FR2664059A1 - Device for identifying phases in a low voltage multiphase electricity distribution network - Google Patents

Abstract

A device for identifying the phases in a low voltage multiphase electricity distribution network. The device comprises means (1) for sending over each phase a coded identification signal and means (2) for receiving and thus detecting the coded identification signal for each phase. Means for identifying each phase are provided from the coded identification signal received and detected. Application to the maintenance and running of low voltage electricity distribution networks.

Description

Device for tracking the phases of a low-voltage polyphase electricity distribution network
The present invention relates to a device for tracking the phases of a low-voltage polyphase electricity distribution network, the network being on or off.

 Currently, to identify the phases of a low-voltage polyphase electricity distribution network cable, of the insulated twisted cable type for example, the cable must be recorded and isolated from any receiver, the phases being identified by means of a battery. , ohmmeter or similar device.

Another method may consist in switching the phases off or on depending on whether the cable is in operation or being received.

The latter method, although sometimes used, is not recommended, in particular because of the risks caused by the appearance of imbalances on the network during the corresponding tests.

 The object of the present invention is to remedy the aforementioned drawbacks by the use of a device for tracking the phases of a low-voltage polyphase electricity distribution network, the tracking being able to be carried out with the network being powered on or off. . The device for locating the phases of a low-voltage polyphase electricity distribution network, object of the present invention, is remarkable in that it comprises means for transmitting on each phase a coded identification signal and means for receiving, for each phase, the identification signal making it possible to detect this signal. Means of identification of each phase are provided for carrying out this identification from the coded identification signal received and detected.

The device for identifying the phases of a low-voltage polyphase electricity distribution network according to the present invention can advantageously be used by the maintenance and management services of low-voltage electricity distribution networks to balance the low voltage networks in the absence of power off, with a corresponding improvement in the quality of services and better management of the transformer fleet
MT / BT. I1 also makes it possible to ensure the identification of the ends of a cable that is live or off.

The device object of the present invention will be described in more detail in conjunction with the description below and the drawings in which
- Figure 1 shows a general diagram re
presentation of the device object of this
invention,
- Figure 2a shows a block diagram
transmitting means constituting the device
subject of the present invention,
- Figure 2b shows a block diagram
receiving means constituting the device
subject of the present invention,
- Figure 2c shows a timing diagram of
different code signals issued for each
phase of an electric distribution network
low-voltage three-phase tee,
- Figure 3 shows the diagram of a mode of
realization given as an example of a
code issuer in accordance with the subject of the
present invention,
- Figure 4 shows the diagram of a mode of
realization given as an example of a
code receiver according to the subject of the
present invention.

 The device for tracking the phases of a low-voltage polyphase electricity distribution network which is the subject of the invention will be described in more detail in conjunction with FIG. 1.

In accordance with the aforementioned figure, the device according to the invention comprises means 1 for transmitting on each phase denoted P1, P2, P3 a coded identification signal. The successive coded signals are denoted CO1,
C02, C03 in FIG. 1. In addition, the device according to the invention comprises means 2 for receiving for each phase the coded identification signal making it possible to detect the aforementioned coded identification signal. Means 2 for receiving are provided with means denoted 251, 261, 271 for identifying each phase from the coded identification signal received and detected. It will of course be noted that, at the level of receiver 2, the phases are denoted P because, in particular at the level of low voltage distribution network cables, in particular twisted cables, it is not possible to determine the order of the phases P1, P2, P3 apart from the implementation of the methods used up to 'to date as described in the introduction to the description.

Of course, the transmission means 1 allow the transmission of a coded identification signal consisting of a plurality of distinct codes, the codes Col, C02,
C03 above, a code being associated with a phase of the polyphase network. Thus, the transmitter transmits on the network 50
HZ and the transmitter 1 is connected to the aforementioned network by means of three connection conductors, the three conductors possibly being provided with a color marking, for example green, yellow, red respectively for the phases P1, P2, P3. In addition, the transmitter 1 is connected to the neutral of the network.

It will of course be understood with regard to the receiver 2 that the latter comprises a connection to one of the aforementioned phases P, the identification means 251, 261, 271 allowing the emission of a color light signal corresponding to phase P1 or P2 or
P3 considered according to the code signal CO1, C02 or C03 detected and according to the color code used for the connection of the transmitter 1 to the phases P1, P2, P3.

A more detailed description of a functional diagram of the transmitter 1 will now be given in connection with FIG. 2a. According to the aforementioned figure, the transmission means 1 comprise for the transmission of a code relating to a phase c ′, that is to say of a code CO1 or C02 or
C03, means denoted 10, 11 generators of a square signal denoted CLK at the frequency and according to a phase relation determined with respect to the network voltage of the phase considered. It will thus be understood that the square signal CLK is a synchronous signal of the phase signal P1,
P2 or P3, this CLK signal being able to be delivered by a circuit of the clipping circuit type 10 followed by a counter 11 which makes it possible to deliver a number of successive square signals determined as will be described later in the description. the transmission means 1 comprise encoding means 12 making it possible to generate a coded modulation signal denoted co according to a predetermined code representative of the corresponding phase of the polyphase network.

 As has also been shown in FIG. 2a, the transmitter comprises a local oscillator 14 making it possible to generate a signal of the carrier signal type at medium frequency denoted fm. Preferably, the local oscillator 14 is constituted by an 80 KHZ oscillator making it possible to deliver the aforementioned signal fm.

A modulator or mixer stage 13 receives on the one hand the coded modulation signal co and on the other hand the carrier signal at medium frequency fm and makes it possible to generate the code COI, C02 or C03 associated with the phase of the polyphase network. It will of course be understood that the code
CO1, C02 or C03 is in fact determined by the corresponding coded modulation signal co delivered by the encoder 12.

 The modulator or mixer stage 13 is then followed by a power stage denoted 15 which makes it possible to amplify the code associated with the phase of the polyphase network P1 or P2 or P3. In FIG. 2a, it has been indicated that the power stage delivered the same signal of code CO1, C02 or C03, this code of course being identical but corresponding to a signal amplified with respect to the signal delivered by the mixer or modulator stage 13 .

An adapter stage 16 then receives the amplified coded signal CO1, C02 or C03, the adapter stage 16 being in operation connected between a remarkable point of phase P which one wishes to identify and the neutral
N of the polyphase network.

 FIG. 2b shows the functional diagram of the reception means 2 or receiver constituting the device according to the invention.

 According to the aforementioned figure, the receiver 2 comprises an input channel 20 intended in operation to be connected between one of the phases P of the cable of the low voltage distribution network and the neutral of the latter. This input channel 20 makes it possible to deliver the detected coded identification signal, denoted cod, and corresponding to one of the coded signals CO1, C02 or C03.

 The receiver 2 further comprises a square signal generator 21 delivering the square signal denoted CLK at the network frequency and according to a phase relation determined with respect to the network voltage of the phase P considered.

 In addition, the receiver 2 as shown in FIG. 2b comprises a phase decoding channel of the distribution network. Each decoding channel is connected on the one hand to the input channel 20 and on the other hand to the square signal generator means 21. It will be noted that in FIG. 2b without limitation, three decoding channels are simply shown denoted 22, 23, 24, this for the case where the network is a three-phase network.

Each decoding channel 22, 23, 24 delivers a sip phase identification signal from the detected coded signal cod. As will be seen in FIG. 2b, the means for identifying each phase of the receiver 2 denoted 25, 26 and 27 comprise a visual signaling device representing the phase of the network denoted 251, 261, 271, in addition , the input channel 20 comprises an adapter circuit 200 and a detector circuit 201 connected in cascade and delivers the coded identification signal detected cod.

Each decoding channel 22, 23, 24 finally comprises a specific decoder circuit receiving the square signal CLK and the detected coded identification signal cod and delivers the phase identification signal sip. It will be noted that the specific decoder circuits may be constituted by decoder circuits sold under the reference MM53200 by the company National
Semi Conductors.

 Preferably, as also shown in FIG. 2b, the visual signaling device comprises a timing circuit 250, 260 or 270 receiving the decoded identification signal and for example an electroluminescent diode 251, 261 or 271, each electro diode luminescent being for example a diode of color determined for the phase considered. The color of the diodes corresponds to the color of the connection wires of the transmitter 1 to the phases P1, P2, P3 and of course to the corresponding codes CO1, C02, C03.

As shown in addition in FIG. 2c, and in order to avoid any overlapping of the codes CO1, C02, C03 with one another, the latter relating to each phase
P1, P2, P3 are not transmitted simultaneously. Preferably, as shown in FIG. 2c, the transmissions synchronous with the coded phase are made phase by phase with a determined time offset. This time offset can be taken for example equal to 33 ms. Consequently, even if the code transmitted on phase 1 for example corresponding to the green color code pollutes phase 2 corresponding for example to the yellow color code and phase 3 corresponding to the red color code, the receiver 2 whose decoding is synchronous with the phase tested will receive the entire code COl if the green phase or phase number 1 is tested and only part of it if it is the other phases 2 or 3, that is to say yellow or red, which are tested. This offset to the emission of codes CO1, C02 and C03 makes it possible to increase the reliability of the detection system object of the invention.

 A more detailed description of the transmitter or transmission means 1 as shown in FIG. 2a will be given in conjunction with FIG. 3.

 In the aforementioned figure, the embodiment shown is that relating to one of the phases P1, P2 or P3, the corresponding circuits relating to the other phases of course being arranged in a similar manner.

Only the code assigned to the corresponding phase, that is to say CO1, C02 or C03 being different. In FIG. 3, it will be noted that the square signal generator circuit 10 makes it possible to transform the network voltage to 50
HZ as a square signal by means of the circuit RCC1 and the clipping diode D, a photocoupler denoted OC making it possible to ensure the galvanic isolation of the emitter 1 from the network voltage. In addition, a shaping circuit
MF makes it possible to give a clean square signal, the shaping circuit comprising a NAND gate as a trigger.

The square signal delivered by circuit 10 is delivered to a counting circuit 11 this square signal delivered by circuit 10 being connected to the clock of a counter marketed under the reference CD 4017A by the Company
National Semi Conductors. The CD counter 4017A is wired modulo 8. It will be noted that for phase Pi the output 2 of the counter will allow control of the encoder 12 while for phase n "2 the output n" 4 of the aforementioned counter will control the encoder 12 and for phase n "3 or red the output n" 6 of the counter will control the encoder 12, these latter circuits not being shown in FIG. 2a for the aforementioned yellow and red phases n "2 and n" 3. codes CO1, C02, C03 relating to each phase are emitted every 160 ms which makes it possible to ensure compatibility with the desired result.

As regards the encoder 12 previously described in the description, this consists of the circuit MM53200 sold by the company National
Semi Conductors.

 An external clock, not shown, makes it possible to deliver a signal at 100 KHZ in order to generate the coded modulation signal co in 11.52 ms. Since half of the line voltage has a duration of 10 ms, the above-mentioned external clock can be modified in order to deliver the modulation signal coded in 5.5 ms in order to be certain that all of the code CO1, C02 or C03 is emitted during the 10 ms of the above-mentioned alternation.

 In this case, the previously mentioned clock frequency can be increased to 425 KHZ.

According to a nonlimiting embodiment, the coded modulation signal co can have the following values for the phases P1 respectively P2 respectively P3
- 1111 0000 0000 for phase 1 or green phase,
- 0000 1111 0000 for phase P2 or phase
yellow,
- 0000 0000 1111 for the red phase or phase 3.

 The encoder is in fact only made active on command of the signal delivered by the counter 11 previously described.

 In addition, as shown in FIG. 3, the oscillator includes an oscillator circuit produced from NAND type circuits with resistance R and with capacity Q. A shaping stage MF is also used for shaping the rectangular type signals delivered by the above oscillator circuit.

 As far as the mixer or modulator stage 13 is concerned, it will be noted that this essentially comprises a logic AND gate 130 whose inputs are validated by the coded modulation signal co delivered by the encoder 12 and the fm signal delivered by the local oscillator 14. The logic gate ET 130 thus makes it possible to ensure modulation of the signal at 80 KHZ by the aforementioned code signal. Note that an MF shaping stage produced in the form of a NAND gate trigger is also provided.

The signals of codes CO1, C02 or C03 delivered by the mixer or modulator stage 13 are then amplified by the power stage 15 via a current amplifier in common collector constituted by the transistor T1 followed by a Darlington type assembly constituted by the transistors T2 and T3 charged by a TH tiristor used for its almost zero voltage when switching. The code thus amplified is injected on the network between the phase to be coded Pi for example and the neutral by an adapter circuit 16, which is constituted by a capacitive circuit C3. This capacitive circuit has a high impedance at the network frequency at 50 HZ and a low impedance at 80
KHZ.

 Note that in Figure 3 all of the elements designated by R, C, C1, D and C3 are electronic components whose values can be easily determined by those skilled in the art in the application considered. With regard to the supply voltages, it will be noted that these are designated by the general designation + VCC, this designation corresponding to a value of 10 Volts for the counting circuits and the logic circuits as well as the oscillator local and at a value of 24 Volts for the power stage for example.

 A more detailed description of the receiver 2 will also be given in connection with FIG. 4.

 In FIG. 4, the same references represent the same elements as in FIG. 2b.

 It will be noted in particular that the receiver consists of two parts, a common part relating to the detection and the reshaping of the code signal transmitted on the phase considered and a part specific to each phase.

 As regards the square signal generator circuit 21, it will be noted that this is identical to the square signal generator circuit 10 of the transmitter 1.

It will of course be understood that the square signal generator circuit 21 ensures synchronization of the coding with respect to the transmission at the receiver by authorizing the start of the decoding in a synchronized manner. Synchronization takes place at each decoding channel 22, 23, 24.

 As regards the input channel 20, this comprises an adapter 200 with capacitance C and resistance R followed by a detector circuit 201. The detector circuit 201 in fact constitutes a high pass filter with cutoff frequency greater than 50 HZ, that is to say the frequency of the network voltage while ensuring the transmission of the useful signal, the signal at 80 KHZ modulated by the code.

The two Zener Dz diodes mounted head-to-tail ensure clipping of any overvoltages present in the form of parasitic pulses. An operational amplifier and a transistor T4 mounted as a common emitter make it possible to amplify the useful signal at 80 KHZ, representative of the aforementioned code CO1, C02, C03. At the output of transistor T4, two logic circuits of the AND type associated with two capacitors C make it possible to form low-pass filters making it possible in fact to suppress the carrier signal at 80 KHZ. Note that a door
NON-AND then makes it possible to reverse the code previously reversed by the transistor T4 mounted as a common emitter.

The four successive AND type logic circuits associated with the corresponding resistors R and C then ensure a reshaping of the signal delivered after removal of the carrier at 80 KHZ to generate the detected code signal cod, which is delivered to each of the decoders constituting the decoding channels 22, 23 and 24.

 As regards the part specific to each phase, the circuits for a three-phase network are of course three in number, one for each of the aforementioned phases. These circuits are identical and only one of these circuits is thus represented in FIG. 4. Of course, for each phase, the coding of the decoders will be different and the decoding circuit relating to phase 1 or green phase has the code 1111 0000 0000, the circuit relating to phase 2 or yellow phase has the code 0000 1111 0000, and the circuit relating to the red phase or phase 3 has the code 0000 0000 1111.

If the code present, i.e. the code represented by the coded signal detected cod at the input terminal of the decoding channel 22, 23 or 24, corresponds to the code assigned to the decoding circuit MM53200 constituting each of the above-mentioned decoding channels during the decoding authorization given by the square signal CLK, the output terminal of the above-mentioned decoder changes state and goes from high to low state for a short time. This change of state in fact constitutes the signal indicating phase sip previously mentioned. The timing circuit 250, 260 or 270 then receives the aforementioned signal signal indication of phases sip, these timing circuits can be constituted by circuits of the NE555 type marketed by the company
National Semi Conductors and mounted in monostable mode. The triggering of the above-mentioned timing circuits then supplies a light-emitting diode 251, 261 or 271 whose green, yellow or red color code corresponds to the phase P1, P2 or P3 previously mentioned. .

 It will be noted that, instead of the oscillator circuit constituting the local oscillator 14, the clock of the encoder 12 and the decoder 22, it may be advantageous to use a quartz circuit, this in order to reduce the oscillation frequency and clock drifts to give better reliability to the system. In addition, while retaining a high pass filter at the receiver 2, the circuits downstream of the latter can advantageously be replaced by an active quartz filter set on the carrier frequency of 80 KHZ.

 We have thus described a device for locating a low-voltage polyphase electricity distribution network which is particularly efficient insofar as this device remarkably makes it possible to locate while the distribution network is kept under tension. Such a device makes it possible in particular to carry out, if necessary, any phase rebalancing operation without requiring the interruption of subscriber service.

Claims (8)

 1. Device for tracking the phases of a low-voltage polyphase electricity distribution network, characterized in that it comprises  - transmission means (1), on each phase,  a coded identification signal,  - reception means (2), for each pha  se, of the coded identification signal, allows  both to detect the identification signal  coded, means (251, 261, 271) of identification  tion of each phase, from the signal  coded identification received and detected.  2. Device according to claim 1, characterized in that said transmission means (1) allow the transmission of a coded identification signal consisting of a plurality of successive distinct codes (COi, C02, C03), a code being associated with a phase of the polyphase network.  3. Device according to claim 2, characterized in that said transmission means (1) comprise for the transmission of a code relating to a phase  - means (10,11) generating a signal  (CLK) square at the frequency and, according to a rela  phase phase determined in relation to the  network voltage of the phase considered,  - encoding means (12) for generating  drer a coded modulation signal (co) according to  a predetermined code representative of the phase  correspondent of the polyphase network,  - a local oscillator (14) allowing engen  drer a medium frequency carrier signal  (fm),  - a modulator stage (13) receiving on the one hand  the coded modulation signal (co) and other  share carrier signal at medium frequency  (fm) and allowing to generate the code (COi,  C02 or C03) associated with said phase of the network  polyphase,  - a power stage (15) allowing am  fold the code associated with said phase of the re  polyphase bucket,  - an adapter stage (16) receiving said code  amplified (Coi, C02, C03), this adapter stage  being, in operation, connected between a point  remarkable of said phase (P) and neutral  (N) of the polyphase network.  4. Device according to claim 1, characterized in that the receiving means (2) comprise:  - an input channel (20) intended for use  to be connected between said phase and the  neutral of the polyphase network and to deliver the  coded identification signal detected (cod),  - means (21) generating a square signal  (CLK) at the network frequency and according to a  phase relationship determined with respect to the  network voltage of the phase considered,  - one decoding channel per phase of the  distribution, each decoding channel being  connected on the one hand to the entry way and at  be part of the signal generating means  square, each decoding channel delivering a  phase identification signal (sip), through  shot of the detected coded signal (cod).  5. Device according to claim 1, characterized in that said means for identifying each phase comprise a visual signaling device for representing said phase of the network.  6. Device according to one of claims 4 or 5, characterized in that said input channel (20) comprises an adapter circuit (200) and a detector circuit (201) connected in cascade delivering the detected coded identification signal (cod).  7. Device according to one of claims 4 to 6, characterized in that each decoding channel comprises a specific decoder circuit receiving said square signal (CLK) and the coded identification signal, detected (cod) and delivering a signal d phase identification (sip).  8. Device according to one of claims 5 to 7, characterized in that the visual signaling device comprises a timing circuit (250) receiving said phase identification signal (sip), and an electroluminescent diode (251) of color determined for the phase considered.