High-voltage electrical connector with limited arc risk in high-frequency alternating operation

Abstract

The present invention relates to an electrical connector (10, 11) having: - a body (12, 21) made of a conductive material, - at least one electrical conductor (13, 23) covered with an electrically insulating material layer (15, 25), - at least one electrical terminal (16, 26) electrically connected to one end of the electrical conductor (13, 23), and - an insulating insert (18, 28) intended to electrically insulate the electrical terminal (16, 26) relative to the body (12, 21) of the electrical connector (10, 11), - the insulating insert (18, 28) having a first electrical continuity region (31.1) covered with a conductive material layer (32, 34) to provide electrical continuity with the body (12, 21), and - a second electrical continuity region (31.2) covered with a conductive material layer (33, 34) to provide electrical continuity with the electrical terminal (16, 26), - an elastic seal (40) arranged in a space (41) in which the air volume inside the electrical connector (10, 11) may be subject to a potential difference between the potential of the body (12, 21) and the potential of the electrical terminal (16, 26), - the elastic seal (40) being in contact with the first electrical continuity region (31.1) and the second electrical continuity region (31.2).

Description

Technical Field

[0001] The present invention relates to a high-voltage electrical connector having a limited risk of arcing during high-frequency alternating operation. The present invention has found a particularly advantageous but non-exclusive application in which the connector is used in the electrical power grid of an aircraft. Background Art

[0002] Figure 1 A schematic view of a component of a male electrical connector 10 and a female electrical connector 11 used in an aircraft electrical network according to the prior art is shown.

[0003] The male electrical connector 10 includes a body 12 made of a conductive material, an electrical conductor 13 covered with an electrically insulating material layer 15, a male electrical terminal 16, and an insulating insert 18 for electrically insulating the male electrical terminal 16 from the body 12.

[0004] The female electrical connector 11 includes a body 21 made of a conductive material, an electrical conductor 23 covered with an electrically insulating material layer 25, a female electrical terminal 26, and an insulating insert 28 for electrically insulating the female electrical terminal 26 from the body 21.

[0005] The increased electrification of aircraft has led to an increase in the voltage applied to the actuation system in order to minimize the mass and electrical losses of the actuation system. The voltage achieved on the electrical power grid is at a level of approximately 800 V, and the maximum DC voltage is close to 1000 V.

[0006] To support the high voltage level, it is known to increase the thickness of the solid dielectric of the electrical connector made of a thermoplastic or thermosetting material. However, ambient air contributes to the electrical insulation between different equipotential regions.

[0007] Figure 2 An equivalent diagram of the dielectric chain between two equipotential regions (e.g., the electrical conductors 13, 23 and the bodies 12, 21 of the electrical connectors 10, 11) is shown. C S and R S respectively represent the capacitance and resistance of the solid dielectric. Cg and Rg respectively represent the capacitance and resistance of the gas dielectric (e.g., ambient air).

[0008] In DC (direct current) operation, the distribution of the electric potential is achieved only by the inherent resistance in the insulator (capacitors are not involved). In addition, the resistivity of the solid dielectric is much higher than that of air. In fact, the voltage is largely distributed in the solid insulator sized to withstand the voltage.

[0009] In AC (alternating current) operation, the distribution of the electric potential is mainly achieved by the inherent capacitors in the insulator, especially when the frequency is high, compared to resistors. These capacitors are sized in farads and their values are defined by the relative surface area, the distance between equipotential regions, the permittivity of vacuum (ε0), and the relative permittivity of the dielectric (εr).

[0010] The value of the capacitor is given by the relation C = S ε0εr / L:

[0011] - C is the value of the capacitor in farads,

[0012] - S is the relative surface area in m 2 2,

[0013] - L is the distance between the opposing surfaces in m, and

[0014] - ε0 is the permittivity of vacuum = 8,854 × 10–12 F / m. The relative permittivity of air is close to 1, while that of the solid dielectrics commonly used is between 3 and 5.

[0015] In AC operation, most of the voltage variations are applied to air, whose dielectric strength is much lower (20 to 50 times) than that of solid dielectrics (1 kV / mm to 3 kV / mm for air and 20 kV / mm to 150 kV / mm for solid dielectrics).

[0016] Under these conditions, ionization of air is observed, which causes a risk of arcing. In particular, this phenomenon occurs during the remote power supply of a polyphase motor via a PWM (pulse width modulation) voltage signal, which exhibits a significant voltage-time variation (dV / dt) due to short switching times and high voltages. This results in power losses and heat dissipation that can deteriorate the solid dielectric in the electrical connector. Summary of the Invention

[0017] The object of the present invention is to effectively solve the above-mentioned drawbacks by providing an electrical connector comprising:

[0018] - a body made of a conductive material,

[0019] - at least one electrical conductor covered with an electrically insulating material layer,

[0020] - at least one electrical terminal electrically connected to one end of the electrical conductor, and

[0021] - an insulating insert for electrically insulating the electrical terminal from the body of the electrical connector,

[0022] - The insulating insert includes a first electrical continuity region covered with a layer of conductive material ensuring electrical continuity with the body, and

[0023] - A second electrical continuity region covered with a layer of conductive material ensuring electrical continuity with the electrical terminal,

[0024] - An elastic washer disposed in a gap in which the internal air volume of the electrical connector may be subject to a potential difference between the potential of the body and the potential of the electrical terminal,

[0025] - The elastic washer is in contact with the first electrical continuity region and the second electrical continuity region.

[0026] Thus, the present invention allows the removal of the ambient air used as electrical insulation inside the connector by minimizing or even eliminating a significant potential difference that may be applied to the air inside the electrical connector. Thus, the present invention minimizes the risk of arcing when the electrical connector is used for high-frequency and high-voltage operations.

[0027] According to one embodiment of the present invention, the elastic washer is made of a silicone resin material.

[0028] According to one embodiment of the present invention, the conductive material layers in the first electrical continuity region and the second electrical continuity region are solid layers.

[0029] According to one embodiment of the present invention, the conductive material layers in the first electrical continuity region and the second electrical continuity region are mesh layers.

[0030] According to one embodiment of the present invention, the conductive material layers in the first electrical continuity region and the second electrical continuity region are made of carbon.

[0031] According to one embodiment of the present invention, the conductive material layers in the first electrical continuity region and the second electrical continuity region are made of metal.

[0032] According to one embodiment of the present invention, the conductive material layers in the first electrical continuity region and the second electrical continuity region each have a thickness between 20 nm and 100 nm.

[0033] According to one embodiment of the present invention, the electrical conductor and the electrical insulation material layer are covered by a shield.

[0034] According to one embodiment of the present invention, the electrical connector is male and / or female.

[0035] The present invention also relates to an assembly of two connectors. Description of the Drawings

[0036] The present invention will be better understood by reading the following detailed description, and other features and advantages will become apparent. The detailed description includes embodiments given by way of illustration with reference to the accompanying drawings, which are presented in a non - limiting example and can be used to complete the understanding of the description of the present invention and its implementation, and ultimately contribute to its definition, wherein:

[0037] Figure 1 already described Figure 1 is a schematic diagram of a component of a male electrical connector and a female electrical connector according to the prior art;

[0038] Figure 2 already described Figure 2 shows an equivalent diagram of a dielectric chain between two equipotential regions in an electrical connector according to the prior art;

[0039] Figure 3 Figure 3 is a schematic diagram of a component of a male electrical connector and a female electrical connector according to the present invention;

[0040] Figure 4a Figure 4b Figure 4a and Figure 4b respectively show top views of conductive material layers on insulating inserts having a solid configuration and a mesh configuration;

[0041] Figure 5 Figure 5 is a schematic diagram of the voltage gradient distribution inside an elastic washer of an electrical connector according to the present invention;

[0042] Figure 6a Figure 6a is a schematic diagram of a male - female electrical connector according to the present invention;

[0043] Figure 6b Figure 6b is a schematic diagram of a component of two male - female electrical connectors according to the present invention. DETAILED DESCRIPTION

[0044] It should be noted that common structural elements and / or functional elements of different embodiments have the same reference numerals. Therefore, unless otherwise stated, these elements have the same structural characteristics, dimensional characteristics, and material characteristics.

[0045] Figure 3 Shows a male electrical connector 10 establishing electrical contact with a female electrical connector 11. The electrical connectors 10 and 11 can be used, for example, in a high - voltage electrical network in an aircraft.

[0046] ​​​​​​​​​​​​​The male electrical connector 10 includes a body 12 made of a conductive material and provided with at least one conductor channel opening 14. The body 12 of the male electrical connector 10 has a shape complementary to the shape of the body 21 of the female electrical connector 11. At least one electrical conductor 13 is inserted into the conductor channel opening 14. The electrical conductor 13 can be made of a conductive material, such as copper, aluminum, or any other conductive material suitable for the application. If desired, the electrical conductor 13 can be covered with a thin decorative layer for improving its conductivity, such as a layer of palladium, gold, silver, tin, nickel, or any other conductive material suitable for the application.

[0047] The electrical conductor 13 can be composed of a single wire having a circular cross-section, a flat surface, or any other form suitable for the application. Alternatively, the electrical conductor 13 can be of the stranded type, i.e., it can be composed of multiple wires arranged side by side. The electrical conductor 13 is covered by an electrically insulating material layer 15. The electrically insulating material of the layer 15 can be constituted by a dielectric sheath covering the electrical conductor 13 or may be constituted by an enamel layer.

[0048] The electrical conductor 13 and the electrically insulating material layer 15 are covered by a shielding portion 19. The shielding portion 19 is made of a conductive material. The shielding portion 19 is electrically connected to the body 12 of the male electrical connector 10.

[0049] At least one male electrical terminal 16 is electrically connected to one end of the electrical conductor 13. The connection between the male electrical terminal 16 and the electrical conductor 13 can be achieved by crimping, welding (with or without adding material), or any other electrical connection technique suitable for the application. The male electrical terminal 16 has a shape complementary to the shape of the female electrical terminal 26.

[0050] An insulating insert 18 is provided for electrically insulating the male electrical terminal 16 from the body 12 of the electrical connector 10. The insulating insert 18 also has the function of holding the male electrical terminal 16 electrically. The insulating insert 18 is arranged within a housing 20 in the body 12. The insulating insert 18 extends at least partially around the male electrical terminal 16. The insulating insert 18 has a shape complementary to the shape of the insulating insert 28 of the female electrical connector 11. The insulating insert 18 can be made of any rigid dielectric material, such as a thermoplastic material or a thermosetting material.

[0051] The insulating insert 18 includes a first electrical continuity region 31.1 and a second electrical continuity region 31.2. The first electrical continuity region 31.1 is covered with a conductive material layer 32 ensuring electrical continuity with the body 12 of the electrical connector, and the second electrical continuity region 31.2 is covered with a conductive material layer 33 ensuring electrical continuity with the male electrical terminal 16.

[0052] The first electrically continuous region 31.1 and the second electrically continuous region 31.2 are different from each other, i.e., there is no material continuity between the conductive material layer 32 of the first electrically continuous region 31.1 and the conductive material layer 33 of the second electrically continuous region 31.2.

[0053] In addition, the female electrical connector 11 includes a body 21 made of a conductive material and provided with at least one conductor channel opening 24. The body 21 of the female electrical connector 11 has a shape complementary to the shape of the body 12 of the male electrical connector 10. At least one electrical conductor 23 is inserted into the conductor channel opening 24. The electrical conductor 23 can be made of a conductive material, such as copper, aluminum, or any other conductive material suitable for the application. If necessary, the electrical conductor 23 can be covered with a thin decorative layer for improving its conductivity, such as a layer of palladium, gold, silver, tin, nickel, or any other conductive material suitable for the application.

[0054] The electrical conductor 23 can be composed of a single metal wire having a circular cross-section, a flat surface, or any other shape suitable for the application. Alternatively, the conductor can be of the stranded type, i.e., it can be composed of multiple metal wires arranged side by side. The electrical conductor 23 is covered with an electrically insulating material layer 25. The electrically insulating material of the layer 25 can be constituted by a dielectric sheath covering the electrical conductor 23 or may be constituted by an enamel layer.

[0055] The electrical conductor 23 and the electrically insulating material layer 25 are covered by a shielding portion 29. The shielding portion 29 is made of a conductive material. The shielding portion 29 is electrically connected to the body 21 of the female electrical connector 11.

[0056] At least one female electrical terminal 26 is electrically connected to one end of the electrical conductor 23. The connection between the female electrical terminal 26 and the electrical conductor 23 can be achieved by crimping, welding (with or without adding material), or any other electrical connection technique suitable for the application. The female electrical terminal 26 has a shape complementary to the shape of the male electrical terminal 16.

[0057] An insulating insert 28 is provided for electrically insulating the female electrical terminal 26 from the body 21 of the electrical connector 11. The insulating insert 28 also has the function of electrically holding the female electrical terminal 26 of the electrical connector 11. The insulating insert 28 is arranged within a housing 30 in the body 21. The insulating insert 28 extends at least partially around the female electrical terminal 26. The insulating insert 28 has a shape that is complementary to the shape of the insulating insert 18 in the male electrical connector 10. The insulating insert 28 can be made of any rigid dielectric material, such as a thermoplastic material or a thermosetting material.

[0058] The insulating insert 28 includes a first electrically continuous region 36.1 and a second electrically continuous region 36.2. The first electrically continuous region 36.1 is covered with a conductive material layer 34 that ensures electrical continuity with the body 21 of the electrical connector 11. The second electrically continuous region 36.2 is covered with a conductive material layer 35 that ensures electrical continuity with the female electrical terminal 26.

[0059] The first electrically continuous region 36.1 and the second electrically continuous region 36.2 are different from each other, that is, there is no material continuity between the conductive material layer 34 of the first electrically continuous region 36.1 and the conductive material layer 35 of the second electrically continuous region 36.2.

[0060] When the male electrical connector 10 and the female electrical connector 11 are assembled together, there is electrical continuity between the first electrically continuous region 31.1 of the male electrical connector 10 and the first electrically continuous region 36.1 of the female electrical connector 11. Electrical continuity may also exist between the second electrically continuous region 31.2 of the male electrical connector 10 and the second electrically continuous region 36.2 of the female electrical connector 11.

[0061] Therefore, the air volume V1 extending radially between the outer surface of the insulating insert 18 and the inner surface of the body 12 is affected by the electric potentials of the bodies 12 and 21 of the electrical connectors 10 and 11 on both sides, which prevents parasitic currents from occurring during high-voltage alternating operation in this region. Similarly, the air volume V2 is affected by the electric potentials of the electrical terminals 16 and 26 of the electrical connectors 10 and 11 on both sides, which prevents parasitic currents from occurring during high-voltage alternating operation in this region.

[0062] As Figure 4a shown, the conductive material layers 32, 33, 34, and 35 of the first electrically continuous regions 31.1, 36.1 and the second electrically continuous regions 31.2, 36.2 can be solid layers.

[0063] Alternatively, as Figure 4b shown, the conductive material layers 32, 33, 34, and 35 of the first electrically continuous regions 31.1, 36.1 and the second electrically continuous regions 31.2, 36.2 can be mesh layers. The mesh layer includes an alternating pattern of empty regions 38 (i.e., regions without any conductive material) and arms 39 that define the mesh of the layer.

[0064] The conductive material layers 32, 33, 34, and 35 of the first electrically continuous regions 31.1, 36.1 and the second electrically continuous regions 31.2, 36.2 are preferably made of carbon. Alternatively, the layers 32, 33, 34, and 35 are made of metal.

[0065] The conductive material layers 32, 33, 34, and 35 can be deposited by ultrasonic welding, plasma deposition, or any other technique for depositing a thin layer of conductive material onto an element made of dielectric material. The type of conductive material is selected based on its compatibility with the material of the insulating inserts 18, 28 onto which the layers 32, 33, 34, and 35 are deposited.

[0066] The conductive material layers 32, 33, 34, and 35 of the first electrical continuity region 31.1 and the second electrical continuity region 31.2 each have a thickness between 20 nm and 100 nm.

[0067] In Figure 3 the elastic washer 40 visible in is arranged in the gap 41, where the internal air volume of the electrical connector may be subject to a potential difference between the potential of the bodies 12, 21 and the potential of the electrical terminals 16, 26. The elastic washer 40 is arranged between the male electrical connector 10 and the female electrical connector 11. The gap 41 extends axially between the insulating insert 18 of the connector 10 and the insulating insert 28 of the connector 11. The gap 41 extends radially between one of the electrical terminals 16 or 26 and one of the insulators 18 or 28.

[0068] The elastic washer 40 is made of a material capable of supporting the maximum internal voltage that the electrical connector can withstand. The elastic washer 40 is preferably made of silicone resin, but any other material suitable for the application is also possible. When the connectors 10 and 11 are assembled together, the elastic washer 40 is compressed to expel the air inside the gap 41. Thus, the air is replaced by the elastic washer 40, which acts as an electrical insulator. Therefore, the elastic washer 40 allows a significant increase in the dielectric strength by a ratio of at least 10 relative to air.

[0069] As can be seen more precisely in Figure 5 the washer 40 contacts the first electrical continuity region 31.1 and the second electrical continuity region 31.2 of the electrical connector 10, in particular one end of the first electrical continuity region 31.1 and one end of the second electrical continuity region 31.2 of the electrical connector 10. The washer 40 also contacts the first electrical continuity region 36.1 and the second electrical continuity region 36.2 of the electrical connector 11, in particular one end of the first electrical continuity region 36.1 and one end of the second electrical continuity region 36.2 of the electrical connector 11.

[0070] On the first face 42 of the gap 41 that defines the air volume, the ends of the first electrical continuity region 31.1 and the second electrical continuity region 31.2 of the electrical connector 10 are held at a distance from each other, for example, a distance on the order of millimeters.

[0071] On the second face 43 defining the air volume of the gap 41, the ends of the first electrical continuity region 36.1 and the second electrical continuity region 36.2 of the electrical connector 11 are kept at a distance from each other, for example, a distance on the order of millimeters.

[0072] In this example, the first face 42 and the second face 43 of the gap 41 are shown, where the ends of the electrical continuity regions are adjacent to each other. Alternatively, the first face 42 and the second face 43 may be opposite to each other.

[0073] Thus, the voltage gradient gradV between the potential of the terminal and the potential of the bodies 12, 21 is distributed inside the elastic washer 40.

[0074] Figure 6a An example of an implementation of the present invention with a male-female electrical connector 50 (i.e., a connector that is a combination of a male connector and a female connector) is shown. This type of connector is used for economies of scale or when the assembly operation on a device (harness or housing) is irreversible to avoid assembly errors.

[0075] More particularly, the electrical connector 50 includes a body 51 made of a conductive material, an electrical conductor 52 covered with an electrically insulating material layer 53, and a shielding portion 54 electrically connected to the body 51. The connector 50 also includes an electrical terminal 55 having a male part and a female part, and an insulating insert 56 for electrically insulating the electrical terminal 55 from the body 51.

[0076] Similar to the foregoing embodiment, the insulating insert 56 includes a first electrical continuity region 57.1 and a second electrical continuity region 57.2. The first electrical continuity region 57.1 is covered with a conductive material layer ensuring electrical continuity with the body 51, and the second electrical continuity region 57.2 is covered with a conductive material layer ensuring electrical continuity with the electrical terminal 55.

[0077] The first electrical continuity region 57.1 and the second electrical continuity region 57.2 are different from each other, that is, there is no material continuity between the conductive material layer of the first electrical continuity region 57.1 and the conductive material layer of the second electrical continuity region 57.2.

[0078] As Figure 6b shown, when two male-female electrical connectors 50 and 50' are assembled together, the male part of the electrical terminal 55 of the connector 50 mates with the female part of the electrical terminal 55 of the connector 50', while the female part of the electrical terminal 55 of the connector 50 mates with the male part of the electrical terminal 55 of the connector 50'.

[0079] There is electrical continuity between the first electrical continuity region 57.1 of the electrical connector 50 and the first electrical continuity region 57.1 of the electrical connector 50'. There is also electrical continuity between the second electrical continuity region 57.2 of the electrical connector 50 and the second electrical continuity region 57.2 of the electrical connector 50'.

[0080] Alternatively, the electrical connectors 10, 11, and 50 are multi-pin connectors including two or more electrical terminals 16, 26, and 55. In this case, electrical continuity regions are provided for each of the electrical terminals 16, 26, and 55 of the electrical connectors 10, 11.

[0081] Of course, the different features, variations, and / or embodiments of the present invention can be associated with each other in various combinations, as long as they are compatible with each other or not mutually exclusive. In addition, the present invention is not limited to the above embodiments, which are provided only as examples. The present invention encompasses various modifications, alternative forms, and other variations that can be conceived by those skilled in the art within the context of the present invention, and in particular, any combination of the above various operating modes can be employed individually or in combination.

Claims

1. An electrical connector (10, 11, 50), the electrical connector (10, 11, 50) comprising: - A body (12, 21), the body (12, 21) being made of a conductive material, - At least one electrical conductor (13, 23), the at least one electrical conductor (13, 23) being covered with an electrically insulating material layer (15, 25), - At least one electrical terminal (16, 26), the at least one electrical terminal (16, 26) being electrically connected to one end of the electrical conductor (13, 23), and - An insulating insert for electrically insulating the electrical terminal (16, 26) from the body (12, 21) of the electrical connector (10, 11), characterized in that the insulating insert includes a first electrical continuity region (31.1), the first electrical continuity region (31.1) being covered with a conductive material layer (32, 34) ensuring electrical continuity with the body (12, 21), and - A second electrical continuity region (31.2), the second electrical continuity region (31.2) being covered with a conductive material layer (33, 35) ensuring electrical continuity with the electrical terminal (16, 26), - An elastic washer (40), the elastic washer (40) being arranged in a gap (41), the gap (41) being configured to extend radially between the insulating insert and the at least one electrical terminal (16, 26) and axially between the insulating insert and the insulating insert of another electrical connector when the other electrical connector is connected to the electrical connector (10, 11, 50), - The elastic washer (40) being in contact with the first electrical continuity region (31.1) and the second electrical continuity region (31.2).

2. The electrical connector according to claim 1, wherein The elastic washer (40) is made of a silicone resin material.

3. The electrical connector according to claim 1, characterized in that, The conductive material layers (32, 33, 34, 35) of the first electrical continuity region (31.1, 36.1) and the second electrical continuity region (31.2, 36.2) are solid layers.

4. The electrical connector according to claim 1, wherein The conductive material layers (32, 33, 34, 35) of the first electrical continuity region (31.1, 36.1) and the second electrical continuity region (31.2, 36.2) are mesh layers.

5. The electrical connector according to any one of claims 1 to 4, characterized in that, The conductive material layers (32, 33, 34, 35) of the first electrical continuity region (31.1, 36.1) and the second electrical continuity region (31.2, 36.2) are made of carbon.

6. The electrical connector according to any one of claims 1 to 4, characterized in that, The conductive material layers (32, 33, 34, 35) of the first electrical continuity region (31.1, 36.1) and the second electrical continuity region (31.2, 36.2) are made of metal.

7. The electrical connector according to any one of claims 1 to 4, characterized in that, Each of the conductive material layers (32, 33, 34, 35) of the first electrical continuity region (31.1, 36.1) and the second electrical continuity region (31.2, 36.2) has a thickness between 20 nm and 100 nm.

8. The electrical connector according to any one of claims 1 to 4, characterized in that, The electrical conductor (13, 23) and the electrically insulating material layer (15, 25) are covered by a shielding portion (19, 29).

9. The electrical connector according to any one of claims 1 to 4, characterized in that, The electrical connector is male and / or female.

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