EP3912238A1

EP3912238A1 - Supporting mechanism for busbar and switchgear

Info

Publication number: EP3912238A1
Application number: EP19909781.7A
Authority: EP
Inventors: Yicong LIN; Bin SHAN; Zhirong ZHENG; Tian Lin
Original assignee: ABB Schweiz AG
Current assignee: ABB Schweiz AG
Priority date: 2019-01-18
Filing date: 2019-01-18
Publication date: 2021-11-24
Also published as: WO2020147114A1; CN113169531B; CN113169531A; EP3912238A4

Abstract

Embodiments of the present disclosure provide a supporting mechanism for busbars. The supporting mechanism comprises a middle part comprising at least two sets of first slots arranged in pairs on two sides of the middle part, each set of first slots passing through the middle part in a direction perpendicular to an extending direction of the middle part; a first side part and a second side part arranged symmetrically and adjacent to the middle part, the first and second side parts each comprising at least a set of second slots aligned with the respective set of first slots to enable the busbars to extend in the direction to be partially received in sets the first and second slots; and a fixing assembly coupled to the middle part and the first and second side parts, the fixing assembly operable to move the first and second side parts towards the middle part to clamp the busbars. The supporting mechanisms increase heat dissipation area of busbars, improving the heat dissipation. Furthermore, branch busbars may be attached to main busbars with fixing elements passing through the gaps between the busbars arranged on two sides of the middle part, facilitating the assembly of the branch busbars. In addition, no hole in the main busbars for connecting the branch busbars is needed, improving the standardization degree and connection reliability.

Description

SUPPORTING MECHANISM FOR BUSBAR AND SWITCHGEAR

FIELD

Embodiments of the present disclosure relate to a supporting mechanism for busbars as well as associated switchgear.

BACKGROUND

Busbars are essential parts of switchgears and control equipment. The busbars are usually supported by a busbar supporting mechanism arranged in the switchgear. The busbar supporting mechanism is a common electrical accessory in the switchgear and control equipment. The main function of the busbar supporting mechanism is to support, insulate the busbars and withstand electrical and thermal forces.
In the traditional switchgear, particularly the low-voltage power distribution cabinet, the busbars are generally arranged in a single horizontal parallel arrangement. In such an arrangement, the busbars are arranged such that largest area surfaces thereof are adjacent to each other. Since the largest area surface is an effective heat dissipation surface, the above arrangement makes the heat of the busbars difficult to dissipate.
Furthermore, as well known, the busbars in the switchgear typically comprises main busbars and branch busbars. In convention solutions, the branch busbars need to be connected to the main busbars through connection holes on the main busbars. That is, the connection holes are necessary when coupling the branch busbars to the main busbars. In this event, during the assembly process, the connection holes should be drilled at different positions on the main busbars of different phases to connect with the branch busbars, so that the standardization degree of the main busbar is reduced, and the assembly efficiency is inevitably affected.
SUMMARY
The known busbar supporting mechanisms have the problems of affecting heat dissipation, inconvenient installation, and the risk of overheating. In order to at least partially address the above and other potential problems, embodiments of the present disclosure provide a supporting mechanism for busbars.
In a first aspect, a supporting mechanism for busbars is provided. The supporting mechanism comprises a middle part comprising at least two sets of first slot arranged in pairs on two sides of the middle part, each set of first slots passing through the middle part in a direction perpendicular to an extending direction of the middle part; a first side part and a second side part arranged symmetrically and adjacent to the middle part, the first and second side parts each comprising at least a set of second slots aligned with the respective set of first slots to enable the busbars to extend in the direction to be partially received in first slot and second slot; and a fixing assembly coupled to the middle part and the first and second side parts, the fixing assembly operable to move the first and second side parts towards the middle part to clamp the busbars.
By using the middle part and the first and second side parts, the supporting mechanism allows the busbars to be symmetrically arranged on two sides of the middle part. That is, the busbars are arranged in two vertical layers with largest area surfaces aligned with each other, improving the heat dissipation of busbars. Furthermore, branch busbars may be attached to main busbars with fixing elements passing through the gaps between the busbars arranged on two sides of the middle part, facilitating the assembly of the branch busbars. In addition, no hole in the main busbars for connecting the branch busbars is needed, improving the standardization degree and connection reliability of busbars.
In some embodiments, each set of first slots comprises a plurality of first slots parallel to each other, and each set of second slots comprises a plurality of second slots parallel to each other, and each second slot is aligned with the respective first slot to at least partially receive one of the busbars. In this way, either the number or the sizes of busbars in each set of slots may be adjusted, improving the flexibility of the busbar arrangement.
In some embodiments, each of the first and second slots is sized to allow largest area surfaces of a first busbar and a second busbar symmetrically arranged on the two sides of the middle part to be aligned. This arrangement ensures that the busbars with the largest area surface aligned with each other may be received in the middle and second slots in a more stable way, improving heat dissipation and current carrying capacity of the busbars.
In some embodiments, a height of the middle part between first and second slot sets is configured to allow a fixing element to be arranged between the first and second busbars, and wherein the fixing element is operable to electrically couple a branch busbar to the first and second busbars. As a result, the fixing element may pass through the gap between the first and second busbars to couple the main busbars to the branch busbars, without drilling holes in the main busbars. In this way, the assembly of the busbars is simpler and more accurate, and the positioning of the busbar is also more convenient.
In some embodiments, a distance between the adjacent first slots is smaller than a distance between the adjacent sets of first slot in the extending direction. With this arrangement, the heat of the busbars between the different phases may be more easily dissipated, improving the current carrying capacity of the busbars.
In some embodiments, the fixing assembly comprises a first coupling plate adjacent to the first side part; a second coupling plate parallel to the first coupling plate and adjacent to the second side part; and a plurality of adjusting assemblies perpendicular to and between the first and second coupling plates, the adjusting assembly being operable to move the first and second coupling plates to move the pair of side parts towards the middle part. In this way, the assembly of the supporting mechanism may be easier.
In some embodiments, the first side part comprises a first coupling groove extending in the extending direction and adapted to receive the first coupling plate, and the second side part comprises a second coupling groove extending in the extending direction and adapted to receive the second coupling plate. This simplified structure allows a more convenient positioning between the side parts and the first and second coupling plates.
In some embodiments, the adjusting assembly comprises an adjusting shaft comprising two ends adjacent or coupled to the first and second coupling plates; and a pair of engaging members, each of the pair of engaging members coupled to one of the two ends of the adjusting shaft to move the first and second coupling plates. In this way, a distance between the side parts and middle part and clamping force on the busbars may be adjusted in a more simple way.
In some embodiments, the middle part comprises at least one through-hole for the adjusting shaft to pass through.
In a second aspect, a switchgear comprising a supporting mechanism as mentioned above is provided.
It is to be understood that the Summary is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the description below.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objectives, features and advantages of the present disclosure will become more apparent through more detailed depiction of example embodiments of the present disclosure in conjunction with the accompanying drawings, wherein in the example embodiments of the present disclosure, same reference numerals usually represent same components.
FIG. 1 shows a perspective view of a supporting mechanism for busbars according to embodiments of the present disclosure;
FIGs. 2A and 2B show perspective views of supporting mechanisms for busbars according to embodiments of the present disclosure;
FIG. 3 shows an exploded view of a supporting mechanism for busbars according to embodiments of the present disclosure;
FIG. 4 shows a perspective view of a middle part of a supporting mechanism for busbars according to embodiments of the present disclosure;
FIGs. 5 and 6 show perspective views of first and second side parts of a supporting mechanism for busbars according to embodiments of the present disclosure; and
FIG. 7 shows a perspective view of a supporting mechanism for busbars according to embodiments of the present disclosure, with branch busbars are attached on main busbars.
Throughout the drawings, the same or similar reference symbols are used to indicate the same or similar elements.

DETAILED DESCRIPTION

The present disclosure will now be discussed with reference to several example embodiments. It is to be understood these embodiments are discussed only for the purpose of enabling those skilled persons in the art to better understand and thus implement the present disclosure, rather than suggesting any limitations on the scope of the subject matter.
As used herein, the term “comprises” and its variants are to be read as open terms that mean “comprises, but is not limited to. ” The term “based on” is to be read as “based at least in part on. ” The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” The terms “first, ” “second, ” and the like may refer to different or same objects. Other definitions, explicit and implicit, may be comprised below. A definition of a term is consistent throughout the description unless the context clearly indicates otherwise.
As well known, during operation of a switchgear, busbars in the switchgear generate heat due to the current carried by the busbars, resulting in an increase in temperature. Largest area surfaces of a busbar can dissipate the heat generated by the load on the busbar. In the conventional solutions, the busbars are arranged in supporting mechanisms of a switchgear in a single horizontal parallel arrangement. That is, in such an arrangement, the busbars are arranged in a single horizontal layer with the largest area surfaces adjacent to each other, resulting in poor heat dissipation ofbusbars. In this event, the heat dissipation of the busbars between different phases and between the busbars of the same phase will affect each other, reducing current carrying capacity of the busbars.
Furthermore, in conventional solutions, due to the single layer arrangement of main busbars, the main busbars need to be opened connection holes to allow branch busbars to be coupled to the main busbars. During assembly of the branch busbars on the main busbars, alignment of these holes of the main busbars in one phase is needed, resulting in lower assembly efficiency. In the meantime, overheating may be caused due to the joint machining error and assembly error between the main and branch busbars. For example, in case that the positions of the main and branch busbars are offset, undue assembly stress between the main and branch busbars may cause a sharp rise in the temperature of the busbars. In addition, this also seriously reduces the reliability of the connection between the main and branch busbars.
In order to at least partially address the above and other potential problems, embodiments of the present disclosure provide a supporting mechanism 100 for busbars 200.
FIG. 1 shows a perspective view of a supporting mechanism 100 for busbars 200 according to embodiments of the present disclosure. As shown, the supporting mechanism 100 generally comprises a fixing assembly 103, a middle part 101 and two side parts, namely, a first side part 1021 and a second side part 1022 symmetrically arranged adjacent to the middle part 101. The middle part 101 comprises at least two sets of first slot 1011 in pairs. The two sets of first slot 1011 are symmetrically arranged on two sides of the middle part 101 adjacent to the first and second side parts 1021, 1022.
As shown, in some embodiments, there may be eight sets of first slot 1011, a number of which may correspond to twice the number of phases in the switchgear. Each of the first and second side parts 1021, 1022 comprises a corresponding number of sets of second slot 1023, as shown in FIG. 1. It should be understood that the above embodiments where there are eight sets of first slot 1011 are merely for illustration, without suggesting any limitations as to the scope of the present disclosure. Any other suitable numbers and arrangements are possible as well. For example, in some alternative embodiments, there may be four or six sets of first slot 1011 in pairs as well.
Each set of the first and second slots 1011, 1023 respectively passes through the middle part and side parts in a direction D1 perpendicular to an extending direction D2 of the middle part 101. Furthermore, the set of second slots 1023 is aligned with the respective set of first slots 1011, allowing the busbars 200 partially received in sets of the first slot and second slot 1011, 1023.
The middle part 101 and the first and second side parts 1021, 1022 are coupled to each other with the fixing assembly 103. The fixing assembly 103 can move the first and second side parts 1021, 1022 respectively towards the middle part 101 to clamp the busbars 200 therebetween.
In this way, the busbars 200 extending in the direction D1 are symmetrically arranged on both sides of the middle part 101. That is, the busbars 200 are arranged in two rows, one group ofbusbars (referred to as first busbar 201) is arranged in an upper row between the middle part 101 and the first side part 1021, and another (referred to as second busbar 202) is in a lower row between the middle part 101 and the second side part 1022, as shown in FIGs. 2A and 2B. This enables the heat dissipation area to increase significantly, so that the heat generated by the carried current can be dissipated as quickly as possible.
In the case where the carried current is small, only one of the busbars may be arranged in one set of the first and second slots 1011, 1023, as shown in FIG. 2B. Compared to the arrangement of two busbars with the largest area surfaces adjacent to each other in the conventional solutions, this can significantly reduce the busbar temperature and increase current carrying capacity of one busbar. Alternatively, in the case where the carried current is large, the number of busbars in each set of slots may be appropriately increased.
For example, it is assumed that four busbars may be required when the carried current is greater than a certain threshold, in the conventional solutions, the four busbars are arranged in a single horizontal row. On the contrary, according to embodiments of the present disclosure, two of the four busbars are arranged in the upper row and the other two are arranged in the lower row. As a result, a temperature of the busbars arranged in two vertical rows can be significantly reduced due to the increased heat dissipation area, improving the current carrying capacity of the busbars. Furthermore, such a supporting mechanism can also facilitate the assembly of the branch busbars on the main busbars and thus increase the stability of the system, which will be discussed further below.
Furthermore, besides the number of the busbars in each set of slots, a size of busbar may also be adjustable. For example, in some embodiments, the busbars having different sizes, such as 60X10, 80X10, 100X8, 125X8 or the like, may be exchanged according to the magnitude of the carried current. For example, in the case where the carried current is small, small sized busbars may be used. Alternatively, in the case where the carried current is small is large, large sized busbars may be used without changing the number of the busbars. In this way, the flexibility of the busbar arrangement is further improved.
In some embodiments, the sets of first slot and second slot 1011, 1023 may respectively comprise a plurality of slots each for receiving one of the busbars 200, as shown in FIGs. 1, 3-6. Specifically, the set of first slots 1011 may comprise a plurality of first slots 1013 parallel to each other and the set of second slots 1023 may comprise a plurality of second slots 1026 parallel to each other. This may facilitate the update and maintenance of the supporting mechanism 100. For example, in case the carried current is increased, one or more busbars 200 may be simply added in the first and second slots 1013, 1026 adjacent to the slots in which busbars have already been received.
As mentioned above, each of the first and second slot sets 1011, 1023 may be used to receive one or more busbars 200 in one phase. In some embodiments, in order to reduce the heat interference between different phases, a distance between the adjacent first slots 1013 may be smaller than a distance between the adjacent sets of first slot 1011 in the extending direction D2, as shown in FIG. 3. Similarly, since each of the first slots 1013 is aligned with the respective second slot 1026, the distances between adjacent second slots 1026 and between adjacent sets of second slot 1012 may have the same arrangement as above.
In some embodiments, each of the middle and second slots 1013, 1026 may be sized to allow the largest area surfaces of the first and second busbars 201, 202 to be aligned. For example, in some embodiments, a width of each of the middle and second slots 1013, 1026 may be substantially equal to a thickness of a busbar 200. This can prevent the busbar 200 received in the middle and second slots 1013, 1026 from shaking, further increasing the stability of the supporting mechanism 200 and reducing the risk of overheating.
In some embodiments, the fixing assembly 103 for fixing the middle and side parts may comprise two coupling plate, namely, a first coupling plate 1031 adjacent to the first side part 1021 and a second coupling plate 1032 adjacent to the second side part 1022. The first and second coupling plates 1031, 1032 are parallel to each other. The fixing assembly 103 may further comprise a plurality of adjusting assemblies 1033 perpendicular to and between the first and second coupling plates 1031, 1032. The adjusting assemblies 1033 may be used to move the first and second coupling plate 1031, 1032 and thus to move the first and second side parts 1021, 1022 towards the middle part 101.
In this way, the distance between the side part and the middle part 101 and thus the clamping force on the busbars 200 may be adjusted conveniently. Furthermore, with the above arrangement, the supporting mechanism 100 can ensure stable assembly of the busbars without requiring high machining accuracy of the supporting mechanism 100. This further reduces the manufacture and assembly costs.
In order to further facilitate the assembly of the supporting mechanism 100, the first and side parts 1021, 1022 may respectively comprise a first coupling groove 1024 and a second coupling groove 1025 extending in the extending direction D2, as shown in FIGs. 5 and 6. The first and second grooves 1024, 1025 may respectively receive the first and second coupling plates 1031, 1032, increasing the positioning accuracy of the first and second coupling plates 1031, 1032 in a simple way.
In some embodiments, the adjusting assembly 1033 may comprise an adjusting shaft 1034 and a pair of engaging members 1035, as shown in FIG. 3. Two ends of the adjusting shaft 1034 may be adjacent or coupled to the first and second coupling plates 1031, 1032, respectively. For example, in some embodiments, the two ends of the adjusting shafts 1034 may comprise bolts that pass through the first and second coupling plates 1031, 1032, and the engaging member 1035 may be nuts engaged with the bolts. In this way, the adjusting assembly 1033 can be implemented using standard components, further reducing costs.
It should be understood that the embodiments where the bolts and nuts are used in the adjusting assembly 1033 are merely for illustration, without suggesting any limitations as to the scope of the present disclosure. Any other suitable structures and arrangements are possible as well. For example, in some alternative embodiments, as shown in FIG. 3, a first end of the adjusting shaft 1034 may be a bolt and the second end may have an inner screw hole. Accordingly, the engaging member 1035 engaged with the first end may be a nut and the one engaged with the second end may be a bolt. This may increase the assembly flexibility of the supporting mechanism 100 and facilitate the distance adjustment between the side part and middle part 101.
Numbers of the adjusting assemblies 1033 may be set according to the length of the supporting mechanism 100 in the extending direction D2. For example, in some embodiments, as shown in FIG. 3, there are five adjusting assemblies 1033, in which two adjusting assemblies 1033 may be arranged on two ends of the supporting mechanism 100 in the extending direction D2 and the other three are arranged between the adjacent sets of slot. In this way, the forces on the side and middle plates may be more evenly balanced, thereby increasing the structural stability of the support mechanism 100. In some embodiments, the middle part 101 may comprise at least one through-hole 1012 for the adjusting shaft 1034 to pass through.
It should be understood that the above embodiments where there are five adjusting assemblies 1033 are merely for illustration, without suggesting any limitations as to the scope of the present disclosure. Any other suitable numbers and arrangements are possible as well. For example, in some alternative embodiments, the adjusting assemblies 1033 may be merely arranged on two ends of the supporting mechanism 100 in the extending direction D2.
In some embodiments, the first and second coupling plates 1031, 1032 may have a U-shaped cross-section in a plane perpendicular to the extending direction D2, as shown in FIG. 3. In one hand, the U-shaped coupling plate may allow the engaging members 1035 to be hidden in the plate. In the other hand and more importantly, the U-shaped cross-section may increase the strength of the first and second coupling plates 1031, 1032, thereby further increasing the structural stability of the supporting mechanism 100.
In some embodiments, as shown in FIG. 3, any of the first and second coupling plates 1031, 1032 may comprise coupling means to allow the supporting mechanism 100 to be fixed in the switchgear. The coupling means may be integrally formed on the first or second coupling plates 1031, 1032 by bending or the like. In this way, the supporting mechanism 100 may be fixed in the switchgear more conveniently.
Moreover, the above arrangement of the supporting mechanism 100 may also enable the branch busbars 203 to be coupled to the main busbars without opening holes in the main busbars. For example, in some embodiments, as shown in FIG. 7, the branch busbars 203 may be coupled to the main busbars by using fixing elements 104 arranged between the first and second busbars 201, 202.
In this way, since the holes in the main busbars for coupling the branch busbars are omitted, the size limit of the busbars may be further reduced. In this way, the busbars may be easier to be standardized. Furthermore, there is no assembly error and machining error of the holes at all, which reduces the structural stress of the support mechanism 100 and improves the stability of the support mechanism 100. In addition, the problem of overheating is also avoided due to the reduced assembly requirements.
The branch bus bars in the different phases may be arranged at mutually staggered positions in the direction D1, as shown in FIG. 7. This may further facilitate the heat dissipation in branch busbars 203. In some embodiments, in order to ensure that the fixing elements 104 to be arranged between the first and second busbars 201, 202, a height of the middle part between sets of first and second slot 1011, 1023 is sized to allow a fixing element 104 to pass through the gap between the first and second busbars 201, 202, as shown FIG. 7. This can be achieved without too high machining accuracy, and thus reduces the manufacture and assembly costs.
It should be appreciated that the above detailed embodiments of the present disclosure are only to exemplify or explain principles of the present disclosure and not to limit the present disclosure. Therefore, any modifications, equivalent alternatives and improvement, etc. without departing from the spirit and scope of the present disclosure shall be comprised in the scope of protection of the present disclosure. Meanwhile, appended claims of the present disclosure aim to cover all the variations and modifications falling under the scope and boundary of the claims or equivalents of the scope and boundary.

Claims

A supporting mechanism (100) for busbars (200) , comprising:

a middle part (101) comprising at least two sets of first slots (1011) arranged in pairs on two sides of the middle part (101) , each set of first slots (1011) passing through the middle part (101) in a direction (D1) perpendicular to an extending direction (D2) of the middle part (101) ;

a first side part (1021) and a second side part (1022) arranged symmetrically and adjacent to the middle part (101) , the first and second side parts (1021, 1022) each comprising at least a set of second slots (1023) aligned with the respective set of first slots (1011) to enable the busbars (200) to extend in the direction (D1) to be partially received in first and second slots (1013, 1026) ; and

a fixing assembly (103) coupled to the middle part (101) and the first and second side parts (1021, 1022) , the fixing assembly (103) operable to move the first and second side parts (1021, 1022) towards the middle part (101) to clamp the busbars (200) .
The supporting mechanism (100) of claim 1, wherein each set of first slots (1011) comprises a plurality of first slots (1013) parallel to each other, and

each set of second slots (1023) comprises a plurality of second slots (1026) parallel to each other, and

each second slot (1026) is aligned with the respective first slot (1013) to at least partially receive one of the busbars (200) .
The supporting mechanism (100) of claim 2, wherein each of the first and second slots (1013, 1026) is sized to allow largest area surfaces of a first busbar (201) and a second busbar (202) symmetrically arranged on the two sides of the middle part (101) to be aligned.
The supporting mechanism (100) of claim 3, wherein a height of the middle part (101) between first and second slot sets (1011, 1023) is configured to allow a fixing element (104) to be arranged between the first and second busbars (201, 202) , and

wherein the fixing element (104) is operable to electrically couple a branch busbar (203) to the first and second busbars (201, 202) .
The supporting mechanism (100) of claim 2, wherein a distance between the adjacent first slots (1013) is smaller than a distance between the adjacent sets of first slot (1011) in the extending direction (D2) .
The supporting mechanism (100) of claim 1, wherein the fixing assembly (103) comprises:

a first coupling plate (1031) adjacent to the first side part (1021 ) ;

a second coupling plate (1032) parallel to the first coupling plate (1031) and adjacent to the second side part (1022) ; and

a plurality of adjusting assemblies (1033) perpendicular to and between the first and second coupling plates (1031, 1032) , the adjusting assembly (1033) being operable to move the first and second coupling plates (1031, 1032) to move the first and second side parts (1021, 1022) towards the middle part (101) .
The supporting mechanism (100) of claim 6, wherein the first side part (1021) comprises a first coupling groove (1024) extending in the extending direction (D2) and adapted to receive the first coupling plate (1031) , and

the second side part (1022) comprises a second coupling groove (1025) extending in the extending direction (D2) and adapted to receive the second coupling plate (1032) .
The supporting mechanism (100) of claim 6, wherein the adjusting assembly (1033) comprises:

an adjusting shaft (1034) comprising two ends adjacent or coupled to the first and second coupling plates (1031, 1032) ; and

a pair of engaging members (1035) , each of the pair of engaging members (1035) coupled to one of the two ends of the adjusting shaft (1034) to move the first and second coupling plates (1031, 1032) .
The supporting mechanism (100) of claim 8, wherein the middle part (101) comprises at least one through-hole (1012) for the adjusting shaft (1034) to pass through.
A switchgear comprising a supporting mechanism of any of claims 1-9.