US-12627201-B2 - Cooling system for an electric traction machine for a motor vehicle

US12627201B2US 12627201 B2US12627201 B2US 12627201B2US-12627201-B2

Abstract

A cooling system for an electric traction machine, including a circulation system for guiding a first cooling liquid, a first circulation pump for conveying the first cooling liquid in the circulation system, and a motor inlet connection for fluidically connecting the circulation system on an inlet side to a first winding head region of an electric traction machine intended to be temperature-controlled. The cooling system includes a motor outlet connection for fluidically connecting the circulation system on an outlet side to a second winding head region of an electric traction machine intended to be temperature-controlled, and a first heat exchanger for dissipating heat from and/or supplying heat to the first cooling liquid. A plurality of cooling grooves are arranged between the winding head regions to guide the first cooling liquid. Respective highest locations on the winding head regions are fluidically connected to each other by a second deaeration line.

Inventors

Stefan Oechslen
Simon Kuebler

Assignees

DR. ING. H.C. F. PORSCHE AKTIENGESELLSCHAFT

Dates

Publication Date: 20260512
Application Date: 20230922
Priority Date: 20221005

Claims (18)

1 . A cooling system for an electric traction machine for a motor vehicle, the cooling system comprising: a circulation system for guiding a first cooling liquid that is circulating; a first circulation pump for conveying the first cooling liquid in the circulation system; a motor inlet connection for fluidically connecting the circulation system on an inlet side to a first winding head region of an electric traction machine intended to be temperature-controlled; a motor outlet connection for fluidically connecting the circulation system on an outlet side to a second winding head region of the electric traction machine intended to be temperature-controlled; and a first heat exchanger for dissipating heat from and/or supplying heat to the first cooling liquid circulating in the circulation system, wherein the electric traction machine comprises a plurality of cooling grooves, which are arranged between the winding head regions and used to guide the first cooling liquid, and wherein a first deaeration line is provided, by which, given a predetermined orientation of the electric traction machine in the Earth's gravitational field, respective highest locations on the winding head regions are fluidically connected to each other.
2 . The cooling system according to claim 1 , wherein an AC housing is further provided for an AC power connection for the electric traction machine, wherein a temperature of the AC housing and/or an AC power connection in the AC housing can be controlled by the first cooling liquid, and wherein a second deaeration line is provided between the AC housing and one of the winding head regions.
3 . The cooling system according to claim 2 , wherein the second deaeration line is, given the predetermined orientation of the electric traction machine, indirectly or directly fluidically connected to at least one of the following highest locations in the Earth's gravitational field: to the highest location on the AC housing; to the highest location on the first winding head region; and to the highest location on the second winding head region.
4 . The cooling system according to claim 2 , wherein the AC housing is provided with at least one further connecting line to a motor input terminal and/or to the first winding head region, and wherein the at least one further connecting line is, given the predetermined orientation of the electric traction machine in the Earth's gravitational field, arranged below the second deaeration line.
5 . A thermal management module for a powertrain of a motor vehicle, the module comprising: for a transmission, an oil circuit with a second circulation direction and with a second heat exchanger; for at least one vehicle component, a water circuit with a third circulation direction and with a third heat exchanger; and for an electric traction machine, the cooling system according to claim 1 .
6 . The thermal management module according to claim 5 , wherein the water circuit is connected to the first heat exchanger of the cooling system for an electric traction machine for heat transfer.
7 . The thermal management module according to claim 6 , wherein the water circuit is additionally connected to the second heat exchanger of the oil circuit for heat transfer.
8 . A powertrain for a motor vehicle, the powertrain comprising: at least one electric traction machine for providing a torque; at least one propulsion wheel for propelling the motor vehicle by a torque from the at least one electric traction machine; at least one transmission for conducting a torque between the electric traction machine and at least one of the at least one propulsion wheels; and the cooling system according to claim 1 for at least one of the at least one electric traction machine, at least one of the at least one transmission, and at least one vehicle component for at least one of the at least one electric traction machine.
9 . A motor vehicle, comprising: a chassis with a transport compartment; and the powertrain according to claim 8 for propelling the motor vehicle.
10 . The cooling system according to claim 2 , wherein the second deaeration line is provided between the AC housing and the first of the winding head region.
11 . The thermal management module according to claim 5 , wherein a pulse inverter for the electric traction machine is arranged in the water circuit.
12 . The thermal management module according to claim 6 , wherein the water circuit is connected to the first heat exchanger as the only liquid-bonded heat transfer from the cooling system to the environment.
13 . The thermal management module according to claim 6 , wherein in the third circulation direction of the water circuit, a pulse inverter for an electric traction machine is arranged upstream of the first heat exchanger.
14 . The thermal management module according to claim 7 , wherein the water circuit is additionally connected to the second heat exchanger as the only liquid-bonded heat transfer from the cooling system to the environment.
15 . The thermal management module according to claim 7 , wherein in the third circulation direction of the water circuit, the first heat exchanger is arranged upstream of the second heat exchanger.
16 . A powertrain for a motor vehicle, the powertrain comprising: at least one electric traction machine for providing a torque; at least one propulsion wheel for propelling the motor vehicle by a torque from the at least one electric traction machine; at least one transmission for conducting a torque between the electric traction machine and at least one of the at least one propulsion wheel; and the thermal management module according to claim 5 for at least one of the at least one electric traction machine, at least one of the at least one transmission, and at least one vehicle component for at least one of the at least one electric traction machine.
17 . The powertrain according to claim 16 , wherein the at least one vehicle component is a pulse inverter.
18 . The powertrain according to claim 8 , wherein the at least one vehicle component is a pulse inverter.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application claims benefit to German Patent Application No. DE 10 2022 125 587.5, filed on Oct. 5, 2022, which is hereby incorporated by reference herein. FIELD The invention relates to a cooling system for an electric traction machine for a motor vehicle. The invention further relates to a thermal management module for a powertrain of a motor vehicle, a powertrain with such a thermal management module for a motor vehicle, and a motor vehicle with such a powertrain. BACKGROUND Cooling systems for electric traction machines used in order to dissipate the resulting waste heat in case of a power demand are known from the prior art. In regard to increased cooling performance, the idea is to use a coolant directly flowing through at least the stator of an electric traction machine, wherein the coolant should be designed as a dielectric cooling liquid. It is advantageous to cool as few components as possible in this dielectric cooling system. Other components of a powertrain in which such an electric traction machine is integrated, e.g., a transmission and a pulse inverter, are preferably cooled in at least one separate cooling circuit. A transmission is, e.g., cooled using an oil circuit such that the coolant (transmission oil) is simultaneously configured to lubricate the transmission components. A pulse inverter is, e.g., arranged in a water circuit, using which even further vehicle components are preferably coolable. If a traction machine is directly cooled, then (as mentioned) it is necessary that the cooling liquid (a dielectric material) be the most effective electric insulator possible. When air entrainments are present, both this electrically insulating property and the heat capacity will decrease. Therefore, the goal is to minimize the air in the line system and, above all, for it not to remain there. SUMMARY In an embodiment, the present disclosure provides a cooling system for an electric traction machine for a motor vehicle, the cooling system comprising a circulation system for guiding a first cooling liquid that is circulating, a first circulation pump for conveying the first cooling liquid in the circulation system, and a motor inlet connection for fluidically connecting the circulation system on an inlet side to a first winding head region of an electric traction machine intended to be temperature-controlled. The cooling system further comprises a motor outlet connection for fluidically connecting the circulation system on an outlet side to a second winding head region of an electric traction machine intended to be temperature-controlled, and a first heat exchanger for dissipating heat from and/or supplying heat to the first cooling liquid circulating in the circulation system. The electrical traction machine comprises a plurality of cooling grooves, which are arranged between the winding head regions and used to guide the first cooling liquid. A second deaeration line is provided, by which, given a normal orientation of the electrical traction machine in the Earth's gravitational field, respective highest locations on the winding head regions are fluidically connected to each other. BRIEF DESCRIPTION OF THE DRAWINGS Subject matter of the present disclosure will be described in even greater detail below based on the exemplary figures. All features described and/or illustrated herein can be used alone or combined in different combinations. The features and advantages of various embodiments will become apparent by reading the following detailed description with reference to the attached drawings, which illustrate the following: FIG. 1 illustrates a schematic diagram of a thermal management module; FIG. 2 illustrates a first spatial view of a cooling system; FIG. 3 illustrates a second spatial view of the cooling system according to FIG. 2; and FIG. 4 illustrates a schematic top view of a motor vehicle with a thermal management module. DETAILED DESCRIPTION In an embodiment, the present invention overcomes the disadvantages known from the prior art. The features of the disclosure can be combined in any technically advantageous manner, wherein the explanations in the following description as well as features in the drawings, which include explanatory configurations of embodiments of the invention, can also be used for this purpose. In an embodiment, the invention relates to a cooling system for an electric traction machine for a motor vehicle, said cooling system comprising at least the following components: a circulation system for guiding a first cooling liquid that is circulating;a first circulation pump for conveying the first cooling liquid in the circulation system;a motor inlet connection for fluidically connecting the circulation system on the inlet side to a first winding head region of an electric traction machine intended to be temperature-controlled;a motor outlet connection for fluidically connecting the circulation system on the outlet side to