EP3508730A1 - Method for adjusting a pressurisation system - Google Patents

Abstract

Method for setting a proportional pressure control curve (1) in the control electronics of a pressure booster for supplying a hydraulic network in a building with a number of sampling points. The control electronics already determine from three plant values, which
a volume flow value (q _100% ) of a desired maximum volume flow on the pressure control curve (1),
- a height value (H _geo ) of a geodetic altitude and
comprise a flow pressure value (p _FL ) of a desired flow pressure at the most unfavorable sampling point,
a minimum pressure (p _{Q = 0} ) at zero flow rate and a maximum pressure (p _Q100% ) at the maximum flow rate. The pressure control curve (1) is formed by a connecting line between the minimum pressure (po = o) and the maximum pressure (p _Q100% ) and is set by the control _electronics .

Description

The invention relates to a method for setting a proportional pressure control curve in the control electronics of a pressure booster for supplying a hydraulic network in a building with a number of tapping points. The invention further relates to a pressure booster for carrying out the method.

Pressure increase systems are pumping stations with one or more parallel pump units and are mainly used in drinking water supply. They increase the pressure of the drinking water provided by a supplier and thus convey it via a pipeline system to all removal points, such as taps, toilets, or showers. It must be ensured that sufficient pressure is always present at each sampling point so that the drinking water flows out of the sampling point. The actual pressure at the consumer is usually not known, so that the pumping station is always chosen so oversized and exaggerated high, that even with unfavorable system conditions, for example, simultaneously opened tapping points, the worst-supplied tapping point is always adequately supplied.

It is known in pressure boosting systems to control to a constant, predetermined output pressure, which is kept constant even with fluctuations in the supply pressure regardless of the volume flow through the pumping station. This is known as pc control ( p _soll = constant). However, such a constant pressure control leads to an energetically not optimal operation, since the pressure losses with the volume flow increase ( p _V ~ Q ). Thus, depending on the flow Q, a different amount of flow pressure p _{FL is available} for use at a sampling point. Around To avoid this disadvantage, it is also known to use a proportional pressure curve, along which the pressure booster _is controlled, so that a desired pressure curve p set = f ( Q ) is present at the output of the pressure booster, ie, a so-called p -v control. Such a proportional pressure control curve is also more comfortable for the user because it leads to lower pressure fluctuations at the sampling points.

For a suitable and energy-optimal adjustment of a p -v control curve at the pressure booster system knowledge of the pressure losses p _V in the hydraulic network is required, in particular at least those pressure losses that occur from the pressure booster over the pipeline network to the hydraulically unfavorable sampling point. These are described by the so-called plant curve, also called building characteristic or system characteristic. However, the actual pressure losses are usually not known, especially in the case that a new pressure booster system is installed in an existing building. An optimal setting of the pressure booster is difficult here.

Methods are known for determining a plant curve. However, these methods are complex, require some knowledge of the structure of the hydraulic network, calculations or measurement evaluations and are therefore usually carried out only by qualified personnel. Frequently, the pressure losses are estimated, which involves a high degree of uncertainty about a correct setting of the pressure booster.

It is therefore an object of the present invention to provide a simple method for setting a proportional pressure control curve in the control electronics of a pressure booster available that can be performed quickly and by untrained people and leads to a user-friendly setting of the pressure booster.

This object is achieved by a method having the features of claim 1. Advantageous developments are specified in the subclaims.

• einen Volumenstromwert (Q_100%) eines gewünschten Maximalvolumenstroms auf der Druckregelkurve,
• einen Höhenwert (H_geo) einer geodätischen Höhe und
• einen Fließdruckwert (p_FL) eines gewünschten Fließdrucks an der ungünstigsten Entnahmestelle umfassen,
  einen Minimaldruck (p_Q=0) bei Volumenstrom null und einen Maximaldruck (p_Q100%) bei dem Maximalvolumenstrom ermittelt, wobei die Druckregelkurve durch eine Verbindungslinie zwischen dem Minimaldruck (p_Q=0) und dem Maximaldruck (p_Q100%) gebildet ist und von der Regelungselektronik eingestellt wird.

According to the invention, a method for adjusting a proportional pressure control curve in the control electronics of a pressure booster system for supplying a hydraulic network in a building with a number of sampling points is proposed, in which the control electronics already from three assets, which

• a volume flow value (Q _100% ) of a desired maximum volume flow on the pressure control curve,
• a height value (H _geo ) of a geodetic altitude and
• comprise a flow pressure value (p _FL ) of a desired flow pressure at the most unfavorable sampling point,
  a minimum pressure (p _{Q = 0} ) at zero flow and a maximum pressure (p _Q100% ) determined at the maximum flow, wherein the pressure control _{curve is} formed by a connecting line between the minimum pressure (p _{Q = 0} ) and the maximum pressure (p _Q100% ) and is adjusted by the control electronics.

This method allows the setting of a suitable pressure control curve on the pressure booster without requiring any user to know the pressure losses in the hydraulic network. Three system values for the setting are already sufficient. These are easy to determine, so the process is very user-friendly.

The first plant value, the maximum volumetric flow, is the nominal flow that is to be present at the highest extraction point located in the building when a water is withdrawn.

In the context of the invention, a building is understood to mean a building which comprises one or more covered rooms, can be entered and serves the purpose of keeping people, animals or the storage of objects. The rooms do not necessarily have to be closed on all sides. The building can have any number of floors and extend in height or in depth. Also, the use of the building for private, public or industrial purposes is arbitrary. For example, but not necessarily, the building may include a residential building, an apartment building, an office building, a skyscraper, a public Facility such as a school, a library, a hospital, a gym, etc. The building can also be part of a complex of buildings, such as an airport or an exhibition center.

The hydraulic network may extend horizontally and / or vertically. It can span the entire building or only part of the building. In the latter case, for example, not all rooms have tapping points but only some rooms. Further, in the case of a multi-level building, the hydraulic network may extend only over some of the floors, i. not across all floors. In addition, the hydraulic network can also extend over two or more buildings, as is the case for example with housing complexes comprising several houses, or with row houses.

As unfavorable removal point that removal point of the network can be considered until the achievement of a conveyed medium from the pressure booster considered the largest pressure losses. For example, the most unfavorable removal point may be that withdrawal point which is highest in the building or furthest away from the push-pull system.

The volume flow value (Q _100% ) preferably forms a factory-set default value whose confirmation or change the control electronics expects. The volume flow value therefore does not have to be specified by the user. Rather, the control electronics in turn suggests the volume flow value, which is formed by the factory set and stored default value. The user can accept or change this default value and thus specify accordingly. Thus, the first asset value on the part of the user requires neither knowledge of the pressure booster system nor knowledge of the hydraulic network.

The change of the default value for the volume flow value can advantageously be limited by the control electronics to a certain range of change in order to avoid that the user sets a meaningless value by the change.

Suitably, the default value corresponds to the flow rate at maximum hydraulic power of the pressure booster. The default value is thus based on the characteristic curve field of the pressure increase system in the HQ diagram on the maximum pump curve. This ensures that along the pressure control curve the entire performance of the pressure booster can be exploited.

Alternatively or in addition to the default value, it may be provided that the user freely specifies the volume flow value. Thus, the volume flow value (Q _100% ) can form a user-definable input value, the input of which the control electronics expects. This allows an individual adaptation of the pressure increase system according to the user's request. In addition, the default value can be displayed to the user as a suggestion or reference value by the control electronics.

The second asset value is the geodetic height. For the purposes of the present invention, the geodetic height refers to the difference in height between the pressure booster and the highest extraction point.

Preferably, the height value (H _geo ) forms an input value to be preset directly by a user whose input the control electronics expects. This height value is a size that can be easily determined on the building.

Alternatively it can be provided that the height value (H _geo ) is determined from another information that indicates a user of the control electronics. Here are many variants possible.

For example, the height value can be determined from a building height specified by the user whose input the control electronics expect. This then calculates the height value, for example from the assumption that the pressure booster system is installed in the basement and the highest extraction point is on the top floor. In the simplest case, the building height as Altitude value for the geodetic height can be assumed, since the extent to which the building height must be increased due to the installation of the pressure booster in the basement, corresponds approximately to the extent to which the building height must be reduced due to the position of the highest removal point on the upper floor. Preferably, it can be provided that the user can manually change the ascertained altitude value.

Alternatively, the height value (H _geo ) can be determined from a floor number specified by the user. For this purpose, in the control electronics per floor with a fixed floor height such as 3m can be expected. In order to improve the accuracy of the determination of the height value, the floor height can be specified in addition, the input of the control electronics expected. Thus, the height value is determined from the number of floors and the floor level.

Preferably, the pressure value (p _FL ) form a factory default value whose confirmation or change expected the control electronics. This pressure value can be, for example, between 1bar and 3bar. The pressure value does not have to be specified by the user. Rather, the control electronics in turn proposes the pressure value, which is formed by the factory set and stored default value. The user can accept or change this default value and thus specify accordingly. Thus, even with the third asset value on the part of the user neither knowledge of the pressure booster system nor knowledge of the hydraulic network is required.

The change of the preset value for the pressure value can be advantageously limited by the control electronics to a certain range of change in order to avoid that the user sets a meaningless value by the change.

Alternatively or in addition to the default value, it may be provided that the user specifies the pressure value freely. Thus, the pressure value can form a user-definable input value whose input the control electronics expects. This allows an individual adaptation of the pressure increase system according to the Desire of the user. In addition, the default value can be displayed to the user as a suggestion or reference value by the control electronics.

In one embodiment variant, a geodetic pressure value (p _geo ) is calculated from the altitude value (H _geo ) or the altitude value is converted into the pressure value. Subsequently, the minimum pressure (p _{Q = 0} ) is formed from the sum of this geodetic pressure unit (p _geo ) and the flow pressure value (p _FL ). The minimum pressure forms the lowest point of the pressure control curve to be set, which is thus fixed.

In one embodiment, a maximum pressure _loss (Δp _{loss, max} ) is calculated from the volume flow value (Q _100% ) based on a trend function (T1-T5), and the maximum pressure (p _Q100% ) is calculated from the sum of the minimum pressure (p _{Q = 0} ) and the maximum pressure _loss (Δp _{loss, max} ) is formed. The maximum pressure forms the highest point of the pressure control curve to be set, which is thus likewise established. As a result, thus the entire pressure control curve is fixed and can be adjusted by the control electronics.

A trend function in the sense of the present invention describes the dependence of the maximum pressure _loss (Δp _{loss, max} ) on the volume flow (Q) according to a root function. Such a trend function can be determined empirically, for example by means of a standard-compliant pipe sizing and the pressure loss calculation according to generally known references in a hydraulic network, by means of which the system characteristic curve can be determined. This way, each pipe sizing can be assigned a specific trend function. If the pipe dimensioning corresponds to a specific design standard, a particular trend function can thus also be assigned to this particular design standard.

Due to the temporally different validity of the design standards, there is advantageously a relationship between the design standard used and the age of the building. This means that a building age can also be assigned or assigned a specific trend function.

The trend functions for different pipe dimensions or different design standards differ in particular only by their slope, which can be described by a factor. From this knowledge, the trend function can advantageously describe the dependence of the maximum pressure _loss (Δp _{loss, max} ) on the volume flow (Q) according to a root function whose slope is defined by a selectable design factor (k _A ). Thus, the design factor determines the slope of the trend function, so that only a single trend function needs to be stored in the control electronics. This can be done as a value table or as a function.

By default, a predefined mean value of the design factor (k _A ) can be used to determine the trend function and to calculate the maximum pressure loss.

However, higher accuracy can be achieved by adapting the trend function, or its slope, to the hydraulic network in the building, using the design factor. For this purpose, the fact can advantageously be exploited that the age of the building correlates with a specific design standard and consequently with a specific trend function. Thus, each building age can be assigned a design factor (k _A ), which causes a corresponding adaptation of a stored reference trend function (trend function for k _A = 1) to the building.

Preferably, it can be provided in the inventive method that the control electronics expected the specification of the building age of the building and then selects the design factor (k _A ) from a number of stored design factors based on the user entered building age. The corresponding trend function, the slope of which is defined by the selected design factor (k _A ), is then used to calculate the maximum pressure loss.

The age of the building is also an easily determinable quantity for which the user has neither technical knowledge of the characteristics of the pressure booster system nor knowledge of the hydraulic network of the building needed. It can thus be set in a simple manner and with few input variables for the building or the hydraulic network energetically good proportional pressure control curve in the pressure booster system, the control electronics of the pressure booster does this themselves.

The invention also relates to a pressure booster for supplying a hydraulic network in a building with a number of extraction points, comprising at least one pump unit and this regulating electronic control, wherein the control electronics is set up to carry out the inventive method.

The inventive method can be stored, for example in the form of a software-based settings assistant in the control electronics, which thus facilitates the adjustment of the pressure control curve at the pressure booster.

Further features and advantages of the method according to the invention are described below with reference to an embodiment and the accompanying figures.

Fig. 1:

HQ einer Druckerhöhungsanlage mit optimaler Druckregelkurve

Fig. 2:

erweitertes HQ Diagramm

Fig. 3:

HQ-Diagramm mit Trendfunktionen

Show it:

Fig. 1:

HQ of a pressure booster with optimal pressure control curve

Fig. 2:

extended HQ diagram

3:

HQ diagram with trend functions

• ein Volumenstromwert Q_100% eines gewünschten Maximalvolumenstroms auf der Druckregelkurve 1,
• einen Höhenwert H_geo einer geodätischen Höhe und
• einen Fließdruckwert p_FL eines gewünschten Fließdrucks an der ungünstigsten Entnahmestelle.

Fig. 1 shows an HQ diagram with two maximum pump curves 2, 3 for a pressure booster with exemplary two parallel operable pump sets. The outer maximum pump curve 3 is in common operation of both pump units at maximum speed. The nominal point of the pressure booster H _set , Q _set lies on the outer pump curve 3. An optimally controlled pressure booster has a proportional pressure control curve 1, which passes through this nominal point H _set , Q _set and the head difference H _set - H _{Q = 0} along the control curve just the maximum occurring pressure losses Δp _{loss, max} corresponds. To find and adjust this control curve 1, the Control electronics of the pressure booster according to the invention predetermined three system values:

• a volume flow value Q _{100% of} a desired maximum volume flow on the pressure control curve 1,
• an altitude value H _{geo of} a geodetic altitude and
• a flow pressure value p _{FL of} a desired flow pressure at the most unfavorable sampling point.

The maximum volume flow is the maximum volume flow on the pressure control curve. In practice, the volume flow can go beyond this, the pressure control curve then goes over into a plateau, wherein a constant pressure is predetermined and the maximum pump curve forms the limit.

Since the pressure booster knows itself, or the manufacturer of the pressure booster has knowledge about their pump characteristics, the volume flow value Q _100% manufacturer can be specified by the manufacturer as the volume flow value corresponding to the volume flow Q _set at the nominal operating point. The user then only needs to confirm this proposed default value on the control electronics. For example, the maximum volume flow Q is _100% = 8.3 m ³ / h.

The flow pressure is the static overpressure of a flowing medium, which must be present at the most unfavorable sampling point in a tapping process, so that the required amount of water can flow out. Also in the case of the flow pressure, it is possible to use a default value which is proposed to the user, since at a removal point usually at least 1 bar, preferably 2 bar flow pressure p _FL, should be applied in order to obtain an adequate flow. Again, the user only needs to confirm this proposed default value to the control electronics.

Thus, the user only has to specify the geodetic altitude value. The geodetic height here corresponds to the difference in height between the pressure booster and the highest extraction point and can thus be easily determined by the user. For example, the geodesic height is 24m.

From the three system values, the control electronics determines a minimum pressure p _{Q = 0} at zero flow rate and a maximum pressure p _Q100% at the predetermined maximum flow rate Q _100% , which in Fig. 2 are drawn. The minimum pressure p _{Q = 0} results from a mere conversion of the geodetic height value H _geo into a pressure value and addition of the flow pressure value p _FL. The numerical values given by way of example result in a minimum pressure po = o of 4.35 bar (H _geo / 10, 21 + p _FL ). The maximum pressure p _Q100% results from a mere conversion of the geodetic altitude value H _geo into a pressure value, addition of the flow pressure value p _FL and addition of a maximum pressure _loss Δp _{loss, max} . The numerical values given by way of example result in a maximum pressure p _Q100% of 5.15 bar (H _geo / 10.21 + p _FL + Δp _{loss, max} ).

The pressure control curve 1 to be determined is formed by a connecting line between the minimum pressure p _{Q = 0} and the maximum pressure p _Q100% and is set by the control _electronics according to their determination.

The calculation of the maximum pressure _loss Δp _{loss, max} is based on Fig. 3 illustrated. This shows purely by way of example five trend functions T1 to T5, which describe the dependence of the maximum pressure _loss Δp _{loss, max} on the volume flow in each case according to a root function. The trend functions T1 to T5 differ here only in their slope, which is described by a design factor k _A. The slope of the trend function depends on the hydraulic network of the building, which operates the pressure booster, for example on the pipe diameter.

In order to calculate the maximum pressure loss, a representative, mean trend function T3 can be used without differentiation between the individual trend functions T1 to T5, which, for example, is assigned the design factor k _A = 1. This results in the mean trend function T3 in Fig. 3 for a maximum volume flow Q _100% = 8.3 m ³ / h a maximum pressure _loss Δp _{loss, max} of 0.8 bar.

The trend functions T1, T2, T4 and T5 are empirically determined on the basis of the pipe sizing of hydraulic systems according to various design standards 1, 2, 3 and 4 and generally known pressure loss calculation according to the literature. As a design standard, for example, the DIN 1988 can be used, which describes the technical rules for new drinking water installations and indicates the associated, correct selection of the pipe diameter. This design standard has been amended several times over the past decades and the pipe diameters specified therein have been adapted, so that during the validity of a specific design standard, a specific pipe diameter was also valid. Due to the empirical determination of a particular trend function from one or more specific pipe diameters, any design standard for pipe diameters is assigned a specific trend function that can be used to calculate the maximum pressure loss. In addition to the DIN 1988 and its various versions, for example, the DIN EN 806 can be used.

Thus, a suitable trend function can be determined over the building age in order to determine the maximum pressure losses more accurately than by means of the representative mean trend function T3.

It can thus be provided that the control electronics expected an input of the building age. Accordingly, the building age can be specified by the user. The control electronics then selects one of the trend functions according to the entered building age. For this purpose, all trend functions can be stored in the control electronics, for example in the form of a value table or in the form of a mathematical function. In order to minimize the memory requirement, the design factor k _A can be used, with each building age being assigned a design factor k _A and selected by the user after the building age has been entered. Then only one trend function, for example the mean trend function T3, has to be stored in the control electronics, which is then simply multiplied by the design factor k _A.

Studies have shown that the trend function in drinking water installations with a comparatively high geodetic height should be steeper than in drinking water installations with a lower geodetic height. For this reason, in order to improve the accuracy in determining the maximum pressure losses, it is advantageous to make the slope of the trend function _geo- dependent depending on the geodetic height H. For this purpose, a height factor k _E to be multiplied by the trend function can be taken into account, which is the greater, the higher the geodetic height is. Below a limit value of, for example, 40 m, this height factor may for example be 1, increase linearly above the limit value, for example be 2 at 125 m, so that the slope is doubled.

Claims (15)

A method for setting a proportional pressure control curve (1) in the control electronics of a pressure booster for supplying a hydraulic network in a building with a number of withdrawal points, characterized in that the control electronics already from three assets, which a volume flow value (Q _100% ) of a desired maximum volume flow on the pressure control curve (1), - a height value (H _geo ) of a geodetic altitude and comprise a flow pressure value (p _FL ) of a desired flow pressure at the most unfavorable sampling point, a minimum pressure (p _{Q = 0} ) at zero flow and a maximum pressure (p _Q100% ) determined at the maximum flow, wherein the pressure control _curve (1) by a connecting line between the minimum pressure (p _{Q = 0} ) and the maximum pressure (p _Q100% ) is formed and adjusted by the control electronics. A method according to claim 1, characterized in that the volume flow value (Q _100% ) forms a factory set default value, the confirmation or change expected the control electronics. A method according to claim 2, characterized in that the default value corresponds to the volume flow at maximum hydraulic power of the pressure booster. A method according to claim 1, 2 or 3, characterized in that the volume flow value (Q _100% ) forms a predeterminable by a user input value, the input of the control electronics expected. Method according to one of the preceding claims, characterized in that the height value (H _geo ) forms an input value to be preset directly by a user whose input the control electronics expect. Method according to one of claims 1 to 4, characterized in that the height value (H _geo ) is determined from a predetermined by a user building height, the input of the control electronics expected. Method according to one of claims 1 to 4, characterized in that the height value (H _geo ) is determined from a predetermined number of floors by a user, in particular from a number of floors and a floor level, the input of the control electronics expected. Method according to one of the preceding claims, characterized in that the pressure value (p _FL ) forms a factory-set default value, preferably 3bar, whose confirmation or change the control electronics expects. Method according to one of the preceding claims, characterized in that the pressure value (p _FL ) forms a presettable by a user input value, the input of the control electronics expected. Method according to one of the preceding claims, characterized in that a geodetic pressure value (p _geo ) is calculated from the height value (H _geo ), and the minimum pressure (p _{Q = 0} ) is calculated from the sum of this geodetic pressure unit (p _geo ) and the flow pressure value ( p _FL ) is formed. Method according to one of the preceding claims, characterized in that from the volume flow value (Q _100% ) based on a trend function (T1-T5) calculates a maximum pressure _loss (Δp _{loss, max} ), and the maximum pressure (p _Q100% ) from the sum of the minimum pressure (p _{Q = 0} ) and the maximum pressure loss is formed. A method according to claim 11, characterized in that the trend function (T1-T5) describes the dependence of the maximum pressure _loss (Δp _{loss, max} ) on the volume flow (Q) according to a root function whose slope is defined by a selectable design factor (k _A ). A method according to claim 12, characterized in that by default a predefined mean value of the design factor (k _A ) is used. A method according to claim 12 or 13, characterized in that the control electronics expects the specification of a building age of the building, and selects the design factor (k _A ) from a number of stored design factors based on the user entered building age. Pressure booster system for supplying a hydraulic network in a building with a number of withdrawal points, comprising at least one pump unit and this regulatory control electronics, characterized in that the control electronics is adapted to carry out the method according to one of claims 1 to 14.

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