阅读说明：本技术 一种混合动力汽车电池包热管理控制系统及控制方法 (Thermal management control system and control method for battery pack of hybrid electric vehicle ) 是由 李明敏 丁文敏 刘淑英 段龙杨 黄炯 曾志嵘 于 2021-07-14 设计创作，主要内容包括：本发明公开了一种混合动力汽车电池包热管理控制系统及控制方法,该控制系统包括发动机冷却、空调冷媒和电池包热管理控制模块,所述发动机冷却控制模块包括依次串联的发动机水路总成、发动机水温传感器、单向阀、和换热器；空调冷媒控制模块包括依次串联的空调系统总成、电子膨胀阀和冷媒板换；电池包热管理控制模块包括依次串联的电池包内部水路总成、电子水泵、两位三通电磁阀、冷媒板换和换热器。本发明控制系统设计了中低温下的预冷却、高温下的高效换热冷却、极低温下的加热、电芯的能量均衡四种热管理控制模式,使电池包可以随着外部环境、整车负荷以及电芯温度的变化,在节能模式和高效模式下自由切换,减少了电池包的无效能耗。(The invention discloses a hybrid electric vehicle battery pack heat management control system and a control method, wherein the control system comprises an engine cooling and air conditioning refrigerant and a battery pack heat management control module, and the engine cooling control module comprises an engine waterway assembly, an engine water temperature sensor, a one-way valve and a heat exchanger which are sequentially connected in series; the air-conditioning refrigerant control module comprises an air-conditioning system assembly, an electronic expansion valve and a refrigerant plate exchanger which are sequentially connected in series; the battery pack heat management control module comprises a battery pack internal water path assembly, an electronic water pump, a two-position three-way electromagnetic valve, a refrigerant plate exchanger and a heat exchanger which are sequentially connected in series. The control system of the invention designs four heat management control modes of pre-cooling at medium and low temperature, high-efficiency heat exchange cooling at high temperature, heating at extremely low temperature and energy balance of the battery core, so that the battery pack can be freely switched between an energy-saving mode and a high-efficiency mode along with the change of external environment, the load of the whole vehicle and the temperature of the battery core, and the ineffective energy consumption of the battery pack is reduced.)

1. The utility model provides a hybrid vehicle battery package thermal management control system, includes engine cooling control module, air conditioner refrigerant control module and battery package thermal management control module, its characterized in that: the engine cooling control module comprises an engine water path assembly (9), an engine water temperature sensor (14), a one-way valve (8) and a heat exchanger (5) which are sequentially connected in series; the air-conditioning refrigerant control module comprises an air-conditioning system assembly (11), an electronic expansion valve (4) and a refrigerant plate exchanger (3) which are sequentially connected in series; the battery pack heat management control module comprises a battery pack internal water path assembly (10), an electronic water pump (1), a two-position three-way electromagnetic valve (2), a refrigerant plate exchanger (3) and a heat exchanger (5) which are sequentially connected in series;

still be connected with low temperature radiator (6) between inside water route assembly (10) of battery package and two tee bend solenoid valve (2), low temperature radiator (6) outside is provided with electronic fan (7), inside water route assembly (10) outside of battery package is provided with electric core temperature sensor (13).

2. The hybrid electric vehicle battery pack thermal management control system according to claim 1, further comprising a battery pack thermal management controller (12), wherein an input end of the battery pack thermal management controller (12) is electrically connected with the ambient temperature sensor (15), the cell temperature sensor (13) and the engine water temperature sensor (14), respectively; the output end of the whole vehicle thermal management device (12) is respectively and electrically connected with the electronic water pump (1), the two-position three-way electromagnetic valve (2), the one-way valve (8), the electronic expansion valve (4) and a sub-controller on the electronic fan (7).

3. The hybrid electric vehicle battery pack thermal management control system according to claim 1, wherein the engine water path assembly (9) comprises a water pump (19), an engine water jacket (20), a thermostat (23), an engine radiator (21) and an air-conditioning warm core (22), the water pump (19), the engine water jacket (20) and the thermostat (23) are sequentially connected in series through pipelines, and the engine radiator (21) and the air-conditioning warm core are respectively connected to two ends of the engine water jacket (20) and the thermostat (23) in parallel to form the engine water path assembly (9);

the air conditioning system assembly (11) comprises a compressor (24), a condenser (25), an evaporator (27) and an expansion valve (26) which are sequentially connected in series;

the battery pack internal waterway assembly (10) comprises a battery pack water cooling plate (28) and a battery pack (29) connected with the battery pack water cooling plate (28).

4. The hybrid electric vehicle battery pack thermal management control system according to claim 1, wherein the battery pack thermal management control module has four control loops, namely a battery pack step cooling loop, a battery pack pre-cooling loop, a battery pack heating loop and a battery pack circulating loop;

the circulation path of the battery pack pre-cooling loop is as follows: the battery pack internal waterway assembly (10), the electronic water pump (1), the two-position three-way electromagnetic valve (2) and the low-temperature radiator (6);

the circulation paths of the battery pack stepped cooling loop, the battery pack heating loop and the battery pack circulation loop are all as follows: the method comprises the following steps of (1) a battery pack internal waterway assembly (10), an electronic water pump (1), a two-position three-way electromagnetic valve (2), a refrigerant plate exchanger (3) and a heat exchanger (5);

in the battery pack circulation loop, energy exchange does not occur in the refrigerant plate exchanger (3) and the heat exchanger (5); energy exchange does not occur in the refrigerant plate exchange (3) in the battery pack heating loop, and energy exchange occurs in the heat exchanger (5); in the battery pack step cooling loop, energy exchange occurs in the refrigerant plate exchanger (3), and energy exchange does not occur in the heat exchanger (5).

5. A thermal management control method for a hybrid electric vehicle battery pack is characterized by comprising the following steps:

s1, a battery pack thermal management controller (12) reads temperature data of an engine water temperature sensor (14), a battery core temperature sensor (13) and an environment temperature sensor (15), and judges the thermal management requirement of a battery pack;

s2, according to different battery pack heat management requirements, after preset logic conversion, a battery pack heat management controller (12) sends control signals to sub-controllers on an electronic water pump (1), an electronic fan (7), a two-position three-way electromagnetic valve (2), a one-way valve (8) and an electronic expansion valve (4) respectively;

and S3, the electronic water pump (1), the electronic fan (7), the two-position three-way electromagnetic valve (2), the one-way valve (8) and a sub-controller on the electronic expansion valve (4) change the working state of the electronic water pump according to the received control signals so as to meet the thermal management requirement of the battery pack.

6. The method for controlling heat management of a battery pack of a hybrid electric vehicle according to claim 5, wherein the step S1 is performed by determining the heat management requirement of the battery pack according to the following specific determination logic:

judging that the battery pack is in a pre-cooling mode when the highest temperature of the battery pack is more than A1 and the average temperature of the battery pack is more than B1, and exiting the pre-cooling mode when the temperature of the battery pack is less than A2 or the average temperature of the battery pack is less than B2;

judging that the battery pack is in the advanced cooling mode when the highest temperature of the battery pack is more than A3 and the average temperature is more than B3, and exiting the advanced cooling mode when the temperature of the battery pack is less than A4 or the average temperature is less than B4;

thirdly, when the temperature difference of the battery pack is larger than C1, the battery pack is judged to be in the circulation mode, and when the temperature difference of the battery pack is smaller than C2, the battery pack exits the circulation mode;

judging that the battery pack is in a heating mode when the lowest temperature of the battery pack is less than A5, the average temperature is less than B5 and the water temperature of the engine is more than D1; when the lowest temperature of the battery pack is more than A6 and the average temperature is less than B6, the battery pack exits the heating mode;

and judging that the heat management requirement of the battery pack is in a no-heat management requirement mode when the conditions are not met.

7. The hybrid electric vehicle battery pack heat management control method according to claim 5, wherein in step S2, the working states of the electronic water pump (1), the electronic fan (7), the two-position three-way solenoid valve (2), the one-way valve (8) and the electronic expansion valve (4) under different battery pack heat management requirements are as follows:

firstly, when a battery pack is in a pre-cooling mode, a battery pack thermal management controller (12) controls an electronic water pump (1) to be started, a two-position three-way electromagnetic valve (2) is opened to the side A-C, a one-way valve (8) is in a closed state, and an electronic fan (7) and an electronic expansion valve (8) are in an open state;

when the battery pack is in the advanced cooling mode, the battery pack thermal management controller (12) controls the electronic water pump (1) to be started, the two-position three-way electromagnetic valve (2) is opened to the side A-B, the one-way valve (8) and the electronic fan (7) are in a closed state, and the electronic expansion valve (4) is in an open state;

when the battery pack is in a heating mode, the battery pack heat management controller (12) controls the electronic water pump (1) to be started, the two-position three-way electromagnetic valve is opened to the side A-B, the one-way valve (8) is in an open state, and the electronic fan (7) and the electronic expansion valve (4) are in a closed state;

when the battery pack is in a circulation mode, the battery pack thermal management controller (12) controls the electronic water pump (1) to be started, the two-position three-way electromagnetic valve is opened to the side A-B, and the one-way valve (8), the electronic fan (7) and the electronic expansion valve (4) are in a closed state;

when the battery pack is in a mode without heat management requirement, the battery pack heat management controller (12) controls the electronic water pump (1) to be closed, the two-position three-way electromagnetic valve is opened to the A-B side, and the one-way valve (8), the electronic fan (7) and the electronic expansion valve (4) are in a closed state.

Technical Field

The invention relates to the technical field of thermal management of a battery pack of a hybrid electric vehicle, in particular to a thermal management control system and a thermal management control method of the battery pack of the hybrid electric vehicle.

Background

Compared with the traditional vehicle, the hybrid electric vehicle is additionally provided with a battery pack, a motor and a hybrid gearbox. The power battery of the hybrid electric vehicle has small electric capacity, and the charge-discharge multiplying power of the power battery is obviously higher than that of energy batteries such as pure electric vehicles under the same working condition, so that the temperature of a battery pack core is directly and rapidly increased if the power battery is not actively cooled; and when the temperature of the battery core is too low, the impact on the output power and the electric quantity of the battery can be caused, so that the thermal management control of the power battery in a hybrid vehicle type is particularly important.

The power battery generally has two cooling modes, namely air direct cooling and liquid cooling, wherein the air direct cooling mode has the advantages of less energy consumption, low cost and easy maintenance, and the defects are obvious: the heat exchange coefficient between the cooling air and the wall surface of the battery is low, and the cooling and heating time is long and the speed is slow. Along with the requirement of hybrid vehicle models on battery cooling efficiency is higher and higher, a liquid cooling mode is adopted in a considerable part of hybrid vehicle models which are being developed by current host factories, and although the cooling efficiency of a liquid cooling system is superior to that of air cooling, the liquid cooling system also has the defects of frequent compressor starting, high energy consumption, high noise and the like.

The heating energy of the current power battery generally comes from a heating film device or an externally-added PTC, the two heating modes have the defects of high energy consumption, poor maintainability and the like, and at the moment, the water temperature of the engine is high and cannot be input into the battery pack for heating, so that the water is wasted

In view of the foregoing, there is a need for a new hybrid vehicle-type battery pack thermal management control system.

Disclosure of Invention

The invention aims to solve the technical problems and provides a thermal management control system and a control method for a battery pack of a hybrid electric vehicle, so as to solve the problems of high energy consumption and incomplete performance of a thermal management system of the existing battery pack of the hybrid electric vehicle at medium and low ambient temperatures.

In order to achieve the purpose, the invention adopts the following technical scheme:

a hybrid electric vehicle battery pack heat management control system comprises an engine cooling control module, an air conditioner refrigerant control module and a battery pack heat management control module, wherein the engine cooling control module comprises an engine water path assembly, an engine water temperature sensor, a one-way valve and a heat exchanger which are sequentially connected in series; the air-conditioning refrigerant control module comprises an air-conditioning system assembly, an electronic expansion valve and a refrigerant plate exchanger which are sequentially connected in series; the battery pack heat management control module comprises a battery pack internal waterway assembly, an electronic water pump, a two-position three-way electromagnetic valve, a refrigerant plate exchanger and a heat exchanger which are sequentially connected in series;

still be connected with the low temperature radiator between inside water route assembly of battery package and the two three-way solenoid valve, the low temperature radiator outside is provided with electronic fan, the inside water route assembly outside of battery package is provided with electric core temperature sensor.

The battery pack heat management controller is characterized by also comprising a battery pack heat management controller, wherein the input end of the battery pack heat management controller is respectively and electrically connected with an environment temperature sensor, a battery core temperature sensor and an engine water temperature sensor; and the output end of the finished automobile heat manager is respectively and electrically connected with an electronic water pump, a two-position three-way electromagnetic valve, a one-way valve, an electronic expansion valve and a sub-controller on the electronic fan.

The engine water path assembly comprises a water pump, an engine water jacket, a thermostat, an engine radiator and an air-conditioning warm core, wherein the water pump, the engine water jacket and the thermostat are sequentially connected in series through a pipeline, and the engine radiator and the air-conditioning warm core are respectively connected to two ends of the engine water jacket and the thermostat in parallel to form the engine water path assembly;

the air conditioning system assembly comprises a compressor, a condenser, an evaporator and an expansion valve which are sequentially connected in series;

the internal waterway assembly of the battery pack comprises a battery pack water-cooling plate and a battery pack connected with the battery pack water-cooling plate.

The engine water path assembly comprises an engine water jacket, a water pump, an engine radiator, a thermostat, an air-conditioning warm core and other system part assemblies which can meet the basic heat dissipation function of the engine; the air conditioning system assembly comprises a compressor, a condenser, an evaporator, an expansion valve and other system part assemblies which can meet the basic refrigeration requirement of the passenger compartment; the internal water path assembly of the battery pack refers to a system part assembly which comprises a battery pack water cooling plate and the like and can meet the heat exchange requirement of the battery pack.

The battery pack thermal management control module comprises four control loops, namely a battery pack advanced cooling loop, a battery pack pre-cooling loop, a battery pack heating loop and a battery pack circulating loop;

the circulation path of the battery pack pre-cooling loop is as follows: the battery pack comprises a battery pack internal waterway assembly, an electronic water pump, a two-position three-way electromagnetic valve and a low-temperature radiator;

the circulation paths of the battery pack stepped cooling loop, the battery pack heating loop and the battery pack circulation loop are all as follows: the method comprises the following steps of (1) battery pack internal waterway assembly, electronic water pump, two-position three-way electromagnetic valve, refrigerant plate exchange and heat exchanger;

in the battery pack circulation loop, energy exchange does not occur in the refrigerant plate exchange and the heat exchanger; energy exchange does not occur in the exchange of the refrigerant plate in the battery pack heating loop, and energy exchange occurs in the heat exchanger; and in the battery pack step cooling loop, energy exchange occurs in the refrigerant plate exchange, and energy exchange does not occur in the heat exchanger.

In the technical scheme, the electronic water pump is used for controlling the flow of the battery pack heat management loop, the two-position three-way electromagnetic valve is used for controlling the flow of cooling liquid of the battery pack loop to the low-temperature radiator or the refrigerant plate to be exchanged, the one-way valve is used for controlling the water flow of a water path of an engine through a heat exchanger, the electronic expansion valve is used for controlling the flow of the refrigerant exchanged through the refrigerant plate, and the electronic fan is used for controlling the air volume passing through the low-temperature radiator.

Furthermore, the engine cooling circuit and the battery pack heating circuit exchange heat through the heat exchanger, two paths of cooling liquid in the engine cooling circuit and the battery pack heating circuit exchange energy in the heat exchanger under the driving of temperature difference, the exchanged energy is brought into the battery pack by the battery pack heating circuit cooling liquid to heat the battery pack, and reasonable control quantity is obtained after the temperature signal data of the battery pack is read and processed by the controller and is sent to the one-way valve and a sub-controller of the electronic water pump.

Furthermore, the battery pack step cooling loop and the air conditioner refrigerant loop exchange heat through refrigerant plates, the refrigerant flow of the air conditioner refrigerant loop and the temperature difference of two cooling media in the battery pack step cooling loop drive energy exchange in the refrigerant plate exchange, the exchanged negative power is carried to the battery pack by the cooling liquid in the battery pack step cooling loop for searching books to cool the battery pack, and reasonable control quantity is obtained after the temperature signal data of the battery pack is read and processed by the controller and is sent to the compressor and a sub-controller of the electronic water pump.

A thermal management control method for a hybrid electric vehicle battery pack comprises the following steps:

s1, a battery pack thermal management controller reads temperature data of an engine water temperature sensor, a battery core temperature sensor (13) and an environment temperature sensor and judges the thermal management requirement of a battery pack;

s2, according to different battery pack heat management requirements, after preset logic conversion, a battery pack heat management controller respectively sends control signals to sub-controllers on an electronic water pump, an electronic fan, a two-position three-way electromagnetic valve, a one-way valve and an electronic expansion valve;

and S3, the electronic water pump, the electronic fan, the two-position three-way electromagnetic valve, the one-way valve and a sub-controller on the electronic expansion valve change the working state of the electronic water pump, the electronic fan, the two-position three-way electromagnetic valve, the one-way valve and the sub-controller according to the received control signals so as to meet the heat management requirement of the battery pack.

Specifically, in step S1, the logic for determining the thermal management requirement of the battery pack is as follows:

judging that the battery pack is in a pre-cooling mode when the highest temperature of the battery pack is more than A1 and the average temperature of the battery pack is more than B1, and exiting the pre-cooling mode when the temperature of the battery pack is less than A2 or the average temperature of the battery pack is less than B2;

judging that the battery pack is in the advanced cooling mode when the highest temperature of the battery pack is more than A3 and the average temperature is more than B3, and exiting the advanced cooling mode when the temperature of the battery pack is less than A4 or the average temperature is less than B4;

thirdly, when the temperature difference of the battery pack is larger than C1, the battery pack is judged to be in the circulation mode, and when the temperature difference of the battery pack is smaller than C2, the battery pack exits the circulation mode;

judging that the battery pack is in a heating mode when the lowest temperature of the battery pack is less than A5, the average temperature is less than B5 and the water temperature of the engine is more than D1; when the lowest temperature of the battery pack is more than A6 and the average temperature is less than B6, the battery pack exits the heating mode;

and judging that the heat management requirement of the battery pack is in a no-heat management requirement mode when the conditions are not met.

Specifically, in step S2, the working states of the electronic water pump, the electronic fan, the two-position three-way solenoid valve, the check valve, and the electronic expansion valve under different battery pack thermal management requirements are as follows:

when the battery pack is in a pre-cooling mode, the battery pack thermal management controller controls the electronic water pump to start, the two-position three-way electromagnetic valve is opened to the A-C side, the one-way valve is in a closed state, and the electronic fan and the electronic expansion valve are in an open state; the low-temperature radiator is communicated with a battery pack cooling water jacket, the electronic water pump drives cooling liquid to circularly radiate heat between the low-temperature radiator and the battery pack, and finally heat of the battery pack is taken away through heat exchange between natural wind and the cooling liquid in the low-temperature radiator;

when the battery pack is in the advanced cooling mode, the battery pack thermal management controller controls the electronic water pump to be started, the two-position three-way electromagnetic valve is opened to the side A-B, the one-way valve and the electronic fan are in a closed state, and the electronic expansion valve is in an open state; the low-temperature radiator is isolated from a water path inside the battery pack, the A-B side of the refrigerant plate is connected with the water cooling plate of the battery pack, the electronic water pump drives cooling liquid to take away heat from the battery pack, and the heat of the battery pack is taken away through heat exchange between the refrigerant and water in the refrigerant plate exchange;

when the battery pack is in a heating mode, the battery pack thermal management controller controls the electronic water pump to start, the two-position three-way electromagnetic valve is opened to the side A-B, the one-way valve is in an open state, and the electronic fan and the electronic expansion valve are in a closed state; at the moment, the internal water path of the battery pack is communicated with the heat exchanger and the refrigerant plate in a phase-changing manner, the engine cooling liquid flows through the heat exchanger, the energy exchange is carried out between the battery pack cooling liquid and the engine cooling liquid through the heat exchanger, finally, the temperature of the battery pack cooling liquid is increased, heat is brought into the battery pack to heat the battery core, and the temperature increase of the battery core of the battery pack is realized;

when the battery pack is in a circulation mode, the battery pack thermal management controller controls the electronic water pump to start, the two-position three-way electromagnetic valve is opened to the A-B side, and the one-way valve, the electronic fan and the electronic expansion valve are in a closed state; at the moment, the heat of the battery pack is brought from a high-temperature part to a low-temperature part through cooling liquid, so that the energy transfer and balance in the battery pack are realized, and finally, the temperature difference of the battery pack is reduced until the heat management requirement (the temperature difference is less than or equal to 2 ℃) of the battery pack is met, and the battery pack is taken out of a circulation mode;

when the battery pack is in a heat management demand-free mode, the battery pack heat management controller controls the electronic water pump to be closed, the two-position three-way electromagnetic valve is opened to the A-B side, and the one-way valve, the electronic fan and the electronic expansion valve are in a closed state; at the moment, the cooling liquid in the water path inside the battery pack is in a static state, and no energy is exchanged.

The invention has the beneficial effects that:

1. the thermal management system for the battery pack of the hybrid electric vehicle has the advantages that the used parts are high in development maturity, low in cost, strong in reliability and stable in system control;

2. the system structure does not depend on whether the battery pack comprises a heating film configuration or not, a PTC heater does not need to be externally arranged to heat the power battery, the utilization rate of the power battery pack at low temperature can be improved through the control strategy designed by the design, the power experience of customers is improved, the battery pack is heated by utilizing waste heat of an engine, and the energy consumption of the whole vehicle is reduced;

3. the control strategy fully considers the phenomenon of invalid energy consumption of the battery pack heat management system, and accurately controls the rotating speed of an electronic fan, the rotating speed of an electronic water pump, the opening of a one-way valve, the opening and closing of an electronic expansion valve and the valve switch of a two-position three-way electromagnetic valve by accurately judging the heat management requirement of the battery pack, so that the occurrence of invalid energy consumption is reduced as much as possible;

4. the power battery thermal management control system mainly controls a water path or sub-control thereof through a whole vehicle thermal management control system, and the control strategy can control the water temperature at the inlet of the battery pack and the highest/lowest temperature of the battery cell so as to stably maintain the temperature difference of the battery pack within a proper range;

5. the battery pack thermal management control strategy of the present invention takes into account both the comfort of the passenger compartment and the warm-up requirements during the cold start phase of the engine.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic diagram of a thermal management system for a battery pack of a hybrid electric vehicle according to the present invention;

FIG. 2 is a schematic diagram of a connection structure of a waterway assembly of the engine according to the embodiment of the present invention;

FIG. 3 is a schematic view of a connection structure of an air conditioning system assembly according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a connection structure of a waterway assembly inside a battery pack according to an embodiment of the present invention;

fig. 5 is a flowchart of a control strategy in five battery pack thermal management modes according to an embodiment of the present invention.

The reference numerals in the figures illustrate: 1. an electronic water pump; 2. a two-position three-way electromagnetic valve; 3. exchanging a refrigerant plate; 4. an electronic expansion valve; 5. a heat exchanger; 6. a low temperature heat sink; 7. an electronic fan; 8. a one-way valve; 9. an engine water circuit assembly; 10. a waterway assembly inside the battery pack; 11. an air conditioning system assembly; 12. a battery pack thermal management controller; 13. a cell temperature sensor; 14. an engine water temperature sensor; 15. an ambient temperature sensor; 16. an air conditioning refrigerant circuit; 17. a battery pack thermal management loop; 18. an engine cooling circuit; 19. a water pump; 20. an engine water jacket; 21. an engine radiator; 22. an air-conditioning heating core; 23. a thermostat; 24. a compressor; 25. a condenser; 26. an expansion valve; 27. an evaporator; 28. the battery wraps the water cooling plate; 29. a battery pack.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without any inventive step, are within the scope of the present invention.

Example (b): see fig. 1-5.

As shown in fig. 1, a hybrid electric vehicle battery pack thermal management control system comprises an engine cooling control module, an air conditioner refrigerant control module and a battery pack thermal management control module, wherein the engine cooling control module comprises an engine waterway assembly 9, an engine water temperature sensor 14, a check valve 8 and a heat exchanger 5 which are sequentially connected in series; the air-conditioning refrigerant control module comprises an air-conditioning system assembly 11, an electronic expansion valve 4 and a refrigerant plate exchanger 3 which are sequentially connected in series; the battery pack heat management control module comprises a battery pack internal waterway assembly 10, an electronic water pump 1, a two-position three-way electromagnetic valve 2, a refrigerant plate exchanger 3 and a heat exchanger 5 which are sequentially connected in series;

still be connected with low temperature radiator 6 between battery package inside water route assembly 10 and two three-way solenoid valve 2, low temperature radiator 6 outside is provided with electronic fan 7, battery package inside water route assembly 10 outside is provided with electric core temperature sensor 13.

Specifically, in the battery pack thermal management circuit 17 described in this embodiment, one end of the battery pack internal waterway assembly 10 is connected to the inlet of the electronic water pump 1, and the other end is connected to the port B of the heat exchanger 5, the port a of the two-position three-way electromagnetic valve 2 is connected to the outlet of the electronic water pump 1, the port B of the two-position three-way electromagnetic valve 2 is connected to the port a of the refrigerant plate exchanger 3, the port B of the refrigerant plate exchanger 3 is connected to the port a of the heat exchanger 5, the inlet of the low-temperature radiator 6 is connected to the port C of the two-position three-way electromagnetic valve 2, and the outlet of the low-temperature radiator 6 is connected to the inlet of the battery pack internal waterway assembly 10; in an air-conditioning refrigerant loop 16, a port C of a refrigerant plate exchanger 3 is connected with an inlet of an air-conditioning system assembly 11, a port D of the refrigerant plate exchanger 3 is connected with an outlet of an electronic expansion valve 4, and an outlet of the air-conditioning system assembly 11 is connected with an inlet of the electronic expansion valve 4; in the engine cooling loop 18, one end of the engine water path assembly 9 is connected with the inlet of the check valve 8, the other end of the engine water path assembly is connected with the D port of the heat exchanger 5, and the C port of the heat exchanger 5 is connected with the outlet of the check valve 8.

The system also comprises a battery pack thermal management controller 12, wherein the input end of the battery pack thermal management controller 12 is respectively and electrically connected with an environment temperature sensor 15, a cell temperature sensor 13 and an engine water temperature sensor 14; the output end of the finished automobile heat management device 12 is respectively and electrically connected with the electronic water pump 1, the two-position three-way electromagnetic valve 2, the one-way valve 8, the electronic expansion valve 4 and a sub-controller on the electronic fan 7, the battery pack heat management controller 12 directly sends control instructions to the sub-controllers of the above components, and the control state conversion of each component is completed by the sub-controllers.

Specifically, the electronic water pump 1 is used for controlling the flow rate of the cooling liquid of the battery pack heat management circuit 17, the two-position three-way electromagnetic valve 2 is used for controlling the flow direction of the cooling liquid of the battery pack heat management circuit 17, the check valve 8 is used for controlling the flow rate of the cooling liquid of the engine cooling circuit 18 passing through the heat exchanger 5, the electronic expansion valve 4 is used for controlling the flow rate of the cooling medium passing through a port D to a port C in the cooling medium plate 4, and the electronic fan 7 is used for controlling the air volume passing through the low-temperature radiator 6.

As shown in fig. 2, the engine water path assembly 9 includes a water pump 19, an engine water jacket 20, a thermostat 23, an engine radiator 21 and an air-conditioning warm core 22, the water pump 19, the engine water jacket 20 and the thermostat 23 are sequentially connected in series through a pipeline, and the engine radiator 21 and the air-conditioning warm core are respectively connected in parallel to two ends of the engine water jacket 20 and the thermostat 23 to form the engine water path assembly 9;

as shown in fig. 3, the air conditioning system assembly 11 includes a compressor 24, a condenser 25, an evaporator 27, and an expansion valve 26 connected in series;

as shown in fig. 4, the battery pack internal waterway assembly 10 includes a battery pack water-cooling plate 28 and a battery pack 29 connected to the battery pack water-cooling plate 28.

It should be noted that, in this embodiment, the engine water path assembly refers to a system component assembly that includes the water pump 19, the engine water jacket 20, the thermostat 23, the engine radiator 21, the air-conditioning warm core 22, and the like, and can satisfy the basic heat dissipation function of the engine; the air conditioning system assembly comprises a compressor 24, a condenser 25, an evaporator 27, an expansion valve 26 and other system part assemblies which can meet the basic refrigeration requirement of a passenger compartment; the battery pack internal waterway assembly comprises a battery pack water cooling plate 28 and other system part assemblies capable of meeting the heat exchange requirements of the battery pack.

The battery pack thermal management control module comprises four control loops, namely a battery pack advanced cooling loop, a battery pack pre-cooling loop, a battery pack heating loop and a battery pack circulating loop;

the circulation path of the battery pack pre-cooling loop is as follows: the battery pack internal waterway assembly comprises a battery pack internal waterway assembly 10, an electronic water pump 1, a two-position three-way electromagnetic valve 2 and a low-temperature radiator 6;

the circulation paths of the battery pack stepped cooling loop, the battery pack heating loop and the battery pack circulation loop are all as follows: the method comprises the following steps of (1) a battery pack internal waterway assembly 10, an electronic water pump 1, a two-position three-way electromagnetic valve 2, a refrigerant plate exchange 3 and a heat exchanger 5;

the battery pack advanced cooling loop, the battery pack heating loop and the battery pack circulating loop are the same in series connection part, and the main difference is that: in the battery pack circulation loop, energy exchange does not occur in the refrigerant plate exchanger 3 and the heat exchanger 5; energy exchange does not occur in the refrigerant plate exchange 3 in the battery pack heating loop, and energy exchange occurs in the heat exchanger 5; in the battery pack step cooling loop, energy exchange occurs in the refrigerant plate exchanger 3, and energy exchange does not occur in the heat exchanger 5.

As shown in fig. 5, a thermal management control method for a hybrid vehicle battery pack includes the following steps:

s1, a battery pack thermal management controller 12 reads temperature data of an engine water temperature sensor 14, a battery core temperature sensor 13 and an environment temperature sensor 15, and thermal management requirements of a battery pack are judged;

s2, according to different battery pack heat management requirements, after preset logic conversion, a battery pack heat management controller 12 sends control signals to sub-controllers on the electronic water pump 1, the electronic fan 7, the two-position three-way electromagnetic valve 2, the one-way valve 8 and the electronic expansion valve 4 respectively;

and S3, the electronic water pump 1, the electronic fan 7, the two-position three-way electromagnetic valve 2, the one-way valve 8 and the sub-controllers on the electronic expansion valve 4 change the working states thereof according to the received control signals so as to meet the heat management requirement of the battery pack.

Specifically, in step S1, the logic for determining the thermal management requirement of the battery pack is as follows:

judging that the battery pack is in a pre-cooling mode when the highest temperature of the battery pack is more than A1 and the average temperature of the battery pack is more than B1, and exiting the pre-cooling mode when the temperature of the battery pack is less than A2 or the average temperature of the battery pack is less than B2;

judging that the battery pack is in the advanced cooling mode when the highest temperature of the battery pack is more than A3 and the average temperature is more than B3, and exiting the advanced cooling mode when the temperature of the battery pack is less than A4 or the average temperature is less than B4;

thirdly, when the temperature difference of the battery pack is larger than C1, the battery pack is judged to be in the circulation mode, and when the temperature difference of the battery pack is smaller than C2, the battery pack exits the circulation mode;

judging that the battery pack is in a heating mode when the lowest temperature of the battery pack is less than A5, the average temperature is less than B5 and the water temperature of the engine is more than D1; when the lowest temperature of the battery pack is more than A6 and the average temperature is less than B6, the battery pack exits the heating mode;

and judging that the heat management requirement of the battery pack is in a no-heat management requirement mode when the conditions are not met.

Specifically, in step S2, the operating states of the electronic water pump 1, the electronic fan 7, the two-position three-way solenoid valve 2, the check valve 8, and the electronic expansion valve 4 under different requirements of the thermal management of the battery pack are as follows:

firstly, when the battery pack is in a pre-cooling mode, the battery pack thermal management controller 12 controls the electronic water pump 1 to be started, the two-position three-way electromagnetic valve 2 is opened to the side A-C, the one-way valve 8 is in a closed state, and the electronic fan 7 and the electronic expansion valve 8 are in an open state; the low-temperature radiator 6 is communicated with the water cooling plate 28 of the battery pack, the electronic water pump 1 drives cooling liquid to circularly radiate heat between the low-temperature radiator 6 and the battery pack, and finally heat exchange is carried out between natural wind and the cooling liquid in the low-temperature radiator 6 to take away heat of the battery pack;

when the battery pack is in the advanced cooling mode, the battery pack thermal management controller 12 controls the electronic water pump 1 to be started, the two-position three-way electromagnetic valve 2 is opened to the side A-B, the one-way valve 8 and the electronic fan 7 are in a closed state, and the electronic expansion valve 4 is in an open state; at the moment, the low-temperature radiator 6 is isolated from a water channel inside the battery pack, the A-B side of the refrigerant plate is connected with the water cooling plate 28 of the battery pack, the electronic water pump 1 drives cooling liquid to take away heat from the battery pack, and heat exchange is carried out between the refrigerant and water in the refrigerant plate exchanger 3 to take away the heat of the battery pack;

when the battery pack is in a heating mode, the battery pack thermal management controller 12 controls the electronic water pump 1 to be started, the two-position three-way electromagnetic valve is opened to the side A-B, the one-way valve 8 is in an opening state, and the electronic fan 7 and the electronic expansion valve 4 are in a closing state; at the moment, an internal water path of the battery pack is communicated with the heat exchanger 5 and the refrigerant plate exchanger 3, the engine cooling liquid flows through the heat exchanger 5, the energy exchange is carried out between the battery pack cooling liquid and the engine cooling liquid through the heat exchanger 5, finally, the temperature of the battery pack cooling liquid is increased, heat is brought into the battery pack to heat the battery core, and the temperature of the battery core of the battery pack is increased;

when the battery pack is in a circulation mode, the battery pack thermal management controller 12 controls the electronic water pump 1 to be started, the two-position three-way electromagnetic valve is opened to the side A-B, and the one-way valve 8, the electronic fan 7 and the electronic expansion valve 4 are in a closed state; at the moment, the heat of the battery pack is brought from the high-temperature part to the low-temperature part through cooling liquid, so that the energy transfer and balance in the battery pack are realized, and finally, the temperature difference of the battery pack is reduced until the temperature difference meeting the heat management requirement of the battery pack is less than or equal to 2 ℃, and then the battery pack is taken out of a circulation mode;

when the battery pack is in a mode without heat management requirement, the battery pack heat management controller 12 controls the electronic water pump 1 to be closed, the two-position three-way electromagnetic valve is opened to the A-B side, and the one-way valve 8, the electronic fan 7 and the electronic expansion valve 4 are in a closed state; at the moment, the cooling liquid in the water path inside the battery pack is in a static state, and no energy is exchanged.

In conclusion, the hybrid electric vehicle battery pack thermal management control system of the invention designs four thermal management control modes for the power battery, namely 1 low-temperature radiator 6 pre-cooling mode at medium and low temperature; 2. The refrigerant plate exchange 3 at high temperature is in a high-efficiency heat exchange cooling mode; 3. heating mode of engine waste heat at extremely low temperature to the battery pack; 4. a self-circulation energy balance mode under the condition of large temperature difference of the battery core; the four thermal management modes can be switched at any time through the battery pack thermal management controller 12 along with changes of external environments, load of the whole vehicle and temperature of a battery cell, and a brand-new control system and a brand-new control strategy are provided for thermal management of the hybrid vehicle type power battery.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.