive loads, or damage. For example, the operating limitation can be used to exclude one or more of the following operating states for the assigned flow generator unit 11: an operating state, in particular a speed n of the electric motor 30, in which a resonant oscillation occurs; an operating state in which a temperature of the electric motor 30 or the local control unit 19 exceeds a temperature limit value; an operating state in which the flow generator unit 11 or the fan 14 falls below a minimum efficiency; an operating state in which an operating noise of the flow generator unit 11 exceeds a predetermined limit value, an operating state in which a defined power limit value (e.g. permissible maximum power in continuous operation) is exceeded.

[0048] In the second method step V2, the selected flow generator units 11 are coordinated with one another in such a way that their target operating states are each outside the operating limitation and the control or regulation objective specified by the at least one target parameter can be achieved overall.

[0049] Subsequently, in a third method step V3, the selected flow generator units 11 are operated according to the determined target operating state BSi.

[0050] If not all flow generator units 11 of a flow generator group 12 are selected and operated for a current operation, one or more flow generator units 11 may be idle. The idle time of each flow generator unit 11 is recorded and compared with a maximum duration. If the idle time during which the flow generator unit 11 in question is idle without interruption exceeds the maximum duration, it can be put into operation at least temporarily, for example, to test its functionality. This can prevent a flow generator unit 11 that has been idle for an extended period from being undetectedly impaired in its function.For example, in this context, a selected currently operating flow generator unit 11 can have its output reduced or be shut down, and a previously idle flow generator unit 11 can be operated as a replacement to replace the reduced or shut down flow output. This makes it possible to determine whether all flow generator units 11 of a flow generator group 12 are functional.

[0051] Due to the resulting degrees of freedom or redundancy of the multiple flow generator units 11 of the common flow generator group 12, other boundary conditions can also be taken into account to optimize the flow generator system 10. For example, one boundary condition that can be taken into account is to distribute the load or wear of the flow generator units 11 as evenly as possible. For this purpose, an overall operating characteristic value can be determined for each flow generator unit 11. The overall operating characteristic value of an assigned flow generator unit 11 describes the load that has occurred since its commissioning. In the simplest case, the overall operating characteristic value can be the total operating time of the flow generator unit 11. In addition to the total operating time, the electrical and / or mechanical power set during the operating phases of the flow generator unit 11 can optionally also be taken into account.For example, a performance value (e.g., energy) accumulated over the entire operating period can be determined as the overall operating characteristic. Optionally, different performance ranges of the flow generator unit 11 can be weighted differently, so that, for example, loads on the flow generator unit 11 in a maximum performance range are included in the overall operating characteristic with a higher weighting than operating phases with medium or lower performance in the nominal performance range of the respective flow generator unit 11.

[0052] Based on the overall operating characteristic value, those flow generator units 11 for which the respective overall operating characteristic value indicates a lower load can be prioritized during the selection and / or determination of the individual target operating states BSi. Thus, the flow generator units 11 can be selected in order of their assigned overall operating characteristic values, starting with the overall operating characteristic value that indicates the lowest load, for example, the smallest overall operating characteristic value. Starting from this flow generator unit 11, any additional flow generator units 11 required from the flow generator group 12 can then be selected in the order of their overall operating characteristic values.

[0053] In the flowchart according to Figure 4the second method step V2 is shown in more detail in an embodiment of the method V. In a first sub-step S1, the at least one flow generator unit 11 can first be selected and then the respective individual target operating state BSi can be determined for each selected flow generator unit 11 (second sub-step S2).

[0054] Subsequently, in a third sub-step S3, it is checked whether each individual target operating state BSi represents a permissible stationary operating state of the respective flow generator unit 11 or is excluded as a stationary operating state by an operating limitation LIM.

[0055] If it is found in the third sub-step S3 that all individual target operating states BSi are permissible as stationary operating states (branch OK from the third sub-step S3), the second method step V2 is terminated and the method V can then be continued in the third method step V3, as described in Figure 3 is illustrated. Otherwise (branch NOK from the third sub-step S3), in a fourth sub-step S4 either the selection of the flow generator units 11 from the flow generator group 12 is changed and / or the individual target operating state BSi or the individual target operating states BSi of the selected flow generator units 11 are adapted, so that all individual target operating states BSi are not excluded as a stationary operating state by an operating limitation LIM.

[0056] The selection of the flow generator units 11 and / or the changing of the individual target operating states BSi can be carried out iteratively in a loop consisting of the third sub-step S3 and the fourth sub-step S4, as indicated by the dashed arrow in Figure 4 is shown.

[0057] It may be advantageous to carry out the adjustment in the fourth sub-step S4 once, so that the method can then be repeated in the third method step V3 according to Figure 3 can be continued.

[0058] In one embodiment, a local control unit 19 can adapt the individual target operating state BSi determined for it in order to avoid steady-state operation, which is excluded by the individual operating limitation LIM. For example, the power (in particular, speed n) can be increased or decreased for this purpose, so that the respective flow generator unit 11 provides a higher or lower power. This power difference is transmitted by the local control unit 19 to the other selected flow generator units 11, which then compensate for the power difference in such a way that an individual target operating state BSi is also obtained for all other selected flow generator units 11, which is not excluded by the respective individual operating limitation LIM.For example, one or more of the other selected flow generator units 11 may increase or decrease their respective power so that the overall predetermined control or regulation objective is achieved.

[0059] In order to avoid stationary operation in an unsuitable operating state, it is intended to repeatedly determine the operating limitation LIM for each flow generator unit 11. For this purpose, the flow generator unit 11 can be operated in at least one defined operating state during a test CM or determination of the individual operating limitation, as shown schematically in Figure 5 is illustrated using the example of a rotational speed n of the electric motor 30. During the testing or determination of the individual operating limitation of the flow generator unit 11, a monitoring parameter MP is monitored, based on which an undesirable stationary operating state can be defined.

[0060] For example, a vibration parameter OS is used as the monitoring parameter MP. The vibration parameter OS can describe a vibration of the flow generator unit 11 or the fan 14 and can be measured, for example, using an acceleration sensor or microphone or another suitable vibration sensor. In particular, such a vibration sensor can be a local sensor 26 of the flow generator unit 11 or the fan 14. It can be arranged on a component of the fan 14 or a device fluidly coupled to the fan 14. Using the vibration parameter OS as the monitoring parameter MP, for example, resonant vibrations at a certain speed n of the electric motor 30 or the fan rotor 31 can be detected and corresponding speed ranges can be excluded by defining an operating limitation LIM, as will be shown below by way of example using the Figures 5 and 6 is explained.

[0061] For example, the speed n of the electric motor 30 or the fan rotor 31 can be varied during the test CM or determination of the individual operating limitation within a specified test speed range from a minimum speed n min to a maximum speed n max. Figure 5 In the illustrated embodiment, the speed n is increased continuously and, for example, linearly. The speed n could also be changed in steps or without jumps along a non-linear curve within the test speed range. The test speed range from the minimum speed n min to the maximum speed n max can either include at least the speeds in which a resonant oscillation is expected or the entire nominal speed range of the flow generator unit 11 or the fan 14.

[0062] While the speed n is varied during the CM test, the monitoring parameter MP and, for example, the vibration parameter OS are monitored and checked to determine whether the monitoring parameter MP lies within a specified permissible range. For example, a maximum permissible value for the vibration amplitude can be defined for the vibration parameter OS.

[0063] For example, the explanation in Figure 6At a first time t1, the exceeding of the permissible amplitude A is represented by the vibration parameter OS. At this first time t1, the speed n of the electric motor 30 has a first speed value n 1 . A stationary operation with a speed n corresponding to the first speed value n 1 is therefore not suitable and is avoided by a corresponding operating limitation LIM. For this purpose, a speed range which is not suitable for stationary operation and which has the first speed value n 1 can be defined as the operating limitation LIM. In this way, vibrations with amplitudes which exceed the amplitude limit value A can be avoided, as shown schematically in the Figures 5 and 6 is illustrated.

[0064] If an initially determined individual operating state BSi lies within the speed range excluded by the operating limitation LIM around the first speed value n 1 , the control device 17, in particular the relevant local control unit 19, can adapt the initially determined individual operating state BSi and set the speed to the lower limit or the upper limit of the speed range excluded by the operating limitation LIM in order to deviate as little as possible from the initially determined individual operating state BSi. As explained, the resulting power difference can be compensated by one or more other selected flow generator units 11.

[0065] Alternatively or in addition to the vibration parameter OS, another monitoring parameter MP can be monitored, such as an operating temperature of the electric motor 30 and / or the local control unit 19. The operating limitation LIM can also exclude operating states and in particular speed ranges in which the flow generator unit 11 does not achieve a minimum efficiency.

[0066] The invention relates to a method for operating a flow generation system 10 and to a flow generation system 10 configured to carry out the method. The flow generation system 10 has at least one flow generator group 12, each comprising a plurality of flow generator units 11. The flow generator units 11 can be, for example, fans 14. The flow generator units 11 of a common flow generator group 12 are fluidically connected to a common flow space 13. The flow generator units 11 of a common flow generator group 12 are controlled in a coordinated manner by means of a control device 17, so that a control or regulation target predetermined by at least one target parameter PG is achieved.For this purpose, one or more flow generator units 11 are selected from the flow generator group 12, and an individual target operating state BSi is determined for each of the selected flow generator units 11. The respectively determined target operating state BSi is checked against an individual operating limitation LIM to determine whether it is permitted for stationary operation. If this is not the case for one or more of the determined target operating states BSi, two or more target operating states BSi are changed until all target operating states BSi of the selected flow generator units 11 are permitted, i.e., are not excluded from stationary operation by a respective operating limitation LIM. In this case, it is additionally or alternatively possible to change the selection of the flow generator units 11 from the common flow generator group 12. List of reference symbols:

[0067] 10Flow generation system 11Flow generator unit 12Flow generator group 13Flow chamber 14Fan 17Control device 18Higher-level control 19Local control unit 20Communication interface 21Communication network 25Sensor 26Local sensor 27System sensor 30Electric motor 31Fan rotor 32Motor control 33Data storage AAmplitude limit value BSiTarget operating state of a flow generator unit (i=1, 2, 3, ..., n) CMTest FIndividual fluid flow GFTotal fluid flow LAir flow LIMOperating limitation MPMonitoring parameter nSpeed ​​n 1 First speed value n max Maximum speed n min Minimum speed OSVibration parameter PGTarget parameter S1First sub-step S2Second sub-step S3Third sub-step S4Fourth sub-step tTime t1First point in time VProcedure V1First process step V2Second process step V3Third process step

Claims

1. Method (V) for operating a flow generation system (10) comprising a control device (17) and a flow generator group (12) controllable by means of the control device (17) and having a plurality of flow generator units (11), each of which is configured to generate an individual fluid flow (F), wherein the flow generator units (11) are fluidically connected to a common flow space (13), wherein the method comprises: - specifying at least one target parameter (PG) to be set for the atmosphere in the flow space (13), - selecting at least one flow generator unit (11) from a flow generator group (12) and determining an individual target operating state (BSi) for each selected flow generator unit (11), taking into account repeatedly determined individual operating limitations (LIM), in order to set the at least one target parameter (PG).

2. The method according to claim 1, wherein the individual operating limitations (LIM) of the flow generator units (11) are repeatedly determined in a time-controlled and / or event-controlled manner.

3. Method according to claim 1 or 2, wherein each flow generator unit (11) is operated in several different operating states to determine its individual operating limitation (LIM).

4. The method according to claim 3, wherein, in order to determine the individual operating limitation (LIM) of a flow generator unit (11), operating states with different mechanical and / or electrical powers of the flow generator unit (11) are set.

5. The method according to claim 3 or 4, wherein, in order to determine the individual operating limitation (LIM) of a flow generator unit (11), a monitoring parameter (MP) dependent on the operation of the flow generator unit (11) is determined and it is checked whether the monitoring parameter (MP) lies within a predetermined permissible range.

6. The method according to claim 5, wherein the monitoring parameter (MP) is a vibration parameter (OS).

7. Method according to one of the preceding claims, wherein a downtime of a non-selected flow generator unit (11) is detected and the flow generator unit (11) is at least temporarily put into operation if the downtime exceeds a maximum duration.

8. Method according to one of the preceding claims, wherein an overall operating characteristic value of each flow generator unit (11) is determined and, when selecting the flow generator units (11) from the flow generator group (12), the flow generator units (11) with the overall operating characteristic value which characterizes a lower load on the flow generator unit (11) are prioritized.

9. Method according to one of the preceding claims, wherein each individual operating limitation (LIM) defines at least one operating state of the respective flow generator unit (11) which is unsuitable for stationary operation of the flow generator unit (11).

10. Method according to one of the preceding claims, wherein the at least one target parameter (PG) is one or more of the following parameters in any combination: a pressure of the atmosphere in the flow space (13), a temperature of the atmosphere in the flow space (13), a humidity of the atmosphere in the flow space (13), a flow velocity of a total fluid flow (GF) in the flow space (13) and / or a volume flow of a total fluid flow (GF) in the flow space (13).

11. Flow generation system (10) comprising a control device (17) and a flow generator group (12) controllable by means of the control device (17) with a plurality of flow generator units (11), each of which is configured to generate an individual fluid flow (F), wherein the flow generator units (11) are fluidically connected to a common flow space (13), wherein the control device (17) is configured to carry out the following method: - specifying at least one target parameter (PG) to be set for the flow space (13), - selecting at least one flow generator unit (11) from a flow generator group (12) and determining an individual target operating state (BSi) for each selected flow generator unit (11), taking into account repeatedly determined individual operating limitations (LIM), in order to set the at least one target parameter (PG).

12. Flow generation system according to claim 11, wherein each flow generator unit (11) further comprises a controllable electric motor (30) and a rotor (31) drivingly connected to the electric motor (30).

13. Flow generation system according to claim 11 or 12, wherein the control device (17) comprises a plurality of communicatively connected local control units (19) and each flow generator unit (11) has an individual local control unit (19).

14. Flow generation system according to claim 12 and claim 13, wherein each local control unit (19) is a motor controller (32) of the electric motor (30).

15. Flow generation system according to one of claims 11 to 14, wherein the control device (17) has a higher-level controller (18) which is communicatively connected to the flow generator units (11).

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