Device for measuring active power in electric circuits

Abstract

The invention relates to a device DISP for measuring active power in electric circuits, the device DISP comprising current sensors CA configured to be opened and closed around an electric wire, at least one voltage sensor T and a concentrator CO, said current sensors CA, said voltage sensor T and said concentrator CO being connected by serial cables LS in a free order along a communication pipeline configured to cause sampled signals to transit.

Description

device for measuring active power in electrical circuits. Technical field of the invention

[0001] The present invention relates to a device for measuring active power in electrical circuits. More particularly, the invention finds an interesting application in monitoring consumption at the level of electrical sub-circuits in buildings. Technological background of the invention

[0002] Today, there are many devices for measuring active electrical power in a single-phase electrical circuit based on current and voltage measurements. There are also many devices for performing this measurement in the case of a three-phase circuit, based on current and voltage measurements.

[0003] These devices can be used in particular to establish a diagnosis and precise monitoring of the electrical consumption of the main equipment in a building by separately measuring the electrical circuits corresponding to this equipment, thus making it possible to detect avenues for savings and to monitor the effect of energy control actions.

[0004] To measure multiple electrical circuits, typically at the distribution board level, many devices rely on a star configuration in which each current and voltage sensor is connected directly to a concentration point, which we will call a hub, in which the calculations are carried out.

[0005] A disadvantage of such devices is that the number of connectors on the hub side is high, which generates significant manufacturing costs. In addition, the many long cables connecting the current and voltage sensors to the hub are difficult to position when installed in an electrical panel.

[0006] To measure multiple circuits, other devices consist of several concentration points connected together, each concentrator only calculating one power.

[0007] A disadvantage of such devices is the space requirement due to the use of numerous concentration points, while distribution boards often offer little free space. In addition, the multiplication of concentration points generates significant material costs.

[0008] Many devices use current loops that must be positioned by hand by placing the fingers near the conductor to be measured or adjacent conductors.

[0009] Furthermore, in many devices, these current loops have a significant thickness which does not allow easy positioning when the conductor does not have a sufficiently long straight section, in particular when it is curved towards the rear of the electrical panel at the circuit breaker outlet.

[0010] Additionally, in many devices, these current loops have a hinged portion that must completely surround the conductor before it can be closed.

[0011] A disadvantage of such devices is therefore the difficulty of installing current loops and the reluctance of users to bring their fingers close to the conductors.

[0012] Additionally, many devices lack simple means of measuring the voltage(s) present on the panel, necessary for calculating active power.

[0013] A disadvantage of such devices is the need to disconnect all or part of the elements in the panel or to add specific modules in the panel to measure the voltage(s).

[0014] In this context, the invention aims to provide an active power measuring device which avoids multiplying the number of concentrators or connectors at each concentrator, in order to significantly reduce the installation time and therefore the total cost of the solution.

[0015] One aspect of the invention relates to a device for measuring active power in electrical circuits, said device being remarkable in that it comprises current sensors configured to be opened and closed around an electric wire, at least one voltage sensor and a concentrator, said current sensors, said voltage sensor and said concentrator being connected by serial cables in a free order along a communication chain configured to transmit sampled signals.

[0016] For the remainder of the description, a sampled signal is understood to mean a sampled voltage measurement or current measurement signal having several voltage measurement values ​​or several current measurement values.

[0017] In addition to the characteristics which have just been mentioned in the preceding paragraph, the device according to this aspect of the invention may have one or more additional characteristics among the following, considered individually or according to all technically possible combinations.

[0018] According to a non-limiting aspect of the invention, each current sensor comprises three elements, two of the three elements each comprising a measurement half-winding and the other of the three elements comprising processing electronics, each of the two elements comprising a measurement half-winding being configured to be electrically connected to said element comprising processing electronics and at least one of said two elements comprising a measurement half-winding is configured to be spaced from the other of said two elements.

[0019] In a non-limiting embodiment, only one of the two elements comprising a measuring half-winding can be slid so as to be separated from the other element comprising a measuring half-winding. In another embodiment, the two elements comprising a measuring half-winding are slidable and can be separated from each other.

[0020] According to a non-limiting aspect of the invention, the element comprising processing electronics comprises at least one spring connector configured to establish electrical contact with at least one of said two elements comprising a measuring half-winding configured to be separated.

[0021] According to a non-limiting aspect of the invention, each element comprising a measuring half-winding is formed by a PCB printed circuit board carrying a Rogowski half-winding.

[0022] According to a non-limiting aspect of the invention, each voltage sensor is configured to measure a voltage of a phase and transmit a sampled voltage measurement signal along the communication chain.

[0023] According to a non-limiting aspect of the invention, each current sensor is configured to measure a current of a phase, receive the sampled voltage measurement signal of this same phase and perform an active power calculation from phase current measurement values ​​and this sampled voltage measurement signal.

[0024] According to a non-limiting aspect of the invention, each current sensor is configured to transmit calculated active powers to the concentrator, said concentrator being configured to transmit these calculated active powers remotely.

[0025] According to a non-limiting aspect of the invention, each current sensor is configured to measure a current of a phase and transmit a sampled current measurement signal of this phase along the communication chain, said concentrator being configured to receive the sampled voltage measurement signals, receive the sampled current measurement signals, perform active power calculations of each phase from these sampled voltage and current measurement signals and transmit these calculated active powers remotely.

[0026] According to a non-limiting aspect of the invention, each voltage sensor consists of a measuring part and an interchangeable adapter part clippable together, said interchangeable adapter part being configured to ensure electrical contact with at least two screws of a circuit breaker. Thus, the interchangeable adapter part can be replaced to adapt to different circuit breakers, the spacing and depth of the screws of which may be different.

[0027] According to a non-limiting aspect of the invention, when the voltage sensor is intended for measuring a single-phase voltage, the interchangeable adapter part comprises two electrical contact points for two adjacent screws of a single-phase circuit breaker.

[0028] According to a non-limiting aspect of the invention, when the voltage sensor is intended for measuring three-phase voltages, the interchangeable adapter part comprises four electrical contact points, one point for the neutral and one point for each of the three phases, for the four adjacent screws of a three-phase differential circuit breaker.

[0029] According to a non-limiting embodiment, the interchangeable adapter part configured to ensure electrical contact with at least two screws of a circuit breaker comprises magnets which can be brought into contact with screws of the circuit breakers. The measuring part can thus measure the potential difference between these screws in order to obtain a voltage measurement of the electrical network without tripping and without adding a module in the electrical panel.

[0030] According to a non-limiting aspect of the invention, the interchangeable adapter part comprises at least two contact pistons, for example compressible, each contact piston being configured to be introduced into a receptacle of a screw of said circuit breaker and to ensure electrical contact with said screw.

[0031] According to a non-limiting embodiment, a magnet is attached to each end of a contact piston. In this way, the interchangeable adapter part is attached to the screws of the electrical panel using the magnets and can be brought closer, when the contact pistons are compressible, to the circuit breaker by compressing the pistons to limit any excess thickness likely to hinder the closing of the faceplate of the electrical panel.

[0032] According to a non-limiting aspect of the invention, the interchangeable adapter part has a recess allowing the measuring part to be positioned set back from the front face of the circuit breaker.

[0033] According to a non-limiting aspect of the invention, the current sensors comprise opening and closing means configured to cooperate with a positioning clamp.

[0034] According to a non-limiting aspect of the invention, these opening and closing means are formed by two hoops, each hoop being configured to receive a branch of a positioning clamp, each element comprising a measuring half-winding comprising one of said hoops.

[0035] A different aspect of the invention relates to a positioning clamp comprising two branches articulated around an axis, each branch being configured to be temporarily inserted into one of the hoops of the current sensor that a device according to the invention comprises.

[0036] According to a non-limiting aspect of the invention, the branches of the positioning clamp comprise at their end a lateral stop projection configured to block said branches in said hoops of the current sensor when said branches are separated.

[0037] According to one embodiment, the invention relates to an active power measuring device in which:Current sensors, voltage sensors and a concentrator are connected in series, thus forming a communication chain;Each voltage sensor measures the voltage and transmits information relating to this voltage measurement along the chain;Each current sensor receives the information relating to the voltage measurement which concerns it and carries out its own active power calculation;Each current sensor transmits the calculated power values ​​to the concentrator along the chain.

[0038] The invention aims to provide an easy means of positioning current sensors.

[0039] The invention relates to a device whose current sensors can be opened from the front and can be operated by removable clamps.

[0040] The measuring device according to the invention makes it possible to solve the problems mentioned above.

[0041] According to a non-limiting embodiment, the device comprises current and voltage sensors which each comprise a processing unit and connectors enabling them to be connected in series. The concentrator also comprises a processing unit and a connector enabling it to be connected to the end of the chain. Thus, the device comprises cables which are on average much shorter and less bulky, since they are used to connect the sensors in close proximity and not each sensor to a concentrator. In addition, the concentrator may comprise only a single connector.

[0042] Furthermore, opening the sensors from the front and using removable clamps allows the sensor to be opened, positioned around the conductor and closed without difficulty or apprehension since the fingers remain at a distance from the conductors to be measured.

[0043] According to a non-limiting embodiment, each sensor is capable of measuring, performing calculations and managing the communication of information on the chain.

[0044] The measuring device according to the invention may also have one or more of the characteristics below, considered individually or in all technically possible combinations.

[0045] According to a non-limiting embodiment, the current sensors are small opening loops, which can be easily positioned around the conductor to be measured.

[0046] According to a non-limiting embodiment, the current sensors consist of two removable parts each comprising a half-loop for measuring the electromagnetic field, these two parts being able to be moved apart to pass the conductor to be measured and being brought together, thus establishing an electrical contact allowing the two half-loops to be connected.

[0047] According to a non-limiting embodiment, a half-loop is a half-measuring winding.

[0048] According to a non-limiting embodiment, the current sensors consist of three elements, two of them each comprising a measuring half-winding and the third comprising the processing electronics, each of the two half-winding elements being connectable to the processing element and at least one of the half-winding elements being able to be moved apart so as to pass the conductor to be measured.

[0049] According to a non-limiting embodiment, each half-coil element is a Rogowski PCB, defined as a PCB board carrying a half-Rogowski coil formed of tracks on both sides of the PCB and vias connecting them.

[0050] According to a non-limiting embodiment, the current sensors consist of three PCB boards, two of which are Rogowski PCBs and the third being a processing PCB defined as a PCB comprising the processing electronics.

[0051] According to a non-limiting embodiment, each of the two Rogowski PCBs is connectable to the processing PCB and at least one of the Rogowski PCBs is removable and can be moved apart so as to surround the conductor to be measured, and the processing PCB comprises a spring connector making it possible to establish contact with a track located on the removable Rogowski PCB when the latter is brought closer.

[0052] One of the advantages of this embodiment is that the two Rogowski PCBs can be made without any electronic components.

[0053] According to a non-limiting embodiment, the current sensors can be opened and closed using a clamp, said clamp comprising two articulated branches making it possible to separate and bring together the mechanical parts containing the half-winding elements.

[0054] According to a non-limiting embodiment, each half-winding element is integral with a, for example integrated in a, plastic support comprising a rectangular hoop, so that the branches of the clamp can be temporarily inserted into these hoops and be actuated to separate or bring the two half-windings together.

[0055] According to a non-limiting embodiment, the branches of the clamp comprise at their end a lateral stop projection capable of blocking said branches in the hoops of the current sensor when said branches are separated, so as to be able to pull the assembly into the open position and thus remove the sensor from its initial position around a conductor. Brief description of the figures

[0056] The figures are presented for information purposes only and in no way limit the invention.

[0057] illustrates a schematic representation of the device's current sensor in the closed position.

[0058] is a schematic representation of the device's current sensor in the open position.

[0059] is a schematic representation of another embodiment of the current sensor in the open position.

[0060] is a schematic representation of a chain of several sensors positioned near a series of circuit breakers.

[0061] is a schematic representation of the three PCBs, two of them each having a half-coil and the third having the processing electronics.

[0062] is also a schematic representation of the three PCBs, from a different viewing angle.

[0063] is a schematic representation of the clamp used to position the sensor.

[0064] is a schematic representation of the clamp being pressed into the rectangular hoops of the sensor and holding the sensor in the open position.

[0065] is a schematic representation of the voltage sensor for single-phase circuit breaker.

[0066] is a schematic representation of the voltage sensor for three-phase circuit breaker.

[0067] is a schematic representation of the voltage sensor positioned on a circuit breaker. Detailed description

[0068] According to a non-limiting embodiment illustrated 4, the invention relates to a DISP device for measuring active power in electrical circuits. The DISP device comprises:AC current sensors;A voltage sensor T; andA CO concentrator.

[0069] According to one embodiment, an AC current sensor shown in Figures 1 and 2 consists of two assemblies ENS1, ENS2 which can be moved apart and brought together so as to surround a conductor to be measured. The assembly ENS1 can slide along ENS2, the moving apart and bringing together can thus be carried out while the two assemblies remain integral.

[0070] As illustrated in Figures 5 and 6, the assembly ENS1 may comprise an element PCB1 comprising a measuring half-winding formed by a printed circuit board. The assembly ENS2 may comprise an element PCB2 comprising a measuring half-winding formed by a printed circuit board and an element PCB3 comprising processing electronics.

[0071] The circular notches EC1 and EC2 constitute a circular orifice surrounding the conductor to be measured when the assemblies ENS1 and ENS2 are brought together.

[0072] According to an alternative embodiment, the AC current sensor shown in the is made up of two elements PCB1, PCB2 each comprising a measuring half-winding and an element PCB3 comprising processing electronics. The two elements PCB1, PCB2 can both slide along the element PCB3 and thus be moved apart and closer together to surround the conductor to be measured.

[0073] When the ENS1 and ENS2 assemblies or both PCB1, PCB2 are separated, the AC current sensor can be slid around the conductor to be measured and then closed once the circular notches EC1 and EC2 are at the level of the conductor to be measured.

[0074] The ENS1 assembly includes an ERG lug and the ENS2 assembly includes an OR port. When the ENS1 and ENS2 assemblies are brought together as closely as possible, the ERG lug clips into the OR port, thus keeping the device closed.

[0075] According to one embodiment, the voltage sensor T shown in the is intended to measure a single-phase voltage and is made up of a measuring part MES and an interchangeable adapter part ADPT, the two parts can be clipped using a clip system CL and an orifice OR2. The measuring part MES comprises an electronic card intended to measure the voltage and the interchangeable adapter part ADPT comprises contact pistons PIST1 and PIST2 which can be pushed into the cavities at the bottom of which are the circuit breaker screws. The contact pistons PIST1 and PIST2 are compressible, so as to be able to adapt to various distances from the screws. Magnets are fixed to the end of the contact pistons PIST1 and PIST2, allowing the interchangeable adapter part ADPT to be held by magnetic adhesion to the screws.In this way, the interchangeable adapter part ADPT is fixed using magnets and can be brought closer to the circuit breaker by compressing the contact pistons PIST1 and PIST2 to limit any excess thickness that could hinder the closing of the electrical panel faceplate.

[0076] The represents the voltage sensor T positioned on a D1 circuit breaker. The interchangeable adapter part ADPT has a recess that allows the measuring part MES to be positioned set back from the front of the D1 circuit breaker so that the voltage sensor T as a whole does not protrude too much and the front panel of the electrical panel can be closed correctly.

[0077] According to a non-limiting embodiment, the voltage sensor T2 shown in is intended to measure three three-phase voltages and is made up of a measuring part MES2 and an interchangeable adapter part ADPT2, the measuring part MES2 and the interchangeable adapter part ADPT2 being able to be clipped using a clip system CL2 and an orifice OR2. The measuring part MES2 comprises an electronic card intended to measure the three voltages and the interchangeable adapter part ADPT2 comprises contact pistons PIST3, PIST4, PIST5 and PIST6.

[0078] La represents the DISP device positioned on a series of five D circuit breakers.

[0079] The AC current sensors are positioned around the conductors to be measured (CM), which exit the circuit breakers. The voltage sensor (T) is positioned at the screws of one of the circuit breakers. The CO concentrator is positioned next to the series of circuit breakers.

[0080] The AC current sensors, the T voltage sensor and the CO concentrator are connected by the LS serial cables, thus forming a communication chain.

[0081] In one embodiment, the sensor T measures voltage at high frequency, for example at a frequency of 4000 Hz, and transmits the measured values ​​along the chain. The AC current sensors measure current at high frequency, for example at a frequency of 40000 Hz, and use the voltage values ​​transmitted by the voltage sensor T to combine them with the current measurements they measure to obtain active power.

[0082] When the installation is supplied with three-phase power, three voltage measurements made by three voltage sensors are used, one for each of the three phases. Each AC current sensor is then configured to use the sampled voltage measurement signals corresponding to the correct phase. Each voltage sensor T transmits its values ​​and each AC current sensor identifies the origin of the voltage values ​​being transmitted and uses those assigned to it.

[0083] In one embodiment, the voltage measurement signals are first communicated to the CO concentrator, which then retransmits them to the AC current sensors.

[0084] The AC current sensors transmit the active powers they have calculated along the communication chain to the CO concentrator.

[0085] In another embodiment, the voltage measurement signals and the current measurement signals are transmitted to the CO concentrator which calculates the active powers.

[0086] The CO concentrator receives the voltage and current measurement signals or the powers, processes them, for example to aggregate them temporally, stores the results obtained and transmits them at regular intervals, typically via a connection to a data network, such as an NB-IoT or LoRaWAN wireless network.

[0087] In one embodiment, the LS series cables include a dedicated synchronization wire allowing the CO hub to send all T voltage and AC current sensors a synchronous signal allowing them to synchronize their measurements.

[0088] In one embodiment shown in Figures 5 and 6, the AC current sensor comprises three printed circuit boards, including a first half-coil printed circuit board PCB1, a second half-coil printed circuit board PCB2 and a process printed circuit board PCB3. The printed circuit boards PCB1 and PCB2 each carry a half Rogowski coil formed by traces on both sides of the printed circuit board and vias connecting them.

[0089] The three circuit boards are shown in Figures 5 and 6.

[0090] The third printed circuit board PCB3 includes two connectors CS1 and CS2 intended to be connected to the LS serial link cables.

[0091] The third printed circuit board PCB3 comprises two spring connectors CR1, CR2 intended to provide electrical contact with tracks or contact pads on the first and second printed circuit boards PCB1 and PCB2. Thus, when the AC current sensor is closed, that is to say when the first and second printed circuit boards PCB1 and PCB2 are brought together, the connector CR1 comes into contact with the contact pads of the first printed circuit board PCB1, so as to be able to measure the signal from the Rogowski half-coils carried by the first printed circuit board PCB1, in addition to the signal from the Rogowski half-coil carried by the second printed circuit board PCB2.

[0092] This represents a specific P positioning clamp intended to facilitate the installation of AC current sensors.

[0093] The positioning clamp P comprises two branches BR1 and BR2 articulated around an axis AX.

[0094] The positioning clamp P can be manipulated so as to introduce the branches BR1 and BR2 into the rectangular hoops AR1 and AR2 of the AC current sensor.

[0095] The positioning clamp P then allows the AC current sensor to be opened or closed by moving the ENS1 and ENS2 assemblies or PCB1, PCB2 elements apart or closer together.

[0096] The BR1 branch includes a BU1 stop projection. The BR2 branch includes a BU2 stop projection.

[0097] Shows the branches BR1 and BR2 of the positioning clamp P, inserted into the rectangular hoops AR1, AR2 of the AC current sensor. The positioning clamp P is in the open position, branches apart, which induces an open position of the AC current sensor.

[0098] The stop projections BU1, BU2 allow the AC current sensor to be removed from its position around the conductor. In the open position, the stop projections BU1, BU2 protrude beyond the lateral sides of the rectangular hoops AR1, AR2 and thus provide a lock for pulling the AC current sensor using the positioning clamp P, even in the event of resistance from various friction or obstacles.

Claims

Device (DISP) for measuring active power in electrical circuits, said device (DISP) being characterized in that it comprises current sensors (CA) configured to be opened and closed around an electric wire, at least one voltage sensor (T) and a concentrator (CO), said current sensors (CA), said voltage sensor (T) and said concentrator (CO) being connected by serial cables (LS) in a free order along a communication chain configured to transmit sampled signals. Device (DISP) according to the preceding claim, characterized in that each current sensor (CA) comprises three elements (PCB1, PCB2, PCB3), two of the three elements (PCB1, PCB2) each comprising a measuring half-winding and the other of the three elements (PCB3) comprising processing electronics, each of the two elements (PCB1, PCB2) comprising a measuring half-winding being configured to be electrically connected to said element (PCB3) comprising processing electronics and at least one of said two elements (PCB1, PCB2) comprising a measuring half-winding is configured to be spaced from the other of said two elements (PCB1, PCB2). Device (DISP) according to the preceding claim, characterized in that the element (PCB3) comprising processing electronics comprises at least one spring connector configured to establish electrical contact with at least one of said two elements (PCB1, PCB2) comprising a measuring half-winding configured to be separated. Device (DISP) according to claim 2 or 3, characterized in that each element (PCB1, PCB2) comprising a measuring half-winding is formed by a printed circuit board carrying a Rogowski half-winding. Device (DISP) according to any one of the preceding claims, characterized in that each voltage sensor (T) is configured to measure a voltage of a phase and transmit a sampled voltage measurement signal along the communication chain. Device (DISP) according to the preceding claim, characterized in that each current sensor (CA) is configured to measure a current of a phase, receive the sampled voltage measurement signal of this same phase and perform an active power calculation. Measuring device (DISP) according to claim 6, characterized in that each current sensor (CA) is configured to transmit calculated active powers to the concentrator (CO), said concentrator (CO) being configured to transmit these calculated active powers remotely. Device (DISP) according to claim 5, characterized in that each current sensor (CA) is configured to measure a current of a phase and transmit a sampled current measurement signal of this phase along the communication chain, said concentrator (CO) being configured to receive the sampled voltage measurement signals, receive the sampled current measurement signals, perform active power calculations of each phase and transmit these calculated active powers remotely. Device (DISP) according to any one of the preceding claims, characterized in that each voltage sensor (T) consists of a measuring part (MES) and an interchangeable adapter part (ADPT) clippable together, said interchangeable adapter part (ADPT) being configured to ensure electrical contact with at least two screws of a circuit breaker (D, D1). Device (DISP) according to the preceding claim, characterized in that the interchangeable adapter part (ADPT) comprises at least two contact pistons (PIST1, PIST2), each contact piston (PIST1, PIST2) being configured to be introduced into a receptacle of a screw of the circuit breaker (D, D1) and to ensure electrical contact with said screw. Device (DISP) according to any one of claims 9 or 10, characterized in that the interchangeable adapter part (ADPT) has a release allowing the measuring part (MES) to be positioned set back from a front face of the circuit breaker (D, D1). Device (DISP) according to any one of the preceding claims, characterized in that the current sensors (CA) comprise opening and closing means configured to cooperate with a positioning clamp (P). Device (DISP) according to the preceding claim, characterized in that these opening and closing means are formed by two hoops (AR1, AR2), each hoop (AR1, AR2) being configured to receive a branch (BR1, BR2) of a positioning clamp (P), each element (PCB1, PCB2) comprising a measuring half-winding comprising one of said hoops (AR1, AR2). Positioning clamp (P) comprising two branches (BR1, BR2) articulated around an axis (AX), each branch (BR1, BR2) being configured to be temporarily inserted into one of the hoops (AR1, AR2) of the current sensor (CA) which comprises a device (DISP) according to the preceding claim. Positioning clamp (P) according to the preceding claim, characterized in that the branches (BR1, BR2) of the positioning clamp (P) comprise at their end a lateral stop projection (BU1, BU2) configured to block said branches (BR1, BR2) in said hoops (AR1, AR2) of the current sensor (CA) when said branches (BR1, BR2) are separated.

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