Vehicle management method for low-temperature and low-electric-quantity vehicle conditions and vehicle

Abstract

The invention discloses a vehicle management method for low-temperature and low-electric-quantity vehicle conditions and a vehicle, and the method comprises the following steps: the vehicle is powered on, and the initial battery state of a power battery is obtained; the initial battery state comprises an initial battery temperature and an initial battery electric quantity; obtaining battery performance parameters of the power battery; the battery performance parameters comprise a battery temperature rise rate, a battery average discharge power and a preset temperature threshold; based on the initial battery state and the battery performance parameters, determining the estimated consumed electric quantity of the power battery allowing the recovery of the charging power; and when a driver needs to drive the vehicle, whether the vehicle is allowed to run or not is judged based on the initial battery electric quantity and the estimated consumed electric quantity. The vehicle can be prevented from lying down in the driving process, the vehicle using safety is improved, and the user experience feeling is improved.

Description

Technical Field

[0001] The present invention relates to new energy vehicles, and in particular to a vehicle management method and a vehicle for low-temperature and low-battery vehicle conditions. Background Art

[0002] The allowable charging power of the power battery is greatly affected by temperature. In a low temperature environment, the lower the power battery temperature, the smaller the allowable charging power. For lithium iron phosphate batteries, when the battery temperature drops below -25°C, the allowable charging power of the power battery is extremely small, or even 0. However, as the power battery temperature rises, the allowable charging power of the power battery gradually increases. When the allowable charging power of the power battery is 0, in order to avoid overcharging the power battery, the power battery is usually controlled to be in a micro-discharge state with a discharge power of about 1kw. Therefore, when the power battery temperature is extremely low, even after the engine is started, the power battery power will gradually decrease during the driving of the vehicle until the power battery temperature rises and the allowable charging power of the power battery is restored, and then the power battery power will stabilize and gradually increase.

[0003] When the power battery temperature is extremely low (such as -30℃, -32℃, etc.) and the power battery charge is also low (such as SOC<3%, SOC<2%, etc.), the battery charge may be reduced to 0 during vehicle driving. When the power battery charge is reduced to 0, the power battery cannot maintain the ability to discharge to the outside, which will cause the vehicle to be unable to start, causing the vehicle to break down, posing a major safety hazard to driving safety. Although the existing technology can heat the power battery by controlling the engine to increase the charging power, it takes a certain amount of time for the battery temperature to rise when the power battery is at an extremely low temperature. If the battery charge is exhausted during the rising process, the vehicle will break down during driving. Therefore, how to avoid the vehicle breaking down during use under low temperature and low power conditions is an urgent problem that the current automotive industry needs to solve. Summary of the invention

[0004] In view of this, an object of the present invention is to provide a vehicle management method and a vehicle for low-temperature and low-battery vehicle conditions, which can prevent the vehicle from breaking down during driving, thereby improving vehicle safety and enhancing user experience.

[0005] A vehicle management method for low-temperature and low-battery vehicle conditions in the present invention comprises the following steps: The vehicle is powered on, and an initial battery state of the power battery is obtained; the initial battery state includes an initial battery temperature, an initial battery power, and an initial power battery allowable charging power; Obtaining battery performance parameters of the power battery; the battery performance parameters include battery temperature rise rate, battery average discharge power, preset temperature threshold and preset power threshold; Based on the initial battery state and the battery performance parameter, it is determined whether the vehicle is allowed to travel.

[0006] Further, judging whether to allow the vehicle to travel based on the initial battery state and the battery performance parameter includes: Based on the initial battery temperature, the preset temperature threshold, the initial power battery allowable charging power and the preset power threshold, determining whether it is necessary to calculate the estimated power consumption for restoring the power battery allowable charging power; If it is determined that there is no need to calculate the estimated power consumption of the power battery to allow the charging power to be restored, the vehicle is allowed to travel; If it is determined that it is necessary to calculate the estimated power consumption of the power battery to allow charging power to be restored, then when the driver needs to drive the vehicle, the estimated power consumption is calculated, and based on the initial battery power and the estimated power consumption, it is determined whether the vehicle is allowed to drive.

[0007] Further, when the driver needs to drive the vehicle, the estimated power consumption is calculated, and based on the initial battery power and the estimated power consumption, whether to allow the vehicle to drive is determined, including: When the driver needs to drive the vehicle, determining an estimated time for the power battery to allow charging power to be restored based on the initial battery temperature, the preset temperature threshold, and the battery temperature rise rate; Determining an estimated power consumption of the power battery to allow charging power to be restored based on the estimated time and the average discharge power of the power battery; Based on the initial battery power and the estimated power consumption, it is determined whether the vehicle is allowed to travel.

[0008] Furthermore, the preset power threshold is a calibrated value. When the real-time allowable charging power of the power battery is not less than the preset power threshold, after the engine is started, the power of the power battery will no longer decrease during the driving of the vehicle; the preset temperature threshold is a calibrated value. When the real-time battery temperature of the power battery is the preset temperature threshold, the real-time allowable charging power of the power battery is the preset power threshold; the estimated power consumption for the power battery to recover the allowable charging power refers to: the power consumed when the real-time allowable charging power of the power battery increases from the initial allowable charging power to the preset power threshold.

[0009] Further, the method further includes: if it is determined that it is necessary to calculate the estimated power consumption of the power battery to allow the charging power to be restored, determining whether the driver needs to drive the vehicle; the determining whether the driver needs to drive the vehicle includes: Determine whether the driver needs to drive the vehicle; Get the vehicle's brake and gear status; If the brake is in a depressed state and the gear is switched from P gear to D gear or R gear, it is determined that the driver needs to drive the vehicle, the estimated power consumption is calculated, and based on the initial battery power and the estimated power consumption, it is determined whether the vehicle is allowed to drive; If the brake is not in the depressed state or the gear is maintained in the P gear state, it is determined that the driver does not need to drive the vehicle, and there is no need to determine whether to allow the vehicle to travel.

[0010] Further, judging whether to allow the vehicle to travel based on the initial battery power and the estimated power consumption includes: If the initial battery power is less than the estimated power consumption, determining that the vehicle is not allowed to travel; If the initial battery power is not less than the estimated power consumption, it is determined that the vehicle is allowed to travel.

[0011] Further, when it is determined that the vehicle is allowed to travel, the vehicle driving torque is not restricted; When it is determined that the vehicle is not allowed to travel, the vehicle driving torque is limited, and it is determined whether to resume vehicle travel; if the vehicle travel is resumed, the vehicle driving torque is not limited, and if the vehicle travel is not resumed, the vehicle driving torque continues to be limited.

[0012] Further, the determining whether to resume vehicle driving includes: Obtaining the real-time battery status of the power battery; the real-time battery status includes the real-time battery temperature, the real-time battery power, and the real-time allowed charging power; Get the vehicle navigation status, and when the user turns on navigation, get the estimated driving distance and estimated driving time; Acquire vehicle energy consumption information, and determine the estimated driving power consumption according to the vehicle energy consumption information, the estimated driving distance, and the estimated driving time; Based on the real-time battery temperature, the real-time battery power, the real-time allowed charging power, the estimated driving power consumption, the preset temperature threshold, the preset power threshold and the estimated power consumption, it is determined whether to resume vehicle driving.

[0013] Further, if the real-time battery temperature is not less than the preset temperature threshold, the real-time battery power is not less than the estimated power consumption, the real-time allowed charging power is not less than the preset power threshold, or the estimated driving power consumption is not greater than the estimated power consumption, it is determined that the vehicle driving is resumed; otherwise, it is determined that the vehicle driving is not resumed.

[0014] A vehicle in the present invention includes the above-mentioned vehicle management method for low-temperature and low-battery vehicle conditions.

[0015] The beneficial effects of the present invention are: (1) The present invention can, when the power battery is at low temperature and low power, determine in advance whether the vehicle has a risk of breaking down during driving before using the vehicle, and prohibit the use of the vehicle when there is a risk, thereby preventing the vehicle from breaking down due to the battery power dropping to zero during driving, thereby improving the safety of the vehicle under special conditions.

[0016] (2) The present invention can resume vehicle driving in a timely manner when the vehicle condition permits, avoiding long-term prohibition of vehicle use and improving user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to make the purpose, technical solution and beneficial effects of the present invention clearer, the present invention provides the following drawings for illustration: Figure 1 It is a schematic diagram of the process of the present invention; Figure 2 For Figure 1 Schematic diagram of the process of refinement steps; Figure 3 For Figure 2 Schematic diagram of the process for further refinement of the steps; Figure 4 For Figure 2 or Figure 3 Schematic diagram of the process flow of the refinement step in S5. DETAILED DESCRIPTION

[0018] The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings and embodiments.

[0019] like Figure 1-Figure 4 As shown, a vehicle management method for low-temperature and low-battery vehicle conditions in this embodiment includes the following steps: S1. The vehicle is powered on, and the initial battery state of the power battery is obtained; the initial battery state includes the initial battery temperature, the initial battery power, and the initial allowable charging power. The initial battery temperature may be the lowest temperature of each battery cell of the power battery.

[0020] When the vehicle is powered on, when the initial battery temperature is low, that is, when the initial battery temperature is lower than the preset heating threshold, the vehicle will start to heat the power battery through the thermal management system. Heating the power battery belongs to the existing technology in this technical field, and its specific principle will not be repeated here.

[0021] S2. Obtain battery performance parameters of the power battery; the battery performance parameters include battery temperature rise rate, battery average discharge power, preset temperature threshold and preset power threshold.

[0022] The preset power threshold is a calibration value. When the real-time allowable charging power of the power battery is not less than the preset power threshold, after the engine is started, the engine output power can be used to charge the battery after the generator generates electricity, and the power of the power battery will no longer decrease during the vehicle's driving. The preset temperature threshold is a calibration value. When the real-time battery temperature of the power battery is the preset temperature threshold, the real-time allowable charging power of the power battery is the preset power threshold. The calibration value of the preset power threshold is obtained through actual vehicle testing, generally 3kw-5kw.

[0023] The battery temperature rise rate is also a calibrated value, which is obtained by performing actual vehicle tests at different ambient temperatures and battery temperatures. For example, when the ambient temperature is -30°C and the initial battery temperature is -30°C, the vehicle is driven and the battery temperature rise rate measured at the ambient temperature and the initial battery temperature is obtained through the battery temperature rise value and the rise time. Then, the test data of the battery temperature rise rate is obtained under different ambient temperatures and initial battery temperatures. These test data are stored in the controller in the form of a table through calibration settings. By comparing the initial battery temperature of the power battery with the ambient temperature and the test data, the battery temperature rise rate of the power battery at this time can be obtained by looking up the table.

[0024] S3. Based on the initial battery state and the battery performance parameters, determine whether the vehicle is allowed to travel.

[0025] This step specifically includes: S301, based on the initial battery temperature, the preset temperature threshold, the initial power battery allowed charging power and the preset power threshold, determine whether it is necessary to calculate the estimated power consumption of the power battery allowed charging power recovery; the estimated power consumption of the power battery allowed charging power recovery refers to: the power consumed when the real-time allowed charging power of the power battery rises from the initial allowed charging power to the preset power threshold. Step S301 specifically includes: S3011. If the initial battery temperature is not less than the preset temperature threshold, or the initial power battery allowable charging power is not less than the preset power threshold, it is determined that there is no need to calculate the estimated power consumption for the power battery to recover the allowable charging power, and the vehicle is allowed to travel, that is, directly enter step S6.

[0026] S3012: If the initial battery temperature is lower than the preset temperature threshold, or / and the initial power battery allowable charging power is lower than the preset power threshold, it is determined that the estimated power consumption required to restore the power battery allowable charging power needs to be calculated, and then the process proceeds to step S302.

[0027] S302: Determine whether the vehicle is allowed to drive, wherein determining whether the driver needs to drive the vehicle includes: S3021, obtaining the brake and gear status of the vehicle; S3022, if the brake is in a depressed state and the gear is switched from P gear to D gear or R gear, it is determined that the driver needs to drive the vehicle, the estimated power consumption is calculated, and based on the initial battery power and the estimated power consumption, it is determined whether the vehicle is allowed to drive, that is, entering step S303; S3023. If the brake is not in the depressed state or the gear is maintained in the P gear state, it is determined that the driver does not need to drive the vehicle, and there is no need to determine whether the vehicle is allowed to drive, and the process returns to step S3021.

[0028] S303, calculating the estimated power consumption, and judging whether to allow the vehicle to travel based on the initial battery power and the estimated power consumption. This step specifically includes: S3031. When the driver needs to drive the vehicle, determining an estimated time for the power battery to allow charging power to be restored based on the initial battery temperature, the preset temperature threshold, and the battery temperature rise rate; Specifically, the calculation formula for the estimated time that the power battery allows the charging power to be restored is t=(Ttar-Tmin) / a; where t is the estimated time that the power battery allows the charging power to be restored, Ttar is the preset temperature threshold, Tmin is the initial battery temperature, and a is the battery temperature rise rate.

[0029] S3032: Determine an estimated power consumption of the power battery to allow charging power to be restored based on the estimated time and the average discharge power of the power battery.

[0030] Specifically, the calculation formula for the estimated power consumption of the power battery allowing the charging power to be restored is Etar=P*t; wherein Etar is the estimated power consumption of the power battery allowing the charging power to be restored, P is the average discharge power of the power battery, and t is the estimated time for the power battery to allow the charging power to be restored.

[0031] The average discharge power of the power battery is obtained by testing the actual vehicle under different ambient temperatures, different power battery temperatures and remaining power. For example: when the power temperature is -30℃ and the battery power is 5%, the vehicle is driven after the engine is started, and the power consumed and the time when the power battery power drops to the minimum value are recorded to obtain the average discharge power of the power battery. Then, under different ambient temperatures, different power battery temperatures and remaining power conditions, the test data of the average discharge power of the power battery are obtained. These test data are stored in the controller in the form of a table through calibration settings. By comparing the ambient temperature of the vehicle at this time, the power battery temperature of the vehicle at this time and the remaining power with the test data, the average discharge power of the power battery at this time can be obtained by looking up the table.

[0032] The allowable charging power of the power battery is greatly affected by temperature. In a low temperature environment, the lower the temperature of the power battery, the smaller the allowable charging power. As the temperature of the power battery rises, the allowable charging power of the power battery gradually increases. When the allowable charging power of the power battery is 0, in order to avoid overcharging of the power battery, the power battery is usually controlled to be in a micro-discharge state, and the discharge power is about 1kw. Therefore, when the temperature of the power battery is extremely low, even after the engine is started, the power battery power will gradually decrease during the driving process of the vehicle until the power battery temperature rises and the allowable charging power of the power battery is restored, and then the power battery power will stabilize and gradually increase. When the power battery is at an extremely low temperature, it takes a certain amount of time for the battery temperature to rise. If the battery power is exhausted during the rising process, it will cause the vehicle to break down during driving. In this step, the estimated time for the power battery to allow the charging power to recover and the estimated power consumption for the power battery to allow the charging power to recover are calculated, which can be helpful for the subsequent judgment of whether the vehicle is allowed to drive.

[0033] S3033. Determine whether to allow the vehicle to travel based on the initial battery power and the estimated power consumption.

[0034] Specifically, if the initial battery power is less than the estimated power consumption, it is determined that the vehicle is not allowed to travel, and the process goes to step S4; if the initial battery power is not less than the estimated power consumption, it is determined that the vehicle is allowed to travel, and the process goes to step S6.

[0035] S4, when it is determined that the vehicle is not allowed to drive, the vehicle driving torque is limited, and at this time, the vehicle computer can also prompt the user that the vehicle cannot be driven, and prompt the user that the battery temperature is low, the vehicle is prohibited from driving, and the waiting time, etc. Then, enter step S5.

[0036] S5. Determine whether to resume vehicle driving; if the vehicle driving is resumed, the vehicle driving torque is not limited; if the vehicle driving is not resumed, the vehicle driving torque continues to be limited.

[0037] This step specifically includes: S501. Acquire the real-time battery status of the power battery; the real-time battery status includes the real-time battery temperature, the real-time battery power, and the real-time allowed charging power.

[0038] S502: Obtain vehicle navigation status, and when the user turns on navigation, obtain an estimated driving distance and an estimated driving time.

[0039] S503, obtaining vehicle energy consumption information, and determining the estimated driving power consumption according to the vehicle energy consumption information, the estimated driving distance, and the estimated driving time. The vehicle energy consumption information may be the official energy consumption information of the vehicle model stored in the vehicle machine or the cloud; the vehicle energy consumption information may be the personalized vehicle energy consumption information stored in the vehicle machine or the cloud based on the user's habits, for example, the personalized vehicle energy consumption information may be the power consumption per kilometer or per unit driving time obtained based on the user's historical total driving distance, historical total driving time, and historical total power consumption; the vehicle energy consumption information may also be the power consumption per kilometer or per unit driving time of all users of the vehicle model connected to the cloud.

[0040] S504: Determine whether to resume vehicle driving based on the real-time battery temperature, the real-time battery power, the real-time allowed charging power, the estimated driving power consumption, the preset temperature threshold, the preset power threshold, and the estimated power consumption: If the real-time battery temperature is not less than the preset temperature threshold, the real-time battery power is not less than the estimated power consumption, the real-time allowed charging power is not less than the preset power threshold, or the estimated driving power consumption is not greater than the estimated power consumption, it is determined that the vehicle driving is resumed; then, the prompt to the user that the vehicle cannot be driven is cancelled, and the prompt is entered into step S6, such as the low battery temperature, the prohibition of vehicle driving, and the waiting time.

[0041] Otherwise, it is determined that the vehicle driving is not resumed.

[0042] That is, if the real-time battery temperature is lower than the preset temperature threshold, the real-time battery power is lower than the estimated power consumption, the real-time allowed charging power is lower than the preset power threshold, and the estimated driving power consumption is higher than the estimated power consumption, it is determined not to resume vehicle driving.

[0043] S6. When it is determined that the vehicle is allowed to travel, the vehicle driving torque is not restricted.

[0044] From the above, it can be seen that the vehicle management method for low-temperature and low-battery conditions in this embodiment can, under conditions of low-temperature and low-battery power batteries, determine in advance whether the vehicle has a risk of breaking down during driving before using the vehicle, and prohibit the use of the vehicle when there is a risk, thereby preventing the vehicle from breaking down due to the battery power dropping to 0 during driving, thereby improving the safety of the vehicle under special conditions.

[0045] Furthermore, the vehicle management method for low-temperature and low-battery vehicle conditions in this embodiment can resume vehicle driving in a timely manner when vehicle conditions permit, avoiding long-term prohibition of vehicle use and improving user experience.

[0046] A vehicle in this embodiment includes the above-mentioned vehicle management method for low-temperature and low-battery vehicle conditions.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A vehicle management method for low temperature and low battery conditions, characterized in that: The following steps are involved: The vehicle is powered on and the initial battery status of the power battery is obtained; The initial battery state includes the initial battery temperature, the initial battery power and the initial power battery allowable charging power; Obtaining battery performance parameters of the power battery; the battery performance parameters include battery temperature rise rate, battery average discharge power, preset temperature threshold and preset power threshold; Based on the initial battery state and the battery performance parameter, it is determined whether the vehicle is allowed to travel.

2. The vehicle management method for low temperature and low battery condition according to claim 1, characterized in that: The determining whether to allow the vehicle to travel based on the initial battery state and the battery performance parameter includes: Based on the initial battery temperature, the preset temperature threshold, the initial power battery allowable charging power and the preset power threshold, determining whether it is necessary to calculate the estimated power consumption for restoring the power battery allowable charging power; If it is determined that there is no need to calculate the estimated power consumption of the power battery to allow the charging power to be restored, the vehicle is allowed to travel; If it is determined that it is necessary to calculate the estimated power consumption of the power battery to allow charging power to be restored, then when the driver needs to drive the vehicle, the estimated power consumption is calculated, and based on the initial battery power and the estimated power consumption, it is determined whether the vehicle is allowed to drive.

3. The vehicle management method for low temperature and low battery condition according to claim 2, characterized in that: When the driver needs to drive the vehicle, calculating the estimated power consumption, and judging whether to allow the vehicle to travel based on the initial battery power and the estimated power consumption, includes: When the driver needs to drive the vehicle, determining an estimated time for the power battery to allow charging power to be restored based on the initial battery temperature, the preset temperature threshold, and the battery temperature rise rate; Determining an estimated power consumption of the power battery to allow charging power to be restored based on the estimated time and the average discharge power of the power battery; Based on the initial battery power and the estimated power consumption, it is determined whether the vehicle is allowed to travel.

4. The vehicle management method for low temperature and low battery condition according to claim 3, characterized in that: The preset power threshold is a calibration value. When the real-time allowable charging power of the power battery is not less than the preset power threshold, after the engine is started, the power battery power will no longer decrease during the vehicle driving process; The preset temperature threshold is a calibrated value. When the real-time battery temperature of the power battery is the preset temperature threshold, the real-time allowable charging power of the power battery is the preset power threshold; the estimated power consumption for recovery of the allowable charging power of the power battery refers to: the power consumed when the real-time allowable charging power of the power battery increases from the initial allowable charging power to the preset power threshold.

5. The vehicle management method for low temperature and low battery condition according to claim 2, characterized in that: The method further includes: if it is determined that the estimated power consumption of the power battery that allows the charging power to be restored needs to be calculated, determining whether the driver needs to drive the vehicle; the determining whether the driver needs to drive the vehicle includes: Get the vehicle's brake and gear status; If the brake is in a depressed state and the gear is switched from P gear to D gear or R gear, it is determined that the driver needs to drive the vehicle, the estimated power consumption is calculated, and based on the initial battery power and the estimated power consumption, it is determined whether the vehicle is allowed to drive; If the brake is not in the depressed state or the gear is maintained in the P gear state, it is determined that the driver does not need to drive the vehicle, and there is no need to determine whether to allow the vehicle to travel.

6. The vehicle management method for low temperature and low battery condition according to claim 3, characterized in that: The determining whether to allow the vehicle to travel based on the initial battery power and the estimated power consumption includes: If the initial battery power is less than the estimated power consumption, determining that the vehicle is not allowed to travel; If the initial battery power is not less than the estimated power consumption, it is determined that the vehicle is allowed to travel.

7. The vehicle management method for low temperature and low battery condition according to claim 3, characterized in that: When it is determined that the vehicle is allowed to move, the vehicle driving torque is not limited; When it is determined that the vehicle is not allowed to travel, limiting the vehicle driving torque, and determining whether to resume the vehicle travel; If the vehicle is resumed, the vehicle driving torque is not limited. If the vehicle is not resumed, the vehicle driving torque continues to be limited.

8. The vehicle management method for low temperature and low battery condition according to claim 7, characterized in that: The determining whether to resume vehicle driving comprises: Obtaining the real-time battery status of the power battery; the real-time battery status includes the real-time battery temperature, the real-time battery power, and the real-time allowed charging power; Get the vehicle navigation status, and when the user turns on navigation, get the estimated driving distance and estimated driving time; Acquire vehicle energy consumption information, and determine the estimated driving power consumption according to the vehicle energy consumption information, the estimated driving distance, and the estimated driving time; Based on the real-time battery temperature, the real-time battery power, the real-time allowed charging power, the estimated driving power consumption, the preset temperature threshold, the preset power threshold and the estimated power consumption, it is determined whether to resume vehicle driving.

9. The vehicle management method for low temperature and low battery condition according to claim 8, characterized in that: If the real-time battery temperature is not less than the preset temperature threshold, the real-time battery power is not less than the estimated power consumption, the real-time allowed charging power is not less than the preset power threshold, or the estimated driving power consumption is not greater than the estimated power consumption, it is determined that the vehicle driving is resumed; Otherwise, it is determined that the vehicle driving is not resumed.

10. A vehicle, characterized in that: It includes a vehicle management method for low temperature and low battery conditions as described in any one of claims 1-9.

Images