Zero-sequence mutual inductance structure and circuit breaker

Abstract

The invention provides a zero-sequence mutual inductance structure and a circuit breaker, and relates to the technical field of leakage protection. The zero-sequence mutual inductance structure comprises a current transformer and a phase line group; the current transformer comprises a housing and a magnetic ring, the housing is provided with an interphase separator, the interphase separator is provided with a first channel, a second channel and a third channel, and the magnetic ring is arranged around the interphase separator; the phase line group comprises an A-phase wiring board, an A-phase contact, a B-phase contact, a C-phase wiring board and a C-phase contact, the A-phase wiring board or the A-phase contact is arranged in the first channel in a penetrating manner, the A-phase wiring board is connected with the A-phase contact, the B-phase contact is arranged in the second channel in a penetrating manner, the C-phase wiring board or the C-phase contact is arranged in the third channel in a penetrating manner, and the C-phase wiring board is connected with the C-phase contact. According to the zero-sequence mutual inductance structure, the phase-to-phase separators are arranged on the housing to separate the phase lines, the creepage distance is longer, the insulation performance is better, the insulation requirement under the working conditions of high voltage and large current can be met, and potential safety hazards are eliminated.

Description

Technical Field

[0001] The invention relates to the technical field of leakage protection, and in particular to a zero-sequence mutual inductance structure and a circuit breaker. Background Art

[0002] When the phase sum of the three-phase current is not equal to zero, the current generated is the zero-sequence current, that is, the leakage current. In order to detect the zero-sequence current, a common practice is to connect a current transformer in the three-phase circuit, pass the phase line through the magnetic ring of the current transformer, and then detect whether there is an induced current in the secondary coil of the current transformer.

[0003] However, the three phase wires are very close when passing through the magnetic ring, and the insulation between the phases is poor. Although the phases can be isolated by wrapping insulating tape on the phase wires or adding insulating plugs between the phase wires, the phases may still be conductive under high voltage and high current conditions, posing a safety hazard. Summary of the invention

[0004] In order to solve the problems existing in the prior art, one of the objectives of the present invention is to provide a zero-sequence mutual inductance structure.

[0005] The present invention provides the following technical solutions: A zero-sequence mutual inductance structure includes a current transformer and a phase line group; The current transformer comprises a housing and a magnetic ring, the housing is provided with an interphase isolating member, the interphase isolating member is provided with a first channel, a second channel and a third channel, and the magnetic ring is provided around the interphase isolating member; The phase line group includes an A-phase terminal block, an A-phase contact, a B-phase contact, a C-phase terminal block and a C-phase contact. The A-phase terminal block or the A-phase contact is passed through the first channel, the A-phase terminal block is connected to the A-phase contact, the B-phase contact is passed through the second channel, the C-phase terminal block or the C-phase contact is passed through the third channel, and the C-phase terminal block is connected to the C-phase contact.

[0006] As a further optional solution to the zero-sequence mutual inductance structure, the A-phase wiring board or the A-phase contact includes a first connecting portion, the A-phase wiring board is connected to the A-phase contact through the first connecting portion, and the first connecting portion is located in the first channel; The C-phase wiring board or the C-phase contact includes a second connection portion, the C-phase wiring board and the C-phase contact are connected via the second connection portion, and the second connection portion is located in the third channel.

[0007] As a further optional solution to the zero-sequence mutual inductance structure, the A-phase wiring board includes the first connecting portion, the first sensing portion, the first bending portion and the first wiring portion connected in sequence, and the C-phase wiring board includes the second connecting portion, the second sensing portion, the second bending portion and the second wiring portion connected in sequence; The first sensing portion is disposed in the first channel, the second sensing portion is disposed in the second channel, and the first bending portion and the second bending portion are extended in directions away from each other.

[0008] As a further optional solution for the zero-sequence mutual inductance structure, the width of the first wiring portion is greater than the width of the first inductive portion, and the width of the second wiring portion is greater than the width of the second inductive portion.

[0009] As a further optional solution to the zero-sequence mutual inductance structure, the A-phase contact includes a third connecting portion and a first contact portion connected to each other, and the C-phase contact includes a fourth connecting portion and a second contact portion connected to each other; Among them, the third connection part and the fourth connection part are extended in directions diverging from each other, one end of the third connection part facing the fourth connection part is connected to the first connection part, and the other end is connected to the first contact part, and one end of the fourth connection part facing the third connection part is connected to the second connection part, and the other end is connected to the second contact part.

[0010] As a further optional solution to the zero-sequence mutual inductance structure, the current transformer further includes a middle cover, which is arranged on a side of the casing away from the magnetic ring, and the middle cover and the casing are enclosed to form a first chamber and a second chamber; The first chamber is in communication with the first channel, and one end of the third connection portion facing the fourth connection portion is located in the first chamber; The second chamber is communicated with the third channel, and one end of the fourth connection portion facing the third connection portion is located in the second chamber.

[0011] As a further optional solution for the zero-sequence mutual inductance structure, the zero-sequence mutual inductance structure further includes a temperature detection component, and the temperature detection component is arranged on the phase-to-phase isolation component.

[0012] As a further optional solution to the zero-sequence mutual inductance structure, a wiring groove is provided on the cover; and / or A wire buckle is arranged on the cover shell.

[0013] As a further optional solution to the zero-sequence mutual inductance structure, the phase-to-phase isolation member includes a first insulating portion, a second insulating portion, a third insulating portion and a fourth insulating portion; The first insulating portion is arranged in a ring shape, and the magnetic ring is arranged around the first insulating portion; The second insulating portion, the third insulating portion and the fourth insulating portion are all located inside the first insulating portion, one ends of the second insulating portion, the third insulating portion and the fourth insulating portion are connected to each other, and the other ends of the second insulating portion, the third insulating portion and the fourth insulating portion are respectively connected to the first insulating portion; The first insulating part, the second insulating part and the third insulating part together form the first channel, the first insulating part, the third insulating part and the fourth insulating part together form the second channel, and the first insulating part, the second insulating part and the fourth insulating part together form the third channel.

[0014] Another object of the present invention is to provide a circuit breaker.

[0015] The present invention provides the following technical solutions: A circuit breaker comprises the above-mentioned zero-sequence mutual inductance structure.

[0016] The embodiments of the present invention have the following beneficial effects: In the above-mentioned zero-sequence mutual inductance structure, the phase-to-phase isolator on the cover is provided with a first channel, a second channel and a third channel. Correspondingly, the A-phase terminal block or the A-phase contact is provided in the first channel, the B-phase contact is provided in the second channel, and the C-phase terminal block or the C-phase contact is provided in the third channel. As a result, each phase line is separated by the phase-to-phase isolator designed in an integrated manner, the creepage distance is longer, the insulation performance is better, and it can meet the insulation requirements under high voltage and high current conditions and eliminate safety hazards. On this basis, in order to adapt to the phase-to-phase isolator designed in an integrated manner, the A-phase line and the C-phase line on both sides are both designed in a split manner, and are respectively divided into the A-phase terminal block and the A-phase contact, and the C-phase terminal block and the C-phase contact, so as to pass through the middle of the magnetic ring of the current transformer and complete the assembly.

[0017] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 The overall structural diagram of a zero-sequence mutual inductance structure provided by an embodiment of the present invention is shown; Figure 2 A schematic structural diagram of a zero-sequence mutual inductance structure provided by an embodiment of the present invention from another perspective is shown; Figure 3 A schematic structural diagram of a cover and an interphase isolator in a zero-sequence mutual inductance structure provided by an embodiment of the present invention is shown; Figure 4 A schematic structural diagram of a cover and an interphase isolator in a zero-sequence mutual inductance structure provided by an embodiment of the present invention from another perspective is shown; Figure 5 A schematic structural diagram of a phase line group in a zero-sequence mutual inductance structure provided by an embodiment of the present invention is shown; Figure 6 A schematic diagram showing the matching relationship between a cover shell and a middle cover in a zero-sequence mutual inductance structure provided by an embodiment of the present invention is shown; Figure 7 A schematic diagram of the internal structure of a zero-sequence mutual inductance structure provided by an embodiment of the present invention is shown; Figure 8 A schematic diagram of the overall structure of a circuit breaker provided by an embodiment of the present invention is shown.

[0020] Description of main component symbols: 10-zero sequence mutual inductance structure; 100-current transformer; 110-housing; 111-wiring groove; 112-wire buckle; 113-accommodating groove; 120-magnetic ring; 130-phase isolator; 131-first channel; 132-second channel; 133-third channel; 134-first insulating part; 135-second insulating part; 1351-groove; 136-third insulating part; 137-fourth insulating part; 140-middle cover; 141-first chamber; 142-second chamber; 200-phase line group; 210-A phase terminal block; 2 11-first connecting part; 212-first sensing part; 213-first bending part; 214-first wiring part; 220-A phase contact; 221-third connecting part; 222-first contact part; 230-B phase contact; 231-third wiring part; 232-third contact part; 240-C phase wiring board; 241-second connecting part; 242-second sensing part; 243-second bending part; 244-second wiring part; 250-C phase contact; 251-fourth connecting part; 252-second contact part; 300-temperature detection part. DETAILED DESCRIPTION

[0021] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0022] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. In contrast, when an element is referred to as being "directly on" another element, there is no intermediate element. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0023] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of the template are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0026] The technicians of the present application have found that in the related art, the three phase lines are very close to each other when passing through the magnetic ring 120 of the current transformer 100, and the phase insulation is poor. When the phases are isolated by wrapping insulating tape on the phase lines or adding insulating plugs between the phase lines, the operation steps are complicated, and the phase conduction may still occur under high voltage and high current conditions, which poses a safety hazard.

[0027] In addition, due to the size of the current transformer 100, the A-phase line and the C-phase line on both sides need to be bent toward the B-phase line in the middle, so that the three phase lines occupy less space when passing through the magnetic ring 120. However, the bent A-phase line and the C-phase line have the problem of relatively difficult penetration. During the penetration process, the position and angle need to be adjusted many times so that the various bending parts of the A-phase line and the C-phase line pass through the magnetic ring 120 one after another. At the same time, the size of the connection terminals of the A-phase line and the C-phase line is limited by the inner size of the magnetic ring 120, otherwise the penetration cannot be completed, which results in a narrow connection interface between the A-phase line and the C-phase line, and an increase in the connection temperature, which is not conducive to the long-term stable operation of the device.

[0028] Please also read Figure 1 and Figure 2 In view of the above problems, this embodiment provides a zero-sequence mutual inductance structure 10, including a current transformer 100 and a phase line group 200.

[0029] The current transformer 100 includes a housing 110 and a magnetic ring 120. The housing 110 is provided with an interphase isolator 130, and the interphase isolator 130 is provided with a first channel 131, a second channel 132 and a third channel 133. Accordingly, the magnetic ring 120 is provided around the interphase isolator 130.

[0030] In addition, the phase line group 200 includes an A-phase wiring board 210, an A-phase contact 220, a B-phase contact 230, a C-phase wiring board 240, and a C-phase contact 250. The A-phase wiring board 210 or the A-phase contact 220 is arranged in the first channel 131, and the A-phase wiring board 210 is connected to the A-phase contact 220. The B-phase contact 230 is arranged in the second channel 132. The C-phase wiring board 240 or the C-phase contact 250 is arranged in the third channel 133, and the C-phase wiring board 240 is connected to the C-phase contact 250.

[0031] In the above zero-sequence mutual inductance structure 10, the interphase isolator 130 on the housing 110 is provided with a first channel 131, a second channel 132 and a third channel 133. Correspondingly, the A-phase terminal block 210 or the A-phase contact 220 is provided in the first channel 131, the B-phase contact 230 is provided in the second channel 132, and the C-phase terminal block 240 or the C-phase contact 250 is provided in the third channel 133. Thus, each phase line is separated by the interphase isolator 130 designed in an integral manner, the creepage distance is longer, the insulation performance is better, and the insulation requirements under high voltage and high current working conditions can be met, eliminating safety hazards.

[0032] On this basis, in order to adapt to the integrated phase isolation part 130, the A phase line and the C phase line on both sides are designed to be split, and are respectively divided into the A phase terminal board 210 and the A phase contact 220, and the C phase terminal board 240 and the C phase contact 250, so as to pass through the middle of the magnetic ring 120 of the current transformer 100 to complete the assembly.

[0033] On the one hand, the A-phase wiring board 210 and the A-phase contact 220 can be plugged and connected from the front and rear sides of the housing 110 along the first direction (indicated by the X direction in the figure), and only one end of the two connected to each other needs to be aligned with the first channel 131; the C-phase wiring board 240 and the C-phase contact 250 can be plugged and connected from the front and rear sides of the housing 110 along the first direction, and only one end of the two connected to each other needs to be aligned with the third channel 133. This can avoid the problem of difficulty in passing the integrally bent A-phase line and C-phase line through the core.

[0034] On the other hand, the end of the A-phase wiring board 210 away from the A-phase contact 220 is used as the outlet of the A-phase line, and does not need to pass through the first channel 131; the end of the C-phase wiring board 240 away from the C-phase contact 250 is used as the outlet of the C-phase line, and does not need to pass through the third channel 133. Therefore, a larger size design can be adopted to obtain a wider wiring interface, thereby achieving a lower wiring temperature rise.

[0035] Please also read Figure 3 and Figure 4 In some embodiments, the interphase spacer 130 is composed of a first insulating portion 134 , a second insulating portion 135 , a third insulating portion 136 and a fourth insulating portion 137 .

[0036] Specifically, the first insulating portion 134 is arranged in a ring shape, and the magnetic ring 120 is arranged around the first insulating portion 134 .

[0037] The second insulating part 135, the third insulating part 136 and the fourth insulating part 137 are all located on the inner side of the first insulating part 134, one ends of the second insulating part 135, the third insulating part 136 and the fourth insulating part 137 are connected to each other, and the other ends of the second insulating part 135, the third insulating part 136 and the fourth insulating part 137 are respectively connected to the first insulating part 134.

[0038] The first insulating portion 134 , the second insulating portion 135 and the third insulating portion 136 enclose a first channel 131 ; the first insulating portion 134 , the third insulating portion 136 and the fourth insulating portion 137 enclose a second channel 132 ; the first insulating portion 134 , the second insulating portion 135 and the fourth insulating portion 137 enclose a third channel 133 .

[0039] In addition, the first channel 131 , the second channel 132 and the third channel 133 are all extended along the first direction.

[0040] Exemplarily, the main body of the housing 110 , the first insulating portion 134 , the second insulating portion 135 , the third insulating portion 136 , and the fourth insulating portion 137 are integrally injection molded.

[0041] See also Figure 5In some embodiments, the A-phase wiring board 210 or the A-phase contact 220 includes a first connection portion 211 . The A-phase wiring board 210 and the A-phase contact 220 are connected via the first connection portion 211 , and the first connection portion 211 is located in the first channel 131 . It is understandable that the A-phase terminal block 210 and the A-phase contact 220 are usually made of copper bars, and the thickness of the copper bars is generally 2.5-6 mm. When the A-phase terminal block 210 and the A-phase contact 220 are connected through the first connecting portion 211, the copper bar as the A-phase terminal block 210 and the copper bar as the A-phase contact 220 are stacked together and then bolted or welded. Along the first direction, the two stacked copper bars occupy a large space. Since the first connecting portion 211 is located in the first channel 131, the size of the current transformer 100 itself along the first direction can be fully utilized, avoiding the situation where the size of the device along the first direction is increased due to the split design of the A-phase line, which is conducive to adjusting the parameters such as the size of the current transformer 100 along the first direction under the given size, and optimizing the device characteristics.

[0042] Similarly, the C-phase wiring board 240 or the C-phase contact 250 includes a second connection portion 241 . The C-phase wiring board 240 and the C-phase contact 250 are connected via the second connection portion 241 , and the second connection portion 241 is located in the third channel 133 .

[0043] Specifically, the A-phase wiring board 210 includes a first connecting portion 211 , a first sensing portion 212 , a first bending portion 213 and a first wiring portion 214 which are connected in sequence.

[0044] The first sensing portion 212 is extended along the first direction and penetrates the first channel 131. The first connecting portion 211 is connected to an end of the first sensing portion 212 close to the A-phase contact 220, and the first bending portion 213 is connected to an end of the first sensing portion 212 away from the A-phase contact 220, and the first connecting portion 211 and the first bending portion 213 are both perpendicular to the first direction.

[0045] Similarly, the C-phase wiring board 240 includes a second connecting portion 241 , a second sensing portion 242 , a second bending portion 243 and a second wiring portion 244 which are connected in sequence.

[0046] The second sensing portion 242 is extended along the second direction and penetrates the third channel 133. The second connecting portion 241 is connected to an end of the second sensing portion 242 close to the C-phase contact 250, and the second bending portion 243 is connected to an end of the second sensing portion 242 away from the C-phase contact 250, and the second connecting portion 241 and the second bending portion 243 are both perpendicular to the first direction.

[0047] In addition, the first bending portion 213 and the second bending portion 243 are extended in directions away from each other, specifically in the second direction, which is shown in the Y direction in the figure. One end of the first bending portion 213 facing the second bending portion 243 is connected to the first sensing portion 212, and the other end is connected to the first wiring portion 214. One end of the second bending portion 243 facing the first bending portion 213 is connected to the second sensing portion 242, and the other end is connected to the second wiring portion 244.

[0048] When in use, the magnetic ring 120 surrounds the first induction part 212, the second induction part 242 and the periphery of the B-phase contact 230. When the vector sum of the currents in the first induction part 212, the second induction part 242 and the B-phase contact 230 is not zero, the generated zero-sequence current excites the induced magnetic field, thereby generating an induced current in the secondary winding of the current transformer 100, thereby realizing the monitoring of the circuit where the phase line group 200 is located.

[0049] Furthermore, the width of the first wiring portion 214 is greater than the width of the first sensing portion 212 , and the width of the second wiring portion 244 is greater than the width of the second sensing portion 242 .

[0050] It can be understood that the width of the first sensing part 212 is limited by the cross-sectional size of the first channel 131. When the A phase line adopts a split design, the first wiring part 214 does not need to pass through the first channel 131, so the width of the first wiring part 214 can be made larger to obtain a wider wiring interface, thereby achieving a lower wiring temperature rise.

[0051] Similarly, the width of the second sensing portion 242 is limited by the cross-sectional size of the third channel 133. When the C phase line adopts a split design, the second wiring portion 244 does not need to pass through the third channel 133, so the width of the second wiring portion 244 can be made larger, and a wider wiring interface can also be obtained, thereby achieving a lower wiring temperature rise.

[0052] Specifically, the A-phase contact 220 includes a third connection portion 221 and a first contact portion 222 connected to each other, and the C-phase contact 250 includes a fourth connection portion 251 and a second contact portion 252 connected to each other.

[0053] The third connection portion 221 and the fourth connection portion 251 are extended in directions away from each other, specifically, in the second direction. One end of the third connection portion 221 facing the fourth connection portion 251 is connected to the first connection portion 211, and the other end is connected to the first contact portion 222. One end of the fourth connection portion 251 facing the third connection portion 221 is connected to the second connection portion 241, and the other end is connected to the second contact portion 252.

[0054] It can be understood that one end of the third connection portion 221 facing the fourth connection portion 251 is perpendicular to the first direction and is located at the opening of the first channel 131. The first connection portion 211 is located at the end of the first channel 131 facing the A-phase contact 220 and is connected to the third connection portion 221 after being overlapped.

[0055] Similarly, one end of the fourth connection portion 251 facing the third connection portion 221 is perpendicular to the first direction and is located at the opening of the third channel 133. The second connection portion 241 is located at the end of the third channel 133 facing the C-phase contact 250 and is connected to the fourth connection portion 251 after being overlapped.

[0056] Please also read Figure 6 and Figure 7 Furthermore, the current transformer 100 further includes a middle cover 140 . The middle cover 140 is disposed on a side of the housing 110 away from the magnetic ring 120 , and the middle cover 140 and the housing 110 are enclosed to form a first chamber 141 and a second chamber 142 .

[0057] The first chamber 141 is communicated with the first channel 131 , and one end of the third connection portion 221 facing the fourth connection portion 251 is located in the first chamber 141 .

[0058] The second chamber 142 is communicated with the third channel 133 , and one end of the fourth connection portion 251 facing the third connection portion 221 is located in the second chamber 142 .

[0059] The middle cover 140 cooperates with the cover shell 110 to isolate the third connecting part 221 in the first chamber 141, isolate the fourth connecting part 251 in the second chamber 142, and isolate the B phase contact 230 outside, which can better achieve phase isolation and maintain the rear end closure of each pole cavity, which is beneficial to improve the breaking capacity of the device.

[0060] Exemplarily, the middle cover 140 and the casing 110 are integrally injection molded.

[0061] Please refer again Figure 5 In some embodiments, the B-phase contact 230 includes a third wiring portion 231 and a third contact portion 232 .

[0062] The first wiring portion 214, the third wiring portion 231 and the second wiring portion 244 are sequentially arranged along the second direction as three outgoing terminals of the phase line group 200. The first contact portion 222, the third contact portion 232 and the second contact portion 252 are sequentially arranged along the second direction as three incoming terminals of the phase line group 200.

[0063] Please refer again Figure 1In some embodiments, considering that the split-design A-phase line and C-phase line may have poor contact at the connection, resulting in greater resistance and more heat generation at the connection, which in turn causes the cover 110 to melt. In this regard, the zero-sequence mutual inductance structure 10 further includes a temperature detection element 300, and the temperature detection element 300 is disposed on the interphase isolation element 130.

[0064] When in use, the temperature detection member 300 disposed on the interphase isolating member 130 is adjacent to the first connection portion 211, the second connection portion 241, the third connection portion 221, and the fourth connection portion 251. When the connection between the first connection portion 211 and the third connection portion 221 and the connection between the second connection portion 241 and the fourth connection portion 251 show a significant temperature rise due to large resistance, the temperature detection member 300 can detect it in time, so that the control module of the device is disconnected in time when the temperature exceeds the preset value to prevent the device from burning.

[0065] Please combine Figure 3 , illustratively, a groove 1351 is provided on the second insulating portion 135 . The temperature detection member 300 uses a temperature sensing probe, and the temperature sensing probe is embedded in the groove 1351 .

[0066] Please refer again Figure 3 and Figure 4 In some embodiments, a wiring groove 111 is provided on the cover 110; and / or a wire buckle 112 is provided on the cover 110.

[0067] When in use, the cover 110 provided with the wiring groove 111 and / or the wire clip 112 can be used to gather the cables in the current transformer 100 , and the cover 110 can be used to achieve regular wiring.

[0068] Specifically, the housing 110 is provided with a receiving groove 113 on one side facing the magnetic ring 120. The receiving groove 113 is arranged around the phase isolation member 130, and the magnetic ring 120 is embedded in the receiving groove 113. Meanwhile, the wiring groove 111 is arranged at the periphery of the receiving groove 113 and communicates with the receiving groove 113.

[0069] In addition, a plurality of wire ties 112 are provided, and the plurality of wire ties 112 are provided on the outer surface of the housing 110 and arranged along the second direction.

[0070] In summary, the above-mentioned zero-sequence mutual inductance structure 10 separates each phase line by setting an interphase isolator 130 on the cover 110, without the need for production steps such as winding insulating tape and adding insulating plugs. The creepage distance is longer and the insulation performance is better. The insulation capacity of the product is improved in a limited space, and it can meet the insulation requirements under high voltage and high current conditions, eliminate safety hazards, and greatly improve the safety performance of the product. At the same time, the A-phase line and the C-phase line on both sides are split in design, which can avoid the problem of difficulty in passing the A-phase line and the C-phase line with one-piece bending, and obtain a wider wiring interface, thereby achieving a lower wiring temperature rise.

[0071] See also Figure 8 This embodiment also provides a circuit breaker, including the above-mentioned zero-sequence mutual inductance structure 10.

[0072] In all examples shown and described herein, any specific values ​​should be interpreted as merely exemplary and not as limiting, and thus other examples of the exemplary embodiments may have different values.

[0073] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0074] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A zero-sequence mutual inductance structure, characterized in that: It comprises a current transformer (100) and a phase line group (200); The current transformer (100) comprises a housing (110) and a magnetic ring (120); an interphase isolating member (130) is arranged on the housing (110); a first channel (131), a second channel (132) and a third channel (133) are arranged on the interphase isolating member (130); and the magnetic ring (120) is arranged around the interphase isolating member (130); The phase line group (200) comprises an A-phase wiring board (210), an A-phase contact (220), a B-phase contact (230), a C-phase wiring board (240) and a C-phase contact (250); the A-phase wiring board (210) or the A-phase contact (220) is arranged in the first channel (131); the A-phase wiring board (210) is connected to the A-phase contact (220); the B-phase contact (230) is arranged in the second channel (132); the C-phase wiring board (240) or the C-phase contact (250) is arranged in the third channel (133); the C-phase wiring board (240) is connected to the C-phase contact (250).

2. The zero-sequence mutual inductance structure according to claim 1, characterized in that: The A-phase wiring board (210) or the A-phase contact (220) comprises a first connection portion (211), the A-phase wiring board (210) and the A-phase contact (220) are connected via the first connection portion (211), and the first connection portion (211) is located in the first channel (131); The C-phase wiring board (240) or the C-phase contact (250) comprises a second connection portion (241), the C-phase wiring board (240) and the C-phase contact (250) are connected via the second connection portion (241), and the second connection portion (241) is located in the third channel (133).

3. The zero-sequence mutual inductance structure according to claim 2, characterized in that: The A-phase wiring board (210) comprises the first connecting portion (211), the first sensing portion (212), the first bending portion (213) and the first wiring portion (214) which are connected in sequence, and the C-phase wiring board (240) comprises the second connecting portion (241), the second sensing portion (242), the second bending portion (243) and the second wiring portion (244) which are connected in sequence; The first sensing portion (212) is disposed in the first channel (131), the second sensing portion (242) is disposed in the second channel (132), and the first bending portion (213) and the second bending portion (243) are extended in directions diverging from each other.

4. The zero-sequence mutual inductance structure according to claim 3, characterized in that: The width of the first wiring portion (214) is greater than the width of the first sensing portion (212), and the width of the second wiring portion (244) is greater than the width of the second sensing portion (242).

5. The zero-sequence mutual inductance structure according to claim 3, characterized in that: The A-phase contact (220) comprises a third connection portion (221) and a first contact portion (222) connected to each other, and the C-phase contact (250) comprises a fourth connection portion (251) and a second contact portion (252) connected to each other; The third connection part (221) and the fourth connection part (251) are extended in directions diverging from each other, one end of the third connection part (221) facing the fourth connection part (251) is connected to the first connection part (211), and the other end is connected to the first contact part (222), and one end of the fourth connection part (251) facing the third connection part (221) is connected to the second connection part (241), and the other end is connected to the second contact part (252).

6. The zero-sequence mutual inductance structure according to claim 5, characterized in that: The current transformer (100) further comprises a middle cover (140), wherein the middle cover (140) is arranged on a side of the casing (110) away from the magnetic ring (120), and the middle cover (140) and the casing (110) are enclosed to form a first chamber (141) and a second chamber (142); The first chamber (141) is in communication with the first channel (131), and one end of the third connection portion (221) facing the fourth connection portion (251) is located in the first chamber (141); The second chamber (142) is in communication with the third channel (133), and one end of the fourth connection portion (251) facing the third connection portion (221) is located in the second chamber (142).

7. The zero-sequence mutual inductance structure according to any one of claims 1 to 6, characterized in that: The zero-sequence mutual inductance structure (10) further comprises a temperature detection component (300), wherein the temperature detection component (300) is arranged on the interphase isolation component (130).

8. The zero-sequence mutual inductance structure according to any one of claims 1 to 6, characterized in that: The cover shell (110) is provided with a wiring groove (111); and / or The cover shell (110) is provided with a wire buckle (112).

9. The zero-sequence mutual inductance structure according to any one of claims 1 to 6, characterized in that: The interphase isolator (130) comprises a first insulating portion (134), a second insulating portion (135), a third insulating portion (136) and a fourth insulating portion (137); The first insulating portion (134) is arranged in a ring shape, and the magnetic ring (120) is arranged around the first insulating portion (134); The second insulating portion (135), the third insulating portion (136) and the fourth insulating portion (137) are all located inside the first insulating portion (134); one ends of the second insulating portion (135), the third insulating portion (136) and the fourth insulating portion (137) are connected to each other, and the other ends of the second insulating portion (135), the third insulating portion (136) and the fourth insulating portion (137) are respectively connected to the first insulating portion (134); The first insulating portion (134), the second insulating portion (135) and the third insulating portion (136) together form the first channel (131); the first insulating portion (134), the third insulating portion (136) and the fourth insulating portion (137) together form the second channel (132); and the first insulating portion (134), the second insulating portion (135) and the fourth insulating portion (137) together form the third channel (133).

10. A circuit breaker, characterized in that: It comprises the zero-sequence mutual inductance structure (10) described in any one of claims 1 to 9.

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