CN113733928A - Vehicle control method and device, control equipment and automobile - Google Patents

Vehicle control method and device, control equipment and automobile Download PDF

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Publication number
CN113733928A
CN113733928A CN202010461736.4A CN202010461736A CN113733928A CN 113733928 A CN113733928 A CN 113733928A CN 202010461736 A CN202010461736 A CN 202010461736A CN 113733928 A CN113733928 A CN 113733928A
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battery
vehicle
discharge power
torque
target
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CN113733928B (en
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张小帅
梁海强
储琦
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Beijing Electric Vehicle Co Ltd
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Beijing Electric Vehicle Co Ltd
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L15/00—Methods, circuits, or devices for controlling the traction-motor speed of electrically-propelled vehicles
    • B60L15/20—Methods, circuits, or devices for controlling the traction-motor speed of electrically-propelled vehicles for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
    • B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2240/00—Control parameters of input or output; Target parameters
    • B60L2240/10—Vehicle control parameters
    • B60L2240/12—Speed
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2240/00—Control parameters of input or output; Target parameters
    • B60L2240/40—Drive Train control parameters
    • B60L2240/42—Drive Train control parameters related to electric machines
    • B60L2240/423—Torque
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L2240/00—Control parameters of input or output; Target parameters
    • B60L2240/40—Drive Train control parameters
    • B60L2240/54—Drive Train control parameters related to batteries
    • B60L2240/545—Temperature
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/70—Energy storage systems for electromobility, e.g. batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/72—Electric energy management in electromobility

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Electric Propulsion And Braking For Vehicles (AREA)

Abstract

The invention provides a control method, a control device, control equipment and an automobile of a vehicle, wherein the control method comprises the following steps: acquiring a vehicle running state of a target vehicle; determining a target torque according to the vehicle running state; sending the target torque to a Motor Control Unit (MCU) to enable a motor to output the target torque; wherein the vehicle operating state includes an accelerator opening degree, a vehicle speed, and a temperature change rate of a battery. According to the scheme, the discharge power of the battery is processed, so that the test requirements can be met, and the driving performance is improved; uncomfortable driving experience caused by dynamic fluctuation when the vehicle accelerates at the full throttle or climbs a slope in the running process in a high-temperature environment can be avoided; in addition, the temperature change rate is introduced to carry out torque limiting treatment on the over-temperature working condition in advance, so that the condition of overhigh battery temperature is avoided, and the safety of the vehicle battery is protected.

Description

Vehicle control method and device, control equipment and automobile
Technical Field
The invention relates to the field of automobiles, in particular to a vehicle control method, a vehicle control device, vehicle control equipment and an automobile.
Background
According to the highest speed test requirement in GB/T18385 and 2005 electric automobile power performance test method, the highest speed of the vehicle under the full throttle working condition is stable. However, due to the battery characteristics, when the battery operates at the maximum power, the vehicle speed may not meet the requirement, that is, when the accelerator is full during the test, the battery discharge power may fluctuate due to fluctuation of the battery temperature, so that the vehicle speed fluctuates, and finally the test requirement of vehicle speed stability cannot be met.
In addition, when the vehicle starts the track mode, the vehicle has a high-power battery discharge requirement, and the battery is required to meet the conditions of allowing to instantly discharge larger power and ensuring the thermal balance of the battery.
Disclosure of Invention
The embodiment of the invention provides a vehicle control method, a vehicle control device, vehicle control equipment and a vehicle, which are used for solving the problem of unstable vehicle speed of an electric vehicle caused by battery thermal balance in the prior art.
In order to solve the technical problems, the invention adopts the following technical scheme:
according to an aspect of the present invention, there is provided a control method of a vehicle, including:
acquiring a vehicle running state of a target vehicle;
determining a target torque according to the vehicle running state;
sending the target torque to a Motor Control Unit (MCU) to enable a motor to output the target torque;
wherein the vehicle operating state includes an accelerator opening degree, a vehicle speed, and a temperature change rate of a battery.
Optionally, the determining a target torque according to the vehicle running state includes:
determining the required torque of the target vehicle according to the opening degree of the accelerator pedal and the vehicle speed, and determining a torque limit coefficient corresponding to the current temperature change rate of the battery of the target vehicle according to the corresponding relation between the temperature change rate of the battery and the torque limit coefficient;
and determining the target torque according to the torque limiting coefficient and the required torque.
Optionally, the determining a target torque according to the vehicle running state includes:
acquiring the currently allowed maximum discharge power of a battery of the target vehicle; wherein the maximum discharge power is calculated by a Battery Management System (BMS) according to the battery operating state of the target vehicle;
when the opening degree of the accelerator pedal is larger than or equal to a preset opening value, judging whether a first mode of the target vehicle is started or not;
if the first mode is not started, controlling the battery discharge power of the target vehicle not to exceed the maximum discharge power;
and determining a target torque according to the opening degree of the accelerator pedal, the battery discharge power and the battery working state.
Optionally, the battery operating state includes a battery temperature, a cell voltage, and a state of charge SOC.
Optionally, the first mode comprises a track mode.
Optionally, the control method further includes:
adjusting the maximum discharge power every preset time according to the corresponding relation between the maximum discharge power and time;
wherein the adjusted maximum discharge power is less than the maximum discharge power before adjustment.
Optionally, the method further comprises:
when the working condition of the vehicle changes, stopping controlling the discharge power of the battery;
the change of the vehicle working condition comprises the change rate of the opening degree of an accelerator pedal exceeding a preset value, gear switching and mode switching.
According to another aspect of the present invention, there is provided a control apparatus of a vehicle, including:
the data acquisition module is used for acquiring the vehicle running state of the target vehicle;
the torque determination module is used for determining a target torque according to the vehicle running state;
the torque transmitting module is used for transmitting the target torque to the motor control unit MCU so that the motor outputs the target torque;
wherein the vehicle operating state includes an accelerator opening degree, a vehicle speed, and a temperature change rate of a battery.
According to another aspect of the present invention, there is provided a control apparatus comprising a memory, a processor, and a program stored on the memory and executable on the processor; the processor implements the control method as described above when executing the program.
According to another aspect of the present invention, there is provided an automobile including the control apparatus as described above.
The invention has the beneficial effects that:
according to the scheme, the discharge power of the battery is processed, so that the test requirements can be met, and the driving performance is improved; uncomfortable driving experience caused by dynamic fluctuation when the vehicle accelerates at the full throttle or climbs a slope in the running process in a high-temperature environment can be avoided; in addition, the temperature change rate is introduced to carry out torque limiting treatment on the over-temperature working condition in advance, so that the condition of overhigh battery temperature is avoided, and the safety of the vehicle battery is protected.
Drawings
FIG. 1 is a schematic diagram illustrating a method for controlling thermal balance of a battery according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a control apparatus for thermal balancing of a battery according to an embodiment of the present invention;
FIG. 3 is a system block diagram illustrating a thermal balance control of a battery according to an embodiment of the present invention;
fig. 4 is a flowchart illustrating a battery discharge power process performed in the control method for battery thermal balance according to the embodiment of the present invention;
fig. 5 is a flowchart illustrating torque limitation by a temperature change rate in a method for controlling a thermal balance of a battery according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.
The invention provides a vehicle control method, a vehicle control device and a vehicle, aiming at the problem of unstable vehicle speed of an electric vehicle caused by thermal balance of a battery.
As shown in fig. 1, one embodiment of the present invention provides a control method for a vehicle, including:
s11: acquiring a vehicle running state of a target vehicle;
s12: determining a target torque according to the vehicle running state;
s13: and sending the target torque to a Motor Control Unit (MCU) so that the motor outputs the target torque.
It should be noted that, in order to solve the problem of battery discharge power fluctuation caused by battery thermal balance, a Vehicle Control Unit (VCU) may determine output of battery discharge power at this time according to the Vehicle operating state (i.e., the opening degree of an accelerator pedal and other signal inputs of the Vehicle), determine a target torque finally, and output the target torque to a Motor Control Unit (MCU). Optionally, the vehicle operating state includes an accelerator opening, a vehicle speed, and a temperature change rate of a battery.
That is, the target torque may be determined by the vehicle operating state for the purpose of controlling the vehicle speed.
Wherein, the following two schemes can be adopted for control: firstly, the discharge power of the battery is controlled, so that the discharge power of the battery can only be reduced and cannot be increased under certain conditions, and the problem of thermal balance of the battery is avoided; and secondly, carrying out torque limitation according to the temperature change rate of the battery so as to ensure the thermal balance of the battery.
Specifically, according to an embodiment of the present invention, the determining the target torque according to the vehicle operation state includes:
determining the required torque of the target vehicle according to the opening degree of the accelerator pedal and the vehicle speed, and determining a torque limit coefficient corresponding to the current temperature change rate of the battery of the target vehicle according to the corresponding relation between the temperature change rate of the battery and the torque limit coefficient;
and determining the target torque according to the torque limiting coefficient and the required torque.
It should be noted that, the corresponding relationship between the temperature change rate of the battery and the torque limiting coefficient can be obtained through a whole vehicle experiment to form a relationship table, so that the maximum temperature change rate of the battery is utilized to limit the torque. That is, it is possible to ensure the thermal balance of the battery by performing torque limitation on the temperature rise of the battery when the battery is over-temperature, that is, when the temperature change rate of the battery (battery temperature rise rate) is high. Specifically, the VCU can be used for determining a target torque after adjusting the torque, and then outputting the target torque to the motor to avoid overlarge output power, thereby avoiding the battery from being over-temperature and further avoiding the fluctuation of the vehicle speed.
As shown in fig. 5, the temperature change rate of the battery may be calculated by a first formula:
Figure BDA0002511174730000041
where Δ T represents the rate of change of temperature of the battery, TtRepresenting a temperature value at time t; t ist-1Representing the temperature value at the time t-1; dt represents the time interval between time t and time t-1.
And looking up a table (namely the relation table) according to the delta T to obtain a torque limiting coefficient (namely a torque limiting coefficient), and sending the product of the torque limiting coefficient and the required torque to the motor as a target torque for execution.
In addition, for a battery product in which the battery temperature is greatly affected by the environment, the battery temperature also affects the magnitude of the energy recovery torque, and may bring about a bad driving experience such as vehicle shrugging during recovery. Therefore, the feedback power of the battery can be controlled under the working condition of energy recovery, even if the strategy of taking small feedback power of the battery is adopted, the feedback power of the battery is only allowed to be reduced and cannot be increased, and the control of taking small feedback power of the battery is stopped after the working condition of energy recovery exits.
By the method, when the temperature of the battery rises too fast, the torque can be limited through the temperature change rate of the battery, and therefore the purpose of controlling the thermal balance of the battery is achieved.
According to another embodiment of the present invention, the determining a target torque according to the vehicle running state includes:
acquiring the currently allowed maximum discharge power of a battery of the target vehicle; wherein the maximum discharge power is calculated by a Battery Management System (BMS) according to the battery operating state of the target vehicle;
when the opening degree of the accelerator pedal is larger than or equal to a preset opening value, judging whether a first mode of the target vehicle is started or not;
if the first mode is not started, controlling the battery discharge power of the target vehicle not to exceed the maximum discharge power;
and determining a target torque according to the opening degree of the accelerator pedal, the battery discharge power and the battery working state.
Optionally, the first mode comprises a track mode.
It should be noted that, as shown in fig. 3, the maximum discharge power allowed by the Battery may be output to the VCU by a Battery Management System (BMS), where the maximum discharge power is calculated by the BMS according to the Battery operating state of the target vehicle, and optionally, the Battery operating state includes a Battery temperature, a Battery cell voltage, and a state of charge SOC. That is, the maximum discharge power may vary according to the battery operating state, and the BMS may update the maximum discharge power according to the variation of the battery operating state.
According to one embodiment of the present invention, the VCU may detect a vehicle running condition, and control the allowable battery discharging power when the accelerator pedal opening is greater than or equal to a preset opening value, for example, when the accelerator pedal opening is greater than or equal to 95% (the running condition at this time may be regarded as full throttle running). The preset opening value can be obtained by calibration according to actual conditions; further, due to the large battery discharge power required by the vehicle in some special modes (i.e., the first mode), such as the racing mode, the vehicle operation mode needs to be determined for the difference processing.
Specifically, according to one embodiment of the present invention, the battery discharging power can be processed according to the battery discharging power processing flow chart shown in fig. 4, so as to achieve the purpose of controlling the thermal balance of the battery:
s41: starting;
s42: judging whether the current gear of the vehicle is a driving gear, if so, executing S44; otherwise, go to S43;
s43: controlling the discharge power output of the battery to be 0;
s44: judging whether the opening degree of the accelerator pedal is greater than or equal to 95%, if yes, executing S46; otherwise, go to S45;
s45: the battery discharge power is normally output, namely the battery discharge power is not specially processed;
s46: judging whether the track mode is started, if so, executing S48; otherwise, go to S47;
s47: the battery discharge power is not allowed to be increased in output;
s48: the battery discharge power is instantly amplified and output;
s49: and (6) ending.
That is, when the opening degree of the accelerator pedal is greater than or equal to 95% and the racing track mode is not started, the battery discharge power is controlled to only allow the battery to fall and not to allow the battery to rise, so that the purposes of battery thermal balance and no vehicle speed fluctuation in the hill climbing test are achieved. On the other hand, when the opening degree of the accelerator pedal is greater than or equal to 95% and the track mode is started, the current battery discharge power is allowed to output larger power so as to meet the requirement of the vehicle on larger battery discharge power in the track mode.
The control method is characterized in that the control method controls the discharge power of the battery to only allow the reduction and not to allow the rise, and can also be realized by the following steps:
optionally, the control method further includes: adjusting the maximum discharge power every preset time according to the corresponding relation between the maximum discharge power and time; wherein the adjusted maximum discharge power is less than the maximum discharge power before adjustment.
That is, when the accelerator pedal opening is greater than or equal to 95%, that is, when the vehicle is operating at full throttle, it is necessary to adjust the maximum discharge power at intervals of a preset time to control the battery discharge power to be gradually decreased, so that the effect of allowing only the decrease and not allowing the increase is achieved, thereby controlling the battery heat balance. Specifically, the corresponding relationship between the maximum discharge power and the time can be obtained according to an experiment, that is, how long the maximum discharge power of a certain value is allowed to be maintained without causing a certain influence on the vehicle speed fluctuation, and the corresponding time is taken as the preset time, that is, the preset time can be calibrated according to an actual situation. When the holding-permitted period is reached, reduction control of the maximum discharge power is required to control the battery discharge power output of the vehicle.
In addition, the preset duration can be displayed on an instrument in a countdown mode to prompt a driver, and the current battery discharging power can be kept for a long time, so that the driver can prepare for a certain idea for controlling the reduction of the battery discharging power by the vehicle, and the driving experience can be improved.
Accordingly, similar control can be performed on the vehicle under the starting condition of the track mode, so that the problem of battery heat balance is avoided. Specifically, in the track mode, the instantaneous power of the battery is large, the BMS can calculate the time of high-power stable output and output the time to the VCU, and the VCU outputs the time signal to the instrument. This time will gradually decrease when the battery thermal balance does not allow the battery management unit to output such a large power until the transition to the normal output power state. That is, in the track mode, the battery discharge power is allowed to be instantly amplified, and the battery discharge power can be reduced and controlled after the vehicle runs for a period of time with high power, so as to prevent the heat balance of the battery from being in problem.
In summary, according to the requirements of the GB/T18385-2005 electric vehicle power performance test method, the battery discharge power processing strategy provided by the embodiment of the invention can be used when the highest vehicle speed test is performed, that is, the battery power is only allowed to decrease but not to increase under the full throttle working condition, so as to ensure the stability of the vehicle speed.
Optionally, the control method further includes:
when the working condition of the vehicle changes, stopping controlling the discharge power of the battery;
the change of the vehicle working condition comprises the change rate of the opening degree of an accelerator pedal exceeding a preset value, gear switching and mode switching.
It should be noted that, in order to avoid insufficient power caused by failure of power recovery after power is reduced in other operating conditions, a recovery strategy after battery discharge power processing may be set, which mainly includes a recovery strategy set according to a change of an accelerator pedal and a change of an operating condition, for example, the battery discharge power may be allowed to recover when the accelerator pedal is released.
Specifically, the recovery condition after the battery discharge power is allowed to be processed may be set as: when the accelerator pedal opening is changed, the battery discharge power is recovered, and it should be noted that, here, the amplitude of the change of the accelerator pedal opening may be limited according to specific situations, for example, the battery discharge power is recovered when 50% of the change occurs; or the battery discharge power is allowed to recover when the vehicle working condition changes, wherein the vehicle working condition changes comprise gear switching or mode switching, driving and recovery switching and the like.
That is, the situation of insufficient power caused by the fact that the power cannot be recovered after the power is reduced can be avoided through the arrangement.
It is worth mentioning that when the battery characteristics are different (no matter the battery is a liquid-cooled battery or an air-cooled battery), the battery temperature fluctuation conditions are different, and the control method provided by the embodiment of the invention can enable the vehicle to meet the highest speed requirement of GB T18385 and 2005 electric vehicle power performance test method under working conditions of high temperature and high load, and the like, and can avoid the occurrence of the vehicle recess phenomenon, thereby ensuring the driving experience. In addition, because the battery temperature and the battery power have a direct relationship, the processing strategy of the battery power can also be realized by processing the battery temperature.
In the embodiment of the invention, the discharge power of the battery is processed, so that the test requirement can be met, and the driving performance is improved; uncomfortable driving experience caused by dynamic fluctuation when the vehicle accelerates at the full throttle or climbs a slope in the running process in a high-temperature environment can be avoided; in addition, the temperature change rate is introduced to carry out torque limiting treatment on the over-temperature working condition in advance, so that the condition of overhigh battery temperature is avoided, and the safety of the vehicle battery is protected.
As shown in fig. 2, an embodiment of the present invention further provides a control apparatus for a vehicle, including:
a data acquisition module 21 for acquiring a vehicle running state of a target vehicle;
the torque determination module 22 is used for determining a target torque according to the vehicle running state;
and the torque transmitting module 23 is configured to transmit the target torque to the motor control unit MCU, so that the motor outputs the target torque.
It should be noted that, in order to solve the problem of battery discharge power fluctuation caused by battery thermal balance, the VCU may determine the output of the battery discharge power at this time according to the vehicle operating state (i.e., the opening degree of the accelerator pedal and other signal inputs of the entire vehicle), and finally determine the target torque, and then output the target torque to the MCU. Optionally, the vehicle operating state includes an accelerator opening, a vehicle speed, and a temperature change rate of a battery.
That is, the target torque may be determined by the vehicle operating state for the purpose of controlling the vehicle speed.
Wherein, the following two schemes can be adopted for control: firstly, the discharge power of the battery is controlled, so that the discharge power of the battery can only be reduced and cannot be increased under certain conditions, and the problem of thermal balance of the battery is avoided; and secondly, carrying out torque limitation according to the temperature change rate of the battery so as to ensure the thermal balance of the battery.
Specifically, according to one embodiment of the present invention, the torque determination module 22 includes:
the power determining unit is used for determining the required torque of the target vehicle according to the opening degree of the accelerator pedal and the vehicle speed, and determining a torque limit coefficient corresponding to the current temperature change rate of the battery of the target vehicle according to the corresponding relation between the temperature change rate of the battery and the torque limit coefficient;
and the first torque unit is used for determining the target torque according to the torque limiting coefficient and the required torque.
It should be noted that, the corresponding relationship between the temperature change rate of the battery and the torque limiting coefficient can be obtained through a whole vehicle experiment to form a relationship table, so that the maximum temperature change rate of the battery is utilized to limit the torque. That is, it is possible to ensure the thermal balance of the battery by performing torque limitation on the temperature rise of the battery when the battery is over-temperature, that is, when the temperature change rate of the battery (battery temperature rise rate) is high. Specifically, the VCU can be used for determining a target torque after adjusting the torque, and then outputting the target torque to the motor to avoid overlarge output power, thereby avoiding the battery from being over-temperature and further avoiding the fluctuation of the vehicle speed.
As shown in fig. 5, the temperature change rate of the battery may be calculated by a first formula:
Figure BDA0002511174730000091
where Δ T represents the rate of change of temperature of the battery, TtRepresenting a temperature value at time t; t ist-1Representing the temperature value at the time t-1; dt represents the time interval between time t and time t-1.
And looking up a table (namely the relation table) according to the delta T to obtain a torque limiting coefficient (namely a torque limiting coefficient), and sending the product of the torque limiting coefficient and the required torque to the motor as a target torque for execution.
In addition, for a battery product in which the battery temperature is greatly affected by the environment, the battery temperature also affects the magnitude of the energy recovery torque, and may bring about a bad driving experience such as vehicle shrugging during recovery. Therefore, the feedback power of the battery can be controlled under the working condition of energy recovery, even if the strategy of taking small feedback power of the battery is adopted, the feedback power of the battery is only allowed to be reduced and cannot be increased, and the control of taking small feedback power of the battery is stopped after the working condition of energy recovery exits.
Through the scheme, when the temperature of the battery rises too fast, the torque can be limited through the change rate of the temperature of the battery, and therefore the purpose of controlling the thermal balance of the battery is achieved.
According to another embodiment of the present invention, the torque determination module 22 includes:
a power determination unit for acquiring a maximum discharge power currently allowed for a battery of the target vehicle; wherein the maximum discharge power is calculated by a Battery Management System (BMS) according to the battery operating state of the target vehicle;
the mode judging unit is used for judging whether a first mode of the target vehicle is started or not when the opening degree of the accelerator pedal is larger than or equal to a preset opening value;
a power control unit, configured to control a battery discharge power of the target vehicle to not exceed the maximum discharge power if the first mode is not turned on;
and the second torque unit is used for determining a target torque according to the opening degree of the accelerator pedal, the battery discharge power and the battery working state.
Optionally, the first mode comprises a track mode.
It should be noted that, as shown in fig. 3, the maximum discharge power allowed by the Battery may be output to the VCU by a Battery Management System (BMS), where the maximum discharge power is calculated by the BMS according to the Battery operating state of the target vehicle, and optionally, the Battery operating state includes a Battery temperature, a Battery cell voltage, and a state of charge SOC. That is, the maximum discharge power may vary according to the battery operating state, and the BMS may update the maximum discharge power according to the variation of the battery operating state.
According to one embodiment of the present invention, the VCU may detect a vehicle running condition, and control the allowable battery discharging power when the accelerator pedal opening is greater than or equal to a preset opening value, for example, when the accelerator pedal opening is greater than or equal to 95% (the running condition at this time may be regarded as full throttle running). The preset opening value can be obtained by calibration according to actual conditions; further, due to the large battery discharge power required by the vehicle in some special modes (i.e., the first mode), such as the racing mode, the vehicle operation mode needs to be determined for the difference processing.
Specifically, according to one embodiment of the present invention, the battery discharging power can be processed according to the battery discharging power processing flow chart shown in fig. 4, so as to achieve the purpose of controlling the thermal balance of the battery:
s41: starting;
s42: judging whether the current gear of the vehicle is a driving gear, if so, executing S44; otherwise, go to S43;
s43: controlling the discharge power output of the battery to be 0;
s44: judging whether the opening degree of the accelerator pedal is greater than or equal to 95%, if yes, executing S46; otherwise, go to S45;
s45: the battery discharge power is normally output, namely the battery discharge power is not specially processed;
s46: judging whether the track mode is started, if so, executing S48; otherwise, go to S47;
s47: the battery discharge power is not allowed to be increased in output;
s48: the battery discharge power is instantly amplified and output;
s49: and (6) ending.
That is, when the opening degree of the accelerator pedal is greater than or equal to 95% and the racing track mode is not started, the battery discharge power is controlled to only allow the battery to fall and not to allow the battery to rise, so that the purposes of battery thermal balance and no vehicle speed fluctuation in the hill climbing test are achieved. On the other hand, when the opening degree of the accelerator pedal is greater than or equal to 95% and the track mode is started, the current battery discharge power is allowed to output larger power so as to meet the requirement of the vehicle on larger battery discharge power in the track mode.
The control method is characterized in that the control method controls the discharge power of the battery to only allow the reduction and not to allow the rise, and can also be realized by the following steps:
optionally, the control device further comprises:
the power adjusting module is used for adjusting the maximum discharge power at intervals of preset time according to the corresponding relation between the maximum discharge power and time; wherein the adjusted maximum discharge power is less than the maximum discharge power before adjustment.
That is, when the accelerator pedal opening is greater than or equal to 95%, that is, when the vehicle is operating at full throttle, it is necessary to adjust the maximum discharge power at intervals of a preset time to control the battery discharge power to be gradually decreased, so that the effect of allowing only the decrease and not allowing the increase is achieved, thereby controlling the battery heat balance. Specifically, the corresponding relationship between the maximum discharge power and the time can be obtained according to an experiment, that is, how long the maximum discharge power of a certain value is allowed to be maintained without causing a certain influence on the vehicle speed fluctuation, and the corresponding time is taken as the preset time, that is, the preset time can be calibrated according to an actual situation. When the holding-permitted period is reached, reduction control of the maximum discharge power is required to control the battery discharge power output of the vehicle.
In addition, the preset duration can be displayed on an instrument in a countdown mode to prompt a driver, and the current battery discharging power can be kept for a long time, so that the driver can prepare for a certain idea for controlling the reduction of the battery discharging power by the vehicle, and the driving experience can be improved.
Accordingly, similar control can be performed on the vehicle under the starting condition of the track mode, so that the problem of battery heat balance is avoided. Specifically, in the track mode, the instantaneous power of the battery is large, the BMS can calculate the time of high-power stable output and output the time to the VCU, and the VCU outputs the time signal to the instrument. This time will gradually decrease when the battery thermal balance does not allow the battery management unit to output such a large power until the transition to the normal output power state. That is, in the track mode, the battery discharge power is allowed to be instantly amplified, and the battery discharge power can be reduced and controlled after the vehicle runs for a period of time with high power, so as to prevent the heat balance of the battery from being in problem.
In summary, according to the requirements of the GB/T18385-2005 electric vehicle power performance test method, the battery discharge power processing strategy provided by the embodiment of the invention can be used when the highest vehicle speed test is performed, that is, the battery power is only allowed to decrease but not to increase under the full throttle working condition, so as to ensure the stability of the vehicle speed.
Optionally, the control device further comprises:
the power recovery module is used for stopping controlling the discharge power of the battery when the working condition of the vehicle changes;
the change of the vehicle working condition comprises the change rate of the opening degree of an accelerator pedal exceeding a preset value, gear switching and mode switching.
It should be noted that, in order to avoid insufficient power caused by failure of power recovery after power is reduced in other operating conditions, a recovery strategy after battery discharge power processing may be set, which mainly includes a recovery strategy set according to a change of an accelerator pedal and a change of an operating condition, for example, the battery discharge power may be allowed to recover when the accelerator pedal is released.
Specifically, the recovery condition after the battery discharge power is allowed to be processed may be set as: when the accelerator pedal opening is changed, the battery discharge power is recovered, and it should be noted that, here, the amplitude of the change of the accelerator pedal opening may be limited according to specific situations, for example, the battery discharge power is recovered when 50% of the change occurs; or the battery discharge power is allowed to recover when the vehicle working condition changes, wherein the vehicle working condition changes comprise gear switching or mode switching, driving and recovery switching and the like.
That is, the situation of insufficient power caused by the fact that the power cannot be recovered after the power is reduced can be avoided through the arrangement.
It is worth mentioning that when the battery characteristics are different (no matter the battery is a liquid-cooled battery or an air-cooled battery), the battery temperature fluctuation conditions are different, and the control device provided by the embodiment of the invention can enable the vehicle to meet the highest speed requirement of GB T18385 and 2005 electric vehicle power performance test method under working conditions of high temperature and high load, and the like, and can avoid the occurrence of the vehicle recess phenomenon, thereby ensuring the driving experience. In addition, because the battery temperature and the battery power have a direct relationship, the processing strategy of the battery power can also be realized by processing the battery temperature.
In the embodiment of the invention, the discharge power of the battery is processed, so that the test requirement can be met, and the driving performance is improved; uncomfortable driving experience caused by dynamic fluctuation when the vehicle accelerates at the full throttle or climbs a slope in the running process in a high-temperature environment can be avoided; in addition, the temperature change rate is introduced to carry out torque limiting treatment on the over-temperature working condition in advance, so that the condition of overhigh battery temperature is avoided, and the safety of the vehicle battery is protected.
The embodiment of the invention also provides control equipment, which comprises a memory, a processor and a program which is stored on the memory and can be operated on the processor; the processor implements the control method as described above when executing the program.
The embodiment of the invention also provides an automobile which comprises the control device.
In the embodiment of the invention, aiming at different battery characteristics, the requirements of GB T18385 and 2005 power performance test method for electric automobiles can be met.
While the preferred embodiments of the present invention have been described, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.

Claims (10)

1. A control method of a vehicle, characterized by comprising:
acquiring a vehicle running state of a target vehicle;
determining a target torque according to the vehicle running state;
sending the target torque to a Motor Control Unit (MCU) to enable a motor to output the target torque;
wherein the vehicle operating state includes an accelerator opening degree, a vehicle speed, and a temperature change rate of a battery.
2. The control method according to claim 1, wherein the determining a target torque according to the vehicle running state includes:
determining the required torque of the target vehicle according to the opening degree of the accelerator pedal and the vehicle speed, and determining a torque limit coefficient corresponding to the current temperature change rate of the battery of the target vehicle according to the corresponding relation between the temperature change rate of the battery and the torque limit coefficient;
and determining the target torque according to the torque limiting coefficient and the required torque.
3. The control method according to claim 1, wherein the determining a target torque according to the vehicle running state includes:
acquiring the currently allowed maximum discharge power of a battery of the target vehicle; wherein the maximum discharge power is calculated by a Battery Management System (BMS) according to the battery operating state of the target vehicle;
when the opening degree of the accelerator pedal is larger than or equal to a preset opening value, judging whether a first mode of the target vehicle is started or not;
if the first mode is not started, controlling the battery discharge power of the target vehicle not to exceed the maximum discharge power;
and determining a target torque according to the opening degree of the accelerator pedal, the battery discharge power and the battery working state.
4. The control method of claim 3, wherein the battery operating state comprises battery temperature, cell voltage, and state of charge (SOC).
5. The control method according to claim 3, wherein the first mode includes a track mode.
6. The control method according to claim 3, characterized by further comprising:
adjusting the maximum discharge power every preset time according to the corresponding relation between the maximum discharge power and time;
wherein the adjusted maximum discharge power is less than the maximum discharge power before adjustment.
7. The control method according to claim 3, characterized by further comprising:
when the working condition of the vehicle changes, stopping controlling the discharge power of the battery;
the change of the vehicle working condition comprises the change rate of the opening degree of an accelerator pedal exceeding a preset value, gear switching and mode switching.
8. A control apparatus of a vehicle, characterized by comprising:
the data acquisition module is used for acquiring the vehicle running state of the target vehicle;
the torque determination module is used for determining a target torque according to the vehicle running state;
the torque transmitting module is used for transmitting the target torque to the motor control unit MCU so that the motor outputs the target torque;
wherein the vehicle operating state includes an accelerator opening degree, a vehicle speed, and a temperature change rate of a battery.
9. A control device comprising a memory, a processor, and a program stored on the memory and executable on the processor; characterized in that the processor implements the control method according to any one of claims 1 to 7 when executing the program.
10. A motor vehicle, characterized by comprising the control device according to claim 8.
CN202010461736.4A 2020-05-27 2020-05-27 Control method and device of vehicle, control equipment and automobile Active CN113733928B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114441192A (en) * 2022-01-26 2022-05-06 重庆长安汽车股份有限公司 Method for testing and evaluating heat accumulation and power attenuation of passenger vehicle at normal temperature

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20080089543A (en) * 2007-03-28 2008-10-07 현대자동차주식회사 Cruise control method of hybrid vehicle
CN107472080A (en) * 2016-10-31 2017-12-15 宝沃汽车（中国）有限公司 Method for controlling torque, device and the vehicle of vehicle
CN108162968A (en) * 2016-12-05 2018-06-15 郑州宇通客车股份有限公司 Power output control method and device, power back off control method and device
CN110239361A (en) * 2019-06-12 2019-09-17 国机智骏科技有限公司 Control method, device, entire car controller and the vehicle of Automobile drive power

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20080089543A (en) * 2007-03-28 2008-10-07 현대자동차주식회사 Cruise control method of hybrid vehicle
CN107472080A (en) * 2016-10-31 2017-12-15 宝沃汽车（中国）有限公司 Method for controlling torque, device and the vehicle of vehicle
CN108162968A (en) * 2016-12-05 2018-06-15 郑州宇通客车股份有限公司 Power output control method and device, power back off control method and device
CN110239361A (en) * 2019-06-12 2019-09-17 国机智骏科技有限公司 Control method, device, entire car controller and the vehicle of Automobile drive power

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114441192A (en) * 2022-01-26 2022-05-06 重庆长安汽车股份有限公司 Method for testing and evaluating heat accumulation and power attenuation of passenger vehicle at normal temperature
CN114441192B (en) * 2022-01-26 2023-07-04 重庆长安汽车股份有限公司 Test and evaluation method for heat accumulation and power attenuation of passenger car at normal temperature

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