Limiter pole for an electrical switch and DC electrical switch comprising the limiter pole

Abstract

A limiter pole (B) for a multi-pole DC electrical switch (2) comprises a compartment in which an input terminal and an output terminal for direct current are arranged, together with a first electrical contact connected to the input terminal and a second electrical contact connected to the output terminal, a third and a fourth electrical contact connected in series with each other, the third and the fourth contacts being movable simultaneously relative to the first and the second electrical contacts between a closed position and an open position, respectively, in which the first and the third contacts and the second and the fourth contacts are in contact with each other to allow direct current to flow between the input terminal and the output terminal, and in which the contacts are away from each other to interrupt the flow of current between the input terminal and the output terminal. The limiter pole (B) comprises: a first arc forming chamber in which the first and the third electrical contacts are placed; a second arc forming chamber in which the second and the fourth electrical contacts are placed; and first and second arc extinguishing chambers, which are respectively associated with the first and the second arc forming chambers.

Description

Technical Field

[0001] The present invention relates to a limiter pole for an electrical switch and a DC electrical switch comprising the limiter pole. Background Art

[0002] For electrical equipment operating at high voltages (eg 1500 V), high-rated (above 2000 A) DC electrical switches are used. This is particularly encountered in photovoltaic equipment.

[0003] The technology for reducing the arc using a magnetic circuit, an extinguishing chamber provided with an isolator, arc contacts and an arc angle, known for example from EP 3 232 457, enables the arc to be controlled to certain voltage and amperage levels. However, for the above applications, the known technology is not reliable enough or has insufficient current switching capability. Summary of the invention

[0004] The present invention aims to overcome these disadvantages by providing a novel limiter pole for an electrical switch which allows switching of high voltage and high amperage lines.

[0005] To this end, the invention relates to a limiter pole for a multi-pole DC electrical switch, comprising a compartment in which an input terminal and an output terminal for a direct current are arranged. According to the invention, the limiter pole comprises a first electrical contact connected to the input terminal and a second electrical contact connected to the output terminal, a third and a fourth electrical contact connected in series with each other, the third and the fourth contacts being able to move simultaneously relative to the first and the second electrical contacts between a closed position and an open position, in which the first and the third contacts and the second and the fourth contacts are in contact with each other to allow a direct current to flow between the input terminal and the output terminal, and in which the contacts are away from each other to interrupt the flow of current between the input terminal and the output terminal. The limiter pole comprises: a first arc formation chamber in which the first and the third electrical contacts are placed; a second arc formation chamber in which the second and the fourth electrical contacts are placed; and a first and a second arc extinction chamber, which are respectively associated with the first and the second arc formation chamber.

[0006] By means of the invention, a double switching pole is achieved, which makes it possible to form and isolate arcs formed at two different locations and process them independently. This makes it possible to significantly increase the amperage flowing through the pole, in particular for voltages up to 1500V.

[0007] According to an advantageous but non-mandatory aspect of the invention, such a limiter pole may combine one or more of the following features in any technically feasible combination:

[0008] - the first and second extinguishing chambers comprise partitions having projections pointing in the direction of the arc formation chamber and arranged on either side of a median plane of each extinguishing chamber;

[0009] - the third and fourth contacts are arranged on a first movable part actuated by a switching mechanism of the switch, and the first movable part comprises an electrical connection element between the third and fourth contacts;

[0010] - each of the first and second arc forming chambers comprises a magnetic circuit comprising a magnet and generating a magnetic field configured to direct an arc formed between contacts arranged in the arc forming chamber in the open position in the direction of an extinguishing chamber associated with the arc forming chamber;

[0011] - the first and second arc forming chambers are positioned side by side along the longitudinal axis of the switch;

[0012] - The third and fourth electrical contacts are each formed by a pair of fingers.

[0013] The invention also relates to a high voltage multi-pole DC electrical switch, comprising a molded housing, the molded housing comprising a body, the body being divided into a plurality of internal compartments, each internal compartment being associated with one pole of the switch, and a switching mechanism. One pole of the switch is formed by a limiter pole, whose compartment is formed by one of the internal compartments of the body and whose contacts are separated by the switching mechanism. The switch comprises at least one conducting pole, which is provided with an input terminal and an output terminal, a first series of electrical contacts connected to the input terminal and a second series of electrical contacts connected to the output terminal, the first and second series of electrical contacts being capable of being separated by the switching mechanism. The switching mechanism is configured to separate the contacts of one or more conducting poles before the contacts of the limiter pole.

[0014] According to an advantageous but non-mandatory aspect of the invention, such a switch may combine one or more of the following features in any technically feasible combination:

[0015] - the third and fourth contacts of the limiter pole are arranged on the first movable part, the second series of contacts of the conductive pole are arranged on the second movable part, and the switching mechanism comprises: an actuating shaft on which a rotating arm is arranged; a first connecting rod, which connects one of the rotating arms to the first movable part; and at least one second connecting rod, which connects one of the rotating arms to the second movable part, and the length of the first connecting rod is greater than the length of the second connecting rod;

[0016] - a second series of electrical contacts of the conducting electrode comprising at least 10 contacts, each contact being supported by a finger rigidly connected to a movable part of the conducting electrode, the part being actuated by a switching mechanism;

[0017] - The multi-pole switch comprises three conducting electrodes. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The invention will be better understood and its other advantages will become more apparent from the following description of a switch pole and a switch according to its principle, the description being provided by way of non-limiting example and with reference to the accompanying drawings, in which:

[0019] Figure 1 is a perspective view of a switch according to the present invention;

[0020] Figure 2 yes Figure 1 A longitudinal section of a switch;

[0021] Figure 3 is the limiter pole according to the present invention through Figure 2 A cross-sectional view of plane III-III in FIG.

[0022] Figure 4 is a switch according to the present invention. Figure 2 A cross-sectional view of plane IV-IV in FIG.

[0023] Figure 5 It is along Figure 4 The plane VV passes through Figure 1 A cross-sectional view of a switch;

[0024] Figure 6 yes Figure 5 A magnified view of the detail VI in;

[0025] Figure 7 It is intercepted by plane III-III Figure 1 A perspective view of a switch;

[0026] Figure 8 It is intercepted by plane IV-IV Figure 1 A perspective view of a switch;

[0027] Fig. 9 It is along Figure 2 The plane IX-IX in the Figure 1 A cross-sectional view of a conductive electrode of a switch;

[0028] Fig.10 It is along Figure 2 Cross-sectional view through the limiter pole in plane XX. DETAILED DESCRIPTION

[0029] The present invention relates to a DC switch with a high rating, for example above 2000 A. Such a switch is particularly used in 1500 V photovoltaic devices or power stations.

[0030] Figure 1A high voltage multi-pole DC electrical switch 2 is shown having a molded housing 4 comprising a body 6 divided into a plurality of internal compartments, in this example four compartments 6A, 6B, 6C and 6D, which are located side by side along a longitudinal axis X of the switch 2. The switch 2 comprises a plurality of poles A, B, C and D, and each compartment 6A, 6B, 6C and 6D is associated with one of the poles A, B, C and D of the switch 2.

[0031] The switch 2 also comprises a switching mechanism 8 which is triggered when the current has to be interrupted by mechanical, electrical, electronic or other means.

[0032] The switch 2 comprises a limiter pole formed by a pole B comprising a compartment formed by a compartment 6B of a body 6. In this compartment 6B there are arranged input terminals 10 for direct current and output terminals 12. These terminals 10 and 12 are connected to the power distribution network and the electrical equipment, respectively.

[0033] Limiter pole B comprises a first electrical contact 14 connected to input terminal 10 and a second electrical contact 16 connected to output terminal 12. Contacts 14 and 16 are formed by elongated members extending from terminals 10 and 12. Contacts 14 and 16 comprise contact pads 140 and 160 forming a planar surface and positioned side by side along axis X.

[0034] The limiter pole B also includes a third electrical contact 18 and a fourth electrical contact 20, which are connected in series with each other. These third and fourth contacts 18 and 20 are capable of being simultaneously moved between a closed position and an open position relative to the first and second electrical contacts 14 and 16, respectively. Fig.10 In the closed position shown, the first and third contacts 14 and 18 and the second and fourth contacts 16 and 20, respectively, are in contact with each other, thereby allowing direct current to flow between the terminals 10 and 12. Fig.10 In Figure 1, only the contact between contacts 14 and 18 is visible, contacts 16 and 20 are hidden. Figure 3 , 4 , 7 and 8, the contacts are spaced apart from each other, thereby interrupting the flow of current between the terminals 10 and 12. The contacts can be separated by a switching mechanism 8.

[0035] The third and fourth contacts 18 and 20 are arranged on a movable part 22 actuated by the switching mechanism 8. The movable part 22 is movable by rotation about a rotation axis X22 extending parallel to the longitudinal axis X.

[0036] Each of the contacts 18 and 20 is supported by a corresponding pair of fingers 24 and 26 rigidly connected to the mobile part 22. The contacts 18 and 20 are provided in the form of contact pads attached to the pair of fingers 24 and 26. The pair of fingers 24 and 26 can be moved by rotating relative to the mobile part 22 about the axis X24 and are urged in the direction of the contacts 14 and 16 by the spring 28, thereby maximizing the contact strength in the closed position.

[0037] The movable part 22 includes an electrical connection element between the third and fourth contacts 18 and 20, allowing them to be electrically connected in series. The contact element can be a pin 30 made of a conductive material, which is shared by the pair of fingers 24 and 26 and passes through the movable part 22, aligned with the axis X24 and allowing the pair of fingers 24 and 26 to rotate freely relative to the movable part 22 while being supported. Then, the contacts 18 and 20 are connected in series by the conduction of the pin 30.

[0038] As a variant, the connection can be made using conductive elements, such as conductive braided connectors 32 and 34 extending between the pairs of fingers 24 and 26 and conductive pins (not shown) supporting the movable part 22 rotating about the axis X22. In this case, the contacts 18 and 20 are connected in series through the conductive braided connectors 32 and 34 and the aligned conductive pins on the axis X22.

[0039] When the contacts are closed, the current Figure 7 and 8 As shown by arrow F1 in FIG. 1 , the wire flows from terminal 10 to contact 14 , then to contact 18 , then through pin 30 or braided connectors 32 and 34 to contact 20 , then to contact 16 , and finally to terminal 12 .

[0040] The limiter pole B comprises a first arc forming chamber 36 in which the first electrical contact 14 and the third electrical contact 18 are placed. The limiter pole B comprises a second arc forming chamber 38 in which the second electrical contact 16 and the fourth electrical contact 20 are placed. The chambers 36 and 38 are where the arc generated when the contacts are opened is formed. The chambers 36 and 38 are separated in the direction of the axis X by a central wall 60 of the body 6, which extends perpendicularly to the axis X to the center of the compartment 6B.

[0041] In order to extinguish the arc generated by the separation of the contacts, the limiter pole B also includes a first extinguishing chamber 40 and a second extinguishing chamber 42, which are respectively associated with the first arc forming chamber 36 and the second arc forming chamber 38. The extinguishing chamber 40 is connected to the chamber 36, and the two chambers 36 and 40 form a single space, which is delimited along the axis X by the central wall 60 and the wall 62 of the body 6, which separates the compartment 6B from the compartment 6C. On the other side of the central wall 60, the extinguishing chamber 42 is connected to the chamber 38, and the two chambers 38 and 42 form a single space, which is delimited along the axis X by the central wall 60 and the wall 64 of the body 6, which separates the compartment 6B from the compartment 6A. The first and second arc forming chambers 36 and 38 are positioned side by side along the axis X.

[0042] Each of the first and second extinguishing chambers 40 and 42 comprises a partition 44 formed by parallel metal plates stacked on a plane extending parallel to the axis X. These partitions 44, of which there may be 30, are stacked in the height direction relative to the compartment 6B between the bottom 66 and the upper wall 68, in the vicinity of which the terminal 66 is located. The partition 44 has a central recess 440 which delimits two portions situated on either side of a median plane P44 perpendicular to the axis X, which is also the median plane of each extinguishing chamber 40 and 42. Advantageously, each partition 44 has a protrusion 442 which points in the direction of the arc formation chambers 36 and 38 and partially extends into these chambers, and which is arranged on either side of the median plane P44 of each extinguishing chamber 40 and 42. These protrusions make it possible to capture arcs of low amperage, in particular between 10A and 100A, as in the case of arcs of high amperage (above 100A, up to 40,000A), they are not guided by electromagnetic forces in the axial direction of the extinguishing chambers 40 and 42 .

[0043] Each extinguishing chamber 40 and 42 comprises an arc contact 46 which extends between the partition 44 at the top of the stack and the upper wall 68 and is directed obliquely towards the associated arc formation chamber 36 or 38. The purpose of these arc contacts is to direct the arc towards the partition 44.

[0044] Each quenching chamber 40 and 42 also includes an arc horn 48 extending at the bottom of the stack between the bottom 46 and the partition 44 and directed toward the corresponding contact 14 or 16 located in the forming chamber 36 or 38 associated with the quenching chamber 40 or 42. The purpose of the arc horn 48 is also to direct the arc toward the partition 44.

[0045] Each of the first and second arc forming chambers 36 and 38 includes a magnetic circuit including a magnet and generating a magnetic field configured to guide an arc formed between contacts disposed in the arc forming chamber 36 or 38 in the open position in the direction of the extinguishing chamber 40 or 42 associated with the arc forming chamber 36 or 38. More specifically, the arc forming chamber 36 includes a magnetic circuit 50 including a magnet 500 located below the contact 14, and a rod 502 made of a magnetic material in a "U" shape, also located below the contact 14 and in close proximity to the magnet 500, and having arms extending into the chamber 36 on either side of the pair of fingers 24. The magnetic field generated by the magnet 500 and directed by the rod 502 attracts a low amperage arc toward the extinguishing chamber 40.

[0046] Similarly, the forming chamber 38 includes a magnetic circuit 52, which includes a magnet 520, which is located below the contact 16, and a rod 522 made of magnetic material in a "U" shape, which is also located below the contact 16 and adjacent to the magnet 520, and whose arms extend into the chamber 38 on either side of the pair of fingers 26. The magnetic field generated by the magnet 520 and guided by the rod 522 attracts the low amperage arc toward the extinguishing chamber 42.

[0047] The structure of the limiter pole B allows switching of the current at two points in series, which enables the arc associated with the interruption current to be divided and processed separately in two different extinguishing chambers. As a result, the voltages that can be switched are much higher than with conventional limiter poles with only one extinguishing chamber. In the present case, the two "arc formation chamber / extinguishing chamber" pairs of the limiter pole B make it possible to switch up to, for example, 750 V per pair, for a total of 1500 V, in particular for photovoltaic plants generating such voltages.

[0048] The switch 2 also includes at least one conductive electrode. In this example, the switch 2 includes three conductive electrodes formed by electrodes A, C and D. Since the conductive electrodes C and D are structurally identical to the conductive electrode A, only the conductive electrode A will be described below.

[0049] Conductive electrode A is provided with an input terminal 54 and an output terminal 56. Conductive electrodes C and D also each include an input terminal 54. Figure 2 As shown, the input terminals 54 of the conductive electrodes A, C and D and the input terminal 10 of the limiter electrode B are connected to each other through an equipotential rod 76. The equipotential rod 76 is a member made of a conductive material, which is inserted into holes in the three input terminals 54 and the input terminal 10 and prevents potential differences between these members.

[0050] Conductor A also includes a first series of electrical contacts 58 connected to input terminal 54 and a second series of electrical contacts 70 connected to output terminal 56. The first and second series of electrical contacts 58 and 70 can be separated by switching mechanism 8, such as Fig. 9shown with the contacts in an open configuration.

[0051] The switching mechanism 8 is configured to separate the contacts of the conducting poles A, C and D before the contacts of the limiter pole B. The poles A, B, C and D are connected in a parallel arrangement. The desired goal is to concentrate the arcing effect in the limiter pole B.

[0052] The second series of electrical contacts 70 of the conducting electrode A comprises at least ten contacts, each supported by a finger 72 rigidly connected to a mobile part 74 actuated by the switching mechanism 8. The mobile part 74 is movable by rotation about an axis X74 extending parallel to the axis X. With the contacts 58 and 70 in the closed configuration, the current flows through the contact 70 towards the output terminal 56 via the finger 72 and the mobile part 74.

[0053] The switching mechanism 8 includes an actuating shaft 80 on which a rotating arm 82 is provided, each of which is associated with one of the poles A, B, C and D, and whose function is to actuate the disconnection of the contacts of the pole. The rotation of the actuating shaft 80 causes the simultaneous rotation of the rotating arms 82. The rotating arms 82 are connected to the movable parts 22 and 74 via a connecting rod. The switching mechanism 8 includes: a first connecting rod 84, which connects one of the rotating arms 82 to the first movable part 22; and at least one second connecting rod 86, which connects the other rotating arm 82 to the second movable part 74. In order to disconnect the conductive electrode A before the limiter pole B, the length L2 of the first connecting rod 84 is greater than the length L1 of the second connecting rod 86. This allows for a time ( L2 ) immediately after the contact of the conductive electrode A is disconnected. Fig. 9 ), for the same rotation angle of the shaft 80, the contacts of the limiter pole B remain against each other ( Fig.10 ).

[0054] What is thus obtained is an offset between the openings which can be adjusted to, for example, 5° using mechanical means, ie without the intervention of electronic controls or other accessories. The reliability of the switch 2 is thus improved.

[0055] Figure 2 The switch 2 shown in is a single-pole disconnector, rated for example for 10000 A (through three conducting poles A, C and D with 10 fingers in parallel), which can switch for example 20 kA at a voltage of 1500 V (using limiter pole B).

[0056] According to an embodiment not shown, the switch 2 may comprise a plurality of conducting electrodes other than three, in particular one or two conducting electrodes.

Claims

1. A high voltage multi-pole DC electrical switch (2) comprising a molded housing (4) and a switching mechanism (8), the molded housing comprising a body (6) divided into a plurality of internal compartments (6A, 6B, 6C, 6D), each internal compartment being associated with one pole (A, B, C, D) of the switch (2), characterized in that One pole of the switch (2) is formed by a limiter pole (B), which comprises a compartment (6B) in which an input terminal (10) and an output terminal (12) for direct current are arranged, characterized in that it comprises a first electrical contact (14) connected to the input terminal (10) and a second electrical contact (16) connected to the output terminal (12), a third electrical contact (18) and a fourth electrical contact (20) connected in series with each other, the third electrical contact and the fourth electrical contact being able to move simultaneously between a closed position and an open position relative to the first electrical contact and the second electrical contact, respectively, in which the first electrical contact (14) and the third electrical contact (18) as well as the second electrical contact (16) and The fourth electrical contacts (20) are in contact with each other to allow direct current to flow between the input terminal (10) and the output terminal (12), and in the disconnected position, the electrical contacts are away from each other to interrupt the flow of current between the input terminal (10) and the output terminal (12), and the limiter pole (B) includes: a first arc forming chamber (36) in which the first electrical contact (14) and the third electrical contact (18) are placed; a second arc forming chamber (38) in which the second electrical contact (16) and the fourth electrical contact (20) are placed; and a first arc extinguishing chamber (40) and a second arc extinguishing chamber (42), which are respectively associated with the first arc forming chamber (36) and the second arc forming chamber (38), The compartment (6B) is formed by one of the internal compartments (6A, 6B, 6C, 6D) of the body (6) and its electrical contacts (14, 18, 16, 20) are separated by a switching mechanism (8), the switch comprising at least one conductive pole (A, C, D) provided with an input terminal (54) and an output terminal (56), a first series of electrical contacts (58) connected to the input terminal (54) and a second series of electrical contacts (70) connected to the output terminal (56), the first series of electrical contacts and the second series of electrical contacts being separable by the switching mechanism, and the switching mechanism (8) being configured to separate the first series of electrical contacts and the second series of electrical contacts of one or more conductive poles (A, C, D) before the electrical contacts (14, 18, 16, 20) of the limiter pole (B).

2. The high voltage multi-pole DC electrical switch according to claim 1, characterized in that: The first and second quenching chambers (40, 42) include a partition (44) having a protrusion (442) pointing in the direction of the arc formation chamber (36, 38) and arranged on both sides of a middle plane (P44) of each quenching chamber (40, 42).

3. The high voltage multi-pole DC electrical switch according to claim 1, characterized in that: The third electrical contact (18) and the fourth electrical contact (20) are arranged on a first movable part (22) actuated by a switching mechanism (8) of the switch (2), and the first movable part (22) comprises an electrical connection element (30; 32, 34) between the third electrical contact (18) and the fourth electrical contact (20).

4. A high voltage multi-pole DC electrical switch according to any one of the preceding claims, characterised in that Each of the first arc forming chamber (36) and the second arc forming chamber (38) comprises a magnetic circuit (50, 52) comprising a magnet (500, 520) and generating a magnetic field configured to guide an arc formed between electrical contacts (14, 18, 16, 20) arranged in the arc forming chamber (36, 38) in an open position in the direction of an extinguishing chamber (40, 42) associated with the arc forming chamber (36, 38).

5. A high voltage multi-pole DC electrical switch according to any one of claims 1 to 3, characterized in that: The first and second arc forming chambers (36, 38) are positioned side by side along a longitudinal axis (X) of the switch (2).

6. A high voltage multi-pole DC electrical switch according to any one of claims 1 to 3, characterized in that: The third electrical contact (18) and the fourth electrical contact (20) are each formed by a pair of fingers (24, 26).

7. The high voltage multi-pole DC electrical switch according to claim 1, characterized in that: The third electrical contact (18) and the fourth electrical contact (20) of the limiter pole (B) are arranged on the first movable part (22), and the second series of electrical contacts (70) of the conductive poles (A, C, D) are arranged on the second movable part (74). The switching mechanism (8) comprises: an actuating shaft (80) on which a rotating arm (82) is arranged; a first connecting rod (84) which connects one of the rotating arms (82) to the first movable part (22); and at least one second connecting rod (86) which connects one of the rotating arms (82) to the second movable part (74), and the length of the first connecting rod (84) is greater than the length of the second connecting rod (86).

8. The high voltage multi-pole DC electrical switch according to claim 1, characterized in that: The second series of electrical contacts (70) of the conducting poles (A, C, D) comprises at least 10 electrical contacts, each electrical contact being supported by a finger (72) rigidly connected to a movable part (74) of the conducting poles (A, C, D) actuated by a switching mechanism (8).

9. A high voltage multi-pole DC electrical switch according to any one of claims 1 to 3, characterized in that: It consists of three conductive electrodes (A, C, D).

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