A low-temperature low-SOC mode hybrid commercial vehicle thermal management architecture and control method

Abstract

The present application relates to new energy vehicle thermal management control technical field, specifically, the present application relates to a kind of low-temperature low SOC mode under hybrid commercial vehicle's thermal management architecture and control method, including range extender engine, CO clutch, generator and 12V starter normally closed water valve, Chiller heat exchanger, electronic water pump, power battery etc., under low-temperature low SOC environment, range extender engine water circulation pipeline and battery water circulation pipeline are connected by Chiller heat exchanger, range extender engine water circulation pipeline is provided with engine water temperature sensor, mechanical water pump, normally closed water valve.Battery water circulation pipeline is provided with electronic water pump, battery inlet water temperature sensor.Power battery is equipped with heating film.Solved in low-temperature low SOC environment, power battery self heating film stops working, vehicle cannot be charged, cannot drive, can only wait for rescue problem.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new energy vehicle thermal management control, in particular, the present application relates to a low-temperature low-SOC mode hybrid commercial vehicle thermal management architecture and control method. BACKGROUND

[0002] Pure electric new energy logistics light truck has spread all over the country, and people's attention and acceptance of new energy light truck are increasing, and range-extended new energy light truck is also highly regarded because it has all the advantages of pure electric vehicles. In terms of endurance, range-extended light trucks do not have the "mileage anxiety" of pure electric light trucks. The endurance mileage of pure electric light trucks depends on the battery capacity and working conditions. Once the power is insufficient, it needs to be charged for a long time. Range-extended light trucks can generate electricity through the fuel engine to supplement the power, increase the endurance, and supplement the energy. Pure electric light trucks take a long time to charge, especially at fast charging piles, which may take tens of minutes to several hours to fully charge. Range-extended light trucks are more flexible in supplementing energy. When the power is insufficient, it can be refueled at the gas station within a few minutes to continue generating electricity, saving time and improving transportation efficiency.

[0003] Although the range-extended new energy light truck has the above advantages over the pure electric vehicle, it also has the disadvantages of the pure electric vehicle. First, in the extremely cold environment scenario, the power battery SOC is lower than a certain threshold, the vehicle power is limited, and the heating film of the battery stops working. At this time, the vehicle is completely unable to run and causes the vehicle to be stranded, and it can only wait for rescue. Secondly, the vehicle is immersed for a night, and the power battery is frozen. At this time, the power battery has a weak discharge capacity due to its own characteristics, and the charging capacity also decreases sharply. Although the range-extended new energy light truck has a range extender, it does not directly participate in driving. Therefore, in this scenario, the range extender may fail to start, even if it starts successfully, the battery has a limit to prevent overcharging, which causes the range extender to be unable to provide the required high-power electric energy for the vehicle. At the same time, if the power battery is overcharged, it will cause serious damage to the battery. SUMMARY

[0004] The present application provides a low-temperature low-SOC mode hybrid commercial vehicle thermal management architecture and control method. VCU controls the closing or opening of the CO clutch by judging the discharge capacity of the power battery at this time, and the engine starts in different ways (generator counter-drag or 12V starter counter-drag). The heat generated by the engine after starting is transmitted to the power battery through the heat exchanger for heating. When the battery is heated to a certain temperature, the battery overcharge prevention limit is removed, and the range extender can follow the demand power of the vehicle. At this time, the vehicle can escape from the trouble without rescue and run normally.

[0005] In order to achieve the above object, the technical scheme adopted by the present application is: a low-temperature low-SOC mode thermal management architecture of a hybrid commercial vehicle, comprising an extended-range engine, a CO clutch, a generator, a 12V starter and a power battery, etc., under low-temperature low-SOC environment, the VCU controls the closing or opening of the CO clutch by judging the discharge capacity of the power battery at this time, the extended-range engine is started in the mode of generator reverse traction or 12V starter reverse traction, a water circulation pipeline is arranged between the extended-range engine and the battery, the water circulation pipeline of the extended-range engine and the water circulation pipeline of the battery are connected through a Chiller heat exchanger, the water circulation pipeline of the extended-range engine is provided with an engine water temperature sensor, a mechanical water pump and a normally closed water valve, the water circulation pipeline of the battery is provided with an electronic water pump and a battery water inlet temperature sensor, and the power battery is provided with a heating film

[0006] Further limited, a control method of a low-temperature low-SOC mode thermal management architecture of a hybrid commercial vehicle,

[0007] The specific steps are as follows: step S1, in an extremely cold environment, the vehicle SOC is lower than a threshold S%, and the vehicle is parked for a night, the next day the vehicle is normally powered on, and the whole vehicle enters a high-voltage READY state;

[0008] Step S2, the VCU of the whole vehicle detects whether the battery SOC and the minimum temperature of the battery cell are lower than T1, T1 is a temperature threshold value allowed by the power battery for the extended-range engine power to follow, if not, the whole vehicle can normally run, if yes, step S3 is executed;

[0009] Step S3, the instrument ICM displays "vehicle warming up, please do not drive", and the VCU detects whether the discharge capacity of the power battery is not lower than a threshold P1, P1 is the first threshold value for the CO clutch to close, if yes, step S4 is executed;

[0010] Step S4, the VCU controls the CO clutch to close, the EMS and the GCU receive the start instruction of the VCU, and the GCU controls the generator to reverse traction start;

[0011] Step S5, after the engine is successfully started, it runs in an idle state, the CO clutch remains in the state at the time of starting, and at the same time, the VCU detects whether the charging capacity of the power battery is not lower than a threshold P2, P2 is the second threshold value for the CO clutch to close, if yes, step S6 is executed;

[0012] Step S6, the VCU controls the CO clutch to close, and the GCU requests the engine speed to be R1;

[0013] Step S7, the VCU detects whether the engine water temperature is not lower than an engine coolant temperature threshold T3 and the minimum temperature of the battery cell is not higher than T2, T2 is a temperature threshold value for the power battery to stop heating, if not, the engine speed is kept as R1.

[0014] Step S8, the VCU controls the normally closed water valve to open, at the same time, the battery water pump is correspondingly operated, the VCU detects whether the battery pack inlet water temperature is not less than T4, T4 is a temperature threshold value at which the normally closed water valve is closed, if not, the battery water pump is kept to be correspondingly operated, if yes, the VCU controls the normally closed water valve to be closed, and the water pump is kept to be correspondingly operated;

[0015] Step S9, the VCU further detects whether the battery pack inlet water temperature is less than or equal to T4-△T5, wherein △T5 represents a hysteresis interval of the battery pack inlet water temperature, a temperature threshold value at which the normally closed water valve is controlled to be opened, if not, the VCU controls the normally closed water valve to be closed, and the water pump is correspondingly operated, if yes, the VCU controls the normally closed water valve to be opened, at the same time, the battery water pump is correspondingly operated;

[0016] Step S10, the VCU detects whether the lowest temperature of the power battery cell is greater than T1, if not, the previous state is kept, if yes, step S11 is executed;

[0017] Step S11, the VCU switches to the driving mode, the instrument display ICM displays that the vehicle is ready to drive, the vehicle is normally driven, the range-extending power follows the demand of the whole vehicle, and the driving is met.

[0018] Further limitation, further comprising step S12, after the vehicle is normally driven, the VCU detects whether the lowest temperature of the battery cell is greater than T2, if yes, the VCU controls the normally closed water valve to be closed, and the battery water pump is closed, if not, the VCU controls the normally closed water valve to be opened, at the same time, the battery water pump is correspondingly operated.

[0019] Further limitation, step S4 further comprises step S4.1, in step S3, the VCU detects whether the power battery discharge capacity is not less than a threshold value P1, if not, step S4.1 is executed, in step S4.1, the VCU controls the CO clutch to be opened, the EMS receives the VCU starting instruction, the VCU closes the 12V starter relay, and the 12V starter is started in reverse drag.

[0020] Further limitation, further comprising step S5.1, in step S5, the VCU detects whether the power battery charging capacity is not less than a threshold value P2, if not, step S5.1 is executed, in step S5.1, the VCU controls the CO clutch to be opened, the GCU requests the engine speed to be R2, at the same time, the VCU detects whether the power battery charging capacity is greater than or equal to P2, if not, the current state is kept, if yes, step S6 is executed.

[0021] The beneficial effects of the above technical solutions are:

[0022] The beneficial effects of the above technical solutions are:

[0023] VCU judges the discharge capacity of the power battery at this time, controls the closing or opening of the CO clutch, and the engine starts in different ways (generator reverse drag or 12V starter reverse drag). The heat generated after the engine starts is transmitted to the power battery through the heat exchanger for heating, and when the battery is heated to a certain temperature, the battery overcharge prevention limit is removed, the range extender can follow the demand power of the vehicle, and at the same time, the battery can be charged. At this time, the vehicle can get out of trouble without rescue and run normally. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 A thermal management architecture for a commercial vehicle in a low-temperature low-SOC mode

[0025] Figure 2 A general control flowchart of the present application

[0026] The figures are identified as follows: 1 - range extended engine, 2 - CO clutch, 3 - generator, 4 - 12V starter, 5 - power battery, 6 - Chiller heat exchanger, 7 - engine water temperature sensor, 8 - heating film, 9 - mechanical water pump, 10 - battery water pump, 11 - battery water inlet temperature sensor, 12 - normally closed water valve. DETAILED DESCRIPTION

[0027] The specific embodiments of the present application will be further described below with reference to the accompanying drawings, and the purpose is to help those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solution of the present application, and to help its implementation.

[0028] The present application is a kind of low-temperature low-SOC mode thermal management architecture and control method of hybrid commercial vehicle, solve the problem that in low-temperature low-SOC environment, power battery self heating film stops working, vehicle cannot be charged, cannot drive, can only wait for rescue, secondly, the vehicle is static for a night, the power battery is frozen, at this time, the power battery is due to its own characteristics, the discharge capacity decreases, the charging capacity also decreases sharply, the range extended new energy light truck has a range extender, but it does not directly participate in driving, so in this scenario, the range extender may not start successfully, even if it starts successfully, due to weak battery charging capacity, the battery has an overcharge prevention limit, which prevents the range extender from providing the required high-power electric energy for the vehicle. At the same time, if the power battery is overcharged, it will cause serious damage to the battery.

[0029] As Figure 1 and Figure 2As shown, a low-temperature low-SOC mode hybrid commercial vehicle thermal management architecture includes a range extender engine 1, a CO clutch 2, a generator 3 and a 12V starter 4. The VCU controls the closing or opening of the CO clutch 2 by judging the discharge capacity of the power battery at this time. The range extender engine 1 is started in the mode of generator 3 reverse drag or 12V starter 4 reverse drag. The range extender engine 1 water circulation pipeline and the battery 5 water circulation pipeline are connected through a Chiller heat exchanger 6. The range extender engine water circulation pipeline is provided with a water temperature sensor 7, a mechanical water pump 9 and a normally closed water valve 12. The battery 5 water circulation pipeline is provided with an electronic water pump 10 and a battery water inlet water temperature sensor 11. The power battery is provided with a heating film 8.

[0030] A control method of a low-temperature low-SOC mode hybrid commercial vehicle thermal management architecture, the specific steps are as follows:

[0031] Step S1, in extremely cold environment, the vehicle SOC is lower than the threshold S%, and the vehicle is parked for a night. The next day, the vehicle is normally

[0032] The high-voltage is turned on, and the whole vehicle enters the high-voltage READY state;

[0033] Step S2, the VCU detects whether the battery SOC and the lowest temperature of the cell are lower than T1. T1 is the temperature threshold value of the power battery allowing the range extender power to follow. If not, the vehicle can be normally operated. If yes, step S3 is executed.

[0034] Step S3, the instrument ICM displays "vehicle warming, please do not drive", and the VCU detects whether the discharge capacity of the power battery is not lower than the threshold P1. P1 is the first threshold value of the CO clutch closing. If yes, step S4 is executed. If not, step S4.1 is executed.

[0035] Step S4, the VCU controls the CO clutch to close, the EMS and the GCU receive the VCU starting instruction, and the GCU controls the generator to reverse drag and start.

[0036] Step S4.1, the VCU controls the CO clutch to open, the EMS receives the VCU starting instruction, and the VCU closes the 12V

[0037] starter relay, and the 12V starter is started in reverse drag mode;

[0038] Step S5, after the engine is successfully started, it is operated in the idle state. The CO clutch remains in the state at the time of starting. At the same time, the VCU detects whether the charging capacity of the power battery is not lower than the threshold P2. P2 is the second threshold value of the CO clutch closing. If yes, step S6 is executed. If not, step S5.1 is executed.

[0039] Step S5.1, VCU controls CO clutch to open, GCU requests engine speed to be R2, while VCU detects whether the charging capability of power battery is greater than or equal to P2, if not, the current state is maintained, if yes, step S6 is executed;

[0040] Step S6, VCU controls CO clutch to close, GCU requests engine speed to be R1;

[0041] Step S7, VCU detects whether the engine water temperature is not lower than engine coolant temperature threshold T3 and the minimum temperature of the battery cell is not higher than T2, T2 is the temperature threshold at which the power battery stops heating, if not, the engine speed is maintained to be R1;

[0042] Step S8, VCU controls the normally closed water valve to open, at the same time, the battery water pump is operated accordingly, VCU detects whether the battery pack water temperature is not less than T4, T4 is the temperature threshold at which the normally closed water valve is closed, if not, the battery water pump is maintained to be operated accordingly, if yes, VCU controls the normally closed water valve to be closed, and the water pump is maintained to be operated accordingly;

[0043] Step S9, VCU further detects whether the battery pack water temperature is less than or equal to T4-△T5, wherein △T5 represents the temperature threshold at which the normally closed water valve is controlled to be opened, if not, the state that VCU controls the normally closed water valve to be closed and the water pump is operated accordingly is maintained, if yes, VCU controls the normally closed water valve to be opened, at the same time, the battery water pump is operated accordingly;

[0044] Step S10, VCU detects whether the minimum temperature of the battery cell is greater than T1, if not, the previous state is maintained, if yes, step S11 is executed;

[0045] Step S11, VCU switches to driving mode, the instrument display ICM displays “warm-up is completed, and the vehicle can be driven”, the vehicle is normally driven, the extended range power follows the demand of the whole vehicle, and the driving is met;

[0046] Step S12, after the vehicle is normally driven, VCU detects whether the minimum temperature of the battery cell is greater than T2, if yes, VCU controls the normally closed water valve to be closed, and the battery water pump is closed, if not, VCU controls the normally closed water valve to be opened, at the same time, the battery water pump is operated accordingly.

[0047] The above describes the present application by way of example with reference to the drawings. Obviously, the specific implementation of the present application is not limited to the above-described manner, and various non-essential improvements are made by using the method concept and technical solution of the present application; or the above-mentioned concept and technical solution of the present application is directly applied to other occasions without improvement, which is within the protection scope of the present application.

Claims

1. A control method for a thermal management architecture of a low-temperature low-SOC mode hybrid commercial vehicle, the control method being applied to a low-temperature low-SOC mode hybrid commercial vehicle thermal management architecture, comprising a range-extender engine, a CO clutch, a generator and a 12V starter and a power battery, in a low-temperature low-SOC environment, the VCU controls the closing or opening of the CO clutch by judging the discharge capacity of the power battery at this time, the range-extender engine is started in the form of generator reverse traction or 12V starter reverse traction, a water circulation pipeline is arranged between the range-extender engine and the battery, the range-extender engine water circulation pipeline and the battery water circulation pipeline are connected through a Chiller heat exchanger, the range-extender engine water circulation pipeline is provided with an engine water temperature sensor, a mechanical water pump and a normally closed water valve, the battery water circulation pipeline is provided with an electronic water pump and a battery water inlet water temperature sensor, the power battery is provided with a heating film, characterized in that: The specific steps are as follows: Step S1, in an extremely cold environment, the vehicle SOC is lower than the threshold S%, and the vehicle is parked for a night, the next day the vehicle is normally powered on high voltage, and the whole vehicle enters the high voltage READY state; Step S2, the VCU of the whole vehicle detects whether the battery SOC and the minimum temperature of the battery cell are lower than T1, T1 is a temperature threshold value allowed by the power battery for the power follower of the range extender, if not, the whole vehicle can be normally operated, if yes, step S3 is executed; Step S3, the instrument ICM displays "vehicle warming up, please do not drive", and the VCU detects whether the discharging capacity of the power battery is not lower than a threshold P1, P1 is a first threshold value for closing the CO clutch, if yes, step S4 is executed; Step S4, the VCU controls the CO clutch to be closed, the EMS and the GCU receive the starting instruction of the VCU, and the GCU controls the generator to be started in reverse traction; Step S5, after the engine is successfully started, the engine is operated in an idle state, the CO clutch is kept in the state at the time of starting, and the VCU detects whether the charging capacity of the power battery is not lower than a threshold P2, P2 is a second threshold value for closing the CO clutch, if yes, step S6 is executed; Step S6, the VCU controls the CO clutch to be closed, and the GCU requests the engine speed to be R1; Step S7, the VCU detects whether the engine water temperature is not lower than an engine coolant temperature threshold T3 and the minimum temperature of the battery cell is not higher than T2, T2 is a temperature threshold value at which the power battery stops heating, if not, the engine speed is kept as R1; Step S8, the VCU controls the normally closed water valve to be opened, and the battery water pump is correspondingly operated, the VCU detects whether the battery pack water inlet temperature is not less than T4, T4 is a temperature threshold value at which the normally closed water valve is closed, if not, the battery water pump is correspondingly operated, if yes, the VCU controls the normally closed water valve to be closed, and the water pump is kept in corresponding operation; Step S9, the VCU further detects whether the battery pack water inlet temperature is less than or equal to T4-△T5, wherein △T5 represents a hysteresis interval of the battery pack water inlet temperature, a temperature threshold value for controlling the normally closed water valve to be opened, if not, the VCU controls the normally closed water valve to be kept closed, and the water pump is correspondingly operated, if yes, the VCU controls the normally closed water valve to be opened, and the battery water pump is correspondingly operated; Step S10, the VCU detects whether the minimum temperature of the power battery cell is greater than T1, if not, the previous state is kept, if yes, step S11 is executed; Step S11, the VCU is switched to a driving mode, the instrument ICM displays "warming up is completed, and driving is available", the vehicle is normally driven, the power of the range extender follows the demand of the whole vehicle, and driving is met.

2. The control method of the thermal management architecture of a hybrid commercial vehicle in a low-temperature low-SOC mode according to claim 1, characterized in that: Further comprising step S12, Step S12, after the vehicle is normally driven, the VCU detects whether the minimum temperature of the battery cell is greater than T2, if yes, the VCU controls the normally closed water valve to be closed, and the battery water pump is closed, if not, the VCU controls the normally closed water valve to be opened, and the battery water pump is correspondingly operated.

3. The control method of the thermal management architecture of a hybrid commercial vehicle in a low-temperature low-SOC mode according to claim 1, characterized in that: Step S4 further comprises step S4.1, in step S3, the VCU detects whether the discharging capacity of the power battery is not lower than the threshold P1, if not, step S4.1 is executed, Step S4.1, VCU controls CO clutch to open, EMS receives VCU start instruction, VCU closes 12V starter relay, 12V starter performs reverse-dragging start.

4. The control method of the thermal management architecture of a hybrid commercial vehicle in a low-temperature low-SOC mode according to claim 1, characterized in that: Also included is step S5.1, in step S5, VCU detects whether the power battery charging capability is not lower than threshold P2, if not, step S5.1 is performed; Step S5.1, VCU controls CO clutch to open, GCU requests engine speed to be R2, and at the same time, VCU detects whether the power battery charging capability is ≥P2, if not, the current state is maintained, if yes, step S6 is performed.

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