METHOD AND SYSTEM FOR SUPERVISING ELECTRICAL CONSUMPTION

Abstract

The invention relates to a method for monitoring the electrical consumption of a battery-powered communicating meter (1), comprising a measurement (101) of the electrical current consumed by said meter (1), characterized in that it comprises: identifying at least one functionality implemented by the meter by comparing (104) data relating to this measurement with signatures stored in a signature database (10), each signature in said database being representative of the meter's consumption during the implementation of a functionality by said meter (1) in a nominal operating mode of the meter (1); monitoring over time of the sequence of functionalities thus identified and detecting any drift from nominal operation. Figure for the abstract: Figure 3

Description

Title of the invention: METHOD AND SYSTEM FOR MONITORING ELECTRICITY CONSUMPTION FIELD OF THE INVENTION

[0001] The invention relates to a method and a system for monitoring the electrical consumption of a battery-powered communicating meter. More specifically, the invention finds application in the field of fluid meters (water meters, gas meters, etc.). STATE OF THE ART

[0002] Communicating meters allow consumption data (water, gas, etc.) to be monitored over time and this data to be transmitted, possibly in real time, to a remote distribution network manager. Different functionalities are managed by the meter's microprocessor(s) (measurement, transmission and reception of data, calculations, display, etc.). All of the meter's functionalities generate electrical consumption, as well as an associated current intensity value, which can vary over time. In a battery-operated communicating system, with a lifespan that can extend over several years, electrical consumption anomalies (overconsumption or underconsumption) can appear and have multiple causes, such as changes in the meter's environmental conditions (temperature, humidity, etc.); anomalies in the meter's application software, which may be difficult to detect; or premature wear of one or more electronic components of the meter.

[0003] These electrical consumption anomalies can have consequences on the battery life. It is therefore desirable to be able to monitor the electrical consumption of the meter and to detect and alert of any drift or inconsistency in operation compared to a nominal mode.

[0004] More generally, it is desirable to be able to monitor the proper functioning of the embedded software throughout the lifetime of the meter. Statement of the invention

[0005] A general aim of the invention is to propose a solution making it possible to overcome the drawbacks of communicating meters of the state of the art.

[0006] To this end, a method is provided for monitoring the electrical consumption of a communicating battery-powered meter, comprising a measurement relating to the electrical current consumed by said meter,

[0007] The method comprising: - an identification of at least one functionality implemented by the meter by comparison of data relating to this measurement measured with signatures stored in a signature database, each signature of said database being representative of the consumption of the meter during the implementation of a functionality by said meter in a nominal operating mode of the meter; - monitoring over time of the sequence of functionalities thus identified and the detection of any possible deviation from nominal operation.

[0008] Thus, the supervision method according to the invention makes it possible to identify sources responsible for the anomaly in electrical consumption of the communicating meter observed in relation to a normal operating mode, in particular the functionalities of the meter.

[0009] The method also makes it possible to monitor, continuously or intermittently, the electric current consumed by the various microcontrollers, radio modules and other elements which make up the constrained system.

[0010] The method also makes it possible to identify and monitor the actions taken by software embedded in the meter.

[0011] The method also makes it possible to estimate the remaining life of the battery following an anomaly observed in the electrical consumption of the meter.

[0012] Finally, the method makes it possible to alert a user of any abnormal consumption detected by a supervision system.

[0013] According to one implementation of the method, the detection of a drift generates the emission of an alert signal and / or corrective actions.

[0014] According to an implementation of the method, a corrective action comprises the identification of the functionality(s) responsible for a drift and a stopping of the functionality(s) or a reduction of a maximum current intensity allocated to this functionality(s).

[0015] According to one implementation of the method, at least one given functionality is maintained even in the event of drift, so as to guarantee that the meter remains in operation.

[0016] According to an implementation of the method, further comprising an estimation of a remaining life of the battery based on the measured data.

[0017] According to an implementation of the method, the functionalities of the communicating meter comprising one or more functionalities chosen from:

[0018] - radio transmissions

[0019] - operations performed by a microcontroller

[0020] - metrology operations

[0021] - low energy Bluetooth transmissions.

[0022] According to one implementation of the method, the method further comprises a detection of an electrical overconsumption and / or an electrical underconsumption by the communicating meter.

[0023] The invention further relates to a computer program product implementing the supervision method according to the invention.

[0024] The invention further relates to a system for monitoring the electrical consumption of a communicating meter, the monitoring system operating using application software separate from application software of the meter, the monitoring system comprising a microprocessor adapted to implement the method according to the invention.

[0025] Finally, the invention relates to a communicating battery-powered meter, comprising a supervision system according to the invention. DESCRIPTION OF FIGURES

[0026] We will now present an embodiment of the invention by way of non-limiting example with the support of the drawings in which:

[0027] [Fig.l] schematically illustrates a communicating meter, comprising a supervision system according to the invention.

[0028] [Fig.2] illustrates several signatures that can be included in the database data.

[0029] [Fig.3] is a functional diagram of the supervision method proposed by the invention, in its most general implementation.

[0030] [Fig.4] is a functional diagram illustrating the detection of signatures in the framework of the proposed process.

[0031] [Fig.5] is a functional diagram illustrating a particular implementation of the supervision process.

[0032] [Fig.6] is a functional diagram illustrating a dynamic process establishing a signature database. DETAILED DESCRIPTION

[0033] [Fig.l] represents a communicating meter 1. Such a meter typically comprises a microprocessor 2, a battery 3 and means of communication 4 with a remote server. It may in particular be a water or gas meter. This meter 1 is associated with a plurality of functionalities which together generate an overall electrical consumption of the meter. For example, for an electric meter, the functionalities may be the emission of a radio signal, the carrying out of measurements or the operation of a microcontroller.

[0034] The method can in particular be implemented by a supervision system 20 of the meter 1, the application system of which is distinct from an application system of the meter 1.

[0035] When each functionality is in normal operating mode, it consumes a certain current intensity value that can be characterized by a signature, generally by a maximum value and an average value, and possibly a minimum value. The signature can also include other data, such as the frequency or duration of the signal: for example, and with reference to [Fig. 2], a radio transmission is identifiable by an intensity of the order of ten milliamps over a duration ranging from ten milliseconds to ten seconds, while measurements are identifiable by short but regular current peaks. A drift in the consumed current intensity value, i.e. an overconsumption or underconsumption of current compared to the expected nominal value, generally indicates that a functionality is not in its normal operating mode.For example, this could be an anomaly in the software controlling the functionality, overheating, or wear and tear on certain electronic components that the functionality contains. Any consumption whose signature is not recognized and which adds a constant intensity level over long periods is considered a problem affecting battery 3 of the communicating meter 1.

[0036] The proposed method is implemented using a database to identify one or more features among the features of the meter 1 that are responsible for such a current anomaly. In its most general implementation, and with reference to [Fig. 3], the method comprises a first step 101 of measuring data relating to the electrical consumption of the meter 1. This data will generally include the current intensity value consumed by the meter, but may include other related values, such as the energy or power consumed by a feature, or the variation in intensity between two instants. It is thus possible to define an initial instant t0 and a final instant tj of the measurement 101, and a measurement step At between two successive measurement instants.The method then comprises a step 104 of comparing the measured data with signatures included in the database, which then allows a step 105 of identifying one or more signatures corresponding to functionalities responsible for the current anomaly.

[0037] [Fig.4] illustrates signature detection sub-steps of step 104 of com parison according to the proposed method. We begin by defining a maximum threshold Smax. Step 101 of measuring data relating to the current, in particular intensity measurements carried out at a plurality of times, is followed at each time by a step 302 of comparison between each measured intensity value and this threshold. The threshold Sm^ is chosen to be indicative of excess current consumption when the overall consumption of the meter 1 exceeds this threshold. As soon as a measured intensity value exceeds the threshold Smax, a recording 303 is initiated in step 3031 to record, for example in a memory of the supervision system 20, certain data chosen from the measured data. It is possible to choose to record all the data measured during the measurement step 301, or only some of these data considered to be more important, so as not to overload the memory of the supervision system 20. Advantageously, the recording 303 will include the recording of a maximum level of consumed intensity Imax, an average level of consumed intensity lavg and a minimum level of consumed intensity lmin over the total recording duration. The recording thus obtained can then be the subject of a comparison 304 with the signatures contained in the database. The comparison 304 can possibly be followed by a notification of the results of the comparison 304 to the controller 23 of the supervision system 20.We will then carry out the identification 105 of the functionalities 5 responsible for the anomaly in the electrical consumption of the communicating meter 1.

[0038] Recording is terminated in a step 3032 as soon as a measured intensity value is lower than the threshold Smax, which indicates a return to a normal operating mode.

[0039] Optionally, the method may only initiate the recording when a plurality of measured intensity values ​​exceed the threshold Smax, and / or only stop the recording 303 when a plurality of measured intensity values ​​are below the maximum threshold Smax. By a plurality of values, we mean either a predetermined number of measured values, or several values ​​measured during a predetermined period of time. This avoids an untimely start and / or stop of the recording 303 due to aberrant measured values, not representative of the signal that we are seeking to identify.

[0040] It is also possible, in a similar manner, to define a minimum threshold Smin indicative of an overall under-consumption of current of the meter 1, either in place of the maximum threshold Smax, or in addition to it.

[0041] According to a particular implementation, it is also possible to define a noise threshold Sh, corresponding to a current intensity value below which a measured value is not considered by the method as being indicative of a physical phenomenon. In other words, the method will not provide for any action on the basis of this measured value, even if it is lower than the minimum threshold Smin defined previously. This makes it possible to discard measurements which correspond to background noise and not to a real physical signal due to a functionality 5 of the communicating meter 1.

[0042] For the sub-steps of the comparison 104, the supervision system 20 defines a sliding window, the size and resolution of which will depend on the characteristics of the system, including its computing capacity, its RAM memory capacity, and / or the maximum size of the signatures it can contain. For example, Table 1 illustrates the identification of an intensity level signature used by the meter, carried out according to a plurality of instants. The threshold Smax is set at 12 microamperes, so that a signature is identified between instants t15 and t7. stars! t < -is f _, , f _ s ?1 f-ù î- 7 s il; ¢0 •w 'yj 1 If w 16 158G 1202 1§03 1258 48: S — 10 11 12

[0043] The functionalities of the communicating meter 1 may include, for example but not limited to, radio transmissions, operations carried out by one or more microcontrollers, metrology operations and / or low energy Bluetooth transmissions (in English “Bluetooth low energy” or BLE).

[0044] The method may further comprise detecting a drift of the measured data relative to an expected nominal operation of the meter.

[0045] According to one embodiment, the meter 1 comprises an interface 23 between the supervision system 20 and the rest of the meter 1, provided for exchanging data between them. When the comparison 104 has enabled the identification 105 of one or more signatures of functionalities of the meter 1 in the consumed intensity value, the recorded data can thus be sent during a sending step 106 to the supervision system 20 so as to enable their post-processing. When no identification 105 of signatures of functionalities of the meter 1 included in the database is obtained, the sending step 106 will be accompanied by a notification, so as to alert the supervision system 20 that an anomaly is occurring in the electrical consumption of the meter 1.Optionally, it may be provided that the sending step 106 comprises the sending of a notification when one or more signatures are identified but the consumption is not nominal compared to the values ​​recorded in the database, and in particular when under-consumption or over-consumption occurs. For example, the database may comprise signatures indicating a nominal intensity consumed as well as a range of intensity values ​​corresponding to the signature. If the recorded data comprise intensity values ​​which diverge from the nominal intensity but are within the range of values ​​thus defined, then the signature is identified but is considered to be non-nominal, and the sending step 106 then comprises a notification to the supervision system 20.A non-nominal signal but corresponding to a known signature will therefore typically have a period comparable to that of the corresponding nominal signal, with a change in the average intensity. Thus, any observation of a drift in the measured data compared to operation. The expected nominal value of the meter is notified to the supervision system, in order to alert it.

[0046] [Fig. 5] illustrates a particular implementation of the proposed supervision method. This implementation comprises the implementation of corrections 107 aimed at restoring normal operation of the meter 1, in particular to moderate the reduction in the remaining life of the battery during current overconsumption. Such corrections 107 may comprise a restriction of the functionalities identified as responsible for a current anomaly, in particular a threshold exceedance. It may be advantageous to implement these restrictions only when an anomaly is observed recurrently, as established following the observation, in the comparison step 104, of a drift in consumption compared to a nominal consumption and in the step 106 of sending data to the supervision system 20 via the interface 23.According to predefined criteria, such as a remaining capacity of the energy source of the meter 1, or the essential nature of the functionalities responsible for the current anomaly, the restriction 107 may consist of the total shutdown of the responsible functionalities, or more moderately in a restriction of the current intensity that they can receive from the energy source for their operation. Additionally or alternatively, certain functionalities may be defined as essential functionalities, for which it is necessary to allocate a certain current intensity value. If some of these essential functionalities are part of the functionalities responsible for a current anomaly, the restriction 107 may reduce the current allocated to these essential functionalities, but only so as to allow them to operate satisfactorily.On the other hand, if some of the functions responsible for an anomaly are not part of the essential functions, the current allocated to them may be reduced further, because a degradation of their operation, or even a total shutdown of the latter, is considered admissible. In the event of overconsumption, the current can thus be managed in order to prioritize the functions considered essential.

[0047] The corrections 107 can be implemented by a modification, possibly automated, of the configuration of application software of the communicating meter 1.

[0048] The supervision method may further comprise a calculation 108 of the remaining energy level Crestant in the battery 3 of the meter 1 following the detection of a current anomaly. This energy level is calculated according to the equation:

[0049] Crestante( t) remainder {t-\} ~ idle) ~ sig '" ^sig)

[0050] where At is the step between two detected signatures, Asig the duration of the detected signature, Z^ the average nominal consumption of meter 1 and lsig the intensity average of the detected signature, and t and ll represent respectively instants after and before the current anomaly. This calculation of the remaining energy level will eventually make it possible to estimate the remaining life of battery 3.

[0051] The invention also proposes a computer program product implementing the supervision method described above.

[0052] As mentioned previously, the communicating meter 1 according to the invention comprises a supervision system 20 making it possible to implement the proposed method. This system 20 operates using application software distinct from that of the meter 1. It comprises at least one microprocessor 22, which may be distinct from a microprocessor of the meter 1, or operate using the same multi-core processor as the meter 1 using a core distinct from that used by the meter 1. Alternatively, the meter 1 and the supervision system 20 may operate using the same microprocessor 22 implementing two distinct application software programs. The supervision system 2 comprises at least one detection element 21 capable of detecting the current flow. This may in particular be a low-value resistor, of the order of a milliohm, placed in the current path. The value of the current is deduced from the voltage across the terminals of the meter 1 using Ohm's law.

[0053] The fact of providing a supervision system 20 operating using application software different from application software of the meter 1 makes it possible to avoid the transmission of a bug appearing in one of these two software programs to the second.

[0054] The database comprising the signatures used by the proposed supervision method can be established by a static method or a dynamic method. Table 2 illustrates examples of functionalities, with the associated minimum, average and maximum intensity, the duration of the signal and the period, if applicable. Functionality Intensity Duration Period (if synchronous) Minimum Average Maximum Metrology 2 uA 5 uA 10 uA 10 ms 125 ms Radio 10 mA 60 mA 120 mA 200 ms 1 per day Button 1 mA 12 mA 1.6 mA 200 ms - LCD 235 uA 250 uA 255 uA 60 sec - BLE 5 mA 6 mA 7 mA 20 sec External flash 1.5 mA 1.6 mA 1.7mA 20 sec 1 per day

[0055] The static method consists of injecting a reference database 10 into the embedded software of the meter 1, this database being established prior to the assembly of the meter, for example by laboratory measurements.

[0056] With reference to [Fig.6], the dynamic method consists of establishing the database during the operation of the counter. This dynamic method must be done in mode of nominal operation of the meter, that is to say when it is established that no anomaly of current consumed is taking place. A functionality of the meter whose signature is to be obtained is started according to a step 201. Then, a recording 202 of data relating to the electric current consumed by the functionality is initiated, which will determine its signature - for example but not limited to, a minimum intensity value Imin, maximum lmax and / or average Iavg, a signal duration, or a frequency. When the signature is obtained, the recording is ended and the functionality is stopped in a stop step 203. This dynamic method has the advantage of allowing the addition of functionalities later in the manufacture of the meter 1, then the characterization of their signatures in order to be able to implement the proposed supervision method.This dynamic method can also be implemented for a given duration for a plurality of functionalities in order to establish a database for all these functionalities.

[0057] When supervision of the meter 1 is desired at any time during its operation, the supervision system 20 can implement the proposed method continuously. Alternatively, and in order to avoid the production of overconsumption by the supervision system 20 itself, it is possible to implement the method intermittently. A first alternative is to carry out measurements during a given period over a time range, for example but not limited to ten seconds every hour. A second alternative is to modulate the measurement step At. These two alternatives can possibly be combined by carrying out sampling of a given number of measurements during a given period over a time range.Another alternative, which can be carried out separately or in combination with the previous ones, is to synchronize the implementation of the supervision method with an event which is known to have an influence on the overall consumption of meter 1, such as the start of a radio signal transmission.

[0058] Intermittent operation of the supervision system 20 can make it possible to detect certain current anomalies, such as sporadic consumption drifts, or periodic overconsumption, while extending the lifespan of the energy source compared to continuous supervision.

[0059] According to a particular implementation, when it is desired to further limit the loss of life of the energy source associated with the use of the supervision system 20, it is possible to allocate a percentage of the capacity of the energy source, or a maximum current intensity to the supervision system 20. It is possible, for example, but not limited to, to allocate 5% of the total capacity of the battery 3 to the operation of the supervision system 20, and thus ensure that no drift or consumption anomaly does not go unnoticed.

[0060] Typically, the dimensioning of the supervision system 20 is carried out during the manufacture of the meter, so as to respect such a consumption limit with regard to the capacity of the battery. For example, but not limited to, it is possible to provide for allocating a current of one hundred microamps for a supervision system 20 operating continuously, or of twenty microamps per measurement for a supervision system carrying out discrete measurements.

Claims

Claims

1. Method for monitoring the electrical consumption of a communicating battery-powered meter (1), comprising a measurement (101) relating to the electrical current consumed by said meter (1), characterized in that it comprises: - an identification of at least one functionality implemented by the meter by comparison (104) of data relating to this measurement measured with signatures stored in a database (10) of signatures, each signature of said database being representative of the consumption of the meter during the implementation of a functionality by said meter (1) in a nominal operating mode of the meter (1); - a monitoring over time of the sequence of functionalities thus identified and the detection of a possible drift compared to a nominal operation, - an identification of at least one functionality implemented by the meter responsible for the drift.

2. Method according to claim 1, in which the detection of a drift generates the emission of an alert signal and / or corrective actions.

3. A method according to claim 2, wherein a corrective action (107) comprises a shutdown of the functionality(s) responsible for the drift or a reduction of a maximum current intensity allocated to this (or these) functionality(s).

4. Method according to one of claims 1 to 3, in which at least one given functionality is maintained even in the event of drift, so as to guarantee that the meter remains in operation.

5. Method according to one of claims 1 to 4, further comprising an estimation (108) of a remaining life of the battery (3) based on the measured data.

6. Method according to one of claims 1 to 5, the functionalities of the communicating meter comprising one or more functionalities chosen from: - radio transmissions - operations carried out by a microcontroller - metrology operations - low-energy Bluetooth transmissions

7. Method according to one of claims 1 to 6, further comprising a detection of an electrical overconsumption and / or an electrical underconsumption by the communicating meter (1).

8. Computer program product implementing the supervision method according to one of claims 1 to 7.

9. System (20) for supervising the electrical consumption of a communicating meter (1), the supervision system (20) operating using application software separate from application software of the meter (1), the supervision system (20) comprising a microprocessor (22) adapted to implement the method according to any one of claims 1 to 7.

10. Communicating meter (1) with battery, comprising a supervision system (2) according to the preceding claim.

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