US-20260124878-A1 - THERMAL MANAGEMENT SYSTEM, CONTROL METHOD THEREFOR, AND VEHICLE

Abstract

A control method for a thermal management system comprising receiving a battery heating signal at the thermal management system including at least one heat exchange branch configured to exchange heat with a battery, and entering, by the thermal management system, a preheating mode. A temperature of a heat exchange medium at an outlet end of the at least one heat exchange branch is greater than or equal to a first threshold T 1.

Inventors

• Heping Ling
• Wei Huang
• Rui Ma
• Feng LAI
• Yili LUO

Assignees

• BYD COMPANY LIMITED

Dates

Publication Date

20260507

Application Date

20251229

Priority Date

20230703

Claims (20)

1. 1 . A control method for a thermal management system, comprising: receiving a battery heating signal at the thermal management system including at least one heat exchange branch configured to exchange heat with a battery; and entering, by the thermal management system, a preheating mode, wherein a temperature of a heat exchange medium at an outlet end of the at least one heat exchange branch is greater than or equal to a first threshold T 1 .
2. 2 . The control method according to claim 1 , wherein a temperature difference ΔT between a temperature of the heat exchange medium at an inlet end of the at least one heat exchange branch and the temperature at the outlet end is less than or equal to a second threshold T 2 .
3. 3 . The control method according to claim 1 , wherein the thermal management system enters a normal heating mode when a temperature of the battery reaches a first temperature, and in the normal heating mode, at least one of the at least one heat exchange branch is controlled, based on a real-time temperature of the battery, to be turned on to heat the battery.
4. 4 . The control method according to claim 3 , wherein the thermal management system comprises a battery subsystem that comprises a plurality of heat exchange branches arranged in parallel, and the plurality of heat exchange branches are configured to exchange heat with the battery and comprise a pressure adjustment sub-branch; and in the preheating mode, a temperature of a heat exchange medium at an outlet end of the pressure adjustment sub-branch is controlled to be greater than or equal to the first threshold T 1 .
5. 5 . The control method according to claim 4 , wherein in the preheating mode, a temperature difference ΔT between an inlet end and the outlet end of the pressure adjustment sub-branch is controlled to be less than or equal to T 2 .
6. 6 . The control method according to claim 4 , wherein at least one heat exchange branch is configured to exchange heat with a first side of the battery, and at least one heat exchange branch is configured to exchange heat with a second side of the battery.
7. 7 . The control method according to any one of claim 4 , wherein the plurality of heat exchange branches comprise the pressure adjustment sub-branch and a heat exchange sub-branch; and in the preheating mode, a total flow Q 1 in the pressure adjustment sub-branch is greater than a total flow Q 2 in the heat exchange sub-branch.
8. 8 . The control method according to claim 7 , wherein in the preheating mode, a ratio Q 1 /Q 2 of the total flow Q 1 of heat exchange media in the pressure adjustment sub-branch to the total flow Q 2 in the heat exchange sub-branch is greater than a third threshold.
9. 9 . The control method according to claim 7 , wherein the plurality of heat exchange branches comprise the pressure adjustment sub-branch and the heat exchange sub-branch, and at least some of the heat exchange branches each comprise a flow regulating valve; and an opening degree of a valve in the pressure adjustment sub-branch is controlled to be greater than an opening degree of a valve in the heat exchange sub-branch.
10. 10 . The control method according to claim 4 , wherein the plurality of heat exchange branches comprise the pressure adjustment sub-branch and a heat exchange sub-branch; and in the preheating mode, the heat exchange sub-branch is controlled to be in a non-operating state.
11. 11 . The control method according to claim 3 , wherein when a minimum value of temperature values at a plurality of positions of the battery reaches a first specified temperature, the temperature of the battery reaches the first temperature.
12. 12 . The control method according to claim 1 , wherein the thermal management system has a normal heating mode, the heat exchange branch comprises a pressure adjustment sub-branch, and a flow in the pressure adjustment sub-branch in the preheating mode is greater than a flow in the pressure adjustment sub-branch in the normal heating mode.
13. 13 . The control method according to claim 1 , wherein the heat exchange branch comprises a battery heat exchange module and a throttle element that are connected in series; and an opening degree of the throttle element is adjusted based on a superheating degree of a heat exchange medium in the heat exchange branch.
14. 14 . The control method according to claim 13 , wherein in the preheating mode, an opening degree of the throttle element is adjusted based on a superheating degree of a heat exchange medium in the heat exchange branch, and the control method comprises: decreasing the opening degree of the throttle element when the superheating degree ΔT 4 is less than a first specified value ΔTa; increasing the opening degree of the throttle element when the superheating degree ΔT 4 is greater than a second specified value ΔTb; or maintaining the opening degree of the throttle element when the superheating degree ΔT 4 is greater than or equal to ΔTa and less than or equal to ΔTb.
15. 15 . The control method according to claim 2 , wherein the at least one heat exchange branch comprises a bottom heat exchange branch and a top heat exchange branch, the top heat exchange branch is located at a top of the battery, and the bottom heat exchange branch is located at a bottom of the battery; and in the preheating mode, a temperature difference ΔT between an inlet end and an outlet end of the bottom heat exchange branch is controlled to be less than the second threshold.
16. 16 . The control method according to claim 1 , wherein the thermal management system further comprises a coolant subsystem; and the control method further comprises: in response to a waste heat recovery instruction is received, exchanging, by the coolant subsystem, heat with the battery subsystem.
17. 17 . The control method according to claim 16 , wherein the thermal management system has a normal heating mode, and in the normal heating mode, a plurality of heat exchange branches are controlled to heat the battery; and the thermal management system enters the normal heating mode when a water temperature of a coolant subsystem reaches a third specified temperature.
18. 18 . A thermal management system, comprising: a compressor having an air inlet and an air outlet; at least one heat exchange branch exchanging heat with a battery, a first end of one of the at least one heat exchange branch being connected to the air outlet; a first heat exchanger, a first end of the first heat exchanger being connected to a second end of the heat exchange branch through a throttle element, and a second end of the first heat exchanger being connected to the air inlet; and a control module configured to: receive a battery heating signal, and cause the thermal management system to enter a preheating mode, wherein a temperature of a heat exchange medium at an outlet end of the at least one heat exchange branch is greater than or equal to a first threshold T 1 .
19. 19 . A vehicle, comprising a thermal management system that includes a control module and at least one heat exchange branch configured to exchange heat with a battery, the control module being configured to perform a method comprising: receiving a battery heating signal; and causing the thermal management system to enter a preheating mode, wherein a temperature of a heat exchange medium at an outlet end of the at least one heat exchange branch is greater than or equal to a first threshold T 1 .
20. 20 . The vehicle according to claim 19 , wherein the control module comprises a storage medium, the storage medium is configured to store executable instructions, and the instructions, when executed, cause the control module to perform the method.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of International Application No. PCT/CN2024/103257, filed on Jul. 3, 2024, which claims priorities to Chinese Patent Applications Nos. 202310810600.3 and 202311129155.0, filed on Jul. 3, 2023, and Aug. 31, 2023, respectively. The disclosures of the prior applications are incorporated herein by reference in their entirety. TECHNICAL FIELD This application relates to the field of vehicle technologies, and to a thermal management system and a control method therefor and a vehicle. BACKGROUND A gaseous refrigerant discharged by a compressor is applied to battery heating in a vehicle to exchange heat with a battery. When the battery is heated, the gaseous refrigerant is cooled, depressurized, and liquefied. When a temperature of a battery is low, a heat exchange area of battery heat exchange is large, or a flow resistance of a battery heat exchange module is large, a heat exchange medium excessively exchanges heat in the battery heat exchange module, causing low intake pressure and low discharge pressure (low high-side pressure) of a compressor, which are beyond a running range of the compressor, and may cause damage to the compressor. SUMMARY Aspects of the disclosure provide a control method for a thermal management system. The method includes receiving a battery heating signal at the thermal management system including at least one heat exchange branch configured to exchange heat with a battery, and entering, by the thermal management system, a preheating mode. A temperature of a heat exchange medium at an outlet end of the at least one heat exchange branch is greater than or equal to a first threshold T1. Aspects of the disclosure provide a thermal management system. The thermal management system includes a compressor having an air inlet and an air outlet, at least one heat exchange branch exchanging heat with a battery. A first end of one of the at least one heat exchange branch is connected to the air outlet. The thermal management system further includes a first heat exchanger. A first end of the first heat exchanger is connected to a second end of the heat exchange branch through a throttle element, and a second end of the first heat exchanger is connected to the air inlet. The thermal management system further includes a control module. The control module is configured to receive a battery heating signal, and cause the thermal management system to enter a preheating mode. A temperature of a heat exchange medium at an outlet end of the at least one heat exchange branch is greater than or equal to a first threshold T1. Aspects of the disclosure provide a vehicle. The vehicle includes a thermal management system that includes a control module and at least one heat exchange branch. The at least one heat exchange branch is configured to exchange heat with a battery. The control module is configured to perform a method. The method includes receiving a battery heating signal, and causing the thermal management system to enter a preheating mode. A temperature of a heat exchange medium at an outlet end of the at least one heat exchange branch is greater than or equal to a first threshold T1. BRIEF DESCRIPTION OF DRAWINGS The foregoing and/or additional aspects and advantages of this application are clear and easily understood from the descriptions of the embodiments provided in conjunction with the following drawings, where: FIG. 1 is a flowchart of a control method for a thermal management system according to some embodiments of this application; FIG. 2 is a diagram of a structure of a thermal management system according to an embodiment of this application; FIG. 3 is a diagram of a structure of a thermal management system in a battery heating mode according to an embodiment of this application, where an arrow in the figure shows a refrigerant flow direction; FIG. 4 is a flowchart of a control method for a thermal management system according to some other embodiments of this application; FIG. 5 is a diagram of a structure of a battery heat exchange module according to some embodiments of this application; and FIG. 6 is a diagram of a structure of a battery heat exchange module according to some other embodiments of this application. DESCRIPTION OF EMBODIMENTS The following describes in detail embodiments of this application, and examples of the embodiments are shown in the accompanying drawings. Same or similar reference numerals throughout the accompanying drawings indicate same or similar elements or elements having same or similar functions. The following embodiments described with reference to the accompanying drawings are examples and are merely intended to explain this application, but should not be understood as a limitation on this application. The following describes a control method for a thermal management system according to an embodiment of this application with reference to the accompanying drawings. As shown in FIG. 3, a