Hybrid battery energy management system and control method

Abstract

The application discloses a kind of hybrid battery energy management systems, including engine ECU, engine, motor, BMS unit, power battery, battery temperature sensor, for the PTC heater and molten salt heat exchange structure of power battery heating and cooling liquid heat exchanger;Motor is connected with PTC heater, cooling liquid heat exchanger is associated with the exhaust pipe of engine and is set, molten salt heat exchange structure includes associated molten salt storage plate and molten salt heat exchanger, molten salt storage plate and the exhaust pipe of engine are associated with setting.Can utilize engine idling to drive motor to make the temperature of PTC heater on power battery rapidly rise, utilize engine exhaust to heat power battery by molten salt heat exchanger and cooling liquid heat exchanger further shorten power battery heating time, by exhaust heat is stored in molten salt storage plate so as to use next time cold start or cold charging;It can be used in multiple forms to heat power battery, ensure power battery operating temperature.

Description

Technical Field

[0001] This invention relates to the field of hybrid power technology, and in particular to a hybrid power battery energy management system and control method. Background Technology

[0002] Hybrid electric vehicles have a very broad prospect and have good energy-saving and emission-reduction effects. Hybrid electric vehicles use an engine and a power battery to drive together, and like fuel hybrid vehicles, they can select different power outputs according to different driving conditions.

[0003] Hybrid electric vehicles are equipped with power batteries, and therefore still face the problem of significant range reduction due to battery capacity degradation at low temperatures. Although major automakers have added various power battery heating functions, such as heat pump heating, thermal film heating, and PTC heating, the high energy consumption during battery charging remains a concern. For example, Chinese patent CN113119688B discloses a vehicle thermal management system and control method for a plug-in hybrid electric vehicle. This system utilizes at least one of the following methods to heat the power battery: a stalled motor or an engine idling, to ensure rapid heating of the power battery in low-temperature environments, thereby shortening charging time and improving the overall low-temperature driving experience. Although it utilizes engine idling and motor heat to heat the battery, the heating effect is slow and cannot rapidly raise the battery temperature in low ambient temperatures. Another example is a waste heat recovery device for natural gas vehicle exhaust gas disclosed in Chinese patent CN114658519A. This device only utilizes exhaust gas heating, without considering that engine idling can drive other devices to heat the engine. Furthermore, the thermal efficiency of the exhaust gas is not effectively preserved, and the battery cells can only be heated when the engine is running. Hybrid vehicles typically require long operating hours, placing high demands on the lifespan of their power batteries. Failure to ensure the power batteries operate at reasonable temperatures means that the power batteries are not adequately protected. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a hybrid power battery energy management system and control method, which can employ various methods to heat the power battery, ensuring its operating temperature, extending its lifespan, and with relatively low energy consumption.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0006] A hybrid power battery energy management system includes an engine ECU, an engine, an electric motor, a battery management system (BMS) unit, a power battery, and a battery temperature sensor. The engine ECU and the battery temperature sensor are both connected to the BMS unit. The system also includes a PTC heater for heating the power battery, a molten salt heat exchange structure, and a coolant heat exchanger. The electric motor is connected to the PTC heater, and the coolant heat exchanger is associated with the engine's exhaust pipe. The molten salt heat exchange structure includes an associated molten salt storage plate and a molten salt heat exchanger, and the molten salt storage plate is associated with the engine's exhaust pipe.

[0007] A solenoid valve is provided between the motor and the PTC heater.

[0008] The power battery is equipped with a battery performance testing unit, which is connected to the BMS unit.

[0009] It also includes a coolant circulation power pump, a coolant storage tank, and a waste heat circulation power pump. The coolant circulation power pump, coolant storage tank, coolant heat exchanger, and power battery form a coolant heating system. The waste heat circulation power pump is connected to the coolant heat exchanger, and a coolant heat exchange valve is provided between the waste heat circulation power pump and the coolant heat exchanger.

[0010] The molten salt heat exchange structure also includes a molten salt storage tank, in which a molten salt storage plate is stored. A waste heat circulation power pump is connected to the molten salt heat exchanger. The molten salt storage tank is provided with a drive structure for driving the molten salt storage plate to extend out of the molten salt storage tank and contact the exhaust pipe or to push it into the molten salt heat exchanger.

[0011] The drive structure includes a transverse guide rail and an electric push rod structure. The electric push rod structure includes an electric telescopic rod I for pushing the molten salt storage plate into contact with the exhaust pipe and an electric telescopic rod II for pushing the molten salt storage plate along the guide rail into the molten salt heat exchanger.

[0012] The bottom of the molten salt storage tank and the side near the molten salt heat exchanger are provided with slots for the molten salt storage plate to enter and exit. The exhaust pipe of the engine is connected to the molten salt heat exchanger through a solenoid valve.

[0013] The waste heat circulation power pump, coolant circulation power pump, and electric telescopic rod are driven by an electric motor or the vehicle's battery.

[0014] A control method for a hybrid battery energy management system is as follows: when the ambient temperature is too low, the battery pack temperature is lower than the set high-efficiency zone operating value when the car is started. The engine idle speed drives the motor to make the PTC heater on the power battery rise rapidly, and / or the engine exhaust gas is used to heat the power battery through the molten salt heat exchanger and the coolant heat exchanger to further shorten the power battery heating time. The heat is stored in the molten salt storage plate by the exhaust gas for use during the next cold start or cold charging.

[0015] In the control method, when the vehicle travels for too long, the battery performance detection unit can identify the fault threshold set by the current battery pack. If the failure rate of the battery pack exceeds the fault threshold after working for a long time, the battery performance detection unit sends a signal to the BMS and engine control unit to force the battery pack to rest, and the engine will complete the vehicle's driving needs.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] The hybrid battery energy management system and control method are rationally designed. They can use the engine idling speed to drive the motor, which can rapidly raise the temperature of the PTC heater on the power battery. The engine exhaust gas can also be used to heat the power battery through the molten salt heat exchanger and the coolant heat exchanger, further shortening the power battery heating time. By storing the heat from the exhaust gas in the molten salt storage plate, the heat can be used to heat the power battery during the next cold start or cold charging by the waste heat circulation power pump. It can use multiple forms to heat the power battery, ensuring the power battery operating temperature, extending the battery life, and with relatively low energy consumption. Attached Figure Description

[0018] The following is a brief explanation of the contents of each of the accompanying drawings and the markings in the drawings:

[0019] Figure 1 This is a schematic diagram of the system of the present invention.

[0020] In the picture:

[0021] 1-Engine ECU, 2-Engine, 3-Motor, 4-Battery temperature sensor, 5-Solenoid valve I, 6-Battery performance detection unit, 7-BMS unit, 8-PTC heater, 9-Power battery, 10-Coolant power pump, 11-Coolant storage tank, 12-Coolant heat exchanger, 13-Coolant heat exchange valve I, 14-Coolant heat exchange valve II, 15-Exhaust gas waste heat circulation power pump, 16-Solenoid valve II, 17-Molten salt heat exchanger, 18-Molten salt storage plate, 19-Molten salt storage tank, 20-Electric telescopic rod I, 21-Insulation layer, 22-Electric telescopic rod II, 23-Engine exhaust pipe, 24-Molten salt temperature sensor, 25-Solenoid valve III. Detailed Implementation

[0022] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and through the description of the examples.

[0023] like Figure 1 As shown, the hybrid battery energy management system includes an engine ECU 1, an engine 2, an electric motor 3, a BMS unit 7, a power battery 9, a battery temperature sensor 4, a PTC heater 8 for heating the power battery, a molten salt heat exchange structure, and a coolant heat exchanger 12. The engine ECU and the battery temperature sensor are both connected to the BMS unit, the electric motor is connected to the PTC heater, the coolant heat exchanger is associated with the engine's exhaust pipe, and the molten salt heat exchange structure includes an associated molten salt storage plate 18 and a molten salt heat exchanger 17. The molten salt storage plate is associated with the engine's exhaust pipe.

[0024] The system also includes a coolant circulation power pump 10, a coolant storage tank 11, and a waste heat circulation power pump 15. The coolant circulation power pump, coolant storage tank, coolant heat exchanger, and power battery form a coolant heating system. The waste heat circulation power pump is connected to the coolant heat exchanger, and a coolant heat exchange valve is provided between the waste heat circulation power pump and the coolant heat exchanger.

[0025] A molten salt heat exchanger, a waste heat circulation pump for exhaust gas, and a coolant heat exchanger are connected to form an auxiliary heating system. The waste heat circulation pump for exhaust gas and the coolant heat exchanger are connected by a coolant heat exchange valve II14. A connecting branch is provided on both sides of the coolant heat exchanger, and a coolant heat exchange valve I13 is provided on the branch.

[0026] Battery pack temperature sensor 4 is used to control the operation of solenoid valve I 5, solenoid valve II 16, and solenoid valve III 25 and is connected to the engine ECU. Battery performance sensor 6 is connected to BMS unit 7 and engine ECU.

[0027] The molten salt heat exchange structure also includes a molten salt storage tank 19, in which molten salt storage plates are stored. A waste heat circulation power pump is connected to the molten salt heat exchanger. The molten salt storage tank is provided with a drive structure for driving the molten salt storage plates to extend out of the molten salt storage tank and contact the exhaust pipe or to push them into the molten salt heat exchanger.

[0028] Preferably, the drive structure includes a transverse guide rail and an electric push rod structure. The electric push rod structure includes an electric telescopic rod I20 for pushing the molten salt storage plate into contact with the exhaust pipe and an electric telescopic rod II22 for pushing the molten salt storage plate along the guide rail into the molten salt heat exchanger.

[0029] The bottom of the molten salt storage tank and the side near the molten salt heat exchanger are provided with slots for the molten salt storage plate to enter and exit. The exhaust pipe of the engine is connected to the molten salt heat exchanger through a solenoid valve.

[0030] A specific example is as follows: Engine 2 drives motor 3, and uses the signal from battery temperature sensor 4 to activate solenoid valve I5 to start PTC heater 8. Engine exhaust pipe 23 is connected to molten salt storage plate 18 through electric telescopic rod I20. The signal from molten salt temperature sensor 24 enables molten salt storage plate 18 to exchange heat with molten salt heat exchanger 17. Battery temperature sensor 4 controls exhaust gas waste heat circulation power pump 15 and coolant power pump 10 to heat the battery pack. Battery temperature sensor 4 also controls solenoid valve III25 to connect engine exhaust pipe 23 to molten salt heat exchanger 17, directly using exhaust gas waste heat circulation power pump 15 to heat the battery.

[0031] The outlet of the coolant storage tank 11 is connected to the inlet of the coolant heat exchanger 12, and the outlet of the coolant heat exchanger 12 is connected to the outlet of the exhaust gas waste heat circulation power pump 15 through the coolant heat exchange valve 14.

[0032] Molten salt storage plate 18 is stored in molten salt storage tank 19. It is moved from the molten salt storage tank to the engine exhaust pipe 23 by electric telescopic rod I 20, and the molten salt storage plate 18 is heated by the engine exhaust gas. After being heated to the set temperature, the molten salt storage plate 18 is moved to the molten salt heat exchanger 17 by electric telescopic rod II 22. The molten salt heat exchanger 17 has a groove that fits the molten salt storage plate 18. The electric telescopic rod II 22 pushes the molten salt storage plate 18 into the molten salt heat exchanger 17. Solenoid valves II 16 and III 25 control the exhaust gas waste heat circulation power pump 15 to work by receiving signals from the battery temperature sensor 4.

[0033] The molten salt temperature sensor 24 transmits signals to the electric telescopic rod I 20 and the electric telescopic rod II 22. The molten salt temperature sensor 24 determines whether the electric telescopic rod I 20 and the electric telescopic rod II 22 deliver the molten salt storage plate 18 to the molten salt heat exchanger 17 or to the engine exhaust pipe 23. The battery temperature sensor 4 and the molten salt temperature sensor 24 jointly determine whether the molten salt storage plate 18 is stored in the molten salt storage box 19, which contains an insulation layer 21.

[0034] The BMS unit receives signals from the battery performance detection unit 6. If the fault threshold exceeds the set range, the BMS unit 7 sends a signal to the engine ECU, causing the engine 2 to complete the driving requirements and forcibly rest the battery pack.

[0035] In this invention, when the ambient temperature is too low, the battery pack temperature is lower than the set high-efficiency zone operating value when the car is started. The engine idle speed drives the motor to make the PTC heater on the power battery rise rapidly, and / or the engine exhaust gas is used to heat the power battery through the molten salt heat exchanger and the coolant heat exchanger to further shorten the power battery heating time. The heat is stored in the molten salt storage plate by the exhaust gas for use during the next cold start or cold charging.

[0036] This invention employs a unique protection system for hybrid vehicles, utilizing a molten salt storage plate, exhaust gas, and a PTC heater to heat the power battery. This allows the heat from the exhaust gas to be stored, maximizing energy savings, extending battery life, reducing maintenance costs, enhancing battery pack range in winter, and reducing the probability of battery pack failure during long-term operation.

[0037] The specific control strategy of the hybrid battery energy management system of this invention is as follows:

[0038] The engine control unit (ECU) receives signals from the battery pack temperature sensor, molten salt temperature sensor, and battery performance detection unit to determine the battery temperature, molten salt storage plate temperature, and battery fault threshold. The engine, controlled by the ECU, analyzes the ambient and battery pack temperatures to determine if the temperature in the molten salt storage plate is sufficient to heat the battery to its high-efficiency discharge zone. If so, it controls the waste heat circulation pump and electric telescopic rod to extend the molten salt storage plate into the molten salt heat exchanger to heat the battery. If not, it starts the engine, driving the motor to activate the PTC heater to raise the battery temperature. Simultaneously, the exhaust gas is used to heat the molten salt storage plate through the electric telescopic rod into the engine exhaust pipe. The solenoid valve between the engine exhaust pipe and the molten salt heat exchanger opens, allowing the exhaust gas to directly heat the battery. Once the molten salt storage plate reaches a certain temperature, it extends into the molten salt heat exchanger tank, where the exhaust gas waste heat circulation pump rapidly raises the battery pack temperature to its high-efficiency charge / discharge zone. The temperature sensors and temperature performance detection unit provide real-time analysis and feedback on the battery pack temperature and battery performance. If the battery pack temperature is heated to the target temperature and the battery pack reaches the high-efficiency operating range, the engine and solenoid valve will be shut off via the engine control unit.

[0039] During charging, the battery temperature sensor determines whether the battery is in the high-efficiency charging zone. If it is not in the high-efficiency zone, the heat in the molten salt storage plate is used to heat the battery by starting the waste heat circulation power pump and the motor extension rod. If the heat in the molten salt storage plate is insufficient to heat the battery to the high-efficiency charging zone, the engine is started to drive the motor and use the PTC heater. The solenoid valve between the engine exhaust pipe and the molten salt heat exchanger is opened, and the PTC heater and exhaust heat are used to reduce the preheating time of the battery charging.

[0040] The heat in the exhaust gas can be stored using molten salt storage plates and molten salt storage tanks.

[0041] During engine operation, the electric telescopic mast controls whether the molten salt storage plate is connected to the engine exhaust pipe or the molten salt heat exchanger based on the molten salt temperature sensor. When the molten salt temperature reaches the set value, the molten salt temperature sensor sends a signal to the electric telescopic mast to send the molten salt storage plate to the molten salt heat exchanger. If the temperature does not reach the set temperature, the molten salt storage plate is sent to the engine exhaust pipe to absorb heat.

[0042] After analyzing the battery pack, the battery performance detection unit sends a signal to the battery pack control unit. If the battery is above the fault threshold, the battery pack is forced into hibernation. At the same time, a feedback signal is sent to the engine control unit, allowing it to independently obtain the energy required for vehicle operation.

[0043] The control method of the hybrid battery energy management system of the present invention is as follows:

[0044] When the ambient temperature is too low, the battery pack temperature drops below the set high-efficiency operating value when the car starts. At this time, the battery temperature sensor sends a signal to the engine ECU via the BMS to start the engine. The engine drives the motor, which first moves the electric telescopic rod to extend the molten salt storage plate out of the molten salt storage tank and connect it to the engine exhaust pipe. When the molten salt temperature reaches the set temperature, the molten salt storage plate is moved by the electric telescopic rod from the engine exhaust pipe to the molten salt heat exchanger and connects with it. At this time, the exhaust pipe and the molten salt heat exchanger are controlled by a solenoid valve. The waste heat from the exhaust gas can heat the molten salt storage plate and simultaneously provide heat through a solenoid valve. The battery pack is heated by a motor that drives a PTC heater, a waste heat circulation pump, and a coolant circulation pump to heat the battery pack. Once the temperature reaches the battery pack's high-efficiency operating range, the solenoid valves of the PTC heater and the engine exhaust pipe close, ceasing to provide heat to the battery pack. At this point, the battery temperature sensor closes the PTC heater via the solenoid valve. Simultaneously, based on the set temperature of the molten salt storage plate, the molten salt storage plate is extended into the engine exhaust pipe to reach a certain temperature. Then, it is retracted into the molten salt storage tank via an electric telescopic rod for insulation, making it convenient for the next use.

[0045] When the ambient temperature is low, the charging gun can drive a waste heat circulation power pump to heat the battery using the heat stored in the molten salt storage plate during battery charging. If the temperature in the molten salt storage plate is lower than the temperature required for normal battery heating or if it is difficult to reduce the preheating time, the temperature sensor in the molten salt storage plate sends a signal to the engine control unit to start the engine. The PTC heater and exhaust gas are then used to quickly bring the battery pack to the high-efficiency charging zone, thus shortening the battery preheating time within the effective time.

[0046] When the vehicle has been driven for an extended period of time, the battery performance detection unit can identify the fault threshold set by the current battery pack. If the failure rate of the battery pack exceeds the fault threshold after a long period of operation, the battery performance detection unit sends a signal to the BMS and engine control unit to force the battery pack to rest, and the engine will then be responsible for the vehicle's driving needs.

[0047] The above description is merely an illustration of preferred embodiments of the present invention, and the above technical features can be arbitrarily combined to form multiple embodiments of the present invention.

[0048] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the concept and technical solution of the present invention, or the direct application of the concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A hybrid power battery energy management system, comprising an engine ECU, an engine, an electric motor, a BMS unit, a power battery, and a battery temperature sensor, wherein the engine ECU and the battery temperature sensor are both connected to the BMS unit, characterized in that: It also includes a PTC heater for heating the power battery, a molten salt heat exchange structure, and a coolant heat exchanger; the motor is connected to the PTC heater, the coolant heat exchanger is associated with the engine's exhaust pipe, and the molten salt heat exchange structure includes an associated molten salt storage plate and a molten salt heat exchanger, the molten salt storage plate being associated with the engine's exhaust pipe. It also includes a coolant circulation power pump, a coolant storage tank, and a waste heat circulation power pump. The coolant circulation power pump, coolant storage tank, coolant heat exchanger, and power battery form a coolant heating system. The waste heat circulation power pump is connected to the coolant heat exchanger, and a coolant heat exchange valve is provided between the waste heat circulation power pump and the coolant heat exchanger. The molten salt heat exchange structure also includes a molten salt storage tank, in which molten salt storage plates are stored. The waste heat circulation power pump is connected to the molten salt heat exchanger, and a drive structure is provided corresponding to the molten salt storage tank for driving the molten salt storage plates to extend from the molten salt storage tank to contact the exhaust pipe or to push them into the molten salt heat exchanger.

2. The hybrid battery energy management system as described in claim 1, characterized in that: A solenoid valve is provided between the motor and the PTC heater.

3. The hybrid battery energy management system as described in claim 1, characterized in that: The power battery is equipped with a battery performance testing unit, which is connected to the BMS unit.

4. The hybrid battery energy management system as described in claim 1, characterized in that: The drive structure includes a transverse guide rail and an electric push rod structure. The electric push rod structure includes an electric telescopic rod I for pushing the molten salt storage plate into contact with the exhaust pipe and an electric telescopic rod II for pushing the molten salt storage plate along the guide rail into the molten salt heat exchanger.

5. The hybrid battery energy management system as described in claim 1, characterized in that: The bottom of the molten salt storage tank and the side near the molten salt heat exchanger are provided with slots for the molten salt storage plate to enter and exit. The exhaust pipe of the engine is connected to the molten salt heat exchanger through a solenoid valve.

6. The hybrid battery energy management system as described in claim 4, characterized in that: The waste heat circulation power pump, coolant circulation power pump, and electric telescopic rod are driven by an electric motor or the vehicle's battery.

7. A control method for a hybrid power battery energy management system as described in any one of claims 1 to 6, characterized in that: The control method is as follows: when the ambient temperature is too low, the battery pack temperature is lower than the set high-efficiency zone operating value when the car is started. The engine idle speed drives the motor to make the PTC heater on the power battery rise rapidly, and / or the engine exhaust gas is used to heat the power battery through the molten salt heat exchanger and the coolant heat exchanger to further shorten the power battery heating time. The heat is stored in the molten salt storage plate by the exhaust gas for use during the next cold start or cold charging.

8. The control method as described in claim 7, characterized in that: In the control method, when the vehicle travels for too long, the battery performance detection unit can identify the fault threshold set by the current battery pack. If the failure rate of the battery pack exceeds the fault threshold after working for a long time, the battery performance detection unit sends a signal to the BMS and engine control unit to force the battery pack to rest, and the engine will complete the vehicle's driving needs.

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