ELECTRICAL ARRANGEMENT OF AN ELECTRICAL BUSBAR AND A COOLING MODULE

Description

DOMAINE TECHNIQUE DE L'INVENTION

[0001] The present invention relates to the field of electrical equipment, in particular for vehicles, such as inverters.

[0002] More specifically, the present invention relates to a subset of such equipment, namely an electrical assembly formed on a cooling module and comprising an electrical connection bar. ETAT DE LA TECHNIQUE

[0003] In many electrical equipment, particularly power electrical equipment such as inverters intended to supply power to a vehicle electric motor, cooling modules are provided.

[0004] A cooling module, as it is known, is used to dissipate heat produced by electrical components, such as electronic cards or capacitive elements in particular.

[0005] An active cooling module involves an external body, in particular a cooling liquid such as water for example, the circulation of which, between an inlet and an outlet of the cooling module, said cooling module being arranged near or in contact with at least one element to be cooled, makes it possible to lower the temperature of said element to be cooled.

[0006] A passive cooling module, also known as a heat sink, does not involve any external body. A heat sink is generally made of a material with good thermal conductivity. It may include radiator elements, fins, intended to promote heat dissipation.

[0007] In electrical equipment such as a power inverter, an active cooling module is used. In the following, the term "cooling module" refers to an active cooling module.

[0008] On the other hand, in the assembly processes of electrical equipment, improved modularity is now sought, in particular to facilitate assembly by using independent sub-assemblies from a single piece.

[0009] Document US2004 / 256710A1 proposes a device with power semiconductor components fixed on one side of a cooled support body, the other side of which carries a reservoir capacitor. Conductive bars, in addition to the power semiconductor components, are fixed to the cooled support body.

[0010] In this context, the present invention relates to an electrical assembly formed on a cooling module, a portion of which receives, directly fixed to said module, an electrical connection bar in particular intended to receive at least one electrical connector of third-party electrical equipment. For example, in the context of a vehicle inverter, said electrical connection bar may be an alternative electrical connection bar, also called "AC busbar" in English, intended to receive phase connectors of an electric motor of the vehicle. PRESENTATION DE L'INVENTION

[0011] To this end, the present invention relates to an electrical assembly comprising a cooling module, in particular an active cooling module comprising a cooling liquid circulation network, and an electrical connection bar, said electrical connection bar being directly fixed to a receiving portion of the cooling module, said electrical assembly being intended to be attached to a chassis of a first piece of electrical equipment.

[0012] According to one embodiment, the electrical connection bar is screwed onto the receiving portion of the cooling module.

[0013] According to the invention, a power electronic module fixed on a first surface of the cooling module and a capacitive connecting element fixed on a second surface, opposite the first surface, of the cooling module.

[0014] According to one embodiment, said receiving portion comprises opposite faces which are respectively in the same plane as the first surface of the cooling module and the second surface of the cooling module.

[0015] According to the invention, the cooling module comprises a first portion comprising the first and second surfaces, and wherein said receiving portion forms a fork extending from the first portion of the cooling module.

[0016] The electrical connection bar according to the invention comprises: a first part held between two arms of the fork. According to one embodiment, it also comprises: a transverse arm extending from one side of the first portion, said transverse arm being located at the junction of the fork with the first portion of the cooling module, said transverse arm extending along the first surface of the cooling module and comprising connection terminals which come opposite terminals of said power module to be connected thereto.

[0017] According to one embodiment, the cooling module comprises a coolant inlet and a coolant outlet, the cooling module being configured such that the coolant circulates between the power electronic module and the capacitive connecting element.

[0018] According to one embodiment, the electrical connection bar comprises a body made of electrically insulating material holding together conductors of the electrical connection bar, said body coming against the cooling module so as to allow thermal dissipation of the heat from the conductors towards the cooling module.

[0019] The present invention also relates to electrical equipment comprising a housing in which is housed an electrical assembly as briefly described above.

[0020] According to one embodiment, said electrical equipment forms an inverter. PRESENTATION DES FIGURES

[0021] The invention will be better understood on reading the following description, given solely by way of example, and referring to the appended drawings given as non-limiting examples, in which identical references are given to similar objects and in which: Fig. 1 : there figure 1 represents an example of an electrical assembly according to the invention; Fig. 2 : there figure 2 represents the example of an electrical assembly according to the preceding invention, to which an electronic power module and a capacitive connecting element are fixed; Fig. 3 : there figure 3 shows an example of electrical equipment, in this case an inverter, comprising an electrical assembly according to an example of the invention; Fig. 4 : there figure 4 shows a cooling module for an electrical assembly according to an example of the invention; Fig. 5 : there figure 5 shows an electrical connection bar intended for an electrical assembly according to an example of the invention.

[0022] It should be noted that the figures set out the invention in detail to implement the invention, said figures can of course be used to better define the invention if necessary. DESCRIPTION DETAILLEE DE L'INVENTION

[0023] In the description which will be given below, the invention will be described mainly with a view to the production of an inverter, in particular intended to power an electrical machine such as a rotating electrical machine of a vehicle motorization system. However, the invention also relates to any electrical equipment capable of comprising an electrical assembly as described below.

[0024] In reference to the figure 1 , an electrical assembly 10 is proposed comprising a cooling module 11 of which a receiving portion 110 receives, directly fixed to said cooling module 11, an electrical connection bar 12.

[0025] For example, the electrical connection bar 12 is screwed to the cooling module 11. Alternatively, the electrical connection bar 12 can be fixed to the cooling module by riveting or by embedding via grooves, or by any other means.

[0026] A first advantage lies in the fact that the direct contact between the electrical connection bar 12 and the cooling module 11 makes it possible to cool the electrical connection bar 12. Indeed, in use of the electrical equipment to which the electrical assembly 10 relates, when the electrical connection bar 12 receives electrical connectors, for example phase connectors of a vehicle electric motor when the electrical equipment is a power inverter of a vehicle, heating of said electrical connection bar 12 occurs.

[0027] In the same context, the electrical connection bar 12 also comprises electrical conductors 120 with terminals 122 intended to be connected to corresponding terminals of third-party electrical equipment, for example a motor, which contributes to producing heating of the electrical connection bar 12.

[0028] The receiving portion 110 extends from a first portion 118 of the cooling module 11, said first portion 118 having a first surface 114 and a second surface 115, said first and second surfaces 114, 115 being intended to receive respectively, still according to the example mentioned above, an electronic power module and a capacitive connecting element.

[0029] More precisely, as represented in the figure 2 , the electrical connection bar 12 comprises electrical conductors 120, in particular, according to one embodiment, flat conductors of the “leadframe” type according to the commonly used English term. Electrical terminals 123 of the electrical conductors 120 are intended, at one end of the electrical connection bar 12, to be received by electrical terminals of an electrical device such as a power electronic module 20 of an inverter, said power electronic module 20 being fixed to the cooling module 11 and cooled by the latter. According to this embodiment, on the other hand, the electrical connection bar 12, at the end opposite the first end, comprises electrical terminals 122 intended to receive phase connectors of an electric motor powered by the inverter via the power electronic module 20.

[0030] As shown in the figure 1 , the cooling module 11 comprises for example a coolant inlet 111 and a coolant outlet 112.

[0031] Thus, in particular, the cooling liquid circulates in channels located between the first and second surfaces 114, 115 of the cooling module 11. The inlet 111 and the outlet 112 of the cooling liquid are for example arranged in the second surface 115 of the cooling module 11, that is to say on the surface to which the capacitive connecting element 30 is fixed, on the side opposite the first surface 114 to which the power electronic module 20 is fixed on the figure 2 .

[0032] The electrical connection bar 12 may comprise a transmission module 13. The transmission module 13, integrated in the electrical connection bar 1, is in particular configured to connect to an electrical connector of an electrical device to take an electrical signal representative of a physical property of said electrical device. Such electrical device is for example an electric motor controlled by the power electronic module 20, the transmission module 13 transmitting a signal representative of the position of the motor to for example a control card of the inverter.

[0033] According to one embodiment, a body 121 made of electrically insulating material is provided in the electrical connection bar 12 to hold the electrical conductors 120 together, and to electrically insulate them between their electrical terminals 122, 123. However, the body may be made of a material promoting thermal exchanges with the cooling module 11. In particular, the body 121 may be overmolded, glued, or force-mounted on the electrical conductors 120, before the electrical connection bar 12 is attached and fixed to said cooling module 11, at the receiving portion.

[0034] Furthermore, it is specified that a thermal interface can also be provided between the electrical connection bar 12 and the cooling module 11, in particular along the body 21 of the electrical connection bar 12. Such a thermal interface can be made of a TIM type material (for “Thermal Interface Material”).

[0035] As shown in the figure 1 , the electrical assembly 10, comprising the cooling module 12 and the electrical connection bar 12 fixed on a receiving portion 110 of said cooling module 11, makes it possible to improve the rigidity of said electrical connection bar 12.

[0036] A seal 14 may be held in position on the body 21, around the connecting bar 12 to come, in particular against a chassis of the electrical equipment when the electrical conductors 120 pass through an opening in the chassis to connect to third-party electrical equipment, in particular an electric motor.

[0037] There figure 3 represents, in isolation, a cooling module 11, such as intended to form part of an electrical assembly according to an example of the invention. The figure 4 represents, in isolation, a complementary connection bar 12, such as intended to form part of an electrical assembly according to the same example of the invention.

[0038] In detail, according to the embodiment shown on the figure 3 , the cooling module 11 has a first portion 118 and a receiving portion 110. The first portion 118 comprises the first surface 114 and the second surface 115. The receiving portion 110 comprises opposite faces which are respectively in the same plane as the first surface 114 of the cooling module 11 and the second surface 115 of the cooling module 11. The cooling module 11 may comprise a cavity 119 intended to receive current sensors measuring the currents between the power electronic module 20 and the electrical connection bar 12. The current sensors comprise for example C-magnetics 40 (visible on the figure 2 ).

[0039] Furthermore, always depending on the method of realization of the figure 3 , in accordance with the invention, the receiving portion 110 forms a fork extending from the first portion 118 of the cooling module 11, said fork comprising two arms 116, 117.

[0040] In reference to the figure 4 , the electrical connection bar 12, correspondingly, comprises a first part 124 intended to be held between the two arms 116, 117 of the fork which forms the receiving portion 110 (as shown elsewhere in the figure 2 ). The electrical connection bar 12 further comprises a transverse arm 125 extending from one side of the first portion 124, said transverse arm 125 being intended to be located at the junction of the fork with the first portion 118 of the cooling module 11. The transverse arm 125 extends along the first surface 114 of the cooling module 11 and comprises the connection terminals 123 which are intended to be located opposite terminals of a power module 20 fixed on said first surface 114 of the cooling module 11, to be connected thereto (as shown elsewhere in the figure 2 ).

[0041] In reference to the figure 5 , the electrical assembly 10 according to the invention is intended to be integrated into electrical equipment 1, in particular an inverter.

[0042] The electrical equipment comprises an electrical assembly 10 according to the invention, with a cooling module and an electrical connection bar, said cooling module being sandwiched between a power electronic module 20 and a capacitive connecting element 30.

[0043] On the figure 5 , a chassis 2 is shown inside which is housed an electrical assembly 10, in particular equipped with an electronic power module and a capacitive connecting element, said chassis 2 being closed by a cover 3.

[0044] In particular, a power electronic module 20 is an assembly comprising a plurality of semiconductor chips forming an electrical circuit encapsulated in the same envelope. More precisely, in the present case, the power electronic module 20, as shown in the figure 2, may be an assembly comprising components through which energy passes to power an electrical machine, for example an electric motor, said components being in particular intended to transform a direct current into alternating currents or vice versa. Such an electronic power module 20 is configured to allow a controlled passage of electrical energy between a high-voltage power supply battery and the electrical machine.

[0045] Furthermore, by “capacitive link element” 30 is meant a capacitive element, also called “DC-link capacitor” in English, providing a filtering function, in particular to stabilize the voltage supplied to the electronic power module.

[0046] Thus, the cooling module 11 is firstly configured to cool, on the one hand, the power electronic module 20 and, on the other hand, the capacitive connecting element 30.

[0047] According to the invention, the cooling module 11 also cools the electrical connection bar 12.

[0048] In the embodiment according to which the electrical equipment 1 is an inverter, the electrical connection bar 12 is in particular an alternative connection bar, intended to receive phase connectors of an electric motor supplied with energy by said inverter, in particular at the level of the electrical terminals 122 located at the second end of the connection bar 120.

[0049] According to the invention, the cooling module 11 thus provides a support function on which the electrical connection bar 12 is assembled and maintained.

[0050] Furthermore, the electrical assembly 10 according to the invention makes it possible to integrate the electrical connection bar 12 into the cooling control of the electrical equipment to which said electrical assembly relates.

[0051] The cooling module 11, within the electrical assembly 10 which it forms with the electrical connection bar 12, provides, with respect to said electrical connection bar 12, both a cooling function and a stiffening function.

[0052] Concerning the stiffening function, it is specified that the improvement is for example obtained due to the direct fixing of the electrical connection bar 12 to the cooling module 11.

[0053] It is also specified that an advantage of the invention lies in the fact that the electrical assembly 10, comprising the cooling module 11 and the electrical connection bar 12, fixed to said cooling module, in particular by screwing, is in one piece. Said electrical assembly 10 therefore constitutes an independent assembly whose functions can be tested separately.

[0054] In particular, on the basis of the electrical assembly 10 according to the invention, it is possible to assemble an electronic power module 20 and a capacitive connecting element 30 to form an inverter subassembly 100.

[0055] Such an inverter subassembly 100 can be tested independently, which improves the modularity of an inverter assembly process.

[0056] Once independently tested, the basic electrical assembly 10 or the inverter subassembly 100 can be returned to a chassis 2 closed by a cover 3 to form electrical equipment 1, such as an inverter.

Claims

1. Electrical assembly (10) comprising a cooling module (11), notably an active cooling module (11) comprising a cooling-liquid circulation network, and a busbar (12), said busbar (12) being directly attached to a receiving portion (110) of the cooling module (11), said electrical assembly (10) being intended to be fitted in a frame (2) of a first item of electrical equipment (1), said electrical assembly additionally comprising a power electronics module (20) attached to a first surface (114) of the cooling module (11) and a connecting capacitive element (30) attached to a second surface (115), opposite the first surface (114), of the cooling module (11), the cooling module having a first portion (118) comprising the first and the second surface (114, 115), the assembly being characterized in that said receiving portion (110) forms a fork extending from the first portion (118) of the cooling module (11), the busbar (12) comprising a first part (124) held between two arms (116, 117) of the fork.

2. Assembly according to Claim 1, wherein said receiving portion (110) comprises opposite faces which are respectively in the same plane as the first surface (114) of the cooling module (11) and as the second surface (115) of the cooling module (11).

3. Electrical assembly according to Claim 1 or 2, wherein the busbar (12) comprises a transverse arm (125) extending from one side of the first part (124), said transverse arm (125) being situated at the junction between the fork and the first portion (118) of the cooling module (11), said transverse arm (125) extending along the first surface of the cooling module (11) and comprising connection terminals (123) which face terminals of said power module (20) in order to be connected thereto.

4. Electrical assembly (10) according to one of the preceding claims, wherein the cooling module (11) has a cooling-liquid inlet (111) and a cooling-liquid outlet (112), the cooling module (11) being configured such that the cooling liquid circulates between the power electronics module (20) and the connecting capacitive element (30).

5. Electrical assembly (10) according to one of the preceding claims, wherein the busbar (12) comprises a body (121) made of electrically insulating material holding the conductors (122, 123) of the busbar (12) together, said body (121) abutting the cooling module (11) in such a way as to enable thermal dissipation of the heat from the conductors (122, 123) towards the cooling module (11).

6. Item of electrical equipment (1) comprising a casing (2) which accommodates an electrical assembly (10) according to one of the preceding claims.

7. Item of electrical equipment (1) according to Claim 6, forming an inverter.