Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H83/00—Protective switches, e.g. circuit-breaking switches, or protective relays operated by abnormal electrical conditions otherwise than solely by excess current
  • H01H83/10—Protective switches, e.g. circuit-breaking switches, or protective relays operated by abnormal electrical conditions otherwise than solely by excess current operated by excess voltage, e.g. for lightning protection
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
  • H01H9/14—Adaptation for built-in safety spark gaps
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T29/00—Metal working
  • Y10T29/49—Method of mechanical manufacture
  • Y10T29/49002—Electrical device making
  • Y10T29/49105—Switch making

Definitions

• the present invention relates to the general technical field of devices for protecting equipment or electrical installations against electrical disturbances, such as transient overvoltages due to a lightning strike.
• the present invention relates more particularly to a protection device of an electrical installation intended to be mounted in shunt with respect to the electrical installation and comprising at least two electrically conductive contact members capable of passing from a closed position to a position opening when the protective device is traversed by a current of intensity greater than a predetermined threshold value.
• the invention also relates to a method of manufacturing a protection device of an electrical installation, said protection device comprising at least two electrically conductive contact members capable of passing from a closed position to an open position when the protective device is traversed by a current of intensity greater than a predetermined threshold value.
• the invention finally relates to a new use of overcurrent protection devices.
• an overvoltage protection device such as spark gap arrester
• an overcurrent protection device mounted in series with an overcurrent protection device, of the circuit breaker type.
• the circuit breaker then makes it possible to isolate the surge arrester in the event of a failure of the latter, while avoiding the opening of the other general cut-off devices of the electrical installation, in order to ensure continuity of service of the power supply.
• such assemblies generally involve taking into account, in order to achieve the level of protection of the desired installation, not only the protection level of the arrester but also the own impedance of the circuit breaker.
• the surge arrester and the circuit breaker are sometimes located at a distance from each other and the impedance of the connecting conductors is often difficult, if not impossible to calculate precisely, which can lead to errors and an underestimation of the actual level of protection of the electrical installation.
• the objects assigned to the invention therefore aim to propose a new protection device for an electrical installation that does not have the drawbacks listed above and that can be obtained from standard components, without fundamentally modifying the structure of the protection device. , of the circuit breaker type, known.
• Another object of the invention is to provide a new protection device to ensure a certain level of protection of the electrical installation, while minimizing the number of components necessary for its implementation.
• Another object of the invention is to propose a new protective device that can be effectively isolated from the electrical installation when it is subjected to overcurrent.
• Another object of the invention is to propose a new protection device which is particularly easy to install.
• Another object of the invention is to propose a new protection device whose operating state can be easily monitored.
• the objects assigned to the invention also aim at proposing a new method for perfecting a protection device of an electrical installation making it possible, simply and with the aid of standard components, to improve the performance of the device.
• Another object of the invention is to provide a novel method of improving a protection device to improve the functionality of the latter.
• Another object of the invention is to provide a novel method of improving a protection device to improve the control of the level of protection offered by the device.
• the objects assigned to the invention are also intended to propose a new use of an overcurrent protection device to confer on the latter additional protection functions.
• the objects assigned to the invention are achieved by means of a protection device of an electrical installation intended to be mounted in shunt with respect to the electrical installation and comprising at least two electrically conductive contact members capable of passing from a closed position to an open position when the protective device is traversed by a current of intensity greater than a predetermined threshold value, characterized in that in the closed position, the contact members are separated; one from the other by a potentially insulating piece, thus forming a spark gap protection against overvoltages between the contact members.
• the objects assigned to the invention are also achieved by means of a method of manufacturing a protection device of an electrical installation, said protection device comprising at least two electrically conductive contact members capable of passing from a closed position at an open position when the protective device is traversed by a current of intensity greater than a predetermined threshold value, characterized in that the method comprises a step of mounting a potentially insulating piece between the organs contact, so that in the closed position, the contact members are separated by said potentially insulating piece, thereby forming a spark gap protection against overvoltages between the contact members.
• an overcurrent protection device as an overvoltage protection device by interposing a potentially insulating piece between the contact members of the device.
• overcurrent protection device for forming an overvoltage protection spark gap between said contact members.
• FIG. 1 illustrates, with the aid of a simplified electrical diagram, the principle of the protection device according to the invention in a first position, called closure.
• FIG. 2 illustrates, with the aid of a simplified electrical diagram, the protection device according to the invention shown in Figure 1 in its open position.
• FIG. 3 illustrates, in a detailed schematic view, the protective device according to the invention in its closed position.
• FIG. 4 illustrates, in a detailed schematic view, the protective device according to the invention in its open position.
• the protective device 1 according to the invention is illustrated in Figures 1 to 4. It is intended to be mounted in parallel (or parallel) with respect to an electrical installation 2 for the purpose of protecting it.
• electrical installation refers here to any type of device or network that can be powered by an electric current.
• the protection device 1 according to the invention is advantageously intended to be disposed between a phase P of the installation 2 to be protected and the T. It is also conceivable, without departing from the scope of the invention, that the protective device 1, instead of being connected bypass between a phase P and the earth T, is connected between the neutral and the earth, between a phase and the neutral, or between two phases (case of a differential protection).
• the protective device 1 according to the invention is advantageously connected to the electrical installation 2 by wiring, at connection terminals 5, 6.
• the protective device 1 comprises at least two contact members 3, 4, electrically conductive, and preferably metallic, which are capable of occupying at least two distinct positions, and in particular of passing from a so-called closing position to a so-called opening position when the protection device 1 is traversed by a current I of intensity greater than a predetermined threshold value.
• the closed position corresponds to the functional position of the protection device 1, in which it is connected to the electrical installation 2 and able to protect it.
• the open position, illustrated in FIG. 2, corresponds on the contrary to an off state, in which the protection device 1 is no longer connected to the electrical installation 2 and is therefore no longer able to protect it. .
• the disconnection is effected by relative spacing of the contact members 3, 4, so as to increase the isolation distance between them, in the manner of a circuit breaker.
• the protection device 1 comprises at least one movable contact member 3, able to move between the closed position and the aforementioned open position, and connected, preferably directly, to one of the connection terminals 5, for example by means of a flexible connector 20 allowing its mobility.
• the protective device 1 also preferably comprises a fixed contact member 4 which, during the transition from the closed position to the open position, preferably remains stationary.
• the protection device 1 comprises a triggering mechanism 7, sensitive to the intensity of the current I passing through it and able to trigger, when the intensity of the current I exceeds the predetermined threshold value mentioned above, the opening of the contact members. 3, 4.
• the triggering mechanism 7 comprises means 8 for detecting overcurrents, arranged in series between one of the contact members, for example the fixed contact member 4, and one of the connection terminals 6 of FIG. to be traversed substantially by the same current that is passed by the protection device 1.
• the detection means 8 may advantageously comprise a bimetallic strip 11 and / or an induction coil 9, wound around a plunger core 10 Such means being conventionally used in circuit breakers and well known to those skilled in the art, they are not the subject of a more detailed description.
• the detection means 8 are preferably in kinematic connection with an actuating mechanism 12 capable of controlling the displacement of the movable contact member 3 between the closed position and the open position when an overcurrent is detected by the 8.
• an actuating mechanism 12 capable of controlling the displacement of the movable contact member 3 between the closed position and the open position when an overcurrent is detected by the 8.
• the thermal effects related to the passage of high current I cause bending of the bimetallic strip 11 which in turn actuates or triggers the actuating mechanism 12 ( Figure 4).
• the magnetic effects related to the passage of the current I in the induction coil 9 cause the displacement of the plunger 10 which in turn actuate the actuating mechanism 12.
• the actuating mechanism 12 advantageously comprises a movable support 13 secured to the movable contact member 3 and held in the closed position illustrated in Figure 3 under the constraint of an elastic return means 14 of the spring type.
• the mobile support 13 is released and moves, for example in translation, under the impulse of the elastic restoring force F exerted by the elastic means 14, causing with it the movable contact member 3 which deviates from the fixed contact member 4 by a predetermined isolation distance d.
• the contact members 3, 4 are, in their closed position, separated from each other by a potentially insulating piece.
• the part 15 is thus advantageously interposed between the contact members 3, 4 so that in the closed position, the contact members 3, 4 come into abutment and in physical contact with the part 15.
• the part 15 has the function of maintaining contact members 3, 4 to distance from each other so that in the closed position illustrated in Figure 3, the contact members 3, 4 are separated by a gap, thereby forming a spark gap E of protection against overvoltages between the organs of contact 3, 4.
• the spark gap E here denotes the dielectric medium 17 separating, in the closed or open position, the contact members 3, 4 and within which an electric arc 16 is likely to form, said electric arc 16 corresponding to the ionization of the dielectric medium 17.
• the width of the gap, and in particular of the spark gap E is thus advantageously predetermined by the width of the part 15 so that in case of overvoltage exceeding a predetermined value, an electric arc 16 is formed between the contact members 3, 4 and thus flows the overvoltage current to earth.
• potentially insulating is meant the property of certain materials capable of passing, when their maximum flow capacity is reached, from a conducting state to an insulating state in which they limit, in the manner of 'an insulator, the passage of the current.
• materials include conventional dielectric materials, such as ceramics, but also materials based on metal oxide, for example zinc oxide, such as semiconductor materials.
• potentially insulating materials are, in the sense of the invention, obviously less conductive than metals.
• the contact members 3, 4 thus form, in the closed position, the electrodes of the spark gap E and the protection device 1 according to the invention then combines an overvoltage protection function, by means of the spark gap E, and an overcurrent protection function, via the movable contact member 3.
• the spark gap E thus forms an overvoltage protection element, arranged physically between the contact members 3, 4 and connected electrically, in the position closing, to the electrical installation 2 so as to protect it against overvoltages.
• the movable contact member 3 is advantageously mounted so as to come, in the closed position, in abutment with the potentially insulating piece.
• the potentially insulating piece 15 is made of dielectric material, for example ceramic.
• the part 15 is made of semiconductor material, and advantageously constitutes a varistor.
• the protection device 1 then constitutes a two-stage protection device, namely a thin protection stage, and a coarse protection stage.
• the surge current flows through the varistor, which then forms a conductive bridge between the contact elements 3, 4 and the protection of the electrical installation 2.
• an electric arc 16 is formed between the contact members 3, 4 and bypasses the varistor, the spark gap E then forming the protection element of the electrical installation 2.
• the contact members 3, 4 are, in the closed position, separated by the dielectric medium 17 preferably fluid and formed by a gas such as air, and the part 15 is arranged between the contact members 3, 4 so that in case of overvoltage exceeding a predetermined value, the electric arc 16 is initiated in the dielectric medium 17, substantially at the interface with the part 15.
• the electric arc 16 is thus formed advantageously along the part 15, the zone located in the dielectric medium 17, close to said part 15, then constituting the spark gap of the spark gap E.
• the potentially insulating part thus advantageously forms a triggering aid for the spark gap E, making it possible to better control the triggering of the latter and thus the level of protection offered by the protective device 1.
• the piece 15 makes it possible in particular to avoid use a more complex triggering system, such as a trip circuit, whose integration within a known protection device would require a profound change in its structure and would also lead to an increase in congestion of the device.
• the protection device 1 comprises a device 18 for breaking the electric arc 16.
• the cut-off device 18 is formed by an arrangement of metal plates 19 mounted in parallel and able to split the electric arc 16 from the spark gap E in a plurality of elementary arcs so as to cause its extinction.
• the cutoff device 18 is advantageously arranged at the outlet of the spark gap E, that is to say at the ends of the contact members 3, 4 opposite to the priming zone.
• the cut-off device 18 and the contact elements 3, 4 are thus arranged in such a way that, when the contact elements 3, 4 are opened, the electric arc 16 is driven towards the cut-off device 18.
• the cut-off device 18, and in particular the metal splitting plates 19 preferably extend in a direction XX 'substantially perpendicular to the longitudinal extension direction YY' of the members contact 3, 4.
• the protection device 1 according to the invention is integrated within a housing in the form of a plug-in cartridge on a base (not shown). This embodiment thus facilitates maintenance and in particular the replacement of the device.
• the protection device 1 also preferably comprises indicating means (not shown) of the state of the device.
• indicating means are particularly suitable for preventing third parties, for example by virtue of appropriate visual information, that the protection device 1 is out of service and disconnected from the electrical installation 2.
• Such indicating means are advantageously connected functionally, and preferably mechanically, to the movable contact member 3 so that the movement of the movable contact member 3 from its closed position to its open position actuates the state indicating means protection device 1.
• the invention also relates to a method of manufacturing a protection device 1 of an electrical installation, the protection device 1 comprising at least two electrically conductive contact members 3, 4 capable of passing from a closed position to an open position when the protective device 1 is traversed by a current I of intensity greater than a predetermined threshold value, the method comprising a step of mounting a potentially insulating part between the contact members 3, 4, such that in the closed position, the contact members 3, 4 are separated by said potentially insulating piece, thereby forming a spark gap against overvoltages between the contact members 3, 4.
• the step (a) of assembly thus advantageously comprises a phase of separation of the contact members 3, 4, during which one comes position the potentially insulating piece 15 between the contact members 3, 4, so as to keep the latter at a distance from one another in the closed position.
• the protective device 1 Before the mounting step (a), the protective device 1 can thus be formed by a pre-existing overcurrent protection device, of the circuit-breaker type, which has just been transformed into an overvoltage protection device. type of surge arrester, simply by interposing the potentially insulating part 15 between the contact members 3, 4.
• the step (a) for mounting then consists in modifying the overcurrent protection device to turn it into a surge protection device .
• Such a method makes it possible to improve the functionality of the overcurrent protection device without modifying it in a fundamental way. It is therefore possible, by means of the process according to the invention, to modify overcurrent protection devices, of the circuit-breaker type, already in place in electrical equipment or installations, so as to give them an additional function. overvoltage protection.
• the method according to the invention thus makes it possible to avoid expensive replacement of devices already in place.
• the invention also relates to the use of a potentially insulating piece to form a spark gap E protection against overvoltages between the contact members 3, 4 separable from an overcurrent protection device.
• the potentially insulating piece 15 is advantageously interposed between the contact members 3, 4.
• the present invention furthermore relates to the use of an overcurrent protection device 1, of the breaker type, as an overvoltage protection device, in which a potentially insulating piece 15 is interposed between the contact members 3, 4 of overcurrent protection device, for forming a spark gap E for protection against overvoltages between said contact members 3, 4.
• the protection device 1 is initially in its service configuration illustrated in FIG. 3.
• an electric arc 16 is formed along the piece 15 in the air between the contact members 3, 4.
• the electric arc 16 then flows the current I corresponding to the overvoltage, for example to earth, and thus ensures the protection of the electrical installation 2 by deriving this current.
• the detection means 8 sensitive to this overcurrent, trigger the actuating mechanism 12 which acts on the movable contact member 3 so as to cause it to move under elastic stress towards its open position. In this open position, the contact members 3, 4 are separated by an isolation distance d sufficient to prevent the maintenance and reformation of an electric arc.
• the electric arc 16 initially formed is then driven, upon opening of the contact members 3, 4, towards the outlet of the spark gap E and to the cut-off device 18, advantageously formed by a fractionation chamber.
• the V shape of the contact members 3, 4 during their opening then contributes to driving the electric arc 16 more rapidly towards the cut-off device 18.
• the splitting of the electric arc 16 within the cut-off device 18 ensures its extinction, and the protective device 1 is then permanently disconnected from the rest of the electrical installation 2 and must be replaced.
• Indication means of visual type, then allow the operator to report the failure of protection device 1, and take the necessary measures to replace it quickly.
• the protection device 1 therefore constitutes a surge arrester with an integrated circuit breaker which only requires, for its realization, to modify succinctly and simply conventional circuit breakers.
• protection device 1 allows, because of its one-piece character, to limit the risk of error in the choice of the type of circuit breaker to be associated with a given arrester.
• Another advantage of the invention is to gather, within a single unit block, two different functionalities, namely overvoltage protection and overcurrent protection.
• the invention finds its industrial application in the manufacture of protective devices for equipment or electrical installations.

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• 2004
  • 2004-12-03 FR FR0412881A patent/FR2879033B1/fr not_active Expired - Fee Related
• 2005
  • 2005-12-02 US US11/720,660 patent/US20100027182A1/en not_active Abandoned
  • 2005-12-02 EP EP05824644A patent/EP1820200A1/de not_active Withdrawn
  • 2005-12-02 CN CN200580041460.8A patent/CN100578713C/zh not_active Expired - Fee Related
  • 2005-12-02 WO PCT/FR2005/003001 patent/WO2006059011A1/fr active Application Filing

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