Arc detection antenna

Abstract

An electric meter for detecting an electric arc discharge between an electric meter and a meter socket in a utility box connected to a power line, the electric meter comprising: a base plate assembly comprising a conductor connecting two meter blades, each of which is positioned in a corresponding socket jaw of a meter socket to electrically connect the electric meter to the meter socket; and a housing assembly configured to be coupled to the base plate assembly, the housing assembly comprising a multilayer circuit board comprising a first layer circuit board hosting a first arc detection antenna for emitting a signal indicating an electric arc discharge, and a second layer circuit board hosting a second arc detection antenna for receiving the signal, wherein the first and second layers are electrically insulated from each other.

Description

Technical Field

[0001] Field of the Invention The present disclosure generally relates to the field of safety in an electric utility system, and more specifically, to an arc detection antenna installed in an electric meter to detect an electric arc between electric measurement components included in a utility box at a facility.

Background Art

[0002] Background All residential and commercial facilities include an electric meter to enable a power company to monitor the power consumption within the facility. To do this, the electric meter is electrically connected to a meter socket, which is typically located within a utility box disposed on an outer wall of the facility. The electric meter may include a meter blade that is received in the meter socket and held in place by the tension applied to the blade by the meter socket.

[0003] In some cases, when installing a new meter to replace an old meter, if it is not installed correctly, a phenomenon known as "arc discharge" may occur, where an electric arc is formed in the gap between the meter blade and the corresponding socket jaw of the meter socket when the meter is installed. Arc discharges may also occur randomly after the installation period. For example, reducing the tension of the socket increases the contact resistance, which then increases the heat at the contact, leading to corrosion and progression into the gap that leads to arc discharge. The gap provides an environment that promotes arc discharge. The presence of arc discharge in an electrical system can cause high heat and, in some cases, fire, which can cause significant damage to the components of the electrical system and the facility, and can also injure people such as workers assisting with meter replacement. Therefore, it is important to detect the arc discharge condition before damage or danger occurs.

[0004] In other cases, arc discharges may occur elsewhere on the electrical network near the meter, for example, within a facility and / or near high-voltage lines supplying the facility. As with the arc discharges described above, it is important to detect these arc discharge conditions so that the relevant authorities can take action before further damage or danger occurs.

[0005] An electric meter can be configured with an arc detection component to detect arc discharge. However, because high voltage conditions occur near the location of the arc discharge, the arc detection component is usually placed within the meter, away from the meter blade and meter socket, and away from the high-voltage lines entering the meter. If the distance between the arc detection component and the location of the arc discharge is large, the detection of the arc discharge may become inaccurate.

[0006] International Publication No. 2021 / 154728 proposes an electric meter in a utility box capable of detecting arc discharge conditions within a meter socket in a facility or at any location along a power line, provided that the RF noise generated by the arc discharge is strong enough to be detected. The arc detection component is placed in a sealed space close to the AC power connection to the meter. [Overview of the project] [Means for solving the problem]

[0007] overview Generally, the present disclosure improves the accuracy of arc detection by providing a multilayer circuit board having (i) a first layer hosting a first arc detection antenna connected to the high-voltage lines of an electric meter, and (ii) a second layer electrically isolated from the first layer and hosting a second arc detection antenna connected to an arc detection circuit.

[0008] Typically, arc discharge conditions introduce disturbances that manifest as high-frequency (RF) noise on high-voltage lines. However, known electric meters usually attempt to minimize the risk of circuit damage due to proximity to high-voltage conditions by positioning the circuit containing the arc detection function as spatially as possible away from the high-voltage lines and / or behind the high-voltage protection system and circuit. As a result, disturbances on high-voltage lines caused by arc discharge conditions are attenuated when picked up by the arc detection circuit. In such configurations, the ability to accurately detect arc discharges is reduced accordingly.

[0009] In contrast, in this disclosure, the high-voltage line is routed directly to the meter's circuitry, specifically to the first layer of a multilayer circuit board and the antenna hosted thereon. Thus, the antenna is electrically connected directly to the high-voltage line and therefore transmits a signal corresponding to any signal present on the high-voltage line.

[0010] The second layer of the multilayer circuit board has a corresponding antenna on it, which is connected to an arc detection circuit and picks up the signal transmitted by the antenna on the first layer. The first and second layers are separated and electrically isolated from each other so that there is no direct connection from high-voltage lines to the layers containing the rest of the circuit of the multilayer circuit board.

[0011] If an arc discharge condition causes a disturbance in the high-voltage line, this disturbance appears in the signal transmitted by the first antenna and picked up by the second antenna, which can be detected by the arc detection circuit. Since the high-voltage line and the arc detection circuit are separated only by the space between the antennas, the disturbance signal is not substantially attenuated, and therefore the arc detection accuracy is significantly improved compared to configurations such as the one shown in International Publication No. 2021 / 154728.

[0012] Therefore, it will be understood that this disclosure generally relates to an arc detection circuit coupled to the AC line input of a meter, which provides high AC isolation to the detection circuit while not degrading the RF noise generated by the arc discharge so as to be detected by the circuit.

[0013] Accordingly, according to one aspect of the present disclosure, an electric meter for detecting an electric arc discharge is provided. The electric meter comprises a base plate assembly comprising a conductor for connecting meter blades, each of which is configured to be positioned in a corresponding socket jaw of a meter socket in a utility box connected to a power line to electrically connect the electric meter to the meter socket; and a housing assembly configured to be coupled to the base plate assembly, the housing assembly comprising a multilayer circuit board comprising a first layer for hosting a first arc detection antenna for emitting a signal indicating an electric arc discharge, and a second layer for hosting a second arc detection antenna for receiving the signal, wherein the first and second layers are electrically isolated from each other.

[0014] Advantageously, as mentioned above, by providing two separate layers, each equipped with an antenna, it becomes easier to detect arc detection signals with a stronger signal-to-noise ratio than is possible using known arc detection systems.

[0015] Optionally, the multilayer circuit board includes a third layer containing an insulating material between the first and second layers.

[0016] Advantageously, the third layer further isolates the first layer coupled to the high-voltage lines from the second layer hosting the circuit, increasing the dielectric breakdown voltage between the first and second layers and avoiding the risk of damage to the circuit on the second layer due to its extremely close proximity to the high voltage on the first layer. Optionally, the insulating material may include FR4 material. FR4 is a glass-reinforced epoxy laminate material that increases the dielectric breakdown voltage but does not disrupt or otherwise affect RF noise coupling between arc detection antennas.

[0017] Optionally, the electric meter includes a bypass line configured to bypass the first layer of a multilayer circuit board to electrically couple the power lines to a circuit through the meter socket.

[0018] Advantageously, by routing the lines from the high-voltage circuit, including the power lines, in close proximity to the arc detection circuit to bypass the high-voltage protection of other components of the meter, it is ensured that the signal indicating an arc discharge is not attenuated by other components of the meter, thereby ensuring that the signal-to-noise ratio is better than that of known arc detection systems.

[0019] Optionally, the first antenna is configured to emit a signal indicating an electric arc discharge when an electric arc discharge occurs in a circuit having a bypass wire.

[0020] Optionally, the first arc detection antenna is configured to emit a signal in response to a voltage pulse in a bypass line indicating an electric arc discharge.

[0021] Advantageously, when an arc discharge occurs, it typically creates a pulse in the circuit voltage. The bypass line advantageously sends this pulse to a first arc detection antenna, which emits, picks up, and analyzes the pulse to detect all arc discharges near the multilayer printed circuit board without the risk of interference or attenuation by other components of the meter.

[0022] Optionally, the bypass line is electrically coupled to the first antenna through a surge protection element.

[0023] Optionally, the surge protection element comprises a metal oxide varistor and / or a resistor.

[0024] Advantageously, surge protection facilitates the safe delivery of high voltages to multilayer printed circuit boards by having the varistor configured to increase resistance in response to sudden surges.

[0025] Optionally, the first layer and the second layer are spatially separated from each other.

[0026] Advantageously, there is a spatial and / or electrical separation between the high voltage on the first layer and the second layer that can host operating circuits such as microprocessors and other components, so that the operating circuits are protected from the risk of damage that can be caused by the proximity of the high voltage circuit.

[0027] Optionally, the electrical meter comprises a current transformer structure comprising a current transformer holder and a current transformer cover that form a sealed space, a current transformer configured to measure the current supplied to the electrical meter, disposed within the sealed space and inductively coupled to a conductor, and the first arc detection antenna and the second arc detection antenna are outside the current transformer structure and spaced apart from the current transformer structure.

[0028] Advantageously, the separation from the current transformer structure and the current transformer reduces noise and / or attenuation from these components, ensuring a strong signal-to-noise ratio for the arc detection signal.

[0029] Optionally, the first and / or second arc detection antenna comprises one or more bending elements.

[0030] Optionally, the bending of one or more bending elements is a 90-degree bend.

[0031] Optionally, the length of one or more bending elements is 6 - 7 cm.

[0032] Advantageously, by providing one or more bending elements on the antenna, the total length of the antenna elements can be provided in a smaller space, thereby reducing the space requirements of the antenna on the printed circuit board and thereby integrally miniaturizing the arc detection system.

[0033] Optionally, the meter blades are current blades, and the conductors are configured to connect the voltage from the meter blades to a multilayer circuit board, with the number of meter blades being 4 or 8.

[0034] According to a second aspect of the present disclosure, an arc detection circuit for an electric meter is provided, the electric meter comprising a base plate assembly having conductors for connecting meter blades, each of which is configured to be positioned in a corresponding socket jaw of a meter socket in a utility box connected to a power line to electrically connect the electric meter to the meter socket, and a housing assembly configured to be coupled to the base plate assembly, the arc detection circuit comprising a multilayer circuit board comprising a first layer hosting a first arc detection antenna for emitting a signal indicating an electric arc discharge, and a second layer hosting a second arc detection antenna for receiving the signal.

[0035] The advantages described in relation to the first aspect are equally applicable to the corresponding features in the second aspect.

[0036] A third aspect of the present disclosure provides a method for detecting an electric arc discharge between an electric meter and a meter socket in a utility box connected to a power line, wherein the electric meter comprises a base plate assembly comprising a conductor connecting two meter blades, each of which is positioned in a corresponding socket jaw of a meter socket to electrically connect the electric meter to the meter socket; and a housing assembly configured to be coupled to the base plate assembly, the housing assembly comprising a multilayer circuit board comprising a multilayer circuit board having a first layer hosting a first arc detection antenna and a second layer hosting a second arc detection antenna, wherein the method includes using the first arc detection antenna to emit a signal indicating an electric arc discharge, using the second arc detection antenna to receive a signal indicating an electric arc discharge, and using an arc detection circuit to detect an electric arc discharge.

[0037] The advantages described in relation to the first aspect are equally applicable to the corresponding features in the third aspect.

[0038] Brief explanation of the drawing These embodiments and other embodiments will be described below with reference to the following figures. [Brief explanation of the drawing]

[0039] [Figure 1A] This is a block diagram illustrating an example of an electric meter, utility box, and meter socket as disclosed herein. [Figure 1B] This is a block diagram illustrating an example of an electric meter, utility box, and meter socket as disclosed herein. [Figure 2] This is a block diagram illustrating a simplified example of components housed in an electric meter capable of detecting an arc discharge state present in a utility box, as disclosed herein. [Figure 3]This is a block diagram illustrating a simplified example of components housed in an electric meter capable of detecting an arc discharge state present in a utility box, as disclosed herein. [Figure 4] This disclosure shows a cross-sectional side view of an electric meter capable of detecting the arc discharge state present in a utility box. [Figure 5A] A portion of the circuit diagram provided in this disclosure is shown as an example. [Figure 5B] A portion of the circuit diagram provided in this disclosure is shown as an example. [Modes for carrying out the invention]

[0040] Detailed description of the drawing Figures 1A and 1B show block diagrams of an electric meter, a utility box, and a meter socket. Figure 1A depicts an electric meter 102 that includes one or more blades, such as four blades (two inputs and two outputs) or eight blades (four inputs and four outputs). Figure 1A also shows a utility box 100 that includes a meter socket 104. The meter socket 104 includes a receptacle 105, also called a "socket jaw" 105, into which the blades 103 can be positioned or engaged. The socket jaw 105 includes a utility-side socket jaw 105A and a facility-side socket jaw 105B. The electric meter 102 can be fitted into the meter socket 104 so that the blades 103 are positioned in the socket jaw 105, as shown by the dotted line in Figure 1A. By positioning the blades 103 within the socket jaw 105, the electric meter 102 is electrically connected to the meter socket 104. The meter socket 104 may include a spring or other means to apply tension to the blade and maintain its position within the socket jaws of the meter socket 104. The meter socket 104 and the blade may each include one or more surfaces made of a conductive material to allow electricity to flow between the meter socket 104 and the blade.

[0041] The blade 103 and socket jaw 105 may be configured to transmit electrical signals between the utility side of the meter socket 104 and the electric meter 102, and between the electric meter 102 and the facility side of the meter socket 104. For example, an electrical signal received from the utility may be transmitted to the electric meter 102 via the utility-side socket jaw 105A and the utility-side blade of the electric meter 102 (not visible in Figure 1A). In addition, electrical signals may be transmitted to the facility via the facility-side blade 103 and facility-side socket jaw 105B of the electric meter 102. The electric meter 102 may perform operations including generating a voltage detection signal or a current detection signal, determining a measurement, and other operations as the electrical signal is transmitted between the utility side and the facility side. In addition, the electric meter 102 may also be configured to detect arc discharge conditions near the blade 103 and socket jaw 105.

[0042] Figure 1B illustrates an example configuration of a utility box 100 in which an electric meter 102 is installed. The electric meter 102 may be installed by being placed in a meter socket 104 (not visible in Figure 1B). The utility box 100 may be located close to a facility 180 that receives power from a power company. A power line 190 may be electrically connected to the utility box 100 to supply power from the power company to the facility 180. Power from the power line 190 may be routed through a meter socket 104 included in the utility box 100, for example, by being transmitted between the power company-side meter socket jaw and the facility-side meter socket jaw via the installed electric meter 102. The installed electric meter 102 can measure various aspects of the power supplied via the power line 190, such as determining the overall power usage by the facility 180. As will be described later, the installed electric meter 102 may also detect arc discharge conditions between the electric meter 102 and the meter socket 104 in the utility box 100. The detected arc discharge state can be used to determine whether to disconnect the electric meter 102 from the meter socket 104, thereby disconnecting the electric meter 102 from the power line 190, or to instruct the electric meter 102 to open one or more disconnection switches within the electric meter 102.

[0043] Figure 2 is a block diagram illustrating a simplified example of components housed in an electric meter 102 capable of detecting an electric arc between the electric meter 102 and a meter socket 104, according to the present disclosure. The electric meter 102 shown in Figure 2 includes a meter base 220, a measuring circuit 250, and a communication component 208, which are supported by the housing of the electric meter 102 and are at least partially housed within the housing of the electric meter 102.

[0044] The meter base 220 includes two pairs of terminals 224A / 228A and 224B / 128B (such as the meter blade 103 shown in Figure 1), which are electrically connected by conductors 226A and 226B, respectively. Each of the terminals 224A, 224B, 228A, and 228B extends from the housing of the electric meter 102 and engages with a meter socket (e.g., the meter socket 104 shown in Figure 1) connected to a power line (e.g., the power line 192 shown in Figure 1). Each of the terminal pairs 224A / 228A and 124B / 128B is configured to connect in series with a conductor in the power line, so that all electrical signals passing through the power line from the energy source to the load pass through the terminal pairs 224A / 228A and 224B / 228B to the load. The terminal pairs 224A / 228A and 224B / 228B, as well as the conductors 226A and 226B, effectively become part of the power line connected between the source and the load when the electric meter 102 is connected to the meter socket.

[0045] The meter base 220 further includes current transformers 232A and 232B inductively coupled to conductors 226A and 226B, respectively. Current transformers 232A and 232B are electrically connected to the measurement circuit 210 of the measurement circuit 250. The AC waveforms in conductors 226A and 226B induce currents in current transformers 232A and 232B, respectively. This current can be used to monitor the current level in the power line, for example, by a current sensing circuit in the measurement circuit 210. The measurement circuit 210 may include other circuits for measurement purposes, such as a voltage sensing circuit for measuring the voltage of the power line. The voltage sensing circuit may be connected to terminals 224A, 228A, 124B, and 128B to measure voltage. The voltage sensing signals and current sensing signals generated by the voltage sensing circuit and current sensing circuit, respectively, may be routed to a processing device (not shown in Figure 2) in the measurement circuit 250, for example, to determine the power consumed by the facility. Although this specification describes two current transformers, 232A and 232B, it is assumed that any number may be provided depending on the meter type, such as whether it is a single-phase, two-phase, or three-phase service meter.

[0046] To detect the arc discharge state, the electric meter 102 includes bypass lines 238A and 238B directly coupled to a circuit having a power line and a corresponding pair of blades, which directly feed the high-voltage signal of the power line to the vicinity of the measuring circuit 250, specifically to the first arc detection antenna 234A. The first arc detection antenna 234A is not directly electrically connected to the arc detection circuit 262 of the measuring circuit 250, but is instead positioned adjacent to the second arc detection antenna 234B. The second arc detection antenna 234B is directly electrically connected to the arc detection circuit 262. The first arc detection antenna 234A emits a signal, which is picked up by the second arc detection antenna 234B and fed from the second arc detection antenna 234B to the arc detection circuit 262 to detect the arc discharge state between terminals 224A and 228A and the corresponding socket jaws in the meter socket. Although not shown in Figure 2, corresponding arrangements may be provided for terminals 224B and 228B and the corresponding socket jaws in the meter socket. For example, the arc detection circuit 262 can detect an arc discharge state by analyzing the signal received from the arc detection antenna, by filtering the received signal to focus on signals in a specific frequency band. Thus, the first and second arc detection antennas 234A, 234B are spatially isolated from the components of the meter base 220, including the current transformer 232A (or 232B) and any enclosed structure in which the current transformer is sealed (referred to herein as the current transformer structure 236A (or 236B)). Bypass lines 238A and 238B are provided with surge protection 244, 242 in the form of a metal oxide varistor (MOV) 244 and / or resistor 242 setup configured to increase resistance in response to sudden voltage surges that could enter the antenna and potentially pose a risk of dielectric breakdown from the first layer of the multilayer circuit board to the second layer hosting arc detection and / or other circuits.

[0047] The electric meter 102 may be communicatively connected to a remote device (not shown in Figure 2) through a communication component 208. In some embodiments, the communication component 208 may include one or more communication devices, such as a communication antenna and a radio, to send and receive message signals over a network between the electric meter 102 and the remote device. For example, the electric meter 102 may send a message to the remote device containing measured power consumption or other data. The remote device may be communicatively coupled to multiple meters and communicate messages over the network to a central system, such as a central system associated with a power company operator. In some embodiments, the communication component 108 may also send a message indicating the state of an arc discharge in the utility box 100. The central system may process the message and, in response, send a signal instructing the electric meter 102 to cut off power to the facility when an arc discharge occurs.

[0048] The electric meter 102 can cut off power to the facility by opening the disconnection switches 240A and / or 240B, as shown in Figure 2. Each of the disconnection switches 240A and 240B moves between a closed position and an open position. In the closed position, the disconnection switches 240A and 240B establish an electrical connection between terminal pairs 224A / 228A and 224B / 228B, respectively. In the open position, the disconnection switches 240A and 240B disconnect terminal pairs 224A / 228A and 224B / 228B, respectively. The disconnection switches 240A and 240B move between the closed and open positions based on a control signal from the measuring circuit 250. For example, the measuring circuit 250 may include a disconnection circuit 222 that includes an actuation device or other means to control the movement of the disconnection switches 240A and 240B between the closed and open positions.

[0049] Figure 3 is a block diagram depicting the arc detection circuit 262 and antennas 234A, 234B of Figure 2. It will be understood that Figure 3 is simplified and therefore does not show other components of the circuit, such as those described in the arc detection circuit of International Publication No. 2021 / 154728. However, it will be assumed by those skilled in the art that these other components exist. As shown in Figure 3, the arc detection circuit comprises a multilayer circuit board having at least two layers 318A, 318B spatially separated from each other by a distance 319. The first layer 318A hosts the first arc detection antenna 234A. The first layer 318 is electrically coupled through bypass lines 238A, 238B to a high-voltage circuit, i.e., a circuit that directly includes power lines, i.e., not behind MELF or other high-voltage protection systems or other components of the meter. It will be understood that the bypass lines 238A, 238B may include one or more conductors, such as insulated leads, cables or wires, that can safely withstand the typical voltages present on the power lines. The bypass lines 238A and 238B in Figure 3 are connected to the first layer 318A at one or more points. Surge protection 323, such as MOV and / or resistors and / or other components, is provided to ensure that any surges passing through the bypass lines 238A and 238B can be safely prevented.

[0050] As described above, the first layer 318A hosts the first arc detection antenna 234A, which is coupled to surge protection using the conductive trace 324. When an arc discharge occurs and a signal indicating the arc discharge is present in the circuit including the bypass lines 238A and 238B, for example, when a voltage pulse is present, the first arc detection antenna 234A emits an electromagnetic wave signal corresponding to the pulse application.

[0051] A second layer 318B, spatially and electrically isolated from the first layer 318A, hosts a second arc detection antenna 234B. The dotted lines in Figure 3 indicate that the corresponding components are hidden behind the first layer 318A in Figure 3. The second arc detection antenna 234B is coupled to one or more operating components 262A of an arc detection circuit 262, which includes other components necessary for amplifying and detecting the arc discharge signal, such as resistors, diodes, capacitors, microprocessors and / or those described in International Publication No. 2021 / 154728. These components are merely illustrative and not intended to be limiting. Those skilled in the art will understand other methods of implementing the arc detection circuit.

[0052] As described above, when an arc discharge occurs, a signal is emitted by the first arc detection antenna 234A. The signal is picked up by the second arc detection antenna 234B and sent to the operating component 262A of the arc detection circuit 262, enabling the detection of the arc discharge. Specifically, since the first layer 318A and the second layer 318B are spatially separated and electrically isolated from each other, when the first layer 318A, on which the first arc detection antenna 234A is hosted, is directly coupled to the high-voltage circuit of the power lines passing through the bypass lines 238A and 238B, there is spatial and electrical isolation between the high voltage on the first layer 318A and the rest of the measurement circuit 250 on the second layer 318B. Thus, the operating component 262A of the arc detection circuit 262, such as the microprocessor and other components, and the components of the measurement circuit 250 on the printed circuit board are protected from the risk of damage that may occur due to proximity to the high-voltage circuit. At the same time, any pulsed signal within a high-voltage circuit exhibiting arc discharge remains strong (i.e., with a lower signal-to-noise ratio compared to known systems) and is not attenuated.

[0053] Figure 4 shows a cross-sectional side view of an electric meter 300 capable of detecting an arc discharge state in a utility box according to the present disclosure. As shown in Figure 4, the electric meter 300 includes a base plate assembly 302 and a housing assembly 304. Various components of the meter base 220 discussed above with respect to Figure 2 are mounted on the base plate assembly 302. For example, in Figure 4, two meter blades 312 and 310 are connected by a conductor 314 that passes through a ring formed by a current transformer structure 306. The meter blades 312 and 310 extend from the outside of the base plate 320 of the base plate assembly 302 so that they can be positioned within the socket jaws of the meter socket when installed in a utility box.

[0054] In Figure 4, the housing assembly 304 of the electric meter 300 includes a register cover 308, at least two printed circuit boards 318, and other components. When the register cover 308 is connected to the base plate 320, it seals the printed circuit boards 318. In some examples, the printed circuit boards 318 are mounted at the front end of the housing assembly 304, i.e., the end away from the base plate 320. In some examples, the measuring circuit 210 and the arc detection circuit 262 discussed above with respect to Figure 2 are placed on one printed circuit board 318. In other examples, the measuring circuit 210 and the arc detection circuit 262 may be placed on separate printed circuit boards 318.

[0055] Although details of the printed circuit board 318 are not shown in Figure 4, it is assumed that the first arc detection antenna 234A in Figures 2 and 3 is hosted on the first layer 318A, and the second arc detection antenna 234B in Figure 2 is hosted on the second layer 318B. As described above, the operating components of the arc detection circuit 262, such as the microprocessor and other components, as well as the components of the measurement circuit 250 on the printed circuit board, remain protected from potential damage caused by proximity to the high-voltage circuit, while any pulse signals in the high-voltage circuit indicating an arc discharge remain strong (i.e., with a lower signal-to-noise ratio compared to known systems) and are not attenuated. Specifically, compared to a system such as the one provided in International Publication No. 2021 / 154728, the signal analyzed by the arc detection circuit has a much higher signal-to-noise ratio for the following reasons: In other words, (i) spatial and electrical isolation of the antenna from the meter box and its components means that noise that may occur if the arc detection antenna is in close proximity to or in the same circuit as meter base components such as current transformers 232A and 232B is reduced, and (ii) the signal is not attenuated by the meter box's high-voltage protection system, such as a MELF resistor. As a result, the meter box of this disclosure provides more accurate arc detection compared to the system of International Publication No. 2021 / 154728.

[0056] Figure 5A illustrates a detailed example of a portion of the circuit diagram 500 of this disclosure, showing a wide-range switch-mode power supply (SMPS) for an electric meter. This circuit diagram illustrates two sections, namely, a high-voltage section 501 and a low-voltage section 502 separated by a current transformer such as the current transformer 232A or 232B in Figure 2.

[0057] The high-voltage section 501 includes bypass lines 238A and 238B labeled VA_Line and Neutral, which are directly connected to the supply voltage source (i.e., the high-voltage power line). The circuit diagram further shows resistors 242 and MOV244 corresponding to those in Figure 2, which represent the front-end protection of the SMPS. When high surge voltages occur, such as during a lightning strike, MOV244 clamps the surge voltage to approximately 800-1000V, and resistor 242 protects MOV244 by limiting the surge current within it.

[0058] The circuit diagram further shows bypass lines 238A and 238B between resistor 242 and MOV 244, as well as the arc detection antenna 234A connected to one or more other components of the high-voltage section, so that the voltage on the arc detection antenna 234A is limited in the event of a surge, thereby limiting dielectric breakdown from the antenna.

[0059] The low-voltage section 502 comprises a circuit separated from the high-voltage section by various components of the high-voltage section 501 and the current transformer 232A.

[0060] At least the antenna 234A is provided on the first layer of the multilayer circuit board as described above.

[0061] Figure 5B illustrates a detailed example of a portion of the schematic diagram 503 of this disclosure, showing a portion of an arc detection circuit 262, such as the arc detection circuit 262 of Figure 2, which is at least partially provided on a second layer of a multilayer circuit board. Schematic diagram 503 shows a second antenna 234B adjacent to the first antenna 234A of Figure 5A. As described above, the first antenna 234A and the second antenna 234B are electrically insulated from each other through a layer of material, for example, FR4.

[0062] If an arc discharge occurs in the meter socket, meter, facility, or anywhere along the transmission line and can generate sufficient RF noise to be picked up by the first antenna 234A, the noise is coupled to the second antenna 234B. An average RF noise detector circuit 246 is provided in the arc detection circuit 262. Specifically, when there is sufficiently high RF noise, the average detection voltage becomes high enough to bias transistor 248 of the arc detection circuit 262, thereby turning it on, and as a result, a square pulse is generated along with the rest of the circuit around transistor 250. These pulses can be converted into digital signals and counted, as well as used to drive LED 252 of the arc detection circuit 262 to provide a visual indication of the arc discharge.

[0063] The diagram above depicts a two-phase solution for an electric meter in which two current transformer structures are installed on the electric meter; however, it should be understood that the presented technology can be applied to other types of electric meters as well. For example, a single-phase electric meter may include the current transformer structures presented herein to detect arcs occurring on a single-phase line. Similarly, a three-phase electric meter may include the three current transformer structures presented herein to detect the arc discharge state in each phase.

[0064] While this subject matter has been described in detail with respect to specific embodiments, those skilled in the art will understand that, upon understanding the foregoing, they can readily create variations, modifications, and equivalents to such embodiments. Therefore, it should be understood that this disclosure is presented for illustrative purposes only, not limitation, and does not preclude the inclusion of modifications, variations, or additions to the subject matter that would be readily apparent to those skilled in the art. Indeed, the methods and systems described herein can be embodied in a variety of other forms. Furthermore, various omissions, substitutions, and modifications can be made to the forms of the methods and systems described herein without departing from the spirit of this disclosure. The appended claims and equivalents are intended to encompass such forms or modifications that fall within the scope of this disclosure. [Explanation of Symbols]

[0065] List of reference numbers 100 Utility Box 102 Electric meter 103 Blades 104 Meter Socket 105A, 105B Socket Jaws 180 facilities 190 Power lines 208 Communication Components 210 Measurement circuit 220 meter base 222 Disconnect circuit 224A, 224B terminal pair 226A, 226B conductor 228A, 228B terminals 232A, 232B current transformer 234A, 234B Arc detection antenna 236A, 236B current transformer structure 238A, 238B Bypass Line 240A, 240B Disconnection Switch 250 Measurement Circuits 262 Arc detection circuit 262A Operating Component 300 Electric Meter 302 Base Plate Assembly 304 Housing Assembly 306 Current transformer structure 308 Register Cover 310 Blades 312 Blades Layers of 318A and 318B multilayer circuit boards 319 separation distance 320 Base Plate 323 Surge Protection 324 Conductive Trace

Claims

1. An electric meter for detecting an electric arc discharge, wherein the electric meter is A base plate assembly comprising a conductor connecting two meter blades, each of which is positioned in a corresponding socket jaw of a meter socket in a utility box connected to a power line, thereby electrically connecting the electric meter to the meter socket; A housing assembly configured to be coupled to the base plate assembly, wherein the housing assembly is A multilayer circuit board, A first layer hosting a first arc detection antenna for emitting a signal indicating an electric arc discharge, A second layer hosting a second arc detection antenna for receiving the aforementioned signal, A housing assembly comprising a multilayer circuit board having, An electric meter equipped with the following features.

2. The electric meter according to claim 1, wherein the multilayer circuit board comprises a third layer containing an insulating material between the first layer and the second layer.

3. The electric meter according to claim 1 or 2, wherein the multilayer circuit board is spatially separated from the base plate assembly.

4. The electric meter according to claim 3, further comprising a bypass line configured to electrically couple the first layer of the multilayer circuit board to a circuit including the power line through the meter socket.

5. The electric meter according to claim 3 or 4, wherein the first antenna is configured to emit the signal indicating an electric arc discharge when the electric arc discharge occurs in the circuit having the bypass line.

6. The electric meter according to any one of claims 3 to 5, wherein the first arc detection antenna is configured to emit the signal in response to a voltage pulse in the bypass line indicating the electric arc discharge.

7. The electric meter according to any one of claims 4 to 6, wherein the bypass line is electrically coupled to the first antenna through a surge protection element.

8. The electric meter according to claim 7, wherein the surge protection element comprises a metal oxide varistor (MOV) and / or a resistor.

9. The electric meter comprises a current transformer structure comprising a current transformer holder and a current transformer cover that form a sealed space, and a current transformer configured to measure the current supplied to the electric meter, disposed within the sealed space, and inductively coupled to the conductor. The electric meter according to any one of claims 1 to 8, wherein the first arc detection antenna and the second arc detection antenna are located outside the current transformer structure and are spaced apart from the current transformer structure.

10. The electric meter according to any one of claims 1 to 9, wherein the first and / or second arc detection antenna comprises one or more bending elements.

11. The electric meter according to claim 10, wherein the bending of one or more of the bending elements is a 90-degree bend.

12. The electric meter according to claim 11 or 12, wherein the length of one or more of the bending elements is 6 to 7 cm.

13. The electric meter according to any one of claims 1 to 12, wherein the meter blade is a current blade, the conductor is configured to connect the voltage from the meter blade to the multilayer circuit board, and the number of meter blades is 4 or 8.

14. An arc detection circuit for an electric meter, the electric meter comprising: a base plate assembly having conductors to which meter blades are connected, each of the meter blades being positioned in a corresponding socket jaw of a meter socket in a utility box connected to a power line to electrically connect the electric meter to the meter socket; and a housing assembly configured to be coupled to the base plate assembly, the arc detection circuit is A multilayer circuit board, A first layer hosting a first arc detection antenna for emitting a signal indicating an electric arc discharge, A second layer hosting a second arc detection antenna for receiving the aforementioned signal, An arc detection circuit comprising a multilayer circuit board equipped with the following features.

15. A method for detecting an electric arc discharge between an electric meter and a meter socket in a utility box connected to a power line, wherein the electric meter comprises: a base plate assembly comprising a conductor for connecting meter blades, each of which is positioned in a corresponding socket jaw of the meter socket to electrically connect the electric meter to the meter socket; and a housing assembly configured to be coupled to the base plate assembly, the housing assembly comprising a multilayer circuit board comprising a first layer for hosting a first arc detection antenna and a second layer for hosting a second arc detection antenna, wherein the method is Using the first arc detection antenna, a signal indicating an electric arc discharge is emitted, The second arc detection antenna is used to receive the signal indicating an electric arc discharge, The electric arc discharge is detected using an arc detection circuit, Methods that include...

16. The method according to claim 15, wherein the multilayer circuit board comprises a third layer containing an insulating material between the first layer and the second layer.

17. The method according to claim 15 or 16, wherein the multilayer circuit board is spatially separated from the base plate assembly.

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