A BUS BAR ASSEMBLY OF A POWER CONVERTER - BUS BAR ASSEMBLY OF A POWER CONVERTER - SCOPE OF THE INVENTION

Abstract

POWER CONVERTER BUS BLOCK ASSEMBLY This topic concerns a bus bar assembly. More specifically, this topic concerns a power converter 100 which includes an inverter, a step-up converter, and a bus bar assembly 104. The inverter has an inverter circuit adapted for converting direct current (DC) to alternating current (AC), the inverter being contained in a housing. The step-up converter contained in the housing has a step-up converter circuit adapted for stepping up the voltage from a low voltage level to a high voltage level. The bus bar assembly (104) includes three bus bars (106; 108; 110) which pass through a single electromagnetic compatibility (EMC) filter (112).The three busbars (106; 108; 110) comprise a positive busbar (106), a negative busbar (108), and a boost busbar (110), all arranged inside the housing and adapted to carry the positive DC power supply, the negative DC power supply, and the boost converter circuit output, respectively. Figure for abbreviation: FIG. 3A.

Description

Title of the invention: ASSEMBLY OF OMNIBUS BARS OF A POWER CONVERTER SCOPE OF THE INVENTION

[0001] The present subject relates to a busbar assembly of a power converter. The busbar assembly described herein is preferably applicable to automotive applications.

[0002] CONTEXT

[0003] Electric vehicles (EVs) are becoming increasingly popular due to their environmental benefits and advances in battery technology. In EVs, an inverter and a boost converter are commonly used to control the speed and torque of the electric motor, as well as to manage the flow of power in the vehicle's electrical system. The inverter converts direct current (DC) to alternating current (AC) to power the motor, thereby controlling motor performance, including acceleration, deceleration, and regenerative braking. The boost converter increases the voltage of the main traction battery to a higher level, typically to charge a 12-volt auxiliary battery or to power other low-voltage systems in the vehicle.The motor itself is powered by the inverter, which converts the direct current (DC) from the main battery into alternating current (AC) to drive the motor. In one scenario, the boost converter is used to charge the main battery of an electric vehicle (EV), with one input side connected to an external DC charging source and the output side connected to the main battery. Most current charging stations have a maximum voltage of 750 volts, while EVs, in particular, have a maximum voltage of 870 volts. This means the charging station's voltage must be increased (i.e., the amplification function) to be able to charge the electric vehicle at a higher charging power.

[0004] To facilitate interaction between the motor, the converter, and the boost converter, busbars are used. Busbars are well known in electronic applications for facilitating the flow of electrical energy from one element to another in an electrical circuit. Generally, boost converters, or step-up converters (or DC-DC converters), include a boost busbar for power transmission to facilitate the functions of the boost converter described above. Modern inverters are designed to integrate the boost converter. These inverters include three main busbars: a busbar positive, a negative busbar and an amplification busbar. The positive and negative busbars carry the main DC current from the battery to the inverter, while the auxiliary busbar carries the output of the auxiliary converter, which increases the voltage as needed for various functions, for example to charge auxiliary systems.

[0005] However, the current design of inverters with integrated boost converters may have some drawbacks. For example, the physical arrangement of the busbars in the inverter housing can lead to inefficiencies in power transmission, increased heat generation, and difficulties in assembly and maintenance.

[0006] It is therefore necessary to improve the design of the busbar configuration in the inverter with integrated boost converter. Such a design should optimize power transmission efficiency, minimize heat generation, simplify assembly and maintenance processes, and improve the overall performance and reliability of the inverter system in applications not limited to EVs, but also including plug-in hybrid vehicles.

[0007] Therefore, the technical problem to be solved by this topic is how to provide a power converter (such as an inverter) in which multiple busbars are housed in the casing so as to minimize the casing size. Other improvements to the power converter, such as optimizing power transmission efficiency, minimizing heat generation, simplifying assembly and maintenance processes, and improving the overall performance and reliability of the power converter, are sought. Summary of the invention

[0008] The present subject aims to solve the aforementioned technical problem in conventional power converters, and more particularly in power converters in which a boost converter circuit is incorporated.

[0009] The present subject relates to a power converter comprising: an inverter having an inverter circuit adapted for converting direct current (DC) into alternating current (AC), the inverter being contained in a housing; an auxiliary converter contained in the housing and having an auxiliary converter circuit adapted for stepping up the voltage from a low voltage level to a high voltage level; and a busbar assembly comprising three busbars passed through a single electromagnetic compatibility filter, the three busbars comprising: a positive busbar, a negative busbar, and a busbar of The boost converter circuit is housed within the enclosure to respectively conduct the positive DC power supply, the negative DC power supply, and the output of the boost converter circuit. As a result, the three busbars are positioned close together, reducing the overall size of the enclosure. Furthermore, it is now possible to pass the three busbars through an EMC filter. The internal component layout of the power converter is more efficient.

[0010] The electromagnetic compatibility (EMC) filter is, in one aspect, in the form of a container. The "single" EMC filter referred to here means that there is only one container and that all three busbars pass through the same container. The EMC filter attenuates electromagnetic interference noise and ensures that the three busbars do not emit or conduct excessive interference that could disrupt the performance of other components. Furthermore, the EMC filter prevents errors and malfunctions that can occur due to electromagnetic interference, resulting in a more reliable and stable power supply through the three busbars.

[0011] According to one aspect of the present object, the positive busbar, the negative busbar, and the auxiliary busbar are at least partially covered by an overmolding made of electrically insulating material, the overmolding comprising multiple through holes into which the fasteners are inserted. Consequently, because the three busbars are incorporated into a single part, i.e., the busbar assembly, the assembly of the three busbars is completed in fewer steps during production.

[0012] According to one aspect of the present object, the positive busbar, the negative busbar, and the auxiliary busbar are equally spaced inside the housing. Consequently, regardless of the proximity between the three busbars, their assembly and production with the overmolded part can be facilitated more easily.

[0013] According to another aspect of the present subject, the positive busbar, the negative busbar, and the auxiliary busbar each have multiple curves adapted to accommodate the internal layout requirements within the housing. Consequently, optimized placement of the entire busbar assembly is facilitated inside the housing.

[0014] According to an example in the present subject, the positive busbar, the negative busbar, and the supercharge busbar are each divided into two sections lengthwise, the two sections being: a first section comprising a first free end and an end connected to each end along the length The first section comprises two parts: one with the positive and one with the negative busbar connected to the inverter circuit, and the other with the positive and negative busbar adapted for connection to the stator phases of a rotating machine; and a second section with a second free end and a connector end at each end along its length, the connector end adapted for connection to an electrical power source. Consequently, the three busbars can be easily assembled. For example, the EMC filter is applied to all three busbars, regardless of the multiple bends formed on said busbars.

[0015] According to an example of this object, the first free end and the second free end are joined by brazing or welding. Thus, even if the three busbars are very close to each other, the two sections can be joined easily and without the need for fasteners or fastener tightening tools.

[0016] According to an example in this subject, one of the two sections comprises a straight portion without curves, which passes through the EMC filter. The straight portion allows the three busbars to pass through the EMC filter. The two sections can then be assembled. Assembly is facilitated.

[0017] According to one aspect of the present subject, the overmolded portion further comprises a filter housing in which the electromagnetic compatibility (EMC) filter is housed. The EMC filter is supplied with the filter housing in which the EMC is protected.

[0018] According to an example in this subject, the filter housing includes a snap-fit ​​opening through which a snap-fit ​​ridge, formed on the electromagnetic compatibility (EMC) filter, is inserted. Thus, the EMC filter is held in place within the filter housing. The rigidity of the entire busbar assembly is ensured.

[0019] According to another example in this subject, the overmolded portion further includes housings in which the capacitor modules are housed. The capacitor modules, such as capacitors Cx and Cy, are housed in these enclosures and are thus structurally protected.

[0020] This subject also relates to an electrical system comprising: a rotating machine; an electrical power source; and a power converter, configured in accordance with one of the preceding descriptions.

[0021] The present subject has a particularly advantageous application in automotive applications where the rotating machine provides traction to an electric vehicle, or to an electric hub-lift vehicle. Brief description of the drawings

[0022] The features, aspects, and advantages of the present invention will be better understood in the light of the following description and the accompanying figures. The description refers to the accompanying drawings, in which:

[0023] Fig. 1 illustrates an exploded view of a power converter, configured according to one aspect of the present subject;

[0024] [Fig.2A] illustrates the power converter of [Fig.1], with the exception of a housing, and a busbar assembly removed from a shield, the busbar assembly being configured in accordance with one aspect of the present subject;

[0025] Fig. 2B illustrates a perspective view of the assembly of the omnibus bar to the shield, configured in accordance with the present subject;

[0026] Fig. 3A illustrates the assembly of the omnibus bar, configured in accordance with one aspect of the present subject;

[0027] Fig. 3B illustrates an exploded view of the busbar assembly, configured according to one aspect of the present subject;

[0028] Fig. 3C illustrates another perspective of the omnibus bar assembly illustrated in Fig. 3B;

[0029] [Fig. 3D] illustrates a top view of the busbar assembly shown in [Fig. 3C]; and

[0030] Fig. 4 is a schematic illustration of an electrical system, configured according to an example in this subject.

[0031] The figures are not necessarily to scale, and the size of some parts may be exaggerated to illustrate the example shown more clearly. Furthermore, the drawings provide examples and / or examples that conform to the description, but the description is not limited to the examples and / or examples provided in the drawings. DETAILED DESCRIPTION

[0032] In the following description, reference is made to the accompanying drawings, which form an integral part of the invention and illustrate specific embodiments in which the invention can be implemented. These embodiments are described in sufficient detail to enable a person skilled in the art to practice the invention, and it is understood that the embodiments can be combined, or that other embodiments can be used, and that structural and logical modifications can be made without departing from the scope of the present invention. The detailed description that follows should therefore not be taken in a limiting sense, and the scope of the present invention is defined by the appended claims and their equivalents.

[0033] Figure 1 illustrates an exploded view of a power converter 100, configured according to one aspect of the present subject. The power converter 100 It includes an inverter, a boost converter, and a basic bus assembly 104. The inverter and boost converter are contained within the housing 102. The inverter has an inverter circuit that converts direct current (DC) to alternating current (AC). The boost converter has a boost converter circuit that increases the voltage from a low voltage level to a high voltage level. The bus assembly 104 comprises three bus bars 106, 108, and 110 that pass through a single electromagnetic compatibility filter 112 (or EMC filter 112). The three bus bars 106, 108, and 110 comprise a positive bus bar 106, a negative bus bar 108, and a boost bus bar 110 arranged inside the housing 102 to carry the positive DC power supply, the negative DC power supply, and the output of the boost converter circuit, respectively.

[0034] According to one aspect of the present subject, the EMC filter 112 is in the form of a container. Furthermore, the three busbars 106, 108, 110 pass through a single EMC filter 112, meaning that there is only one container and that the three busbars 106, 108, 110 are encapsulated within this container. The single EMC filter 112, i.e., the container, ensures that the three busbars 106, 108, 110 are correctly aligned and secured.

[0035] This power converter 100 can be applied, for example, to an electric vehicle, and the inverter circuit can be configured to drive an electric motor (or "rotating machine") using power from a vehicle battery. The vehicle can also be equipped with a low-voltage battery to power auxiliary equipment, such as a light and a radio. In operation, the three busbars 106, 108, and 110 of the power converter 100 each serve to distribute power at different voltage levels. In "driving" mode (i.e., when the electric motor converts electrical power from the inverter to provide torque for driving the vehicle), the auxiliary busbar 110 is not directly involved in supplying power to the electric motor.In this mode, the inverter converts the DC voltage from the positive bus bar 106 and the negative bus bar 108 into AC voltage. This AC voltage is controlled to precisely match the speed and torque required by the electric motor for efficient driving. In another mode, namely "charging mode," when the EV is connected to an external charging station, the DC voltage from the external charging station enters the inverter. The boost converter increases this DC voltage to a level compatible with the vehicle's battery voltage for efficient charging. The boost bus bar 110 then facilitates the distribution of the increased voltage.

[0036] According to an example in this subject, the positive busbar 106, the negative busbar 108, and the auxiliary busbar 110 are at least partially converted into an overmolding component 114. The overmolding component 114 is made of an electrically insulating material. The overmolding component 114 has multiple through holes 120 through which fasteners can pass. The busbar 104 is mounted on a shield 118. Furthermore, the shield 118 is assembled inside the chamber 102 of the housing 103. On one side of the shield 118, the busbar 104 is mounted by means of fasteners, and on the other side of the shield 118, or lower side 122, a printed circuit board (PCB) (not shown) is mounted. The inverter circuit is integrated into the printed circuit board. The shielding 118 functions as a support to protect the components on one side of the shielding 118 from the EMC effects of the underside 122, and vice versa.Therefore, the 114 busbar is not affected by EMC effects generated by components, for example power modules, DC coupling capacitors, etc.

[0037] Figure 2A illustrates a perspective view in which the shield 118 and the busbar assembly 104 are disassembled from each other. Figure 2B illustrates a top view from another perspective of the shield 118 and the busbar 102 assembled together, configured according to one aspect of this subject. According to one aspect of this subject, the overmolded portion 114 includes a filter housing 113 in which the EMC filter 112 is housed. The overmolded portion 114 may also include housings 200a, 200b in which safety capacitors are contained, the safety capacitors being provided to help minimize the generation of EMI (electromagnetic interference) / RFI (radio frequency interference) and the adverse effects associated with received EMI / RFI. For example, enclosure 200a contains a capacitor Cx and enclosure 200b contains a capacitor Cy.The typical operation of capacitor Cx and capacitor Cy is known and is therefore not described in detail for the sake of brevity in this description.

[0038] According to one aspect of the present subject, the positive busbar 106, the negative busbar 108, and the auxiliary busbar 110 are equally spaced inside the chamber 103. Furthermore, the three aforementioned busbars 106, 108, and 110 are each formed to include multiple bends 204 according to the arrangement requirements of all the components arranged in the chamber 103 of the housing 102. Moreover, these multiple bends 204 facilitate the transfer of electrical power in the circuit (i.e., the inverter circuit, the boost converter circuit) regardless of the topological configuration of the circuit included in the power converter 100. For example, the aforementioned circuit includes relay switches (not shown in the figures) arranged on the underside 122 of the shield 118. The shield 118 is provided with a relay switch housing. 202 protrudes from the side of the shield 118 where the busbar assembly 104 is mounted. Therefore, thanks to the multiple curves 204 of the three busbars 106, 108, 110, the busbar assembly 104 is configured to accommodate the internal layout requirements inside the housing (102).

[0039] Figure 3A illustrates the busbar assembly, configured according to one aspect of this subject. Figure 3B illustrates an exploded view of the busbar assembly 104. Figure 3C illustrates a perspective view of the busbar assembly 104 with some components removed from the view, and configured according to this subject. Figure 3D illustrates a top view of the busbar assembly 104 of Figure 3C.

[0040] As described in a previous paragraph, the busbar assembly 104, and in particular the three busbars 106, 108, and 110, distributes power at different voltage levels. The three busbars 106, 108, and 110 extend between two ends where they supply or receive electrical power for distribution. These two ends can be designated as region A and region B, as shown in [Fig. 3A]. Region A represents a connected end 300 of the busbar assembly 104, more specifically the connected end of the three busbars 106, 108, and 110. Each of the three busbars 106, 108, and 110 is crimped into region A to facilitate connection with another electronic component or circuit. The connected end 300 of the positive busbar 106 is connected to the inverter circuit.The connected end 300 of the negative busbar 108 has two crimped slots, one connected to the inverter circuit and the other connected to the stator phases of the rotating machine. The connected end 300 of the auxiliary busbar 110 is also connected to the stator phases of a rotating machine. Region B represents a connector end 302 of the busbar assembly 104 where the three busbars 106, 108, 110—namely, the positive busbar 106, the negative busbar 108, and the auxiliary busbar 110—are covered by the overmolded part 114. The overmolded part 114 in region B is formed as a connector 116 which, in an electric vehicle application, is suitable for connecting to an electrical power source, such as a vehicle battery.

[0041] According to an example in the present subject, the positive busbar 106, the negative busbar 108, and the auxiliary busbar 110 are each divided lengthwise into two sections between the two regions A and B. Region C, illustrated in [Fig. 3B], represents a portion of the busbar assembly 104 where the two sections are joined together. The two sections comprise a first section and a second section. The first section extends lengthwise from the connected end 300 in section A to a free end 304 in section C. The second section extends length between the connected end 302 in section B and the second free end 306 in section B. The first free end 304 and the second free end 306 are joined together, for example, by brazing or welding.

[0042] According to an example in this subject, each of the three busbars 106, 108, 110, at the second free end 306, includes projections 310 which are soldered to the printed circuit board. These projections 310 connect to the capacitor Cy contained in the housing 200b and provide grounding via fasteners inserted into holes 230 formed near the housing 200b.

[0043] According to another example of the present object, the first part of the three busbars 106, 108, 110 comprises a straight section 316 without curves. The straight section 316 is closed at least partially by the overmolded section 114. The straight section 316 extends in a direction parallel to 314, as shown in [Fig. 3C] and [Fig. 3D]. Furthermore, the EMC filter 112 is formed to include passages extending parallel to the direction 314 and thus allows the positive busbar 106, the negative busbar 108, and the auxiliary busbar 110 to pass through. The housing of the filter 113 is open in the direction 314 from the side facing the first free end 304 to allow the EMC filter 112 to enter. The EMC filter is provided with an edge 308 which is locked in an opening 312 formed on the housing of the filter 113.

[0044] Figure 4 is a schematic illustration of an electrical system 400 comprising a rotating machine 408, an electrical power source 406, and the power converter 100 configured according to the present subject. In charging mode, there is a flow of electrical energy from an external power source (e.g., an external charging station) to the rotating machine 408 via the auxiliary busbar 110. From the rotating machine 408, the electrical energy is routed to the inverter circuit 402 via the phase connectors (410) of the rotating machine 408. From the inverter circuit 402, the positive busbar 106 and the negative busbar 108 facilitate the flow of electrical energy to the electrical power source 406, for example, a battery...

[0045] According to one example, the external power source (not shown) is electrically connected to the electrical system 400 by means of a charging cable (not shown).

[0046] In one example, the electrical system 400 can be applied to an electric vehicle. The inverter circuit 402 drives the rotating machine 408 using energy supplied by the electrical power source 406. The rotating machine 408 is a polyphase machine, and preferably a three-phase rotating machine 408. Therefore, the inverter 402 is configured to power the three-phase rotating machine 408. The electric vehicle can also be equipped with a low-voltage battery to power auxiliary devices, such as a light and a radio. In operation, the three busbars 106, 108, 110 of the power converter Each of the 100 busbars serves to distribute current at different voltage levels. In "driving" mode, the auxiliary busbar 110 is not directly involved in powering the rotating machine 408. In this mode (i.e., driving mode), the inverter circuit 402 converts the DC voltage from the positive busbar 106 and the negative busbar 108 into AC voltage. This AC voltage is controlled to precisely match the speed 408 of the rotating machine and the torque required for efficient driving. The auxiliary busbar 110 remains inactive or operates to regulate the power supply to high-voltage accessories (if any), but does not supply power to the rotating machine 408. In charging mode, when the EV is connected to an external charging station (not shown), the DC voltage from the external charging station enters the inverter circuit 402.The boost converter circuit 404 raises this DC voltage to a level compatible with the voltage of the electrical power source 406 for efficient charging. The boost busbar 110 thus facilitates the distribution of the increased voltage. The three busbars 106, 108, and 110 pass through a single EMC filter 112, which is snap-fitted to the filter housing 113 formed on the overmolded portion 114.

[0047] Various modifications to the disclosed embodiments, as well as to other embodiments of the object, will become apparent to those with relevant knowledge by referring to the description of the object. It is therefore envisaged that such modifications will be made without departing from the scope of this subject.

Claims

Demands

1. Power converter (100) comprising: an inverter equipped with an inverter circuit (402) adapted for converting direct current (DC) into alternating current (AC), the inverter being contained in a housing (102); a boost converter contained in the housing (102) and having a boost converter circuit (404) adapted for increasing the voltage from a low voltage level to a high voltage level; and a set of busbars (104) comprising three busbars (106; 108; 110) passing through a single electromagnetic compatibility (EMC) filter (113), the three busbars (106; 108; 110) comprising: a positive busbar (106), a negative busbar (108) and a boost busbar (110), arranged inside said housing (102) to conduct the positive DC supply, the negative DC supply and the output of said boost converter circuit (404), respectively.

2. Power converter (100) according to claim 1, wherein the positive busbar (106), the negative busbar (108) and the auxiliary busbar (110) are at least partially covered by an overmolding piece (114) made of electrically insulating material, the overmolding piece (114) comprising multiple through holes (202) into which fasteners are inserted.

3. Power converter (100) according to the preceding claim, wherein the positive busbar (106), the negative busbar (108) and the auxiliary busbar (110) are equally spaced inside the housing (102).

4. Power converter (100) according to any one of the preceding claims, wherein the positive busbar (106), the negative busbar (108) and the auxiliary busbar (110) are each composed of multiple curves (204) adapted to the operating requirements of the internal arrangement in the housing (102).

5. Power converter (100) according to the preceding claim, wherein the positive busbar (106), the negative busbar (108) and the auxiliary busbar (110) are each divided into two sections of length, the two sections being: a first section comprising a first free end (304) and a connected end (300) at each end along the length of the first section, the connected end (300) of the positive busbar (106) and the negative busbar (108) being connected to the inverter circuit (402) and the connected end (300) of the auxiliary busbar (110) being adapted to connect to the stator phases of a rotating machine; and a second section comprising a second free end (306) and a connector end (302) at each end along the length of the second section, the connector end (302) being adapted to connect to an electrical power source (406).

6. Power converter (100) according to the preceding claim, wherein the first free end (304) and the second free end (306) are assembled by brazing or welding.

7. Power converter (100) according to the preceding claim, wherein one of the two sections comprises a straight portion (316) devoid of curves, which passes through the EMC filter (112).

8. Power converter (100) according to the preceding claim, wherein the overmolded portion (114) further comprises a filter housing (113) in which the electromagnetic compatibility (EMC) filter (112) is housed.

9. Power converter (100) according to the preceding claim, wherein the filter housing (113) includes a snap-in opening (312) through which a snap-in ridge (308), formed on the electromagnetic compatibility (EMC) filter (112), is inserted.

10. Power converter (100) according to the preceding claim, wherein the overmolded portion (114) further comprises housings (200a; 200b) in which the capacitor modules are housed.

11. Electrical system (400) comprising a rotating machine (408); an electrical power source (406); and a power converter (100), configured according to any one of the preceding claims.

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