Busbar positioning structure and electrical equipment

Abstract

A busbar positioning structure (1) comprises: a pair of terminal blocks (3, 4), each of which is provided with a busbar (P, N) for connecting two electrical components (e.g., a DC capacitor (C) and a power module (11)) of an inverter device (2); and positioning pins (5, 6) which are vertically arranged on one of the terminal blocks (3, 4) to position the configuration of the busbar (P, N). Insertion holes (P1, N1) for inserting the positioning pins (5, 6) are formed on the busbar (P, N). The insertion holes (P1, N1) are arranged on the busbar (P, N) at any position in an area (a1, a2) on one end side of the busbar (P, N) that is farther than the distance from the second fastening hole (P3, N3) to the first fastening hole (P2, N2).

Description

Technical Field

[0001] The invention relates to a positioning structure for a busbar applied to electrical equipment such as an inverter device. Background Art

[0002] In the inverter device, the DC capacitor and the switching element are mostly connected through a low-inductance and low-impedance busbar. As the above-mentioned busbar, for example, a busbar for surge suppression applied to the rotary machine drive device of Patent Document 1 can be cited. According to this busbar, it is possible to suppress overvoltage damage caused by the surge voltage reduction during the switching operation of the switching element, and it is possible to obtain the effects of reducing power loss due to the low impedance of the busbar, saving space and reducing costs.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2016-140210 Summary of the invention

[0006] Since conventional busbars do not have positioning pins, it takes time and effort to perform screw tightening with good positional accuracy. Therefore, if positioning pins are provided on the busbars, the creepage distances of the different busbars for preventing discharge can be quickly and accurately ensured.

[0007] However, in order to fix to the bus bar by the positioning pins, it is necessary to ensure a through hole for the positioning pins in the bus bar.

[0008] If the through hole is formed in the bus bar, the inductance and impedance of the bus bar increase, and there is a possibility that a surge voltage during the switching operation of the switching element cannot be reduced, and further, the power loss of the bus bar cannot be reduced.

[0009] The present invention has been made in view of the above circumstances, and an object of the present invention is to improve the assemblability of a bus bar and to reduce inductance and impedance.

[0010] Therefore, one embodiment of the present invention is a busbar positioning structure, comprising: a pair of terminal blocks, the pair of terminal blocks are configured with a busbar connecting two electrical components of an electrical device; and a positioning pin, the positioning pin is vertically arranged on one of the terminal blocks, and positions the configuration of the busbar, an insertion hole is formed on the busbar, the insertion hole is for the positioning pin to be inserted, and the busbar has: a first fastening hole, the first fastening hole is for inserting a fastener that fastens the busbar to the terminal of the electrical component on one side; and a second fastening hole, the second fastening hole is for inserting a fastener that fastens the busbar to the terminal of the electrical component on the other side, and the insertion hole is arranged on the busbar at a position on one end side of the busbar that is farther than the distance from the first fastening hole to the second fastening hole.

[0011] According to one aspect of the present invention, in the busbar positioning structure, a diameter of the insertion hole is smaller than diameters of the first fastening hole and the second fastening hole.

[0012] According to one aspect of the present invention, in the busbar positioning structure, the positioning pin inserted into the insertion hole does not protrude from the insertion hole.

[0013] According to one aspect of the present invention, in the busbar positioning structure, the electrical device is an inverter device, one of the electrical components is a DC capacitor of the inverter device, and the other electrical component is a power module of the inverter device.

[0014] One embodiment of the present invention is an electric device having the above-mentioned busbar positioning structure.

[0015] According to the present invention described above, it is possible to improve the assemblability of the bus bar and reduce the inductance and impedance. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a plan view of a busbar positioning structure according to one embodiment of the present invention applied to an electric device.

[0017] Figure 2 is Figure 1 A top view of the busbar with the wiring harness connected.

[0018] Figure 3 yes Figure 2 A longitudinal sectional view of the state.

[0019] Figure 4 is with Figure 1 Basic circuit diagram of a busbar-connected power module. DETAILED DESCRIPTION

[0020] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0021] Figure 1 The busbar positioning structure 1 according to one embodiment of the present invention shown is applied to terminal blocks 3 and 4 in a housing 10 of an inverter device 2 as an example of electric equipment.

[0022] The busbar positioning structure 1 includes a pair of terminal blocks 3 on which busbars P are arranged, a pair of terminal blocks 4 on which busbars N are arranged, and positioning pins 5 and 6 for positioning the busbars P and N on the terminal blocks 3 and 4 .

[0023] (Bus P)

[0024] like Figure 2As shown, the busbar P connects the connection terminal 71 of the harness 7 to the connection terminal C1 on the P-pole side of the DC capacitor C, which is one of the electrical components of the inverter device 2. In addition, the harness 7 is connected to the P-pole side terminal of the power module 11, which is one of the electrical components. Figure 4 The circuit of switching elements S1 to S6 is shown.

[0025] The busbar P is provided with: an insertion hole P1 for inserting a positioning pin 5 of a terminal block 3 described later, a first fastening hole P2 for inserting a fastener 9 for fastening the connection terminal 71 and the P-pole side terminal of the power module 11 to the busbar P; and a second fastening hole P3 for inserting the fastener 9 for fastening the connection terminal C1 to the busbar P.

[0026] The insertion hole P1 is arranged on the busbar P in the figure at an arbitrary position in the area a1 on one end side of the busbar P which is farther from the connection portion (second fastening hole P3) connected to the connection terminal C1 of the DC capacitor C and the connection portion (first fastening hole P2) connected to the connection terminal 71 of the wiring harness 7. The diameter of the insertion hole P1 is set to be smaller than the diameters of the first fastening hole P2 and the second fastening hole P3. In addition, the insertion hole P1 may be a through hole as long as it is within the range where the inserted positioning pin 5 does not protrude.

[0027] (Bus N)

[0028] The bus bar N connects the connection terminal 81 of the harness 8 connected to the N-pole terminal of the power module 11 and the connection terminal C2 on the N-pole side of the DC capacitor C.

[0029] The bus bar N is provided with: an insertion hole N1 for inserting a positioning pin 6 of a terminal block 4 described later, a first fastening hole N2 for inserting a fastener 9 for fastening the connection terminal 81 and the N-pole side terminal of the power module 11 to the bus bar N, and a second fastening hole N3 for inserting the fastener 9 for fastening the connection terminal C2 to the bus bar N.

[0030] The insertion hole N1 is arranged on the busbar N in the figure at an arbitrary position in the area a2 on one end side of the busbar N which is farther from the connection portion (second fastening hole N3) connected to the connection terminal C2 of the DC capacitor C and the connection portion (first fastening hole N2) connected to the connection terminal 81 of the wiring harness 8. The diameter of the insertion hole N1 is set to be smaller than the diameters of the first fastening hole N2 and the second fastening hole N3. The insertion hole N1 can also be a through hole as long as it is within the range where the inserted positioning pin 6 does not protrude, similarly to the insertion hole P1.

[0031] (Terminal block 3)

[0032] A pair of terminal blocks 3 Figure 3The terminal block 3 shown on one side has a terminal portion 31, which is connected to the connection terminal 71 of the P-pole side harness 7 introduced into the frame 10 and the P-pole side terminal of the power module 11. The terminal portion 31 is formed with a fastening hole 310 for screwing the fastener 9 inserted into the first fastening hole P2 of the busbar P.

[0033] The other terminal block 3 of the pair of terminal blocks 3 includes a terminal portion 32 connected to the connection terminal C1 of the DC capacitor C disposed in the housing 10. The terminal portion 32 has a fastening hole 320 for screwing a fastener 9 that connects the connection terminal C1 to the terminal portion 32 via the bus bar P.

[0034] (Terminal block 4)

[0035] One of the pair of terminal blocks 4 is arranged in parallel with the terminal block 3 and includes a terminal portion 41, which is connected to the connection terminal 81 of the N-pole side harness 8 introduced into the frame 10 and the N-pole side terminal of the power module 11. The terminal portion 41 is formed with a fastening hole 410 for screwing the fastener 9 inserted into the first fastening hole N2 of the bus bar N.

[0036] The other terminal block 4 of the pair of terminal blocks 4 is arranged in parallel with the other terminal block 3 and includes a terminal portion 42 connected to the connection terminal C2 of the DC capacitor C. The terminal portion 42 has a fastening hole 420 formed therein for screwing a fastener 9 that connects the connection terminal C2 to the terminal portion 42 via the bus bar N.

[0037] (Location pins 5, 6)

[0038] The positioning pin 5 is provided upright on the one terminal block 3 at a position corresponding to the insertion hole P1 of the bus bar P. The height of the positioning pin 5 and the thickness of the bus bar P are set so that the positioning pin 5 does not protrude from the insertion hole P1 of the bus bar P.

[0039] The positioning pin 6 is provided upright on the one terminal block 4 at a position corresponding to the insertion hole N1 of the bus bar N. The height of the positioning pin 6 and the thickness of the bus bar N are set so that the positioning pin 6 does not protrude from the insertion hole N1 of the bus bar N.

[0040] (Assembly Procedure of Inverter Device 2)

[0041] Reference Figures 1 to 3 An example of the assembly procedure of the inverter device 2 will be described.

[0042] First, a busbar P is arranged on a pair of terminal blocks 3 in the frame 10. Figure 1 , 3As shown, the insertion hole P1 and the first fastening hole P2 of the busbar P respectively meet with the positioning pin 5 and the fastening hole 310 of the terminal block 3 on one side, and one end side of the busbar P is arranged at the terminal portion 31 of the terminal block 3 on the one side. At this time, the second fastening hole P3 of the busbar P meets with the fastening hole 320 of the terminal block 3 on the other side, and the other end side of the busbar P is arranged at the terminal portion 32 of the terminal block 3.

[0043] Next, a bus bar N is arranged on a pair of terminal blocks 4 in the frame 10. Figure 1 As shown, the insertion hole N1 and the first fastening hole N2 of the busbar N meet with the positioning pin 6 and the fastening hole 410 of the terminal block 4 on one side, respectively, and one end side of the busbar N is arranged at the terminal portion 41 of the terminal block 4 on the one side. At this time, the second fastening hole N3 of the busbar N meets with the fastening hole 420 of the terminal block 4 on the other side, and the other end side of the busbar P is arranged at the terminal portion 42 of the terminal block 4.

[0044] Next, the connection terminals 71, 81 of the harnesses 7, 8 introduced into the housing 10 are disposed at the terminal portions 31, 41 of the terminal blocks 3, 4. The connection terminals C1, C2 of the DC capacitor C are disposed at the terminal portions 32, 42 of the terminal blocks 3, 4.

[0045] Moreover, if Figure 2 , 3 As shown, the fastener 9 inserted through the connection terminal 71 of the wiring harness 7 and the first fastening hole P2 of the busbar P is screwed into the fastening hole 310 of the terminal portion 31 of the terminal block 3 on one side. In addition, the fastener 9 inserted through the connection terminal C1 of the DC capacitor C and the second fastening hole P3 of the busbar P is screwed into the fastening hole 320 of the terminal portion 32 of the terminal block 3 on the other side.

[0046] Similarly, the fastener 9 inserted through the connection terminal 81 of the wiring harness 8 and the first fastening hole N2 of the busbar N is screwed into the fastening hole 410 of the terminal portion 41 of the terminal block 4. In addition, the fastener 9 inserted through the connection terminal C2 of the DC capacitor C and the second fastening hole N3 of the busbar N is screwed into the fastening hole 420 of the terminal portion 42 of the terminal block 4 on the other side.

[0047] As mentioned above, in Figure 2 The busbars P and N are connected and fixed to the terminal blocks 3 and 4 in the frame 10.

[0048] (Effects of this embodiment)

[0049] exist Figure 2In the busbars P and N of the inverter device 2 shown, the path of the white arrow connecting the first fastening hole P2 and the second fastening hole P3 at the shortest distance, and the path of the white arrow connecting the first fastening hole N2 and the second fastening hole N3 at the shortest distance correspond to the current path of the inverter device 2, and the current density is the highest. On the other hand, in the areas a1 and a2 on the one end side of the busbars P and N that are farther than the distance from the second fastening hole P3 and N3 to the first fastening hole P2 and N2, the current density becomes low.

[0050] According to the busbar positioning structure 1, by forming the insertion holes P1 and N1 for inserting the positioning pins 5 and 6 of the terminal blocks 3 and 4 at arbitrary positions in the areas a1 and a2, it is possible to reduce the increase in the inductance and impedance of the busbars P and N. In particular, by setting the diameter of the insertion holes P1 and N1 to be smaller than the diameter of the first fastening holes P2 and N2 and the second fastening holes P3 and N3, it is possible to further reduce the increase in the inductance and impedance of the busbars P and N.

[0051] In addition, if Figure 3 As shown, by adjusting the thickness of the busbars P, N or the height of the positioning pins 5, 6 so that the positioning pins 5, 6 do not protrude from the insertion holes P1, N1, the above-mentioned basic circuit and other electrical components other than the DC capacitor C can be arranged on the positioning pins 5, 6, so there is no need to expand the busbar more than necessary.

[0052] As described above, according to the busbar positioning structure 1, by setting the positioning pins 5, 6 and the insertion holes P1, N1 at positions that minimize the increase in the inductance and impedance of the busbar, the busbars P, N can be easily assembled while ensuring the creepage distance for preventing discharge.

[0053] In particular, by arranging the insertion holes P1 and N1 at positions closer to the end side of the busbars P and N than the line connecting the through holes of the connection screw terminal portion by the shortest path, the assembly of the busbars P and N is improved. In addition, the increase in inductance, impedance, loss, and heat generation of the busbars P and N can be suppressed. In addition, the surge voltage of the switching element caused by the low inductance of the busbars P and N is reduced. In addition, the power efficiency of the inverter device 2 caused by the low impedance of the busbars P and N is improved.

[0054] In addition, the busbar positioning structure of the present invention can also be applied to electrical equipment other than inverter devices using busbars. For example, in a general busbar that connects electrical components other than DC capacitors C and switching elements, by providing holes for inserting positioning pins, the increase in inductance and impedance can be reduced, as with busbars P and N. Therefore, in a general busbar, by providing holes for inserting positioning pins at a position closer to the end of the busbar than the line of the shortest path of the current, it becomes easier to assemble the creepage distance to prevent discharge, which can reduce the increase in impedance and achieve the effect of reducing power loss.

Claims

1. A busbar positioning structure, wherein: The busbar positioning structure has: a pair of terminal blocks provided with bus bars for connecting two electrical components of the electrical device; and A positioning pin is vertically arranged on one of the terminal blocks to position the busbar. On the busbar are formed: An insertion hole, wherein the positioning pin is inserted into the insertion hole; a first fastening hole through which a fastener for fastening the busbar to a terminal of one of the electrical components is inserted; as well as a second fastening hole through which a fastener for fastening the busbar to a terminal of the other electrical component is inserted; The electrical device is an inverter device, The electrical component on one side is a DC capacitor of the inverter device, The other electrical component is a power module of the inverter device, The insertion hole is arranged on the bus bar at a position in a region where current density is lower than the shortest path between the first fastening hole and the second fastening hole. The region where the current density is low is a region on the bus bar on one end side of the bus bar that is farther than the distance from the second fastening hole to the first fastening hole.

2. The busbar positioning structure according to claim 1, wherein: The insertion hole has a smaller diameter than the first fastening hole and the second fastening hole.

3. The busbar positioning structure according to claim 1 or 2, wherein: The positioning pin inserted into the insertion hole does not protrude from the insertion hole.

4. An electrical device, wherein: The electrical equipment has the busbar positioning structure according to claim 1.

Images