CN111152661A - Failure control method for electric drive system of four-wheel distributed drive passenger car - Google Patents

Failure control method for electric drive system of four-wheel distributed drive passenger car Download PDF

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Publication number
CN111152661A
CN111152661A CN202010070125.7A CN202010070125A CN111152661A CN 111152661 A CN111152661 A CN 111152661A CN 202010070125 A CN202010070125 A CN 202010070125A CN 111152661 A CN111152661 A CN 111152661A
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wheel
vehicle
failure
motor
mode
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Inventor
陈超
苏亮
朱武喜
刘志伟
宋光吉
黄玲
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Xiamen King Long United Automotive Industry Co Ltd
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Xiamen King Long United Automotive Industry 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
    • 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
    • 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
    • B60L15/00—Methods, circuits, or devices for controlling the traction-motor speed of electrically-propelled vehicles
    • B60L15/32—Control or regulation of multiple-unit electrically-propelled vehicles
    • 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
    • B60L2220/00—Electrical machine types; Structures or applications thereof
    • B60L2220/40—Electrical machine applications
    • B60L2220/42—Electrical machine applications with use of more than one motor
    • 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
    • B60L2220/00—Electrical machine types; Structures or applications thereof
    • B60L2220/40—Electrical machine applications
    • B60L2220/44—Wheel Hub motors, i.e. integrated in the wheel hub
    • 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
    • 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

Abstract

The invention discloses a failure control method for an electric drive system of a four-wheel distributed drive passenger car, which comprises the following steps: selecting the vehicle to enter a two-drive mode or a parking mode according to a failure mode of the electric drive system; and when the two-wheel drive mode is entered, motor torque distribution is carried out on the motor which is not failed: calculating the ideal yaw rate under different conditions based on the reference ideal understeer degree US
Figure RE-956306DEST_PATH_IMAGE001
(ii) a Calculating the ideal centroid slip angle by combining an integral estimation algorithm and an empirical formula of the centroid slip angle upper limit value
Figure RE-309927DEST_PATH_IMAGE002
(ii) a Using fuzzy control algorithm, the yaw angle is adjustedSpeed of rotation
Figure RE-842539DEST_PATH_IMAGE003
And centroid slip angle
Figure RE-182385DEST_PATH_IMAGE004
As an input variable, calculating an additional yaw moment
Figure RE-116843DEST_PATH_IMAGE005
(ii) a Obtaining an output torque MAP of the vehicle under different accelerator and vehicle speeds through off-line calculation, and obtaining expected longitudinal driving torque through interpolation of the opening of an accelerator pedal and the current vehicle speed according to the operation intention of a driver
Figure RE-375786DEST_PATH_IMAGE006
(ii) a Based on a double-track two-degree-of-freedom nonlinear vehicle model and combined with an additional yaw moment
Figure RE-395695DEST_PATH_IMAGE005
And desired longitudinal drive torque
Figure RE-273652DEST_PATH_IMAGE007
And distributing motor torque to the motor which is not failed.

Description

Failure control method for electric drive system of four-wheel distributed drive passenger car
Technical Field
The invention relates to the technical field of vehicle control, in particular to a failure control method for an electric drive system of a four-wheel distributed drive passenger car.
Background
The electric drive system of the four-wheel distributed drive passenger car comprises four wheel motors and related components, and compared with a traditional centralized control mode, a distributed control mode of wheels is easier to exert the dynamic property of the car and ensure the stability of the car, and meanwhile, the drive working condition of the car is more complex, and higher fault tolerance is required. At present, a processing method of deceleration and stopping is generally adopted for failure control of an electric drive system, and driving can be continued only after vehicle failure maintenance processing. The processing method obviously does not fully exert the independent driving advantages of the four-wheel distributed drive vehicle, and has a plurality of disadvantages. Therefore, how to optimize the failure control strategy of the electric drive system so as to exert the advantage of independent controllability of the distributed wheel-side motor to the greatest extent on the premise of ensuring the safety of the vehicle is a problem which needs to be solved urgently at the present stage.
Disclosure of Invention
The invention provides a failure control method for an electric drive system of a four-wheel distributed drive passenger car, and mainly aims to solve the problems in the prior art.
In order to solve the technical problems, the invention adopts the following technical scheme:
a failure control method for an electric drive system of a four-wheel distributed drive passenger car comprises the following steps:
(1) selecting the vehicle to enter a two-drive mode or a parking mode according to a failure mode of the electric drive system;
(2) and when the two-wheel drive mode is entered, motor torque distribution is carried out on the motor which is not failed:
(2.1) calculating different front wheel turning angles according to the reference ideal understeer degree US
Figure RE-4551DEST_PATH_IMAGE001
Vehicle speed
Figure RE-799332DEST_PATH_IMAGE002
Coefficient of adhesion to road surface
Figure RE-228039DEST_PATH_IMAGE003
Ideal yaw rate
Figure RE-614021DEST_PATH_IMAGE004
；
(2.2) calculating the ideal centroid slip angle by combining an integral estimation algorithm and an empirical formula of the centroid slip angle upper limit value
Figure RE-377446DEST_PATH_IMAGE005
；
(2.3) adopting a fuzzy control algorithm to calculate the yaw rate
Figure RE-241497DEST_PATH_IMAGE006
And centroid slip angle
Figure RE-790290DEST_PATH_IMAGE007
Error of (2)
Figure RE-347174DEST_PATH_IMAGE008
Calculating an additional yaw moment as an input variable
Figure RE-348628DEST_PATH_IMAGE009
；
(2.4) obtaining an output torque MAP (MAP) of the vehicle under different accelerator and vehicle speeds through off-line calculation, and obtaining expected longitudinal driving torque through interpolation of the opening of an accelerator pedal and the current vehicle speed according to the operation intention of a driver
Figure RE-16369DEST_PATH_IMAGE010
；
(2.5) combining additional yaw moment based on double-track two-degree-of-freedom nonlinear vehicle model
Figure RE-403357DEST_PATH_IMAGE011
And desired longitudinal drive torque
Figure RE-865563DEST_PATH_IMAGE012
And distributing motor torque to the motor which is not failed.
Further, in the step (1), the failure modes include a single-wheel motor failure mode, a same-side double-wheel motor failure mode, a different-side double-wheel motor failure mode and a multi-wheel motor failure mode; when the vehicle is in a single-wheel motor failure mode or a double-wheel motor failure mode on different sides, the vehicle enters a two-wheel drive mode; and when the vehicle is in the same-side failure of the double-wheel motor or the multi-wheel motor, the vehicle enters a parking mode.
Further, when the vehicle enters a parking mode, under the straight-ahead running condition, a control method of setting the output torque of the motor which is not failed to be zero is adopted to realize deceleration parking; under the turning condition, a control method of applying braking torque to the outer wheels or applying driving torque to the inner wheels to improve the oversteering tendency is adopted to realize deceleration and stop.
Further, in the step (2.1), the ideal understeer degree is:
Figure RE-823154DEST_PATH_IMAGE013
。
further, in the step (2.2), an empirical formula of the upper limit value of the centroid slip angle is as follows:
Figure RE-281205DEST_PATH_IMAGE014
。
further, in the step (2.3), the yaw rate error
Figure RE-539011DEST_PATH_IMAGE015
Centroid slip angle error
Figure RE-703276DEST_PATH_IMAGE016
And additional yaw moment
Figure RE-679322DEST_PATH_IMAGE017
All adopt a triangular membership function, and adopt a fuzzy solving mode of an area gravity center method to convert the output fuzzy quantity into accurate control quantity so as to obtain an additional yaw moment
Figure RE-688867DEST_PATH_IMAGE018
。
Further, in the step (2.5), the dynamic equation of the vehicle model is:
Figure RE-66758DEST_PATH_IMAGE019
。
go toStep (2.5), firstly, according to the road surface adhesion coefficient
Figure RE-870766DEST_PATH_IMAGE020
Maximum yaw moment provided by lower road surface
Figure RE-583376DEST_PATH_IMAGE021
For calculated additional yaw moment
Figure RE-131032DEST_PATH_IMAGE022
Making a correction, said maximum yaw moment
Figure RE-363430DEST_PATH_IMAGE023
Comprises the following steps:
Figure RE-603919DEST_PATH_IMAGE024
in the formula:
Figure RE-23399DEST_PATH_IMAGE025
vertical loads of the left front wheel, the right front wheel, the left rear wheel and the right rear wheel respectively;
Figure RE-889593DEST_PATH_IMAGE026
the distance between the wheels of the front axle is,
Figure RE-710918DEST_PATH_IMAGE027
is the rear axle wheel base;
actual additional yaw moment
Figure RE-387887DEST_PATH_IMAGE028
Comprises the following steps:
Figure RE-560242DEST_PATH_IMAGE029
。
from the above description of the structure of the present invention, compared with the prior art, the present invention has the following advantages:
1. according to the invention, two counter measures are designed according to the failure state of the electric drive system, when the failure mode is a vehicle single-wheel motor failure mode or an opposite-side double-wheel motor failure mode, a vehicle speed keeping type control method in a two-drive mode can be adopted, and after the expected yaw moment is calculated, torque distribution is carried out on the motor which is not failed by combining with the intention parameters of a driver, so that the vehicle can maximally utilize the independently controllable advantages of the wheel-side motor on the premise of ensuring the safety, the residual power performance is fully exerted, and the driving capability and the operation stability of the vehicle are kept.
2. When the failure mode is that the double-wheel motor on the same side fails or the multi-wheel motor fails, a deceleration parking type failure control method of the parking mode can be adopted, a control method of setting the torque of the motor which does not fail to zero is adopted under the direct driving working condition, and a rule-based control method is adopted under the turning working condition, and the tendency of oversteering of the vehicle is improved by applying driving torque to the inner wheels or applying braking torque to the outer wheels.
Drawings
FIG. 1 is a schematic diagram of the classification of failure modes of the electric drive system of the present invention.
FIG. 2 is a schematic diagram of a control algorithm for the two-drive mode of the present invention.
Fig. 3 is a schematic diagram of a fuzzy control rule.
Fig. 4 is a schematic diagram of a control algorithm of the parking mode in the invention.
Detailed Description
The following describes embodiments of the present invention with reference to the drawings.
As shown in fig. 1, according to the number and distribution of the fault wheel-side motors, the failure modes of the electric drive system are specifically divided into a single-wheel motor failure mode, a double-wheel motor failure mode and a multi-wheel motor failure mode, wherein the double-wheel motor failure mode is divided into a double-wheel motor failure mode on the same side and a double-wheel motor failure mode on the different side. Specifically, the single-wheel motor failure mode comprises four conditions of failure of a left front wheel motor, failure of a left rear wheel motor, failure of a right front wheel motor and failure of a right rear wheel motor; the same-side double-wheel motor failure mode comprises two conditions of failure of a left double-wheel motor and failure of a right double-wheel motor; the different-side double-wheel motor failure mode comprises four conditions of failure of a front two-wheel motor, failure of a rear two-wheel motor, failure of a left front wheel right rear wheel motor and failure of a right front wheel left rear wheel motor; the failure modes of the multi-wheel motor comprise five conditions of failure of a left wheel motor of the front two wheels and a rear wheel motor of the rear two wheels, failure of a right wheel motor of the front two wheels, failure of a left wheel motor of the rear two wheels, failure of a right wheel motor of the rear two wheels and failure of all four wheel motors.
As shown in fig. 1, since the distributed wheel-side motors have the advantage of being independently controllable, when a motor failure occurs, the motor failure can be analyzed according to the steering characteristics of the vehicle in each failure mode, so that a countermeasure of a two-wheel drive mode or a parking mode can be taken.
As shown in fig. 1, specifically, the two-drive mode is to use the non-failed motor to provide the driving torque required during normal running, and to control the torque distribution between the non-failed motors by a direct yaw moment so as to maintain the driving capability and the driving stability of the vehicle, for example: when the single-wheel motor fails, the remaining three motors can work normally, so that the torque of the motor on the opposite side of the failed motor can be set to zero, the two-wheel drive mode in a front-wheel drive or rear-wheel drive mode is converted, and the vehicle body is kept stable and continues to run by distributing the torque among the motors which do not fail again; when the double-wheel motor on the different side fails, the stress conditions on the left side and the right side of the vehicle body can reach a balanced state by adjusting the driving torque of the motor which does not fail, so that the vehicle body is kept stable and continues to run, and therefore a two-drive mode can be adopted.
Specifically, as shown in fig. 1, the parking mode is to adopt deceleration parking type failure control, that is, to rapidly reduce the vehicle speed, reduce the motion parameters such as yaw angular velocity and lateral acceleration, and to improve the vehicle body stable state during parking as a control target. For example, when the double-wheel motor on the same side fails, if the double-wheel motor on the other side is used for driving, the left and right stress of the vehicle is unbalanced, the vehicle is unstable, and traffic accidents are easily caused, so that the vehicle is rapidly decelerated and stopped; when the multi-wheel motor fails, if the multi-wheel motor is driven by the motor which does not fail, the stress on the vehicle body is unbalanced, the vehicle body is unstable, and therefore the vehicle is decelerated and stopped rapidly.
The following detailed analysis is performed on the vehicle speed holding type failure control algorithm of the two-drive mode:
1. calculating different front wheel turning angles according to the reference ideal understeer degree US
Figure RE-715280DEST_PATH_IMAGE030
Vehicle speed
Figure RE-922271DEST_PATH_IMAGE031
Coefficient of adhesion to road surface
Figure RE-770141DEST_PATH_IMAGE032
Ideal yaw rate
Figure RE-679060DEST_PATH_IMAGE033
：
According to the ideal understeer of the vehicle:
Figure RE-372210DEST_PATH_IMAGE034
in the formula:
Figure RE-168127DEST_PATH_IMAGE035
is the front axle equivalent slip angle;
Figure RE-186899DEST_PATH_IMAGE036
is the rear axle equivalent slip angle;
Figure RE-68267DEST_PATH_IMAGE037
is the vehicle lateral acceleration and C is a control parameter.
The equivalent slip angles of the front shaft and the rear shaft are as follows:
Figure RE-830687DEST_PATH_IMAGE038
in the formula:
Figure RE-733308DEST_PATH_IMAGE039
is the centroid slip angle;
Figure RE-657402DEST_PATH_IMAGE040
the distances from the front axle and the rear axle to the center of mass respectively;
Figure RE-291646DEST_PATH_IMAGE041
the yaw angular velocity;
Figure RE-592177DEST_PATH_IMAGE042
is the vehicle longitudinal speed;
Figure RE-628266DEST_PATH_IMAGE043
is the corner of the front wheel.
The conjunctive types (1.1), (1.2) and (1.3) can result in the understeer expression:
Figure RE-723261DEST_PATH_IMAGE044
the turning angles of the front wheels at different positions can be calculated
Figure RE-844801DEST_PATH_IMAGE045
And vehicle speed
Figure RE-932711DEST_PATH_IMAGE046
The following reference lateral accelerations are:
Figure RE-823307DEST_PATH_IMAGE047
adhesion coefficient limit according to current driving road surface
Figure RE-89203DEST_PATH_IMAGE048
Obtaining the ideal yaw rate under the current road surface condition
Figure RE-432460DEST_PATH_IMAGE049
Comprises the following steps:
Figure RE-340373DEST_PATH_IMAGE050
2. combined integral estimation methodCalculating the ideal centroid slip angle by an empirical formula of the upper limit value of the centroid slip angle
Figure RE-85475DEST_PATH_IMAGE051
：
Calculating a reference centroid slip angle using integral estimation
Figure RE-787852DEST_PATH_IMAGE052
Comprises the following steps:
Figure RE-602093DEST_PATH_IMAGE053
the upper limit value of the centroid slip angle takes an empirical formula as follows:
Figure RE-48118DEST_PATH_IMAGE054
when the actual mass center slip angle of the vehicle
Figure RE-647726DEST_PATH_IMAGE055
Less than or equal to the threshold value
Figure RE-521005DEST_PATH_IMAGE056
Then, the ideal barycenter slip angle selects the reference value of the integral estimation result
Figure RE-838853DEST_PATH_IMAGE057
(ii) a When the actual centroid slip angle is larger than
Figure RE-822990DEST_PATH_IMAGE058
When the vehicle is in a destabilization state or is about to be destabilized, the ideal centroid slip angle is selected to be 0; when the centroid slip angle is at
Figure RE-542684DEST_PATH_IMAGE056
And
Figure RE-570552DEST_PATH_IMAGE058
and (3) selecting according to a linear relation. I.e. ideal centroid slip angle
Figure RE-375697DEST_PATH_IMAGE059
The values are as follows:
Figure RE-163524DEST_PATH_IMAGE060
3. using fuzzy control algorithm to measure yaw rate
Figure RE-737725DEST_PATH_IMAGE061
And centroid slip angle
Figure RE-952806DEST_PATH_IMAGE062
Error of (2)
Figure RE-979668DEST_PATH_IMAGE063
Calculating an additional yaw moment as an input variable
Figure RE-571186DEST_PATH_IMAGE064
；
Considering the difference of the running environmental conditions, road conditions and the performance of the whole vehicle in the running process of the whole vehicle, the traditional control model is difficult to obtain good control effect, so that in order to improve the control precision and the robustness to external disturbance, the fuzzy control algorithm is adopted to calculate the additional yaw moment
Figure RE-986511DEST_PATH_IMAGE064
。
(1) A fuzzy control algorithm: error of yaw angular velocity and centroid slip angle
Figure RE-372493DEST_PATH_IMAGE065
Adding yaw moment as input
Figure RE-152231DEST_PATH_IMAGE066
As an output. Yaw rate error
Figure RE-281861DEST_PATH_IMAGE067
Side of center of massDeviation angle error
Figure RE-299495DEST_PATH_IMAGE068
And additional yaw moment
Figure RE-121958DEST_PATH_IMAGE069
All adopt triangular membership functions. The yaw rate error and the centroid yaw angle error are divided into 7 fuzzy subsets, NB (negative large), NM (negative medium), NS (negative small), ZE (zero), PS (positive small), PM (positive medium), and PB (positive large), respectively. Meanwhile, in order to improve the control accuracy, the output additional yaw moment is divided into 9 fuzzy subsets, namely NVB (negative large), NB (negative large), NM (negative medium), NS (negative small), ZE (zero), PS (positive small), PM (positive medium), PB (positive large) and PVB (positive large).
(2) Fuzzy control rule:
when understeer steering
Figure RE-372679DEST_PATH_IMAGE070
The method comprises the following steps: an additional yaw moment in the positive direction is applied to reduce the understeer tendency, depending on the yaw-rate error
Figure RE-306000DEST_PATH_IMAGE071
And centroid slip angle error
Figure RE-443721DEST_PATH_IMAGE072
Determining the magnitude of the additional yaw moment; when absolute value of yaw rate error
Figure RE-171505DEST_PATH_IMAGE073
When the magnitude is larger, a larger positive additional yaw moment is output
Figure RE-660255DEST_PATH_IMAGE074
When the absolute value of the yaw rate error
Figure RE-131688DEST_PATH_IMAGE075
Smaller, forward attachmentYaw moment
Figure RE-389494DEST_PATH_IMAGE076
Absolute value of deviation angle error with centroid
Figure RE-803027DEST_PATH_IMAGE077
Is increased.
When oversteering
Figure RE-513494DEST_PATH_IMAGE078
The method comprises the following steps: an additional yaw moment in the opposite direction is applied to reduce the oversteering tendency, depending on the yaw-rate error
Figure RE-788617DEST_PATH_IMAGE079
And centroid slip angle error
Figure RE-166509DEST_PATH_IMAGE080
Determines the magnitude of the additional yaw moment. When absolute value of yaw rate error
Figure RE-236096DEST_PATH_IMAGE081
When the absolute value of the output is larger, the reverse additional yaw moment with larger absolute value is output
Figure RE-433859DEST_PATH_IMAGE082
When the absolute value of the yaw rate error
Figure RE-247094DEST_PATH_IMAGE083
Small, reverse additional yaw moment
Figure RE-728760DEST_PATH_IMAGE082
Absolute value of (1) with the absolute value of the centroid slip angle error
Figure RE-969249DEST_PATH_IMAGE084
Is reduced.
(3) And (3) deblurring: the area gravity center method is adopted to convert the output fuzzy quantity into accurate control quantity to obtain additional yaw moment
Figure RE-919887DEST_PATH_IMAGE082
。
3. Obtaining an output torque MAP of the vehicle under different accelerator and vehicle speeds through off-line calculation, and obtaining expected longitudinal driving torque through interpolation of the opening of an accelerator pedal and the current vehicle speed according to the operation intention of a driver
Figure RE-271234DEST_PATH_IMAGE085
；
4. Based on a double-track two-degree-of-freedom nonlinear vehicle model and combined with an additional yaw moment
Figure RE-358139DEST_PATH_IMAGE082
And desired longitudinal drive torque
Figure RE-35108DEST_PATH_IMAGE085
Motor torque distribution is carried out on the motor which is not failed:
simplifying a double-track two-degree-of-freedom vehicle dynamic model, considering that inner and outer wheels have the same tire cornering characteristics, and obtaining a dynamic equation of the vehicle model as follows:
Figure RE-207463DEST_PATH_IMAGE086
wherein the content of the first and second substances,
Figure RE-602979DEST_PATH_IMAGE087
Figure RE-809970DEST_PATH_IMAGE088
Figure RE-126682DEST_PATH_IMAGE089
in the above formula: m is the mass of the whole vehicle;
Figure RE-786333DEST_PATH_IMAGE090
respectively the equivalent lateral force of the front shaft and the rear shaft;
Figure RE-745062DEST_PATH_IMAGE091
the front axle equivalent longitudinal force;
Figure RE-806559DEST_PATH_IMAGE092
is the equivalent self-aligning moment of the shaft;
Figure RE-825330DEST_PATH_IMAGE093
rolling resistance is the yaw moment caused by load transfer for the left and right side wheels;
Figure RE-221546DEST_PATH_IMAGE094
the yaw moment between wheels caused by the front axle lateral force due to the front wheel corner;
Figure RE-452807DEST_PATH_IMAGE095
the actual additional yaw moment.
According to the stress analysis of the whole vehicle and the combination of the two-freedom-degree vehicle model, the method can be obtained as follows:
Figure RE-368810DEST_PATH_IMAGE097
in the formula:
Figure RE-558483DEST_PATH_IMAGE098
the motor torques of the left front wheel, the right front wheel, the left rear wheel and the right rear wheel are respectively; r is the tire radius;
Figure RE-192727DEST_PATH_IMAGE099
the front axle wheel track;
Figure RE-493258DEST_PATH_IMAGE100
is the rear axle track.
However, before calculating the torque of each motor, it is necessary to calculate the road surface adhesion coefficient
Figure RE-247456DEST_PATH_IMAGE101
Can be laid on the road surfaceCan provide maximum yaw moment
Figure RE-608030DEST_PATH_IMAGE102
For calculated additional yaw moment
Figure RE-729570DEST_PATH_IMAGE103
Making corrections if the maximum yaw moment that the ground can provide
Figure RE-568213DEST_PATH_IMAGE104
Greater than the calculated additional yaw moment
Figure RE-458809DEST_PATH_IMAGE103
According to the calculated additional yaw moment
Figure RE-911656DEST_PATH_IMAGE103
And (6) distributing. Conversely, if the ground can provide the maximum yaw moment
Figure RE-254912DEST_PATH_IMAGE104
Less than the calculated additional yaw moment
Figure RE-162826DEST_PATH_IMAGE103
According to the maximum yaw moment that the ground can provide
Figure RE-642348DEST_PATH_IMAGE104
The distribution is carried out, and excessive driving torque is prevented from being distributed to the driving wheels to cause excessive wheel slip.
The maximum yaw moment provided by the ground can be obtained by referring to the formula (1.5)
Figure RE-344725DEST_PATH_IMAGE104
Comprises the following steps:
Figure RE-427475DEST_PATH_IMAGE105
in the formula:
Figure RE-76762DEST_PATH_IMAGE106
the vertical loads of the left front wheel, the right front wheel, the left rear wheel and the right rear wheel are respectively.
Wherein the vertical load of each wheel is:
Figure RE-941950DEST_PATH_IMAGE107
whereby an actual additional yaw moment can be obtained
Figure RE-533337DEST_PATH_IMAGE108
Comprises the following steps:
Figure RE-100454DEST_PATH_IMAGE109
adding actual yaw moment
Figure RE-84590DEST_PATH_IMAGE108
And desired longitudinal drive torque
Figure RE-804285DEST_PATH_IMAGE110
And (1.4) and (1.5), the torque of each wheel of motor can be calculated, so that the motor torque distribution is carried out on the motor which is not failed.
Taking the failure mode of the left front wheel and the right rear wheel motor as an example, the torques of the left front wheel and the right rear wheel motor are zero, and the motor torques distributed by the right front wheel and the left rear wheel are as follows:
Figure RE-317306DEST_PATH_IMAGE111
in addition, the maximum longitudinal force of each wheel is also restrained by the external characteristics of the motor, the response speed, the road surface condition and the like, and the restraint conditions are as follows:
Figure RE-122451DEST_PATH_IMAGE112
in the formula (I), the compound is shown in the specification,
Figure RE-896896DEST_PATH_IMAGE113
the maximum torque that the motor can provide at the current rotation speed,
Figure RE-471097DEST_PATH_IMAGE114
is the maximum variation of the motor torque in one cycle.
The following detailed analysis is performed on the deceleration parking type failure control algorithm of the parking mode:
two sets of control methods are designed aiming at the straight running working condition and the turning working condition in the parking mode.
1. Under the straight-driving working condition, the motor which normally works on one side only can be applied with driving torque, so that the stress of the vehicle body is unbalanced, and a control method for setting the output torque of the motor which is not failed to work to be zero is adopted.
2. Under the turning working condition, the total driving torque loss is large, the vehicle speed is reduced suddenly, the steering radius is reduced sharply, the over-steering tendency is serious, the over-steering tendency can be improved by applying braking torque to the outer side wheels or applying driving torque to the inner side wheels, and the left-turning driving working condition is taken as an example:
(1) when the left two-wheel motor fails, severe oversteer can be caused, and by applying braking torque to the right wheels, the yaw moment can be reduced, and the oversteer tendency can be improved. In order to prevent the instability of the vehicle body caused by the sudden change of the torque, the braking torque is increased to the maximum braking torque which can be provided by the motor under the current state according to a certain slope until the vehicle is stable. The control method is adopted in the failure mode of the left two-wheel motor, the failure mode of the right two-wheel motor and the failure mode of the right two-wheel motor.
(2) When the motor of the two wheels on the right side fails, severe oversteer can be caused, and by applying driving torque to the wheels on the left side, the yaw moment can be reduced, and the oversteer tendency can be improved. In order to prevent the instability of the vehicle body caused by the moment mutation, the driving moment is kept unchanged after being reduced to zero according to a certain slope until the vehicle is stable. The control method is adopted in the right two-wheel motor failure mode, the right two-wheel left front wheel motor failure mode and the right two-wheel left rear wheel motor failure mode.
The above description is only an embodiment of the present invention, but the design concept of the present invention is not limited thereto, and any insubstantial modifications made by using the design concept should fall within the scope of infringing the present invention.

Claims (8)

1. A failure control method for an electric drive system of a four-wheel distributed drive passenger car is characterized by comprising the following steps: the method comprises the following steps:
(1) selecting the vehicle to enter a two-drive mode or a parking mode according to a failure mode of the electric drive system;
(2) and when the two-wheel drive mode is entered, motor torque distribution is carried out on the motor which is not failed:
(2.1) calculating different front wheel turning angles according to the reference ideal understeer degree US
Figure RE-790125DEST_PATH_IMAGE002
Vehicle speed
Figure RE-423231DEST_PATH_IMAGE004
Coefficient of adhesion to road surface
Figure RE-930436DEST_PATH_IMAGE006
Ideal yaw rate
Figure RE-405892DEST_PATH_IMAGE008
；
(2.2) calculating the ideal centroid slip angle by combining an integral estimation algorithm and an empirical formula of the centroid slip angle upper limit value
Figure RE-314943DEST_PATH_IMAGE010
；
(2.3) adopting a fuzzy control algorithm to calculate the yaw rate
Figure RE-853371DEST_PATH_IMAGE012
And centroid slip angle
Figure RE-51134DEST_PATH_IMAGE014
Error of (2)
Figure RE-395528DEST_PATH_IMAGE016
Calculating an additional yaw moment as an input variable
Figure RE-96768DEST_PATH_IMAGE018
；
(2.4) obtaining an output torque MAP (MAP) of the vehicle under different accelerator and vehicle speeds through off-line calculation, and obtaining expected longitudinal driving torque through interpolation of the opening of an accelerator pedal and the current vehicle speed according to the operation intention of a driver
Figure RE-133994DEST_PATH_IMAGE020
；
(2.5) combining additional yaw moment based on double-track two-degree-of-freedom nonlinear vehicle model
Figure RE-287895DEST_PATH_IMAGE022
And desired longitudinal drive torque
Figure RE-435979DEST_PATH_IMAGE024
And distributing motor torque to the motor which is not failed.
2. The failure control method of the electric drive system of the four-wheel distributed drive passenger car according to claim 1, characterized by comprising the following steps: in the step (1), the failure modes comprise a single-wheel motor failure mode, a same-side double-wheel motor failure mode, a different-side double-wheel motor failure mode and a multi-wheel motor failure mode; when the vehicle is in a single-wheel motor failure mode or a double-wheel motor failure mode on different sides, the vehicle enters a two-wheel drive mode; and when the vehicle is in the same-side failure of the double-wheel motor or the multi-wheel motor, the vehicle enters a parking mode.
3. The failure control method of the electric drive system of the four-wheel distributed drive passenger car according to claim 1 or 2, characterized in that: when the vehicle enters a parking mode, under the straight-ahead running working condition, a control method of setting the output torque of the motor which is not failed to be zero is adopted to realize deceleration parking; under the turning condition, a control method of applying braking torque to the outer wheels or applying driving torque to the inner wheels to improve the oversteering tendency is adopted to realize deceleration and stop.
4. The failure control method of the electric drive system of the four-wheel distributed drive passenger car according to claim 1, characterized by comprising the following steps: in the step (2.1), the ideal understeer degree is:
Figure RE-991726DEST_PATH_IMAGE026
。
5. the failure control method of the electric drive system of the four-wheel distributed drive passenger car according to claim 1, characterized by comprising the following steps: in the step (2.2), an empirical formula of the upper limit value of the centroid slip angle is as follows:
Figure RE-199853DEST_PATH_IMAGE028
。
6. the failure control method of the electric drive system of the four-wheel distributed drive passenger car according to claim 1, characterized by comprising the following steps: in the step (2.3), the yaw rate error
Figure RE-841050DEST_PATH_IMAGE030
Centroid slip angle error
Figure RE-527246DEST_PATH_IMAGE032
And additional yaw moment
Figure RE-468657DEST_PATH_IMAGE034
All adopt a triangular membership function and adopt a fuzzy solving mode of an area gravity center method to convert the output fuzzy quantity into accurateThereby obtaining an additional yaw moment
Figure RE-785369DEST_PATH_IMAGE036
。
7. The failure control method of the electric drive system of the four-wheel distributed drive passenger car according to claim 1, characterized by comprising the following steps: in the step (2.5), the dynamic equation of the vehicle model is as follows:
Figure RE-976179DEST_PATH_IMAGE038
。
8. the failure control method of the electric drive system of the four-wheel distributed drive passenger car according to claim 1, characterized by comprising the following steps: in the step (2.5), the road surface adhesion coefficient is required to be firstly determined
Figure RE-403749DEST_PATH_IMAGE040
Maximum yaw moment provided by lower road surface
Figure RE-730826DEST_PATH_IMAGE042
For calculated additional yaw moment
Figure RE-218439DEST_PATH_IMAGE044
Making a correction, said maximum yaw moment
Figure RE-896545DEST_PATH_IMAGE046
Comprises the following steps:
Figure RE-127806DEST_PATH_IMAGE048
in the formula:
Figure RE-574968DEST_PATH_IMAGE050
vertical loads of the left front wheel, the right front wheel, the left rear wheel and the right rear wheel respectively;
Figure RE-967903DEST_PATH_IMAGE052
the distance between the wheels of the front axle is,
Figure RE-133305DEST_PATH_IMAGE054
is the rear axle wheel base;
actual additional yaw moment
Figure RE-168257DEST_PATH_IMAGE056
Comprises the following steps:
Figure RE-673188DEST_PATH_IMAGE058
。
CN202010070125.7A 2020-01-21 2020-01-21 Failure control method for electric drive system of four-wheel distributed drive passenger car Pending CN111152661A (en)

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111746305A (en) * 2020-07-10 2020-10-09 江西科技学院 Energy-saving control method and system for wire-controlled four-wheel drive hub motor electric automobile
CN111746304A (en) * 2020-07-10 2020-10-09 上海工程技术大学 Distributed driving electric vehicle driving system control method based on failure state
CN111845734A (en) * 2020-07-31 2020-10-30 北京理工大学 Fault-tolerant tracking control method for four-wheel distributed electrically-driven automatic driving vehicle
CN112026748A (en) * 2020-07-27 2020-12-04 宁波吉利罗佑发动机零部件有限公司 Motor failure control method and device, electronic equipment and storage medium
CN112339882A (en) * 2020-10-10 2021-02-09 蓝普金睛（北京）科技有限公司 AGV moving platform system and method based on hub motor
CN112373293A (en) * 2020-09-11 2021-02-19 东风越野车有限公司 Fault processing method for distributed driving system of hub motor
CN112758094A (en) * 2021-01-04 2021-05-07 重庆长安汽车股份有限公司 Safe parking device and method for driving assistance system
CN112886905A (en) * 2021-04-13 2021-06-01 吉林大学 Rule-based fault-tolerant control method for driving eight-wheel electric wheel drive vehicle
CN113561794A (en) * 2021-08-05 2021-10-29 天津工程机械研究院有限公司 Drive control method and device of dual-motor pure electric loader
CN117416213A (en) * 2023-11-20 2024-01-19 燕山大学 Dual-mode coupling driving type automobile feedback braking failure composite control system and method

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2027099A6 (en) * 1990-03-21 1992-05-16 Univ De Oviedo Representada Po Self-locking electronic differential for electric traction vehicles
CN103318051A (en) * 2013-06-19 2013-09-25 电子科技大学 Failure control method for electric drive system of four-wheel drive electric vehicle
CN103419676A (en) * 2013-07-31 2013-12-04 浙江大学 Wheel type drive layering control system and method applied to electric car
CN108859862A (en) * 2018-03-22 2018-11-23 武汉理工大学 A kind of adaptive driving control system of distributed driving off-road vehicle
CN110395120A (en) * 2019-08-14 2019-11-01 厦门金龙联合汽车工业有限公司 A kind of weaving control method of four-wheel distribution driving car
CN110481338A (en) * 2019-07-23 2019-11-22 武汉理工大学 A kind of hub motor vehicle disablement control method and entire car controller

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2027099A6 (en) * 1990-03-21 1992-05-16 Univ De Oviedo Representada Po Self-locking electronic differential for electric traction vehicles
CN103318051A (en) * 2013-06-19 2013-09-25 电子科技大学 Failure control method for electric drive system of four-wheel drive electric vehicle
CN103419676A (en) * 2013-07-31 2013-12-04 浙江大学 Wheel type drive layering control system and method applied to electric car
CN108859862A (en) * 2018-03-22 2018-11-23 武汉理工大学 A kind of adaptive driving control system of distributed driving off-road vehicle
CN110481338A (en) * 2019-07-23 2019-11-22 武汉理工大学 A kind of hub motor vehicle disablement control method and entire car controller
CN110395120A (en) * 2019-08-14 2019-11-01 厦门金龙联合汽车工业有限公司 A kind of weaving control method of four-wheel distribution driving car

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111746305A (en) * 2020-07-10 2020-10-09 江西科技学院 Energy-saving control method and system for wire-controlled four-wheel drive hub motor electric automobile
CN111746304A (en) * 2020-07-10 2020-10-09 上海工程技术大学 Distributed driving electric vehicle driving system control method based on failure state
CN112026748B (en) * 2020-07-27 2022-03-08 宁波吉利罗佑发动机零部件有限公司 Motor failure control method and device, electronic equipment and storage medium
CN112026748A (en) * 2020-07-27 2020-12-04 宁波吉利罗佑发动机零部件有限公司 Motor failure control method and device, electronic equipment and storage medium
CN111845734B (en) * 2020-07-31 2021-03-02 北京理工大学 Fault-tolerant tracking control method for four-wheel distributed electrically-driven automatic driving vehicle
CN111845734A (en) * 2020-07-31 2020-10-30 北京理工大学 Fault-tolerant tracking control method for four-wheel distributed electrically-driven automatic driving vehicle
CN112373293A (en) * 2020-09-11 2021-02-19 东风越野车有限公司 Fault processing method for distributed driving system of hub motor
CN112339882A (en) * 2020-10-10 2021-02-09 蓝普金睛（北京）科技有限公司 AGV moving platform system and method based on hub motor
CN112758094A (en) * 2021-01-04 2021-05-07 重庆长安汽车股份有限公司 Safe parking device and method for driving assistance system
CN112886905A (en) * 2021-04-13 2021-06-01 吉林大学 Rule-based fault-tolerant control method for driving eight-wheel electric wheel drive vehicle
CN113561794A (en) * 2021-08-05 2021-10-29 天津工程机械研究院有限公司 Drive control method and device of dual-motor pure electric loader
CN113561794B (en) * 2021-08-05 2022-07-12 天津工程机械研究院有限公司 Drive control method and device of dual-motor pure electric loader
CN117416213A (en) * 2023-11-20 2024-01-19 燕山大学 Dual-mode coupling driving type automobile feedback braking failure composite control system and method

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Application publication date: 20200515