Method for monitoring and / or controlling a heating system

Abstract

The invention relates to a method for monitoring and / or controlling a heating system, comprising a line network having a variable system resistance and at least one heat source for feeding a heating medium having a defined initial flow temperature into the line network and at least one circulation pump for circulating the heating medium within the line network, the method has the method steps of determining a current start flow and / or return flow temperature, determining a current equipment resistance of the pipeline network, and calculating a correlation value between the current start flow and / or return flow temperature and the current equipment resistance.

Description

Technical Field

[0001] The invention relates to a method for monitoring and / or controlling a heating installation comprising a pipeline network with a variable installation resistance, at least one heat source for feeding a heating medium with a defined initial flow temperature into the pipeline network, and at least one circulation pump for circulating the heating medium in the pipeline network. Background Art

[0002] Central heating is usually used to heat homes or other buildings. After the medium flowing through the pipeline network passes through the radiator that can be controlled by means of a thermostatic valve, it is returned to the heat source by return flow. The heat source, in particular the heating boiler, heats the medium to a specific initial flow temperature. The circulation pump is responsible for the discharge flow.

[0003] The setpoint flow or return temperature of a central heating system is set by a heating control, wherein in practice an ambient temperature-guided setting of the flow temperature has proven itself. The heating control typically receives the current ambient temperature via a sensor signal, which serves as an indicator of the expected heat demand for the area to be heated. The heating control receives the setpoint presetting for the flow or return temperature to be set via a stored heating curve, which specifies the corresponding setpoint temperature for the flow or return as a function of at least one operating parameter, here the current ambient temperature.

[0004] Such heating curves are usually building-specific and can therefore be modified by the operator of the installation in order to be able to set the temperature control device as required. In addition, not only the steepness of the heating curve can be specified but also a possible offset can be specified as an option. A heating curve that is set too flat results in an insufficient heat supply to the building at low temperatures. In contrast, in the case of a curve that is set too steep, although sufficient heat supply to the building is ensured, the energy consumption is unnecessarily greatly increased due to boiler and line losses.

[0005] Even in the case of a heating curve that is perfectly set to the current outside temperature, it can be assumed that energy is still consumed unnecessarily, because the signal of the outside temperature is not directly related to the heating demand. Thus, for example, at low temperatures but strong sunlight, the heat demand is lower than at higher temperatures and in windy or cloudy weather. For this reason, internal heat and cold sources (electrical devices such as ovens, computers, etc., as well as large crowds or open windows) can further influence the demand.

[0006] In summary, the following two weaknesses can be found in the heating control based on the outside temperature that has been used to date:

[0007] - Heating curves are building specific and most are set too steeply

[0008] The heating demand can only be derived suboptimally from the outside temperature. Summary of the invention

[0009] The object of the present invention is to specify an improved possibility for controlling the temperature of a circulating heating medium which overcomes the above-mentioned disadvantages.

[0010] According to the invention, this object is achieved by a method according to the features of claim 1. Advantageous embodiments of the method are the subject matter of the dependent claims. The invention is also achieved by a circulating pump, a heat source and / or a heating system according to the features of claims 15 to 16.

[0011] According to the invention, a method is proposed, in which the current flow temperature and / or return temperature of a heating medium circulating in a pipeline network is first determined. The flow temperature is understood to be the temperature of the heating medium immediately downstream or at least in the vicinity of the heat source before it flows through a heat exchanger or radiator. The return temperature is understood to be the temperature of the heating medium when it flows back from the pipeline network to the heat source, i.e. preferably immediately upstream of the heat source. The design of the heat source is arbitrary and can, by way of example, include a burner, a condensing boiler heating device, a heat pump, etc.

[0012] In addition to the temperature detection, according to the invention, the system resistance of the pipeline network is also determined, for example measured, or calculated or estimated based on other operating data. In the case of heating circuits with integrated accessories, such as valves, in particular thermostatic valves, the system resistance of the pipeline network is dynamic and consists of a static and a dynamic component. The static component is determined by the pipeline resistance of the pipeline network. The dynamic component depends on the possible position of accessories, in particular the position of valves in the system, that is, mainly on the opening of the installed valves, in particular the thermostatic valves of the individual radiators or other heat exchangers in the system. Since the opening of the valves, in particular the thermostatic valves, characterizes the current heat demand in the corresponding room, the current heat demand can be inferred from the system resistance, in particular the dynamic component.

[0013] The inventors have recognized that there is a certain correlation between the medium temperature and the device resistance. This knowledge makes it possible to determine by monitoring two values ​​whether the heating device is operating under optimal conditions, in other words whether the device can meet the required heat demand, but at the same time does not consume energy unnecessarily. According to the invention, it is therefore proposed to determine relevant values ​​based on specific raw and / or return flow temperatures and specific device resistances, which make it possible to evaluate the operating conditions and the efficiency of the device. In other words, with the help of this method, it is possible to identify, for example, whether the current regulation of the heating device, in particular the heat source, can meet the current heating demand, but does not consume energy unnecessarily. For example, this enables a wide range of possibilities for controlling the device, such as heating regulation supplemented by external temperature guidance, which can also be used. In an ideal case, there is even the possibility of abandoning the external temperature as a guiding variable, whereby the use and installation of external temperature detection elements becomes redundant.

[0014] Preferably, provision can be made that the method provides for an evaluation of the current feed and / or return flow temperature, for example to determine whether the current set feed and / or return flow temperature is too high or too low, in order to ensure an optimally efficient heating operation.

[0015] The current flow or return temperature can be determined by sensing, i.e. by at least one integrated sensor in the corresponding line section. It is also possible to use a sensor installed in the circulation pump. It is also conceivable to determine the flow and / or return temperature by an estimation algorithm or to calculate it indirectly based on other operating parameters. The estimation algorithm uses, in particular, operating parameters of the pump, such as the current pump speed and / or torque of the pump drive train, and is therefore meaningfully executed on or by the circulation pump.

[0016] The current system resistance can theoretically be detected by measurement technology. However, it is preferred to calculate the system resistance using the discharge flow Q of the heating medium in the system and / or the hydraulic pressure. The last-mentioned parameters are present, for example, in the circulation pump or the heating control, so that it is possible to calculate the system resistance for the current operating point. For example, the discharge flow and the head of the pump can be determined in a sensory manner. However, it is also conceivable that these values ​​are also calculated as a function of other operating parameters of the circulation pump, such as the current power consumption and the rotational speed of the pump drive. In this case, it is also conceivable to use an estimation algorithm for determining the discharge flow and the head, the limiting system resistance.

[0017] According to a particularly preferred embodiment of the invention, the correlation value is determined by the ratio of the current flow or return temperature to the current device resistance. In this regard, it is meaningful to determine the correlation value continuously over time. However, the correlation value can also be detected alternatively only in a specific time segment or repeatedly in a cycle.

[0018] It is useful to continuously monitor the relevant values ​​in order to be able to determine temporal changes in particular. Temporal changes, key words night changes, occur in particular when the energy demand of the space to be heated or the operating point of the heating changes. Based on this temporal development of the relevant values, it can be determined whether the current feed and / or return flow temperatures allow efficient system operation.

[0019] As already stated in the introduction to the description, the heat source or the internal temperature control device can take into account a heating curve which predetermines the setpoint temperature for the feed and / or return flow as a function of at least one parameter, in particular the ambient temperature. If this is the case, the heating curve used can be evaluated by evaluating the relevant values ​​determined according to the invention.

[0020] In the case of an optimal heating curve, an ideal flow or return temperature will always be set under all possible operating conditions, which meets the current heating demand but does not consume energy unnecessarily. However, if the heating curve is set too steeply, i.e. the flow temperature will be set too high for the current heating demand, the thermostatic valve must throttle off the excess heat input, whereby the system resistance increases. The ratio between the flow / return temperature and the system resistance and thus the related values ​​change.

[0021] With this knowledge, it is now possible to evaluate the currently used heating curve and, if necessary, to adapt it in order to further optimize the heating operation.

[0022] If, for example, a change in the relevant value or a specific minimum value of the change in the relevant value is determined, the slope and / or the offset value of the heating curve are evaluated as being too low. The evaluation result can be provided, for example, in the form of an action recommendation for adapting the heating curve as electronic information, which can be communicated to any external device. Visual or acoustic information display of the results is also conceivable. For example, if the method is completely performed by a circulating pump, such an operating method makes sense and is conceivable. However, instead of or in addition to the information output, the method can also provide for automatic adaptation of the heating curve in order to increase its parameters, in particular the slope and / or the offset value. If the relevant value determined within a specific duration does not change or the change is only within a tolerable range of variation and the relevant value is also greater than a definable limit value, the slope of the heating curve can be evaluated as being too large. In this case, the heating curve can be automatically adapted to reduce the slope of the curve.

[0023] If, however, the relevant value remains constant or lies within the tolerance band and the value of the relevant value does not exceed the aforementioned limit value, an optimally or at least sufficiently well set heating curve is assumed. In this case, the heating curve is not adapted.

[0024] The above-mentioned embodiments relate to the adaptation of the heating curve of the heating control. However, the important basic idea of ​​the invention of the present application can also be applied to such heating regulation that is not guided by the outside temperature or performs the regulation of the flow temperature without using the stored heating curve. Under such preconditions, the method can also be used meaningfully; more precisely, the method makes the detection and consideration of the outside temperature superfluous when necessary. For example, it is conceivable that the heating control device initially adjusts the flow and / or return flow temperature to a predefined rated value. Then, the subsequent adaptation of the flow temperature is carried out only or at least decisively by specific relevant values, which make it possible to accurately state the current heating demand. In this case, for example, an external sensor for detecting the outside temperature of the building can be abandoned, and instead, regulation can be carried out only based on the proposed method according to the present invention. However, it is also conceivable that, in addition to the method according to the present invention, other parameters are also considered for setting the flow and / or return flow temperature.

[0025] It is also conceivable that the method according to the invention is not used, or at least not only in normal operation, but instead a test program can be performed during which the flow temperature is manipulated in a targeted manner in order to determine the behavior of the device, in particular the change in the device resistance, based on this. For example, this operating method can realize a targeted optimization process or a learning function for setting the operating parameters of the heating control device. The method according to the invention can also be combined with any other control functions of the heating control device or these already implemented control functions can be superimposed. Similarly, the type and scale of the automatic adaptation of the heating curve can be set by one or more configurable parameters. In this regard, it is conceivable that a configurable risk factor is provided for adapting the variation margin of the heating curve. When a high risk factor is configured, after the heating curve is evaluated, a higher numerical change of the heating curve, in particular the slope and / or the offset value, is allowed, while in the case of a smaller risk factor configured, only a smaller adaptation of the heating curve is allowed. Alternatively or in addition thereto, an occupant feedback function can be implemented, which detects feedback from the occupants of the building to be heated by means of corresponding input devices, in particular by means of operating devices at the pump and / or heating control device and / or by means of external communication devices, such as a smartphone or tablet with an installed application, and takes this into account for further method execution. Thus, a manual evaluation of previously performed adaptations of the heating curve can be taken into account and included for future adaptations.

[0026] The invention also relates to a pump, in particular a centrifugal pump, having a pump control, which is configured to carry out the method according to the invention, wherein the pump is preferably communicatively connected to a heating control of a heat source via at least one interface in order to be able to evaluate and / or adapt the heating curve. The invention also relates to a heat source, in particular a burner / heating boiler, having an internal heating control, which is configured to carry out the method according to the invention, wherein the heat source is preferably communicatively connected to a circulation pump of a heating installation via at least one interface in order to be able to evaluate and / or adapt the heating curve.

[0027] The present invention also includes a heating device, which has at least one pump and a heat source, wherein the pump and / or the heat source each have a control device and / or a central control device, which is configured to perform the method according to the present invention. The execution of the method or the individual method steps can be performed entirely by a pump control device or a heating control device. However, distributed method execution is also conceivable, in which sub-steps are performed not only on the pump control device but also on the heating control device. In addition, there is the possibility of providing a separate central device control device, which fully or at least partially performs the necessary method steps with or without the support of the pump and / or the heat source. For the distributed execution of the method steps, it is naturally necessary that the individual control devices, in particular the pump control device and / or the heating control device, can communicate with each other via suitable interfaces. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Other advantages and features of the present invention will be explained in more detail below based on the embodiments shown in the accompanying drawings.

[0029] Figure 1 A diagram showing the time course of the starting flow temperature and the system resistance in a heating system,

[0030] Figure 2 a graph showing the time course of the calculated correlation values, and

[0031] Figure 3 A schematic diagram shows a flow chart of the method according to the invention. DETAILED DESCRIPTION

[0032] The method according to the invention will be explained by way of example using a heating system which comprises, for example, a combustion boiler as a heat source and which sets the starting flow temperature according to a heating curve. The heating medium is circulated in the pipeline network by means of a heating circulation pump which conveys the medium in a circuit in such a way that the operating point depends on the discharge flow and a certain head. The system resistance is influenced by the valve position of the individual thermostatic valves of the radiator.

[0033] In this embodiment, the method is primarily carried out by the overall pump control of the heating circulation pump. According to the core idea of ​​the invention, the heating pump determines the actually existing heat demand in the heating installation and, for example, provides this information to the heating control of the burner for adapting the initial flow temperature control. The heating control then either sets the initial flow temperature solely according to the demand determined by the pump, or it combines the demand determined by the pump with the signal of the ambient temperature.

[0034] To determine the instantaneous heat demand, the following parameters are available to the pump:

[0035] - Start flow temperature: The start flow temperature is determined by the pump either via an external sensor or by internal estimation.

[0036] -设 Reserve resistance ζ: 设 The equipment resistance ζ describes the sum of the losses in the pipeline and the losses of all thermostatic valves. Since the losses in the pipeline are constant, the position of the thermostatic valve can be directly inferred from the equipment resistance ζ. The equipment resistance is calculated as follows:

[0037] ζ=H / Q

[0038] In this case, the delivery flow Q and the head H are typically determined by the pump control by means of internal estimation algorithms.

[0039] Crucial is the given correlation between the set flow temperature and the system resistance. If the heating curve is set optimally, all weather influences will be compensated by the flow temperature control and the flow temperature signal will be completely independent of the course of the system resistance. If, however, the heating curve is set too steeply, the thermostatic valve will throttle off the excess heat input, which is indicated by an increase in the system resistance.

[0040] Here, it was possible to determine from laboratory studies that, in the case of a heating curve that is only slightly too steep, the system resistance follows the initial flow temperature. Figure 1 The time evolution of the initial flow temperature and the equipment resistance is shown in FIG.

[0041] In the studied building, switching between day and night mode was performed, which could be seen by the sudden changes in the initial temperature. Switching to night mode was not set in the time period between 60 hours and 120 hours (e.g. at weekends). Figure 1 It can be clearly seen that the signal of the system resistance follows the course of the starting flow temperature. The reason for this is that at high starting flow temperatures, the thermostatic valve must be closed in order to keep the room temperature constant. The closed valve leads to an increase in the system resistance. The influence of the starting flow temperature on the system resistance is dominant over other influences such as a window that is opened for a short time.

[0042] Due to the high correlation between the flow temperature and the system resistance, an approximately constant factor can be derived between the flow temperature and the system resistance, which factor can be calculated, for example, as follows:

[0043] Related value = initial flow temperature / equipment resistance

[0044] Figure 2 It is shown by way of example Figure 1 The resulting course of this correlation value of the determined measured value. The diagram shows, apart from tolerable fluctuations, an almost constant course of the correlation value. The correlation value is proportional to the value around which the heating curve is set too steeply. The heating control can therefore deduce from the signal of the correlation value whether the heating curve is set too steeply or too flat.

[0045] In this case, the following guidelines can be followed:

[0046] Case 1: Correlation value is not constant -> Heating curve is too flat:

[0047] If the relevant value should not be constant, the thermostatic valve does not follow the start flow temperature. This indicates a heating curve that is too flat. The heating curve must be steeper.

[0048] Case 2: The correlation value is constant, the correction value is large -> the heating curve is too steep:

[0049] If the correction value is constant, the heating curve is not too flat and the building is supplied with heat sufficiently. However, if the relevant value is large in value, this indicates that the building is oversupplied and energy consumption is unnecessarily increased. The heating curve must be set flatter.

[0050] Case 3: Correlation value is constant, correction value is small -> heating curve is perfect:

[0051] A constant correlation value means that there is no undersupply and the heating curve is not set too flat. If the value of the correlation value is small for this, the heating curve is not too steep. In this case, heating is performed optimally.

[0052] Figure 3The control process described previously is again schematically shown. In frame 10, the initial flow temperature and the system resistance are first determined. The course of the relevant values ​​is monitored over a specific period of time, in particular continuously. If the course of change is approximately constant, the method turns to frame 20, which determines the level of the relevant value. If the relevant value is above a specific limit value, the method is continued with frame 30. It is provided here that the heating curve must be adjusted steeper, and the pump communicates this to the heating control device via an interface. If, on the other hand, the determined relevant value is low and below the limit value, the currently used heating curve is evaluated as optimal and is not modified. The method returns to frame 10.

[0053] If, however, it is detected in block 10 that the relevant value is not constant, the method passes to block 40. In this case, a message is transmitted to the heating control device, according to which the heating curve must be adjusted steeper in order to be able to meet the heat demand in the building.

Claims

1. A method for monitoring and / or controlling a heating installation, the heating installation comprising a pipeline network with a dynamically variable installation resistance, at least one heat source for feeding a heating medium with a defined initial flow temperature into the pipeline network, and at least one circulation pump for circulating the heating medium in the pipeline network, the method comprising the following method steps: - determine the current flow and / or return temperature, - determine the current equipment resistance of the pipeline network, - Calculation of correlation values ​​between the current flow and / or return temperature and the current system resistance.

2. The method according to claim 1, It is characterized in that The feed and / or return flow temperature is evaluated as a function of the calculated correlation value and / or a set target value for the feed and / or return flow temperature is adapted.

3. The method according to any one of the preceding claims, It is characterized in that The raw flow temperature is determined by means of a sensor and / or by estimation, in particular by estimation of a pump.

4. The method according to any one of the preceding claims, It is characterized in that The installation resistance includes losses in the pipelines of the heating installation and losses in the thermostatic valves of one or more radiators of the heating installation.

5. The method according to any one of the preceding claims, It is characterized in that The plant resistance is determined based on the detected delivery flow and the resulting head of the circulation pump.

6. The method according to claim 5, It is characterized in that The delivery flow and / or the head are determined in a sensory manner and / or by an estimation algorithm, in particular by the circulation pump.

7. The method according to any one of the preceding claims, It is characterized in that The correlation value is determined by the ratio of the initial flow temperature to the device resistance.

8. The method according to any one of the preceding claims, It is characterized in that The temporal variation of the correlation value is monitored.

9. The method according to any one of the preceding claims, It is characterized in that The flow rate controlled by the heat source is set taking into account a heating curve which specifies the flow rate as a function of at least one parameter, in particular the ambient temperature, and which is evaluated and / or adapted taking into account the relevant values.

10. The method according to claim 9, It is characterized in that In the event of a determined change in the relevant value, in particular a change of at least one specific value, an adaptation of the heating curve, in particular an adaptation of the curve slope of the heating curve and / or an offset value of the heating curve, is suggested and / or carried out.

11. The method according to any one of claims 9 or 10, It is characterized in that If the correlation value remains constant or changes only within a tolerance band and the correlation value exceeds a definable limit value, the slope of the heating curve is reduced.

12. The method according to any one of claims 9 to 11, It is characterized in that If the relevant value is constant or varies only within a tolerance band and does not exceed a defined limit value, the heating curve is not adapted and / or is not evaluated as optimal.

13. The method according to any one of the preceding claims 1 to 8, It is characterized in that The heat source initially adjusts the flow temperature to a predetermined value and a subsequent adaptation of the flow temperature takes place only or predominantly taking into account the relevant value.

14. The method according to any one of the preceding claims, It is characterized in that The method is performed on a circulation pump of the heating installation and / or by a heating control of the heat source, wherein the circulation pump and the heat source are preferably connected via a communication interface for exchanging one or more parameters.

15. The method according to any one of the preceding claims, It is characterized in that The method repeatedly or upon request carries out a test sequence during which the raw flow temperature is manipulated in a targeted manner.

16. A pump, in particular a heating circulation pump, having a pump control device, which is configured to perform a method according to any of the preceding claims, wherein the pump is preferably communicatively connected to the heating control device of the heat source via at least one interface in order to evaluate and / or adapt the heating curve.

17. A heat source, in particular a heating boiler, having an internal control device, which is configured to perform a method according to any of the preceding claims, wherein the heat source is preferably communicatively connected to a circulation pump via at least one interface in order to evaluate and / or adapt a heating curve. 18 . A heating installation having at least one pump and a heat source, wherein a pump control of the pump and / or a heating control of the heat source is configured to carry out the method according to claim 1 .

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