CN115805816B - Motor working point selection and gear shifting rule making method under regenerative braking - Google Patents
Motor working point selection and gear shifting rule making method under regenerative braking Download PDFInfo
- Publication number
- CN115805816B CN115805816B CN202310046380.1A CN202310046380A CN115805816B CN 115805816 B CN115805816 B CN 115805816B CN 202310046380 A CN202310046380 A CN 202310046380A CN 115805816 B CN115805816 B CN 115805816B
- Authority
- CN
- China
- Prior art keywords
- power
- braking force
- braking
- motor
- gear
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- 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 relates to the field of control of pure electric vehicles and hybrid electric vehicles, and discloses a method for selecting a working point of a motor and formulating a gear shifting rule under regenerative braking, which comprises the following steps: performing coordination control on the distribution of the wheel power-on mechanism power and the hydraulic braking force based on whether the wheel power-on mechanism power can meet the required braking force; analyzing the influence of the selection of different motor working points before and after gear shifting on the energy recovery rate in the energy recovery process and the selection strategy of the motor working points before and after gear shifting under different gear shifting working conditions; taking a selection strategy of a gear shifting working point, the rotating speed of a motor and the recovery power of a battery as constraint conditions for formulating a gear shifting rule, and formulating the gear shifting rule in the energy recovery process based on economy; obtaining an optimal gear distribution map based on economy according to the gear shifting rule; during the running process of the vehicle, the gear shifting operation can be executed according to the optimal gear distribution diagram. The invention can meet the braking requirement and improve the recovered energy on the premise of braking smoothness.
Description
Technical Field
The invention relates to the field of control of pure electric vehicles and hybrid electric vehicles, and particularly discloses a method for selecting a working point of a motor and formulating a gear shifting rule under regenerative braking.
Background
In order to cope with global energy crisis and environmental pollution, automobile power assemblies are gradually electrified, and among them, new energy vehicles, mainly represented by pure electric vehicles/hybrid electric vehicles (EV/HEV), are rapidly developing. Pure electric vehicles/hybrid electric vehicles (EV/HEV) have huge potential in the aspects of reducing fuel consumption, pollution emission and the like, and are the focus of the current automobile industry. The recovery of braking energy is a main way for realizing energy saving of a pure electric vehicle/hybrid electric vehicle (EV/HEV), so that the problems of improving the recovery energy of braking, ensuring the safety of the braking process and the like are particularly concerned.
In the energy recovery process, only a braking energy recovery system is researched, other systems are not coupled with the braking energy recovery system, and the driving range of a pure electric vehicle/hybrid electric vehicle (EV/HEV) cannot be increased to the maximum extent. At present, for a pure electric vehicle/hybrid electric vehicle (EV/HEV) matched with an automatic gearbox, distribution of wheel end braking and motor braking under a gear shifting rule is not involved when braking force is distributed in the process of energy recovery. The gear shifting is carried out in the braking process, so that the re-acceleration capability of the automobile can be enhanced, and the braking energy recovery capability can be improved. Therefore, it is necessary to design a method for making a shift schedule in an energy recovery process to ensure energy recovery rate and re-acceleration capability.
For example, chinese invention patent CN105922987B discloses a downshift strategy in the regenerative braking process of HEV/EV, which determines that the vehicle speed is zero or the brake pedal opening is zero, and when the battery state of charge is smaller than the battery upper limit threshold, the expected braking strength is obtained according to the brake pedal opening; when the expected braking intensity is smaller than the braking intensity threshold value or the current gear is not 1 gear, calculating the maximum braking force provided by the driving motor under the current gear; determining the output torque of the driving motor according to the smaller value of the maximum braking force and the required braking force; calculating the increasing rate of the battery state of charge under the current gear according to the torque; taking the maximum value of the increasing rates of the battery state of charge corresponding to the current gear and the gear lower than the current gear, and comparing the maximum value with the increasing rate of the battery state of charge of the current gear; if the former is small, the gear is changed to the gear corresponding to the maximum value. The invention can improve the re-acceleration capability of the automobile and the energy recovered by regenerative braking, thereby improving the dynamic property and the fuel economy of the automobile. However, the invention does not relate to setting the distribution of electro-hydraulic (motor and hydraulic) braking force of the vehicle in the braking process according to the situation according to whether the electric braking force on the wheel meets the required braking force, and does not realize the selection of the working point of the motor; and when the braking force provided by the wheel electric braking force in the whole braking process is not involved, the wheel electric braking force under the current gear is compared with the required braking force, and the wheel electric braking force after gear shifting is compared with the required braking force. Therefore, the invention can not effectively ensure the energy recovery rate.
In addition, under most braking conditions, a driver often has an acceleration demand after short braking, and when the vehicle is braked from a high speed to a low speed and the gear of the transmission is still kept at a high gear, the brake pedal is pressed at the moment, so that the phenomenon of vehicle acceleration power delay can be generated even if the transmission is immediately downshifted. Based on the above discussed conditions, the prior art cannot comprehensively consider the method for making the gear shifting rule by coordinating and controlling the wheel end braking and the motor braking, and cannot improve the re-acceleration capability of the vehicle after braking and effectively increase the energy recovery amount.
Disclosure of Invention
The invention aims to provide a method for selecting a working point of a motor and making a gear shifting rule under regenerative braking aiming at a front-wheel drive vehicle aiming at the corresponding defects of the prior art, and the method can effectively increase the energy recovery amount, improve the re-acceleration capability after braking and ensure the comfort of the braking process.
The technical scheme of the invention is as follows:
the method for selecting the working point of the motor and making the gear shifting rule under the regenerative braking is suitable for a front-driving vehicle, namely a vehicle with the electric mechanism power on wheels only acting on the front axle of the wheels; the method specifically comprises the following steps:
s1, making a comprehensive braking force distribution strategy
Based on the judgment condition whether the wheel power-on mechanism power can meet the required braking force, the distribution of the wheel power-on mechanism power and the hydraulic braking force is coordinately controlled: firstly, the braking force of the wheel motor can meet the required braking force, and the hydraulic braking force is not needed; secondly, the electric braking power on the wheel is not enough to meet the required braking force, and the insufficient part is supplemented by the hydraulic braking force;
s2, selection strategy of motor working point during gear shifting
According to the two cases in S1, the motor working point is selected as follows: firstly, the power of the electric motor on the wheel can meet the required braking force, the working point of the electric motor is moved to an equal-power high-efficiency interval along an equal-power curve through gear shifting, and the power of the electric motor on the wheel is unchanged; secondly, the power of the electric motor on the wheel is not enough to meet the required braking force, the working point of the electric motor is transferred to a high-power region of the electric motor through gear shifting, and the power of the electric motor on the wheel is changed at the moment;
s3, determining a gear shifting rule in the energy recovery process, and executing gear shifting
Taking the selection strategy formulated in the S2 as one of the constraint conditions formulated by the gear shifting rule, namely the constraint of the electric mechanism power and the required braking force on the maximum wheels before and after gear shifting on the selection of the working point of the motor during gear shifting; in addition, the constraint conditions also comprise the rotating speed of the motor and the recovery power of the battery; and then, based on the constraint conditions, a gear shifting rule in the energy recovery process based on economy is formulated and gear shifting is carried out by combining the actual situation in the driving process.
Further, in S1, the distribution of the wheel electric braking force and the hydraulic braking force is coordinately controlled, and according to the magnitude of the braking strength under different braking conditions, the following five situations are divided:
(1) At the time of light braking, the braking strengthzSatisfies the condition of 0 or morez<z A When, only the braking force is provided on the front axle,zthe brake strength is represented, and the value is determined according to the opening degree of a brake pedal and is between 0 and 1;z A a threshold value representing the lowest brake intensity during light braking, and the required braking force of the front axle and the rear axle is determined according to the following formula:
wherein the content of the first and second substances,z A the following equation is used to obtain:
in the formula (I), the compound is shown in the specification,F Brake,Front andF Brake,Rear respectively representing the required braking forces of the front and rear axles,mas the mass of the vehicle,L a andL b respectively representing the distance of the vehicle's center of mass to the front and rear axles,gwhich represents the acceleration of the force of gravity,h g representing vehicle center of mass height;
if the electric braking force on the wheel is enough to meet the braking force demand of the front axle, the braking force demand on the front axle and the rear axle is formed as follows:
in the formula (I), the compound is shown in the specification,F MotorBrake indicating the electric machine dynamics on the wheel,F HydraulicBrake,Front a hydraulic braking force of the front wheels is indicated,F HydraulicBrake,Rear indicating a rear wheel hydraulic braking force;
if the electric braking power on the wheels is not enough to meet the braking force required by the front axle, additional braking force is provided through the hydraulic braking force of the front wheels; the required braking force on the front and rear axles is constituted as follows:
(2) When braking intensityzSatisfy the requirement ofz A ≤z<z B In whichz B =0.5, the front and rear axle demand brake force distribution is as follows:
in the formula (I), the compound is shown in the specification,k b =0.99 represents a braking force distribution safety factor;
if the electric braking force on the wheel is enough to meet the braking force required by the front axle, the required braking force on the front axle and the rear axle is formed as follows:
if the electric braking power on the wheels is not enough to meet the braking force required by the front axle, additional braking force is provided through the hydraulic braking force of the front wheels; the required braking force on the front and rear shafts is formed as follows:
(3) When braking intensityzSatisfy the requirement ofz B ≤z<z C In the process of (a), wherein,z C =0.65, the required braking force distribution on the front and rear axles is as follows:
if the electric braking force on the wheel is enough to meet the braking force demand of the front axle, the braking force demand on the front axle and the rear axle is formed as follows:
if the electric braking power on the wheels is not enough to meet the braking force required by the front axle, additional braking force is provided by the hydraulic braking power on the front wheel; the required braking force on the front and rear axles is constituted as follows:
(4) When the strength of brakingzSatisfy the requirement ofz C ≤z<z D In whichz D =The required braking force distribution on the front and rear axles is as follows:
wherein the content of the first and second substances,
represents a road adhesion coefficient;
if the electric braking force on the wheel is enough to meet the braking force demand of the front axle, the braking force demand on the front axle and the rear axle is formed as follows:
if the electric braking power on the wheels is not enough to meet the braking force required by the front axle, additional braking force is provided by the hydraulic braking power on the front wheel; the required braking force on the front and rear axles is constituted as follows:
(5) When in usez≥z D When the vehicle is in an emergency braking state, in order to ensure the stability of the vehicle in the braking process, the motor does not participate in braking in the emergency braking state, namely the front wheel braking force is provided by the front wheel hydraulic braking force, and the required braking forces on the front shaft and the rear shaft are distributed according to the following formula:
the required braking force on the front and rear axles is constituted as follows:
further, in S2, the selection of the operating point of the motor during gear shifting is divided into the following three cases:
case 1: when the electric braking power on the wheels before and after gear shifting is more than or equal to the required braking power, namely the electric braking power reserve value on the front wheel of gear shifting
And a brake braking power reserve value on the rear wheels of the gear shift>
Are all bigIn response to demand braking power>
(ii) a The power value of the working point of the motor is->
The equal power line is moved to a rotating speed value of->
A corresponding position;
case 2: when the electric braking power on the wheels before and after shifting is less than the required braking power, namely the electric braking power reserve value on the front wheel of shifting
And a brake braking power reserve value on the rear wheels of the gear shift>
Are all less than the required braking power
(ii) a The working point of the motor is firstly along the power value->
The equal power line is moved to a rotating speed value of->
Corresponding to the position, and then the rotating speed value is->
When the equal rotating speed line moves to the brake power reserve value on the rear gear of the gear shifting
The position of (a);
case 3: when the electric braking power on the front gear is less than the required braking force and the electric braking power on the rear gear is more than or equal to the required braking force, namely the electric braking power reserve value on the front gear is
Less than required braking power/>
The brake power reserve value on the rear wheel of the gear shift is pick-up>
Greater than or equal to the required braking power>
(ii) a The working point of the motor is firstly along the power value of->
The equal power line is moved to a rotating speed value of->
Corresponding position, again along the rotation speed value of
Is moved to the required braking power->
The position of (a);
in the case of the cases 1-3,
indicating before a shift>
Indicates after a gear shift, is engaged>
The rotating speed of the motor in the high-efficiency interval after gear shifting.
Further, in S3, the specific steps of determining the shift schedule in the energy recovery process are as follows:
s3-1: when the vehicle controller identifies that the driver needs to brake, the vehicle state parameters before gear shifting are obtained, including the current vehicle speed
The current brake strength->
Current vehicle gear & -4>
Before shifting gear the battery recovers power>
Battery state of charge->
(ii) a Judges the current vehicle speed->
If the value is 0, returning to S3-1 if the value is 0; if the current vehicle speed is greater or less>
If not, the current battery state of charge is continuously judged>
Whether or not it is greater than or equal to a maximum value of the state of charge of the battery>
If the current battery state of charge->
Greater than or equal to the maximum value of the charge state of the battery>
Returning to S3-1; if the current battery state of charge
Less than maximum battery state of charge>
Then continuously judging the current braking strength->
If it is 0, if the current brake strength->
If the value is 0, returning to S3-1; if the current brake strength>
If not, continuing to execute S3-2; wherein the subscript->
Indicates that the current cycle is th>
Performing secondary circulation;
s3-2: the gear shifting rule is restrained based on the motor speed: calculating a current gear based on a transmission ratio
Change to the other gears>
Corresponding motor speed->
(ii) a According to the motor speed->
Obtaining the corresponding maximum motor power
(ii) a Determination of the requested braking power ^ of the vehicle from the requested braking force>
Judgment is made>
Whether or not it is less than or equal to the maximum motor speed>
(ii) a If yes, jumping to S3-3; otherwise, no shift is performed and the shift is asserted>
And returning to S3-1;
s3-3: the gear shifting rule is restrained based on the selection strategy of the motor working point of S2;
s3-4: obtaining gears according to constraint conditions
The corresponding motor recovery power->
(ii) a Motor recovered power->
Equal to the braking demand power of the wheel on motor>
To the maximum motor power
Wherein it is greater than the predetermined value, wherein>
In the formula (I), wherein,
for the motor speed after the gear shift, ->
For the motor speed after shifting>
Lower maximum motor torque;
s3-5: distributing electric braking power and hydraulic braking force on the wheels based on the comprehensive braking force distribution strategy of S1:
on-wheel brake power reserve if before gear shift
And a post-shift on-wheel brake power reserve>
Are all greater than or equal to the braking power required by the vehicle>
The braking force of the motor on the wheel and the hydraulic braking force are distributed according to the condition that the braking force of the motor on the wheel in the S1 can meet the required braking force;
brake power reserve on wheels if before gear shift
Or the on-wheel brake power reserve after a gear change->
Less than the braking power demanded by the vehicle>
If the power of the electric motor on the wheel and the hydraulic braking force are not enough to meet the requirement of the braking force in the S1, distributing the power of the electric motor on the wheel and the hydraulic braking force;
s3-6: according to the current gear in S3-2
Motor speed of each gear shift outside->
And motor torque
Obtaining the current gear>
The braking efficiency of the motor on each gear wheel outside>
And the recovery power of each battery is->
；/>
S3-7: the gear shifting rule is constrained based on the battery recovery power: selecting the current gear
Battery recovery power of other gears>
Is greater than or equal to>
And in combination with pre-shift battery recovery power>
Make a comparison if->
Greater than or equal to>
Jump to S3-8, otherwise make ^ er>
And returning to S3-1;
s3-8: shifting gears with a target gear of
A corresponding gear; returns to S3-1 upon completion of the shift and orders->
The number of shifts is accumulated.
Further, the constraint conditions in S3 are specifically: if the current maximum motor power
Greater than the demanded braking power of the vehicle->
The power value of the working point of the motor is pick>
Moving the power line to a rotating speed value of
A corresponding position; otherwise, a switched brake power reserve value is detected on the wheel after the gear shift>
And the required braking power of the vehicle->
If is>
＞/>
If the motor operating point is greater than or equal to the power value>
When the equal power line is moved to a rotating speed value of->
Corresponding to the position, and then the rotating speed value is->
The corresponding speed line is moved to the required braking power ≥ of the vehicle>
(ii) a If/or>
</>
Then the working point of the motor is along the power value->
The equal power line is moved to a rotating speed value of->
Corresponding to the position, and then the rotating speed value is->
The corresponding speed line is moved to the on-wheel motor braking power reserve value->
。
Further, the present invention also includes:
s4, based on the gear shifting rule formulated in the S3, making an optimal gear distribution diagram
And according to the gear shifting rule formulated in the S3, setting the opening degree of a brake pedal from 100% to 0% by taking the vehicle speed of 200km/h as an initial speed, traversing gears corresponding to the maximum battery recovery power under different vehicle speeds and brake pedal opening degrees, namely the optimal gears, and further obtaining an optimal gear distribution map under different vehicle speeds and brake pedal opening degrees based on economy.
Further, when the optimal gear distribution diagram is manufactured, the step length of the vehicle speed is set to be 1km/h, and the step length of the opening degree of the brake pedal is set to be 1%.
Compared with the prior art, the invention has the beneficial effects that:
(1) According to the invention, the distribution of the electro-hydraulic braking force of the vehicle in the braking process is formulated according to the condition whether the braking force of the wheel motor meets the required braking force, so that the selection of the working point of the motor is realized; when the braking force provided by the wheel power-on mechanism power in the whole braking process is researched, the wheel power-on mechanism power under the current gear is compared with the required braking force, and the comparison between the wheel power-on mechanism power after gear shifting and the required braking force is also considered.
(2) By means of the established hydraulic braking and motor braking coordinated control gear shifting rule method, the energy recovery rate of the vehicle is improved, the reacceleration capability of the vehicle is improved, the driving safety is improved, the comfort of the braking process is guaranteed, and the driving range of a pure electric vehicle/hybrid electric vehicle (EV/HEV) is prolonged.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only some embodiments described in the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a diagram of a comprehensive brake force distribution strategy of the present invention;
FIG. 2 is a schematic diagram of the energy recovery process step 1 shift motor operating point selection of the present invention;
FIG. 3 is a schematic diagram of the energy recovery process step 2 shift motor operating point selection of the present invention;
FIG. 4 is a schematic diagram of the energy recovery process step 3 shift motor operating point selection of the present invention;
FIG. 5 is a shift operating point selection flow chart of the energy recovery process of the present invention;
FIG. 6 is an economy based shift schedule flow chart of the present invention;
fig. 7 is an economy-based optimal gear profile for the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, 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 some, but not all, embodiments of the present invention. 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.
A method for selecting a motor working point and making a gear shifting rule under regenerative braking considering hydraulic braking and motor braking coordinated control comprises four steps, namely, a braking force distribution strategy is integrated, the motor working point is selected in a braking energy recovery process, the gear shifting rule is made and an optimal gear distribution diagram with economy is made in the braking energy recovery process, and gear shifting is carried out. The relation is presented among the four steps, which are described in detail below:
1. integrated brake force distribution strategy
The braking force distribution strategy divides coordinated distribution of hydraulic braking and motor braking into five situations according to the magnitude of braking strength under different braking conditions, wherein the distribution of the motor braking force and the hydraulic braking force under the first four situations can be further generalized into two situations: the power of the electric motor on the wheel can meet the required braking force, and the power of the electric motor on the wheel is not enough to meet the required braking force, and the insufficient part is supplemented by front and rear hydraulic braking forces. The specific electro-hydraulic brake force distribution is as follows:
(1) At light braking, the braking strengthzSatisfies the condition of 0 to lessz<z A When, only the braking force is provided on the front axle,zthe braking strength is represented and is determined according to the opening degree of a brake pedal, and the value is between 0 and 1;z A a threshold value representing the lowest brake intensity during light braking, and the required braking force of the front axle and the rear axle is determined according to the following formula:
if the electric braking force on the wheel can meet the total required braking force, the front and rear braking force are distributed as follows:
if the electric braking power on the wheels is less than the total required braking force, additional braking force is provided by the front axle hydraulic braking force. The braking force distribution on the front and rear shafts is as follows:
(2) When the braking strength is satisfiedz A ≤z<z B In whichz B The braking strength is high, in order to recover the braking energy as much as possible and ensure the stability in the braking process, the braking force of the front and rear axles is distributed along the curve of the lower limit of the ECE regulation limit range, and the required braking force of the front and rear axles is distributed as follows:
in the formula (I), the compound is shown in the specification,k b =0.99 represents the braking force distribution safety factor;
if the braking force of the electric motor on the wheel can meet the braking force required by the front axle, the braking force distribution on the front axle and the rear axle is as follows:
if the electric braking force on the wheels is less than the required braking force of the front axle, additional braking force is provided by the front axle hydraulic braking force. The braking force distribution on the front and rear shafts is as follows:
(3) When the brake strength is sufficientz B ≤z<z C In the above-mentioned order, wherein,z C =0.65, segment BC in fig. 1, when the front-rear required braking force distribution is as follows:
if the braking force of the electric motor on the wheel can meet the braking force required by the front axle, the braking force distribution on the front axle and the rear axle is as follows:
if the electric braking force on the wheel is smaller than the braking force required by the front axle, the additional braking force of the front axle is provided through the hydraulic braking force of the front axle; the braking force distribution on the front and rear shafts is as follows:
(4) When in usez C ≤z<z D In whichz D =1, section CD in FIG. 1, distributes front and rear axle demand brake force along a CD curve near the lower limit of the I-curve regulatory range:
if the electric braking force on the wheel can meet the braking force required by the front axle, the braking force on the front axle and the rear axle is distributed according to the following formula:
if the electric braking force on the wheel is smaller than the braking force required by the front axle, additional braking force is provided through the hydraulic braking force of the front axle; the braking force distribution on the front and rear shafts is as follows:
(5) When z is more than or equal to z D When the vehicle is in emergency braking state, the vehicle adopts full hydraulic braking. Since the transient response speed of the motor generally lags behind the hydraulic brake system, it is difficult to ensure control accuracy when triggering the brake anti-lock system. In order to ensure the stability of the vehicle in the braking process, the motor does not participate in braking in an emergency braking state, namely, the braking force of the front wheel brake is completely provided by the mechanical hydraulic brake. When the full hydraulic brake is carried out, the braking force on the front shaft and the rear shaft is distributed according to the following formula:
the required braking force on the front and rear axles is constituted as follows:
in conclusion, when the braking strength is low, the comprehensive braking force distribution strategy adopts a distribution mode that the power of the on-wheel motor occupies a large ratio, so that the braking power of the motor is improved, and the recovered energy is improved; and when the braking strength is high, an ideal braking force distribution strategy is adopted to ensure the balance of braking stability and braking force distribution of the front axle and the rear axle. Therefore, the formulated comprehensive braking force distribution strategy can improve the energy recovery rate on the premise of ensuring the braking stability.
2. Brake energy recovery process shift operating point selection
In the comprehensive braking force distribution strategy, two situations exist in the distribution of motor braking force and hydraulic braking force, wherein the motor braking force on the wheel can meet the required braking force, the motor braking force is not enough to meet the required braking force, and the insufficient part is supplemented by the front hydraulic braking force and the rear hydraulic braking force. For the first situation, the working point of the motor can be adjusted to be in an equal-power high-efficiency interval through gear shifting so as to achieve the improvement of the energy recovery rate, and the power of the motor on the wheel is unchanged. For the second situation, the working point of the motor can be adjusted to be shifted to a high-power interval through gear shifting so as to improve the energy recovery rate, and the power of the motor on the wheel changes at the moment. Therefore, the module mainly aims at the principle of how to select the working point of the motor in the whole braking process under the comprehensive braking force distribution strategy. The principle is divided into three conditions according to the difference between the electric braking force and the required braking force on the front and rear gear shifting wheels, and the three conditions are as follows: the electric braking force on the wheels before and after gear shifting is more than or equal to the required braking force; the electric braking force on the wheels before and after gear shifting is less than the required braking force; the electric mechanism power on the front gear shifting wheel is less than the required braking force, and the electric mechanism power on the rear gear shifting wheel is more than or equal to the required braking force. From the analysis, it is summarized as a mechanism of selection of the shift operating point during energy recovery, which is explained next with reference to fig. 2, 3, 4 and 5, in which fig. 2-5 represent maps of electric machines, known for each vehicle; the relationship between efficiency, speed, torque and power may be displayed. Taking a certain rotating speed as an example, different torques of the corresponding motor at the rotating speed are multiplied by the different torques of the motor at the rotating speed, so that different powers of the corresponding motor at the rotating speed can be obtained; changing different rotating speeds, different powers of the motor at each rotating speed can be obtained, points with equal power are connected, namely equal power lines of the motor, such as equal power curves shown in fig. 2-5, and the power is increased in the 6 equal power curves in fig. 2-5 from top to bottom, specifically, the uppermost equal power line is 10kw, and the uppermost equal power line is 20kw, 30kw, 40kw, 50kw and 60kw respectively in sequence from bottom to top.
The selection of the working point of the motor during gear shifting is divided into the following three conditions:
case 1: when the electric braking power on the wheels before and after shifting is larger than or equal to the required braking power, namely the electric braking power reserve value on the front wheel of shifting
And a brake braking power reserve value on the rear wheels of the gear shift>
Are all greater than the required braking power>
(ii) a The power value of the working point of the motor is->
When the equal power line is moved to a rotating speed value of->
A corresponding position; as indicated by the ab line in fig. 2.
Case 2: when the electric braking power on the wheels before and after shifting is less than the required braking power, namely the electric braking power reserve value on the front wheel of shifting
And a brake braking power reserve value on the rear wheels of the gear shift>
Are all less than the required braking power>
(ii) a The working point of the motor is firstly along the power value of->
The equal power line is moved to a rotating speed value of->
Corresponding position, and rotating speed value of->
When the equal rotating speed line moves to the brake power reserve value on the rear gear of the gear shifting
The position of (a); as indicated by the ab and bd lines in fig. 3.
Case 3: when the electric braking power on the front gear is less than the required braking force and the electric braking power on the rear gear is more than or equal to the required braking force, namely the electric braking power reserve value on the front gear is
Less than the required braking power>
The brake power reserve value on the rear wheel of the gear shift is pick-up>
Greater than or equal to the braking power required>
(ii) a The working point of the motor is firstly along the power value of->
The equal power line is moved to a rotating speed value of->
Corresponding position, again along the rotation speed value of
Is moved to the required braking power>
The position of (a); as indicated by the ab and bc lines in fig. 4.
The three situations are made into a flow chart of energy recovery process gear-shifting working point selection as shown in fig. 5, and relevant parameters of the motor are restricted when the vehicle runs under different braking conditions, so that the target requirement is met.
3. Selection of gear shifting rules based on economic energy recovery process
The selection of the shift operating point in the energy recovery process has three conditions, and the essence of the three conditions is the restriction of the maximum motor braking power and the required braking power on the selection of the shift operating point before and after the gear shifting. For the formulation of a gear shifting rule, firstly, the selection constraint conditions of the maximum motor braking power and the required braking power to the gear shifting working point before and after gear shifting are obtained according to the selection of the gear shifting working point in the energy recovery process, and for the maximum motor braking power, the transfer of the gear shifting working point is constrained, so that the motor braking power is influenced. For the required braking power, the shifting of the gear shifting working point is also restrained, and the motor braking power is influenced. Under the condition that the two constraint conditions are met, the motor after gear shifting uses the battery recovery power of each gear as a judgment condition, the maximum battery recovery power and the corresponding gear are obtained by traversing each gear, and the gear shifting rule is formulated based on the calculation result. The steps for the economy-based shift schedule making will now be described, and a flowchart is shown in fig. 6.
Step 1: when the vehicle controller identifies that the driver needs to brake, the vehicle state parameters before gear shifting are obtained, including the current vehicle speed
Current brake strength>
The current vehicle gear->
Before shifting gear the battery recovers power>
Battery state of charge->
(ii) a JudgmentPick up the current vehicle speed>
If the value is 0, returning to the step 1 if the value is 0; if the current vehicle speed is greater or less>
If not 0, the current state of charge of the battery is continuously judged>
Whether or not it is greater than or equal to the maximum value of the state of charge of the battery>
If the current battery state of charge->
Greater than or equal to the maximum value of the charge state of the battery>
Returning to the step 1; if the current battery state of charge
Less than maximum battery state of charge->
Then continuously judging the current braking strength->
If it is 0, if the current brake strength->
If the value is 0, returning to the step 1; if the current brake strength->
If not, continuing to execute the step 2; wherein the subscript->
Indicating that the current cycle is ^ h>
Performing secondary circulation;
step 2: the gear shifting rule is constrained based on the motor speed: calculating a current gear based on a transmission ratio
Change to the other gears>
Corresponding motor speed->
(ii) a Based on the motor speed>
Obtain the corresponding maximum motor power->
(ii) a Determination of the requested braking power ^ of the vehicle from the requested braking force>
Judgment is made>
Whether or not it is less than or equal to the maximum motor speed>
(ii) a If yes, jumping to the step 3; otherwise, no shift is performed and the shift is asserted>
And returns to step 1.
And 3, step 3: and constraining the gear shifting rule based on the selection strategy of the working point of the motor.
And 4, step 4: obtaining gears according to constraint conditions
Corresponding motor recovery power>
(ii) a Motor recovered power->
Equal to the braking demand power of the wheel on motor>
To the maximum motor power
Wherein it is greater than the predetermined value, wherein>
In the formula (I), the reaction is carried out,
for the speed of the motor after the gear shift>
For the motor speed after shifting>
Maximum motor torque below.
And 5: distributing electric braking force and hydraulic braking force on the wheels based on a comprehensive braking force distribution strategy:
on-wheel brake power reserve if before gear shift
And a switched on-wheel brake power reserve->
Are all greater than or equal to the braking power required by the vehicle>
The braking force of the motor on the wheel and the hydraulic braking force are distributed according to the condition that the braking force of the motor on the wheel in the S1 can meet the required braking force;
brake power reserve on wheels if before gear shift
Or the on-wheel brake power reserve after a gear change->
Less than the braking power demanded by the vehicle>
Then the on-wheel electric machine power and the hydraulic braking force are distributed according to the condition in S1 that the on-wheel electric machine power is insufficient to meet the required braking force.
Step 6: according to the current gear in step 2
Motor speed of each gear shift outside->
And motor torque
Obtaining the current gear>
Braking efficiency of motor on each gear wheel outside>
And the recovery power of each battery is->
。
And 7: the gear shifting rule is restrained based on the recovered power of the battery: selecting the current gear
Battery recovery power of other gears>
In (b) is maximum>
And in combination with pre-shift battery recovery power>
Make a comparison if/>
Greater than or equal to>
Jump to step 8, otherwise make->
And returning to the step 1.
And 8: shifting gears with a target gear of
A corresponding gear; after the gear shift is completed, the procedure returns to step 1 and is asserted>
The number of shifts is accumulated.
4. Executing downshift operation based on optimal gear distribution of economy
And 3, setting the opening degree of a brake pedal from 100% to 0% by adopting the economical energy recovery process gear shifting rule set in the step 3 and taking the vehicle speed of 200km/h as the initial speed, and traversing and calculating the gear corresponding to the maximum battery braking power to obtain the economical optimal gear distribution. In the energy recovery process, the vehicle speed is gradually reduced, the vehicle state shows a trend from right to left, and when the vehicle speed and the brake pedal opening degree are obtained, the gear under the current working condition is obtained.
As shown in fig. 7, the step length of the vehicle speed is 1km/h, the step length of the pedal opening is 1%, each cell represents a gear corresponding to the highest energy recovery rate under the corresponding vehicle speed and pedal opening, and when the vehicle state changes, the gear changes. The method is characterized in that the brake pedal opening degree is 10% as a limit, when the brake pedal opening degree is larger than 10%, the gear shifting rule is similar to a single-parameter gear shifting rule, namely the gear shifting time is only related to the vehicle speed, the motor works in a high-power range at the moment, and the requirement of downshift mainly comes from the reduction of the motor limit power caused by the reduction of the motor rotating speed. When the opening degree of the brake pedal is less than 10%, the gear shifting rule is not only related to the vehicle speed but also related to the opening degree of the brake pedal, namely the gear shifting opportunities of different opening degrees of the brake pedal under the same vehicle speed are different, at the moment, the motor works in a low-power interval, and the requirement of gear reduction mainly comes from the fact that the working point of the motor is shifted from the low-power low-efficiency interval to the low-power high-efficiency interval.
It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.
Claims (6)
1. The method for selecting the working point of the motor and making the gear shifting rule under the regenerative braking is characterized by comprising the following steps of:
s1, making a comprehensive braking force distribution strategy
Based on the judgment condition whether the wheel power-on mechanism power can meet the required braking force, the distribution of the wheel power-on mechanism power and the hydraulic braking force is coordinately controlled: firstly, the braking force of the wheel motor can meet the required braking force, and the hydraulic braking force is not needed; secondly, the electric braking power on the wheel is not enough to meet the required braking force, and the insufficient part is supplemented by the hydraulic braking force;
s2, selection strategy of motor working point during gear shifting
According to the two cases in S1, the motor working point is selected as follows: firstly, the power of the wheel-mounted motor can meet the required braking force, the working point of the motor is moved to an equal-power high-efficiency interval along an equal-power curve through gear shifting, and the power of the wheel-mounted motor is unchanged; secondly, the power of the on-wheel motor is insufficient to meet the required braking force, the working point of the motor is shifted to a high-power section of the motor through gear shifting, and the power of the on-wheel motor is changed at the moment;
s3, determining a gear shifting rule in the energy recovery process, and executing gear shifting
Taking the selection strategy formulated in the S2 as one of the constraint conditions formulated by the gear shifting rule, namely the constraint of the electric mechanism power and the required braking force on the maximum wheels before and after gear shifting on the selection of the working point of the motor during gear shifting; in addition, the constraint conditions also comprise the rotating speed of the motor and the recovery power of the battery; then, based on constraint conditions, formulating a gear shifting rule in an energy recovery process based on economy and shifting gears by combining actual conditions in a driving process;
in S1, the distribution of the electric braking force and the hydraulic braking force on the wheel is coordinately controlled, and the following five situations are divided according to the braking strength under different braking conditions:
(1) At light braking, the braking strengthzSatisfies the conditions
When, only the braking force is provided on the front axle,zthe brake strength is represented, and the value is determined according to the opening degree of a brake pedal and is between 0 and 1;z A a threshold value representing the lowest brake intensity during light braking, and the required brake force of the front axle and the rear axle is determined according to the following formula:
wherein the content of the first and second substances,z A the following equation is used to obtain:
in the formula (I), the compound is shown in the specification,F Brake,Front andF Brake,Rear respectively representing the required braking forces of the front and rear axles,mas the mass of the vehicle,L a andL b respectively representing the distance of the vehicle's center of mass to the front and rear axles,gwhich represents the acceleration of the force of gravity,h g representing vehicle center of mass height;
if the electric braking force on the wheel is enough to meet the braking force demand of the front axle, the braking force demand on the front axle and the rear axle is formed as follows:
in the formula (I), the compound is shown in the specification,F MotorBrake indicating the electric machine dynamics on the wheel,F HydraulicBrake,Front a hydraulic braking force of the front wheels is indicated,F HydraulicBrake,Rear indicating a rear wheel hydraulic braking force;
if the electric braking power on the wheels is not enough to meet the braking force required by the front axle, additional braking force is provided through the hydraulic braking force of the front wheels; the required braking force on the front and rear axles is constituted as follows:
F MotorBrake_max representing maximum on-wheel electric machine dynamics;
(2) When the strength of brakingzSatisfy the requirement of
In whichz B =0.5, the front and rear axle required braking force distribution is as follows:
in the formula (I), the compound is shown in the specification,k b =0.99 represents the braking force distribution safety factor;
if the electric braking force on the wheel is enough to meet the braking force required by the front axle, the required braking force on the front axle and the rear axle is formed as follows:
if the electric braking power on the wheels is not enough to meet the braking force required by the front axle, additional braking force is provided through the hydraulic braking force of the front wheels; the required braking force on the front and rear shafts is formed as follows:
(3) When the strength of brakingzSatisfy the requirement of
In the above-mentioned order, wherein,z C =0.65, the required braking force distribution on the front and rear axles is as follows:
if the electric braking force on the wheel is enough to meet the braking force demand of the front axle, the braking force demand on the front axle and the rear axle is formed as follows:
if the electric braking power on the wheels is not enough to meet the braking force required by the front axle, additional braking force is provided by the hydraulic braking power on the front wheel; the required braking force on the front and rear axles is constituted as follows:
(4) When the strength of brakingzSatisfy the requirements of
In whichz D =1, the required braking force distribution on the front and rear axles is as follows:
wherein the content of the first and second substances,
indicating road surfaceThe coefficient of adhesion;
if the electric braking force on the wheel is enough to meet the braking force demand of the front axle, the braking force demand on the front axle and the rear axle is formed as follows:
if the electric braking power on the wheels is not enough to meet the braking force required by the front axle, additional braking force is provided by the hydraulic braking power on the front wheel; the required braking force on the front and rear axles is constituted as follows:
(5) When in use
When the vehicle is in an emergency braking state, in order to ensure the stability of the vehicle in the braking process, the motor does not participate in braking in the emergency braking state, namely the front wheel braking force is provided by the front wheel hydraulic braking force, and the required braking forces on the front shaft and the rear shaft are distributed according to the following formula:
the required braking force on the front and rear axles is constituted as follows:
2. the method for selecting an operating point of a motor under regenerative braking and formulating a shift schedule as claimed in claim 1, wherein in S2, the selection of the operating point of the motor during shifting is divided into the following three cases:
case 1: when the electric braking power on the wheels before and after shifting is larger than or equal to the required braking power, namely the electric braking power reserve value on the front wheel of shifting
And a brake braking power reserve value on the rear wheels of the gear shift>
Are all greater than the required braking power>
(ii) a The power value of the working point of the motor is->
When the equal power line is moved to a rotating speed value of->
A corresponding position;
case 2: when the electric braking power on the wheels before and after shifting is less than the required braking power, namely the electric braking power reserve value on the front wheel of shifting
And a brake braking power reserve value on the rear wheels of the gear shift>
Are all less than the required braking power>
(ii) a The working point of the motor is firstly along the power value->
The equal power line is moved to a rotating speed value of->
Corresponding to the position, and then the rotating speed value is->
When the equal rotating speed line moves to the brake power reserve value on the rear gear of the gear shifting
The position of (a);
case 3: when the electric braking power on the front gear is less than the required braking force and the electric braking power on the rear gear is more than or equal to the required braking force, namely the electric braking power reserve value on the front gear is
Less than the required braking power>
The brake power reserve value on the rear wheel of the gear shift is pick-up>
Greater than or equal to the braking power required>
(ii) a The working point of the motor firstly has the following power value
The equal power line is moved to a rotating speed value of->
Corresponding position, then along the rotation speed value of
Is moved to the required braking power>
The position of (a);
in the case of the cases 1-3,
indicates that shift is pre-engaged>
Indicates after a gear shift, is engaged>
The rotating speed of the motor in the high-efficiency interval after gear shifting.
3. The method for selecting the operating point of the motor and establishing the gear shifting schedule under the regenerative braking according to claim 1, wherein in step S3, the specific steps for determining the gear shifting schedule in the energy recovery process are as follows:
s3-1: when the vehicle controller identifies that the driver needs to brake, the vehicle state parameters before gear shifting are obtained, including the current vehicle speed
Current brake strength>
The current vehicle gear->
Before shifting gear the battery recovers power>
State of charge of the battery>
(ii) a Judges the current vehicle speed->
If the value is 0, returning to S3-1 if the value is 0; if the current vehicle speed is greater or less>
If not, the current battery state of charge is continuously judged>
Whether or not it is greater than or equal to the maximum value of the state of charge of the battery>
If, ifCurrent Battery State of Charge>
Greater than or equal to the maximum value of the charge state of the battery>
Returning to S3-1; if the current battery state of charge->
Less than maximum battery state of charge->
Then continuously judging the current braking strength->
If it is 0, if the current brake strength->
If the value is 0, returning to S3-1; if the current brake strength->
If not, continuing to execute S3-2; wherein the subscript->
Indicating that the current cycle is the first
Performing secondary circulation;
s3-2: the gear shifting rule is restrained based on the motor speed: calculating a current gear based on a transmission ratio
Change to the other gears>
Corresponding motor speed->
(ii) a According to the motor speed->
Obtaining the corresponding maximum motor power
(ii) a Determination of the requested braking power ^ of the vehicle from the requested braking force>
Judgment is made>
Whether or not it is less than or equal to the maximum motor speed>
(ii) a If yes, jumping to S3-3; otherwise, no shift is performed, and the shift is asserted>
And returning to S3-1;
s3-3: the gear shifting rule is constrained based on the selection strategy of the motor working point of S2;
s3-4: obtaining gears according to constraint conditions
The corresponding motor recovery power->
(ii) a Motor recovered power->
Equal to the braking demand power of the wheel on motor>
And maximum motor power>
In, wherein, in>
In the formula (II)>
For the motor speed after the gear shift, ->
For the motor speed after shifting>
Lower maximum motor torque;
s3-5: distributing electric braking power and hydraulic braking force on the wheels based on the comprehensive braking force distribution strategy of S1:
brake power reserve on wheels if before gear shift
And on-wheel brake power reserve after gear shifting
Are all greater than or equal to the braking power required by the vehicle>
The braking force of the motor on the wheel and the hydraulic braking force are distributed according to the condition that the braking force of the motor on the wheel in the S1 can meet the required braking force;
brake power reserve on wheels if before gear shift
Or on-wheel brake power reserve after gear shifting
Less than the braking power demanded by the vehicle>
If the power of the electric wheel brake and the hydraulic braking force are not enough to meet the requirement of braking force in the S1, distributing the power of the electric wheel brake and the hydraulic braking force;
s3-6: according to the current gear in S3-2
Motor speed of each gear shift outside->
And motor torque->
Obtaining the current gear>
Braking efficiency of motor on each gear wheel outside>
And the recovery power of each battery is->
；
S3-7: the gear shifting rule is restrained based on the recovered power of the battery: selecting the current gear
Battery recovery power of other gears>
Is greater than or equal to>
And recovering power from the pre-shift battery
Make a comparison if->
Greater than or equal to>
Jump to S3-8, otherwise make ^ er>
And returning to S3-1;
s3-8: shifting gears with a target gear of
A corresponding gear; after the gear shifting is finished, the control returns to S3-1 and enables ^ to be selected>
The number of shifts is accumulated.
4. The method for selecting the operating point and making the shift schedule of the motor under the regenerative braking according to claim 3, wherein the constraint conditions in S3 are specifically: if the current maximum motor power
Greater than the required braking power of the vehicle
The power value of the working point of the motor is pick>
When the equal power line is moved to a rotating speed value of->
A corresponding position; otherwise, a switched brake power reserve value is detected on the wheel after the gear shift>
And the required braking power of the vehicle->
If is greater or greater>
＞P B Then the working point of the motor is along the power value->
The equal power line is moved to a rotating speed value of->
Corresponding to the position, and then the rotating speed value is->
The corresponding speed line is moved to the required braking power ≥ of the vehicle>
(ii) a If/or>
</>
If the motor operating point is greater than or equal to the power value>
The equal power line is moved to a rotating speed value of->
Corresponding to the position, and then the rotating speed value is->
Corresponding speed line shift to wheel on-motor braking power reserve value>
。
5. The method for selecting the operating point of the motor and establishing the gear shifting rule under the regenerative braking according to claim 1, further comprising, in step S4, creating an optimal gear distribution map based on the gear shifting rule established in step S3:
and according to the gear shifting rule formulated in the S3, setting the opening degree of a brake pedal from 100% to 0% by taking the vehicle speed of 200km/h as an initial speed, traversing gears corresponding to the maximum battery recovery power under different vehicle speeds and brake pedal opening degrees, namely the optimal gears, and further obtaining an optimal gear distribution map under different vehicle speeds and brake pedal opening degrees based on economy.
6. The method for selecting the operating point of the motor and generating the shift schedule under the regenerative braking according to claim 5, wherein when the optimal gear distribution map is generated, the step length of the vehicle speed is set to be 1km/h, and the step length of the opening degree of the brake pedal is set to be 1%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310046380.1A CN115805816B (en) | 2023-01-31 | 2023-01-31 | Motor working point selection and gear shifting rule making method under regenerative braking |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310046380.1A CN115805816B (en) | 2023-01-31 | 2023-01-31 | Motor working point selection and gear shifting rule making method under regenerative braking |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115805816A CN115805816A (en) | 2023-03-17 |
| CN115805816B true CN115805816B (en) | 2023-04-18 |
Family
ID=85487661
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310046380.1A Active CN115805816B (en) | 2023-01-31 | 2023-01-31 | Motor working point selection and gear shifting rule making method under regenerative braking |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115805816B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116044985B (en) * | 2023-03-30 | 2023-06-02 | 北京航空航天大学 | Cooperative control method for gear shifting process under regenerative braking of automobile |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6116368A (en) * | 1997-11-21 | 2000-09-12 | Lockheed Martin Corp. | Electric vehicle with battery regeneration dependent on battery charge state |
| FR2902945B1 (en) * | 2006-06-27 | 2008-09-12 | Valeo Equip Electr Moteur | METHOD FOR RECOVERING ELECTRIC ENERGY IN A RECUPERATIVE BRAKE VEHICLE |
| FR2966115B1 (en) * | 2010-10-19 | 2012-10-26 | Renault Sa | METHOD AND SYSTEM FOR BRAKING A MOTOR VEHICLE WITH ELECTRICAL OR HYBRID TRACTION |
| CN110667395B (en) * | 2019-09-30 | 2021-03-19 | 重庆大学 | Multi-target optimization method for gear shifting rule of pure electric vehicle of two-gear automatic gearbox based on braking working condition |
| CN112026743B (en) * | 2020-08-28 | 2021-10-12 | 重庆长安汽车股份有限公司 | Energy management method and device for series hybrid electric vehicle and hybrid electric vehicle |
-
2023
- 2023-01-31 CN CN202310046380.1A patent/CN115805816B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN115805816A (en) | 2023-03-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110667395B (en) | Multi-target optimization method for gear shifting rule of pure electric vehicle of two-gear automatic gearbox based on braking working condition | |
| US7216943B2 (en) | Hybrid vehicle | |
| CN103738199B (en) | Two grades of driving control systems of bi-motor and driving control method thereof | |
| EP2447578B1 (en) | Automatic transmission | |
| CN108515970A (en) | Hybrid vehicle | |
| CN105128855B (en) | A kind of control method of twin shaft parallel hybrid power city bus | |
| CN109760682B (en) | Pure electric vehicle climbing torque estimation method, control method and system | |
| CN115805816B (en) | Motor working point selection and gear shifting rule making method under regenerative braking | |
| CN109240125B (en) | Method for calculating two-shaft required torque of gearbox of hybrid vehicle | |
| CN106891899B (en) | Pure electric automobile two-shift automatic variable speed case Best Economy shift schedule calculation method | |
| CN106427985A (en) | Method for in-cylinder brake control applied to hybrid power vehicle type | |
| CN114312330B (en) | Electric automobile braking gear shifting control method and system | |
| CN110667564B (en) | Intelligent management method for autonomous queue running energy of parallel hybrid electric vehicle | |
| CN110873180B (en) | Synchronous gear shifting and speed changing method for two-gear gearbox of hub motor | |
| CN103370220A (en) | Control apparatus for vehicle | |
| CN108177649A (en) | The shifting method and device of a kind of hybrid vehicle | |
| CN106994904A (en) | Energy-recuperation system and method for a kind of electric automobile based on brake-by-wire | |
| CN115489498A (en) | Control method and control device for engineering vehicle, processor and engineering vehicle | |
| Sciarretta et al. | Fundamentals of vehicle modeling | |
| CN115257391A (en) | Three-motor electric automobile composite braking control method, device, equipment and medium | |
| CN105922987A (en) | Gear-down strategy applied in regenerative braking process of hybrid electric vehicle (HEV)/electric vehicle (EV) and electromechanical system | |
| CN112977075A (en) | Brake control method and device for front wheel drive vehicle and automobile | |
| Li et al. | Regenerative Braking Control with Gear Downshifting for Energy Efficiency and Motion Stability Improvement of an Electrical-four-wheel-drive Hybrid Vehicle | |
| CN117141250B (en) | Downhill vehicle speed control method and system and vehicle | |
| CN111791875B (en) | Electromechanical coupling double-clutch hybrid power system driving mode control system and method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |