Classifications

• • H—ELECTRICITY
  • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
  • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
  • H05K7/00—Constructional details common to different types of electric apparatus
  • H05K7/14—Mounting supporting structure in casing or on frame or rack
  • H05K7/1422—Printed circuit boards receptacles, e.g. stacked structures, electronic circuit modules or box like frames
  • H05K7/1427—Housings
  • H05K7/1432—Housings specially adapted for power drive units or power converters
  • H05K7/14329—Housings specially adapted for power drive units or power converters specially adapted for the configuration of power bus bars

Definitions

• the present invention relates to a switching cell, in particular for a mobility device comprising an inverter associated with an electrical machine.
• a switching cell comprising: power modules is known from the state of the art; and a first bus bar, called the upper bus bar, and a second bus bar, called the lower bus bar, connected to each of the power modules in order to distribute a direct voltage to the latter; and at least one capacitor with two terminals respectively soldered to the two bus bars.
• a switching cell comprising: power modules; a first bus bar, called the upper bus bar and a second bus bar, called the lower bus bar, connected to each of the power modules in order to distribute a direct voltage to the latter, the upper bus bar and the lower bus bar each comprising a first plate ; and, at least one capacitor with two terminals respectively soldered to the first and the second bus bar; characterized in that it comprises a support for the upper and lower bus bar having a fixing pin, in that the first plate of the bar upper bus has an opening for receiving the fixing pin, the latter being bolted to fix the first plate of the upper bus bar to the support.
• the invention may also include one or more of the following optional characteristics, according to any technically possible combination.
• the two terminals of the capacitor are respectively soldered to the first plate of the first bus bar and to the first plate of the second bus bar.
• the support of the upper and lower bus bar have fixing pins and the first plate of the upper bus bar has openings for receiving the fixing pins, the latter being doweled to fix the first plate. the upper bus bar to the bracket.
• each fixing pin is received respectively in a different reception opening.
• the first plate of the upper bus bar and the first plate of the lower bus bar are flat.
• the upper bus bar and the lower bus bar are stacked on top of each other and the first plate of the lower bus bar is held between the first plate of the upper bus bar and the support.
• the lower bus bar is designed to present a high electrical potential and the upper bus bar is designed to present a low electrical potential.
• the support comprises a bottom on which the first plates of the stacked bus bars extend, in which the first plate of the lower bus bar has an opening leaving visible a part, called connection part, of the first plate of the upper bus bar and in which the bottom has an opening leaving visible a part, called the connection, of the first plate of the lower bus bar and at least part of the opening of the first plate of the lower bus bar, in order to connect, on the one hand, a first terminal of the capacitor to the connection part of the lower bus bar through the bottom opening and, on the other hand, a second terminal of the capacitor to the connection part of the upper bus bar through the bottom opening and the bar opening lower omnibus.
• connection part of the first plate of the lower bus bar has a reduced thickness compared to the rest of the first plate of the lower bus bar.
• the first plate of the upper bus bar has a boss extending into the opening of the first plate of the lower bus bar.
• the boss has a flat lower connection wall having a reduced thickness compared to the rest of the first plate of the upper bus bar.
• the support has a positioning pin for the first plate of the lower bus bar.
• the positioning pin is arranged so as to hold the first plate of the lower bus bar in place perpendicular to the fixing pin.
• the positioning pin extends parallel to the fixing pin.
• the positioning pin enters an opening in the first plate of the lower bus bar and allows the lower bus bar to be held in place.
• the support has positioning pins for the first plate of the lower bus bar.
• the positioning pins are arranged so as to hold the first plate of the lower bus bar in place perpendicular to the fixing pins. [0024] Optionally, the positioning pins extend parallel to the fixing pins.
• each positioning pin enters a respective opening in the first plate of the lower bus bar and allows the lower bus bar to be held in place.
• each power module implements a switching arm designed to carry out a conversion between the direct voltage and an alternating voltage.
• the switching cell further comprises a cooling circuit for the power modules, said cooling circuit comprising a cooling housing defining a flow channel for a cooling liquid, the cooling housing having an upper cooling face and a lower cooling face, both cooled by the flow of the cooling liquid in the channel, the power modules being pressed against the upper cooling face to be cooled.
• the first plate of the upper bus bar is in thermal contact with the lower cooling face.
• the cooling casing further comprises a coolant inlet conduit into the cooling casing and a coolant outlet conduit from the cooling casing, the inlet conduit and the outlet conduit each having a segment, the segment of the inlet conduit and the segment of the outlet conduit projecting substantially parallel to one another in the same direction.
• a first insulating layer is inserted between the first plates of the upper and lower bus bars.
• a second insulating layer is positioned between the top of the first plate of the upper bus bar and the lower face of the cooling housing.
• an inverter comprising a switching cell according to the first aspect of the invention.
• the inverter further comprises a housing in the interior of which the switching cell is positioned, the housing having two passage openings, the segment of the input conduit being inserted in one of the two openings of passage and the segment of the outlet conduit being inserted into the other of the two passage openings.
• a mobility device comprising a switching cell according to the first aspect of the invention or an inverter according to the second aspect of the invention.
• a mobility device is for example a motorized land vehicle, a train, an aircraft or a drone.
• a motorized land vehicle is for example a motor vehicle, a motorcycle, a motorized bicycle or a motorized wheelchair.
• Figure 1 is a sectional view of an example of a switching cell in which the invention is implemented
• Figure 2 is a three-dimensional view of the switching cell
• Figure 3 is a three-dimensional view of the switching cell, with a map of control, a cover and a spring system removed
• Figure 4 is a three-dimensional view of a capacitor of the switching cell
• Figure 5 is a block diagram of a method of manufacturing the capacitor
• Figure 6 is a three-dimensional and sectional view of bus bars and a support of the bus bars of the switching cell
• Figure 7 is a three-dimensional view of the bus bars, their support and capacitors of the switching cell , where fixing pins are visible, before their bolting
• Figure 8 is a view similar to Figure 7, after bolting the fixing pins
• Figure 9 is a three-dimensional view of the underside of the bus bar support
• Figure 10 is a three-dimensional view in section of the
• the switching cell 100 firstly comprises several power modules 102.
• three power modules 102 are provided.
• the power modules 102 are for example placed next to each other.
• the switching cell 100 further comprises an electronic card 104 for controlling the power modules 102.
• the electronic control card 104 extends for example above the power modules 102.
• the switching cell 100 further comprises a circuit 106 for cooling the power modules 102.
• the cooling circuit 106 comprises a cooling housing 108 defining a channel 110 for the flow of the cooling liquid.
• the cooling box 108 has an upper cooling face 112 and a lower cooling face 113, both cooled by the flow of the cooling liquid in the channel 110.
• the power modules 102 are thus pressed against the upper face of cooling 112 to be cooled.
• the switching cell 100 comprises for example first of all a cover 114 extending above the power modules 102, for example between the electronic control card 104 and the power modules 102.
• the cover 114 is fixed to the cooling box 108, for example by screws.
• the switching cell 100 further comprises a spring system interposed between the cover 114 and the power modules 102. This spring system is thus designed to rest on the cover 114 and push the power modules 102 towards the upper face of the cooling 112.
• the spring system comprises for example, for each power module 102, a flexible blade 116, compressed between the cover 114 and the power module 102.
• the cooling circuit 106 further comprises a conduit 118 for entering the cooling liquid into the cooling housing 108 and a conduit 120 for exiting the cooling liquid from the cooling housing 108.
• the conduits 118, 120 are for example located respectively to the right and left of the cooling box 108 and project vertically towards the bottom of the latter.
• the switching cell 100 further comprises a so-called positive bus bar 128 and a so-called negative bus bar 130, stacked one on top of the other.
• One of the two bus bars 128, 130 thus forms a lower bus bar, while the other forms an upper bus bar.
• the so-called positive bus bar 130 and the so-called negative bus bar 128 each comprise a first plate and a second plate, the first plate being in material continuity with the second plate.
• the first plate of each of the two bus bars is a flat plate.
• the first plate of the positive bus bar 128 extends under the first plate of the negative bus bar 130 and the first plate of the negative bus bar 130 extends under the cooling housing 108.
• the positive bus bar 128 forms the lower bus bar and the negative bus bar 130 forms the upper bus bar.
• the reverse configuration is also possible.
• the second plate of the positive bus bar 128 and the second plate of the negative bus bar 130 extend along one side of the cooling housing 108.
• the positive bus bar 128 is designed to present a high electrical potential, while the negative bus bar 130 is designed to present a low electrical potential, lower than the high electrical potential, so that the bus bars 128, 130 are designed to present, between them, a direct voltage UDC-
• the switching cell 100 comprises for example a support 132, in particular made of electrical insulating material, for example plastic. More precisely, the support 132 has a bottom 134 on which the first plates of the bus bars 128, 130 extend.
• the support 132 is fixed to the cooling housing 108 so that the first plates of the bus bars 128, 130 extend between the lower cooling face 113 of the cooling housing 108 and the bottom 134 of the support 132. The bus bars 128, 130 can thus be cooled through the lower cooling face 113.
• the switching cell 100 further comprises capacitors 136 each comprising two terminals 138, 140 respectively connected to the bus bars 128, 130 to receive the direct voltage UDC. These capacitors 136 are designed to smooth the direct voltage UDC and are generally called in English “DC link capacitor”.
• the capacitors 136 are for example placed under the bus bars 128, 130 and in particular under the bottom 134 of the support 132, their terminals 138, 140 passing through the bottom 134 of the support to reach the bus bars 128, 130, like this will be described in more detail later.
• each power module 102 is for example designed to carry out a transformation between the direct voltage UDC and a respective alternating voltage, for example phase voltages of an electrical machine.
• Each power module 102 thus has an external connector 202 designed to present this alternating voltage.
• the external connector 202 is for example in the form of a flat bar, preferably having a thickness of at least 0.8 mm.
• the switching cell 100 further comprises, around each external connector 202, a magnetic core 204 of a current sensor.
• the magnetic core 204 is looped and has an air gap in which a Hall effect sensor can for example be placed for current measurement.
• each power module 102 comprises, in addition to the alternative external connector 202, a so-called positive external connector 302 and a so-called negative external connector 304, designed to be connected respectively to the positive bus bar 128 and to the negative bus bar 130.
• These external connectors 302, 304 are for example in the form of flat bars, preferably having a thickness of at least 0.8 mm. In the example illustrated, two negative external connectors 304 are provided for each power module 102.
• each power module 102 implements for example a switching arm and thus comprises, in a housing 305, two switches 306, 308 connected to each other at a midpoint, -even connected to the external alternating connector 202 to present the alternating voltage.
• the switching arm is connected between the external connectors 302, 304 to present the direct voltage UDC.
• These switches 306, 308 are illustrated in Figure 3 schematically for only one of the power modules 102, and not on the others for reasons of concern. clarity.
• Each switch 306, 308 is preferably a controllable semiconductor switch, for example a transistor switch such as a metal-oxide gate field effect transistor (from the English “Metal Oxide Semiconductor Field”). Effect Transistor” also referred to by the acronym MOSFET) or an insulated gate bipolar transistor (from the English “Insulated Gate Bipolar Transistor” also referred to by the acronym IGBT) or a gallium nitride field effect transistor (from the English “Gallium Nitride Field Effect Transistor” also designated by the acronym GaN FET).
• a transistor switch such as a metal-oxide gate field effect transistor (from the English “Metal Oxide Semiconductor Field”). Effect Transistor” also referred to by the acronym MOSFET) or an insulated gate bipolar transistor (from the English “Insulated Gate Bipolar Transistor” also referred to by the acronym IGBT) or a gallium nitride field effect transistor (from the English “Gallium Nitride Field Effect Transistor
• Each power module 102 also has control pins 312, allowing in particular the control card 104 to control the switching of the switches 306, 308. These control pins 312 are bent so as to present a horizontal segment emerging from the housing 305 of the power module 102 and a vertical segment rising upwards to reach the control card 104.
• each capacitor 136 comprises a main body 402, each terminal 138, 140 comprising an internal part 404 in the main body 402, and an external part 406 outside the main body 402, projecting from the latter.
• the main body 402 comprises for example a capacitive device 408 and an overmolding 410 covering the capacitive device 408.
• the capacitive device 408 is the part of the capacitor 136 where the electrical energy is stored.
• the overmolding 410 is for example made of resin.
• the internal part 404 of each terminal 138, 140 thus extends for example into the overmolding 410 to join the capacitive device 408.
• the external part 406 of each of the terminals 138, 140 firstly has a support portion 412.
• the support portion 412 extends for example in continuity with the internal part 404.
• the support portion 412 is for example plane.
• connection portion 414 designed to be welded to a respective one of the bus bars 128, 130, as will be described in more detail later.
• the connection portion 414 is attached to the support portion 412 by a fold and extends at a distance from the main body 402.
• the connection portion 414 has an upper face intended to be pressed against the associated bus bar 128, 130, in order to to be welded there for example by laser welding.
• the external part 406 of each of the terminals 138, 140 also has a protective portion 416 attached to the portion of connection 414 by a fold so as to be folded between the connection portion 414 and the main body 402.
• the fold between the connection portion 414 and the protective portion 416 is opposite the fold between the support portion 412 and the connection portion 414
• each of the terminals 138, 140 further comprises for example at least one auxiliary support portion 418 attached to the connection portion 414 by a fold, so as to project towards the main body 402, by example vertically downwards as in the example shown.
• the auxiliary support portion 418 has, opposite the connection portion 414, one end in contact with the main body 402, for example extending into the latter. For example, this end is taken in the overmolding 410, as in the example illustrated.
• the end preferably has a hook 420, that is to say a protrusion.
• This excrescence is covered by the overmolding 410 in the direction of projection of the auxiliary support portion 418, that is to say vertically in the example illustrated.
• This hook 420 limits the risk of the auxiliary support portion 418 being torn from the overmolding 410 and the risk of deformation of the connection portion 414, when the auxiliary support portion 418 is pulled parallel to the direction of projection.
• connection portion 414 is carried by the support portion 412 and, where appropriate, by the auxiliary support portion(s) 418.
• each terminal 138, 140, or at least its external part 406, is formed from a single folded flat plate.
• each terminal 138, 140 obtained is flat, for example cut from a plate.
• the external part 406 and the internal part 404 are coplanar, in continuity with each other.
• the external part 406 is in particular folded between the protection portion 416 and the connection portion 414, to bring the protection portion 416 under the connection portion 414.
• Other foldings of the external part 406 of the terminal 138, 140 can also be made during step 604, for example to give it the shape illustrated in Figure 4.
• the auxiliary support portion(s) 418 can be folded relative to the connection portion 414.
• the entire internal part 404 and the support portion 412 can be folded relative to the connection portion 414. to the connection portion 414.
• the internal parts 404 of the terminals 138, 140 are fixed to the capacitive device 408.
• the protection portion 416 extends between the connection portion 414 and the main body 402, which is devoid of overmolding 410.
• the overmolding 410 is formed around the capacitive device 408, the internal part 404 of the terminal 138, 140 and the hooks 420 if they are provided.
• an insulating layer 502 is for example provided above the first plate of the upper bus bar 130, to insulate it from the cooling housing 108.
• an insulating layer 504 is interposed between bus bars 128, 130.
• the support 132 has fixing pins 702 respectively received in openings made in the first plate of the upper bus bar 130.
• the fixing pins 702 project for example upwards from the bottom 134 of support 132.
• the support 132 also has, for example, pins 704 for positioning the lower bus bar 128.
• Each positioning pin 704 enters a respective opening in the first plate of the lower bus bar 128 and makes it possible to hold the lower bus bar 128.
• the positioning pins 704 are arranged so as to hold the first plate of the lower bus bar 128 in place perpendicular to the fixing pins 702.
• the positioning pins 704 extend parallel to the fixing pins 702, that is to say upwards.
• the fixing pins 702 are each doweled, to fix the first plate of the upper bus bar 130 to the support 132. In doing so, the lower bus bar 128 is held in place since its first plate is sandwiched between the first plate of the upper bus bar 130 and the bottom 134 of the support 132.
• the bolting consists of deforming, for example hot, the end of each positioning pin 704 to form a stop for the first plate of the upper bus bar 130.
• the first plate of the lower bus bar 128 has, for each capacitor 136, an opening 902 (for example, a window or an indentation) leaving a part 904 of the first plate visible.
• This part 904 is designed to be connected to one of the terminals 138, 140 of the capacitor 136 and will hereinafter be called "connection part 904".
• connection part 904 of the upper bus bar 130 has for example a boss 906 extending into the opening 902 of the first plate of the lower bus bar 128.
• the bottom 134 of the support 132 has an opening 908 (for example, a window or a notch) leaving a part 910 of the first plate of the lower bus bar 128 visible.
• This part 910 is designed to be connected to the other of the terminals 138,140 of the capacitor 136 and will hereinafter be called "connection part 910".
• the connection part 910 of the first plate of the lower bus bar 128 has a reduced thickness compared to the rest of the first plate of the lower bus bar 128, for example reduced by at least 25%.
• connection part 910 has a thickness of at most 0.6 mm, while the first plate of the lower bus bar 128 has, around the connection part 910, a thickness of at least 1 mm. This reduced thickness makes it easier to weld terminal 138, 140 of capacitor 136.
• the opening 908 of the bottom 134 also leaves visible the opening 902 of the first plate of the lower bus bar 128.
• the connection part 904 of the first plate of the upper bus bar 130, and in particular the boss 906, is visible through the opening 908 of the bottom 134 and the opening 902 of the first plate of the lower bus bar 128.
• the boss 906 has for example a flat lower connection wall 912.
• this connection wall 912 has a reduced thickness compared to the rest of the first plate of the upper bus bar 130, for example reduced by at least minus 25%.
• the connection wall 912 has a thickness of at most 0.6 mm, while the first plate of the lower bus bar 128 has, around the boss 906, a thickness of at least 1 mm. This reduced thickness makes it easier to weld terminal 138, 140 of capacitor 136.
• the first plate of the upper bus bar 130 has, for each connection part 910 of the first plate of the lower bus bar 128, an opening (for example, a window or an indentation) leaving visible the connection part 910.
• one of the terminals (the negative terminal 140 in the example illustrated) is connected, for example by welding, to the connection part 904 of the upper bus bar 130, and more particularly to the connection wall 912 of the boss 906.
• the other of the terminals (the positive terminal 138 in the example illustrated) is connected, for example by welding, to the connection part 910 of the lower bus bar 128.
• the terminals 138, 140 of the capacitor 136 are respectively pressed against the bus bars 128, 130.
• the connection portions 414 of the terminals 138, 140 are respectively pressed against the wall of connection 912 of the boss 906 of the upper bus bar 130 and against the connection part 910 of the lower bus bar 128.
• the plating is plane on plane, for example on a plate of at least 20 mm 2 .
• a laser beam is sent onto the bus bar 128, 130, at opposite the plated terminal 138, 140.
• the laser beam 1202 is sent by a laser 1204 in a direction 1206 passing successively through the bus bar 128, 130, the connection portion 414 of the plated terminal 138, 140, the portion of protection 416 of the plated terminal 138, 140 and the main body 402 of the capacitor 136.
• the direction 1206 is thus perpendicular to the connection portion 414.
• connection part 910 of the first plate of the lower bus bar 128 allows the laser beam to directly reach the connection part 910 of the first plate of the lower bus bar 128 to be able to weld this connection part 910 to the terminal of the capacitor 136 against which it is pressed.
• the positioning notch 1302 has two walls 1304, 1306 making between them an angle of between 80° and 100°, preferably between 90° and 95°, more preferably 90°, so as to correctly position the control pin 312.
• the control pin 312 thus has an end segment 1308 terminated by a tip 1310.
• the control pin 312 is designed to be inserted into a respective receiving hole of the electronic card 104 by its tip 1310.
• This end segment 1308 is for example straight (vertical in the example illustrated) and has a positioning part 1312 having a length of at least 5 mm and extending over its entire length to at most 0, 5 mm from each of the walls 1304, 1306 of the positioning notch 1302.
• control pin 312 illustrated in Figure 13 is thus, for example, designed to be inserted freely (not by force) into the receiving hole, then soldered to the electronic card 104.
• control pin 312 is for example designed to be inserted by force into the receiving hole of the electronic card 104.
• the end segment 1308 has a force insertion part 1402 having a width greater than the receiving hole of the electronic card.
• the force insertion part 1402 comprises two rods meeting at their ends and separated in the middle by a space.
• the frame 206 has at least one chamfer 1404 for guiding the control pin 312, and more particularly its elbow, towards the positioning notch 1302.
• the chamfer 1404 facilitates insertion, in particularly vertically, of the control pin 312 in the positioning notch 1302.
• the end segment 1308 also has a protrusion 1502 projecting perpendicularly to the vertical direction so as to extend above the support piece in the vertical direction, preferably , less than 0.1 mm from the frame 206 in the vertical direction, preferably in contact with the frame 206.
• This protrusion 1502 is for example located between the force insertion part 1402 and the positioning part 1312.
• a method 1600 for manufacturing the switching cell 100 comprises for example the following steps.
• step 1602 the power module 102 is obtained with the control pins 312 coming out of the housing 305.
• step 1604 the electronic card 104 is obtained, with a hole for receiving each control pin 312.
• the power module 102 is fixed to the cooling box carrying the frame 206. During this fixing, the power module 102 is lowered vertically, so that the control pins 312, in particular guided by the chamfers 1502, enter respectively into the positioning notches 1302.
• step 1608 the electronic card 104 is lowered vertically towards the power modules 102, so that the control pins extending into the positioning notch are inserted respectively into the receiving holes.
• the switching cell 100 is for example designed to form part of an electrical system, for example an inverter 1702.
• the inverter 1702 comprises, for example, an electromagnetic compatibility (EMC) filter 1704 connected between the two bus bars 128, 130 and a box, called the general box 1706, in which the CEM filter 1704 and the switching cell are placed. 100.
• EMC electromagnetic compatibility
• the general housing 1706 comprises for example a main part 1708 having an upper opening 1710 and a cover (not shown) designed to close this upper opening 1710.
• the general housing 1706 further comprises for example a lower opening 1712 for passage of the capacitors 136 and a cover 1714 to close this lower opening 1712.
• the inlet conduit 118 and the outlet conduit 120 respectively have two segments 1716, 1718 projecting substantially parallel to each other in the same direction.
• the general housing 1706 then has two openings 1720, 1722 for respectively passing through the segments 1716, 1718.
• Each opening 1720, 1722 has for example a seal 1724, 1726 intended to cooperate with the inserted segment 1716, 1718.
• the segments 1716, 1718 thus have, outside the general housing 1706, respective ends 1728, 1730 designed to be connected to a cooling liquid circulation system. These ends 1728, 1730 can for example have entry chamfers.
• the connection of the cooling circuit is made outside the general housing 1706, so as to reduce the risk of leaks in the general housing in the event of poor sealing of this connection.
• the switching cell 100 is inserted through the upper opening 1710 into the general housing 1706.
• the segments 1716, 1718 of the conduits 118, 120 are inserted respectively into the openings 1720, 1722 provided in the main part 1708 to guide the positioning of the switching cell 100 inside the main housing 1706.
• the switching cell 100 is fixed to the main part 1708 of the general housing 1706, for example by screwing.

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• Engineering & Computer Science (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Inverter Devices (AREA)
• Power Conversion In General (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=83438242

Family Applications (1)

Country Status (4)

Family Cites Families (2)

• 2022
  • 2022-06-30 FR FR2206657A patent/FR3137531A1/fr active Pending
• 2023
  • 2023-06-29 CN CN202380051076.4A patent/CN119452745A/zh active Pending
  • 2023-06-29 EP EP23737957.3A patent/EP4548718A1/de active Pending
  • 2023-06-29 WO PCT/EP2023/067940 patent/WO2024003324A1/fr not_active Ceased

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