WO2024082169A1

WO2024082169A1 - Thermal management system, electric motor control method and vehicle

Info

Publication number: WO2024082169A1
Application number: PCT/CN2022/126130
Authority: WO
Inventors: 李朋涛; 庄朝晖; 马国龙
Original assignee: 宁德时代新能源科技股份有限公司; 宁德时代(上海)智能科技有限公司
Priority date: 2022-10-19
Filing date: 2022-10-19
Publication date: 2024-04-25
Also published as: CN118235282A

Abstract

Provided in the embodiments of the present application are a thermal management system, an electric motor control method and a vehicle. The thermal management system comprises: a first heat exchange loop, which comprises a first electric motor and a battery pack; a second heat exchange loop, which comprises a second electric motor and a heat storage branch, the heat storage branch being used for storing and releasing heat generated by the second electric motor; and a heat exchange medium, which is used for exchanging heat in the first heat exchange loop and/or the second heat exchange loop.

Description

Thermal management system, motor control method and vehicle

Technical Field

The present application relates to the technical field of thermal efficiency cycles, and more specifically, to a thermal management system, a motor control method and a vehicle.

Background technique

With the development of new energy technologies, batteries are increasingly being used in various electrical devices, such as mobile phones, laptops, electric vehicles, electric airplanes, electric ships, etc.

Taking electric vehicles among electrical devices as an example, in the process of rapid development of electric vehicles, problems such as their endurance, battery life, safety, comfort, and efficiency have begun to emerge, becoming an important factor hindering the development of electric vehicles.

Compared with traditional fuel vehicles, the main problem of electric vehicles is the shorter driving range. For example, when the ambient temperature is low, the battery efficiency is low at low temperatures, which leads to a significant reduction in driving range. Under normal temperature conditions, when the actual temperature of various components in the electric drive system of electric vehicles is different from the normal temperature range, it will also affect the efficiency of the electric drive system. For example, when the lubricating oil temperature in the motor fails to reach the appropriate temperature range, the motor assembly efficiency will be reduced, resulting in a reduction in driving range.

Summary of the invention

The present application provides a thermal management system, a motor control method and a vehicle, which can improve the technical problem that existing electrical devices have low efficiency under the influence of temperature factors.

In a first aspect, an embodiment of the present application provides a thermal management system, the thermal management system comprising:

A first heat exchange circuit includes a first motor and a battery pack;

The second heat exchange circuit includes a second motor and a heat storage branch; the heat storage branch is used to store and release the heat generated by the second motor;

A heat exchange medium is used for exchanging heat in the first heat exchange circuit and/or the second heat exchange circuit.

In the technical solution of the embodiment of the present application, by setting the first heat exchange circuit and the second heat exchange circuit, the heat exchange medium can flow in the first heat exchange circuit or the second heat exchange circuit and exchange heat with each module in the circuit. In a low temperature environment, when the temperature of the battery pack is low, the first motor can be controlled to operate, and the first heat exchange circuit can be turned on. The heat generated when the first motor is running can be absorbed by the heat exchange medium and the battery pack can be heated to improve the output efficiency of the battery pack. When the temperature of the battery pack is within a suitable temperature range, the second motor can be controlled to operate, and the second heat exchange circuit can be turned on. The heat generated when the second motor is running can be stored through the heat storage branch to improve the efficiency of the second motor. By improving the efficiency of the battery pack or the efficiency of the second motor, the influence of temperature factors can be reduced and the overall efficiency can be improved. When the thermal management system is applied to electric vehicles, the vehicle's cruising range can also be improved.

In some embodiments, the thermal power loss of the first motor is greater than the thermal power loss of the second motor. By setting the thermal power loss of the two motors to be different, the battery pack can be heated by driving the motor with greater heat to improve the battery efficiency. Alternatively, the motor with less heat can be driven to improve the motor efficiency.

In some embodiments, the thermal management system further includes: a motor cooling branch, the first motor and the second motor are located in the same motor cooling branch; a first switch, including a first end, a second end and a third end, respectively connected to the motor cooling branch, the battery pack and the heat storage branch; when the first switch connects the first end with the second end, a first heat exchange loop is formed; when the first switch connects the first end with the third end, a second heat exchange loop is formed. Through the conduction control of the first switch, the first motor can heat the battery pack or the second motor can store heat.

In some embodiments, the thermal management system further includes: a motor cooling branch, the first motor and the second motor are located in different motor cooling branches; a second switch, including a first end, a second end and a third end, respectively connected to the first motor, the battery pack and the heat storage branch; a third switch, including a first end, a second end and a third end, respectively connected to the second motor, the battery pack and the heat storage branch. Through the conduction control of the second switch and the third switch, the first motor can be driven to heat the battery pack or the second motor can be driven to store heat for itself.

In some embodiments, the thermal management system further includes: a heat dissipation module connected in parallel with the heat storage branch and used to form a third heat exchange loop with the second motor. When the temperature of the second motor is high, the heat dissipation module can be used to dissipate heat from the second motor to reduce the temperature of the second motor.

In some embodiments, the thermal management system includes: a fourth switch including a first end, a second end and a third end, which are respectively connected to the first motor, the heat storage branch and the heat dissipation module; when the second switch connects the first end with the second end, a second heat exchange circuit is formed; when the second switch connects the first end with the third end, a third heat exchange circuit is formed. By controlling the conduction of the fourth switch, the second motor can be switched between heat storage and heat dissipation.

In some embodiments, the first switch, the second switch, the third switch and the fourth switch are three-way proportional valves. Setting each switch as a three-way proportional valve can also achieve further flow control by controlling the opening of the valve, thereby adjusting the heating efficiency or heat storage efficiency.

In some embodiments, the first motor is an induction asynchronous motor, and the second motor is a permanent magnet synchronous motor. By setting the two motors to be different types of motors, the heat generation and efficiency of the two motors can be different, which facilitates the selection of a suitable motor for driving operation in actual situations.

In some embodiments, the first heat exchange circuit further includes a first medium transmission module, which is used to drive the heat exchange medium to circulate in the first heat exchange circuit; the second heat exchange circuit further includes a second medium transmission module, which is used to drive the heat exchange medium to circulate in the second heat exchange circuit. By setting the corresponding medium transmission modules, the heat exchange medium can be driven to circulate in the heat exchange circuit, thereby achieving heat exchange.

In the second aspect, the embodiment of the present application also provides a motor control method, which is applied to the thermal management system in the above embodiment, and the method includes: obtaining the battery temperature of the battery pack; when the battery temperature is lower than the first temperature range, controlling the first motor to run and turning on the first heat exchange circuit; when the battery temperature is within the first temperature range, controlling the second motor to run. By driving the appropriate motor to run according to the battery temperature and turning on the corresponding heat exchange circuit, the battery temperature can be adjusted, and the appropriate motor can be selected to drive the operation, so as to improve the battery efficiency or the motor efficiency.

In some embodiments, when the battery temperature is within the first temperature range, after controlling the operation of the second motor, it also includes: obtaining the lubricating oil temperature of the second motor; when the lubricating oil temperature is lower than the second temperature range, turning on the second heat exchange circuit; when the lubricating oil temperature is higher than the second temperature range, turning on the third heat exchange circuit.

In a third aspect, an embodiment of the present application further provides a vehicle, the vehicle comprising the thermal management system in the above embodiment.

In some embodiments, the first motor is a front-drive motor, and the second motor is a rear-drive motor.

The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without creative work.

FIG1 is a schematic diagram of a module structure of a thermal management system provided in one embodiment of the present application;

FIG2 is a schematic diagram of a module structure of a thermal management system provided in another embodiment of the present application;

FIG3 is a schematic diagram of a module structure of a thermal management system provided in another embodiment of the present application;

FIG4 is a schematic diagram of a module structure of a thermal management system provided in yet another embodiment of the present application;

FIG5 is a schematic diagram of a module structure of a thermal management system provided in another embodiment of the present application;

FIG6 is a schematic diagram of a module structure of a thermal management system provided in yet another embodiment of the present application;

FIG7 is a schematic diagram of a module structure of a thermal management system provided in yet another embodiment of the present application;

FIG8 is a schematic diagram of a module structure of a thermal management system provided in yet another embodiment of the present application;

FIG9 is a schematic diagram of a module structure of a thermal management system provided in yet another embodiment of the present application;

FIG10 is a schematic diagram of a module structure of a thermal management system provided in yet another embodiment of the present application;

FIG. 11 is a flow chart of a motor control method provided in an embodiment of the present application.

In the drawings, the drawings are not drawn to scale.

In the attached figure:

10. First motor; 20. Second motor; 30. Battery pack; L1. Heat storage branch; 41. First switch; 42. Second switch; 43. Third switch; 44. Fourth switch; 50. Heat dissipation module; 61. First water pump; 62. Second water pump.

Detailed ways

In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

Reference to "embodiment" in this application means that a particular feature, structure or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

The term "and/or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and/or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character "/" in this application generally indicates that the associated objects before and after are in an "or" relationship.

In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

The term "plurality" used in the present application refers to two or more (including two).

At present, with the development of new energy technology, batteries are increasingly widely used in various electrical devices, such as mobile phones, laptops, battery cars, electric cars, electric airplanes, electric ships, etc. As the application field of batteries continues to expand, the market demand is also constantly expanding.

Power batteries can be used as the main power source for electrical devices (such as vehicles, ships or spacecraft), while energy storage batteries can be used as the charging source for electrical devices. The importance of both is self-evident. As an example but not a limitation, in some application scenarios, power batteries can be batteries in electrical devices, and energy storage batteries can be batteries in charging devices. For ease of description, in the following, power batteries and energy storage batteries can be collectively referred to as battery packs or batteries.

The inventors have noticed that in the related art, in order to increase the battery temperature in a low temperature environment, it is usually necessary to specially design the motor in the electrical device. This improvement method will undoubtedly increase the difficulty of motor design and the manufacturing cost of the motor. It is also not applicable to existing electrical devices.

In order to solve the above technical problems, the embodiments of the present application provide a thermal management system, a motor control method and a vehicle. The thermal management system provided by the embodiments of the present application is first introduced below.

The thermal management system disclosed in the embodiment of the present application can be used in, but not limited to, electrical devices such as vehicles, ships, or aircraft. The embodiment of the present application provides an electrical device that uses a battery pack as a power source. The electrical device may include at least two motors, and may also include other components whose working efficiency is affected by the ambient temperature. For example, the electrical device may be, but not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, and the like.

FIG1 shows a schematic diagram of a module structure of a thermal management system provided in one embodiment of the present application. The thermal management system includes a first heat exchange circuit, a second heat exchange circuit, and a heat exchange medium.

For the convenience of description, the following embodiments are described by taking an electric vehicle as an example.

The first heat exchange circuit includes the first motor 10 and the battery pack 30, and the second heat exchange circuit includes the second motor 20 and the heat storage branch L1. When the heat storage branch L1 is connected to the second motor 20, it can store and release the heat generated by the second motor.

The heat exchange medium can flow in the first heat exchange circuit or the second heat exchange circuit. When the heat exchange medium flows in the first heat exchange circuit, it can exchange heat with the first motor 10 or the battery pack 30. When the heat exchange medium flows in the second heat exchange circuit, it can exchange heat with the second motor 20. The heat exchange medium can be water, ethylene glycol, thermal oil or other liquid heat transfer medium.

The first heat exchange circuit may also include a first medium transmission module, which can drive the heat exchange medium to circulate in the first heat exchange circuit, so that the heat exchange medium exchanges heat with each module in the first heat exchange circuit during the circulation process, thereby realizing heat transfer and transmission. The first medium transmission module may be a device for conveying liquid or a device for pressurizing liquid. By transferring external energy to the liquid, the energy of the liquid is increased, thereby realizing liquid transmission. Similarly, the second heat exchange circuit may also include a second medium transmission module, which can drive the heat exchange medium to circulate in the second heat exchange circuit, so that the heat exchange medium exchanges heat with each module in the second heat exchange circuit during the circulation process, thereby realizing heat transfer and transmission. The second medium transmission module may be a device for conveying liquid or a device for pressurizing liquid.

The first heat exchange circuit includes the first motor 10, which means that the cooling circuit of the first motor 10 is a part of the first heat exchange circuit. When the heat exchange medium flows in the first heat exchange circuit, it can flow through the cooling circuit of the first motor 10 and achieve heat exchange with the first motor 10.

The first motor 10 may be a motor of an electric device, or an electric drive assembly of an electric device including a motor. For example, the electric drive assembly may include a motor, a reducer, and an electronic control. In addition, since the electric energy conversion assembly connected to the electric drive assembly, such as an on-board charger, a voltage conversion module, a distribution box, etc., will also generate a certain amount of heat when the motor of the electric device is running, the cooling circuit of the electric energy conversion assembly may also be used as part of the first heat exchange circuit.

Similarly, the first heat exchange circuit includes the battery pack 30, which means that the cooling circuit or heating circuit of the battery pack 30 is part of the first heat exchange circuit. When the heat exchange medium flows in the first heat exchange circuit, it can flow through the cooling circuit or heating circuit of the battery pack 30 and achieve heat exchange with the battery pack 30. It can be understood that when the heat exchange medium releases heat to the battery pack 30, the circuit is the heating circuit of the battery pack 30; when the heat exchange medium absorbs heat from the battery pack 30, the circuit is the cooling circuit of the battery pack 30.

The second heat exchange circuit includes the second motor 20, which means that the cooling circuit or heating circuit of the second motor 20 is a part of the second heat exchange circuit. When the heat exchange medium flows in the second heat exchange circuit, it can flow through the cooling circuit or heating circuit of the second motor 20 and achieve heat exchange with the second motor 20. It can be understood that when the heat exchange medium releases heat to the second motor 20, the circuit is the heating circuit of the second motor 20; when the heat exchange medium absorbs heat from the second motor 20, the circuit is the cooling circuit of the second motor 20.

When the first heat exchange circuit is turned on, the heat exchange medium can flow in the first motor 10 and the heat storage branch L1. When the heat exchange medium flows to the first motor 10, it can absorb the heat generated by the first motor 10 during driving operation, and transfer the absorbed heat by flowing in the first heat exchange circuit. After the heat generated by the first motor 10 is absorbed by the heat exchange medium, when the heat exchange medium flows to the battery pack 30, the heat can be released to heat the battery pack 30 and achieve temperature increase of the battery pack 30.

When the second heat exchange circuit is turned on, the heat exchange medium can flow between the second motor 20 and the heat storage branch L1. When the heat exchange medium flows to the second motor 20, it can absorb the heat generated by the second motor 20 during driving operation, and transfer the absorbed heat by flowing in the second heat exchange circuit. After the heat generated by the second motor 20 is absorbed by the heat exchange medium, the heat exchange medium can flow back to the second motor 20 through the heat storage branch L1 in the second heat exchange circuit. Since the heat storage branch L1 in the second heat exchange circuit does not have a heat dissipation function, the heat absorbed by the heat exchange medium will not be released to the outside, but will be released when the heat exchange medium flows back to the second motor 20, and the second motor 20 will be heated by the released heat, thereby achieving the temperature increase of the second motor 20.

The thermal power loss of the first motor 10 and the second motor 20 is not consistent, that is, in the same time or at the same power, there is a difference between the heat generated by the first motor 10 and the heat generated by the second motor 20. When the first motor 10 and the battery pack 30 are connected through the first heat exchange circuit, the heat transfer and exchange can be achieved through the flow of the heat exchange medium in the first heat exchange circuit, and the heat generated by the first motor 10 is transferred to the battery pack 30 to heat the battery pack 30. In a low temperature environment, the output efficiency of the battery pack 30 is low. By heating the battery pack 30 with the heat generated by the first motor 10, the battery temperature of the battery pack 30 can be raised to a suitable temperature range, thereby improving the output efficiency of the battery pack 30. In a specific embodiment, the electrical device used in the thermal management system is an electric vehicle. By heating the battery pack 30 with the heat generated by the first motor 10, the efficiency of the battery pack 30 can be improved, thereby improving the cruising range of the entire vehicle.

When the second motor 20 is connected to the heat storage branch L1 through the second heat exchange circuit, the heat can be accumulated and released through the flow of the heat exchange medium in the second heat exchange circuit. After the heat generated by the second motor 20 is stored, it is released to the second motor 20 again, so that the components and media in the second motor 20 work in a suitable temperature range. For example, when the actual oil temperature of the lubricating oil of the second motor 20 is not in a suitable oil temperature range, it will affect the efficiency of the second motor 20. After absorbing the heat released by the second motor 20, the heat exchange medium flows back to the second motor 20 through the heat storage branch L1. Since the heat storage branch L1 does not have a heat dissipation function, the heat absorbed by the heat exchange medium from the second motor 20 will not be released to the outside, but the heat is released when the heat exchange medium flows back to the second motor 20. The second motor 20 is heated by the released heat, so that the actual oil temperature of the second motor 20 can be raised to a suitable oil temperature range, thereby improving the efficiency of the second motor 20. When the electrical device is an electric vehicle, the second motor 20 can operate in a suitable oil temperature range after storing heat through the second heat exchange circuit, thereby improving the efficiency of the second motor 20 and increasing the cruising range of the entire vehicle.

Taking an electric vehicle as an example, when an electric vehicle is provided with two motors with inconsistent thermal power losses, one of the motors can be driven to operate alone, or both motors can be driven to operate together. When higher power is required, such as in the starting stage, the two motors can be driven to operate together to provide sufficient torque and power. In normal driving, only one motor is usually required to drive the electric vehicle. Therefore, when in a low temperature environment, if the temperature of the battery pack 30 is low, affecting the efficiency of the battery pack 30, the electric vehicle can drive the first motor 10 to operate, and transfer the heat generated by the first motor 10 during operation to the battery pack 30 through the first heat exchange circuit, thereby increasing the temperature of the battery pack 30 and increasing the cruising range of the electric vehicle. When in a normal temperature environment, the electric vehicle can drive the second motor 20 to operate. At this time, if the oil temperature of the second motor 20 is low, the heat generated by the second motor 20 can be stored by turning on the second heat exchange circuit, so that the oil temperature of the second motor 20 can be increased to a suitable oil temperature range, thereby improving the efficiency of the second motor 20 and increasing the cruising range of the electric vehicle.

In this embodiment, by setting the first heat exchange circuit and the second heat exchange circuit, the heat exchange medium can flow in the first heat exchange circuit or the second heat exchange circuit and exchange heat with each module in the circuit. In a low temperature environment, when the temperature of the battery pack 30 is low, the first motor 10 can be controlled to operate, and the first heat exchange circuit can be turned on. The heat generated by the operation of the first motor 10 is absorbed by the heat exchange medium and released to the battery pack 30 to heat the battery pack 30, increase the temperature of the battery pack 30, and thus improve the output efficiency of the battery pack 30. When the temperature of the battery pack 30 is within a suitable temperature range, the second motor 20 can be controlled to operate, and the second heat exchange circuit can be turned on. The heat generated by the operation of the second motor 20 is stored by the heat exchange medium and the heat storage branch L1, so that the second motor 20 operates within a suitable temperature range and the efficiency of the second motor 20 is improved. By improving the efficiency of the battery pack 30 or the efficiency of the second motor 20, the influence of temperature factors can be reduced and the overall efficiency can be improved. When the thermal management system is applied to electric vehicles, the vehicle's cruising range can also be improved.

According to some embodiments of the present application, the thermal power loss of the first motor 10 is greater than the thermal power loss of the second motor 20 .

When the thermal power loss of the first motor 10 is greater than the thermal power loss of the second motor 20, it means that the first motor 10 has lower efficiency and higher heat dissipation than the second motor 20. In a low temperature environment, when the battery pack 30 needs to be heated to increase the battery temperature, the first motor 10 with more heat can be driven to run, and the heat generated by the first motor 10 can be transferred to the battery pack 30 through the first heat exchange circuit to increase the battery temperature. In a normal temperature environment, when the temperature of the battery pack 30 is in a suitable temperature range and the battery pack 30 does not need to be heated, the second motor 20 with higher efficiency can be driven to run. When the temperature of the battery pack 30 is low, the main factor restricting the efficiency of the electric device is the efficiency of the battery pack 30. At this time, driving the first motor 10 to run can generate enough heat to increase the temperature of the battery pack 30, thereby improving the overall efficiency of the electric device. When the temperature of the battery pack 30 is within the normal range, the main factor restricting the overall efficiency of the electric device is the efficiency of the motor. At this time, the second motor 20 with lower thermal power loss can be driven to run to improve the overall efficiency of the electric device.

In the above embodiment, when the second motor 20 is driven to operate, the actual temperature of each module in the second motor 20 can also be detected, and the heat storage of the second motor 20 can be realized by turning on the second heat exchange circuit. For example, when the oil temperature of the second motor 20 is low, the heat generated by the second motor 20 can be stored by turning on the second heat exchange circuit to heat the lubricating oil of the second motor 20, so that the actual oil temperature is within the oil temperature range, thereby further improving the working efficiency of the second motor 20.

It is understandable that if the oil temperature of the second motor 20 is already within the oil temperature range when the second motor 20 is running, then it is also possible to choose to only drive the second motor 20 to run without turning on the second heat exchange circuit.

Please refer to FIG. 2 and FIG. 3 , according to some embodiments of the present application, the first motor 10 and the second motor 20 may be located in the same motor cooling branch, or the first motor 10 and the second motor 20 may be located in different motor cooling branches, respectively.

As shown in FIG2 , when the first motor 10 and the second motor 20 are located in the same motor cooling branch, it means that the cooling circuit of the first motor 10 is connected in series with the cooling circuit of the second motor 20, and when the heat exchange medium flows through the motor cooling branch, it will flow through the first motor 10 and the second motor 20 in sequence. That is, the first heat exchange circuit actually also includes the second motor 20, and the second heat exchange circuit actually also includes the first motor 10.

When the first motor 10 and the second motor 20 are located in the same motor cooling branch, heat exchange can be achieved through the motor cooling branch regardless of whether the first motor 10 or the second motor 20 is driven to operate.

As shown in FIG3 , when the first motor 10 and the second motor 20 are located in different motor cooling branches, it means that the cooling circuit of the first motor 10 can be connected in parallel with the cooling circuit of the second motor 20. When the heat exchange medium flows through the cooling circuit of the first motor 10, it will not pass through the cooling circuit of the second motor 20; when the heat exchange medium flows through the cooling circuit of the second motor 20, it will not pass through the cooling circuit of the first motor 10.

When the first motor 10 and the second motor 20 are located in different motor cooling branches, if the first motor 10 is running, the motor cooling branch where the first motor 10 is located can be turned on, and the second motor 20 is not running at this time, and the heat exchange medium will not flow through the second motor 20 to generate heat loss. When the second motor 20 is running, the motor cooling branch where the second motor 20 is located can be turned on, and the first motor 10 is not running at this time, and the heat exchange medium will not flow through the first motor 10 to generate heat loss.

4 and 5 , according to some embodiments of the present application, the thermal management system may further include a motor cooling branch and a first switch 41. The first motor and the second motor are located in the same motor cooling branch.

The first switch 41 may include a first end, a second end and a third end, wherein the first end is connected to the motor cooling branch, the second end is connected to the battery pack 30 , and the third end is connected to the heat storage branch L1 .

As shown in FIG4 , when the first switch 41 connects the first end to the second end, the motor cooling branch forms a first heat exchange loop with the battery pack 30. At this time, the first motor 10 can be driven to run, and the heat exchange medium can flow between the first motor 10, the second motor 20 and the battery pack 30, releasing the heat generated by the first motor 10 to the battery pack 30, so as to heat the battery pack 30 and increase the battery temperature.

As shown in FIG5 , when the first switch 41 connects the first end to the third end, the motor cooling branch and the heat storage branch L1 form a second heat exchange loop. At this time, the second motor 20 can be driven to operate, and the heat exchange medium can flow between the first motor 10, the second motor 20 and the heat storage branch L1, and the heat generated by the second motor 20 is stored and then released to the second motor 20, so that the second motor 20 operates in a suitable oil temperature range, thereby improving the operating efficiency of the second motor 20.

When the second motor 20 is running, the first switch 41 can also disconnect the first end from the other ends, at which time the motor cooling branch where the second motor 20 is located is not connected to the heat storage branch L1, the second heat exchange circuit is not connected, and the heat exchange medium does not store heat for the second motor 20. That is, when the lubricating oil temperature of the second motor 20 is already in a suitable oil temperature range, the second heat exchange circuit can also be disconnected.

6 and 7 , according to some embodiments of the present application, the thermal management system may further include a motor cooling branch, a second switch 42 and a third switch 43. The first motor and the second motor are located in different motor cooling branches.

The second switch 42 may include a first end, a second end, and a third end. The first end is connected to the first motor 10 , the second end is connected to the battery pack 30 , and the third end is connected to the heat storage branch L1 .

The third switch 43 may include a first end, a second end and a third end, wherein the first end is connected to the second motor 20, the second end is connected to the battery pack 30, and the third end is connected to the heat storage branch L1.

When the first motor 10 is running, the third switch 43 can disconnect the first end from the second end and the third end, and the heat exchange medium will not flow into the second motor 20 for heat exchange. When the second motor 20 is running, the second switch 42 can disconnect the first end from the other two ends, and the heat exchange medium will not flow into the first motor 10 for heat exchange.

As shown in Fig. 6, when the second switch 42 connects the first end with the second end, the first motor 10 and the battery pack 30 can form a first heat exchange loop. As shown in Fig. 7, when the third switch 43 connects the first end with the third end, the second motor 20 and the heat storage branch L1 can form a second heat exchange loop.

It can be understood that the second switch 42 can also connect the first end with the third end to connect the first motor 10 with the heat storage branch L1; the third switch 43 can also connect the first end with the second end to connect the second motor 20 with the battery pack 30.

The thermal power loss of the first motor 10 is greater than the thermal power loss of the second motor 20, which means that the heat generated by the first motor 10 is greater than that of the second motor 20. Therefore, when one of the two motors can be selected to run alone, the first motor 10 is usually controlled to run when the temperature of the battery pack 30 is low to generate more heat; and when the temperature of the battery pack 30 is within the normal range, the second motor 20 is controlled to run to reduce the heat generation and improve the motor efficiency. However, when the first motor 10 is running, the first motor 10 can also be connected to the heat storage branch L1 to store heat for the first motor 10 through the heat storage branch L1, thereby quickly increasing the temperature of the lubricating oil in the first motor 10. Correspondingly, when the second motor 20 is running, the second motor 20 can also be connected to the battery pack 30 to heat the battery pack 30 through the heat generated by the second motor 20.

In the embodiments shown in FIG6 and FIG7, when the second motor 20 is connected to the battery pack 30, the second switch 42 needs to connect the second end with the third end. Similarly, when the first motor 10 is connected to the heat storage branch L1, the third switch 43 needs to connect the second end with the third end. That is, when the second motor 20 is connected to the battery pack 30 or the first motor 10 is connected to the heat storage branch L1, the corresponding ports of the second switch 42 and the third switch 43 need to be controlled to be turned on at the same time.

Referring to FIG. 8 , in one embodiment, the second end and the third end of the second switch 42 are connected to the heat storage branch L1 and the battery pack 30, and the second end and the third end of the third switch 43 are connected to the heat storage branch L1 and the battery pack 30. In this embodiment, when the second motor 20 is connected to the battery pack 30, the second switch 42 does not need to be turned on; when the first motor 10 is connected to the heat storage branch L1, the third switch 43 does not need to be turned on.

Please refer to FIG. 9 and FIG. 10 , according to some embodiments of the present application, the thermal management system may further include a heat dissipation module 50 .

The heat dissipation module 50 may be connected in parallel with the heat storage branch L1 , and the heat dissipation module 50 may form a third heat exchange loop when connected with the second motor 20 .

When the heat dissipation module 50 is connected to the second motor 20, the heat generated by the second motor 20 in the working state can be transmitted to the heat dissipation module 50 through the heat exchange medium, and dissipated by the heat dissipation module 50, thereby dissipating the heat generated by the second motor 20 and avoiding the temperature of the second motor 20 being too high.

According to some embodiments of the present application, the thermal management system may further include a fourth switch 44 .

The fourth switch 44 may include a first end, a second end and a third end, the first end is connected to the first motor 10 , the second end is connected to the heat storage branch L1 , and the third end is connected to the heat dissipation module 50 .

As shown in Fig. 9, when the fourth switch 44 connects the first end with the second end, the first motor 10 and the heat storage branch L1 can form a second heat exchange loop. As shown in Fig. 10, when the fourth switch 44 connects the first end with the third end, the first motor 10 and the heat dissipation module 50 can form a third heat exchange loop.

When the temperature of the second motor 20 is low, the second heat exchange circuit can be turned on, the heat storage branch L1 does not have a heat dissipation function, and the heat generated by the second motor 20 can be released to the second motor 20 through the flow of the heat exchange medium to increase the temperature of the second motor 20. When the temperature of the second motor 20 is high, the third heat exchange circuit can be turned on, and when the heat exchange medium absorbs the heat generated by the second motor 20 and flows to the heat dissipation module 50, the heat can be dissipated through the heat dissipation module 50, thereby reducing the temperature of the second motor 20.

According to some embodiments of the present application, the first switch 41 , the second switch 42 , the third switch 43 and the fourth switch 44 may be three-way proportional valves.

When the three-way proportional valve connects the ports, it can also achieve flow control of different circuits by controlling the opening of each valve. For example, through the port control of each three-way proportional valve, when the first motor 10 and the second motor 20 are running at the same time, the first motor 10 can be connected to the battery pack 30, and the second motor 20 can be connected to the heat storage branch L1. At this time, the heat generated by the first motor 10 can heat the battery pack 30, and the heat generated by the second motor 20 can be stored through the heat storage branch L1 to heat the second motor 20 itself. By adjusting the valve opening of each three-way proportional valve, the heating efficiency of the battery pack 30 and the heat storage efficiency of the second motor 20 can be further adjusted.

According to some embodiments of the present application, the first motor 10 may be an induction asynchronous motor, and the second motor 20 may be a permanent magnet synchronous motor.

Taking the electric device as an electric vehicle as an example, the electric vehicle can be provided with dual motors, which are an induction asynchronous motor and a permanent magnet synchronous motor. The efficiency of the induction asynchronous motor is lower than that of the permanent magnet synchronous motor, and the thermal power loss is higher than that of the permanent magnet synchronous motor. In a low temperature environment, when the battery pack 30 needs to be heated, the induction asynchronous motor can be controlled to operate to generate more heat, and the heat is transferred to the battery pack 30 through the first heat exchange circuit to heat the battery pack 30. In a normal temperature environment, when the battery pack 30 does not need to be heated, the permanent magnet synchronous motor can be controlled to operate to reduce heat loss, improve the efficiency of the motor assembly, and increase the vehicle's cruising range. In addition, when the permanent magnet synchronous motor is running, it can also be determined whether to conduct the second heat exchange circuit according to the temperature of the lubricating oil in the permanent magnet synchronous motor. When the oil temperature is low, the second heat exchange circuit can be used to store heat to increase the oil temperature; when the oil temperature is high, the third heat exchange circuit can be used to dissipate heat to reduce the oil temperature. By adjusting the oil temperature of the permanent magnet synchronous motor through different heat exchange circuits, the permanent magnet synchronous motor can operate in a more efficient oil temperature zone, further improving the efficiency of the motor assembly and the vehicle's range.

According to some embodiments of the present application, the first heat exchange circuit may further include a first medium transmission module, and the second heat exchange circuit may further include a second medium transmission module.

The first medium transmission module can drive the heat exchange medium to circulate in the first heat exchange circuit, so that the heat exchange medium exchanges heat with each module in the first heat exchange circuit during the circulation process, thereby realizing heat transfer and transmission. The first medium transmission module can be a device for conveying liquid or a device for pressurizing liquid. By transmitting external energy to the liquid, the liquid energy is increased, thereby realizing the transmission of the liquid.

Similarly, the second medium transmission module can drive the heat exchange medium to circulate in the second heat exchange circuit, so that the heat exchange medium exchanges heat with each module in the second heat exchange circuit during the circulation process, thereby realizing heat transfer and transmission. The second medium transmission module can also be a device for conveying liquid or a device for pressurizing liquid.

In some embodiments, the first medium transmission module may be a first water pump 61 , and the second medium transmission module may be a second water pump 62 .

The first water pump 61 may be a battery water pump, and the first water pump 61 may drive the heat exchange medium to circulate in the first heat exchange circuit.

The second water pump 62 may be a motor water pump, and the second water pump 62 may drive the heat exchange medium to circulate in the second heat exchange circuit.

In some embodiments, the second water pump 62 may also be disposed on a common branch of the second heat exchange circuit and the third heat exchange circuit. When the second heat exchange circuit is turned on, the second water pump 62 may drive the heat exchange medium to circulate in the second heat exchange circuit to store heat for the second motor 20. When the third heat exchange circuit is turned on, the second water pump 62 may drive the heat exchange medium to circulate in the third heat exchange circuit to dissipate the heat generated by the second motor 20 through the heat dissipation module 50.

The present application also provides a motor control method, which is applied to the thermal management system in the above embodiment. As shown in FIG11 , the motor control method includes:

S110, obtaining the battery temperature of the battery pack;

S120, when the battery temperature is lower than a first temperature range, controlling the first motor to operate and turning on the first heat exchange circuit;

S130: When the battery temperature is within a first temperature range, control the second motor to operate.

The motor control method in the embodiment of the present application is applied to a thermal management system, which can be provided in various electrical devices, such as battery vehicles, electric vehicles, electric aircraft, electric ships, etc. The following takes an electric vehicle as an example.

When the electric device is an electric vehicle, the electric vehicle may include a first motor, a second motor, and a battery pack. There is a difference between the thermal power loss of the first motor and the thermal power loss of the second motor, and generally the thermal power loss of the first motor is greater than the thermal power loss of the second motor. The thermal management system may construct a first heat exchange circuit between the first motor and the battery pack, and achieve heat exchange with the first motor and heat exchange with the battery pack by the flow of the heat exchange medium in the first heat exchange circuit. Similarly, the thermal management system may also construct a second heat exchange circuit in the second motor and the heat storage branch, and achieve heat exchange with the second motor by the flow of the heat exchange medium in the second heat exchange circuit.

In S110, the electric device may obtain the battery temperature of the battery pack. For example, the battery temperature may be the battery cell temperature of each battery cell in the battery pack.

In S120, after determining the battery temperature of the battery pack, a first temperature range corresponding to the battery temperature can be obtained. If the battery temperature is lower than the first temperature range, it means that the battery pack is under low temperature conditions, and the low temperature conditions will affect the output efficiency of the battery pack. That is, the battery pack is affected by the low temperature environment, resulting in reduced output efficiency, which in turn causes the range of the electric vehicle to decline.

When the battery temperature is lower than the first temperature range, the first heat exchange circuit of the thermal management system can be controlled to be turned on, and the first motor can be controlled to operate. When the first motor is in operation, it can generate more heat than the second motor. The heat exchange medium in the first heat exchange circuit can absorb the heat of the first motor in operation, and transfer the heat to the battery pack through circulation flow, so as to heat the battery pack and increase the battery temperature of the battery pack.

In S130, when the battery temperature is within the first temperature range, it means that the battery pack is at room temperature, and the temperature factor has little effect on the output efficiency of the battery pack. At this time, the main factor affecting the efficiency of the electric device is the efficiency of the motor.

When the battery temperature is within the first temperature range, the second motor can be controlled to operate. When the second motor is in operation, the heat generated is less than that of the first motor, and the operating efficiency of the second motor is higher than that of the first motor. By driving the second motor to operate, the heat generated by the motor can be reduced, the efficiency of the motor can be improved, and the efficiency of the electric device can be optimized. When the electric device is an electric vehicle, the cruising range of the entire vehicle can be improved.

When the battery temperature is higher than the first temperature range, it indicates that the battery temperature is too high. At this time, the battery pack needs to be cooled, or a temperature warning is issued to the user, so that the vehicle can drive to a safe area as soon as possible and stop running. It can be understood that in the above embodiment, the battery pack can also be connected to the heat dissipation module through each three-way proportional valve, and the heat of the battery pack is transferred to the heat dissipation module through the heat exchange medium for heat dissipation, so as to reduce the battery temperature of the battery pack.

In this embodiment, by detecting the battery temperature of the battery pack, a suitable motor can be selected and driven to operate to improve the efficiency of the electrical device. When the temperature of the battery pack is low, the first motor can be driven to operate and the first heat exchange circuit can be turned on. More heat can be generated by the first motor, and the heat can be used to heat the battery pack through the first heat exchange circuit to increase the battery temperature of the battery pack. When the temperature of the battery pack is within a suitable temperature range, the second motor can be driven to operate. The second motor generates less heat, which can reduce the thermal power loss when the motor is running and improve the efficiency of the motor. By driving different motors to operate in different environments, the battery temperature of the battery pack can be increased at low temperatures, and the thermal power loss of the motor can be reduced at normal temperatures, thereby optimizing the efficiency of the electrical device.

According to some embodiments of the present application, after the above S130, the following may also be included:

S210, obtaining the lubricating oil temperature of the second motor;

S220, when the lubricating oil temperature is lower than the second temperature range, turning on the second heat exchange circuit;

S230, when the lubricating oil temperature is higher than the second temperature range, turning on the third heat exchange circuit.

In S210, when the second motor is running, the lubricating oil temperature of the second motor can also be obtained. It is understandable that when the temperature of the lubricating oil of the second motor is too high or too low during operation, the operating efficiency of the second motor will be affected.

In S220, after obtaining the second temperature range corresponding to the second motor, the current lubricating oil temperature can be compared with the second temperature range. The second temperature range can be the oil temperature zone of the second motor. When the oil temperature is within the second temperature range, the efficiency of the second motor is higher.

If the current temperature of the lubricating oil is lower than the second temperature range, the thermal management system can turn on the second heat exchange circuit to store heat for the second motor through the heat storage branch to increase the oil temperature.

In S230, if the current temperature of the lubricating oil is higher than the second temperature range, the thermal management system can conduct the third heat exchange circuit. At this time, after absorbing the heat generated by the second motor, the heat exchange medium does not flow through the heat storage branch, but dissipates the heat through the heat dissipation module to achieve heat dissipation of the second motor. By dissipating the heat of the second motor through the third heat exchange circuit, the oil temperature of the second motor can be reduced.

In this embodiment, when the second motor is running, the corresponding heat exchange circuit can be turned on according to the actual oil temperature. When the oil temperature is low, the second motor can be stored with heat through the second heat exchange circuit; when the oil temperature is high, the second motor can be cooled with the third heat exchange circuit. By storing and cooling the second motor, the oil temperature of the second motor can be controlled within a suitable temperature range, so that the second motor maintains a high efficiency.

It should be noted that in the above embodiments, the conduction and disconnection of each heat exchange circuit and the start and stop of the first motor or the second motor can be controlled by a thermal management system, or the conduction and disconnection of each heat exchange circuit and the start and stop of the first motor or the second motor can be controlled by a vehicle controller of the electric vehicle.

An embodiment of the present application also provides a vehicle, including the thermal management system in any of the above embodiments. The vehicle may be an electric vehicle that applies the thermal management system in any of the above embodiments.

According to some embodiments of the present application, the vehicle includes a front-drive motor and a rear-drive motor, the first motor is the front-drive motor, and the second motor is the rear-drive motor. In a specific implementation, the first motor is a front-drive induction asynchronous motor, and the second motor is a rear-drive permanent magnet synchronous motor.

It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein, but these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

A thermal management system, comprising:

A first heat exchange circuit includes a first motor and a battery pack;

The second heat exchange circuit includes a second motor and a heat storage branch; the heat storage branch is used to store and release the heat generated by the second motor;

A heat exchange medium is used for performing heat exchange in the first heat exchange circuit and/or the second heat exchange circuit.
The thermal management system of claim 1, wherein a thermal power loss of the first motor is greater than a thermal power loss of the second motor.
The thermal management system according to claim 2, wherein the thermal management system further comprises:

A motor cooling branch, wherein the first motor and the second motor are located in the same motor cooling branch;

The first switch includes a first end, a second end and a third end, which are respectively connected to the motor cooling branch, the battery pack and the heat storage branch; when the first switch connects the first end with the second end, the first heat exchange circuit is formed; when the first switch connects the first end with the third end, the second heat exchange circuit is formed.
The thermal management system according to claim 2, wherein the thermal management system further comprises:

A motor cooling branch, wherein the first motor and the second motor are located in different motor cooling branches;

A second switch, comprising a first end, a second end and a third end, respectively connected to the first motor, the battery pack and the heat storage branch;

The third switch includes a first end, a second end and a third end, which are respectively connected to the second motor, the battery pack and the heat storage branch.
The thermal management system according to any one of claims 1 to 4, wherein the thermal management system further comprises:

A heat dissipation module is connected in parallel with the heat storage branch and is used to form a third heat exchange loop with the second motor.
The thermal management system according to claim 5, wherein the thermal management system further comprises:

The fourth switch includes a first end, a second end and a third end, which are respectively connected to the first motor, the heat storage branch and the heat dissipation module; when the fourth switch connects the first end with the second end, a second heat exchange circuit is formed; when the fourth switch connects the first end with the third end, a third heat exchange circuit is formed.
The thermal management system according to claim 6, wherein the first switch, the second switch, the third switch and the fourth switch are three-way proportional valves.
The thermal management system according to claim 2, wherein the first motor is an induction asynchronous motor and the second motor is a permanent magnet synchronous motor.
The thermal management system according to any one of claims 1 to 4, wherein the first heat exchange circuit further comprises a first medium transmission module, and the first medium transmission module is used to drive the heat exchange medium to circulate in the first heat exchange circuit;

The second heat exchange circuit further includes a second medium transmission module, and the second medium transmission module is used to drive the heat exchange medium to circulate in the second heat exchange circuit.
A motor control method, applied to a thermal management system according to any one of claims 1 to 9, the method comprising:

Get the battery temperature of the battery pack;

When the battery temperature is lower than a first temperature range, controlling the first motor to operate and turning on the first heat exchange circuit;

When the battery temperature is within a first temperature range, the second motor is controlled to operate.
The motor control method according to claim 10, wherein, after controlling the second motor to operate when the battery temperature is within the first temperature range, the method further comprises:

Acquiring the lubricating oil temperature of the second motor;

When the lubricating oil temperature is lower than a second temperature range, conducting the second heat exchange circuit;

When the lubricating oil temperature is higher than the second temperature range, the third heat exchange circuit is turned on.
A vehicle, comprising the thermal management system according to any one of claims 1 to 9.
The vehicle according to claim 12, wherein the first motor is a front-drive motor and the second motor is a rear-drive motor.