Method and apparatus for determining power requirements based on vehicle limp-home failure

Abstract

The application provides a power supply demand determination method and device based on vehicle failure limp, and relates to the technical field of power supply of vehicle auxiliary equipment. The method comprises the following steps: acquiring the working current of each load of a basic power chassis low-voltage load type; acquiring the working current of each load of a basic regulation requirement load type; acquiring the basic current of each load of a comfort function load type; calculating the sum of the basic current of each load of the basic power chassis low-voltage load type, the basic regulation requirement load type and the comfort function load type as a total load current; determining a limp start electric quantity according to the residual electric quantity of a vehicle storage battery in a driving process; acquiring a limp stop electric quantity according to the attribute of the vehicle storage battery; and determining a low-voltage power supply capacity requirement value based on vehicle failure limp according to the limp time, the total load current, the limp start electric quantity and the limp stop electric quantity. The application can fully meet the energy consumption requirement under the limp condition.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power supply for vehicle auxiliary equipment, and more particularly to a power demand determination method and device based on vehicle limp-home. BACKGROUND

[0002] Limp-home refers to a state in which a vehicle enters a protection mode to limit power output and speed after detecting certain faults, so as to ensure safe driving and prevent further damage.

[0003] Currently, if the DC / DC converter fails to work, the low-voltage power supply system is in a degraded mode. The driver can control the power system simply, so that the car can be driven back home or to a nearby garage for repair. This process requires the battery not to be discharged, which can ensure the safe arrival of the vehicle and does not affect the normal use of the battery next time. The scene of the vehicle limp-home is demanding for the battery, so it is necessary to calculate the battery capacity demand based on this scene to meet the power demand of the vehicle limp-home scene.

[0004] Patent document CN116749978A discloses a control method for vehicle limp-home driving, obtaining driving state data and driving parameter data of the vehicle; determining the power required for vehicle limp-home driving according to the driving state data and driving parameter data. The input variables and output variables are set to establish a membership function, wherein the input variables include the accelerator pedal opening, the battery SOC value and the slope, and the output variables include the power limitation factor of limp-home driving; a fuzzy control rule table is created according to the membership function, and the output variables are de-fuzzified according to the fuzzy control rule table and the weighted average method to obtain the power limitation factor of limp-home driving; the vehicle demand power is determined according to the actual engine speed, the engine transmission ratio and the vehicle demand torque; and the power required for vehicle limp-home driving is determined according to the power limitation factor and the vehicle demand power.

[0005] However, the existing technical solution does not consider the power consumption state of multiple controllers in the vehicle in the limp-home state, resulting in inaccurate power demand calculation, which may not meet the power demand in the limp-home state. SUMMARY

[0006] To solve the above problems in the prior art, in a first aspect, embodiments of the present application provide a method for determining power supply capacity requirement based on limp-home of vehicle failure, the method comprising: obtaining working current of each load of a basic power chassis low-voltage load type of a vehicle; obtaining working current of each load of a basic regulation requirement load type of the vehicle; obtaining basic current of each load of a comfort function load type of the vehicle; calculating a sum of the working current of each load of the basic power chassis low-voltage load type, the working current of each load of the basic regulation requirement load type, and the basic current of each load of the comfort function load type as total load current; determining limp-home starting electric quantity according to residual electric quantity of a vehicle battery during driving; obtaining limp-home stopping electric quantity according to vehicle battery attributes; and determining low-voltage power supply capacity requirement value based on limp-home of vehicle failure according to limp-home time, the total load current, the limp-home starting electric quantity, and the limp-home stopping electric quantity.

[0007] In some embodiments, obtaining the limp-home stopping electric quantity according to the vehicle battery attributes comprises: determining the limp-home stopping electric quantity according to a lowest critical residual electric quantity of the vehicle battery.

[0008] In some embodiments, the low-voltage power supply capacity requirement value is positively correlated with the limp-home time and the total load current, and is negatively correlated with a difference between the limp-home starting electric quantity and the limp-home stopping electric quantity.

[0009] In some embodiments, the basic current of each load of the comfort function load type comprises standby current or function degradation current.

[0010] In some embodiments, the limp-home time is determined according to the following steps: obtaining statistical data of a predetermined number of driving distances from vehicle failure to a repair point from cloud data; determining effective distance according to the statistical data; and determining the limp-home time according to the effective distance and a driving speed under limp-home working conditions of the vehicle.

[0011] In some embodiments, determining the effective distance according to the statistical data comprises: selecting, from the statistical data, data of driving distances less than a distance threshold as selected driving distance data; and performing average value calculation on the selected driving distance data to obtain the effective distance.

[0012] In some embodiments, the loads of the basic power chassis low-voltage load type comprise one or more of the following: brake-related controllers, motors, pumps, valves; steering-related controllers, motors, pumps, valves; low-voltage side parts of drive motor controllers; and low-voltage side parts of battery energy management controllers.

[0013] In some embodiments, the base regulation demand load type of loads comprises one or more of the following: vehicle light, wiper motor and its sensing actuator; vehicle window motor and its sensing actuator; door lock motor; seat adjustment controller; combination meter; gear shift system.

[0014] In some embodiments, the comfort function load type of loads comprises one or more of the following: seat massage, heating, ventilation related controller actuator; rear window, outside mirror, steering wheel heating related controller and actuator; ambient light controller and actuator; intelligent driving related radar, camera sensor and actuator.

[0015] In a second aspect, embodiments of the present application provide a vehicle limp-home based power demand determination device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer program, when executed by the processor, implements the vehicle limp-home based power demand determination method described in any of the above embodiments.

[0016] The vehicle limp-home based power demand determination method and device provided by embodiments of the present application complete vehicle fault state electrical load working condition analysis by counting the working demand, degradation and function shutdown of each part during vehicle fault, and complete power demand calculation based on the analysis result. The power demand calculation scheme provided by the present application comprehensively considers the DC / DC converter fault limp-home condition, the SOC selection principle is strict, the power demand calculation is accurate, fully meets the energy consumption demand under the limp-home condition, and can guarantee the safe driving of the vehicle and the service life of the storage battery. BRIEF DESCRIPTION OF DRAWINGS

[0017] The above and other objects, features and advantages of embodiments of the present application will become more apparent from the following detailed description read in conjunction with the accompanying drawings. In the drawings, several embodiments of the present application are illustrated by way of example in which:

[0018] Figure 1 A flowchart of a vehicle limp-home based power demand determination method according to embodiments of the present application is shown.

[0019] In the drawings, identical or corresponding reference signs indicate identical or corresponding parts. DETAILED DESCRIPTION

[0020] The principles and spirits of the present application will be described below with reference to several exemplary embodiments. It should be understood that these embodiments are given only to enable those skilled in the art to better understand and implement the present application, and do not limit the scope of the present application in any way.

[0021] In one aspect, embodiments of the present application provide a limp-home based power demand determination method for a vehicle. Referring to Figure 1 FIG. 1 shows a flowchart of a limp-home based power demand determination method according to an embodiment of the present application. The method comprises steps S101-S107.

[0022] In step S101, an operating current of each load of a basic powertrain low voltage load type of the vehicle is acquired.

[0023] As an embodiment of the present application, the loads of the basic powertrain low voltage load type can include one or more of the following: brake related controller, motor, pump, valve; steering related controller, motor, pump, valve; drive motor controller low voltage side portion; battery energy management controller low voltage side portion.

[0024] In step S102, an operating current of each load of a basic regulation requirement load type of the vehicle is acquired.

[0025] As an embodiment of the present application, the loads of the basic regulation requirement load type can include one or more of the following: vehicle light, wiper motor and its sensing actuator; window motor and its sensing actuator; door lock motor; seat adjustment controller; combination meter; gear shifting system.

[0026] In step S103, a basic current of each load of a comfort function load type of the vehicle is acquired. As an embodiment of the present application, the basic current of each load of the comfort function load type includes a standby current or a function degraded current.

[0027] As an embodiment of the present application, the loads of the comfort function load type can include one or more of the following: seat massage, heating, ventilation related controller actuator; rear window, outside rearview mirror, steering wheel heating related controller and actuator; ambient light controller and actuator; intelligent driving related radar, camera sensor and actuator.

[0028] The basic powertrain low voltage load and the basic regulation requirement load both use operating currents to ensure normal operation. In a fault limp-home scenario, the comfort function can be turned off or degraded, and the comfort function load works with a standby current or a function degraded current.

[0029] An example scenario of the standby current is that the comfort function load is connected to the vehicle constant power, cannot be powered off and does not drive any other actuator sensor to work, and only maintains a woken-up working state, at which time the load is in a standby working state, and the current at this time is the standby current. For example, the ambient light controller does not drive the ambient light current, but the controller itself still needs a standby current to keep the open state.

[0030] An example scenario of the function-reduced current is that: a comfort function load is connected to the whole vehicle power supply, cannot be powered off, and needs to drive other actuators or sensors to work, and the power value of the actuator sensor working is less than the power value when the whole vehicle is running, at this time, the load is in a degraded working state, and the current at this time is the function degradation current. For example, the car machine large screen, when the function is degraded, the brightness of the car machine large screen is reduced and part of the entertainment operation is disabled, and the current at this time is the function degradation current.

[0031] As an example, to ensure that the basic power chassis low-voltage load works normally, the total working current of all loads in the basic power chassis low-voltage load is I b , unit: A. The total working current of all loads in the basic regulation required load is I l , unit: A. The total basic current of all loads in the comfort function load is I c , unit: A.

[0032] In step S104, the sum of the working current of each load of the basic power chassis low-voltage load type, the working current of each load of the basic regulation required load type, and the basic current of each load of the comfort function load type is calculated as the total load current. In combination with the example above, the total load current I total =I b +I l +I c , wherein I b is the total working current of all loads of the basic power chassis low-voltage load type, I l is the total working current of all loads of the basic regulation required load type, and I c is the total basic current of all loads of the comfort function load type.

[0033] In step S105, the limp-starting amount of electricity is determined according to the remaining amount of electricity of the vehicle battery during running, that is, the amount of electricity of the low-voltage battery in the low-voltage power supply system at the moment when the vehicle starts to limp. In this paper, the amount of electricity can also be referred to as the remaining amount of electricity, which can be represented by SOC (State Of Charge, percentage of remaining amount of electricity), for example. For example, the limp-starting amount of electricity can be represented by SOCstart.

[0034] As an example, SOCstart can be determined by the following method: the SOC value of the vehicle battery during running is extracted through vehicle data burying, and the average value of all data is taken as SOCstart.

[0035] In step S106, the limp-stopping amount of electricity is obtained according to the vehicle battery attribute, that is, the amount of electricity of the low-voltage battery in the low-voltage power supply system at the moment when the vehicle ends to limp. For example, the limp-stopping amount of electricity can be represented by SOCstop.

[0036] As an embodiment of the present application, acquiring limp-home stopping electric quantity according to vehicle battery attribute can include: determining the limp-home stopping electric quantity according to the minimum critical residual electric quantity of the vehicle battery.

[0037] In this embodiment, the limp-home stopping electric quantity SOCstop selects a more stringent condition, that is, the minimum SOC value that the battery can reach during driving, that is, the critical SOC value of the low-voltage battery of the whole vehicle, that is, SOCstop=SOCmin. This value is related to the attribute of the battery and is the attribute of the battery itself obtained by calibration. In the case of fixed vehicle type and fixed selection of 12V battery, the minimum SOC value that can be allowed to reach is usually fixed.

[0038] In step S107, the low-voltage power supply capacity demand value based on vehicle failure limp-home is determined according to the limp-home time T, the total load current, the limp-home starting electric quantity, and the limp-home stopping electric quantity.

[0039] As an embodiment of the present application, the limp-home time T can be determined according to the following steps: acquiring statistical data of a predetermined number of driving distances from vehicle failure to a repair point from cloud data; determining an effective distance according to the statistical data; and determining the limp-home time according to the effective distance and the vehicle limp-home operating speed.

[0040] As an embodiment of the present application, determining the effective distance according to the statistical data can include: selecting data with a driving distance less than a distance threshold value from the statistical data as selected driving distance data; and performing average value calculation on the selected driving distance data to obtain the effective distance.

[0041] For example only, the limp-home time T is determined by the following method: 100 vehicles are extracted from the cloud data of the host factory, and the driving distance of the vehicle from the vehicle failure to the repair factory or 4S shop is obtained from the cloud. The distance calculation basis is: the distance driven by the vehicle from the vehicle failure to the vehicle failure recovery. Only the data with a distance less than 20 km is extracted as effective data. The average value of the effective data of 100 vehicles is calculated to obtain the effective L, which is km. The general vehicle limp-home operating speed is between 30-50 km / h, and the middle value 40 km / h is taken, that is, the limp-home speed Sl. The limp-home time T is calculated as L / Sl, which is hours.

[0042] As an embodiment of the present application, the low-voltage power supply capacity demand value is positively correlated with the limp-home time and the total load current, and is negatively correlated with the difference between the limp-home starting electric quantity and the limp-home stopping electric quantity.

[0043] For example only, the low-voltage power supply capacity demand value can be calculated according to the following formula: Q=((I b +Il +I c )*T) / (SOCstart-SOCstop). Wherein Q is the low-voltage power supply capacity requirement value, unit is ampere-hour (Ah), I b is the total working current of all loads of the basic power chassis low-voltage load type, I l is the total working current of all loads of the basic regulation requirement load type, I c is the total basic current of all loads of the comfort function load type, T is the limp time, unit is h, SOCstart is the limp start electric quantity, and SOCstop is the limp stop electric quantity.

[0044] In another aspect, the embodiments of the present application provide a power supply requirement determination device based on vehicle fault limp, which comprises a memory and a processor, and the memory stores a computer program which, when executed by the processor, implements the power supply requirement determination method based on vehicle fault limp described in any of the above embodiments.

[0045] The power supply requirement determination method and device based on vehicle fault limp provided by the embodiments of the present application complete the analysis of the working conditions of the electrical loads in the vehicle fault state through the statistics of the working requirements, degradation and function shutdown of each part in the vehicle fault process, and complete the power supply requirement calculation based on the analysis results. The power supply requirement calculation scheme provided by the present application comprehensively considers the DC / DC converter fault limp condition, the calculation SOC selection principle is strict, the power supply requirement calculation is accurate, the energy consumption requirement under the limp condition is fully met, and the vehicle safe driving and the service life of the storage battery are guaranteed.

[0046] The foregoing description of the embodiments of the present application has been given for illustrative purposes only and is not exhaustive or limited to the precise forms disclosed. It will be understood by those skilled in the art that various changes can be made and equivalents substituted for elements thereof without departing from the scope of the present application. In addition, many modifications can be made to adapt a particular situation or material to the teachings of the present application without departing from the central scope thereof. Therefore, the present application is not intended to be limited to the particular embodiments disclosed as the best mode contemplated for carrying out the present application, and includes all embodiments falling within the scope of the appended claims.

Claims

1. A method for determining power demand based on vehicle limpness due to fault, characterized in that, The method includes: Obtain the operating current of each load of the vehicle's basic power chassis low-voltage load type; Obtain the operating current of each load type for the vehicle's basic regulatory requirements; Obtain the base current for each load of the vehicle's comfort function load type; Calculate the sum of the operating current of each load of the basic power chassis low-voltage load type, the operating current of each load of the basic regulatory requirement load type, and the basic current of each load of the comfort function load type, as the total load current; The limp-start charge is determined based on the remaining charge in the vehicle's battery during driving. Obtain the limp-stop charge level based on the vehicle's battery properties; Based on the limp-out time, the total load current, the limp-out start charge, and the limp-out stop charge, determine the low-voltage power supply capacity requirement for vehicle limp-out due to vehicle fault. The basic power chassis low-voltage load type includes one or more of the following: brake-related controllers, motors, pumps, and valves; steering-related controllers, motors, pumps, and valves; the low-voltage side of the drive motor controller; and the low-voltage side of the battery energy management controller. The load types required by the basic regulations include one or more of the following: vehicle lights, wiper motors and their sensing actuators; window motors and their sensing actuators; door lock motors; seat adjustment controllers; instrument clusters; and gear shifting systems.

2. The method for determining power demand based on vehicle limpness according to claim 1, characterized in that, The limp-out charge level determined based on the vehicle battery properties includes: The limp-stop charge level is determined based on the minimum critical remaining charge of the vehicle battery.

3. The method for determining power demand based on vehicle limpness according to claim 1, characterized in that, The low-voltage power supply capacity requirement is positively correlated with the limp time and the total load current, and negatively correlated with the difference between the limp start charge and the limp stop charge.

4. The method for determining power demand based on vehicle limpness according to claim 1, characterized in that, The base current for each load of the comfort function load type includes standby current or function degradation current.

5. The method for determining power demand based on vehicle limpness according to any one of claims 1-4, characterized in that, The limp time is determined according to the following steps: Obtain statistical data from cloud data on the distance traveled to repair shops after a predetermined number of vehicle breakdowns; The effective distance is determined based on the statistical data. The limp time is determined based on the effective distance and the vehicle's limp speed.

6. The method for determining power demand based on vehicle limpness according to claim 5, characterized in that, Determining the effective distance based on the aforementioned statistical data includes: Select data whose driving distance is less than the distance threshold from the statistical data, and use these data as the selected driving distance data; The effective distance is obtained by averaging the selected driving distance data.

7. The method for determining power demand based on vehicle limpness according to any one of claims 1-4, characterized in that, The comfort function load type includes one or more of the following: controllers and actuators related to seat massage, heating, and ventilation; controllers and actuators related to rear window, exterior rearview mirror, and steering wheel heating; ambient lighting controllers and actuators; and sensors and actuators related to intelligent driving radar and cameras.

8. A power demand determination device based on vehicle limp-out due to vehicle malfunction, characterized in that, The device includes a memory and a processor, wherein the memory stores a computer program that, when executed by the processor, implements the power demand determination method based on vehicle limpness as described in any one of claims 1-7.

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