CN114789660A - Control method and device of electric vehicle and electric vehicle - Google Patents

Control method and device of electric vehicle and electric vehicle Download PDF

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Publication number
CN114789660A
CN114789660A CN202210446503.6A CN202210446503A CN114789660A CN 114789660 A CN114789660 A CN 114789660A CN 202210446503 A CN202210446503 A CN 202210446503A CN 114789660 A CN114789660 A CN 114789660A
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power
motor
power parameter
electric vehicle
parameter
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CN202210446503.6A
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Chinese (zh)
Inventor
李军
杨雪珠
狄忠举
孙承锐
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FAW Group Corp
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FAW Group Corp
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Priority to CN202210446503.6A priority Critical patent/CN114789660A/en
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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
    • B60L3/00—Electric devices on electrically-propelled vehicles for safety purposes; Monitoring operating variables, e.g. speed, deceleration or energy consumption
    • B60L3/0023—Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train
    • B60L3/0061—Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train relating to electrical machines
    • 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
    • B60L3/00—Electric devices on electrically-propelled vehicles for safety purposes; Monitoring operating variables, e.g. speed, deceleration or energy consumption
    • B60L3/0023—Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train
    • 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
    • B60L3/00—Electric devices on electrically-propelled vehicles for safety purposes; Monitoring operating variables, e.g. speed, deceleration or energy consumption
    • B60L3/04—Cutting off the power supply under fault conditions
    • 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
    • B60L2240/42—Drive Train control parameters related to electric machines
    • B60L2240/427—Voltage
    • 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
    • B60L2240/429—Current

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

Abstract

The invention discloses a control method and a control device for an electric vehicle and the electric vehicle. The method comprises the steps of obtaining a required driving power parameter of a motor, a consumed power parameter of a vehicle-mounted electric appliance and a discharge power parameter of a power battery; determining whether the electric vehicle is in a power output abnormal state or not according to the relation among the required driving power parameter, the consumed power parameter and the discharging power parameter; if the electric connection between the power battery and the motor is cut off, the power transmission can still be cut off when the motor is in an uncontrolled fault, namely the power supply of the motor is cut off, so that the motor loses the power output capability, the damage caused by the unexpected acceleration of the electric vehicle is avoided, the physical structure of the electric vehicle is not changed, and the additional cost is not increased.

Description

Control method and device of electric vehicle and electric vehicle
Technical Field
The embodiment of the invention relates to the technical field of electric vehicles, in particular to a control method and device of an electric vehicle and the electric vehicle.
Background
With the popularization of new energy vehicles, the market share rate is on the trend of rising year by year, the occupation ratio in traffic accidents is also increased year by year, and in view of the difference of the new energy vehicles and the traditional fuel vehicles in the power transmission structure: 1) the traditional vehicle is provided with a gearbox clutch, the power connection between an engine and wheels can be cut off, and a motor of the new energy vehicle is directly connected with the wheels; 2) the torque power of the engine of the traditional vehicle is generally not large, the acceleration time of a whole vehicle per hundred kilometers is generally about 8s, the motor of the new energy vehicle has the characteristic of low speed and large torque, and the acceleration time of the whole vehicle per hundred kilometers easily enters 5 s. The unexpected acceleration of the new energy vehicle can cause more serious consequences, and the effective measures that the driver can take are less than those of the traditional vehicle, for example, the driver of the traditional vehicle can switch the neutral gear and physically disconnect the power transmission between the engine and the wheels except for stepping on the brake for deceleration, while the driver of the new energy vehicle can not physically disconnect the power transmission between the motor and the wheels except for stepping on the brake for deceleration.
Most of the existing new energy automobiles output corresponding torque to wheels by controlling a motor controller through a vehicle control unit, so that the purpose of driving the vehicle is achieved, but when the motor fails, the path fails, and only the speed can be reduced by stepping on a brake, so that the safety requirement of the electric vehicle cannot be met.
Therefore, a need exists for a method of shutting off power transmission when motor failure is uncontrolled.
Disclosure of Invention
The invention provides a control method and a control device of an electric vehicle and the electric vehicle, which can still cut off power transmission when a motor fault is uncontrolled and ensure driving safety.
In a first aspect, an embodiment of the present invention provides a control method for an electric vehicle, including:
acquiring a required driving power parameter of a motor, a consumed power parameter of a vehicle-mounted electrical appliance and a discharge power parameter of a power battery;
determining whether the electric vehicle is in a power output abnormal state or not according to the relation among the required driving power parameter, the consumed power parameter and the discharging power parameter;
if yes, the electric connection between the power battery and the motor is cut off.
Optionally, acquiring a required driving power parameter of the motor, a consumed power parameter of the vehicle-mounted electrical appliance, and a discharge power parameter of the power battery, includes:
acquiring a driving intention of a driver, and determining a required driving power parameter of a motor according to the driving intention;
and acquiring the running state of the electric vehicle, and determining the consumed power parameter of the vehicle-mounted electric appliance and the discharge power parameter of the power battery according to the running state.
Optionally, acquiring a driving intention of a driver, and determining a required driving power parameter of the motor according to the driving intention, includes:
acquiring the opening degree of an accelerator pedal;
determining a required torque according to the opening degree of the accelerator pedal;
determining a driving voltage and a driving current according to the required torque;
and determining the required driving power parameter according to the driving voltage and the driving current.
Optionally, obtaining an operating state of the electric vehicle, and determining a consumed power parameter of the vehicle-mounted electrical appliance and a discharge power parameter of the power battery according to the operating state includes:
acquiring a vehicle-mounted electric appliance in an on state in the electric vehicle;
calculating the sum of the powers of the vehicle-mounted electrical appliances in the opening state to obtain the consumed power parameter;
acquiring discharge voltage and discharge current of a power battery;
and determining the discharge power parameter according to the discharge voltage and the discharge current.
Optionally, determining whether the electric vehicle is in a power output abnormal state according to a relationship among the required driving power parameter, the consumed power parameter, and the discharging power parameter includes:
if | P + P 1 -P 2 Determining that the electric vehicle is in | ≧ Δ P for a first preset timeA power output abnormal state;
wherein P represents the required drive power parameter, P 1 Representing said power consumption parameter, P 2 Represents the discharge power parameter, and Δ P represents a safety limit for power output anomalies.
Optionally, before cutting off the electrical connection between the power battery and the electric motor, the method further comprises:
and controlling the motor to reduce the output torque.
Optionally, after controlling the motor to reduce the output torque, the method further includes:
and if the output torque of the motor is greater than a preset threshold value after the second preset time, cutting off the electric connection between the power battery and the motor.
Optionally, the power battery is electrically connected with the electric motor through a high-voltage relay, and the disconnecting the electrical connection between the power battery and the electric motor includes:
and controlling the high-voltage relay to be switched off.
Optionally, the power battery is electrically connected to the motor through a high-voltage relay, and before acquiring a required driving power parameter of the motor, a consumed power parameter of the vehicle-mounted electrical appliance, and a discharging power parameter of the power battery, the method further includes:
judging whether the high-voltage relay is normal or not;
if so, starting the electric vehicle, and acquiring a required driving power parameter of the motor, a consumed power parameter of the vehicle-mounted electric appliance and a discharge power parameter of the power battery;
and if not, prohibiting the electric vehicle from starting.
In a second aspect, an embodiment of the present invention further provides a control apparatus for an electric vehicle, including:
the acquisition module is used for acquiring required driving power parameters of the motor, consumed power parameters of the vehicle-mounted electrical appliance and discharge power parameters of the power battery;
the judging module is used for determining whether the electric vehicle is in a power output abnormal state or not according to the relation among the required driving power parameter, the consumed power parameter and the discharging power parameter;
and the control module is used for cutting off the electric connection between the power battery and the motor when the electric vehicle is determined to be in the abnormal power output state.
In a third aspect, the embodiment of the invention also provides an electric vehicle, which comprises the control device.
The method comprises the steps of obtaining a required driving power parameter of a motor, a consumed power parameter of a vehicle-mounted electric appliance and a discharge power parameter of a power battery; determining whether the electric vehicle is in a power output abnormal state or not according to the relation among the required driving power parameter, the consumed power parameter and the discharging power parameter; if so, the electric connection between the power battery and the motor is cut off, the problem that the electric vehicle in the prior art can only control the motor controller to output corresponding torque to wheels through the vehicle control unit is solved, but when the motor fails, the path fails, only the brake can be stepped on for speed reduction, and the safety requirement of the electric vehicle cannot be met, the power transmission can still be cut off when the motor fails to be controlled, namely, the power supply of the motor is cut off, so that the power output capability of the motor is lost, the damage caused by the unexpected acceleration of the electric vehicle is avoided, the driving safety is ensured, the physical structure of the electric vehicle is not changed, and further, the additional cost cannot be increased.
Drawings
Fig. 1 is a flowchart of a control method for an electric vehicle according to an embodiment of the present invention;
fig. 2 is a flowchart of a control method for another electric vehicle according to a second embodiment of the present invention;
fig. 3 is a flowchart of another control method for an electric vehicle according to a third embodiment of the present invention;
fig. 4 is a specific flowchart of a control method for an electric vehicle according to a third embodiment of the present invention;
fig. 5 is a schematic structural diagram of a control device of an electric vehicle according to a fourth embodiment of the present invention.
Detailed Description
In order to make those skilled in the art better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that the terms "comprises" and "comprising," and any variations thereof, in the description and claims of the present invention and the above-described drawings, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.
Example one
Fig. 1 is a flowchart of a control method for an electric vehicle according to an embodiment of the present invention, where the present embodiment is applicable to a situation where a motor of the electric vehicle is not controlled, and only decelerates by stepping on a brake, and safety is low, and the method may be executed by a control device of the electric vehicle, and the device may be implemented in a software and/or hardware manner. The device can be configured in an electric vehicle, and with reference to fig. 1, the method specifically includes:
and S110, acquiring a required driving power parameter of the motor, a consumed power parameter of the vehicle-mounted electric appliance and a discharging power parameter of the power battery.
During the operation of the electric vehicle, the emergency cut-off of the power transmission of the motor can be controlled according to a diagnostic system, a Vehicle Control Unit (VCU), a Motor Controller (MCU), and a battery controller (BMS). The diagnosis system can acquire the required driving power parameter of the motor in the vehicle controller and the consumed power parameter of the vehicle-mounted electrical appliance, and can also acquire the discharging power parameter of the power battery by using the battery controller.
Specifically, the vehicle control unit may acquire a driving intention of the driver, and determine a required driving power parameter of the electric motor according to the driving intention. Specifically, the vehicle control unit judges the driving intention of the driver by acquiring the opening degree of the accelerator pedal, determines a required torque according to the opening degree of the accelerator pedal, namely, converts the opening degree of the accelerator pedal into the required torque of the driver, determines the required driving voltage and driving current if the motor outputs the corresponding torque according to the required torque, further determines the driving power, obtains a required driving power parameter, and then sends the required driving power parameter to the motor controller, and the motor controller controls the motor to output driving wheels through current and voltage, so that the electric vehicle is driven. If the required driving power parameter P is large, it means that the driver desires acceleration.
In addition, the vehicle control unit can also acquire the running state of the electric vehicle and determine the power consumption parameter of the vehicle-mounted electric appliance according to the running state. The running state of the electric vehicle can comprise gear information of the electric vehicle, the gear information comprises four gears of START, ON, ACC and LOCK, and under different gears, the states of electric appliances in the electric vehicle are different. Specifically, the START gear is a starting gear, when an ignition switch of the vehicle is arranged at the position, a starter circuit is connected to drive an engine to operate and START, for the electric vehicle, high voltage is electrified after ignition, and after the vehicle is started successfully, a key can automatically return to an ON gear; the LOCK gear is a locking gear, and the position is a position for inserting and pulling out a key, at the moment, except for an anti-theft system and a small lamp in the vehicle, a circuit is completely closed, and a steering wheel is locked; the ACC gear is an accessory switch-on gear, when the vehicle ignition switch is arranged at the position, an accessory (low-voltage) circuit is switched on, and equipment such as an in-vehicle illuminating lamp and a radio can be used; when the ON gear is a switch-ON gear and the ignition switch of the vehicle is placed at the position, the whole vehicle circuit is switched ON, and necessary preparation work and self-checking work are carried out ON the system for starting the engine.
When the vehicle control unit acquires that the running state of the electric vehicle is a starting gear, the vehicle control unit is connected with a vehicle circuit at the moment, but the starting state of each vehicle-mounted electrical appliance is still unknown, so that the vehicle control unit calculates the sum of the power of the vehicle-mounted electrical appliances in the starting state by acquiring the vehicle-mounted electrical appliances in the starting state in the electric vehicle, such as an air conditioner, a high-voltage to low-voltage device (DCDC) and the like, and obtains a power consumption parameter.
The battery controller is mainly used for intelligently managing and maintaining each battery unit, preventing the battery from being overcharged and overdischarged, prolonging the service life of the battery and monitoring the state of the battery. In the embodiment, the battery controller can calculate the battery power according to the running state of the electric vehicle, the voltage of the battery controller and the output current, so as to obtain the discharge power parameter of the power battery. Specifically, the battery controller obtains a discharge voltage and a discharge current of the power battery, determines a discharge power parameter according to the discharge voltage and the discharge current, and sends the discharge power parameter to the diagnostic system.
And S120, determining whether the electric vehicle is in a power output abnormal state or not according to the relation among the required driving power parameter, the consumed power parameter and the discharging power parameter.
After acquiring the required driving power parameter of the motor in the vehicle controller, the consumed power parameter of the vehicle-mounted electrical appliance and the discharge power parameter of the power battery in the battery controller, the diagnostic system judges the relationship among the required driving power parameter, the consumed power parameter and the discharge power parameter in real time to determine whether the electric vehicle is in a power output abnormal state. That is, the diagnostic system determines whether the discharge power parameter of the power battery exceeds the driver's demand (sum of the driving power parameter and the consumed power parameter) under the current vehicle electrical load, and it should be noted that the exceeded portion is caused by incorrect execution of the electric motor.
Specifically, the diagnosis system judges whether the difference between the sum of the required driving power parameter and the consumed power parameter and the discharge power parameter is greater than or equal to the safety limit value of abnormal power output in real time, if the difference between the sum of the required driving power parameter and the consumed power parameter and the discharge power parameter is greater than or equal to the safety limit value, the unexpected acceleration event is shown to occur at the moment, namely the motor is in failure, so that the motor is not controlled, and the electric vehicle is in an abnormal power output state; if the sum of the required driving power parameter and the consumed power parameter and the difference value of the discharge power parameter are smaller than the safety limit value, it is indicated that the acceleration of the motor is expected at the moment, namely the motor can normally run, the corresponding driving intention of a driver is executed, and the electric vehicle is not in a power output abnormal state and can normally run.
The safety limit for the abnormal power output indicates the tolerance of the driver to the unintended acceleration, and the lower the tolerance to the unintended acceleration, the smaller the safety limit is, so that the safety limit can be set according to the actual needs of different drivers. The power parameters transmitted between the systems inside the electric vehicle are not limited to the power signals, but may be voltages, currents, rotational speeds, torques, and the like used for calculating power.
And S130, if so, cutting off the electric connection between the power battery and the motor.
Specifically, the power battery is electrically connected with the motor through a high-voltage relay. If the electric vehicle is determined to be in a power output abnormal state after being judged by the diagnosis system, the diagnosis system sends an emergency power cut-off signal to the vehicle control unit, and the vehicle control unit sends a power output cut-off command to the battery controller after receiving the emergency power cut-off signal, so that the battery controller controls the high-voltage relay to be switched off, and the electric connection between the power battery and the motor is further cut off; and if the electric vehicle is determined not to be in the abnormal power output state after being judged by the diagnosis system, the diagnosis system continues to carry out real-time judgment.
According to the technical scheme of the embodiment, the required driving power parameter of the motor, the consumed power parameter of the vehicle-mounted electrical appliance and the discharging power parameter of the power battery are obtained; determining whether the electric vehicle is in a power output abnormal state or not according to the relation among the required driving power parameter, the consumed power parameter and the discharging power parameter; if so, the electric connection between the power battery and the motor is cut off, the problem that the electric vehicle in the prior art can only control the motor controller to output corresponding torque to wheels through the vehicle control unit is solved, but when the motor fails, the path fails, only the brake can be stepped on for speed reduction, and the safety requirement of the electric vehicle cannot be met, the power transmission can still be cut off when the motor fails to be controlled, namely, the power supply of the motor is cut off, so that the power output capability of the motor is lost, the damage caused by the unexpected acceleration of the electric vehicle is avoided, the driving safety is ensured, the physical structure of the electric vehicle is not changed, and further, the additional cost cannot be increased.
Example two
Fig. 2 is a flowchart of another control method for an electric vehicle according to a second embodiment of the present invention, and this embodiment preferably optimizes the determination of whether the electric vehicle is in the abnormal power output state according to the relationship among the required driving power parameter, the consumed power parameter and the discharging power parameter to obtain the power output abnormal state 1 -P 2 And if the power output is not less than the delta P and the first preset time continues, determining that the electric vehicle is in the abnormal power output state. And adding a characteristic to judge whether the high-voltage relay is normal; if yes, starting the electric vehicle, and acquiring a required driving power parameter of the motor, a consumed power parameter of the vehicle-mounted electric appliance and a discharge power parameter of the power battery. Referring to fig. 2, the method specifically includes:
s210, judging whether the high-voltage relay is normal, if so, starting the electric vehicle, and acquiring the required driving power parameter of the motor, the consumed power parameter of the vehicle-mounted electric appliance and the discharge power parameter of the power battery.
Specifically, the power battery is electrically connected with the motor through the high-voltage relay, the battery controller enables the power battery to break a high-voltage loop through the switching-off of the high-voltage relay, and the motor is not supplied with high-voltage power and cannot output driving power. Therefore, before acquiring the required driving power parameter of the motor, the consumed power parameter of the vehicle-mounted electrical appliance and the discharge power parameter of the power battery, the battery controller is required to monitor whether the high-voltage relay can normally act or not, if so, the electric vehicle is started, and the required driving power parameter of the motor, the consumed power parameter of the vehicle-mounted electrical appliance and the discharge power parameter of the power battery are acquired; if not normal, high-voltage relay has the trouble promptly, can not normally work, then forbid electric vehicle and start, avoid high-voltage relay trouble, if high-voltage relay adhesion, the electric connection between power battery and the motor that the condition that can not break off leads to can't cut off to driving safety has been guaranteed.
And S220, acquiring a required driving power parameter of the motor, a consumed power parameter of the vehicle-mounted electrical appliance and a discharging power parameter of the power battery.
S230, if | P + P 1 -P 2 If the power output is not less than the delta P and the first preset time is continued, determining that the electric vehicle is in a power output abnormal state; wherein P represents a required drive power parameter, P 1 Representing a power consumption parameter, P 2 Indicating a discharge power parameter and deltap indicating a safety limit for power output anomalies.
Specifically, the diagnostic system acquires a required driving power parameter P of a motor and a consumed power parameter P of a vehicle-mounted electric appliance in the vehicle control unit 1 And discharge power parameter P of power battery in battery controller 2 Then, real-time judging the required driving power parameter P and the consumed power parameter P 1 Sum of, and discharge power parameter P 2 Whether the absolute value of the difference is larger than or equal to a safety limit value delta P of abnormal power output or not, if the driving power parameter P and the consumed power parameter P are required 1 Sum of, and discharge power parameter P 2 The absolute value of the difference is greater than or equal to the safety limit value delta P of the abnormal power output, and the first preset time is continued, so that the unexpected acceleration event is shown, namely the motor is failed, the control is not carried out, and the electric vehicle is in the abnormal power output state; if the driving power parameter P and the consumed power parameter P are required 1 Sum of, and discharge power parameter P 2 The absolute value of the difference is smaller than the safety limit value delta P of abnormal power output, which indicates that the acceleration of the motor is in expectation, the motor can normally run, corresponding driving intention of a driver is executed, the electric vehicle is not in an abnormal power output state, or the driving power parameter P and the consumed power are requiredParameter P 1 Sum of, and discharge power parameter P 2 The absolute value of the difference is larger than or equal to the safety limit value delta P of abnormal power output, but the difference does not continue for the first preset time, which indicates that the acceleration is instantaneous acceleration, and the motor can still normally run, so that the electric vehicle is not in the abnormal power output state and can normally run. The first preset time can be set as required, and the first preset time is set to be 200ms in the implementation.
And S240, if so, cutting off the electric connection between the power battery and the motor.
According to the technical scheme of the embodiment, whether the high-voltage relay is normal or not is judged before the vehicle is started, if yes, the electric vehicle is started, the required driving power parameter of the motor, the consumed power parameter of the vehicle-mounted electrical appliance and the discharging power parameter of the power battery are obtained, if not, the electric vehicle is prohibited from being started, and therefore the situation that the electric connection between the power battery and the motor cannot be cut off due to the fault of the high-voltage relay is avoided, and the situation that the electric connection between the power battery and the motor cannot be cut off due to the fact that the high-voltage relay is in fault is solved through the absolute value of P + P 1 -P 2 The method comprises the steps of determining that the electric vehicle is in a power output abnormal state if | > delta P and the first preset time is continued, avoiding the influence of instantaneous acceleration on judgment, improving the accuracy of a judgment result, solving the problem that the electric vehicle in the prior art can only control a motor controller to output corresponding torque to wheels through a vehicle controller, and when a motor fails, the path fails, only can brake and decelerate, and cannot meet the safety requirement of the electric vehicle, and realizing that power transmission can still be cut off, namely power supply of the motor is cut off when the motor fails to be controlled, so that the motor loses power output capacity, avoiding the damage caused by unexpected acceleration of the electric vehicle, ensuring driving safety, and not changing the physical structure of the electric vehicle, and further not increasing additional cost.
EXAMPLE III
Fig. 3 is a flowchart of another control method for an electric vehicle according to a third embodiment of the present invention, and fig. 4 is a specific flowchart of the control method for an electric vehicle according to the third embodiment of the present invention, and this embodiment preferably adds a feature "to control the electric motor to reduce the output torque based on the above embodiments; and if the output torque of the motor is greater than a preset threshold value after the second preset time, cutting off the electric connection between the power battery and the motor. Referring to fig. 3 and 4, the method specifically includes:
and S310, judging whether the high-voltage relay is normal, if so, starting the electric vehicle, and acquiring a required driving power parameter of the motor, a consumed power parameter of the vehicle-mounted electric appliance and a discharge power parameter of the power battery.
And S320, acquiring a required driving power parameter of the motor, a consumed power parameter of the vehicle-mounted electrical appliance and a discharging power parameter of the power battery.
S330, if | P + P 1 -P 2 And if the power output is not less than the delta P and the first preset time is continued, determining that the electric vehicle is in the abnormal power output state.
And S340, if so, controlling the motor to reduce the output torque, and if the output torque of the motor is greater than a preset threshold value after a second preset time, cutting off the electric connection between the power battery and the motor.
If the electric vehicle is determined to be in the abnormal power output state after being judged by the diagnosis system, the diagnosis system sends an emergency power cut-off signal to the vehicle control unit, and the vehicle control unit firstly confirms whether the motor has a fault or not after receiving the emergency power cut-off signal. Specifically, the vehicle control unit sends a torque reduction request to the motor controller, and the motor controller controls the motor to reduce the output torque and judges whether the output torque of the motor is greater than a preset threshold value after a second preset time. If the output torque of the motor is still larger than the preset threshold value after the second preset time, which indicates that the motor has a fault, the vehicle control unit sends a power output cutting instruction to the battery controller, so that the battery controller controls the high-voltage relay to be switched off, and the electric connection between the power battery and the motor is cut off; and if the output torque of the motor is smaller than the preset threshold value after the second preset time, which indicates that the motor can still be effectively controlled, the electric vehicle normally runs. The second preset time may be set as needed, and in this embodiment, the second preset time is preferably 500 ms.
And if the electric vehicle is determined not to be in the abnormal power output state after being judged by the diagnosis system, the diagnosis system continues to carry out real-time judgment.
According to the technical scheme, after the electric vehicle is judged to be in the power output abnormal state through the diagnosis system, whether the motor has a fault is firstly confirmed without directly cutting off the electric connection between the power battery and the motor, the system of the electric vehicle can be protected, and whether the motor has the fault is further judged, so that the accuracy of the judgment result can be improved, the condition that the electric vehicle cannot normally run due to misjudgment is avoided, the power transmission can still be cut off when the motor fault is not controlled, namely, the power supply of the motor is cut off, the power output capacity of the motor is lost, the damage caused by the unexpected acceleration of the electric vehicle is avoided, the driving safety is ensured, the physical structure of the electric vehicle is not changed, and the additional cost is not increased.
Example four
Fig. 5 is a schematic structural diagram of a control device of an electric vehicle according to a fourth embodiment of the present invention, where this embodiment is applicable to a situation where a motor of an electric vehicle is not controlled in fault, and only decelerates by stepping on a brake, and safety is low, and the control device of the electric vehicle has a specific structure as follows:
the obtaining module 50 is configured to obtain a required driving power parameter of the motor, a consumed power parameter of the vehicle-mounted electrical appliance, and a discharge power parameter of the power battery.
The judging module 51 is configured to determine whether the electric vehicle is in a power output abnormal state according to a relationship between the required driving power parameter, the consumed power parameter, and the discharging power parameter.
And a control module 52 for cutting off the electrical connection between the power battery and the motor when it is determined that the electric vehicle is in the power output abnormal state.
The obtaining module 50 is specifically configured to obtain a driving intention of a driver, determine a required driving power parameter of the motor according to the driving intention, obtain an operating state of the electric vehicle, and determine a power consumption parameter of the vehicle-mounted electrical appliance and a discharge power parameter of the power battery according to the operating state.
Specifically, the obtaining module 50 includes a demand driving power parameter determining submodule, a consumption power parameter determining submodule, and a discharge power parameter determining submodule.
The required driving power parameter determining submodule is used for acquiring the opening degree of an accelerator pedal, determining required torque according to the opening degree of the accelerator pedal, determining driving voltage and driving current according to the required torque, and determining required driving power parameters according to the driving voltage and the driving current.
And the power consumption parameter determining submodule is used for acquiring the vehicle-mounted electrical appliances in the opening state in the electric vehicle, and calculating the sum of the power of the vehicle-mounted electrical appliances in the opening state to obtain the power consumption parameter.
And the discharge power parameter determination submodule is used for acquiring the discharge voltage and the discharge current of the power battery and determining the discharge power parameter according to the discharge voltage and the discharge current.
The judging module 51 is further configured to determine if | P + P 1 -P 2 If the power output is not less than the first preset time, determining that the electric vehicle is in a power output abnormal state, wherein P represents the required driving power parameter, and P continues for the first preset time 1 Representing said power consumption parameter, P 2 And the parameter represents the discharge power, and the delta P represents a safety limit value of power output abnormity.
The control module 52 is further configured to control the motor to decrease the output torque when it is determined that the electric vehicle is in the abnormal power output state, and disconnect the electrical connection between the power battery and the motor if the output torque of the motor is greater than the preset threshold after the second preset time.
The control device of the electric vehicle further comprises a monitoring module 53, which is used for judging whether the high-voltage relay is normal or not, if so, starting the electric vehicle, acquiring a required driving power parameter of the motor, a consumed power parameter of the vehicle-mounted electrical appliance and a discharge power parameter of the power battery, and if not, prohibiting the electric vehicle from being started.
According to the technical scheme of the embodiment, the required driving power parameter of the motor, the consumed power parameter of the vehicle-mounted electrical appliance and the discharging power parameter of the power battery are obtained; determining whether the electric vehicle is in a power output abnormal state or not according to the relation among the required driving power parameter, the consumed power parameter and the discharging power parameter; if so, the electric connection between the power battery and the motor is cut off, the problem that the electric vehicle in the prior art can only control the motor controller to output corresponding torque to wheels through the vehicle control unit, but when the motor fails, the path fails, only the brake can be stepped on for speed reduction, and the safety requirement of the electric vehicle cannot be met is solved, the power transmission can still be cut off when the motor fails to be controlled, namely, the power supply of the motor is cut off, so that the motor loses the power output capability, the damage caused by the unexpected acceleration of the electric vehicle is avoided, the driving safety is ensured, the physical structure of the electric vehicle is not changed, and further, the additional cost cannot be increased.
EXAMPLE five
The electric vehicle provided by the embodiment of the invention comprises the control device of the electric vehicle provided by the embodiment of the invention, and has corresponding functional modules and beneficial effects of the execution method.
It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will appreciate that the present invention is not limited to the particular embodiments described herein, and that various obvious changes, rearrangements and substitutions will now be apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in some detail by the above embodiments, the invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the invention, and the scope of the invention is determined by the scope of the appended claims.

Claims (11)

1. A control method of an electric vehicle, characterized by comprising:
acquiring a required driving power parameter of a motor, a consumed power parameter of a vehicle-mounted electrical appliance and a discharge power parameter of a power battery;
determining whether the electric vehicle is in a power output abnormal state or not according to the relation among the required driving power parameter, the consumed power parameter and the discharging power parameter;
if yes, the electric connection between the power battery and the motor is cut off.
2. The control method according to claim 1, wherein obtaining the required driving power parameter of the motor, the consumed power parameter of the vehicle-mounted electrical appliance and the discharging power parameter of the power battery comprises:
acquiring a driving intention of a driver, and determining a required driving power parameter of a motor according to the driving intention;
and acquiring the running state of the electric vehicle, and determining the consumed power parameter of the vehicle-mounted electric appliance and the discharge power parameter of the power battery according to the running state.
3. The control method according to claim 2, wherein acquiring a driving intention of a driver, and determining a required driving power parameter of the motor based on the driving intention, includes:
acquiring the opening degree of an accelerator pedal;
determining a required torque according to the opening degree of the accelerator pedal;
determining a driving voltage and a driving current according to the required torque;
and determining the required driving power parameter according to the driving voltage and the driving current.
4. The control method according to claim 2, wherein the step of obtaining the operating state of the electric vehicle and determining the consumed power parameter of the vehicle-mounted electric appliance and the discharge power parameter of the power battery according to the operating state comprises the following steps:
acquiring a vehicle-mounted electric appliance in an opening state in the electric vehicle;
calculating the sum of the powers of the vehicle-mounted electrical appliances in the opening state to obtain the consumed power parameter;
acquiring discharge voltage and discharge current of a power battery;
and determining the discharge power parameter according to the discharge voltage and the discharge current.
5. The control method according to claim 1, wherein determining whether the electric vehicle is in a power output abnormal state according to the relationship of the required driving power parameter, the consumed power parameter, and the discharge power parameter includes:
if | P + P 1 -P 2 If the power output is not less than the delta P and the first preset time is continued, determining that the electric vehicle is in a power output abnormal state;
wherein P represents the required drive power parameter, P 1 Representing said power consumption parameter, P 2 And the parameter represents the discharge power, and the delta P represents a safety limit value of power output abnormity.
6. The control method according to claim 1, further comprising, before cutting off the electrical connection between the power battery and the electric motor:
and controlling the motor to reduce the output torque.
7. The control method according to claim 6, further comprising, after controlling the motor to reduce the output torque:
and if the output torque of the motor is greater than a preset threshold value after the second preset time, cutting off the electric connection between the power battery and the motor.
8. The control method according to claim 1, wherein the power battery is electrically connected to the motor through a high-voltage relay, and the disconnecting the power battery from the motor comprises:
and controlling the high-voltage relay to be switched off.
9. The control method according to claim 1, wherein the power battery is electrically connected with the motor through a high-voltage relay, and before acquiring the required driving power parameter of the motor, the consumed power parameter of the vehicle-mounted electrical appliance and the discharging power parameter of the power battery, the method further comprises the following steps:
judging whether the high-voltage relay is normal or not;
if so, starting the electric vehicle, and acquiring a required driving power parameter of the motor, a consumed power parameter of the vehicle-mounted electric appliance and a discharge power parameter of the power battery;
and if not, prohibiting the electric vehicle from starting.
10. A control device of an electric vehicle, characterized by comprising:
the acquisition module is used for acquiring required driving power parameters of the motor, consumed power parameters of the vehicle-mounted electrical appliance and discharge power parameters of the power battery;
the judging module is used for determining whether the electric vehicle is in a power output abnormal state or not according to the relation among the required driving power parameter, the consumed power parameter and the discharging power parameter;
and the control module is used for cutting off the electric connection between the power battery and the motor when the electric vehicle is determined to be in the abnormal power output state.
11. An electric vehicle characterized by comprising the control device of claim 10.
CN202210446503.6A 2022-04-26 2022-04-26 Control method and device of electric vehicle and electric vehicle Pending CN114789660A (en)

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Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103052530A (en) * 2010-08-02 2013-04-17 株式会社V-Ens Electric vehicle and method for controlling same
US20130127400A1 (en) * 2010-08-02 2013-05-23 V-Ens Co., Ltd. Electric vehicle and charging control method for auxiliary battery thereof
CN104608763A (en) * 2013-11-01 2015-05-13 北汽福田汽车股份有限公司 Car torque safety monitoring method and system
US20170036672A1 (en) * 2015-08-07 2017-02-09 Toyota Jidosha Kabushiki Kaisha Driving device for vehicle
CN107128187A (en) * 2017-04-12 2017-09-05 宁德时代新能源科技股份有限公司 Power supply system, electric drive device, pure electric vehicle and working method thereof
CN110641283A (en) * 2018-06-11 2020-01-03 三菱电机株式会社 Power control device
CN111452670A (en) * 2019-01-18 2020-07-28 通用汽车环球科技运作有限责任公司 Battery pack voltage switching system and control logic for multi-battery pack electrically driven vehicle
CN113352894A (en) * 2021-04-28 2021-09-07 东风汽车集团股份有限公司 Power battery high-voltage abnormal power-off protection method and system
US20210354586A1 (en) * 2019-02-08 2021-11-18 Denso Corporation Driving control device and driving system for vehicle

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103052530A (en) * 2010-08-02 2013-04-17 株式会社V-Ens Electric vehicle and method for controlling same
US20130127400A1 (en) * 2010-08-02 2013-05-23 V-Ens Co., Ltd. Electric vehicle and charging control method for auxiliary battery thereof
CN104608763A (en) * 2013-11-01 2015-05-13 北汽福田汽车股份有限公司 Car torque safety monitoring method and system
US20170036672A1 (en) * 2015-08-07 2017-02-09 Toyota Jidosha Kabushiki Kaisha Driving device for vehicle
CN107128187A (en) * 2017-04-12 2017-09-05 宁德时代新能源科技股份有限公司 Power supply system, electric drive device, pure electric vehicle and working method thereof
CN110641283A (en) * 2018-06-11 2020-01-03 三菱电机株式会社 Power control device
CN111452670A (en) * 2019-01-18 2020-07-28 通用汽车环球科技运作有限责任公司 Battery pack voltage switching system and control logic for multi-battery pack electrically driven vehicle
US20210354586A1 (en) * 2019-02-08 2021-11-18 Denso Corporation Driving control device and driving system for vehicle
CN113352894A (en) * 2021-04-28 2021-09-07 东风汽车集团股份有限公司 Power battery high-voltage abnormal power-off protection method and system

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