EP2099105B1 - Improved lightning arrester device for three-phase electric network - Google Patents

Abstract

The device has electrical connections (P4-P6) connecting a connection (K4) and common terminals (BN1, BN2) of respective interchangeable modules (M1, M2) to the terminals (BN1, BN2) and a common terminal (BN3) of an interchangeable module (M3), respectively. Electrical connections (P7-P9) connect ground terminals (BT1-BT3) of the respective modules (M1-M3) to the terminals (BT2, BT3) and a connection (K5), respectively. Electrical connections (P1-P3) connect connections (K1-K3) to phase terminals (BL1-BL3) of the respective modules (M1-M3), respectively. The electrical connections are constituted by insulated conductor wires.

Description

The invention relates generally to the field of electrical protection.

More specifically, the invention relates to a lightning protection device for a three-phase electrical network comprising first, second, and third phase conductors, a neutral conductor and a ground conductor, this device comprising three components of the first type arranged between the three respective phase conductors and the neutral conductor, and at least one second type component disposed between the neutral conductor and the earth conductor.

Such a device, according to the preamble of claim 1, is known to DE 20 2007 014 192 U1 .

The reinforcement of the standards for electrical protection against lightning leads and obliges a priori to reinforce the performance of the second type component which is arranged between the neutral and earth conductors.

The present invention aims to provide a very advantageous alternative to this solution.

• des première, deuxième et troisième liaisons électriques reliant respectivement les première, deuxième, et troisième connexions aux bornes de phase des premier, deuxième, et troisième modules,
• des quatrième, cinquième et sixième liaisons électriques reliant respectivement la quatrième connexion à la borne commune du premier module, la borne commune du premier module à celle du deuxième module, et la borne commune du deuxième module à celle du troisième module, et
• des septième, huitième et neuvième liaisons électriques reliant respectivement la borne de terre du premier module à celle du deuxième module, la borne de terre du deuxième module à celle du troisième module, et la borne de terre du troisième module à la cinquième connexion.

To this end, the device of the invention, moreover, conforming to the generic definition given in the preamble above, is essentially characterized in that it comprises a base and first, second, and third interchangeable modules, in that each module comprises a component of the first type and a component of the second type connected to each other by a common terminal, in that each module has, in addition to the common terminal, a phase terminal and a terminal of respectively constituted by free terminals respective components of the first and second types of this module, in that the base physically supports each of the modules and comprises first, second, third, fourth and fifth connections adapted to connect respectively to the first, second and third phase conductors respectively , to the neutral conductor and to the earth conductor, and in that the base comprises

• first, second and third electrical connections respectively connecting the first, second and third connections to the phase terminals of the first, second and third modules,
• fourth, fifth and sixth electrical connections respectively connecting the fourth connection to the common terminal of the first module, the common terminal of the first module to that of the second module, and the common terminal of the second module to that of the third module, and
• seventh, eighth and ninth electrical connections respectively connecting the earth terminal of the first module to that of the second module, the earth terminal of the second module to that of the third module, and the earth terminal of the third module to the fifth connection.

Thanks to this arrangement, the three modules, which are consumable products, can be identical to each other and can be used interchangeably in a three-phase network and in a single-phase network, which simplifies the management of their stock and streamlines production.

Preferably, the impedances of the fifth and seventh links are substantially equal to each other, this expression applying to impedances having between them only a maximum relative difference of 5%.

Similarly, it is advantageous to ensure that the impedances of the sixth and eighth links are substantially equal to each other.

Each component of the first type preferably has a variable impedance and comprises for example a varistor.

Each component of the second type advantageously has a discontinuously decreasing impedance and comprises for example a spark gap.

The base preferably comprises three multicore jacks in each of which a module is plugged removably.

For example, the base comprises a printed circuit board supporting said connections and tracks constituting said electrical connections.

• la figure 1 est un schéma électrique représentant un dispositif conforme à l'invention;
• la figure 2 est une vue en élévation illustrant un premier mode de réalisation possible d'une embase équipant un dispositif conforme à l'invention et observée du côté de sa face antérieure; et
• la figure 3 est une vue en perspective illustrant un deuxième mode de réalisation possible d'une embase équipant un dispositif conforme à l'invention et observée du côté de sa face postérieure.

Other characteristics and advantages of the invention will emerge clearly from the description which is given hereinafter, by way of indication and in no way limitative, with reference to the appended drawings, in which:

• the figure 1 is an electrical diagram showing a device according to the invention;
• the figure 2 is an elevational view illustrating a first possible embodiment of a base fitted to a device according to the invention and observed on the side of its anterior face; and
• the figure 3 is a perspective view illustrating a second possible embodiment of a base equipping a device according to the invention and observed on the side of its rear face.

As previously announced, the invention relates to a surge protection device for a three-phase electrical network.

Such a network typically comprises figure 1 ) three phase conductors L1, L2, L3, a neutral conductor N and a ground conductor T.

A surge protection device for such a network comprises, in known manner, three components of the first type C11, C12, and C13, arranged between the three respective phase conductors L1, L2, and L3 and the neutral conductor N, and a component of second type C21 disposed between the neutral conductor N and the earth conductor T.

The first type of components, C11, C12, and C13, typically have a variable and decreasing impedance depending on the current flowing through them, and generally consist of a varistor.

The components of the second type, C21, C22, and C23, typically have an impedance that decreases discontinuously as a function of the voltage applied thereto, and are generally each constituted by a spark gap.

The device of the invention comprises a base E and three interchangeable modules M1, M2, and M3, these modules being preferably identical to each other.

Each of these modules M1, M2, and M3 comprises a component of the first type, respectively denoted C11, C12, and C13, and a component of the second type C21, C22, and C23, the components of the first and second types of each module being connected to each other by a common terminal respectively denoted BN1, BN2, and BN3.

In addition to this common terminal BN1, BN2, and BN3, each module M1, M2, and M3 has a phase terminal, respectively denoted BL1, BL2, and BL3, and constituted by the free terminal, that is to say non-common , of the first type component C11, C12, and C13 of this module.

Moreover, each module M1, M2, and M3 has a ground terminal, respectively denoted BT1, BT2, and BT3, and constituted by the free terminal, that is to say non-common, of the component of the second type C21, C22, and C23 of this module.

The base E is designed to physically support each of the modules M1, M2, and M3 and has five connections K1, K2, K3, K4, and K5.

The first three connections K1, K2, and K3 are designed to connect respectively to the three phase conductors L1, L2, and L3.

The fourth connection K4 is adapted to connect to the neutral conductor N, and the fifth connection K5 is adapted to connect to the earth conductor T.

• une première liaison électrique P1 reliant la première connexion K1 à la borne de phase BL1 du premier module M1,
• une deuxième liaison électrique P2 reliant la deuxième connexion K2 à la borne de phase BL2 du deuxième module M2,
• une troisième liaison électrique P3 reliant la troisième connexion K3 à la borne de phase BL3 du troisième module M3,
• une quatrième liaison électrique P4 reliant la quatrième connexion K4 à la borne commune BN1 du premier module M1,
• une cinquième liaison électrique P5 reliant la borne commune BN1 du premier module M1 à la borne commune BN2 du deuxième module M2,
• une sixième liaison électrique P6 reliant la borne commune BN2 du deuxième module M2 à la borne commune BN3 du troisième module M3,
• une septième liaison électrique P7 reliant la borne de terre BT1 du premier module M1 à la borne de terre BT2 du deuxième module M2,
• une huitième liaison électrique P8 reliant la borne de terre BT2 du deuxième module M2 à la borne de terre BT3 du troisième module M3, et
• une neuvième liaison électrique P9 reliant la borne de terre BT3 du troisième module M3 à la cinquième connexion K5.

Furthermore, the base E comprises at least nine electrical connections P1 to P9, namely:

• a first electrical connection P1 connecting the first connection K1 to the phase terminal BL1 of the first module M1,
• a second electrical link P2 connecting the second connection K2 to the phase terminal BL2 of the second module M2,
• a third electrical connection P3 connecting the third connection K3 to the phase terminal BL3 of the third module M3,
• a fourth electrical connection P4 connecting the fourth connection K4 to the common terminal BN1 of the first module M1,
• a fifth electrical connection P5 connecting the common terminal BN1 of the first module M1 to the common terminal BN2 of the second module M2,
• a sixth electrical connection P6 connecting the common terminal BN2 of the second module M2 to the common terminal BN3 of the third module M3,
• a seventh electrical connection P7 connecting the ground terminal BT1 of the first module M1 to the ground terminal BT2 of the second module M2,
• an eighth electrical connection P8 connecting the ground terminal BT2 of the second module M2 to the ground terminal BT3 of the third module M3, and
• a ninth electrical connection P9 connecting the ground terminal BT3 of the third module M3 to the fifth connection K5.

To best balance the load of the components C21 and C22, it is desirable to ensure that the impedances of the fifth and seventh links, P5 and P7, are substantially equal to each other, that is to say that they do not present between them that a relative difference of at most equal to 5% in relative value.

Similarly, in order to balance the load of the components C22 and C23 as well as possible, it is desirable to ensure that the impedances of the sixth and eighth links, P6 and P8, are substantially equal to each other, the optimal equilibrium thus being obtained by giving the same value at the impedances of the links P5, P6, P7 and P8.

As shown by Figures 2 and 3 , the base E is preferably essentially constituted by a printed circuit board supporting the connections K1 to K5, as well as three multicore outlets PM1, PM2, and PM3, in each of which is removably connected a corresponding module M1, M2, or M3.

As shown in figure 2 , the electrical connections P1 to P9 can then be constituted by tracks carried by this printed circuit board.

However, as shown in figure 3 the electrical connections P1 to P9 may also be constituted by insulated conductor wires, for example arranged on the rear face of this printed circuit board.

Claims (10)

1. A lightning protection device for a three-phase electrical system comprising first, second and third phase conductors (L1, L2, L3), a neutral conductor (N) and an earth conductor (T), said device comprising three components of a first type (C11, C12, C13) disposed between the three respective phase conductors (L1, L2, L3) and the neutral conductor (N), and at least one component of a second type (C21) disposed between the neutral conductor (N) and the earth conductor (T), characterized in that it comprises a base (E) and first, second and third interchangeable modules (M1, M2, M3), in that each module (M2, M2, M3) comprises a component of the first type (C11, C12, C13) and a component of the second type (C21, C22, C23) connected to one another by a common terminal (BN1, BN2, BN3), in that, apart from the common terminal (BN1, BN2, BN3), each module (M1, M2, M3) has a phase terminal (BL1, BL2, BL3) and an earth terminal (BT1, BT2, BT3) respectively formed by respective free terminals of the components of the first type (C11, C12, C13) and of the second type (C21, C22, C23) of this module (M1, M2, M3), in that the base (E) physically supports each of the modules (M1, M2, M3) and has first, second, third, fourth and fifth connections (K1, K2, K3, K4, K5) suitable for respectively linking up with the first, second and third phase conductors (L1, L2, L3), the neutral conductor (N) and the earth conductor (T), and in that the base (E) has:

   - first, second and third electrical connections (P1, P2, P3) respectively connecting the first, second and third connections (K1, K2, K3) to the phase terminals (BL1, BL2, BL3) of the first, second and third modules (M1, M2, M3),

   - fourth, fifth and sixth electrical connections (P4, P5, P6) respectively connecting the fourth connection (K4) to the common terminal (BN1) of the first module (M1), the common terminal (BN1) of the first module (M1) to that (BN2) of the second module (M2), and the common terminal (BN2) of the second module (M2) to that (BN3) of the third module (M3), and

   - seventh, eighth and ninth electrical connections (P7, P8, P9) respectively connecting the earth terminal (BT1) of the first module (M1) to that (BT2) of the second module (M2), the earth terminal (BT2) of the second module (M2) to that (BT3) of the third module (M3), and the earth terminal (BT3) of the third module (M3) to the fifth connection (K5).
2. A device according to Claim 1, characterized in that the impedances of the fifth (P5) and seventh (P7) connections are substantially equal to one another.
3. A device according to any one of the preceding claims, characterized in that the impedances of the sixth (P6) and eighth (P8) connections are substantially equal to one another.
4. A device according to any one of the preceding claims, characterized in that each component of the first type (C11, C12, C13) has a variable impedance.
5. A device according to any one of the preceding claims, characterized in that each component of the first type (C11, C12, C13) comprises a varistor.
6. A device according to any one of the preceding claims, characterized in that each component of the second type (C21, C22, C23) intermittently exhibits a decreasing impedance.
7. A device according to any one of the preceding claims, characterized in that each component of the second type (C21, C22, C23) comprises a spark gap.
8. A device according to any one of the preceding claims, characterized in that the three modules (M1, M2, M3) arc identical.
9. A device according to any one of the preceding claims, characterized in that the base (E) comprises three multiconductive sockets (PM1, PM2, PM3), into each of which a module (M1, M2, M3) is removably plugged in.
10. A device according to any one of the preceding claims, characterized in that the base (E) comprises a printed circuit board bearing said connections (K1 to K5) and tracks forming said electrical connections (P1 to P9).

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