RU2804272C2 - Limiting pole for electric switch and dc switch including such limiting pole - Google Patents

Abstract

FIELD: electrical equipment.

SUBSTANCE: limiting pole of an electrical switch and a multi-pole electrical switch. Limiting pole (B) is provided for DC multi-pole electrical switch (2), which includes main body (6) consisting of several internal compartments (6A, 6B, 6C, 6D), each associated with one pole (A, B, C, D) of switch (2), and switching mechanism (8), while limiting pole (B) contains a compartment in which an input terminal and an output terminal for direct electrical current are provided, along with the first electrical contact connected to the input terminal, and connected to the output terminal by the second electrical contact, the third and fourth electrical contacts connected in series with each other, and the third and the fourth contacts can move simultaneously with respect to the first and the second electrical contacts, respectively, between the closed position, in in which the first and the third contacts and the second and the fourth contacts are in contact with each other, allowing the flow of direct current between the input terminal and the output terminal, and the open position, in which the said contacts are located at a distance from each other, interrupting the flow of current between the input terminal lead and output terminal lead. Limiting pole (B) contains the first arc formation chamber, in which the first and the third electrical contacts are placed, the second electric arc formation chamber, in which the second and the fourth electrical contacts are placed, and the first and the second chambers for extinguishing the electric arc, which are connected with the first and the second chambers to form an electric arc, respectively.

EFFECT: improvement in reliability of the circuit breaker by providing reliable arc extinguishing.

10 cl, 10 dwg

Description

The present invention relates to a limiting pole for an electric switch and to a DC electric switch including such a limiting pole.

For electrical installations operating at high voltages, such as 1500 V, DC electrical switches with high ratings (above 2000 A) are used. This situation occurs in particular in photovoltaic installations.

Arc extinguishing technologies using magnetic circuits, arc chutes equipped with spacers, arcing contacts and arcing horns, which are known, for example, from EP 322457, make it possible to control electric arcs up to certain voltage and current levels. However, for the applications mentioned above, the known technologies are not reliable enough or do not have sufficient current switching capabilities.

The invention aims to overcome these disadvantages by providing a new limiting pole for an electrical switch capable of switching high voltage and high current lines.

In this regard, the invention relates to a limiting pole for a multi-pole DC electric switch comprising a compartment in which an input terminal and an output terminal for direct electric current are provided. According to the invention, this limiting pole comprises a first electrical contact connected to the input terminal and a second electrical contact connected to the output terminal, third and fourth electrical contacts connected to each other in series, and the third and fourth contacts can be moved simultaneously relative to the first and fourth terminals. of the second electrical contacts, respectively, between a closed position in which the first and third contacts and the second and fourth contacts contact each other, allowing a constant electric current to flow between the input terminal and the output terminal, and an open position in which said contacts are located on away from each other, interrupting the flow of current between the input terminal and the output terminal. The limiting pole comprises a first arc-forming chamber in which first and third electrical contacts are located, a second arc-forming chamber in which the second and fourth electrical contacts are located, and first and second arc-extinguishing chambers that are connected to the first and second chambers. formation of an electric arc, respectively.

Thanks to the invention, a double switching pole is provided which makes it possible to form and isolate electric arcs that occur in two different places and to extinguish them in an independent manner. This makes it possible to significantly increase the current flowing through the pole, in particular for voltages up to 1500 V.

According to advantageous, but not essential, aspects of the invention, such a limiting pole may include one or more of the following features in any technically feasible combination:

- the first and second arc-extinguishing chambers contain separators having protrusions that are directed towards the chambers for forming the electric arc and are located on both sides of the symmetry plane of each arc-extinguishing chamber;

- the third and fourth contacts are provided on the first movable part, which is driven by the switching mechanism of the switch, and the first movable part includes an electrical connecting element between the third and fourth contacts;

- each of the first and second arc-forming chambers contains a magnetic circuit that includes a magnet and creates a magnetic field that is configured to direct, in the direction of the arc-extinguishing chamber associated with this arc-forming chamber, the formation of an electric arc in an open position between contacts that are provided in this arc formation chamber;

- the first and second arc formation chambers are located side by side along the longitudinal axis of the switch;

- the third and fourth electrical contacts are each formed separately by one pair of fingers.

The present invention also relates to a high voltage multi-pole DC electrical switch including a molded housing including a main body that is divided into a plurality of internal compartments each associated with one pole of the switch, and a switching mechanism. One of the poles of the switch is formed by a limiting pole, the compartment of which is formed by one of the internal compartments of the main body, the contacts of which can be separated by a switching mechanism. The switch includes at least one conductive pole provided with an input contact terminal and an output terminal terminal, with a first row of electrical contacts that are connected to the input terminal terminal, and with a second row of electrical contacts that are connected to the output terminal terminal, the first and second rows electrical contacts can be separated by a switching mechanism. The switching mechanism is configured to separate the contacts of one or more conductive poles before the contacts of the limiting pole.

According to advantageous, but not essential, aspects of the invention, such a switch may include one or more of the following features in any technically feasible combination:

- the third and fourth contacts of the limiting pole are made on the first movable part, the second row of contacts of the conductive pole are made on the second movable part, the switching mechanism includes: a drive shaft on which the rotary levers are made, a first connecting rod connecting one of the rotary levers to the first a movable part, and at least one second connecting rod connecting one of the rotary arms to the second movable part, and the length of the first connecting rod is greater than the length of the second connecting rod;

- the second row of electrical contacts of the conductive pole includes at least 10 contacts, each of which rests on one finger, which is rigidly connected to a movable part of this conductive pole, this part being driven by a switching mechanism;

- This multi-pole switch includes three conductive poles.

The present invention will be better understood and its other advantages will become more apparent in the light of the following description of the poles for the switch and switch, which are presented in accordance with the principles of the present invention, set forth by non-limiting example and with reference to the accompanying drawings, in which:

fig. 1 is a perspective view of a switch according to the invention;

fig. 2 - longitudinal section of the switch (Fig. 1);

fig. 3 is a section along plane III-III (Fig. 2) of the limiting pole according to the invention;

fig. 4 is a section along the plane IV-IV (Fig. 2) of a pole for a switch according to the invention;

fig. 5 - section of the switch (Fig. 1) along the plane VV (Fig. 4);

fig. 6 is an enlarged view of detail VI (Fig. 5);

fig. 7 is a perspective view of the switch (Fig. 1) in section along plane III-III;

fig. 8 is a perspective view of the switch (Fig. 1) in section along plane IV-IV;

fig. 9 - section of the conductive pole for the switch (Fig. 1) along the IX-IX plane (Fig. 2);

fig. 10 - section of the limiting pole along plane XX (Fig. 2).

The present invention relates to high rated DC circuit breakers, for example higher than 2000 A. Such a circuit breaker can be used in particular in photovoltaic installations or 1500 V farms.

In fig. 1 shows a high voltage multi-pole DC electrical switch 2 having a molded body 4 including a main body 6 which is divided into a plurality of internal compartments, in this example four compartments 6A, 6B, 6C and 6D, which are arranged side by side along longitudinal axis X of the switch 2. The switch 2 includes a plurality of poles A, B, C and D, and each of the compartments 6A, 6B, 6C and 6D is connected to one of the poles A, B, C and D of the switch 2.

The switch 2 also includes a switching mechanism 8 that is actuated when the flow of current is interrupted by mechanical, electrical, electronic or other means.

The switch 2 includes a limit pole formed by pole B, which contains a compartment formed by a chamber 6V of the main body 6. In this compartment 6V, an input terminal 10 and an output terminal 12 for direct electric current are provided. These terminals 10 and 12 are connected to the electrical distribution network and to the electrical device, respectively.

The limiting pole B includes a first electrical contact 14, which is connected to the input terminal 10, and a second electrical contact 16, which is connected to the output terminal 12. Contacts 14 and 16 are formed by elongated portions that extend from terminals 10 and 12. Contacts 14 and 16 include pads 140 and 160 that form planar surfaces and are located side by side along the X-axis.

The limiting 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 can simultaneously move relative to the first and second electrical contacts 14 and 16, respectively, between a closed position and an open position. In the closed position shown in FIG. 10, the first and third contacts 14 and 18 and the second and fourth contacts 16 and 20 are in contact with each other, respectively, so that a constant electric current can flow between the contact terminals 10 and 12. In FIG. 10 only the contact between pins 14 and 18 is visible, while pins 16 and 20 are not visible. In the open position shown in FIG. 3, 4, 7 and 8, the contacts are located at a distance from each other, interrupting the flow of current between the contact terminals 10 and 12. The contacts can be separated by a switching mechanism 8.

The third and fourth contacts 18 and 20 are provided on the movable part 22, which is driven by the switching mechanism 8. The movable part 22 can be moved by rotation about a rotation axis X22, which runs parallel to the longitudinal axis X.

Each of the contacts 18 and 20 is supported by one corresponding pair of fingers 24 and 26, which are rigidly attached to the movable part 22. These contacts 18 and 20 are made in the form of contact pads, which are attached to the pairs of fingers 24 and 26. The pairs of fingers 24 and 26 can rotate relative to the moving part 22 around the X24 axis and move by springs 28 in the direction of contacts 14 and 16 in order to maximize the contact force in the closed position.

The movable part 22 includes an electrical connecting element between the third and fourth contacts 18 and 20, providing them with a series electrical connection. This contact element may be a pin 30 made of a conductive material common to pairs of fingers 24 and 26 and extending through the movable part 22, aligned with the X24 axis and allowing the pairs of fingers 24 and 26 to be supported while remaining free to rotate relative to the movable part 22. Pins 18 and 20 are then connected in series by electrical conduction through pin 30.

Alternatively, the connection may be made using conductive members, such as conductive braided connectors 32 and 34 extending between pairs of pins 24 and 26 and a conductive pin (not shown) supporting the movable portion 22 as it rotates about axis X22. In such a case, pins 18 and 20 are connected in series through conductive braided connectors 32 and 34 and an aligned conductive pin on axis X22.

When the contacts are closed, current flows as shown by arrows F1 in FIG. 7 and 8, from pin 10 to pin 14, then to pin 18, then to pin 20 via pin 30 or braided connectors 32 and 34, then to pin 16 and finally to pin 12.

The limiting pole B includes a first arcing chamber 36, which houses a first electrical contact 14 and a third electrical contact 18. The limiting pole B includes a second arcing chamber 38, which houses a second electrical contact 16 and a fourth electrical contact 20. In the chambers 36 and 38 of the formation of an electric arc, electric arcs are formed that occur when the contacts open. The arc forming chambers 36 and 38 are separated in the X-axis direction by a central wall 60 of the main body 6, which extends perpendicular to the X-axis at the center of the compartment 6B.

For extinguishing electric arcs resulting from separation of the contacts, the limiting pole B also includes a first arc chute 40 and a second arc chute 42, which are connected to the first arc forming chamber 36 and the second arc forming chamber 38, respectively. The arcing chamber 40 is adjacent to the arc forming chamber 36, and these two chambers 36 and 40 form a single space limited along the X-axis by the central wall 60 and the wall 62 of the main body 6, which separates the compartment 6B from the compartment 6C. On the other side of the central wall 60, the arc-extinguishing chamber 42 is adjacent to the arc-forming chamber 38, and the two chambers 38 and 42 form a single space defined along the X-axis by the central wall 60 and the wall 64 of the main body 6, which separates compartment 6B from compartment 6A. The first and second arc-forming chambers 36 and 38 are arranged side by side along the X-axis.

Each of the first and second arc chutes 40 and 42 includes spacers 44 formed by parallel metal plates that are stacked in planes running parallel to the X-axis. These spacers 44, of which there may be 30, are stacked in height relative to the compartment 6B between the bottom 66 , near which the contact terminal 10 is located, and the top wall 68. The separators 44 have central recesses 440 that separate two sections that are located on either side of the plane of symmetry P44, perpendicular to the X-axis, which is also the plane of symmetry of each of the arc chutes 40 and 42. Advantageously, each separator 44 has protrusions 442 that are directed toward, partially protrude into, and partially protrude into the arc forming chambers 36 and 38, and are located on either side of the symmetry planes P44 of each of the arc extinguishing chambers 40 and 42. These protrusions allow the arcing chambers 40 and 42 to be captured. low current arcs, in particular between 10 A and 100 A, which are not driven in the direction of the axis of the arc chambers 40 and 42 by electromagnetic force, as in the case of high current electric arcs (above 100 A, up to 40,000 A).

Each of the arc chambers 40 and 42 includes an arc contact 46 that extends between the top of the stack separator 44 and the top wall 68 and is directed obliquely into an associated arc forming chamber 36 or 38. The purpose of these arcing contacts is to direct electric arcs towards the separators 44.

Each of the arc chambers 40 and 42 also includes an arc horn 48 that extends between the bottom 46 and the bottom of the foot separator 44 and is directed toward a corresponding contact 14 or 16 located in the arc forming chamber 36 or 38 associated with arc-extinguishing chamber 40 or 42. The purpose of the arc-extinguishing horns 48 is also to direct electric arcs towards the separators 44.

Each of the first and second arc-forming chambers 36 and 38 includes a magnetic circuit that includes a magnet and creates a magnetic field that is designed to be directed toward an arc-extinguishing chamber 40 or 42 associated with the arc-forming chamber 36 or 38 electric arc, an electric arc formed in an open position between the contacts that are provided in this arc-forming chamber 36 or 38. More specifically, the arc chamber 36 includes a magnetic circuit 50 including a magnet 500 that is located below the contact 14 and a plate 502 made of magnetic material in the shape of a "U" that is also located below the contact 14 and opposite the magnet 500 , and the arms of which continue into the arc forming chamber 36 on either side of the pair of fingers 24. The magnetic field created by the magnet 500 and directed by the plate 502 attracts low current arcs to the arc chamber 40.

Likewise, the arc chamber 38 includes a magnetic circuit 52 including a magnet 520, which is located under the contact 16, and a plate 522 made of magnetic material in the shape of the letter "U", which is also located under the contact 16 and opposite the magnet 520 , the arms of which continue into the arc forming chamber 38 on either side of the pair of fingers 26. The magnetic field created by the magnet 520 and directed by the plate 522 attracts low current arcs to the arc chamber 42.

The design of the limiting pole B provides current switching at two consecutive points, allowing arcs associated with current interruption to be separated and extinguished separately in two different arc chutes. As a result, it is possible to achieve switching voltages with a higher value than traditional limiting poles having only one arc chute. In this case, two arcing chamber/arcing chamber pairs of limiting pole B provide switching of, for example, up to 750 V per pair, giving a total of 1500 V, in particular for photovoltaic farms that generate such a voltage.

The switch 2 further includes at least one conductive pole. In this example, the switch 2 includes three conductive poles formed by poles A, C and D. Only conductive pole A will be described below since conductive poles C and D are identical in design to conductive pole A.

The conductive pole A is provided with an input terminal 54 and an output terminal 56. Each of the conductive poles C and D also includes an input terminal 54. As can be seen in FIG. 2, the input terminals 54 of the conductive poles A, C and D and the input terminal 10 of the limiting pole B are connected to each other by an equipotential bus 76. This equipotential bus 76 is an element made of a conductive material, which is inserted into the holes in the three input terminals terminals 54 and at the input terminal 10 and prevents differences in electrical potential from occurring between these elements.

The conductive pole A also includes a first row of electrical contacts 58, which are connected to the input terminal 54, and a second row of electrical contacts 70, which are connected to the output terminal 56. The first and second rows of electrical contacts 58 and 70 can be separated by a switching mechanism 8, as shown in Fig. 9, with contacts in open configuration.

The switching mechanism 8 is configured to separate the contacts of the conductive poles A, C and D before the contacts of the limiting pole B. The poles A, B, C and D are connected in a parallel arrangement. The desired goal is for the effects of the electric arc to be concentrated at the limiting pole.

The second row of electrical contacts 70 of conductive pole A includes at least 10 contacts, each of which is supported by a finger 72, which is rigidly connected to a movable part 74 driven by the switching mechanism 8. The movable part 74 is movable when rotating about an axis X74 , which runs parallel to the X-axis. When contacts 58 and 70 are positioned in a closed configuration, current flows through contacts 70 to output terminal 56 through pins 72 and moving part 74.

The switching mechanism 8 includes a drive shaft 80 on which are provided rotary arms 82, each of these rotary arms 82 associated with one of the poles A, B, C and D, and the purpose of which is to open the contacts of that pole. Rotation of the drive shaft 80 causes simultaneous rotation of the swing arms 82. The swing arms 82 are connected to the moving parts 22 and 74 using connecting rods. The switching mechanism 8 includes a first connecting rod 84 connecting one of the swing arms 82 to the first movable part 22, and at least one second connecting rod 86 connecting the other swing arm 82 to the second moving part 74. In order to open the conductive pole A before the limiting pole B, the length L2 of the first connecting rod 84 must be greater than the length L1 of the second connecting rod 86. This makes it possible to ensure that during the period of time immediately following the opening of the contacts of the conductive pole A (Fig. 9) with one and At the same angle of rotation of the shaft 80, the contacts of the limiting pole B remained pressed against each other (Fig. 10).

In this way, an offset between the holes is obtained, which can be, for example, 5°, using mechanical means, that is, without the use of electronic controls or other devices. Thus, the reliability of switch 2 is increased.

Switch 2 shown in FIG. 2 is a single-pole switch-disconnector, for example, with a current rating of 10000 A (due to three conducting poles A, C and D with 10 fingers arranged in parallel), which can provide switching, for example, at a current of 20 kA and a voltage of 1500 V (when using limit pole B).

According to an embodiment, which is not shown, the switch 2 may comprise several conductive poles other than three, in particular one or two conductive poles.

Claims (10)

1. A limiting pole (B) for a multi-pole DC electric switch (2), comprising a compartment (6B) in which an input terminal (10) and an output terminal (12) for direct electric current are provided, characterized in that it contains the first electrical contact (14) connected to the input terminal (10), and the second electrical contact (16) connected to the output terminal (12), the third (18) and fourth (20) electrical contacts connected to each other in series , wherein the third and fourth contacts (18, 20) are capable of moving simultaneously relative to the first and second electrical contacts (14, 16), respectively, between a closed position in which the first (14) and third (18) contacts and the second (16) and the fourth (20) contacts contact each other to allow a constant electric current to flow between the input terminal (10) and the output terminal (12), and an open position in which said contacts are spaced apart from each other, interrupting the flow current between the input contact terminal (10) and the output contact terminal (12), and the fact that the limiting pole (B) contains a first arc-forming chamber in which the first (14) and third (18) electrical contacts are located, the second chamber ( 38) forming an electric arc, in which the second (16) and fourth (20) electrical contacts are located, and the first (40) and second (42) electric arc extinguishing chambers, which are connected to the first (36) and second (38) formation chambers electric arc, respectively. 2. The limiting pole according to claim 1, characterized in that said first and second arc-extinguishing chambers (40, 42) contain separators (44) having projections (442) that are directed in the direction of the arc-forming chambers (36, 38) and provided on either side of the plane of symmetry (P44) of each said arc chute (40, 42). 3. A limiting pole according to any of the previous paragraphs, characterized in that the third (18) and fourth (20) contacts are provided on the first movable part (22), which is driven by the switching mechanism (8) of the switch (2), and in that that the first movable part (22) contains an electrical connecting element (30; 32, 34) between the third (18) and fourth (20) contacts. 4. The limiting pole according to one of the previous paragraphs, characterized in that each of the first (36) and second (38) arc-forming chambers contains a magnetic circuit (50, 52), which includes a magnet (500, 520) and generates a magnetic field which is intended to direct, in the direction of said arc-extinguishing chamber (40, 42) connected to this arc-forming chamber (36, 38), the electric arc formed in the open position between the contacts (14, 18, 16, 20), which are provided in this chamber (36, 38) for forming an electric arc. 5. Limiting pole according to one of the previous paragraphs, characterized in that the first and second chambers (36, 38) of electric arc formation are located side by side along the longitudinal axis (X) of the switch (2). 6. Limiting pole according to one of the previous paragraphs, characterized in that every third (18) and fourth (20) electrical contacts are formed by one pair of fingers (24, 26). 7. A high voltage multi-pole DC electrical switch (2) including a molded housing (4) including a main body (6) which is divided into several internal compartments (6A, 6B, 6C, 6D), each of which is connected with one pole (A, B, C, D) of the switch (2), and a switching mechanism (8), characterized in that one of the poles of the switch (2) is formed by the limiting pole (B) according to one of the previous paragraphs, compartment (6B ) which is formed by one of the internal compartments (6A, 6B, 6C, 6D) of the main body (6), and the contacts (14, 18, 16, 20) of which can be separated by a switching mechanism (8), in that the switch contains at least at least one conductive pole (A, C, D) provided with an input terminal (54) and an output terminal (56), with a first row of electrical contacts (58) which are connected to the input terminal (54), and a second row electrical contacts (70) that are connected to the output terminal (56), wherein the first and second rows of electrical contacts (58, 70) are designed to be separable by the switching mechanism, and in that the switching mechanism (8) is designed to be separable by the contacts ( 58, 70) of one or more conductive poles (A, C, D) in front of the contacts (14, 18, 16, 20) of the limiting pole (B). 8. The switch according to claim 7, characterized in that the third (18) and fourth (20) contacts of the limiting pole (B) are provided on the first movable part (22), in that the second row of contacts (70) of the conducting pole (A, C, D) is provided on the second movable part (74), in that the switching mechanism (8) includes: a drive shaft (80) on which swing arms (82) are provided, a first connecting rod (84) connecting one of swing arms (82) with a first movable part (22), and at least one second connecting rod (86) connecting one of the swing arms (82) with a second movable part (74), and such that the length (L2) of the first the connecting rod (84) is longer than the length (L1) of the second connecting rod (86). 9. A switch according to any one of claims 7 and 8, characterized in that the second row of electrical contacts (70) of the conductive pole (A, C, D) includes at least 10 contacts, each of which rests on one finger (72 ) which is rigidly connected to the movable part (74) of this conductive pole (A, C, D), this part being driven by the switching mechanism (8). 10. Multi-pole switch according to one of claims 7-9, characterized in that it contains three conductive poles (A, C, D).