FR2748326A1 - PRE-POWERED ENERGY MONITORING SYSTEM WITH ANTI-FRAUD DEVICE - Google Patents

Abstract

The system includes an energy management circuit with an anti-fraud device. The energy management circuit detects (F18) the existence of energy consumption after it is switched on. In the absence of such consumption, an anomaly is signaled (F19), intended to draw attention to the probability of a fraud consisting in short-circuiting the measurement circuit of the management circuit. The management circuit also checks (F23) for the possible existence of a negative energy credit balance (C). The existence of such a balance is signaled (F25) so as to draw attention to the probability of a fraud consisting in short-circuiting the system cut-off contacts which normally open under the control of the management circuit energy when the energy credit balance (C) is canceled.

Description

ENERGY MONITORING SYSTEM WITH A DEVICE

FRAUD

  The invention relates to a prepayment energy control system comprising energy management means comprising means for detecting fraud, said means

  fraud detection device comprising voltage presence signaling means.

  Prepaid energy control systems are known in which each user has a management circuit, with a power measurement circuit used, connected to a switch or a circuit breaker to interrupt the power supply to the power supply. user when the amount of a credit energy, stored in the management circuit and reduced as the energy consumption, is canceled. The amount of the credit can be modified by introducing into the management circuit a prepayment code. In known systems, this code is introduced either by means of a keyboard, or by means of a magnetic card, or by means of a chip support. In known systems, some measures have been taken to prevent fraud. It is in particular known to use mechanical anti-fraud devices, for example in the form of seals. Electronic anti-fraud devices meanwhile, have the disadvantage of not working in the absence of power, which can facilitate their bypass by an unscrupulous user. The known devices include in particular a voltage presence diode which is lit only when the management circuit is powered. The extinction of the voltage presence diode can therefore easily signal a fraud by short-circuiting the energy control system. By

  however, it is insufficient to detect other types of fraud.

  The purpose of the invention is to improve anti-fraud detection in a control system

prepaid energy.

  According to the invention this object is achieved by the fact that the fraud detection means comprise means for detecting the existence of a power consumption from the powering up of the energy management means, and signaling means

an anomaly in his absence.

  According to a development of the invention, the energy management means comprise input means and storage of an energy credit means for measuring the amount of energy consumed by a user, means determining an energy credit balance according to said energy credit and the quantity of energy consumed, the means for detecting fraud comprising means for detecting a negative energy credit balance and means of signaling a fraud when said

0 balance is negative.

  The means for detecting the existence of a power consumption comprise, from

  preferably, current measuring means.

  Thus, the energy management circuit detects the existence of a power consumption after powering up. In the absence of such consumption, an anomaly is

  reported, intended to draw attention to the likelihood of fraud consisting of short-term

  circuit the measuring circuit of the management circuit. The management circuit also checks for the existence of a negative energy credit balance. The existence of such a balance is

  reported in order to draw attention to the likelihood of fraud consisting of short-term

  circuit the system cutoff contacts.

  Other advantages and features will become more apparent from the following description

  of a particular embodiment of the invention given by way of non-limiting example and represented by the appended drawings in which: FIG. 1 represents a prepayment energy control system according to the prior art, in which The invention can be implemented. FIGS. 2 to 4 illustrate the different types of fraud that may be detected by a

anti-fraud device.

  FIGS. 5 and 6 illustrate particular embodiments of flowcharts of FIG.

  processing for the implementation of the invention in a system according to Figure 1.

  The pre-paid energy control system of FIG. 1 comprises a power management circuit 1 and a switch or circuit breaker 2. The switch 2 comprises contacts 3 interposed on supply lines LI and L2 intended to supply energy to a user. The opening of the contacts 3 is controlled by a relay 4 of

  the switch 2, under the control of the management circuit 1.

  The management circuit 1 comprises a measuring circuit 5 connected to a microprocessor processing circuit 6. The measuring circuit 5 may comprise current sensors, and possibly voltage sensors, arranged on the lines LI and L2, the circuit of FIG. treatment 6

  can then calculate the power delivered to the user and the energy consumed.

  Alternatively, the measuring circuit 5 may comprise a known type of energy meter arranged to measure the energy supplied to the user by the lines

LI and L2 feed.

  In the management circuit 1, the processing circuit 6 is connected to a memory 7, to a display circuit 8 and to a keyboard 9. A credit balance of energy C is stored in the memory 7. processing 6 decreases the amount of this credit balance according to the amount of energy used W, the information necessary for the measurement and / or calculation of the amount of energy used to be supplied by the measuring circuit 5. The amount of the credit balance stored can be changed by means of a code entered by the keyboard 9 accessible to the user. The display circuit 8 allows the user to know the

  amount of the stored credit balance, ie the remaining energy credit.

  When the amount of the credit balance stored in the management circuit is canceled, the processing circuit 6 controls the relay 4 so that it opens the contacts 3,

  causing the interruption of the supply of energy by lines LI and L2 to the user.

  In known devices, a supply circuit 10, connected to the lines L1 and L2, supplies the various components of the management circuit, as well as the relay 4 of the switch 2 via the circuit 1. The presence of the The supply voltage of the system is indicated by a light indicator 11, preferably constituted by a light-emitting diode. This is off in the absence of power supply voltage and on when the voltage supplied by the lines L1 and L2 to the management circuit 1 is sufficient. As a nonlimiting example, the voltage presence diode 11 is off when the voltage U between the lines is less than 160V and is constantly lit if the voltage U is greater than 160V. A first type of fraud, illustrated in Figure 2, is to completely bypass the energy control system which is de-energized. For this, the lines L1 and L2 are interrupted upstream (12) and downstream (13) of the assembly constituted by the management circuit 1 and the circuit breaker 2. The supply, permanently, of the user is provided by conductors L3 and L4 respectively connected to the lines L1 and L2 upstream and downstream of the interrupts 12 and 13 of the lines LI and L2. In this case, the management circuit 1 is no longer powered and the voltage presence diode 11 is off. Detection of this type of fraud,

known, however, is insufficient.

  Indeed, a second type of fraud, illustrated in FIG. 3, is not detected by the voltage presence diode. In this case, only the measuring circuit 5 is short-circuited. Lines LI and L2 are interrupted upstream (14) and downstream (15) of the measuring circuit. The continuity of lines LI and L2 is ensured respectively by conductors L5 and L6, respectively connected to lines L1 and L2, upstream and downstream of interrupts 14 and lines LI and L2. The supply circuit 10 of the management circuit 1 remains powered by the lines LI and L2 and the diode 11 of the presence of voltage remains on as long as the voltage on the lines LI and L2 is sufficient. However, the measuring circuit 5 being disconnected, the measurement of current and / or energy consumed supplied to the processing circuit remains zero and it can not take into account the energy consumed. The initial energy credit is therefore not reduced according to the actual energy consumption. The management circuit does not

can no longer fulfill its function.

  A third type of fraud, illustrated in FIG. 4, is also not detected by the voltage presence diode 11. In this case, only the circuit breaker 2 is short-circuited, by conductors L7 and L8 respectively connected to the lines L1 and L2 upstream and downstream of the circuit breaker 2. The management circuit 1 continues to operate normally. It is indeed powered and normally measures the energy consumed by the user. The voltage presence diode 11 is normally on. However, an opening order of the contacts 3 of the circuit breaker 2 does not interrupt the power supply of the user, who

  continues to be carried out via the L7, L8 drivers.

  The particular embodiment shown in FIGS. 5 and 6 makes it possible to signal the

  second and third type of fraud.

  As shown in the flowchart of FIG. 5, a sub-program of the energy measurement and calculation of the energy credit balance C comprises a first step F1 for measuring the voltage U between the lines L1 and L2, that is to say the voltage between phase and neutral for the single-phase network shown in Figures 1 to 4. Then, in a step F2, the voltage U is compared to a threshold. In Figure 5, this threshold is 160V. If U is below this threshold, the power supply is considered insufficient and the processing circuit loops back to step F1. When U reaches this threshold, the processing circuit goes to a step F3, in which a quantity M is set to a first value, 0 in Figure 5. Then, in a step F4, the message 00 is displayed. Then in a step F5, the processing circuit measures the current I supplied to it by the measuring circuit 5. In

  a step F6 it checks if the current I is zero. If it does, it loops back to step F5.

  Thus, the display remains 00 as long as the voltage U is sufficient, there is no energy consumption by the user since the last powering up of the circuit.

energy management 1.

  On the other hand, as soon as a non-zero current I is detected (output NO of step F6), the processing circuit goes to a step F7 where the quantity M is set to another value, 1 in FIG. display is then cleared (blank display) in a step F8, thus eliminating the

anomaly message 00.

  Then the processing circuit goes to a step F9 measuring the current I, the voltage U and

  the energy consumed W between two measurement cycles.

  In a step F10, identical to step F2, U is again compared to 160V. If U is insufficient, the processing circuit returns to step Fl. On the other hand, if U remains sufficient, it proceeds to a step FI1 in which the balance C is updated, the amount of the balance C being reduced by the amount W of the energy consumed. The processing circuit 6 then checks, in a step FIl1, whether the balance C remains positive. If the amount of the balance C is negative or zero (C. <0), then the processing circuit proceeds to open the contacts 3 of the switch during a step F13. For this, the processing circuit 6 controls the excitation of the relay 4 which opens the contacts 3. To feed its installation again, the user must manually reset the switch 2. However, any closure 1o contacts before entry in the management circuit 1 of a new, non-zero energy credit, via a credit code, automatically leads back to

opening of contacts 3.

  If the balance C is positive, the processing circuit returns to the measurement step F9 of I, U and W. In parallel with the energy measurement and calculation program of the balance C, the processing circuit performs the management of the energy according to the organization chart shown in

figure 6.

  In the particular embodiment shown, a management cycle begins with a step F14 during which the processing circuit checks whether a display has been requested by the user or whether a code has been entered. In practice, the display request and the beginning of the entry of a code can be made by the use of a predetermined identical key of the keyboard 9. The actuation of this key will have the same consequences at this level of the 'organizational chart. In the event of a request to display or enter a code, the processing circuit then proceeds, in a step F15, to the display of the balance C. This display is preferably done in alphanumeric form, the balance being expressed in KWH or in units

  predetermined amounts corresponding to the units used when purchasing an energy credit.

  After step F15, the processing circuit 6 checks, in a step F16 if a code has been entered. If this is the case, it processes this code, in known manner, in a step F17 before returning to step F14, at the beginning of the management cycle. Similarly, in the absence of entry

  code in F16, the processing circuit loops back to step F14.

  If, in F14, the processing circuit detects neither display request nor entry of a code, it proceeds to a step F18 during which it checks whether the magnitude M is 1. This amounts to detecting the existence of a power consumption after energizing the power management circuit 1, by detecting a non-zero current at any time from power on. In the absence of consumption since this power up (M = 0), the processing circuit goes to a step F19 signaling an anomaly. In the particular embodiment shown in FIG. 6, this signaling is carried out in the form of display by the display circuit 8 of the abnormal message constituted by the alphanumeric message 00. The processing circuit then returns to

step F14.

  In this way, as long as no power consumption is detected after powering on the management circuit, the management routine permanently displays the fault signal (F19), except, temporarily, when the display credit balance C is requested (F14, F15) or when a code is entered (F14 to F17). It is thus possible to detect the second type of fraud illustrated in FIG.

management circuit 1.

  Since the measuring circuit is short-circuited, no energy consumption is measured and the energy credit C does not decrease. The invention makes it possible, thanks to the verification (F18) of the existence of a consumption (M = 1) from the powering up of the circuit of

  management, to report the existence of an anomaly.

  However, the absence of energy consumption (M = 0) for a certain time after power up is not necessarily synonymous with fraud. It is possible that the user does not use his electrical installation for a certain time. It is therefore planned to delete the fault message as soon as a consumption is detected (in F6) after switching on the power supply. In addition, before using his installation, the user can nevertheless proceed to the entry of a code or request the display of C. The display of the anomaly 00 then disappears momentarily. Step F18 makes it possible to check the state of M. When, in step F18, M = 1, the processing circuit goes to a step F20 for comparing the balance C of energy credit with an alert threshold. predetermined. If C is greater than this threshold, the processing circuit proceeds to a step F21 in which the S anomaly message is cleared. In practice, the display then preferably remains empty. Then

  the processing circuit returns to the beginning of the management cycle.

  If the balance C is less than or equal to the alert threshold, an alert phase F22, displaying the balance C is performed. Then, in F23, the credit balance is compared to a negative or zero threshold. If C is greater than this new threshold, then the processing circuit proceeds to step F16. Otherwise, this means that the contacts 3 were not opened during the cancellation of the credit which should have been detected in F12 by the sub-program for measuring and calculating C which takes place in parallel. The processing circuit then goes to an opening step F24, followed by a step F25 signaling a fraud. In FIG. 6, this signaling is effected by the display of a particular message PROBL.

  It must draw attention to the existence of a problem. If, contacts, not short-

  circuits open, then the user's power supply is interrupted and the measured current is canceled. In a step F26, the processing circuit verifies the correct opening of the contacts. If the contacts are open, the circuit loops back to step F16, then returns, possibly after a step F17 at the beginning of the management cycle. If a credit code has been entered, C will normally be higher than the alert threshold (NO output of F16) and the display of the PROBL message will go off. In the absence of entry of a new credit, it will return to step F22 warning and display of C, and the message PROBL will also disappear. On the other hand, if the contacts 3 are short-circuited as shown in FIG. 4, the opening of the contacts does not prevent the power supply of the user. The management circuit 1, operating correctly, detects this fraud in step F26 because the current I measured does not cancel. It then loops back to step F24 and continues to display the

PROBL message.

  It is preferable that the comparison threshold used in step F23 is negative rather than zero in order to avoid an unwanted display of the PROBL message, for example to take account of the consumption during the period separating the decision to open the contacts of the actual opening of these. In the embodiment shown, this threshold is -5 energy units. The management channel will deduct a negative credit from a new credit entered at a later date.

means of a credit code.

  The particular embodiment shown in the figures thus makes it possible to detect the following three types of fraud: bridging of the entire management circuit and the circuit breaker (FIG. In this case, the fraud is

  signaled by the extinction of the diode 11 of presence of voltage.

  - bridging of the measuring circuit 5 of the management circuit (FIG 3). This fraud, performed off, is detected (F 18) by the fact that no consumption is detected by the management circuit when it is turned back on. Fraud is indicated by an error message 00

(F19).

  - bridging of the circuit breaker alone, the management circuit remaining normally powered and correctly measuring the energy consumed. The transition from the credit balance to a negative value is

  signaled by a PROBL message. (F 25).

  Thus, any attempt of fraud off is reported electronically as soon as the voltage is restored. When the display is disposed outside the premises of the user, that is to say accessible to an inspector, the display of these messages allows the latter to detect an attempted fraud. If the display is located inside the premises, in a location not freely accessible to an inspector, then it may be provided to transmit these messages to an external control center. This can for example be achieved by means of

  carrier currents or by radio waves.

  In the embodiment shown in the figures, the electrical network is single-phase.

  The invention applies in the same way to a three-phase network. In this case, the voltage U corresponds to the voltage between each phase and the neutral and is preferably considered sufficient if the voltage between at least two phases and the neutral is greater than

threshold chosen.

It

Claims (5)

  1.-Prepaid energy control system comprising means (1) for energy management comprising fraud detection means, said fraud detection means comprising means (11) for signaling the presence of voltage, system characterized in that the fraud detection means comprise means (F6, F7, F18) for detecting the existence of a power consumption from the energization of the energy management means (1) , and means (8, F19) signaling a anomaly in his absence.   2. System according to claim 1, characterized in that the means for detecting the existence of a power consumption comprise means (5) for measuring current.   3. System according to one of claims 1 and 2, characterized in that the means of   energy management comprise extinguishing means (F8, F21) means of   signaling an anomaly when a power consumption is detected.   4. System according to any one of claims 1 to 3, characterized in that the   energy management means comprising means (7, 9) for entering and storing an energy credit, means (5, F9) for measuring the amount of energy (W) consumed by a user, means (F11) for determining an energy credit balance (C) according to said energy credit and the quantity of energy consumed, the fraud detection means comprising means (F23) detecting a negative energy credit balance and means (F25) for signaling a fraud when said balance is negative.   5. System according to claim 4, characterized in that the means (F23) for detecting a negative credit balance comprise means for comparing the credit balance and   a predetermined negative threshold.