Quality measurement assessed by a fluid meter

Abstract

Fluid meter (1) comprising: - a conduit (4) through which the fluid flows; - a transmitter (12) arranged to emit a light signal (S1) into the conduit; - a receiver (14) arranged to receive the light signal after it has traveled a predefined path in the conduit; - a processing unit (5) arranged to acquire an electrical signal (Se) produced by the receiver, and to evaluate the turbidity of the fluid from said electrical signal. ABBREVIATED FIGURE: Fig. 1

Description

Title of the invention: Qualimetry evaluated by a fluid meter

[0001] The invention relates to the field of communicating fluid meters.

[0002] BACKGROUND OF THE INVENTION

[0003] The distribution of drinking water is ensured by distribution networks which include pipes and hydraulic devices which make it possible to optimize the circulation of water from water reservoirs to the installations of end users via the pipes.

[0004] For health safety reasons, it is essential to control the quality of drinking water.

[0005] The quality of the water distributed depends of course on the quality of the water at the time of its collection, the treatments it undergoes, but also on the materials with which it is in contact in the reservoirs and during its circulation in the distribution network. Deposition phenomena (biofilms, scaling, metal oxides, etc.) can in fact occur in the reservoirs and pipes.

[0006] Water producers, network managers and health authorities therefore monitor the quality of the drinking water distributed very closely and constantly.

[0007] This monitoring may, however, lack precision due in particular to the extent of the distribution networks. For example, it is possible that the water quality observed at end users located in a particular area is significantly lower than the quality assessed upstream of said area. This may result from localized degradation of the pipes, which the monitoring devices are not capable of detecting.

[0008] It therefore seems relevant to try to improve the accuracy of the assessment of the quality of the water supply depending on the location in the network. It would be preferable if the cost associated with this improvement were not too high.

[0009] SUBJECT OF THE INVENTION

[0010] The subject of the invention is a solution making it possible, in a fluid distribution network, to improve the precision of the evaluation of the quality of the supply of the fluid as a function of the location, said solution having a limited cost. Summary of the invention

[0011] In order to achieve this goal, a fluid meter is proposed comprising:

[0012] - a conduit in which the fluid circulates;

[0013] - a transmitter arranged to emit a light signal into the conduit;

[0014] - a receiver arranged to receive the light signal after it has traveled a predefined path in the conduit;

[0015] - a processing unit arranged to acquire an electrical signal produced by the receiver, and to evaluate a turbidity of the fluid from said electrical signal.

[0016] The transmitter and receiver of the light signal are therefore used to evaluate the turbidity of the fluid circulating in the meter conduit.

[0017] Turbidity is a relevant parameter for measuring the quality of the fluid supply. The assessment of turbidity is carried out by the meter itself and therefore at the level of the end user's installation. The invention therefore makes it possible to obtain a measurement of the quality of the fluid supply, which is associated with a very precise location in the network.

[0018] The cost of turbidity assessment is very low, because the transmitter and receiver of the light signal are inexpensive components that are easy to integrate into the meter.

[0019] A fluid meter is further provided as previously described, in which the fluid flows in the conduit in a first direction, and in which the predefined path extends in a second direction perpendicular to the first direction.

[0020] A fluid meter as previously described is further provided, in which the light signal is an infrared signal.

[0021] A fluid meter as previously described is further provided, in which the transmitter is a light-emitting diode and the receiver is a photodiode.

[0022] There is further provided a fluid meter as previously described, in which the conduit comprises two holes, and in which the transmitter and the receiver each extend at least partially through one of the holes.

[0023] A fluid meter as previously described is further provided, wherein the two holes are located on the conduit at diametrically opposite positions.

[0024] We further propose a fluid meter as previously described, in which the electrical signal is an electrical current, and in which the turbidity evaluated by the processing unit is inversely proportional to said electrical current.

[0025] A fluid meter is further proposed as previously described, further comprising an ultrasonic measuring device comprising an upstream transducer and a downstream transducer and arranged to measure a flow rate of the fluid, the transmitter and the receiver being positioned downstream of the upstream transducer and the downstream transducer.

[0026] A fluid meter is further provided as previously described, the processing unit being arranged to evaluate quality parameters representative of a quality of a supply of the fluid, said quality parameters comprising the turbidity of the fluid.

[0027] A fluid meter is further provided as previously described, the quality measurement parameters further comprising a temperature of the fluid.

[0028] A fluid meter as previously described is further provided, the processing unit being arranged to evaluate a speed of sound in the fluid using the ultrasonic measuring device, then to evaluate the temperature of the fluid from the speed of sound.

[0029] A fluid meter is further proposed as previously described, in which the meter comprises at least one pressure sensor, the quality measurement parameters further comprising a pressure measured by said pressure sensor.

[0030] A fluid meter is further proposed as previously described, in which the meter comprises an upstream pressure sensor, positioned on one side of an upstream end of the conduit, and a downstream pressure sensor, positioned on one side of a downstream end of the conduit, the quality measurement parameters further comprising a pressure value representative of a pressure difference between an upstream pressure measured by the upstream pressure sensor and a downstream pressure measured by the downstream pressure sensor.

[0031] A fluid meter as previously described is further proposed, further comprising a communication module, the processing unit being arranged to receive via the communication module a request sent by a system external to the fluid meter, and to, in response to said request, transmit the quality measurement parameters to said system.

[0032] A measuring method is further proposed, implemented in the processing unit of a fluid meter as previously described, comprising the steps of:

[0033] - control the transmitter so that it emits the light signal into the conduit;

[0034] - acquire the electrical signal produced by the receiver;

[0035] - assessing a turbidity of the fluid from said electrical signal.

[0036] A computer program is further provided comprising instructions which cause the processing unit of the fluid meter as previously described to execute the steps of the measuring method as previously described.

[0037] A computer-readable recording medium is further provided, on which the computer program as previously described is recorded.

[0038] The invention will be better understood in light of the following description of a particular non-limiting embodiment of the invention. Brief description of the drawings

[0039] Reference will be made to the attached drawings, among which:

[0040] [Fig-1] [Fig.l] represents a water meter;

[0041] [Fig.2] [Fig.2] represents a simplified and partial sectional view of the conduit of the meter, according to a plane passing through a longitudinal axis of the conduit. DETAILED DESCRIPTION OF THE INVENTION

[0042] With reference to [Fig.l], the water meter 1 is used to measure the water consumption of the installation 2 of an end user. The water is supplied to installation 2 by a water distribution network 3.

[0043] The meter 1 comprises a conduit 4 in which the water supplied by the network 3 to the installation 2 circulates. The water circulates in the conduit 4 from upstream to downstream, as indicated by the direction of the arrows F. Here, by "upstream" is meant on the side of the network 3, and by "downstream" is meant on the side of the installation 2.

[0044] The counter 1 comprises a processing unit 5 (electronic and software). The processing unit 5 comprises at least one processing component 5a, which is for example a “generalist” processor, a processor specialized in signal processing (or DSP, for Digital Signal Processor), a microcontroller, or a programmable logic circuit such as an FPGA (for Field Programmable Gate Arrays) or an ASIC (for Application Specific Integrated Circuit).

[0045] The processing unit 5 also comprises one or more memories 5b, connected to or integrated in the processing component 5a. At least one of these memories 5b forms a computer-readable recording medium, on which is recorded at least one computer program comprising instructions which cause the processing component 5a to execute at least some of the steps of the measurement method which will be described below.

[0046] The processing component 5a is here the metrology microcontroller of the meter 1. The microcontroller 5a integrates an analog-digital converter (ADC) 6.

[0047] The meter 1 further comprises a communication module 7. The communication module 7 implements, for example, a cellular radio link according to the LTE-Cat M1 protocol or the NB-IoT protocol.

[0048] The meter 1 also comprises an ultrasonic measuring device 8. The ultrasonic measuring device 8 is used to measure the flow rate of water supplied to the installation 2 by the network 3.

[0049] The ultrasonic measuring device 8 comprises an upstream transducer 9a and a downstream transducer 9b. The ultrasonic measuring device 8 also comprises a calculation module 10 (software) which is implemented here in the microcontroller 5a of the processing unit 5. The calculation module 10 carries out the flow rate evaluations.

[0050] The upstream transducer 9a and the downstream transducer 9b are advantageously (but not necessarily) paired. The upstream transducer 9a and the downstream transducer 9b are here piezoelectric transducers.

[0051] Each transducer 9a, 9b successively plays the role of a transmitter and a receiver of ultrasonic signals.

[0052] The processing unit 5 generates an electrical excitation signal, and provides the transmitter with the electrical excitation signal. The transmitter then generates an ultrasonic signal. The receiver receives the ultrasonic signal after it has traveled a first predefined path in the water.

[0053] The first predefined path is here a direct path which is here inclined relative to a longitudinal axis XI of the conduit 4 (the first predefined path could also be parallel to said axis XI). The first predefined path could also be an indirect path: the ultrasonic signals would then be reflected against the internal wall of the conduit 4 (possibly against reflectors themselves located on the internal wall).

[0054] The first predefined path has a first length Ll, which is known very precisely.

[0055] The upstream transducer 9a and the downstream transducer 9b are in particular connected to the CAN 6 which digitizes the signals produced by said transducers.

[0056] Thus, the processing unit 5 first applies the electrical excitation signal to the terminals of the upstream transducer 9a so that the latter generates an upstream ultrasonic signal Sm in the conduit 4. The processing unit 5 acquires a downstream electrical signal produced by the downstream transducer 9b when the latter receives the upstream ultrasonic signal Sm.

[0057] Then, the processing unit 5 applies the electrical excitation signal to the terminals of the downstream transducer 9b so that the latter generates a downstream ultrasonic signal Sv in the conduit 4. The processing unit 5 acquires an upstream electrical signal produced by the upstream transducer 9a when the latter receives the downstream ultrasonic signal Sv.

[0058] The calculation module 10 analyzes the downstream electrical signal and the upstream electrical signal to evaluate a speed of the water in the conduit 4, then evaluates, from the speed of the water, the flow rate of the water in the conduit 4.

[0059] The meter 1 further comprises at least one pressure sensor, in this case two pressure sensors: an upstream pressure sensor 11a, which is positioned on the side of the upstream end of the conduit 4, and a downstream pressure sensor 11b, which is positioned on the side of the downstream end of the conduit 4.

[0060] The upstream pressure sensor 11a and the downstream pressure sensor 11b are connected to the processing unit 5. The upstream pressure sensor 11a and the downstream pressure sensor 11b are in particular connected to the CAN 6 which digitizes the measurements produced by said sensors.

[0061] The meter 1 further comprises a transmitter 12 arranged to emit a light signal SI in the conduit 4, and a receiver 14 arranged to receive the light signal SI after it has traveled a second predefined path in the conduit 4 (and therefore in the water).

[0062] The second predefined path extends in a second direction X2 perpendicular to a first direction (axis XI) in which the water circulates.

[0063] The second predefined path has a second length L2, which is known very precisely.

[0064] The light signal SI is here an infrared signal. The wavelength of the signal luminous SI is for example equal to 860nm.

[0065] The transmitter 12 is here a light-emitting diode (LED) and the receiver 14 is a photodiode.

[0066] With reference to [Fig.2], a first hole 15a and a second hole 15b, passing through, are formed in the thickness e of the wall of the conduit 4. The first hole 15a and the second hole 15b are located on the conduit 4 at diametrically opposite positions.

[0067] The LED 12 and the photodiode 14 each extend at least partially through one of the holes 15a, 15b.

[0068] The LED 12 is here encapsulated in a cylindrical-shaped housing with a rounded end. The rounded end here comprises a lens. The housing is transparent or translucent to infrared light. The housing is here made of epoxy resin.

[0069] The LED 12 is inserted into the first hole 15a so that the end of the LED 12, corresponding to the rounded tip, protrudes inside the conduit 4.

[0070] The seal is ensured by a first seal 16a which extends around the housing of the LED 12 while being positioned between the housing of the LED 12 and the wall of the conduit 4 at the level of the first hole 15a.

[0071] The photodiode 14 is also encapsulated in a cylindrical housing with a rounded end. The rounded end here comprises a lens.

[0072] The photodiode 14 is inserted into the second hole 15b opposite the LED 12 so that the end of the photodiode 14, corresponding to the rounded tip, projects inside the conduit 4. The seal is ensured by a second seal 16b which extends around the housing of the photodiode 14 while being positioned between the housing of the photodiode 14 and the wall of the conduit 4 at the level of the second hole 15b.

[0073] The LED 12 and the photodiode 14 are connected to the processing unit 5.

[0074] The processing unit 5 can activate the LED 12 so that it emits the light signal SI, and acquire the electrical signal Se produced by the photodiode 14 when the latter receives the light signal SI.

[0075] The photodiode 14 is connected to the CAN 6 of the microcontroller 5 which digitizes the electrical signal produced by the photodiode 14.

[0076] It is noted that the LED 12 and the photodiode 14 are here positioned downstream of the upstream transducer 9a and the downstream transducer 9b of the ultrasonic measuring device 8. This ensures that these components do not disturb the metrological measurement of the water flow rate carried out by the ultrasonic measuring device 8.

[0077] The processing unit 5 evaluates quality parameters representative of the quality of the water supply.

[0078] The quality parameters firstly include the turbidity of the water.

[0079] The processing unit 5 therefore controls the LED 12 so that it emits the signal

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[0093] light SI in the conduit 4, and acquires the electrical signal Se produced by the photodiode 14. The processing unit 5 is therefore capable of determining the quantity of light received by the photodiode 14. The processing unit 5 evaluates the turbidity of the water from said electrical signal Se. The electrical signal Se is an electric current. The turbidity evaluated by the processing unit 5 is inversely proportional to said electric current. Turbidity is expressed in NTU (for Nephelometric Turbidity Unit), which is a unit that represents an order of magnitude in mg / L of MES (Suspended Matter). A calibration of the system including the LED 12 and the photodiode 14 integrated in the counter 1, is carried out in the factory. Current measurements are, for example, carried out at a frequency of one measurement per second. To carry out a turbidity measurement at time T, the processing unit 5 here carries out a predetermined number of measurements of the electrical signal produced by the photodiode 14 (the LED 12 being activated). The predetermined number is for example equal to 10, i.e. for example 5 measurements before time T and 5 measurements after time T. The processing unit 5 calculates the average of these 10 current measurements to obtain an averaged current value. The processing unit 5 then produces a turbidity measurement from the averaged current value. The quality parameters also include water temperature. The processing unit 5 evaluates a sound speed (or sound celerity) in the water using the ultrasonic measuring device 8, and then evaluates the water temperature from the sound speed. The ultrasonic measuring device 8 makes it possible to measure the speed c of sound, in the following manner. The calculation module 10 first determines the sum of the flight times (ToF) of the ultrasonic signals between the two transducers 9a, 9b: sTOF. The sum of the sTOF flight times is therefore equal to the sum: - the time taken by the upstream ultrasonic signal Sm to travel the first predefined path between the upstream transducer 9a and the downstream transducer 9b, and - the time taken by the downstream ultrasonic signal Sv to travel the first predefined path between the downstream transducer 9b and the upstream transducer 9a. The processing unit 5 then evaluates the speed of sound using the following formula: r- 2 x7.1 1 sTOF ' where El is the first length of the first predefined path. Then, processing unit 5 uses the following formula to evaluate the water temperature from the speed of sound: c = 1.40238677*10A3 + 5.03798765*7 - 5.80980033^0^(-2) 7*2+ 3.3429665O*IOA(-4) 7A3- 1.47936902« 10A(-6) 7*4 + 3.14893508* 10*(-9) 7*5

[0094] This equation admits a positive solution which corresponds to the water temperature T.

[0095] This way of evaluating the water temperature is very advantageous, since it does not require integrating a temperature sensor into the meter 1. The water temperature is evaluated using the transducers 9a, 9b which are present in the meter 1 to carry out the metrology measurements. The evaluation of a very relevant parameter for evaluating the quality of the water supply is therefore obtained without additional costs.

[0096] The quality measurement parameters further include a pressure measured by one of the pressure sensors of the processing unit 5.

[0097] This is the upstream pressure Pm measured by the upstream pressure sensor 11a.

[0098] The quality parameters must verify predefined conditions in the case of a water meter to comply with the expected supply quality. The predefined conditions are as follows: - upstream pressure Pm < 16 Bar; - Water temperature T: • Between 0.1°C and 30°C (for a cold water meter); • Between 50°C and 70°C (for a hot water meter); - Turbidity ^5 NT U.

[0099] The quality measurement parameters further comprise a pressure value representative of a pressure difference between an upstream pressure measured by the upstream pressure sensor 11a and a downstream pressure measured by the downstream pressure sensor 11b.

[0100] The pressure value here is equal to:

[0101] AP = P m -P v ,

[0102] where Pm is the upstream pressure and Py is the downstream pressure.

[0103] The pressure value AP is the pressure loss due to meter 1 itself. It does not This is therefore not strictly speaking a quality parameter, capable of assessing the quality of the water supply, but rather a constraint that meter 1 must respect in order to comply with its technical and functional specifications. The channeling of the flow in meter 1 necessarily results in a slight loss of load, but this must be limited.

[0104] The AP pressure drop must verify the following predefined condition:

[0105] dP<0.63 Bar.

[0106] The numerical values ​​used for the predefined conditions are programmable and can be modified according to regulatory requirements.

[0107] The processing unit 5 creates a daily table 17 which contains the quality measurement measurements produced periodically. The period is for example equal to a quarter of an hour (i.e. 96 measurements per day).

[0108] Table 17 is stored in one of the memories 5b. An example of Table 17 is provided in the appendix.

[0109] Table 17 therefore contains 96 lines of measurements taken every quarter of an hour (for example from 00:07:30” to 23:52:30”).

[0110] Each quarter of an hour (sample) is associated with measurements of upstream pressure, pressure drop, temperature and turbidity.

[0111] The processing unit 5 stores these values ​​here over a week (therefore seven daily tables 17, identical to that provided in the appendix, including the table for the current day).

[0112] The processing unit 5 can transmit this data to a system external to the meter 1 using the communication module 7. The processing unit 5 receives, for example, via the communication module 7, a request sent by said system. The processing unit 5, in response to said request, transmits the quality measurement parameters to the external system via the communication module 7.

[0113] The external system is, for example, the IS (for Information System) of the water distributor and / or the network manager.

[0114] The IS produces, for example, a dedicated DLMS request, to which counter 1 responds by sending table 17.

[0115] The meter 1 can also send an alarm message to the water distributor, the network manager, or even the end user, when the quality of the water supply is not satisfactory (i.e. it does not meet the predefined conditions mentioned earlier).

[0116] The assessment of the quality of the water supply by the meter provides legal proof that the quality of the supply to the end user is that expected in terms of water temperature, pressure and turbidity.

[0117] Finally, it should be noted that, with regard to the distribution of electricity, quality measurement is defined in the NF EN 61000-4-30 standard. There is currently no standard relating to fluid meters, and no one has had the idea of ​​defining the quality of supply in the case of water typically. However, it seems extremely relevant to do so. This is one of the aims of the present invention.

[0118] Of course, the invention is not limited to the embodiment described but encompasses any variant falling within the scope of the invention as defined by the claims.

[0119] The meter is not necessarily a water meter, it can be a meter for any fluid: gas, oil, etc.

[0120] The LED and the photodiode do not necessarily extend through holes formed in the thickness of the conduit. The LED and the photodiode could be positioned outside the conduit and opposite these holes, which would for example be closed by transparent or translucent surfaces (glass for example). The LED and the photodiode could also be fixed to the internal wall of the conduit, or else integrated into a measuring device itself integrated into the conduit.

[0121] The transmitter and receiver of the light signal are not necessarily an LED and a photodiode. It could be a laser diode and a phototransistor for example.

[0122] The light signal is not necessarily an infrared signal, it could belong to the visible range for example. Appendix

[0123] Measurement Types Samples J, Upstream Pressure (Bar) AP (Bar) Pressure Drop Temperature (°C) Turbidity (NTU) 1 XXX XXX yyy zzz 2 XXX XXX yyy zzz 3 XXX XXX yyy zzz 95 XXX XXX yyy zzz 96 XXX XXX yyy zzz

Claims

Claims

1. Fluid meter (1) comprising: - a conduit (4) in which the fluid circulates; - a transmitter (12) arranged to emit a light signal (SI) in the conduit; - a receiver (14) arranged to receive the light signal after it has traveled a predefined path in the conduit; - a processing unit (5) arranged to acquire an electrical signal (Se) produced by the receiver, and to evaluate a turbidity of the fluid from said electrical signal.

2. A fluid meter according to claim 1, wherein the fluid flows in the conduit in a first direction (XI), and wherein the predefined path extends in a second direction (X2) perpendicular to the first direction.

3. Fluid meter according to one of the preceding claims, in which the light signal (SI) is an infrared signal.

4. A fluid meter according to any preceding claim, wherein the transmitter is a light-emitting diode and the receiver is a photodiode.

5. A fluid meter according to any preceding claim, wherein the conduit comprises two holes (15a, 15b), and wherein the transmitter and receiver each extend at least partially through one of the holes.

6. A fluid meter according to claim 5, wherein the two holes (15a, 15b) are located on the conduit at diametrically opposite positions.

7. Fluid meter according to one of the preceding claims, in which the electrical signal (Se) is an electrical current, and in which the turbidity evaluated by the processing unit (5) is inversely proportional to said electrical current.

8. Fluid meter according to one of the preceding claims, further comprising an ultrasonic measuring device (8) comprising an upstream transducer (9a) and a downstream transducer (9b) and arranged to measure a flow rate of the fluid, the transmitter (12) and the receiver (14) being positioned downstream of the upstream transducer and the downstream transducer.

9. Fluid meter according to one of the preceding claims, the unit treatment (5) being arranged to evaluate quality parameters representative of a quality of a supply of the fluid, said quality parameters comprising the turbidity of the fluid.

10. A fluid meter according to claim 9, the quality parameters further comprising a temperature of the fluid.

11. A fluid meter according to claims 8 and 10, the processing unit (5) being arranged to evaluate a sound speed in the fluid using the ultrasonic measuring device (8), and then to evaluate the temperature of the fluid from the sound speed.

12. Fluid meter according to one of claims 9 to 11, in which the meter (1) comprises at least one pressure sensor (11a, 11b), the quality measurement parameters further comprising a pressure measured by said pressure sensor.

13. Fluid meter according to claim 12, wherein the meter (1) comprises an upstream pressure sensor (11a), positioned on one side of an upstream end of the conduit (4), and a downstream pressure sensor (11b), positioned on one side of a downstream end of the conduit, the quality measurement parameters further comprising a pressure value representative of a pressure difference between an upstream pressure measured by the upstream pressure sensor and a downstream pressure measured by the downstream pressure sensor.

14. Fluid meter according to one of claims 9 to 13, further comprising a communication module (7), the processing unit (5) being arranged to receive via the communication module a request sent by a system external to the fluid meter, and to, in response to said request, transmit the quality parameters to said system.

15. Measuring method, implemented in the processing unit (5) of a fluid meter (1) according to one of the preceding claims, comprising the steps of: - controlling the transmitter (12) so that it emits the light signal (SI) in the conduit (4); - acquiring the electrical signal (Se) produced by the receiver (14); - evaluating a turbidity of the fluid from said electrical signal.

16. Computer program comprising instructions which cause the processing unit (5) of the fluid meter (1) according to one of the preceding claims to execute the steps of the measuring method according to claim 15.

17. A computer-readable recording medium on which the computer program according to claim 16 is recorded.

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