Control method for controlling a pump assembly

Abstract

The present invention is directed to a control method for controlling a pump assembly (105a) being configured to be used as one of a plurality of pump assemblies (105a-c) for transporting thermal energy from a common thermal energy source (103) into a plurality of building zones, wherein each of the plurality of pump assemblies (105a-c) is associated with one of the building zones and configured to drive a zone-specific thermal energy flow from the common thermal energy source (103) into the associated building zone, wherein the method comprises the following steps carried out by said pump assembly (105a): - providing a receiving opportunity to receive, via a wireless communication network (109), a zone temperature information from an associated zone temperature sensor (107a) being arranged at the building zone associated with said pump assembly (105a); - determining or processing an associated zone temperature deviation (ΔT) based on the received zone temperature information; - sending, via the wireless communication network (109), the associated zone temperature deviation (ΔT) and / or a current operating variable (ω) of said pump assembly ( 105a) to the other pump assemblies (105j); - determining an external failure status of each of the other pump assemblies (105j) based on a received zone temperature deviation (ΔTj) associated with said other pump assembly (105j) and / or a received current operating variable (ωj) of said other pump assembly (105j), and / or determining an internal failure status; and - controlling a variable pump speed (ω) of said pump assembly (105a) depending on the zone temperature deviation associated with said pump assembly (105a) and depending on the external failure status of the other pump assemblies (105j) and / or the internal failure status.

Description

[0001] Applicant: GRUNDFOS HOLDING A / S

[0002] Title: Control method for controlling a pump assembly

[0003] Our Ref.: GP 3825 WO

[0004] Description

[0005] TECHNICAL FIELD

[0006]

[0001] The present invention is directed to a control method for controlling a pump assembly being configured to be used as one of a plurality of pump assemblies for transporting thermal energy from a common

[0007] 5 thermal energy source into a plurality of building zones, wherein each of the plurality of pump assemblies is associated with one of the building zones and configured to drive a zone-specific thermal energy flow from the common thermal energy source into the associated building zone.

[0008] BACKGROUND

[0009] 10

[0010]

[0002] Zone pumping systems are commonly used, in particular in the United States and elsewhere, as part of a hydronic system for heating or cooling a building that comprises a plurality of building zones. One of the building zones may be a room or building section that is supposed to have a certain target temperature. The same or a different target temperature may be set for another one of the building zones.

[0011]

[0003] In contrast to valve-controlled hydronic systems, in which each valve opens and closes depending on an associated target temperature to control a thermal energy flow through an associated branch of

[0012] 20 the hydronic system, zone pumping systems control a zone-specific thermal energy flow by switching on / off a plurality of pump assemblies, wherein each of the plurality of pump assemblies is associated with one of the building zones. So, each building zone has its own associated

[0013] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 pump assembly to deliver the thermal energy flow that is needed to achieve a certain target zone temperature.

[0014]

[0004] For example, WO 2024 / 033484 Al describes a zone pumping system with a central control unit to switch on / off zone pumps to a achieve

[0015] 5 a certain target zone temperature. US 2017 / 021921 Al describes a central control unit for a hydronic heating system, wherein the heat response is varied based on an actual thermal energy demand of a building zone.

[0016]

[0005] The known prior art systems come with certain disadvantages. Firstly, the installation cost and effort is quite high to connect the central

[0017] 10 control with all pumps and all temperature sensors. Secondly, both the user comfort for experiencing stable target zone temperatures and the system efficiency of known prior art systems can be improved.

[0018]

[0006] It is therefore an object of the present invention to provide a control method for controlling a pump assembly that reduces the installation cost and effort, and that improves the user comfort and system efficiency.

[0019] SUMMARY

[0020]

[0007] The control method according to independent claim 1 provides a solution to achieve this object.

[0021] 20

[0008] According to a first aspect of the present invention, a control method is provided for controlling a pump assembly being configured to be used as one of a plurality of pump assemblies for transporting thermal energy from a common thermal energy source into a plurality of building zones, wherein each of the plurality of pump assemblies is associated

[0022] 25 with one of the building zones and configured to drive a zone-specific thermal energy flow from the common thermal energy source into the associated building zone, wherein the method comprises the following steps carried out by said pump assembly:

[0023] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 providing a receiving opportunity to receive, via a wireless communication network, a zone temperature information from an associated zone temperature sensor being arranged at the building zone associated with said pump assembly;

[0024] 5 determining or processing an associated zone temperature deviation based on the received zone temperature information; sending, via the wireless communication network, the associated zone temperature deviation and / or a current operating variable of said pump assembly to the other pump assemblies; determining an external failure status of each of the other pump assemblies based on a received zone temperature deviation associated with said other pump assembly and / or a received current operating variable of said other pump assembly, and / or determining an internal failure status; and

[0025] 15 controlling a variable pump speed of said pump assembly depending on the zone temperature deviation associated with said pump assembly and depending on the external failure status of the other pump assemblies and / or on the internal failure status.

[0026]

[0009] The inventive control method does not need a central control unit,

[0027] 20 which reduces heavily the installation burden. The inventive control method is de-centralised by implementing the control algorithms on preferably all of the plurality of pump assemblies. Most preferably, all of the plurality of pump assemblies are programmed and configured to execute the same inventive control method. Preferably, “the other pump assemblies” shall include all of those other pump assemblies of the plurality of pump assemblies that are also configured to carry out the inventive control method.

[0028]

[0010] An internal failure status may, for example, be a communication status indicating whether the communication connection with the asso¬

[0029] 30 ciated temperature sensor and / or with the other pump assemblies is properly working or not. An external failure status may, for example, be

[0030] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 a saturation status indicating whether at least one of the other pump assemblies is suffering from a saturation situation or not.

[0031]

[0011] Preferably, each of the pump assemblies is in communication connection, via the wireless communication network, with an associated

[0032] 5 temperature sensor that is arranged at the building zone which is associated with said pump assembly. So, for each building zone, the associated pump assembly is able to directly or indirectly receive zone temperature information from the associated temperature sensor. The zone temperature information may be a measured zone temperature or a

[0033] 10 zone temperature deviation of a measured zone temperature from a reference zone temperature. If the received zone temperature information is already a zone temperature deviation, the pump assembly may only process said received zone temperature deviation. If the received zone temperature information is a measured zone temperature, the pump assembly may determine a zone temperature deviation of the received measured zone temperature from a reference zone temperature. The reference zone temperature may be set by a user application being executed on a remote-control device. Such a zone-specific user setting may be communicated to the associated temperature sensor and / or to

[0034] 20 the associated pump assembly for determining the zone temperature deviation by the associated temperature sensor or by the associated pump assembly.

[0035]

[0012] So, optionally, the zone temperature information may be a measured zone temperature or already the zone temperature deviation, wherein the zone temperature deviation is a difference between the measured zone temperature and a reference zone temperature, wherein the reference zone temperature is based on a user-defined target zone temperature minus a saturation offset which may depend on the external failure status of the other pump assemblies.

[0036] 30

[0013] Optionally, the current operating variable may be an absolute or relative value being indicative of a current pump speed and / or current

[0037] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 pump power consumption. The pump assemblies share information about theircurrent operating variable and / ortheirzone temperature deviation with the other pump assemblies. It may depend on the external failure status and the internal failure status what the minimum of infor¬

[0038] 5 mation is that needs to be shared among the pump assemblies.

[0039]

[0014] Optionally, the internal failure status and / or the external failure status of the other pump assemblies may be a saturation status or a communication status, or a combination of the saturation status and the communication status. If the external failure status comprises a saturation

[0040] 10 status, information about both the current operating variable and the zone temperature deviation may be shared with the other pump assemblies. The saturation status may indicate whether there is a saturation for the associated building zone. A saturation means here that a current operating variable reaches a limit, e.g. a maximum pump speed or power is reached, and nevertheless the zone temperature deviation cannot be reduced. In other words, the building zone does not receive the required thermal energy flow that is necessary to achieve a target temperature in said building zone despite the associated pump assembly running at maximum speed. The reason for such a situation is that other building

[0041] 20 zones may consume a too large fraction of the total thermal energy provided by the common thermal energy source, so that the saturated building zone is “starving”.

[0042]

[0015] Optionally, the variable pump speed of said pump assembly may be reduced if the external failure status of one or more of the other pump assemblies indicates a saturation. So, the pump assembly helps the one or more saturated other pump assemblies by reducing its consumption share of the total thermal energy provided by the common thermal energy source. This may be done until the external failure status of all pump assemblies indicates a non-saturation. Then, the controlling of the varia¬

[0043] 30 ble pump speed of each pump assembly may return to a normal operating mode in which the associated zone temperature deviation is used

[0044] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 in a closed-loop control as a feedback error to be reduced by adapting the variable pump speed.

[0045]

[0016] Optionally, the variable pump speed may be reduced by an absolute or relative reduction amount that depends on the zone tempera¬

[0046] 5 ture deviation(s) associated with the one or more other pump assemblies with an external failure status that indicates saturation. This is useful to achieve a non-saturation status quicker.

[0047]

[0017] If the internal failure status comprises only a communication status, it may be sufficient to share only information about the current oper¬

[0048] 10 ating variable with the other pump assemblies. For example, in case of a lost communication connection with the associated temperature sensor, a current pump speed of another pump assembly or an average of current pump speeds of other pump assemblies may be used for the variable speed control of the pump assembly. It is thus a best guess to adapt the variable pump speed pump assembly based on how the other pump assemblies adapt their variable pump speed if zone temperature information about the associated building zone is missing. For example, if the other pump assemblies reduce their pump speed on average by 10%, the pump assembly having lost its communication connection with the

[0049] 20 associated temperature sensor may also reduce its pump speed by 10%. Alternatively, a pre-determined or variable factor C may be applied, e.g. Aro / ro = wherein A^ / ^ is the relative change of an average pump speed of the other pump assemblies j.

[0050]

[0018] Optionally, the variable pump speed of said pump assembly may be controlled based on a latest pump speed before the communication failed if the internal failure status indicates a failing communication with all of the other pump assemblies. This is a fallback solution in case all communication connection is lost, not only to the associated zone temperature sensor, but also to all of the other pump assemblies. It is thus a

[0051] 30 best guess in such a situation to continue operating the pump assembly as before. The rationale is here that a continuation with the same pump

[0052] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 speed is generally more likely to be needed than a change of pump speed.

[0053]

[0019] Optionally, the method may further comprise configuring each of the pump assemblies, via the wireless communication network, by a user

[0054] 5 application being executed on a remote-control device. The remotecontrol device may be smartphone, tablet, PC or other portable or stationary computer device that a user may use to execute a user application program. Thereby, the user may set target zone temperatures for any of the building zones as a configuration parameter of the pump assem¬

[0055] 10 blies being associated with the respective building zones.

[0056]

[0020] Optionally, a Matter® Smart Home Communication Standard Version 1 .3 or later may be used as a communication protocol for communicating via the communication via the wireless communication network, e.g. Wi-Fi, Thread, 6L0WPAN, or another wireless communication network standard. This is particularly useful to establish a working communication with non-proprietary zone temperature sensors and / or user application programs. The pump manufacturer may not know which type or make of temperature sensors of any other manufacturer may be used to implement the heating system. The Mattei® Smart Home Communication

[0057] 20 Standard Version 1 .3 or later helps to achieve a working communication connection among a large variety of smart home devices independent of their type and make. Also, the user application program running on a remote-control user device may be part of a standardised program for setting one or more pump configuration parameters, e.g. a target zone temperature. A proprietary user application program may then not be needed anymore to configure the pump assemblies. The pump assembly may send, via the wireless communication network, the associated zone temperature deviation and / or its current operating variable, e.g. its pump speed, to the other pump assemblies by way of a broadcasting

[0058] 30 message, wherein the other pump assemblies are subscribed to listen to such a broadcasting message. Alternatively, the sending may be directly addressed to the other pump assemblies.

[0059] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025

[0021] Optionally, the step of controlling the variable pump speed may include setting the variable pump speed to zero if the associated temperature value indicates a zone overheat in excess of a pre-determined relative or absolute overheat tolerance in the associated building zone.

[0060] 5 Such a pre-determined relative or absolute overheat tolerance in the associated building zone may be another pump configuration parameter that may be settable by a user through the user application program running on the remote-control user device. This means that a pump assembly is switched off to protect the associated zone against over-heat¬

[0061] 10 ing.

[0062]

[0022] Optionally, the control method may further comprise sending a thermal energy demand signal to the common thermal energy source. Such a thermal energy demand signal may trigger the common thermal energy source to switch on / off depending on whether at least one of the plurality of pump assemblies is running with sufficient speed, so that there either is a sufficient thermal energy demand for the common thermal energy source to run or not. For example, the pump assembly may be chosen to be one of the plurality of pump assemblies to communicate with the common thermal energy source in the name of all of the plural¬

[0063] 20 ity of pump assemblies to tell whether thermal energy is needed from the common thermal energy source. If none of the plurality of pump assemblies is running, or if one or more run so slowly that a minimum thermal energy demand for the common thermal energy source to switch on is not reached, the common thermal energy source may be switched off or remain switched off. A “smart” common thermal energy source may not need the thermal energy demand signal if it has other means to decide when to switch on / off. However, if the common thermal energy source is not so smart, it is useful to provide the thermal energy demand signal by at least one of the plurality of pump assemblies.

[0064] 30

[0023] Optionally, the steps of the above-described method may be carried out by each of the plurality of pump assemblies. As already men-

[0065] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 tioned above, this is useful for all building zones to benefit from the inventive control method. The inventive control method is, however, still beneficial if one or some of the building zones are not temperature-controlled according to the inventive control method.

[0066] 5

[0024] According to another aspect of the present invention, a computer program is provided comprising instructions which, when the program is executed by a pump assembly, cause the pump assembly to carry out the steps of the above-described method. The inventive control method may be implemented by a software upgrade including the

[0067] 10 computer program to existing pump assemblies that may or may not already be installed. The computer program may be downloaded, e.g. upon a user request via the user application program running on the re- mote-control user device, by the pump assembly. There may no hardware change of the pump assembly be necessary to implement the inventive control method.

[0068]

[0025] So, according to another aspect of the present invention, a user application program is provided comprising instructions which, when the program is executed by a remote-control device, configures a pump assembly via the wireless communication network to carry out the steps of

[0069] 20 the above-described method. Such a user application program may be conveniently used by a user to monitor, configure and / or upgrade the pump assembly.

[0070]

[0026] According to another aspect of the present invention, a remotecontrol device is provided being configured to execute such a user application program. The most preferred remote-control device may be a smartphone with the user application program in form of an app.

[0071]

[0027] According to another aspect of the present invention, a pump assembly is provided being configured to be used as one of a plurality of pump assemblies for transporting thermal energy from a common

[0072] 30 thermal energy source into a plurality of building zones, wherein the

[0073] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 pump assembly is configured to be associated with one of the building zones and configured to drive a zone-specific thermal energy flow from the common thermal energy source into the associated building zone, wherein the pump assembly is configured to carry out the steps of the

[0074] 5 above-described method. The inventive pump assembly may thus be readily equipped, configured and programmed to preform the inventive control method as one of a plurality of pump assemblies that are used for zone pumping.

[0075]

[0028] The method disclosed herein may be implemented in form of com¬

[0076] 10 piled or uncompiled software code that is stored on a computer readable medium with instructions for executing the method by one, more or all of the plurality of pump assemblies.

[0077]

[0029] The present invention may be implemented in form of a system, a method, and / or a computer program product at any possible technical

[0078] 15 detail level of integration. The computer program product may include a computer readable storage medium (or media) having computer readable program instructions thereon for causing a processor of one, more or all of the plurality of pump assemblies to carry out aspects of the present invention.

[0079] 20

[0030] The computer readable storage medium can be a tangible device that can retain and store instructions for use by an instruction execution device. The computer readable storage medium may be, for example, but is not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. A non-exhaustive list of more specific examples of the computer readable storage medium includes the following: a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory),

[0080] 30 a static random access memory (SRAM), a portable compact disc readonly memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a

[0081] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 floppy disk, a mechanically encoded device such as punch-cards or raised structures in a groove having instructions recorded thereon, and any suitable combination of the foregoing. A computer readable storage medium, as used herein, is not to be construed as being transitory signals per

[0082] 5 se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through a waveguide or other transmission media (e.g., light pulses passing through a fibre-optic cable), or electrical signals transmitted through a wire.

[0083]

[0031] Computer readable program instructions described herein can be downloaded to respective pump assemblies from a computer readable storage medium or to an external computer or external storage device via a network, for example, the Internet, a local area network, a wide area network and / or a wireless network. The network may comprise copper transmission cables, optical transmission fibres, wireless transmis¬

[0084] 15 sion, routers, firewalls, switches, gateway computers and / or edge servers. A network adapter card or network interface in each pump assemblies may receive computer readable program instructions from the network and may forward the computer readable program instructions for storage in a computer readable storage medium within the respective

[0085] 20 pump assembly.

[0086] SUMMARY OF THE DRAWINGS

[0087]

[0032] Embodiments of the present invention will now be described by way of example with reference to the following figures of which:

[0088] Fig. 1 shows schematically a prior art zone pumping system with a central controller and a temperature diagram for the zones over daytime;

[0089] Fig. 2 shows schematically an example of an inventive zone pumping system without a central controller and a tem¬

[0090] 30 perature diagram for the zones over daytime;

[0091] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 Fig. 3a-f shows histograms of measurement events in bins of zone temperature in each of three zones and in bins of return temperature in each of the three zones for the inventive

[0092] 5 control method in comparison with the prior art;

[0093] Fig. 4 shows a flow diagram of an example of an inventive control method;

[0094] Fig. 5 shows a flow diagram of a saturation mode routine of an example of an inventive control method;

[0095] Fig. 6 shows a flow diagram of certain steps of an example of an inventive control method; and

[0096] 15

[0097] Fig. 6 shows a flow diagram of a safe mode routine of an example of an inventive control method.

[0098] DETAILED DESCRIPTION

[0099] 20

[0033] Fig. 1 shows schematically a zone pumping system 1 known in the prior art, e.g. WO 2024 / 033484 Al . The known zone pumping system 1 is here a hydronic system for heating a building comprising three building zones, namely zone 1 , zone 2 and zone 3. The zone pumping system 1 comprises a common heat source 3, three pump assemblies 5a-c and three temperature sensors 7a-c. Each of the temperature sensors 7a-c is arranged in one of the building zones zone 1 , zone 2 and zone 3, respectively. A first pump assembly 5a of the three pump assemblies 5a-c is arranged to drive a heat flow into building zone 1 , where a first temperature sensor 7a of the three temperature sensors 7a-c measures the zone

[0100] 30 temperature of building zone 1 . Analogously, a second pump assembly 5b of the three pump assemblies 5a-c is arranged to drive a heat flow through building zone 2, where a second temperature sensor 7b of the

[0101] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 three temperature sensors 7a-c is installed to measure the zone temperature of building zone 2. Analogously, a third pump assembly 5c of the three pump assemblies 5a-c is arranged to drive a heat flow through building zone 3, where a third temperature sensor 7c of the three tem¬

[0102] 5 perature sensors 7a-c is installed to measure the zone temperature of building zone 3. All pump assemblies 5a-c and temperature sensors 7a-c are connected by wiring with a central controller 1 1 that is configured to switch on / off the pump assemblies a-c depending on the zone temperatures measured by the temperature sensors 7a-c. The heat source 3 is

[0103] 10 also connected by wire with the central controller 1 1 , so that the central controller 1 1 is also able to control operation of the heat source 3. The central controller 1 1 is connected to a powerline providing a supply voltage of 1 10 V (typically in the US) or 220 / 230 V (typically in Europe). Fig. 1 further shows a diagram of measured temperatures of the three temperature sensors 7a-c of the known zone pumping system 1 over daytime. As can be seen, switching on / off the pump assemblies 5a-c by the central controller 1 1 leads to significant temperature fluctuations in the range of ±1 °C or more. There is thus a potential for improvement regarding the user comfort that would benefit from less temperature fluctuations in the

[0104] 20 building zones 1 , 2 and 3.

[0105]

[0034] Fig. 2 shows an inventive zone pumping system 100 in form of a hydronic system being installed for heating building zones 1 , 2 and 3. The inventive zone pumping system 100 comprises a common thermal energy source 103, a plurality of pump assemblies 105a-c and a plurality of temperature sensors 107a-c. There is no central controller and no wiring for communication among the devices of the zone pumping system 100. Instead, the controlling of the inventive zone pumping system 100 is decentralized, wherein each of the pump assemblies 105a-c is configured to execute an inventive control method described below. The inventive

[0106] 30 control method uses a Matter® Smart Home Communication Standard Version 1 .3 or later as a communication protocol for communicating via the wireless communication network 109 that allows wireless communi-

[0107] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 cation among the pump assemblies 105a-c as well as between the temperature sensors 107a-c and the pump assemblies 105a-c. The inventive zone pumping system 100 further comprises a remote-control device 1 1 1 in form of a smartphone with a user application program in form of an

[0108] 5 app. The remote-control device 1 1 1 can be conveniently used by a user to monitor, upgrade, configure and / or program the pump assemblies 105a-c via the wireless communication network 109. Also, the thermal energy source 103 is here connected to the other devices 105a-c, 107a- c, 1 1 1 via the wireless communication network 109.

[0109] 10

[0035] Fig. 2 also shows a diagram of zone temperatures measured by the temperature sensors 107a-c over daytime. As can be seen, the temperature fluctuations are heavily reduced compared to the prior art zone pumping system 1 as shown in Fig. 1 . Thus, the user comfort is significantly increased in all three building zones 1 , 2 and 3.

[0110]

[0036] Figs. 3a-f also show the advantageous effect of the inventive zone pumping system 100 compared to the prior art zone pumping system 1 of Fig. 1 . Fig. 3a shows a normalized histogram of measurement events in bins of measured temperature of the first temperature sensor 107a compared to the prior art temperature sensor 7a of Fig. 1 . Figs. 3b, c show the

[0111] 20 same histogram for the second temperature sensors 107b, 7b in building zone 2 and the third temperature sensors 107c, 7c in building zone 3, respectively. As can be seen, the histograms of the inventive zone pumping system 100 are much narrower peaked around a target zone temperature of 22°C than the histograms of the prior art zone pumping system 1 of Fig. 1 .

[0112]

[0037] Figs. 3d-f show normalized histograms of measurement events in bins of return temperature for the respective building zones 1 , 2 and 3. It should be noted that temperature sensors for measuring the return temperature of the individual return lines from the building zones 1 , 2 and 3

[0113] 30 are not shown in Figs. 1 and 2, because return temperature sensors are

[0114] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 not needed for the control method. However, measuring the return temperatures is useful to show the efficiency of the inventive zone pumping system 100 compared to the prior art zone pumping system 1. The efficiency of the common thermal energy source 103, 3, e.g. a condensing

[0115] 5 boiler, depends on the return temperature. The lower the return temperature is, the more efficiently the thermal energy source 103, 3 is able to recover latent heat of vaporization. As can be seen in Figs. 3d-f, the return temperature of the inventive zone pumping system 100 is significantly lower than the return temperature of the prior art zone pumping

[0116] 10 system 1 for all three building zones 1 , 2 and 3. This means that the inventive zone pumping system 100 is significantly more efficient than the prior art zone pumping system 1 as shown in Fig. 1 .

[0117]

[0038] Fig. 4 shows schematically a flow chart of method steps of an embodiment of the inventive control method disclosed herein. In the following, the control method is described, by way of example, taking the perspective of the first pump assembly 105a that is associated with building zone 1 , where the associated temperature sensor 107a measured the zone temperature. A skilled reader will understand that the control method may be applied by any of the other pump assemblies 105], j e

[0118] 20 [b, c , in the same way.

[0119]

[0039] The control method starts with an initializing step 401 and continues with step 403, in which a thermal energy demand signal is disabled and an uncertainty counter is increased. The disabled thermal energy demand signal may be used by the common thermal energy source 103 to stop or not to start providing thermal energy. In the following step 405, it is checked whether other pump assemblies 105j, j e [b, c , are running. If so, the control method continues with step 407, in which an average of pump speeds of all other running pump assemblies 105], j e [b, c , is calculated. Each of the pump assemblies 105a, 105b, 105c of the inventive

[0120] 30 pump zone system 100 shares information about their current pump speed co with the other pump assemblies 105], / e [b, c , via the wireless

[0121] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 communication network 109. In the following step 409, the thermal energy demand signal is enabled if at least one of the other pump assemblies 105j, j e [b, c , is running at a sufficient speed, so that there is a sufficient thermal energy demand for the common thermal energy source

[0122] 5 103 to provide thermal energy. If none of the plurality of pump assemblies is running or if the running ones run so slowly that the thermal energy demand is too small for the common thermal energy source 103 to be worth providing thermal energy, the thermal energy demand signal may be disabled or kept disabled. The enabled thermal energy demand signal

[0123] 10 may be used by the common thermal energy source 103 to start or not to stop providing thermal energy. In the following step 41 1 , the pump assembly 105a checks whether it has a communication connection with the temperature sensor 107a that is arranged in the associated building zone 1. If step 405 results in having no other running pump assemblies

[0124] 15 105j, j e [b, c , available, the control method jumps to step 41 1. If the pump assembly 105a does not have a working communication connection with its associated temperature sensor 107a, a backup operation flag is set to TRUE in step 413.

[0125]

[0040] Once the backup operation flag is set to TRUE in step 413, the

[0126] 20 pump assembly 105a is operated in a backup mode. In the backup mode, it is checked in following step 415 if there is a working communication connection with any of the other pump assemblies 105], j e [b, c . If this is not the case, the pump assembly 105a updates its own pump speed a> to a latest trusted pump speed in step 417. If, however, there is

[0127] 25 a working communication connection with at least one of the other pump assemblies 105], j e [b, c , it is checked in step 419 if the trust has been lost to the latest pump speed, for example because a maximum time has lapsed since the latest trusted speed was updated. If the latest pump speed can still be trusted in step 419, the control method continues

[0128] 30 with step 417, wherein the latest trusted speed is used to update the pump speed a>. However, if the trust in the latest pump speed has been lost, the pump speed a> is updated relative to the latest trusted speed and a pump speed of one or more of the other pump assemblies 105],

[0129] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 j e [b, c , in step 421 . If there is a working communication connection with more than one pump in step 415, an average of pump speeds of said other pump assemblies 105j, j e [b, c , may be used to update the pump speed in step 421. Both steps 417 and 421 are followed by step 423, in

[0130] 5 which it is checked whether the pump speed a> is above a minimum speed limit. If this is not the case, the pump speed is set to zero in step 425. The pump assembly 105a is then run in step 427 at the set pump speed co, i.e. switched off if the pump speed is set to zero. If the pump speed is above the minimum speed limit in step 423, the pump speed is

[0131] 10 set in step 429, in which the thermal energy demand signal is also enabled. The pump assembly 105a is then run with the set pump speed in step 427. The control method is then recursively continued with step 403.

[0132]

[0041] If step 41 1 yields that the pump assembly 105a has a working communication connection with the associated temperature sensor 107a, the pump uncertainty counter is reset in step 431 , i.e. the pump assembly’s 105a internal failure status indicates a working communication connection. A saturation mode routine is then executed in following step 433. The saturation mode routine is explained in more detail in Fig. 5. The saturation mode routine results in a dynamically determined refence zone

[0133] 20 temperature Tret. In the following step 435, a zone temperature deviation AT between the dynamically determined reference zone temperature Tret and a zone temperature Tmeasured measured by the associated temperature sensor 107a is calculated. Once the zone temperature deviation AT is determined in step 435, a PID controller routine is executed in step 437 for determining the pump speed co to be set. The PID controller routine is explained in more detail in Fig. 6. It follows in step 439 a safe mode routine to check for a zone overheating. The safe mode routine in step 439 is explained in more detail in Fig. 7.

[0134]

[0042] The backup operation flag is set in step 441 to FALSE. In following

[0135] 30 step 443, the pump speed co is validated and updated as being the latest trusted pump speed. The control method then continues with steps 423, 425, 427 or 423, 429, 427.

[0136] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025

[0043] The embodiment of the control method shown in Fig. 4 implies that the pump assembly 105a provides a receiving opportunity to receive, via the wireless communication network 109, a zone temperature information from the associated zone temperature sensor 107a that is ar¬

[0137] 5 ranged at the building zone 1 being associated with the pump assembly 105a. The zone temperature information is here preferably a measured zone temperature Tmeasured determined by the associated zone temperature sensor 107a. In step 435, an associated zone temperature deviation AT is determined based on the received zone temperature information. The pump assembly 105a shares its associated zone temperature deviation AT and its current pump speed a> with all of the other pump assemblies 105], j e [b, c , via the wireless communication network 109. The pump assembly 105a determines its internal failure status in step 41 1 by checking whether it has a working communication connection with its

[0138] 15 associated temperature sensor 107a. An external failure status of each of the other pump assemblies 105], j e [b, c , is determined in a saturation mode routine in step 433 based on a received zone temperature deviation associated with said other pump assembly 105], j e [b, c , and a received current pump speed of said other pump assembly 105j, j e [b, c}.

[0139] 20 The determination of the external failure status of the other pump assemblies 105], j e [b, c , is explained in more detail in the saturation mode routine of step 433 in Fig. 5. It follows that the control method finally comprises with step 427 a step of controlling a variable pump speed depending on the zone temperature deviation and depending on the external failure status of the other pump assemblies 105], j e [b, c , and / or on its internal failure status.

[0140]

[0044] Fig. 5 describes the saturation mode routine of step 433 in more detail. The saturation mode routine is initialized in step 501 . In the following step 503, the dynamic zone temperature reference Tref is set to the

[0141] 30 previously determined dynamic zone temperature reference Tret. A pump index counter ] is initialized in following step 505. The pump index counter ] is increased in step 507. So, the saturation mode routine loops overall other pump assemblies 105], i.e. j e [b, c}. In step 509, it is checked

[0142] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 whether the received zone temperature deviation ATj and / or the received current pump speed coj is valid data. If not, the routine jumps to step 531 described below. If the received zone temperature deviation ATj and the received current pump speed coj represent valid data, it is

[0143] 5 checked in step 51 1 whether the received zone temperature deviation ATj and the received current pump speed coj are different from zero. If not, the routine jumps to step 531 described below. If said other pump assembly 105j is running and has a non-zero zone temperature deviation ATj, it is checked whether said other pump assembly 105j is running close to its maximum speed in step 513, e.g. above 90% of its maximum speed. If this is not the case, a saturation counter is reset in step 515. If said other pump assembly 105j is running close to its maximum speed while the zone temperature deviation ATj is non-zero, i.e. a said other pump assembly 105j is saturated, a saturation counter is increased in step 517. It is then

[0144] 15 checked in step 519 if the saturation counter exceeds a maximum saturation sample limit. If not, the routine jumps to step 531 described below. The rationale behind step 519 is that too many saturated pump assemblies 105j cannot be helped by increasing the share of the total thermal energy flow provided by the common thermal energy source 103. If the

[0145] 20 saturation counter exceeds the maximum saturation sample limit, it must be assumed that the total thermal energy provided by the common thermal energy source 103 is not sufficient for all pump assemblies 105a-c to deliver the required thermal energy flow into the building zones 1 , 2 and 3. It is next checked in step 521 whether the zone temperature deviation ATj is positive or not. If not, there is no need to help said other pump assembly 105j and the routine jumps to step 531 described below. If the zone temperature deviation ATj is positive, a dynamic saturation offset, e.g. -10%, is adjusted in step 523. In the following step 525, it is checked whether the rate of dynamic zone temperature reference changes ex¬

[0146] 30 ceeds a maximum limit. If this is the case, the dynamic saturation offset is limited to a maximum in order to prevent too much sacrifice of the pump assembly to help the other saturated pump assembly 107j. If not, the dynamic zone temperature reference Tref is set in step 529 to the target zone temperature Ttarget being reduced by the dynamic saturation

[0147] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 offset. In step 531 , it is checked if the loop has gone over all other pump assemblies 105j. If not, it repeats the steps starting at step 507 for the next other pump assembly 105j. If the loop over all other pump assemblies 105j is finished in step 531 , it is checked if the dynamic zone temperature ref¬

[0148] 5 erence Tret is below a user-defined zone temperature minimum. A user may set, by using the user control program on the remote-control device 1 1 1 , such a user-defined maximum zone temperature reduction, e.g. by 5°C, to guarantee a maximum zone temperature reduction in building zone 1 . If this is the case, the dynamic zone temperature reference Tref is set in step 535 to the user-defined target zone temperature Ttarget minus the user-defined maximum zone temperature reduction. So, setting the user-defined maximum zone temperature reduction to zero would effectively result in a user command for the pump assembly 105a not to participate in helping other saturated pump assemblies 105j. However, if

[0149] 15 there is room for reducing the dynamic zone temperature reference Tref below the user-defined target zone temperature Ttarget by less than the user-defined maximum zone temperature reduction, it is checked in step 537 if the dynamic zone temperature reference Tret is above the target zone temperature Ttarget. If so, the dynamic zone temperature reference

[0150] 20 Tret is set in step 539 to the target zone temperature Ttarget. This is useful to ensure a proper initialization of the dynamic zone temperature reference Tret not being above the target zone temperature Ttarget and / or to check if the target zone temperature Ttarget has dropped in the meantime. Finally, the saturation routine outputs the set dynamic zone temperature reference Tret in step 541 .

[0151]

[0045] Fig. 6 shows certain steps of an example of the inventive control method in more detail. The local pump control of the pump assembly 105a performs the steps 433, 435, 437, 439 and 443 during normal pump operation, i.e. when the pump assembly 105a is not in backup operation

[0152] 30 following the steps 413, 415, 417, 419 and 421 . The saturation mode routine of step 433 takes as input variables the zone temperature deviation ATj and a current pump speed coJzwherein j is a pump index of all the other pump assemblies 105b, c of the zone pumping system 100. A further

[0153] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 input parameter for the saturation mode routine in a step 433 is a target zone temperature Ttarget for building zone 1 . As shown in Fig. 6, a user may set the target zone temperature Ttarget for the building zone 1 by using the remote-control device 1 1 1 . In the embodiment shown in Fig. 6, the target

[0154] 5 zone temperature Ttarget is sent to the associated temperature sensor 107a and then forwarded to the associated pump assembly 105a. Alternatively, the target zone temperature Ttarget may be communicated directly to the pump assembly 105a. The output of the saturation mode routine in step 433 is the reference zone temperature Tret that is an input to following step 435 where the zone temperature deviation AT is calculated. A further input to step 435 is the measured temperature Tmeasured received from the associated temperature sensor 107a via the wireless communication network 109. The measured zone temperature Tmeasured is subtracted in step 435 from the reference zone temperature Tref to output

[0155] 15 the zone temperature deviation AT as input into step 437, where the FID controller routine is executed. The PID controller routine of step 437 includes integral anti-windup measures and slew-rate limitation measures that are not shown in Fig. 6 for simplicity. The PID controller routine of step 437 is a closed-loop control to reduce the zone temperature deviation

[0156] 20 AT by an adaptation of the pump speed a>. The output of the PID controller routine of step 437 may be an integer value ranging between 0 and 100 representing a pump speed a> relative to a maximum pump speed. In the following step 439, the safe mode routine is performed to check for zone overheating. Fig. 7 shows the safe mode routine of step 439 in more detail. The output of the safe mode routine of step 439 is either zero if the measured zone temperature Tmeasured exceeds a pre-determined threshold. Otherwise, the output of the PID controller routine in step 437 is passed on to step 443, in which the pump speed is validated and set as the latest trusted speed. For monitoring purposes, the validated set

[0157] 30 pump speed a> may be passed on to the remote-control device 1 1 1 to display the current pump speed a> for a user.

[0158]

[0046] Fig. 7 shows the safe mode routine of 439 in more detail. After an initializing step 701 , it is checked in step 703 whether the measured zone

[0159] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 temperature Tmeasure overshoots the target zone temperature Ttarget. If that is not the case, a safe mode flag is set to FALSE, so that the output of the RID control routine of step 437 is not changed. If, however, the measured zone temperature Tmeasured overshoots the target zone temperature Ttarget,

[0160] 5 the safe mode flag is set to TRUE and the output of the safe mode routine of step 439 is set to zero, i.e. the pump assembly 105a is switched off.

[0161]

[0047] Where, in the foregoing description, integers orelements are mentioned which have known, obvious or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present disclosure, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the disclosure that are described as optional, preferable, advantageous, convenient or the like are optional and do not limit the scope

[0162] 15 of the independent claims.

[0163]

[0048] The above embodiments are to be understood as illustrative examples of the invention. It is to be understood that any feature described in relation to any one embodiment may be used alone, or in combination with other features described, and may also be used in combination

[0164] 20 with one or more features of any other of the embodiments, or any combination of any other of the embodiments. While at least one exemplary embodiment has been shown and described, it should be understood that other modifications, substitutions and alternatives are apparent to one of ordinary skill in the art and may be changed without departing from the scope of the subject matter described herein, and this application is intended to cover any adaptations or variations of the specific embodiments discussed herein.

[0165]

[0049] In addition, "comprising" does not exclude otherelements or steps, and "a" or "one" does not exclude a plural number. Furthermore, charac¬

[0166] 30 teristics or steps which have been described with reference to one of the above exemplary embodiments may also be used in combination with

[0167] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 other characteristics or steps of other exemplary embodiments described above. Method steps may be applied in any order or in parallel or may constitute a part or a more detailed version of another method step. It should be understood that there should be embodied within the

[0168] 5 scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of the contribution to the art. Such modifications, substitutions and alternatives can be made without departing from the spirit and scope of the disclosure, which should be determined from the appended claims and their legal equivalents.

[0169] 10

[0050] List of reference numerals:

[0170] I prior art zone pumping system

[0171] 3 prior art heat source

[0172] 5a-c prior art pump assemblies

[0173] 7a-c prior art temperature sensors

[0174] 9 prior art wiring

[0175] I I prior art central controller

[0176] 100 inventive zone pumping system

[0177] 103 heat source

[0178] 20 105a-c pump assemblies

[0179] 107a-c temperature sensors

[0180] 109 wireless communication network

[0181] I I I remote-control device

[0182] 401 initializing step

[0183] 403 disabling thermal energy demand signal and increasing uncertainty counter

[0184] 405 checking for other running pump assemblies

[0185] 407 calculating average pump speed of other pump assemblies

[0186] 30 409 enabling thermal energy demand signal

[0187] 41 1 checking for a working communication connection with the associated temperature sensor

[0188] 413 setting backup operation flag to TRUE

[0189] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 415 checking for working communication connection with other pump assemblies

[0190] 417 updating pump speed to the latest trusted pump speed

[0191] 419 checking if the trust has been lost to the latest trusted pump

[0192] 5 speed

[0193] 421 updating pump speed relative to the trusted pump speed and pump speeds of other pump assemblies

[0194] 423 checking if the pump speed is above the minimum speed limit

[0195] 425 updating the pump speed to zero

[0196] 427 running the pump at the set pump speed

[0197] 429 updating pump speed and enabling thermal energy demand signal

[0198] 431 resetting the pump uncertainty counter

[0199] 15 433 executing the saturation model routine

[0200] 435 determining the zone temperature deviation

[0201] 437 executing the PID controller routine

[0202] 439 executing the safe mode routine

[0203] 441 setting the backup operation flag to FALSE

[0204] 20 443 validating the pump speed and updating the trusted speed

[0205] 501 initialization step

[0206] 503 setting dynamic temperature reference to previous temperature reference

[0207] 505 initializing the pump index counter

[0208] 507 increasing the pump index counter

[0209] 509 checking if the pump speed and zone temperature deviation is valid data

[0210] 51 1 checking if the pump speed and zone temperature devia¬

[0211] 30 tion is different from zero

[0212] 513 checking if the pump speed is close to the maximum speed

[0213] 515 resetting saturation counter

[0214] 517 increasing saturation counter

[0215] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025 519 checking if the saturation counter is greater than a maximum saturation sample limit

[0216] 521 checking if the pump has a positive zone temperature deviation

[0217] 5 523 adjusting the dynamic saturation offset

[0218] 525 checking if the rate of dynamic temperature reference changes exceeds a maximum limit

[0219] 527 limiting the dynamic saturation offset

[0220] 529 setting the dynamic reference zone temperature

[0221] 531 checking if loop over all other pump assemblies is finished

[0222] 533 checking if the dynamic reference zone temperature is below a user-defined zone temperature minimum

[0223] 535 checking if the dynamic reference zone temperature is above a target zone temperature

[0224] 15 539 setting the dynamic reference zone temperature to the target zone temperature

[0225] 541 outputting the set dynamic reference zone temperature

[0226] 701 initializing step

[0227] 703 checking if the measured temperature is overshooting the reference

[0228] 705 setting the save mode flag to FALSE

[0229] 707 setting the save mode flag to TRUE

[0230] 709 updating the FID controller output to zero

[0231] 25

[0232] Patentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025

Claims

Claims1. A control method for controlling a pump assembly (105a) being configured to be used as one of a plurality of pump assemblies (105a-c) for transporting thermal energy from a common thermal5 energy source ( 103) into a plurality of building zones, wherein each of the plurality of pump assemblies (105a-c) is associated with one of the building zones and configured to drive a zone-specific thermal energy flow from the common thermal energy source (103) into the associated building zone, wherein the method comprises the following steps carried out by said pump assembly (105a): providing a receiving opportunity to receive, via a wireless communication network (109), a zone temperature information from an associated zone temperature sensor (107a) being arranged at the building zone associated with said15 pump assembly (105a); determining or processing an associated zone temperature deviation (AT) based on the received zone temperature information; sending, via the wireless communication network (109), the20 associated zone temperature deviation (AT) and / or a current operating variable (co) of said pump assembly (105a) to the other pump assemblies ( 105j); determining an external failure status of each of the other pump assemblies (105j) based on a received zone temperature deviation (ATj) associated with said other pump assembly ( 105j) and / or a received current operating variable (coj) of said other pump assembly ( 105j), and / or determining an internal failure status; and controlling a variable pump speed (co) of said pump assembly30 ( 105a) depending on the zone temperature deviation associated with said pump assembly (105a) and depending on the external failure status of the other pump assemblies (105j) and / or the internal failure status. atentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 20252. The method according to claim 1 , wherein the zone temperature information is a measured zone temperature (Tmeasured) or the zone temperature deviation (AT), wherein the zone temperature devia¬5 tion (AT) is a difference between the measured zone temperature (Tmeasured) and a reference zone temperature (Tret), wherein the reference zone temperature (Tret) is based on a user-defined target zone temperature (Ttarget) minus a saturation offset which depends on the external failure status of the other pump assemblies ( 105j).10 3. The method according to claim 1 or 2, wherein the current operating variable (co) is an absolute or relative value being indicative of a current pump speed (co) and / or current pump power consumption.

4. The method according to any of the preceding claims, wherein the15 internal failure status and / or the external failure status of the other pump assemblies (105j) is a saturation status or a communication status, or a combination of the saturation status and the communication status.

5. The method according to any of the preceding claims, wherein the20 variable pump speed (co ) of said pump assembly ( 105a) is reduced if the external failure status of one or more of the other pump assemblies ( 105j) indicates a saturation.

6. The method according to claim 5, wherein the variable pump speed (co) is reduced by an absolute or relative reduction amount25 that depends on the zone temperature deviation(s) (ATj) associated with the one or more other pump assemblies ( 105j) with an external failure status that indicates saturation.

7. The method according to any of the preceding claims, wherein the variable pump speed (co ) of said pump assembly ( 105a) is controlled atentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025based on a pump speed (coj) of the other pump assemblies ( 105j) if the internal failure status indicates a failing communication with the associated zone temperature sensor (107a).

8. The method according to claim 6 or 7, wherein the variable pump5 speed (co) of said pump assembly (105a) is controlled based on a latest pump speed before the communication failed if the internal failure status indicates a failing communication with all of the other pump assemblies ( 105j).

9. The method according to any of the preceding claims, further com¬10 prising configuring each of the pump assemblies (105a-c), via the wireless communication network (109), by a user application being executed on a remote-control device (1 1 1 ).

10. The method according to any of the preceding claims, wherein a Matter® Smart Home Communication Standard Version 1 .3 or later is used as a communication protocol for communicating via the communication via the wireless communication network (109).1 1 . The method according to any of the preceding claims, wherein the step of controlling the variable pump speed (co) includes setting the variable pump speed (co) to zero if the zone temperature infor¬20 mation indicates a zone overheat in excess of a pre-determined relative or absolute overheat tolerance in the associated building zone.

12. The method according to any of the preceding claims, further comprising sending a thermal energy demand signal to the common25 thermal energy source (103).

13. The method according to any of the preceding claims, wherein the steps of the method according to any of the preceding claims are carried out by each of the plurality of pump assemblies (105a-c). atentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 202514. A computer program comprising instructions which, when the program is executed by a pump assembly (105a-c), cause the pump assembly (105a-c) to carry out the steps of the method according to any of the preceding claims.5 15. A user application program comprising instructions which, when the program is executed by a remote-control device (1 1 1 ), configures a pump assembly (105a-c) via the wireless communication network ( 109) to carry out the steps of the method according to any of the claims 1 to 13.10 16. A remote-control device (1 1 1 ) being configured to execute a user application program according to claim 13.

17. A pump assembly ( 105a) being configured to be used as one of a plurality of pump assemblies (105a-c) for transporting thermal energy from a common thermal energy source into a plurality of building zones, wherein the pump assembly (105a) is configured to be associated with one of the building zones and configured to drive a zone-specific thermal energy flow from the common thermal energy source into the associated building zone, wherein the pump assembly (105a) is configured to carry out the steps of the method20 according to any of the claims 1 to 13. atentanwdlte Hemmer Lindfeld Frese GP 3825 WO, 06 / 10 / 2025

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