AU2013206748A1 - Measuring system for measuring at least one electrical quantity, electrical transforming staton comprising such a measuring system and associated measuring method - Google Patents

Abstract

MEASURING SYSTEM FOR MEASURING AT LEAST ONE ELECTRICAL QUANTITY, ELECTRICAL TRANSFORMING STATION COMPRISING SUCH A MEASURING SYSTEM AND ASSOCIATED MEASURING METHOD This measuring system (20) is able to measure at least one electrical quantity relative to a power installation. The power installation comprises three electrical conductors able to enable the flowing of a three-phase alternating current. The measuring system comprises a voltage measuring element (66) for measuring 5 voltage of each of the electrical conductors, each electrical conductor being associated to a respective phase of the alternating network, an information processing unit (68) able to receive the values of the measured voltages, and three current sensors (76A, .. , 76N), each current sensor being able to measure the intensity of the current flowing in the corresponding electrical conductor. 10 The processing unit (68) comprises associating means (103) for associating in a predetermined manner the first measured voltage with a first phase among the three phases and a first identifying device (101) for identifying the phase corresponding to each of the two other measured voltages. The processing unit (68) comprises a second identifying device (125A, ..., 125N) for 15 identifying the phase corresponding to each of the three measured intensities. Figure 2

Description

DESCRIPTION This invention relates to a measuring system for measuring at least one electrical quantity relative to a power installation, the power installation comprising electrical conductors able to enable the flowing of a three-phase alternating current. This measuring system comprises a voltage measuring element for measuring the 5 voltage of each of the electrical conductors, each electrical conductor being associated to a respective phase of the alternating network, an information processing unit able to receive the values of the measured voltages, and three current sensors, each current sensor being able to measure the intensity of the current flowing in the corresponding electrical conductor. 10 This invention further relates to a transforming station for transforming an electric current having a first alternating voltage into an electric current having a second alternating voltage, the transforming station comprising such a measuring system. This invention further relates to a measuring method for measuring at least one electrical quantity using such a measuring system. 15 It is known from document US 7,425,778 B2 a measuring system of the aforementioned type. The measuring system belongs to a differential protection relay connected to the primary and to the secondary of a transformer. This measuring system makes it possible in particular to detect a possible crossing of connections between phases on inputs of the differential protection relay. To that effect, the 20 information processing unit of the measuring system calculates the current during a negative sequence as a percentage of the current during a positive sequence, and declares a connection error when the quantity of current during a negative sequence is greater than a predefined rate, such as a rate of 10%. However, such a measuring system indicates, where applicable, only one connection 25 error, without providing further information. The purpose of the invention is therefore to propose a measuring system at least one electrical quantity relative to a multi-phase power installation making it possible to identify the phase corresponding to each of the measured voltages. To that effect, the subject-matter of the invention concerns a measuring system of the 30 aforementioned type, characterised in that the processing unit comprises associating means for associating in a predetermined manner the first measured voltage with a first phase among the three phases, a first identifying device for identifying the phase corresponding to each of the two other measured voltages and a second identifying 2 device for identifying the phase corresponding to each of the three measured intensities. According to other advantageous aspects of the invention, the measuring system comprises one or several of the following characteristics, taken separately or according 5 to all technically admissible combinations: - the first identifying device comprises first means for determining the Fresnel vector of each of the three measured voltages, first means of calculating an image vector via a first rotation of the Fresnel vector of one among the two other measured voltages and first comparison means for comparing the image vector with the Fresnel vector of the 10 first measured voltage; - an index kp is associated to each phase to be identified, the index kP being an integer equal to 1 for the first phase and taking successively the integer values equal to 2 and 3 for the other phases, and the value of the angle of the first rotation depends on the index kp of the phase to be identified, the value of the angle of the first rotation being 15 more preferably equal to (kp-1) x 120; - the second identifying device comprises second determining means for determining the Fresnel vector of each of the three measured intensities, second calculation means for calculating three image vectors via a second rotation of the Fresnel vectors of the three measured intensities and second comparison means for comparing, with a 20 predetermined interval of angular values, the value of the angle between each image vector and a reference axis; - an index kp is associated to each phase to be identified, the index kp being an integer equal to 1 for the first phase and taking successively the integer values equal to 2 and 3 for the other phases, and wherein the value of the angle of the second rotation 25 depends on the index k, of the measured intensity; - the value of the angle of the second rotation is equal to ((k,-1) x 120") - R, where R represents the value of the angle between the Fresnel vector of the first measured voltage and the reference axis; - the second identifying device comprises second means for determining the Fresnel 30 vector of each of the three measured intensities, and third comparison means for comparing, for each measured intensity, coordinates of the Fresnel vector of said measured intensity with the coordinates of the Fresnel vector of a respective measured voltage; 3 - the measuring system further comprises an indication device for indicating the end of identification able to emit a first signal, such as a first lighted signal, when the first device identified the phase corresponding to each of the measured voltages; and - the measuring system is provided for a power installation comprising primary 5 electrical conductors and secondary electrical conductors able to enable the flowing of the alternating current, each secondary electrical conductor being electrically connected to a corresponding primary electrical conductor, with the primary conductor and the corresponding secondary conductor having substantially the same alternating voltage, 10 wherein the measuring system comprises: - a primary module comprising the voltage measuring element, the voltage measuring element being able to measure the voltage of each primary conductor, - at least one secondary module comprising the three current sensors, each current sensor being able to measure the intensity of the current flowing in the corresponding 15 secondary conductor, with the or each secondary module being connected to the primary module by a corresponding data link, the primary module further comprising means for emitting, to the radio receiver of the or of each secondary module, a first message containing the values of measured voltages, 20 the or each secondary module comprising reception means for receiving the first message, and the measuring system comprising means for time synchronisation of the measured intensities in relation to the measured voltages. The subject-matter of the invention also concerns a transforming station for 25 transforming an electric current having a first three-phase alternating voltage into an electric current having a second three-phase alternating voltage, the transforming station comprising: - a first board comprising input electrical conductors able to be connected to an electrical network, each input conductor being associated to a respective phase of the 30 first alternating voltage, - a second board comprising primary output electrical conductors and secondary output electrical conductors, each secondary output conductor being connected electrically to a corresponding primary output conductor, each output conductor being associated to a respective phase of the second alternating voltage, 4 - an electric transformer connected between the first board and the second board and able to transform the first alternating voltage into the second alternating voltage, and - a measuring system at least one electrical quantity relative to the second board, characterised in that the measuring system is such as defined hereinabove. 5 The subject-matter of the invention also concerns a measuring method for measuring at least one electrical quantity relative to a power installation, with the installation comprising electrical conductors able to enable the flowing of a three-phase alternating current, with the method comprising the following steps: - measuring, by a voltage measuring element, the voltage of each of the electrical 10 conductors, each electrical conductor being associated to a respective phase of the alternating network, - receiving, by an information processing unit, the values of the measured voltages, the measuring method being characterised in that it further comprises the following steps: 15 - associating, by the information processing unit, in a predetermined manner the first measured voltage with a first phase among the three phases, - identifying, by a first identifying device, the phase corresponding to each of the two other measured voltages, - measuring, by three current sensors, the intensity of the current flowing in each of the 20 electrical conductors, and - identifying, by a second identifying device, the phase corresponding to each of the three measured intensities. According to other advantageous aspects of the invention, the measuring method comprises one or several of the following characteristics, taken separately or according 25 to all technically admissible combinations: - the step of identifying the phase corresponding to each of the three measured intensities comprises determining the Fresnel vector of each of the three measured intensities, calculating three image vectors via a second rotation of the Fresnel vectors of the three measured intensities and comparing, with a predetermined interval of 30 angular values, the value of the angle between each image vector and a reference axis; and - an index k, is associated to each phase to be identified, the index kp being an integer equal to 1 for the first phase and taking successively the integer values equal to 2 and 3 for the other phases, and wherein the value of the angle of the second rotation 35 depends on the index kp of the measured intensity, the value of the angle of the second 5 rotation being more preferably equal to ((kp-1) x 120") - R, where R represents the value of the angle between the Fresnel vector of the first measured voltage and the reference axis. These features and advantages of the invention will appear when reading the following 5 description, provided solely by way of non-restricted example, and made in reference to the annexed drawings, wherein: - figure 1 is a diagrammatical representation of a transforming station comprising a first board, a second board connected to the first board by the intermediary of a transformer and a measuring system at least one electrical quantity relative to the second board, 10 - figure 2 is a diagrammatical representation of the measuring system of figure 1, the measuring system comprising a primary module for measuring voltage, a plurality of secondary modules for measuring intensity and a module for centralising, - figure 3 is a diagrammatical representation of the secondary module of figure 2, - figure 4 is a Fresnel representation of the voltages and currents measured, 15 - figure 5 is a flow chart of the steps of a measuring method for measuring, relative to the identification of the phase corresponding to each of the measured voltages, - figure 6 is a flow chart of the steps of the measuring method relative to the identification of the phase corresponding to each of the measured intensities, according to a first embodiment of the invention, and 20 - figure 7 is a view similar to that of figure 6 according to a second embodiment of the invention. In figure 1, a transforming station 10 connected to an electrical network 12 comprises a first board 14, a second board 16, an electric transformer 18 connected between the first board and the second board, and a measuring system 20 for measuring at least 25 one electrical quantity relative to the second board 16, such as the value of the alternating voltage and/or of the alternating current associated to the second board 16. The transforming station 10 is able to transform the electric current delivered by the network 12 and having a first alternating voltage, into an electric current having a second alternating voltage. 30 The electrical network 12 is a medium-voltage network, i.e. a network of which the voltage is greater than 1,000 Volts and less than 50,000 Volts. The first three-phase voltage is thus a medium voltage. Alternatively, the network 12 is a three-phase alternating network. The electrical network 12 is a high-voltage network, i.e. a network of which the voltage is greater than 35 50,000 Volts. In other words, the first three-phase voltage is high voltage.

6 Alternatively, the electrical network 12 is a medium-voltage network, i.e. a network of which the voltage is greater than 1,000 Volts and less than 50,000 Volts. The first three-phase voltage is then a medium voltage. The first board 14 comprises several inputs 22, with each input 22 comprising a first 5 24A, 24B, a second 26A, 26B, and a third 28A, 28B input conductors. Each first, second, third input conductor 24A, 24B, 26A, 26B, 28A, 28B is connected to the electrical network by the intermediary of a respective input circuit breaker 32. The three-phase current flowing in the corresponding input conductors 24A, 24B, 26A, 26B, 28A, 28B has the first three-phase voltage. 10 The second board 16 comprises a first 34, a second 36, a third 38 and a fourth 39 primary conductors and a plurality N of outputs 40A, 40B, ...40N, i.e. a first output 40A, a second output 40B, ... , an Nth output 40N, each output 40A, 40B, ..., 40N being able to deliver a three-phase voltage. Each output 40A, 40B, 40N is a low-voltage output, i.e. an output of which the voltage 15 is less than 1,000 Volts. The second three-phase voltage is then low voltage. Alternatively, each output 40A, 40B, ..., 40N is a medium-voltage output, i.e. an output of which the voltage is greater than 1,000 Volts and less than 50,000 Volts. In other words, the second three-phase voltage is a medium voltage. The first output 40A comprises a first 42A, a second 44A, a third 46A and a fourth 48A 20 secondary conductors and three output circuit breakers 50. The first, second and third secondary conductors 42A, 42B, 42C are respectively connected to the first, second and third primary conductors 34, 36, 38 by the intermediary of a corresponding output circuit breaker 50. The fourth secondary conductor 48A is directly connected to the fourth primary conductor 39. 25 The primary output conductors 34, 36, 38 and the corresponding secondary output conductors 42A, 44A, 46A have substantially the same voltage, i.e. respectively a first voltage V1, a second voltage V2 and a third voltage V3 corresponding to the three phases of the second three-phase voltage. The three-phase voltage of the primary conductors 34, 36, 38 and of the secondary output conductors 42A, 44A, 46A has a 30 frequency Fggage and a period Pvitage. The other outputs 40B, ...40N are identical to the first output 40A described previously, and comprise the same elements by replacing each time the letter A with the corresponding letter B, ..., N concerning the references of the elements. The electric transformer 18 is able to transform the current coming from the electrical 35 network having the first alternating voltage into the current delivered to the second 7 board 16 and having the second alternating voltage. The electric transformer 18 comprises primary windings 52 connected to the first board 14 and secondary windings 54 connected to the second board 16. The measuring system 20 is able to measure the voltage of each secondary output 5 conductor 42A, 44A, 46A,... 46N. In addition, the measuring system 20 is able to measure the intensity of the current flowing in each secondary output conductor 42A, 44A, 46A, ...46N. The measuring system 20, visible in figure 2, comprises a primary module 60, a plurality N of secondary modules 62A, 62B, ..., 62N, i.e. a first secondary module 62A, 10 a second secondary module 62B, not shown, ... and an Nth secondary module 62N, and a centralising module 64. Each secondary module 62A, ... , 62N is connected to the primary module 60 by one corresponding data link, not shown. The primary module 60 comprises a voltage measuring element 66 for measuring voltages of the corresponding primary conductors 34, 36, 38, and an information 15 processing unit 68. The primary module 60 further comprises a radio transceiver 70, a radio antenna 72, when the data links connecting the primary module to the secondary modules are radio links, and a supplying member 74 for the electrical supply of the voltage measuring element, of the information processing unit and of the radio transceiver. 20 Alternatively, the primary module 60 comprises an infrared transceiver when the data links connecting the primary module to the secondary modules are infrared links. Alternatively, the primary module 60 comprises an optical transceiver when the data links connecting the primary module to the secondary modules are optical fibres. Alternatively encore, the primary module 60 comprises an electrical transceiver when 25 the data links connecting the primary module to the secondary modules are twisted pair or carrier current links or any other galvanically isolated links. The first secondary module 62A comprises, for each of the first 42A, second 44A and third 46A secondary conductors, a transducer 76A of the intensity of the current flowing in the corresponding secondary conductor 42A, 44A, 46A. The first secondary module 30 62A comprises an information processing unit 78A, a radio transceiver 80A, and a radio antenna 82A when the data link connecting the first secondary module to the primary module is a radio link. Alternatively, the first secondary module 62A comprises an infrared transceiver when the data link connecting the first secondary module to the primary module is an infrared 35 link. Alternatively, the first secondary module 62A comprises an optical transceiver 8 when the data link connecting the first secondary module to the primary module is an optical fibre. Alternatively further, the first secondary module 62A comprises an electrical transceiver when the data link connecting the first secondary module to the primary module is a twisted pair or a link via carrier current or any other galvanically 5 isolated link. The first secondary module 62A further comprises a supplying member 84A for electrical supplying the information processing unit and the radio transceiver. The first secondary module 62A is identified by a unique number, also called identifier. The other secondary modules 62B, ... , 62N are identical to the first secondary module 10 62A described previously, and comprise the same elements by replacing each time the letter A with the corresponding letter B, ..., N concerning the references of the elements. Each of the other secondary modules 62B, ... , 62N also has a unique identifier. The centralising module 64 comprises an information processing unit 86, a database 15 88 and a man-machine interface 90. The centralising module 64 comprises a radio transceiver 92, a radio antenna 94 and a supplying member 96 for supplying electricity to the information processing unit, the database, the man-machine interface and the radio transceiver. The voltage measuring element 66 is able to measure the first voltage Va of the first 20 primary conductor 34, the second voltage Vb of the second primary conductor 36 and the third voltage Vc of the third primary conductor 38. The voltage measuring element 66 is also able to measure the frequency Fotage of the three-phase voltage flowing through the primary conductors 34, 36, 38. The information processing unit 68 comprises a processor 98 and a memory 100 able 25 to store a first identifying application 101 for identifying the phase corresponding to each measured voltage Va, Vb, Vc. The memory 100 is able to store a first sampling software 102 for sampling, over the period Pitage of the voltage and with a predetermined sampling period Psamp, of the value of the measured voltage Va, Vb, Vc. The samples of the measured voltage Va, 30 Vb, Vc are denoted respectively Vam, Vbm, Vcm where m is an index of samples varying between 1 and N 5 zmp, Namp being an integer representing the number of voltage samples over the voltage period Paiage corresponding to a sampling frequency Fsamp. Nsamp is also called number of samples. The memory 100 is able to store an associating software 103 for associating in a 35 predetermined manner the first measured voltage Va with the first phase, in such a way 9 that the measured voltage Va is considered equal to V1. The memory 100 is able to store a first determining software 104 for determining K coefficient of a transform of samples Vam, Vbm, Vcm of each measured voltage, K being an integer greater than or equal to 1. 5 The transform is, for example, a Fourier transform, and the first determining software 104 is able to calculate K coefficient(s) Re k(Vj), imk(Vj) of the Fourier series decomposition of the samples Vam, Vbm, Vcm of each measured voltage Va, Vb, Vc, with k between 1 and K, and j respectively equal to a, b and c. The coefficients Rek(Vj) and Im k(Vj) satisfy the following equation, k being between 10 1 and K: Nsanp Re-k(Vj) = ZV x cos(2xI xFI., x k x m x T) (1) Np Im k(Vj)= Vjm x sin(2x 1-I xF x k x m x T) (2) rn=I 15 where T represents the sampling period, also denoted as Psamp. The first coefficients Re_1(Vj) and Im_1 (Vj) are also called harmonic coefficients and correspond respectively to the X-axis and to the Y-axis of the Fresnel vector of the corresponding measured voltage Vj. The first determining software 104 thus forms a software for determining the Fresnel 20 vector of each of the three measured voltages. In what follows, the notations Va, Vb, Vc, V1, V2, V3 are used indifferently for the corresponding voltage and for the Fresnel vector associated to this voltage. The memory 100 is also able to store a first calculation software 105 for calculating an image vector Ph 1(Vj) via a first rotation of the Fresnel vector of a voltage among the 25 two measured voltages Vb, Vc other than the first measured voltage Va, j being equal to b or c. The image vector Phei (Vj) calculated using the first calculation software 105 then satisfies the following equation: PhOl(Vj)= [cos(01)x Re(Vj)- sin(O1)x Im(Vj)]+i x [cos(O1)x Im(Vj)+sin(O1)x Re(Vj)] 30 (3) The memory 100 is also able to store a first comparison software 106 for comparing each image vector Phe1 (Vj) with the Fresnel vector of the first measured voltage Va.

10 The first determining software 104, the first calculation software 105, and the first comparison software 106 form the first identifying application 101, the first identifying application 101 being able to identify the phase corresponding to each of the two other measured voltages, with the first measured voltage being associated to the first phase 5 in a predetermined manner by the associating software 103. The memory 100 is able to store an emission software 107 for emitting a first message M1 to each secondary module 62A, ... 62N and for the centralising module 64, and a distributing software 108 for distributing a unique token to the secondary modules 62A, ... 62N successively. 10 The memory 100 is also able to store a first indicating software 109 for indicating end of identification, able to emit a first signal, such as a first lighted signal, when the first identifying application 101 identified the phase corresponding to each of the measured voltages. The first message M1 contains in particular a signal allowing for the time 15 synchronisation of the samples of the measured intensity via a corresponding current sensor 76A, ...76N in relation to the samples of the measured voltage, the sampling period Psamp and the coefficients Re-k(Vj), lm_k(Vj) of the Fourier series decompositions of the three voltages Va, Vb, Vc until the harmonic K, calculated using the first determining software 104. 20 Two possible methods of synchronisation between the primary module and the secondary modules are described in patent applications FR 11 57170 and respectively FR 12 54796, filed on 4 August 2011 and respectively on 24 May 2012 by the applicant of this applicant. This synchronisation allows for the calculation of the electrical energy of the current flowing in the corresponding secondary conductor 42A, 44A, 46A. 25 The first message M1 also contains the identifier of the secondary module which shall be authorised to emit its second message to the centralising module 64 after the receiving of the first message M1. The identifier of the secondary module authorised to emit its measurement information is determined using the distributing software 108, with the identifier of the module contained in the first message M1 making it possible to 30 designate the secondary module to which the unique token has been assigned. The radio transceiver 70 is compliant with the ZigBee communication protocol based on the standard IEEE-802.15.4. Alternatively, the radio transceiver 70 is compliant with the standard IEEE-802.15.1, also called Bluetooth standard, or with the standard IEEE 802.15.2. Alternatively further, the radio transceiver 70 is compliant with the standard 35 IEEE-802-11 also called WiFi standard, or any other proprietary radio protocol.

11 The radio antenna 72 is adapted to emit radio signals to the antennas 82A, ..., 82N of the secondary modules and of the antenna 94 of the centralising module, and also for receiving radio signals from said antennas 82A, ... , 82N, 94. In other words, the primary module 60 is connected to each of the secondary modules 62A, ..., 62N and to 5 the centralising module 64 by a corresponding radio link. The supplying member 74 is able to electrically supply the voltage measuring element 66, the information processing unit 68 and the radio transceiver 70 using the three phase voltage flowing through the primary conductors 34, 36, 38. Each intensity sensor 76A of the first secondary module 62A is able to measure a 10 respective intensity among a first intensity 11A flowing in the first output secondary conductor 42A, a second intensity 12A flowing in the second output secondary conductor 44A and a third intensity 13A flowing in the third output secondary conductor 46A. Each intensity sensor 76A, also called current sensor, comprises a first coil 110A 15 arranged around the corresponding secondary output conductor 42A, 44A, 46A and a first winding 112A arranged around the first coil, as shown in figure 3. The flowing of the current through the corresponding secondary output conductor is able to generate an induced current proportional to the intensity of the current in the first winding 11 2A. The first coil 11OA is a Rogowski coil. The first coil 11 0A is more preferably an opening 20 coil in order to facilitate its arranging around the corresponding conductors. For each current sensor 76A, the flowing of the current through the corresponding secondary output conductor is able to generate a signal proportional to the intensity of the current in the first winding 1 12A. The information processing unit 78A visible in figure 2, comprises a data processor 25 114A, and a memory 116A associated to the data processor and able to store a second sampling software 118A for sampling, over the voltage period Poiage, of the values of the first, second and third intensities IxA, lyA, IzA measured. For reasons of simplification, the intensities IxA, lyA, IzA are denoted in what follows by lx, ly, lz. The memory 116A is able to store a reception software 119A for receiving the first 30 message M1, a synchronising software 120A for the time synchronisation of each current sensor 76A in relation to the voltage measuring element 66. The memory 116A is able to store a second determining software 121A for determining K coefficients of the transform of the samples Ixm, lym, lzm of each measured intensity, K being greater than or equal to 1. In the described embodiment, the transform is the Fourier transform, 35 and the second determining software 121A is able to calculate K coefficients Re-k(lj), 12 lm_k(lj) of the Fourier series decomposition of the samples lxm, lym, lzm of each measured intensity Ix, ly, lz, with k between 1 and K and j respectively equal to x, y and z. The coefficients Rek(lj) and Imk(lj) satisfy the following equation, k being between 1 5 and K: Nn Re k(Ij) = Ijm x cos(2 x I x F, x k x m x T) (4) mn=1 N nimk(Ij)= Ijm x sin(2x IF xkx m x T) (5) 10 where T represents the sampling period, also denoted as Psamp. The first coefficients Re_1(lj) and Im_1(lj) are also called harmonic coefficients and correspond respectively to the X-axis and to the Y-axis of the Fresnel vector of the corresponding measured intensity Vj. The second determining software 121A thus forms a software for determining the 15 Fresnel vector of each of the three measured intensities. In what follows, the notations Ix, ly, lz, 11, 12, 13 are used indifferently for the corresponding intensity and for the Fresnel vector associated to this intensity. The memory 116A is able to store a second calculation software 122A for calculating three image vectors Ph_62(lj) via a second rotation of the Fresnel vectors of the three 20 measured intensities lx, ly, Iz, j being equal to x, y and z. The image vectors Ph_62(lj) calculated using the second calculation software 122A then satisfy the following equation: PhO02(Ij)= [cos(62) x Re(Ij)- sin(02) x Im(Ij)]+ i x [cos(02) x In(Ij) + sin(02) x Re(Ij)] 25 (6) The memory 116A is also able to store a second comparison software 124A for comparing, with a predetermined interval of angular values, the value of the angle between each image vector Ph_02(lj) and a reference axis X visible in figure 4. 30 The second determining software 121A, the second calculation software 122A, and the second comparison software 124A form a second identifying application 125A for identifying the phase corresponding to each of the three measured intensities lx, ly, iz.

13 The memory 11 6A is also able to store a second indicating software 126A for indicating the end of identification, able to emit a second signal, such as a second light signal, when the second identifying application 125A identified the phase corresponding to each of the measured intensities. 5 The memory 116A is able to store a calculation software 127A for calculating the electrical energy E 1 +, E 1 -, E 2 +, E 2 -, E 3 +, E 3 - of the current flowing in the corresponding secondary conductor 42A, 44A, 46A and an emission software 128A for emitting a second message M2A to the centralising module 64. The second message M2A contains the identifier of the first secondary module 62A, 10 the values of active energies E 1 +, E 1 -, E 2 +, E 2 -, E 3 +, E 3 - for all of the three phases of the three-phase voltage calculated by the calculation software 123A. The radio transceiver 80A is of the same type as the radio transceiver 70. The radio antenna 82A, of the same type as the radio antenna 72, is adapted to receive radio signals from the antenna 72 of the primary module and from the antenna 15 94 of the centralising module and also to emit radio signals to the antennas 72, 94. The supplying member 84A, visible in figure 3, is able to supply the information processing unit 78A and the radio transceiver 80A. The supplying member 84A comprises, for each of the first 42A, second 44A and third 46A secondary conductors, a second coil 130A arranged around the corresponding secondary conductor 42A, 44A, 20 46A and a second winding 132A arranged around the second coil. The flowing of the current in the corresponding secondary conductor 42A, 44A, 46A is able to generate an induced current in the second winding 132A. The supplying member 84A comprises a convertor 134A connected to each of the second windings 132A and able to deliver a predetermined voltage to the information 25 processing unit 78A and to the radio transceiver 80A. Each second coil 130A is an iron coil. Each second coil 130A is more preferably an opening coil in order to facilitate its arranging around the corresponding conductors. In other words, the secondary module 62A is self-powered by the intermediary of the supplying member 84A comprising the second coils 130A adapted to recover the 30 magnetic energy coming from the flowing of the current in the corresponding secondary conductors 42A, 44A, 46A. The elements of the other secondary modules 62B, ... , 62N, and respectively the second messages M2B, ..., M2N, are identical to the elements of the first secondary module 62A, and respectively to the second message M2A, described previously, and 14 comprise the same sub-elements by replacing each time the letter A with the corresponding letter B, ..., N concerning the references of the sub-elements. The information processing unit 86 of the centralising module, visible in figure 2, comprises a data processor 136, and a memory 138 associated to the processor and 5 able to store a reception software 140 for receiving the first and second messages M1, M2A,..., M2N, a recording software 142 for recording in the database 88 information contained in the messages M1, M2A,..., M2N received. The memory 138 is able to store a processing software 144 for processing said information received, a displaying software 146 for displaying data and a transmission software 148 for transmitting data 10 to a remote server, not shown. The man-machine interface 90 comprises a display screen and a keyboard, not shown. Alternatively, the man-machine interface 90 comprises a touch-sensitive screen and the key-entry of data is carried out by the intermediary of touch-sensitive keys displayed on the screen. Alternatively, the man-machine interface is moved to a mobile 15 telephone, a tablet computer or a portable computer via a radio link, such as a link compliant with the WiFi standard, a link compliant with the Bluetooth standard, a near field link, also called Near Field Communication (NFC), or a radio-identification link, also called Radio Frequency IDentification (RFID) link. The radio transceiver 92 is of the same type as the radio transceivers 70, 80A, ..., 80N. 20 The radio antenna 94, of the same type as the radio antennas 72, 82A, ... , 82N, is able to receive radio signals coming from the antenna 72 of the primary module and from the antennas 82A, ..., 82N of the secondary modules and also to emit radio signals to said antennas 72, 82A, ... , 82N. The operation of the measuring system 20 shall now be explained using figures 5 and 25 6. The steps, visible in figure 5, of the measuring method implemented by the primary module 60 for the identification of the phase corresponding to each of the three measured voltages Va, Vb, Vc shall now be described. During the first step 150, the primary module 60 is initialised and measures the 30 frequency Fge. of the three-phase voltage of the primary conductors 34, 36, 38. The frequency Fvitage of the three-phase voltage is equal to the frequency of the network, such as 50 Hz for example in Europe and 60 Hz for example in the United States. During this first step 150, the primary module 60 then measures the first, second and third voltages Va, Vb, Vc using its voltage measuring element 66 and samples the 35 measured values of the voltages Va, Vb, Vc using its first sampling software 102.

15 The sampling frequency Fsamp is a multiple of the frequency Fitage of the three-phase voltage equal to the inverse of the period Peag. of said three-phase measured voltage previously. The period PwItage of the three-phase voltage is equal to the period of the network, i.e. about 20ms in Europe and about 16.66 ms in the United States. 5 In the described embodiment, the sampling frequency Fsamp has, for example, a value equal to 7200 Hz and the number of samples Nsamp per period of 20 ms is then equal to 144. During the step 150, in order to optimise the precision of the measuring of the energy, the period Peng of the voltage is measured regularly, such as every ten seconds, in 10 order to take into account variations over time of the latter. During the following step 155, the associating software 103 associates in a predetermined manner the first measured voltage Va with the first phase. In other words, the first measured voltage Va is assumed to be equal to the voltage V1. The first determining software 104 then determines, during the following step 160, the 15 first coefficient or coefficients Rek(Vj) and Imk(Vj) of each of the measured voltages Va, Vb, Vc using equations (1) and (2), where j is equal to a, b, or c and k is between 1 and K. During this step 160, the first calculation software 105 calculates, using the equation (3), the image vector Ph01 (Vj) via the first rotation of the Fresnel vector of one among 20 the two other measured voltages, where 61 designates the angle of the first rotation. By associating an index kp to each phase to be identified, the index k, being an integer equal to 1 for the first phase and taking the integer values equal to 2 or 3 for the two other phases, the value of the angle 61 of the first rotation depends on the index kp of the phase to be identified. 25 The value, expressed in degrees, of the angle 61 of the first rotation is, for example, defined by the following equation: 01 = (k, -1t) x 120" (7) 30 The first identifying device 101 first seeks to identify the measured voltage corresponding to the second phase, the measured voltage corresponding to the third phase then being identified by deduction. The first calculation software 105 then calculates the image vector Ph_1 20(Vj) via the first rotation of the Fresnel vector from one among the two other measured voltages, such as the image vector corresponding 16 to the second measured voltage Vb. The index k. associated to the second phase to be identified is equal to 2, and the angle 81 of the first rotation is then equal to 1200. After the 120' rotation of the Fresnel vector Vb of the second measured voltage, the first comparison software 106 compares the image vector Ph 120(Vb) obtained with 5 the Fresnel vector V1 of the first measured voltage. The comparison consists, for example, in comparing the first coefficients of the Fourier series decomposition of the image vector Ph_120(Vb) with the first corresponding coefficients of the Fresnel vector VI of the first measured voltage according to the following inequalities: 10 Rel(Vi) - C1 x Mod(VL) < Re_ 1(Ph_120(Vb)) < Rel(V1) + C1 x Mod(V) (8) Iml(VL) - C1x Mod(Vl) < Im_ 1(Ph_120(Vb)) < Im_1(V1)+ C1 x Mod(V1) (9) where C1 is a first factor, and Mod(V1) represents the module of the Fresnel vector V1 of the first measured voltage. 15 According to the inequalities (8) and (9), the comparison between the image vector Ph_1 20(Vb) and the Fresnel vector V1 of the first measured voltage is carried out with a first error tolerance equal to C1 times the module of the Fresnel vector of the first measured voltage V1 both on the X-axis and on the Y-axis. In the described embodiment, the first factor C1 is equal to 0.1, the first error tolerance 20 corresponds to a first angular tolerance of about +/- 60 to +/-8*. If the inequalities (8) and (9) are respected, i.e. if the 120" rotation of the Fresnel vector Ph_120(Vb) of the second measured voltage is substantially confounded with the Fresnel vector V1 of the first measured voltage, then the first comparison software 106 considers during the step 165 that the second measured voltage Vb corresponds to the 25 second phase, and by deduction that the third measured voltage Vc corresponds to the third phase. In other words, Vb is equal to V2 and Vc is equal to V3. The first indicating software 109 finally signals during the step 170 the correct locating of the voltage probes by emitting a first signal, such as a first lighted signal using light emitting diodes, not shown, in order to indicate that the first identifying application 101 30 identified the phase corresponding to each of the measured voltages Va, Vb, Vc. If, during the step 160, the result of the comparison according to the inequalities (8) and (9), between the image vector Ph_120(Vb) of Vb by 1200 rotation and the Fresnel vector V1 of the first measured voltage is negative, then the first calculation software 105 calculates, in a similar manner, during the step 175, the image vector Ph_120(Vc) 35 via the first 1200 rotation of the Fresnel vector Vc of the third measured voltage, and 17 the first comparison software 106 compares in a similar manner the image vector obtained Ph_120(Vc) with the Fresnel vector V1 of the first measured voltage according to the following inequalities: 5 Re 1(Vl) - Cl x Mod(V1) < Re 1(Ph_120(Vc)) < Re l(V1)+ Cl x Mod(V1)(10) Im_1(V1) - C1 x Mod(V1) < Im 1(Ph.120(Vc)) < Im_1(V1)+ C x Mod(V1)(11) If the result of the comparison is positive, i.e. if the 120* rotation of the Fresnel vector Vc of the third measured voltage is equal to, to the nearest first error tolerance, the 10 Fresnel vector V1 of the first measured voltage, then the first comparison software 106 considers, during the step 180, that the third measured voltage Vc corresponds to the second phase, and by deduction, that the second measured voltage Vb corresponds to the third phase. In other words, Vc is equal to 2 and Vb is equal to V3. At the end of the step 180, the method passes, in a similar manner, to the step 170, so 15 that the first indicating software 109 signals the correct locating of all of the voltage probes, i.e. that the first identifying application 101 identified the phase corresponding to each of the measured voltages Va, Vb, Vc. If the result of the comparison carried out during the step 175 is negative, then the method returns to the step 150. 20 This is also able to occur in the case of a relatively substantial phase shifting between the various measured voltages Va, Vb, Vc, in such a way that after rotation of the Fresnel vector by one of the other measured voltages Vb, Vc, the image vector obtained Ph_120(Vb), Ph _120(Vc) is not equal, to the nearest first error tolerance, to the Fresnel vector V1 of the first measured voltage. This is also able to occur in the 25 event of a substantial difference in the amplitudes of the voltages Va, Vb and Vc. The primary module 60 emits periodically the first message M1 to each of the secondary modules 62A, ... 62N and of the centralising module 64. The emission period Pemisson is predetermined, and more preferably equal to 1 second. The first message M1 is as such emitted every second. 30 After the emission of the first message M1, the primary module 60 again measures the voltage Va, Vb, Vc of the primary conductors 34, 36, 38. The steps, visible in figure 6, of the measuring method implemented by the secondary modules 62A, ...62N for the identification of the phase corresponding to each of the three measured intensities Ix, ly, lz shall now be described for the first secondary 35 module 62A.

18 During the step 200, the first secondary module 62A is initialised and opens sliding window for receiving the first message M1 using its reception software 119A. The receiving window is a window having a duration of a few tens of milliseconds that the first secondary module 62A slides over time. 5 During the receiving of the first message M1, the first secondary module 62A verifies that the first message M1 contains the synchronisation signal and the synchronising software 120A then initialises, on the date of reception of the first message M1, a counter intended to be incremented until a value corresponding to the emission period of the first message Pemission. The secondary module 62A then automatically returns to 10 the step of receiving 200 about one millisecond before the expected reception of the next first message M1. The synchronising software 120A also carries out the resynchronisation of the sampling using the value of the sampling period Psamp contained in the first message M1 and the date of reception of the first message M1. The date of reception of the first message M1 is the reference date for the 15 synchronisation of the first secondary module 62A in relation to primary module 60, and more precisely for the synchronisation of the measurement of the intensities IxA, lyA, IzA, denoted in what follows by lx, ly, Iz, in relation to the measurement of the voltages Va, Vb, Vc. If the first message M1 is not detected by the first secondary module 62A, the receiving 20 window is closed and no synchronisation is carried out. The first secondary module 62A then measures, during this step 200 and by the intermediary of its current sensors 76A, each of the first, second and third intensities Ix, ly, Iz. The second sampling software 11 8A samples furthermore the measured values of the three intensities Ix, ly, Iz, with the instant of the beginning of the sampling having 25 been reinitialised previously in order to provide the time synchronisation of the intensity sensor 76A in relation to the voltage measuring element 66. During the step 210, the second determining software 121A begins by determining, using the equations (4) and (5), the first coefficient or coefficients Rek(Ij) and Im-k(lj) of each of the measured intensities Ix, ly, Iz, where j is equal to x, y, z, and k is 30 between 1 and K. The second calculation software 122A then determines a phase shifting R of the first measured voltage V1, i.e. the angle between the Fresnel vector V1 of the first measured voltage and the reference axis X, using the following equations: 19 If Re 1(V1)>0, then R = arctan ImI(V1) (12) (Re1(V1) If Rel (V1)<0, then]R =1800 + arctan - (13) Re 1(V1)) During the steps 220 to 260, the second calculation software 122A successively 5 calculates the image vectors Ph_92(lj) via the second rotation of the Fresnel vectors of the measured intensities using the equation (6), where 82 designates the angle of the second rotation. The value of the angle 82 of the second rotation depends on the index kp of the phase to be identified. The value, expressed in degrees, of the angle 62 of the second rotation is, for example, 10 defined by the following equation: 02 = (k, -1I)x 120* - R with k, equal to 1, 2 or 3 (14) The second identifying application 125A first seeks, during the steps 220 and 230, to 15 identify the measured intensity corresponding to the first phase. The second calculation software 122A then calculates an image vector PhS(lj) via the second rotation of the Fresnel vector of the measured intensity lj, such as the image vector PhS(Ix) corresponding to the first measured intensity lx, where S is equal to -R. The index kP associated to the first phase to be identified is equal to 1, and the angle 82 of the 20 second rotation is then equal to -R, or S. After the S rotation of the Fresnel vector lj of the measured intensity, the second comparison software 124A compares the angle between the image vector PhS(lj) obtained and the reference axis X with a predetermined interval of angular values between a first negative value -al ref and a second positive value a2,ef. The comparison 25 consists, for example, in comparing the values of the tangents of these different angles according to the following inequality: Im 1(Ph S(Ij)) - tan(al f) < - - < tan(a 2 f) (15) Re- (PhS(Lj)) 30 In the example embodiment of figure 6, the first negative value -a1,lr is equal to -30* and the second positive value a 2 ref is equal to +300.

20 If the inequality (15) is satisfied by the first measured intensity ix, i.e. for j equal to x, then the second comparison software 124A considers during the step 230 that the first measured intensity corresponds to the first phase, i.e. that lx is equal to 11, and passes to the step 240. 5 Otherwise, the second calculation software 122A continues the step 220 by calculating the image vector PhS(ly) corresponding to the second measured intensity ly, then compares, in a similar manner using the inequality (15), the angle between the image vector PhS(ly) and the reference axis X with the predetermined interval of angular values ]-al ref; a 2 reff. 10 If the inequality (15) is satisfied by the second measured intensity ly, then the second comparison software 124A considers during the step 230 that the second measured intensity corresponds to the first phase, i.e. that ly is equal to 11, and passes to the step 240. Otherwise, the second calculation software 122A continues the step 220 by calculating 15 the image vector PhS(lz) corresponding to the third measured intensity lz, then compares, in a similar manner using the inequality (15), the angle between the image vector PhS(lz) and the reference axis X with the predetermined interval of the angular values ]-alref; a 2 ref[. If the inequality (15) is satisfied by the third measured intensity Iz, then the second 20 comparison software 124A considers during the step 230 that the third measured intensity corresponds to the first phase, i.e. that Iz is equal to 11, and passes to the step 240. Otherwise, the second calculation software 122A also passes to the step 240 given that the identification with the first phase has been tested for all of the measured 25 intensities ix, ly, Iz. The second identifying application 125A then seeks, during the steps 240 and 250, to identify in a similar manner the measured intensity corresponding to the second phase. The second calculation software 122A then calculates an image vector Ph_1 20(PhS(lj)) via the second rotation of the Fresnel vector of the measured 30 intensity lj, successively for the first, second and third measured intensities Ix, ly, lz, until the moment when the measured intensity corresponding to the second phase has been identified or until having tested all of the measured intensities Ix, ly, Iz. The index kp associated to the second phase to be identified is equal to 2, and the angle 82 of the second rotation is then equal to 120*-R, or 120*+S. Those skilled in the 35 art will note that Ph_120(PhS(lj)) is equal to Ph_(1 20+S)(lj).

21 After each 120*+S rotation of the Fresnel vector of the measured intensity Ij, the second comparison software 124A compares the angle between the image vector Ph_120(PhS(j)) obtained and the reference axis X with the predetermined interval of angular values ]-alref; a 2 ref[. 5 The comparison consists, for example, in comparing the values of the tangents of these different angles according to the following inequality: -tanalre)Im 1(Phl120(Ph S(Jj))) - tan(al<)< - - - <tan(a 2 ,) (16) Re_1(Ph120(Ph S(Ij))) 10 If the inequality (16) is satisfied by said measured intensity lj, then the second comparison software 124A considers during the step 250 that said measured intensity lj corresponds to the second phase, i.e. that lj is equal to 12, and passes to the step 260. Otherwise, the second calculation software 122A continues the step 240 by calculating 15 the image vector Ph_120(PhS(lj)) corresponding to the following measured intensity, then compares, in a similar manner using the inequality (16), the angle between the image vector Ph_120(PhS(lj)) and the reference axis X, with the predetermined interval of angular values ]-al re; a 2 ,e[. If the inequality (16) is satisfied by the third measured intensity Iz, then the second 20 comparison software 124A considers during the step 250 that the third measured intensity corresponds to the second phase, i.e. that lz is equal to 12, and passes to the step 260. Otherwise, the second calculation software 122A also passes to the step 260 given that the identification with the second phase has been tested for all of the measured 25 intensities Ix, ly, iz. The second identifying application 125A finally seeks, during the steps 260 and 270, to identify in a similar manner the measured intensity corresponding to the third phase. The second calculation software 122A then calculates an image vector Ph_120(Ph_120(PhS(j))) via the second rotation of the Fresnel vector of the 30 measured intensity lj, successively for the first, second and third measured intensities Ix, ly, Iz, until the moment when the measured intensity corresponding to the third phase has been identified or until having tested all of the measured intensities lx, ly, Iz.

22 The index k, associated to the third phase to be identified is equal to 3, and the angle 02 of the second rotation is then equal to 240 0 -R, or 240*+S. Those skilled in the art will note that Ph_120(Ph_120(PhS(lj))) is equal to Ph_(240+S)(lj). After each 240 0 +S rotation of the Fresnel vector of the measured intensity lj, the 5 second comparison software 124A compares the angle between the image vector Ph_120(Ph_120(PhS(j))) obtained and the reference axis X with the predetermined interval of angular values ]-allre; a 2 ret[. The comparison consists, for example, in comparing the values of the tangents of these different angles according to the following inequality: 10 - tan(alj) m Iml(Ph 120(Ph 120(PhS(Ij)))) Re_1(Ph_120(Ph_120(PhS(Ij)))) If the inequality (17) is satisfied by said measured intensity lj, then the second comparison software 124A considers during the step 270 that said measured intensity 15 lj corresponds to the third phase, i.e. that lj is equal to 13, and passes to the step 275. Otherwise, the second calculation software 122A continues the step 260 by calculating the image vector Ph_120(Ph_120(PhS(lj))) corresponding to the following measured intensity, then compares, in a similar manner using the inequality (17), the angle between the image vector Ph_120(Ph_120(PhS(j))) and the reference axis X, with 20 the predetermined interval of angular values ]-al ref; a2,e 2 [. If the inequality (17) is satisfied by the third measured intensity Iz, then the second comparison software 124A considers during the step 270 that the third measured intensity corresponds to the third phase, i.e. that lz is equal to 13, and passes to the step 275. 25 Otherwise, the second calculation software 122A also passes to the step 275 given that the identification with the third phase has been tested for all of the measured intensities Ix, ly, Iz. The second identifying application 125A tests, during the step 275, if all of the measured intensities ix, ly, lz have been identified at a respective phase, and where 30 applicable passes to the step 280. During the step 280, the second indicating software 126A signals the correct locating of the current sensors 76A by emitting a second signal, such as a second lighted signal using light-emitting diodes, not shown, in order to indicate that the second identifying 23 application 125A identified the phase corresponding to each of the measured intensities lx, ly, lz. Each current sensor 76A comprises, for example, a light-emitting diode, not shown, and the second lighted signal is in the form of a diode flash for the first phase, in the 5 form of two flashes for the second phase and three flashes for the third phase. If all of the measured intensities Ix, ly, lz have not been identified at a respective phase, then the second identifying application 125A tests, during the step 285, if at least two measured intensities Ix, ly, lz have been identified at a respective phase, and where applicable passes to the step 290. Otherwise, the second identifying application 10 125A returns to the step 200. During the step 290, the second identifying application 125A identifies through deduction the phase corresponding to the measured intensity which has not been identified, knowing that the phases have been identified for all of the other measured intensities. It then passes to the step 280, so that the correct locating of current 15 sensors 76A is signalled. After identification of the phases, the calculation software 127A also calculates periodically the active energy E-, E2+, E 2 -, E 3 +, E 3 - for each of the three phases using the values of the voltages V1, V2, V3 measured and identified, as well as values of the intensities 11A, 12A, 13A measured by the current sensors 76A and identified. The 20 period for calculating active energies E 1 , E2, E 3 is equal to the period PItage, i.e. for example 20 ms. The variations of the voltages V1, V2, V3 are sufficiently limited between two instants of emission of the first message M1, i.e. over a period of one second, in order to enable the calculation of the active energies E-, E 2 +, E 2 -, E 3 +, E 3 - every 20 ms, using the 25 values of the intensities 11A, 12A, 13A measured every 20 ms and values of the voltages V1, V2, V3 received every second. Pour the calculation of the active energies E-, E 2 +, E 2 -, E 3 +, E3-, the calculation software 127A calculates, at each period Py:tage, an active power Pj of each phase number j, j being equal to 1, 2 or 3, using the following equations: 30 , = [Rek(V)x Rek(IjA)+ Imk(Vj) xImk(IjA)] (18) 2 where k is between I and K 24 K j = p,(19) k=1 The calculation software 127A also determines, at each period Pitage, the reactive power Qj of each phase number j, j being equal to 1, 2 or 3, using the following 5 equations: - [Im k(Vj)x Re k(IjA) - Re k(Vj) x Irnk(IjA)] (20) 2 where k is between 1 and K 10 K Q2 IZ(v.~ (21) k=1 A each period Pvoltage, a first active energy Ej+ is incremented solely when P, 1 is positive, i.e. when the power corresponding to the product of the fundamental current 15 and of the fundamental voltage is positive, which corresponds to a power consumed by a charge downstream of the measuring system. An increment of the first active energy AEj+ is then equal to the product of the period Pvoitage with the active power Pj, calculated over the last period, according to the following equation: 20 AEj = Pornage x Pj, 1 with P 1 > 0 (22) At each period PItage, a second active energy Ej- is incremented solely when P,1 is negative, i.e. when the power corresponding to the product of the fundamental current 25 and of the fundamental voltage is negative, which corresponds to a power supplied by a generator downstream of the measuring system. An increment of the second active energy AEj- is then equal to the product of the period Potage with the active power P 1 calculated over the last period, according to the following equation: 30 AEj =Po,,ge x P, with P < 0 (23) For a three-phase electrical network, the measuring system 20 thus constantly increments six energy counters: E 1 , E 1 -, E 2 +, E 2 -, E 3 +, E 3 -. As such the energies produced and consumed are indeed separate. The measuring system 20 is also 5 adapted to measure the energy supplied by energy generators distributed over the electrical network. The first secondary module 62A thus elaborates its second message M2A. The second message M2A contains the identifier of the first secondary module 62A, the values of the six energy counters E 14 , E 1 -, E 2 +, E 2 -, E 3 +, E 3 - for all of the three phases of the 10 three-phase voltage and the complex coefficients Re k(ljA), Imk(ljA) of the Fourier series decomposition of the three currents 11A, 12A, 13A until the harmonic K. In addition, the second message M2A contains the values of the root mean squares, also denoted as RMS, of the currents 11A, 12A, 13A of the three phases, as well as the terms P 1

,

1 and Qj for each of the three phases, and the values Pj and Q for each of the 15 three phases. In the hypothesis where the identifier of the first secondary module 62A as contained in the first message M1 received previously, the first secondary module 62A then emits its second message M2A using its emission software 128A. Otherwise, the first secondary module 62A directly returns to the step for receiving the first message M1, and will emit 20 its second message M2A when the first message M1 contains its identifier then indicating that the unique token has been assigned to it in order to authorise it to emit its second message M2A. The steps of the method of measuring implemented by the other secondary modules 62B, ..., 62N are identical to the steps 200 to 290 described previously for the first 25 secondary module 62A, and are carried out furthermore simultaneously between all of the secondary modules 62A, ..., 62N via the time synchronisation carried out using the first message M1. The centralising module 64 receives, using its reception software 140, the first message M1 of the primary module 60 and the second message of the secondary 30 module authorised to emit according to the distributed token mechanism, for example the message M2A. The centralising module 64 then records in its database 88 the values received and contained in the first message M1 and in the second message M2A, by the intermediary of its recording software 142. In addition, the processing software 144 35 carries out a time-date stamping of the recorded data.

26 In addition, the processing software 144 calculates certain electrical quantities, such as the power factor cos($F) for each of the three phases numbered j of the three-phase voltage. The quantities measured and calculated by the measuring system are then displayed 5 on the screen of the man-machine interface 90 of the centralising module by the intermediary of the displaying software 146. The centralising module 64 finally transmits, using its transmission software 148, these quantities measured and calculated to the remote server, not shown. The remote server is able to carry out a centralised management of the quantities measured and 10 calculated for each measuring system 20. The centralising module 64 is then prepared to receive the next first message M1 from the primary module and the second message from the secondary module authorised to emit the next time according to the distributed token mechanism, for example the message M2A. 15 The measuring system 20 according to the invention is as such particularly simple to implement since it suffices to connect the voltage measuring element 66 to each of the primary conductors 34, 36, 38 without having to worry about knowing to which phase corresponds each of the primary conductors 34, 36, 38. The method of measuring according to the invention identifies indeed, automatically and without human 20 intervention, the phase corresponding to each of the measured voltages Va, Vb, Vc. Furthermore, the user is informed of the correct locating of the voltage probes via the emission of the first signal by the first indicating software 109, which further facilities the use of the measuring system 20. In addition, it is also sufficient to associate each current sensor 76A to a corresponding 25 secondary conductor 42A, 44A, 46A without having to worry about knowing to which phase corresponds each of the secondary conductors 42A, 44A, 46A. The method of measuring according to the invention identifies indeed also automatically the phase corresponding to each of the measured intensities lx, ly, Iz. This is particularly adapted to the current sensors 76A in the shape of a clamp which 30 are able to be removed, then put back into place easily and frequently. This is also well adapted to the current sensors 76A in the shape of a flexible coil which can be opened for their assembly and disassembly. Furthermore, the user is also informed of the correct locating of the current sensors via the emission of the second signal by the second indicating software 126A, which 35 further facilitates the use of the measuring system 20. Each current sensor comprises a 27 viewing member for viewing this second signal, the viewing member being for example a light-emitting diode, which makes it possible for the user to know directly the phase to which each current sensor is associated. Those skilled in the art will understand that the second devices for identifying the phase 5 corresponding to each of the three measured intensities 125A, ..., 125N are not necessarily separate from the first identifying device the phase corresponding to each of the two other measured voltages 101, with the first device 101 and the second devices 125A, ... , 125N being able to form the same device. The figure 7 shows a second embodiment for which the elements similar to the first 10 embodiment, described previously, are marked with identical references, and are not described again. According to the second embodiment, the identification of the phase corresponding to each of the measured voltages Va, Vb, Vc is carried out in a manner identical to what has been described for the first embodiment, and the identification of the phase 15 corresponding to each of the measured intensities Ix, ly, Iz is carried out according to an alternative of what has been described for the first embodiment. The memory 116A is able to store, in place of the second comparison software 124A, a third comparison software, for each measured intensity lx, ly, lz, of the coordinates of the Fresnel vector lx, ly, lz of said measured intensity with the coordinates of the 20 Fresnel vector V1, V2, V3 of a respective measured and identified voltage. The second determining software 121A, the second calculation software 122A, and the third comparison software thus form the second identifying application 125A. The steps, visible in figure 7, of the measuring method implemented by the secondary modules 62A, ... 62N for the identifying, according to the second embodiment, of the 25 phase corresponding to each of the three measured intensities lx, ly, Iz shall now be described for the first secondary module 62A. The initial step 300 is identical to the step 200 described previously for the first embodiment. The first secondary module 62A in particular measures, during this step 300 and by the 30 intermediary of its current sensors 76A, each of the first, second and third intensities lx, ly, Iz, and the second sampling software 118A samples the measured values of the three intensities Ix, ly, lz, with the instant of the beginning of the sampling having been reinitialised previously in order to provide for the time synchronisation of the intensity sensor 76A in relation to the voltage measuring element 66.

28 During the step 310, the second determining software 121A begins by determining the first coefficient or coefficients Re k(lj) and Im k(Ij) of each of the measured intensities Ix, ly, Iz, using the equations (4) and (5), where j is equal to x, y, z, and k is between 1 and K. 5 The second calculation software 122A then normalises the measured intensities Ix, ly, lz in order to obtain normalised intensities Jx, Jy, Jz according to the following equations: Re- (Jj)= Rel (Ij) x Mod(V1) (24) Mod(Ij) 10 Im 1(Jj) = Im I(Ij) Mod(VI) (25) - - Mod(Ij) where j is respectively equal to x, y and z. At the end of this normalisation of the measured intensities, the module of the Fresnel vectors of the normalised intensities Jx, Jy, Jz is then equal to the module of 15 the Fresnel vector V1 of the first measured voltage. During the steps 320 to 360, the third comparison software successively compares the Fresnel vectors of each of the normalised intensities Jx, Jy, Jz with the Fresnel vectors V1, V2, V3 of each of the voltages associated respectively to the first, second and third phases. 20 The third comparison software begins, for example, by comparing the Fresnel vector of the first normalised intensity Jx with the Fresnel vectors V1, V2, V3 of each of the voltages during the step 320. The comparison consists, for example, in comparing the first coefficients of the Fourier series decomposition of the first normalised intensity Jx with the first corresponding 25 coefficients of the Fresnel vector Vj of the corresponding voltage according to the following inequalities: Re_1(Vj) - C2 x Mod(Vj) < Re_ 1(Jx) < Re_ 1(Vj) + C2 x Mod(Vj) (26) Im 1(Vj) - C2 x Mod(Vj) < Im 1(Jx) < Im l(Vj)+ C2 x Mod(Vj) (27) 30 where C2 is a second factor, j is equal to 1, 2 or 3, and Mod(Vj) represents the module of the Fresnel vector Vj of the corresponding voltage.

29 According to the inequalities (26) and (27), the comparison between the Fresnel vector of the first normalised intensity Jx and the Fresnel vector Vj of the corresponding voltage is carried out with a second error tolerance equal to C2 times the module of the Fresnel vector Vj of the corresponding voltage on both the X-axis and the Y-axis. 5 In the described embodiment, the second factor C2 is equal to 0.4, the second error tolerance corresponds to a second angular tolerance of approximately +/-25* to +/-35*. If the inequalities (26) and (27) are respected for the Fresnel vector V1 of the first voltage, then the third comparison software considers during the step 330 that the first measured intensity lx corresponds to the first phase, i.e. that Ix is equal to 11, and the 10 third comparison software passes to the step 340. Otherwise, the third comparison software continues the step 320 by comparing, in a similar manner using the inequalities (26) and (27), the Fresnel vector of the first normalised intensity Jx with the Fresnel vector Vj of the following voltage. If the inequalities (26) and (27) are respected for the Fresnel vector Vj, then the third 15 comparison software considers during the step 330 that the first measured intensity Ix corresponds to the phase associated to the Fresnel vector Vj for which the inequalities (26) and (27) are respected, i.e. that Ix is equal to lj. If the inequalities (26) and (27) are respected for the Fresnel vector V3 of the third voltage, then the third comparison software considers during the step 330 that the first 20 measured intensity Ix corresponds to the third phase, i.e. that lx is equal to 13, and passes to the step 340. Otherwise, the third comparison software also passes to the step 340 given that the identifying of the first measured intensity Ix has been tested for each of the phases. The second identifying application 125A then seeks, during the steps 340 and 350, to 25 identify in a similar manner the phase corresponding to the second measured intensity ly. The third comparison software then compares the Fresnel vector of the second normalised intensity Jy with the Fresnel vectors V1, V2, V3 of each of the voltages during the step 340, for example using the following inequalities: 30 Re (Vj) - C2 x Mod(Vj) < Re- (Jy) < Re (Vj) + C2 x Mod(Vj) (28) Im (Vj) - C2 x Mod(Vj)< Im (Jy) < Im (Vj) + C2 x Mod(Vj) (29) If the inequalities (28) and (29) are respected for the Fresnel vector V1 of the first 35 voltage, then the third comparison software considers during the step 350 that the 30 second measured intensity ly corresponds to the first phase, i.e. that ly is equal to 11, and the third comparison software passes to the step 360. Otherwise, the third comparison software continues the step 340 by comparing, in a similar manner using the inequalities (28) and (29), the Fresnel vector of the second 5 normalised intensity Jy with the Fresnel vector Vj of the following voltage. If the inequalities (28) and (29) are respected for the Fresnel vector Vj, then the third comparison software considers during the step 350 that the second measured intensity ly corresponds to the phase associated to the Fresnel vector Vj for which the inequalities (28) and (29) are respected, i.e. that ly is equal to Ij. 10 If the inequalities (28) and (29) are respected for the Fresnel vector V3 of the third voltage, then the third comparison software considers during the step 350 that the second measured intensity ly corresponds to the third phase, i.e. that ly is equal to 13, and passes to the step 360. Otherwise, the third comparison software also passes to the step 360 given that the 15 identifying of the second measured intensity ly has been tested for each of the phases. The second identifying application 125A finally seeks, during the steps 360 and 370, to identify in a similar manner the phase corresponding to the third measured intensity Iz. The third comparison software then compares the Fresnel vector of the third normalised intensity Jz with the Fresnel vectors V1, V2, V3 of each of the voltages 20 during the step 360, for example using the following inequalities: Re_1(Vj)- C2 x Mod(Vj)<Re1(Jz)< Re_1(Vj)+ C2 x Mod(Vj) (30) Im_1(Vj) - C2 x Mod(Vj) < Im_1(Jz) <Im 1(Vj)+ C2 xMod(Vj) (31) 25 In a similar manner to what has been described previously, if the inequalities (30) and (31) are respected for the Fresnel vector V1 of the first voltage, then the third comparison software considers during the step 370 that the third measured intensity Iz corresponds to the first phase, i.e. that lz is equal to 11, and passes to the step 375. Otherwise, the third comparison software continues the step 360 by comparing, in a 30 similar manner using the inequalities (30) and (31), the Fresnel vector of the third normalised intensity Jz with the Fresnel vector Vj of the following voltage. If the inequalities (30) and (31) are respected for the Fresnel vector Vj, then the third comparison software considers during the step 370 that the third measured intensity Iz corresponds to the phase associated to the Fresnel vector Vj for which the inequalities 35 (30) and (31) are respected, i.e. that lz is equal to lj, and passes to the step 375.

31 If the inequalities (28) and (29) are respected for none of the Fresnel vectors of the voltage, the third comparison software also passes to the step 375 given that the identification of the third measured intensity lz has been tested for each of the phases. The steps 375, 380, 385 and 390 are then identical respectively to the steps 275, 280, 5 285 and 290 described previously for the first embodiment. The transitions between the steps are also identical. If at least two measured intensities Ix, ly, lz have not been identified with a respective phase, the second identifying application 125A returns to the step 300. After identification of the phases, the calculation software 127A calculates, in the same 10 way and in a periodic manner, the active energy E1+, E-, E 2 +, E 2 -, E 3 +, E 3 - for each of the three phases using the values of the voltages V1, V2, V3 measured and identified, as well as the values of the intensities 11A, 12A, 13A measured by the current sensors 76A and identified. The first secondary module 62A then elaborates its second message M2A, and if it the 15 one that has the token, the sending then to the centralising module 64. The steps of the measuring method implemented by the other secondary modules 62B, 62N are identical to the steps 300 to 390 described previously for the first secondary module 62A, and are carried out furthermore simultaneously between all of the secondary modules 62A, ..., 62N through the time synchronisation carried out 20 using the first message M1. The centralising module 64 carries out the same processing as that described previously for the first embodiment. The operation of this second embodiment is moreover identical to that of the first described embodiment previously. 25 The advantages of this second embodiment are identical to those of the first described embodiment previously. It is as such conceived that the measuring system 20 according to the invention makes it possible to automatically identify the phase corresponding to each of the measured voltages, without the operator having to worry about knowing to which phase 30 corresponds each of the primary conductors 34, 36,38 during the connection of the voltage measuring element 66 to each of the primary conductors 34, 36, 38.

Claims (11)

1. A measuring system (20) for measuring at least one electrical quantity (Va, Vb, Vc) relative to a power installation (16), the installation (16) comprising electrical conductors (34, 36, 38) able to enable the flowing of a three-phase alternating current, the measuring system (20) comprising: 5 - a voltage measuring element (66) for measuring voltage of each of the electrical conductors (34, 36, 38), with each electrical conductor (34, 36, 38) being associated to a respective phase of the alternating network, - an information processing unit (68) able to receive the values of the measured voltages (Va, Vb, Vc), 10 - three current sensors (76A, ... , 76N), each current sensor (76A, .. , 76N) being able to measure the intensity of the current flowing in the corresponding electrical conductor (42A, ..., 46N), characterised in that the processing unit (68) comprises associating means (103) for associating in a predetermined manner the first measured voltage (Va) with a first 15 phase among the three phases, a first identifying device (101) for identifying the phase corresponding to each of the two other measured voltages (Vb, Vc) and a second identifying device (125A, ... , 125N) for identifying the phase corresponding to each of the three measured intensities (lx, ly, lz), and in that the second identifying device (125A, ... , 125N) comprises second determining 20 means (121A, ... , 121N) for determining the Fresnel vector (Ix, ly, lz) of each of the three measured intensities, second calculation means (122A, ... , 122N) for calculating three image vectors (Ph_02(j)) via a second rotation of the Fresnel vectors (Ix, ly, lz) of the three measured intensities and second comparison means (124A, ..., 124N) for comparing, with a predetermined interval of angular values (]-alret; a 2 ref[),the value of 25 the angle between each image vector (Phi2(j)) and a reference axis (X).

2. The measuring system (20) according to claim 1, wherein the first identifying device (101) comprises first determining means (104) for determining the Fresnel vector (Va, Vb, Vc) of each of the three measured voltages, first calculation means (105) for 30 calculating an image vector (Ph_61 (Vj)) via a first rotation of the Fresnel vector (Vj) of one among the two other measured voltages and first comparison means (106) for comparing an image vector (Ph_01(Vj)) with the Fresnel vector (V1) of the first measured voltage. 33

3. The measuring system (20) according to claim 2, wherein an index kp is associated to each phase to be identified, the index kp being an integer equal to 1 for the first phase and taking successively the integer values equal to 2 and 3 for the other phases, and wherein the value of the angle (61) of the first rotation depends on the index kp of 5 the phase to be identified, the value of the angle (61) of the first rotation being preferably equal to (kp-1) x 120*.

4. The measuring system (20) according to any one of the preceding claims, wherein an index kp is associated to each phase to be identified, the index kp being an integer 10 equal to 1 for the first phase and taking successively the integer values equal to 2 and 3 for the other phases, and wherein the value of the angle (62) of the second rotation depends on the index kP of the measured intensity.

5. The measuring system (20) according to claim 4 taken with claim 2, wherein the 15 value of the angle (62) of the second rotation is equal to ((kp-1) x 120*) - R, where R represents the value of the angle between the Fresnel vector (V1) of the first measured voltage and the reference axis (X).

6. The measuring system (20) according to any one of the preceding claims taken with 20 claim 2, wherein the second identifying device (125A, ..., 125N) comprises second determining means (121A, ... , 121N) for determining the Fresnel vector (Ix, ly, Iz) of each of the three measured intensities, and third comparison means for comparing, for each measured intensity (Ix, ly, lz), coordinates of the Fresnel vector (Ix, ly, lz) of said measured intensity with the coordinates of the Fresnel vector of a respective phase 25 voltage (V1, V2, V3).

7. The measuring system (20) according to any one of the preceding claims, wherein the measuring system (20) further comprises an indication device (109) for indicating the end of identification and able to emit a first signal, such as a first lighted signal, 30 when the first identifying device (101) identified the phase corresponding to each of the measured voltages (Va, Vb, Vc).

8. The measuring system (20) according to any one of the preceding claims, wherein the measuring system (20) is provided for a power installation (16) comprising primary 35 electrical conductors (34, 36, 38) and secondary electrical conductors (42A, 42B, .. 34 42N, 44A, 44B, ... , 44N, 46A, 46B, ..., 46N) able to enable the flowing of the alternating current, each secondary electrical conductor (42A, ..., 46N) being electrically connected to a corresponding primary electrical conductor (34, 36, 38), with the primary conductor (34, 36, 38) and the corresponding secondary conductor (42A, 5 ... , 46N) having substantially the same alternating voltage (V1, V2, V3), wherein the measuring system (20) comprises: - a primary module (60) comprising the voltage measuring element (66), the voltage measuring element (66) being able to measure the voltage of each primary conductor (34, 36, 38), 10 - at least one secondary module (62A, ..., 62N) comprising the three current sensors (76A, ... , 76N), each current sensor being able to measure the intensity of the current flowing in the corresponding secondary conductor (42A, ... , 46N), with the or each secondary module (62A, ... , 62N) being connected to the primary module (60) by a corresponding data link, 15 the primary module (60) further comprising emission means (107) for emitting, to the radio receiver (80A, ... , 80N) of the or of each secondary module (62A, 62B, ..., 62N), a first message (Ml) containing the values of measured voltages (Va, Vb, Vc), the or each secondary module (62A, ... , 62N) comprising reception means for receiving the first message (Ml), and 20 the measuring system (20) comprising synchronisation means (120A, ..., 120N) for time synchronisation of the measured intensities (lx, ly, lz) in relation to the measured voltages (Va, Vb, Vc).

9. Transforming station (10) for transforming an electric current having a first three 25 phase alternating voltage into an electric current having a second three-phase alternating voltage, the transforming station (10) comprising: - a first board (14) comprising input electrical conductors (24A, 26A, 28A, 24B, 26B, 28B) able to be connected to an electrical network (12), each input conductor (24A, 28B) being associated to a respective phase of the first alternating voltage, 30 - a second board (16) comprising primary output electrical conductors (34, 36, 38) and secondary output electrical conductors (42A, 44A, 46A, 42B, 44B, 46B, ... , 42N, 44N, 46N), each secondary output conductor (42A, ..., 46N) being connected electrically to a corresponding primary output conductor (34; 36; 38), with each output conductor (34, 42A, ..., 46N) being associated to a respective phase of the second alternating voltage, 35 - an electric transformer (18) connected between the first board (14) and the second board (16) and able to transform the first alternating voltage into the second alternating voltage, and - a system (20) for measuring at least one electrical quantity relative to the second 5 board (16), characterised in that the measuring system (20) is compliant with any one of the preceding claims.

10. Method for measuring at least one electrical quantity (Va, Vb, Vc) relative to a 10 power installation (16), the installation (16) comprising electrical conductors (34, 36, 38) able to enable the flowing of a three-phase alternating current, the method comprising the following steps: - measuring (150), by a voltage measuring element (66), the voltage of each of the electrical conductors (34, 36, 38), each electrical conductor (34, 36, 38) being 15 associated to a respective phase of the alternating network, - receiving (150), by an information processing unit (68), the values of the measured voltages (Va, Vb, Vc), the method being characterised in that it further comprises the following steps: - associating (155), by the information processing unit (68), in a predetermined manner 20 the first measured voltage (Va) with a first phase among the three phases, - identifying (165, 180), by a first identifying device (101), the phase corresponding to each of the two other measured voltages (Vb, Vc), - measuring (200; 300), by three current sensors (76A, ..., 76N), the intensity of the current flowing in each of the electrical conductors (42A, ... , 46N), and 25 - identifying (230, 250, 270; 330, 350, 370), by a second identifying device (125A, 125N)), the phase corresponding to each of the three measured intensities (Ix, ly, lz), wherein the step of identifying (230, 250, 270; 330, 350, 370) the phase corresponding to each of the three measured intensities comprises determining the Fresnel vector (Ix, ly, lz) of each of the three measured intensities, calculating three image vectors 30 (Ph_62(lj)) via a second rotation of the Fresnel vectors (Ix, ly, lz) of the three measured intensities and comparing, with a predetermined interval of angular values (]-a'ef; a 2 re4[),the value of the angle between each image vector (Ph_ 2(lj)) and a reference axis (X).

11. Method according to claim 10, wherein an index k, is associated to each phase to 35 be identified, the index k, being an integer equal to 1 for the first phase and taking 36 successively the integer values equal to 2 and 3 for the other phases, and wherein the value of the angle (62) of the second rotation depends on the index kp of the measured intensity, the value of the angle (02) of the second rotation being more preferably equal to ((k,-1) 5 x 120") - R, where R represents the value of the angle between the Fresnel vector (V1) of the first measured voltage and the reference axis (X).