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CN115805816B - Selection of motor operating point and formulation of shift schedule under regenerative braking - Google Patents

Selection of motor operating point and formulation of shift schedule under regenerative braking Download PDF

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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
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braking
force
braking force
shifting
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CN115805816A (en
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董鹏
李俊青
徐向阳
王书翰
刘艳芳
郭伟
吴思豪
盛家东
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Beihang University
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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

再生制动下电机工作点选择及换挡规律制定方法Motor operating point selection and shifting schedule formulation method under regenerative braking

技术领域Technical Field

本发明涉及纯电动汽车和混合动力汽车控制领域，具体公开了一种再生制动下电机工作点选择及换挡规律制定方法。The invention relates to the field of pure electric vehicle and hybrid electric vehicle control, and specifically discloses a method for selecting a motor working point and formulating a shifting rule under regenerative braking.

背景技术Background Art

为了应对全球能源危机和环境污染，汽车动力总成逐步电动化，其中，以纯电动汽车/混合动力汽车（EV/HEV）为主要代表的新能源汽车快速发展。纯电动汽车/混合动力汽车（EV/HEV）在减少燃油消耗和降低污染排放等方面有巨大的潜能，是当今汽车行业的焦点。制动能量回收是纯电动汽车/混合动力汽车（EV/HEV）实现节能的主要方式，因此提高制动回收的能量、保证制动过程的安全性等问题格外受到关注。In order to cope with the global energy crisis and environmental pollution, the automotive powertrain is gradually electrified, among which new energy vehicles represented by pure electric vehicles/hybrid electric vehicles (EV/HEV) are developing rapidly. Pure electric vehicles/hybrid electric vehicles (EV/HEV) have great potential in reducing fuel consumption and reducing pollution emissions, and are the focus of today's automotive industry. Braking energy recovery is the main way for pure electric vehicles/hybrid electric vehicles (EV/HEV) to achieve energy saving, so issues such as increasing the energy recovered by braking and ensuring the safety of the braking process have received special attention.

在能量回收过程中只是单一研究制动能量回收系统，不将其他系统与制动能量回收系统进行耦合，无法最大幅度提升纯电动汽车/混合动力汽车（EV/HEV）的续驶里程。目前，对于匹配自动变速箱的纯电动汽车/混合动力汽车（EV/HEV），在能量回收的过程中，针对制动力进行分配时，没有涉及到轮端制动与电机制动在换挡规律下的分配。在制动过程中进行换挡，不仅能强化汽车的再加速能力，而且还能提高制动能量回收的能力。因此，需要设计一种能量回收过程中的换挡规律制定方法来保证能量回收率和再加速能力。In the process of energy recovery, only the braking energy recovery system is studied, and other systems are not coupled with the braking energy recovery system, which cannot maximize the range of pure electric vehicles/hybrid electric vehicles (EV/HEV). At present, for pure electric vehicles/hybrid electric vehicles (EV/HEV) equipped with automatic transmissions, when distributing the braking force during energy recovery, the distribution of wheel-end braking and motor braking under the shifting law is not involved. Shifting gears during the braking process can not only enhance the re-acceleration ability of the vehicle, but also improve the ability of braking energy recovery. Therefore, it is necessary to design a method for formulating the shifting law during the energy recovery process to ensure the energy recovery rate and re-acceleration ability.

例如，中国发明专利CN105922987B公开了一种HEV/EV再生制动过程中的降挡策略，确定车速为零或制动踏板开度为零不成立，及电池荷电状态小于电池荷电上限阈值时，根据制动踏板开度得期望制动强度；期望制动强度小于制动强度阈值或当前挡位为1挡不成立时，算当前挡位下驱动电机提供的最大制动力；并根据最大制动力及需求制动力中的较小值，确定驱动电机输出转矩；根据该转矩算当前挡位下电池荷电状态的增加速率；取当前挡位及比其低的挡位对应的电池荷电状态的增加速率中的最大值，与当前挡位的电池荷电状态的增加速率作比较；若前者小，将挡位换到最大值对应的挡位。该发明能提高汽车再加速能力及再生制动回收的能量，从而提升汽车动力性和燃油经济性。但是，该发明未涉及根据轮上电机制动力是否满足需求制动力，分情况制定车辆在制动过程中的电液（电机与液压）制动力的分配，也未实现电机工作点的选取；更不涉及对轮上电机制动力在整个制动过程中所提供的制动力时，对当前挡位下的轮上电机制动力与需求制动力进行对比，以及换挡后的轮上电机制动力与需求制动力的对比。因此，该发明专利不能有效保证能量回收率。For example, Chinese invention patent CN105922987B discloses a downshift strategy during HEV/EV regenerative braking. When the vehicle speed is zero or the brake pedal opening is zero, and the battery state of charge is less than the upper limit threshold of the battery charge, the expected braking strength is obtained according to the brake pedal opening; when the expected braking strength is less than the braking strength threshold or the current gear is 1, the maximum braking force provided by the drive motor in the current gear is calculated; and the output torque of the drive motor is determined according to the smaller value of the maximum braking force and the required braking force; the rate of increase of the battery state of charge in the current gear is calculated according to the torque; the maximum value of the rate of increase of the battery state of charge corresponding to the current gear and the gear lower than it is taken, and compared with the rate of increase of the battery state of charge in the current gear; if the former is smaller, the gear is changed to the gear corresponding to the maximum value. This invention can improve the re-acceleration ability of the vehicle and the energy recovered by regenerative braking, thereby improving the vehicle's power and fuel economy. However, the invention does not involve the allocation of the electro-hydraulic (motor and hydraulic) braking force of the vehicle during the braking process according to whether the on-wheel electric machine force meets the required braking force, nor does it realize the selection of the motor working point; it also does not involve the comparison of the on-wheel electric machine force in the current gear with the required braking force when the on-wheel electric machine force provides the braking force during the entire braking process, and the comparison of the on-wheel electric machine force after the gear shift with the required braking force. Therefore, the invention patent cannot effectively guarantee the energy recovery rate.

此外，在大部分制动工况下，经短暂制动后驾驶员往往有加速需求，那么当车辆从高速制动到低速，变速器的挡位依然保持在高挡位时，此时踩下制动踏板，即使变速器立刻降挡也会产生车辆加速动力延迟的现象。基于以上所讨论的情况，现有技术不能综合考虑轮端制动与电机制动协调控制换挡规律制定方法，无法提高车辆制动后的再加速能力和有效增加能量回收量。In addition, in most braking conditions, the driver often needs to accelerate after a short braking. Then, when the vehicle brakes from high speed to low speed and the gear of the transmission remains in high gear, stepping on the brake pedal at this time will cause a delay in the acceleration power of the vehicle even if the transmission immediately downshifts. Based on the above discussion, the existing technology cannot comprehensively consider the method of formulating the shifting rules for coordinated control of wheel-end braking and motor braking, and cannot improve the re-acceleration ability of the vehicle after braking and effectively increase the amount of energy recovery.

发明内容Summary of the invention

本发明的目的是针对上述现有技术对应的不足，针对前驱车辆，提供一种再生制动下电机工作点选择及换挡规律制定方法，该方法可以有效增加能量回收量，提高了制动后的再加速能力，且保证了制动过程的舒适性。The purpose of the present invention is to address the deficiencies of the above-mentioned prior art and to provide a method for selecting a motor operating point and formulating a shifting schedule under regenerative braking for front-wheel drive vehicles. The method can effectively increase the amount of energy recovery, improve the re-acceleration capability after braking, and ensure the comfort of the braking process.

本发明的技术方案具体如下：The technical solution of the present invention is specifically as follows:

再生制动下电机工作点选择及换挡规律制定方法，适用于前驱车辆，即轮上电机制动力仅作用于车轮前轴的车辆；具体包括如下步骤：The method for selecting the working point of the motor and formulating the shifting rule under regenerative braking is applicable to front-wheel drive vehicles, that is, vehicles in which the power of the on-wheel motor acts only on the front axle of the wheel; specifically, the following steps are included:

S1、制定综合制动力分配策略S1. Formulate a comprehensive braking force distribution strategy

基于轮上电机制动力是否能够满足需求制动力的判断条件，对轮上电机制动力与液压制动力的分配进行协调控制：一是轮上电机制动力能够满足需求制动力，则不需要液压制动力；二是轮上电机制动力不足以满足需求制动力，不足的部分由液压制动力来补充；Based on the judgment condition of whether the wheel electric machine force can meet the required braking force, the distribution of the wheel electric machine force and the hydraulic braking force is coordinated and controlled: first, if the wheel electric machine force can meet the required braking force, then hydraulic braking force is not needed; second, if the wheel electric machine force is not enough to meet the required braking force, the insufficient part is supplemented by hydraulic braking force;

S2、换挡时电机工作点的选择策略S2, Motor operating point selection strategy during gear shifting

根据S1中的两种情形，对电机工作点进行如下选择：一是轮上电机制动力能够满足需求制动力，通过换挡将电机工作点沿着等功率曲线移动至等功率高效率区间，此时轮上电机制动力不变；二是轮上电机制动力不足以满足需求制动力，通过换挡将电机工作点转移至电机高功率区间，此时轮上电机制动力发生变化；According to the two situations in S1, the motor working point is selected as follows: one is that the wheel motor force can meet the required braking force, and the motor working point is moved to the equal power high efficiency interval along the equal power curve by shifting gears, and the wheel motor force remains unchanged; the other is that the wheel motor force is not enough to meet the required braking force, and the motor working point is transferred to the motor high power interval by shifting gears, and the wheel motor force changes;

S3、确定能量回收过程中换挡规律，并执行换挡S3: Determine the shifting rules during energy recovery and execute the shifting

将S2中制定的选择策略作为换挡规律制定的约束条件之一，即换挡前后最大轮上电机制动力和需求制动力对换挡时电机工作点选择的约束；此外，约束条件还包括电机转速和电池回收功率；然后基于约束条件，制定基于经济性的能量回收过程中换挡规律并结合驾驶过程中的实际情况进行换挡。The selection strategy formulated in S2 is used as one of the constraints for the formulation of the shifting schedule, that is, the maximum wheel motor force and required braking force before and after the shifting constrain the selection of the motor operating point during the shifting; in addition, the constraints also include the motor speed and the battery recovery power; then, based on the constraints, a shifting schedule based on the economic energy recovery process is formulated and the shifting is performed in combination with the actual situation during driving.

进一步的，在S1中，对轮上电机制动力与液压制动力的分配进行协调控制，根据不同制动工况下的制动强度的大小，分为以下五种情形：Furthermore, in S1, the distribution of the electric motor force and the hydraulic braking force on the wheel is coordinated and controlled, and is divided into the following five situations according to the magnitude of the braking intensity under different braking conditions:

（1）在轻度制动时，制动强度z满足条件0≤z<z A 时，仅在前轴上提供制动力，z表示制动强度，根据制动踏板开度确定，数值在0-1之间；z A 表示轻度制动时最低制动强度的门限值，前后轴需求制动力按照下式确定：(1) During light braking, when the braking intensity z satisfies the condition 0≤ z < zA , braking force is provided only on the front axle . z represents the braking intensity, which is determined by the brake pedal opening and has a value between 0 and 1. zA represents the threshold value of the minimum braking intensity during light braking. The required braking force of the front and rear axles is determined according to the following formula:

Figure SMS_1
Figure SMS_1

其中，z A 通过下式求得：Among them, z A is obtained by the following formula:

Figure SMS_2
Figure SMS_2

式中，F Brake,Front 和F Brake,Rear 分别表示前轴和后轴的需求制动力，m为车辆质量，L a 和L b 分别表示车辆质心到前轴和后轴的距离，g表示重力加速度，h g 表示车辆质心高度；Where, F Brake,Front and F Brake,Rear represent the required braking forces of the front axle and rear axle respectively, m is the vehicle mass, La and Lb represent the distances from the vehicle center of mass to the front axle and rear axle respectively, g represents the acceleration of gravity, and hg represents the height of the vehicle center of mass;

若轮上电机制动力足以满足前轴需求制动力，前后轴上的需求制动力构成如下式：If the wheel motor force is sufficient to meet the required braking force on the front axle, the required braking force on the front and rear axles is formed as follows:

Figure SMS_3
Figure SMS_3

式中，F MotorBrake 表示轮上电机制动力，F HydraulicBrake,Front 表示前轮液压制动力，F HydraulicBrake,Rear 表示后轮液压制动力；Where, F MotorBrake represents the motor force on the wheel, F HydraulicBrake,Front represents the hydraulic braking force of the front wheel, and F HydraulicBrake,Rear represents the hydraulic braking force of the rear wheel;

若轮上电机制动力不足以满足前轴需求制动力，则通过前轮液压制动力提供额外的制动力；前后轴上的需求制动力构成如下式：If the electric motor force on the wheel is not enough to meet the required braking force on the front axle, the front wheel hydraulic braking force will provide additional braking force; the required braking force on the front and rear axles is composed of the following formula:

Figure SMS_4
Figure SMS_4

（2）当制动强度z满足z A ≤z<z B 时，其中z B =0.5，前后轴需求制动力分配如下：(2) When the braking intensity z satisfies z A ≤ z < z B , where z B = 0.5, the required braking force distribution of the front and rear axles is as follows:

Figure SMS_5
Figure SMS_5

式中，k b =0.99表示制动力分配安全系数；In the formula, k b =0.99 represents the braking force distribution safety factor;

若轮上电机制动力足以满足前轴需求制动力，前后轴上的需要制动力构成如下式：If the wheel motor force is sufficient to meet the required braking force on the front axle, the required braking force on the front and rear axles is formed as follows:

Figure SMS_6
Figure SMS_6

若轮上电机制动力不足以满足前轴需求制动力，则通过前轮液压制动力提供额外的制动力；其前后轴上的需求制动力构成如下式：If the electric motor force on the wheel is not enough to meet the required braking force of the front axle, the additional braking force is provided by the front wheel hydraulic braking force; the required braking force on the front and rear axles is composed of the following formula:

Figure SMS_7
；
Figure SMS_7
;

（3）当制动强度z满足z B ≤z<z C 时，其中，z C =0.65，前后轴上的需求制动力分配如下式：(3) When the braking intensity z satisfies z B ≤ z < z C , where z C = 0.65, the required braking force distribution on the front and rear axles is as follows:

Figure SMS_8
Figure SMS_8

若轮上电机制动力足以满足前轴需求制动力，前后轴上的需求制动力构成如下式：If the wheel motor force is sufficient to meet the required braking force on the front axle, the required braking force on the front and rear axles is formed as follows:

Figure SMS_9
Figure SMS_9

若轮上电机制动力不足以满足前轴需求制动力，则通过前轮轮上液压制动力提供额外的制动力；前后轴上的需求制动力构成如下式：If the on-wheel electric brake force is insufficient to meet the required braking force on the front axle, the additional braking force is provided by the hydraulic brake force on the front wheels; the required braking force on the front and rear axles is formed as follows:

Figure SMS_10
；
Figure SMS_10
;

（4）当制动强度z满足z C ≤z<z D 时，其中z D =1，前后轴上的需求制动力分配如下式：(4) When the braking intensity z satisfies z C ≤ z < z D , where z D = 1, the required braking force distribution on the front and rear axles is as follows:

Figure SMS_11
Figure SMS_11

其中，

Figure SMS_12
表示路面附着系数；in,
Figure SMS_12
It represents the road adhesion coefficient;

若轮上电机制动力足以满足前轴需求制动力，前后轴上的需求制动力构成如下式：If the wheel motor force is sufficient to meet the required braking force on the front axle, the required braking force on the front and rear axles is formed as follows:

Figure SMS_13
Figure SMS_13

若轮上电机制动力不足以满足前轴需求制动力，则通过前轮轮上液压制动力提供额外的制动力；前后轴上的需求制动力构成如下式：If the on-wheel electric brake force is insufficient to meet the required braking force on the front axle, the additional braking force is provided by the hydraulic brake force on the front wheels; the required braking force on the front and rear axles is formed as follows:

Figure SMS_14
；
Figure SMS_14
;

（5）当z≥z D 时，全液压制动，车辆处于紧急制动状态，为保证车辆在制动过程中的稳定性，在紧急制动状态下电机不参与制动，即前轮制动力全部由前轮液压制动力提供，前后轴上的需求制动力按如下公式分配：(5) When z ≥ z D , full hydraulic braking is performed and the vehicle is in emergency braking state. To ensure the stability of the vehicle during braking, the motor does not participate in braking in the emergency braking state, that is, the front wheel braking force is entirely provided by the front wheel hydraulic braking force. The required braking force on the front and rear axles is distributed according to the following formula:

Figure SMS_15
；
Figure SMS_15
;

前后轴上的需求制动力构成如下式：The required braking force on the front and rear axles is formed as follows:

Figure SMS_16
。
Figure SMS_16
.

进一步的，在S2中，换挡时对电机工作点的选择分以下三种情形：Furthermore, in S2, the selection of the motor operating point during gear shifting is divided into the following three situations:

情形1：换挡前、后的轮上电机制动力≥需求制动力时，即换挡前轮上电机制动功率储备值

Figure SMS_17
和换挡后轮上电机制动功率储备值
Figure SMS_18
均大于需求制动功率
Figure SMS_19
；电机工作点沿功率值为
Figure SMS_20
的等功率线移动至转速值为
Figure SMS_21
对应位置；Case 1: When the electric motor braking force on the wheels before and after the gear shift is greater than the required braking force, that is, the electric motor braking power reserve value on the wheels before the gear shift
Figure SMS_17
And the motor braking power reserve value on the rear wheel after shifting
Figure SMS_18
Both are greater than the required braking power
Figure SMS_19
; The power value of the motor working point is
Figure SMS_20
The equal power line moves to the speed value of
Figure SMS_21
Corresponding position;

情形2：换挡前、后的轮上电机制动力＜需求制动力时，即换挡前轮上电机制动功率储备值

Figure SMS_22
和换挡后轮上电机制动功率储备值
Figure SMS_23
均小于需求制动功率
Figure SMS_24
；电机工作点首先沿功率值为
Figure SMS_25
的等功率线移动至转速值为
Figure SMS_26
对应位置，再沿转速值为
Figure SMS_27
的等转速线移动至换挡后轮上电机制动功率储备值
Figure SMS_28
的位置；Case 2: When the electric motor braking force on the wheels before and after the gear shift is less than the required braking force, that is, the motor braking power reserve value on the wheels before the gear shift
Figure SMS_22
And the motor braking power reserve value on the rear wheel after shifting
Figure SMS_23
Both are less than the required braking power
Figure SMS_24
; The motor working point first moves along the power value
Figure SMS_25
The equal power line moves to the speed value of
Figure SMS_26
Corresponding position, then along the speed value
Figure SMS_27
The constant speed line moves to the motor braking power reserve value on the rear wheel after shifting
Figure SMS_28
location;

情形3：换挡前轮上电机制动力＜需求制动力，换挡后的轮上电机制动力≥需求制动力时，即换挡前轮上电机制动功率储备值

Figure SMS_30
小于需求制动功率
Figure SMS_32
，换挡后轮上电机制动功率储备值
Figure SMS_34
大于等于需求制动功率
Figure SMS_31
；电机工作点首先沿功率值为
Figure SMS_33
的等功率线移动至转速值为
Figure SMS_35
对应的位置，再沿转速值为
Figure SMS_36
的等转速线移动至需求制动功率
Figure SMS_29
的位置；Case 3: When the electric motor force on the wheel before shifting is less than the required braking force, and the electric motor force on the wheel after shifting is greater than the required braking force, that is, the motor braking power reserve value on the wheel before shifting
Figure SMS_30
Less than required braking power
Figure SMS_32
, after shifting, the motor braking power reserve value on the wheel
Figure SMS_34
Greater than or equal to the required braking power
Figure SMS_31
; The motor working point first moves along the power value
Figure SMS_33
The equal power line moves to the speed value of
Figure SMS_35
The corresponding position, and then along the speed value
Figure SMS_36
The constant speed line moves to the required braking power
Figure SMS_29
location;

情形1-3中，

Figure SMS_37
表示换挡前，
Figure SMS_38
表示换挡后，
Figure SMS_39
为换挡后电机处于高效率区间下的转速。In situations 1-3,
Figure SMS_37
Indicates before shifting gears,
Figure SMS_38
Indicates that after shifting gears,
Figure SMS_39
It is the speed at which the motor is in the high efficiency range after shifting.

进一步的，在S3中，确定能量回收过程中换挡规律的具体步骤如下：Furthermore, in S3, the specific steps of determining the shifting rule during the energy recovery process are as follows:

S3-1：当车辆控制器识别到驾驶员需要制动时，获取换挡前车辆状态参数，包括当前车速

Figure SMS_48
，当前制动强度
Figure SMS_46
，当前车辆挡位
Figure SMS_54
，换挡前电池回收功率
Figure SMS_43
，电池荷电状态
Figure SMS_57
；判断当前车速
Figure SMS_42
是否为0，若为0，则返回S3-1；若当前车速
Figure SMS_50
不为0，则继续判断当前电池荷电状态
Figure SMS_44
是否大于等于电池荷电状态最大值
Figure SMS_55
，若当前电池荷电状态
Figure SMS_40
大于等于电池荷电状态最大值
Figure SMS_51
，则返回S3-1；若当前电池荷电状态
Figure SMS_49
小于电池荷电状态最大值
Figure SMS_56
，则继续判断当前制动强度
Figure SMS_45
是否为0，若当前制动强度
Figure SMS_52
为0，则返回S3-1；若当前制动强度
Figure SMS_41
不为0，继续执行S3-2；其中，下标
Figure SMS_53
表示当前循环为第
Figure SMS_47
次循环；S3-1: When the vehicle controller recognizes that the driver needs to brake, obtain the vehicle state parameters before shifting, including the current vehicle speed
Figure SMS_48
, current braking intensity
Figure SMS_46
, current vehicle gear
Figure SMS_54
, battery recovery power before shifting
Figure SMS_43
, battery state of charge
Figure SMS_57
; Determine the current vehicle speed
Figure SMS_42
Is it 0? If it is 0, return to S3-1; if the current speed
Figure SMS_50
If it is not 0, continue to judge the current battery charge state
Figure SMS_44
Is it greater than or equal to the maximum value of the battery state of charge?
Figure SMS_55
If the current battery state of charge
Figure SMS_40
Greater than or equal to the maximum battery state of charge
Figure SMS_51
, then return to S3-1; if the current battery charge state
Figure SMS_49
Less than the maximum battery state of charge
Figure SMS_56
, then continue to judge the current braking intensity
Figure SMS_45
Is it 0? If the current braking strength
Figure SMS_52
If the current braking intensity is 0, then return to S3-1;
Figure SMS_41
If it is not 0, continue to execute S3-2;
Figure SMS_53
Indicates that the current cycle is
Figure SMS_47
Secondary cycle;

S3-2：基于电机转速对换挡规律进行约束：基于变速箱速比计算当前挡位

Figure SMS_60
换至其余各挡位
Figure SMS_63
对应的电机转速
Figure SMS_65
；根据电机转速
Figure SMS_59
得到对应最大电机功率
Figure SMS_62
；由需求制动力求得车辆的需求制动功率
Figure SMS_64
，判断
Figure SMS_66
是否小于等于最大电机转速
Figure SMS_58
；若是，则跳转至S3-3；否则，不执行换挡，令
Figure SMS_61
并返回S3-1；S3-2: Constrain the shifting schedule based on the motor speed: Calculate the current gear based on the gearbox ratio
Figure SMS_60
Shift to other gears
Figure SMS_63
Corresponding motor speed
Figure SMS_65
; According to the motor speed
Figure SMS_59
Get the corresponding maximum motor power
Figure SMS_62
; The required braking power of the vehicle is obtained from the required braking force
Figure SMS_64
,judge
Figure SMS_66
Is it less than or equal to the maximum motor speed?
Figure SMS_58
; If yes, jump to S3-3; otherwise, do not execute the gear shift,
Figure SMS_61
And return to S3-1;

S3-3：基于S2的电机工作点的选择策略对换挡规律进行约束；S3-3: constrain the shifting schedule based on the motor operating point selection strategy of S2;

S3-4：根据约束条件，得到挡位

Figure SMS_68
所对应的电机回收功率
Figure SMS_71
；电机回收功率
Figure SMS_74
等于轮上电机制动需求功率
Figure SMS_69
与最大电机功率
Figure SMS_72
中的较小值，其中，
Figure SMS_73
，式中，
Figure SMS_75
为换挡后的电机转速，
Figure SMS_67
为换挡后电机转速
Figure SMS_70
下的最大电机扭矩；S3-4: Get the gear position according to the constraints
Figure SMS_68
Corresponding motor recovery power
Figure SMS_71
; Motor recovery power
Figure SMS_74
Equal to the braking power required by the wheel motor
Figure SMS_69
With maximum motor power
Figure SMS_72
The smaller value of
Figure SMS_73
, where
Figure SMS_75
is the motor speed after shifting,
Figure SMS_67
Motor speed after shifting
Figure SMS_70
Maximum motor torque under ;

S3-5：基于S1的所述综合制动力分配策略，对轮上电机制动力和液压制动力进行分配：S3-5: Based on the comprehensive braking force distribution strategy of S1, the electric motor braking force and the hydraulic braking force on the wheel are distributed:

若换挡前的轮上电机制动功率储备

Figure SMS_76
和换挡后的轮上电机制动功率储备
Figure SMS_77
均大于等于车辆所需求的制动功率
Figure SMS_78
，则轮上电机制动力和液压制动力根据S1中轮上电机制动力能够满足需求制动力的情况进行分配；If the on-wheel motor braking power reserve before shifting
Figure SMS_76
And the on-wheel motor braking power reserve after gear shifting
Figure SMS_77
Both are greater than or equal to the braking power required by the vehicle
Figure SMS_78
, then the wheel motor force and hydraulic braking force are distributed according to whether the wheel motor force in S1 can meet the required braking force;

若换挡前的轮上电机制动功率储备

Figure SMS_79
或换挡后的轮上电机制动功率储备
Figure SMS_80
小于车辆所需求的制动功率
Figure SMS_81
，则轮上电机制动力和液压制动力根据S1中轮上电机制动力不足以满足需求制动力的情况进行分配；If the on-wheel motor braking power reserve before shifting
Figure SMS_79
Or the on-wheel motor braking power reserve after gear shifting
Figure SMS_80
Less than the braking power required by the vehicle
Figure SMS_81
, then the wheel motor force and hydraulic braking force are allocated according to the situation that the wheel motor force in S1 is insufficient to meet the required braking force;

S3-6：根据S3-2中当前挡位

Figure SMS_82
之外各换挡的电机转速
Figure SMS_83
和电机扭矩
Figure SMS_84
，得到当前挡位
Figure SMS_85
之外各挡位轮上电机制动效率
Figure SMS_86
，以及各挡位电池回收功率
Figure SMS_87
；S3-6: According to the current gear position in S3-2
Figure SMS_82
The motor speed of each gear shift
Figure SMS_83
and motor torque
Figure SMS_84
, get the current gear
Figure SMS_85
Other gears on the wheel motor braking efficiency
Figure SMS_86
, and battery recovery power in each gear
Figure SMS_87
;

S3-7：基于电池回收功率对换挡规律进行约束：选取当前挡位

Figure SMS_88
之外各挡位的电池回收功率
Figure SMS_89
中的最大值
Figure SMS_90
，并与换挡前电池回收功率
Figure SMS_91
进行比较，如果
Figure SMS_92
大于
Figure SMS_93
，跳转至S3-8，否则令
Figure SMS_94
，并返回S3-1 ；S3-7: Constrain the shifting schedule based on battery recovery power: Select the current gear
Figure SMS_88
Battery recovery power in all other gears
Figure SMS_89
The maximum value in
Figure SMS_90
and recover power from the battery before shifting
Figure SMS_91
For comparison, if
Figure SMS_92
Greater than
Figure SMS_93
, jump to S3-8, otherwise
Figure SMS_94
, and return to S3-1;

S3-8：进行换挡，目标挡位为

Figure SMS_95
对应的挡位；换挡完成后返回S3-1，并令
Figure SMS_96
，对换挡次数进行累计。S3-8: Shift gears, target gear is
Figure SMS_95
After the gear shift is completed, return to S3-1 and make
Figure SMS_96
, the number of gear shifts is accumulated.

进一步的，在S3中的约束条件具体为：若当前最大电机功率

Figure SMS_103
大于车辆的需求制动功率
Figure SMS_101
，则电机的工作点沿功率值为
Figure SMS_113
的等功率线移动至转速值为
Figure SMS_104
对应位置；否则获取换挡后的轮上电机制动功率储备值
Figure SMS_114
和车辆的需求制动功率
Figure SMS_98
，若
Figure SMS_109
＞
Figure SMS_99
，则电机工作点先沿功率值为
Figure SMS_108
的等功率线移动至转速值为
Figure SMS_97
对应位置，再沿转速值为
Figure SMS_107
对应的转速线移动到车辆的需求制动功率
Figure SMS_102
；若
Figure SMS_111
<
Figure SMS_106
，则电机工作点先沿功率值为
Figure SMS_112
的等功率线移动至转速值为
Figure SMS_105
对应位置，再沿转速值为
Figure SMS_110
对应的转速线移动到轮上电机制动功率储备值
Figure SMS_100
。Furthermore, the constraint condition in S3 is as follows: if the current maximum motor power
Figure SMS_103
Greater than the vehicle's required braking power
Figure SMS_101
, then the motor's operating point along the power value is
Figure SMS_113
The equal power line moves to the speed value of
Figure SMS_104
Corresponding position; otherwise, obtain the on-wheel motor braking power reserve value after gear shifting
Figure SMS_114
and the vehicle's required braking power
Figure SMS_98
,like
Figure SMS_109
＞
Figure SMS_99
, then the power value of the motor working point is
Figure SMS_108
The equal power line moves to the speed value of
Figure SMS_97
Corresponding position, then along the speed value
Figure SMS_107
The corresponding speed line moves to the required braking power of the vehicle
Figure SMS_102
;like
Figure SMS_111
<
Figure SMS_106
, then the power value of the motor working point is
Figure SMS_112
The equal power line moves to the speed value of
Figure SMS_105
Corresponding position, then along the speed value
Figure SMS_110
The corresponding speed line moves to the wheel motor braking power reserve value
Figure SMS_100
.

进一步的，本发明还包括：Furthermore, the present invention also includes:

S4、基于S3制定的换挡规律，制作最优挡位分布图S4: Create an optimal gear distribution map based on the gear shifting rules developed in S3

根据S3中制定的换挡规律，以车速200km/h为初始速度，设置制动踏板开度从100%到0%，遍历出不同车速和制动踏板开度下的最大电池回收功率对应的挡位，即为最优挡位，进而得到基于经济性的不同车速和制动踏板开度下最优挡位分布图。According to the shifting rules formulated in S3, with a vehicle speed of 200 km/h as the initial speed, the brake pedal opening is set from 100% to 0%, and the gear corresponding to the maximum battery recovery power at different vehicle speeds and brake pedal openings is traversed, which is the optimal gear. Then, the optimal gear distribution map at different vehicle speeds and brake pedal openings based on economy is obtained.

进一步的，在制作最优挡位分布图时，设置车速步长为1km/h，制动踏板开度步长为1%。Furthermore, when making the optimal gear distribution map, the vehicle speed step is set to 1 km/h and the brake pedal opening step is set to 1%.

相比于现有技术，本发明的有益效果在于：Compared with the prior art, the present invention has the following beneficial effects:

（1）本发明根据轮上电机制动力是否满足需求制动力，分情况制定了车辆在制动过程中的电液制动力的分配，实现了电机工作点的选取；在探究轮上电机制动力在整个制动过程中所提供的制动力时，不仅对当前挡位下的轮上电机制动力与需求制动力进行了对比，而且还考虑了换挡后的轮上电机制动力与需求制动力的对比。(1) The present invention formulates the distribution of the electro-hydraulic braking force of the vehicle during the braking process according to whether the on-wheel electric motor force meets the required braking force, thereby realizing the selection of the motor working point; when exploring the braking force provided by the on-wheel electric motor force during the entire braking process, not only the on-wheel electric motor force under the current gear position is compared with the required braking force, but also the comparison between the on-wheel electric motor force and the required braking force after the gear shift is considered.

（2）通过制定的液压制动与电机制动协调控制换挡规律方法，提升了车辆能量回收率、提高了车辆再加速能力和提高了驾驶的安全性，且保证了制动过程的舒适性，延长了纯电动汽车/混合动力汽车（EV/HEV）的续驶里程。(2) The developed method of coordinated control of shifting rules by hydraulic braking and electric motor braking has improved the vehicle's energy recovery rate, improved the vehicle's re-acceleration capability, and improved driving safety. It also ensures the comfort of the braking process and extends the driving range of pure electric vehicles/hybrid electric vehicles (EV/HEV).

附图说明BRIEF DESCRIPTION OF THE DRAWINGS

为了更清楚地说明本发明实施例或现有技术中的技术方案，下面将对实施例或现有技术描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本发明中记载的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动性的前提下，还可以根据这些附图获得其他的附图。In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

图1为本发明的综合制动力分配策略图；FIG1 is a diagram of a comprehensive braking force distribution strategy of the present invention;

图2为本发明的能量回收过程步骤1换挡电机工作点选择示意图；FIG2 is a schematic diagram of the selection of the working point of the shift motor in step 1 of the energy recovery process of the present invention;

图3为本发明的能量回收过程步骤2换挡电机工作点选择示意图；FIG3 is a schematic diagram of the selection of the working point of the shift motor in step 2 of the energy recovery process of the present invention;

图4为本发明的能量回收过程步骤3换挡电机工作点选择示意图；FIG4 is a schematic diagram of the selection of the working point of the shift motor in step 3 of the energy recovery process of the present invention;

图5为本发明的能量回收过程换挡工作点选择流程图；FIG5 is a flow chart of selecting a shift operating point during an energy recovery process of the present invention;

图6为本发明的基于经济性的换挡规律流程图；FIG6 is a flow chart of the shifting schedule based on economy of the present invention;

图7为本发明的基于经济性的最优挡位分布图。FIG. 7 is an optimal gear distribution diagram based on economy of the present invention.

具体实施方式DETAILED DESCRIPTION

为使本发明实施例的目的、技术方案和优点更加清楚，下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例是本发明一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域技术人员在没有作出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

一种考虑液压制动与电机制动协调控制的再生制动下电机工作点选择及换挡规律制定方法，该方法共包含四个步骤，分别是综合制动力分配策略、制动能量回收过程电机工作点选择、制动能量回收过程中换挡规律制定和制定经济性的最优挡位分布图并执行换挡。四个步骤之间呈递进关系，以下分别对四个步骤进行详细阐述：A method for selecting the motor working point and formulating the shifting rule under regenerative braking considering the coordinated control of hydraulic braking and motor braking. The method includes four steps, namely, comprehensive braking force distribution strategy, motor working point selection during braking energy recovery, shifting rule formulation during braking energy recovery, and formulating the economic optimal gear distribution map and executing the shifting. The four steps are in a progressive relationship, and the following is a detailed description of the four steps:

1、综合制动力分配策略1. Comprehensive braking force distribution strategy

该制动力分配策略将液压制动与电机制动协调分配根据不同的制动工况下制动强度的大小分为了五种情况，其中前四种情况下电机制动力与液压制动力的分配可以进一步归纳为两种情形：一是轮上电机制动力能够满足需求制动力，二是轮上电机制动力不足以满足需求制动力，不足的部分由前后液压制动力来补充。具体的电液制动力分配如以下所述：This braking force distribution strategy divides the coordinated distribution of hydraulic braking and electric braking into five cases according to the braking intensity under different braking conditions. The distribution of electric braking force and hydraulic braking force in the first four cases can be further summarized into two cases: one is that the electric braking force on the wheel can meet the required braking force, and the other is that the electric braking force on the wheel is not enough to meet the required braking force, and the insufficient part is supplemented by the front and rear hydraulic braking force. The specific electro-hydraulic braking force distribution is as follows:

（1）在轻度制动时，制动强度z满足条件0≤z<z A 时，仅在前轴上提供制动力，z表示制动强度，根据制动踏板开度确定，数值在0-1之间；z A 表示轻度制动时最低制动强度的门限值，前后轴需求制动力按照下式确定：(1) During light braking, when the braking intensity z satisfies the condition 0≤ z < zA , braking force is provided only on the front axle . z represents the braking intensity, which is determined by the brake pedal opening and has a value between 0 and 1. zA represents the threshold value of the minimum braking intensity during light braking. The required braking force of the front and rear axles is determined according to the following formula:

Figure SMS_115
Figure SMS_115

若轮上电机制动力可以满足总需求制动力，前后制动力分配如下式：If the wheel motor force can meet the total required braking force, the front and rear braking force distribution is as follows:

Figure SMS_116
Figure SMS_116

若轮上电机制动力小于总需求制动力时，则通过前轴液压制动力提供额外的制动力。其前后轴上的制动力分配如下式：If the wheel electric motor force is less than the total required braking force, the front axle hydraulic braking force will provide additional braking force. The braking force distribution on the front and rear axles is as follows:

Figure SMS_117
Figure SMS_117

（2）当制动强度满足z A ≤z<z B 时，其中z B =0.5，制动强度较大，为了尽可能多地回收制动能量，同时保证制动过程中的稳定性，前后轴制动力沿ECE法规限制范围下限的曲线进行分配，前后轴需求制动力分配如下：(2) When the braking intensity satisfies z A ≤ z < z B , where z B = 0.5, the braking intensity is relatively large. In order to recover as much braking energy as possible while ensuring stability during braking, the front and rear axle braking forces are distributed along the curve at the lower limit of the ECE regulation limit range. The front and rear axle required braking force distribution is as follows:

Figure SMS_118
Figure SMS_118

式中，k b =0.99表示制动力分配安全系数；In the formula, k b =0.99 represents the braking force distribution safety factor;

若轮上电机制动力可以满足前轴需求制动力，前后轴上的制动力分配如下式：If the wheel motor force can meet the required braking force of the front axle, the braking force distribution on the front and rear axles is as follows:

Figure SMS_119
Figure SMS_119

若轮上电机制动力小于前轴需求制动力时，则通过前轴液压制动力提供额外的制动力。其前后轴上的制动力分配如下式：If the electric motor force on the wheel is less than the required braking force on the front axle, the front axle hydraulic braking force will provide additional braking force. The braking force distribution on the front and rear axles is as follows:

Figure SMS_120
Figure SMS_120

（3）当制动强度足z B ≤z<z C 时，其中，z C =0.65，即图1中的BC段，此时前后需求制动力分配如下：(3) When the braking intensity is z B ≤ z < z C , where z C = 0.65, i.e., segment BC in Figure 1, the front and rear braking force distribution is as follows:

Figure SMS_121
Figure SMS_121

若轮上电机制动力可以满足前轴需求制动力，前后轴上的制动力分配如下式：If the wheel motor force can meet the required braking force of the front axle, the braking force distribution on the front and rear axles is as follows:

Figure SMS_122
Figure SMS_122

若轮上电机制动力小于前轴需求制动力时，则通过前轴液压制动力提供前轴额外的制动力；其前后轴上的制动力分配如下式：If the electric motor force on the wheel is less than the required braking force on the front axle, the front axle hydraulic braking force will provide additional braking force on the front axle; the braking force distribution on the front and rear axles is as follows:

Figure SMS_123
Figure SMS_123

（4）当z C ≤z<z D 时，其中z D =1，即图1中的CD段，沿靠近I曲线法规限制范围下限的CD曲线分配前后轴需求制动力：(4) When z C ≤ z < z D , where z D = 1, i.e., segment CD in Figure 1, the required braking forces of the front and rear axles are distributed along the CD curve close to the lower limit of the regulatory limit range of the I curve:

Figure SMS_124
Figure SMS_124

若轮上电机制动力可以满足前轴需求制动力，前后轴上的制动力分配如下式：If the wheel motor force can meet the required braking force of the front axle, the braking force distribution on the front and rear axles is as follows:

Figure SMS_125
Figure SMS_125

若轮上电机制动力小于前轴需求制动力时，则通过前轴液压制动力提供额外的制动力；其前后轴上的制动力分配如下式：If the electric motor force on the wheel is less than the required braking force on the front axle, the additional braking force is provided by the front axle hydraulic braking force; the braking force distribution on the front and rear axles is as follows:

Figure SMS_126
Figure SMS_126

（5）当z≥zD时，车辆处于紧急制动状态，采取全液压制动。由于电机的瞬态响应速度通常滞后于液压制动系统，在触发制动防抱死系统时难以保证控制精度。为保证车辆在制动过程中的稳定性，在紧急制动状态下电机不参与制动，即前轮制动器制动力全部由机械液压制动器提供。全液压制动时，前后轴上的制动力按如下公式分配：(5) When z ≥ z D , the vehicle is in emergency braking state and full hydraulic braking is adopted. Since the transient response speed of the motor usually lags behind the hydraulic braking system, it is difficult to ensure the control accuracy when the anti-lock braking system is triggered. In order to ensure the stability of the vehicle during braking, the motor does not participate in braking in the emergency braking state, that is, the braking force of the front wheel brake is entirely provided by the mechanical hydraulic brake. In full hydraulic braking, the braking force on the front and rear axles is distributed according to the following formula:

Figure SMS_127
；
Figure SMS_127
;

前后轴上的需求制动力构成如下式：The required braking force on the front and rear axles is formed as follows:

Figure SMS_128
。
Figure SMS_128
.

综上所述，综合制动力分配策略在制动强度较小时采用以轮上电机制动力占比较大的分配方式，有利于提高电机制动功率，提升回收的能量；在制动强度较大时采用理想制动力分配策略，以保证制动稳定性和前后轴制动力分配的平衡。因此，所制定的综合制动力分配策略，能在保证制动稳定性的前提下提升能量回收率。In summary, the comprehensive braking force distribution strategy adopts a distribution method with a larger proportion of on-wheel motor force when the braking intensity is small, which is conducive to improving the motor braking power and increasing the recovered energy; when the braking intensity is large, the ideal braking force distribution strategy is adopted to ensure the balance of braking stability and front and rear axle braking force distribution. Therefore, the formulated comprehensive braking force distribution strategy can improve the energy recovery rate while ensuring braking stability.

2、制动能量回收过程换挡工作点选择2. Selection of gear shifting working point during braking energy recovery process

在综合制动力分配策略中可知，电机制动力与液压制动力的分配有两种情形，一是轮上电机制动力能够满足需求制动力，二是电机制动力不足以满足需求制动力，不足的部分由前后液压制动力来补充。对于第一种情形，通过换挡可以调整电机工作点至等功率高效率区间，以实现能量回收率的提升，此时轮上电机制动力不变。对于第二种情形，通过换挡可以调整电机工作点转移至高功率区间，以实现能量回收率的提升，此时轮上电机制动力发生变化。因此该模块主要是针对综合制动力分配策略下，电机在参与整个制动过程中，其工作点怎么选择的原理。该原理依据换挡前后轮上电机制动力与需求制动力大小的区别，分为三种情况，分别是：换挡前后的轮上电机制动力≥需求制动力；换挡前后的轮上电机制动力＜需求制动力；换挡前轮上电机制动力＜需求制动力，换挡后轮上电机制动力≥需求制动力。根据分析，将其总结为能量回收过程中换挡工作点的选择机理，接下来结合图2、图3、图4和图5对机理进行解释，其中图2-5表示电机的map，对每个车辆都是已知的；可以显示效率，转速，转矩以及功率之间的关系。以某一转速为例，该转速下对应电机不同的扭矩，该转速与该转速下电机不同扭矩相乘，即可得到该转速下对应的电机不同功率；改变不同转速，同样可以获取每个转速下的电机不同功率，把功率相等的点连起来，即为电机的等功率线，如图2-5中所示的等功率曲线，并且在图2-5中的6条等功率曲线中从上到下功率依次增加，具体为最上方的等功率线为10kw，依次往下分别为20kw、30kw、40kw、50kw、60kw。In the comprehensive braking force distribution strategy, it can be seen that there are two situations for the distribution of electric machine force and hydraulic braking force. One is that the electric machine force on the wheel can meet the required braking force, and the other is that the electric machine force is not enough to meet the required braking force, and the insufficient part is supplemented by the front and rear hydraulic braking force. For the first situation, the motor working point can be adjusted to the equal power high efficiency range by shifting gears to achieve the improvement of energy recovery rate. At this time, the electric machine force on the wheel remains unchanged. For the second situation, the motor working point can be adjusted to the high power range by shifting gears to achieve the improvement of energy recovery rate. At this time, the electric machine force on the wheel changes. Therefore, this module is mainly aimed at the principle of how the motor selects its working point during the entire braking process under the comprehensive braking force distribution strategy. This principle is divided into three situations based on the difference between the electric machine force on the wheel before and after the gear shift and the required braking force, namely: the electric machine force on the wheel before and after the gear shift ≥ the required braking force; the electric machine force on the wheel before and after the gear shift < the required braking force; the electric machine force on the wheel before the gear shift < the required braking force, and the electric machine force on the wheel after the gear shift ≥ the required braking force. According to the analysis, it is summarized as the selection mechanism of the shifting working point during the energy recovery process. Next, the mechanism is explained in combination with Figures 2, 3, 4 and 5. Figures 2-5 show the map of the motor, which is known to each vehicle; it can show the relationship between efficiency, speed, torque and power. Take a certain speed as an example. The speed corresponds to different torques of the motor. The speed is multiplied by the different torques of the motor at the speed to get the different powers of the motor corresponding to the speed. By changing different speeds, the different powers of the motor at each speed can also be obtained. Connecting the points with equal power is the equal power line of the motor, as shown in the equal power curve in Figure 2-5. In the 6 equal power curves in Figure 2-5, the power increases from top to bottom. Specifically, the top equal power line is 10kw, and the lower ones are 20kw, 30kw, 40kw, 50kw and 60kw respectively.

换挡时电机工作点的选择分如下三种情形：The selection of the motor operating point during gear shifting is divided into the following three situations:

情形1：换挡前、后的轮上电机制动力≥需求制动力时，即换挡前轮上电机制动功率储备值

Figure SMS_129
和换挡后轮上电机制动功率储备值
Figure SMS_130
均大于需求制动功率
Figure SMS_131
；电机工作点沿功率值为
Figure SMS_132
的等功率线移动至转速值为
Figure SMS_133
对应位置；如图2中ab线所示。Case 1: When the electric motor braking force on the wheels before and after the gear shift is greater than the required braking force, that is, the electric motor braking power reserve value on the wheels before the gear shift
Figure SMS_129
And the motor braking power reserve value on the rear wheel after shifting
Figure SMS_130
Both are greater than the required braking power
Figure SMS_131
; The power value of the motor working point is
Figure SMS_132
The equal power line moves to the speed value of
Figure SMS_133
Corresponding position; as shown by line ab in Figure 2.

情形2：换挡前、后的轮上电机制动力＜需求制动力时，即换挡前轮上电机制动功率储备值

Figure SMS_134
和换挡后轮上电机制动功率储备值
Figure SMS_135
均小于需求制动功率
Figure SMS_136
；电机工作点首先沿功率值为
Figure SMS_137
的等功率线移动至转速值为
Figure SMS_138
对应位置，再沿转速值为
Figure SMS_139
的等转速线移动至换挡后轮上电机制动功率储备值
Figure SMS_140
的位置；如图3中ab和bd线所示。Case 2: When the electric motor braking force on the wheels before and after the gear shift is less than the required braking force, that is, the motor braking power reserve value on the wheels before the gear shift
Figure SMS_134
And the motor braking power reserve value on the rear wheel after shifting
Figure SMS_135
Both are less than the required braking power
Figure SMS_136
; The motor working point first moves along the power value
Figure SMS_137
The equal power line moves to the speed value of
Figure SMS_138
Corresponding position, then along the speed value
Figure SMS_139
The constant speed line moves to the motor braking power reserve value on the rear wheel after shifting
Figure SMS_140
The position of the device is shown as lines ab and bd in Figure 3.

情形3：换挡前轮上电机制动力＜需求制动力，换挡后的轮上电机制动力≥需求制动力时，即换挡前轮上电机制动功率储备值

Figure SMS_142
小于需求制动功率
Figure SMS_144
，换挡后轮上电机制动功率储备值
Figure SMS_146
大于等于需求制动功率
Figure SMS_143
；电机工作点首先沿功率值为
Figure SMS_145
的等功率线移动至转速值为
Figure SMS_147
对应的位置，再沿转速值为
Figure SMS_148
的等转速线移动至需求制动功率
Figure SMS_141
的位置；如图4中ab和bc线所示。Case 3: When the electric motor force on the wheel before shifting is less than the required braking force, and the electric motor force on the wheel after shifting is greater than the required braking force, that is, the motor braking power reserve value on the wheel before shifting
Figure SMS_142
Less than required braking power
Figure SMS_144
, after shifting, the motor braking power reserve value on the wheel
Figure SMS_146
Greater than or equal to the required braking power
Figure SMS_143
; The motor working point first moves along the power value
Figure SMS_145
The equal power line moves to the speed value of
Figure SMS_147
The corresponding position, and then along the speed value
Figure SMS_148
The constant speed line moves to the required braking power
Figure SMS_141
The position of the device is shown as lines ab and bc in FIG4 .

将以上三种情形制作为如图5所示的能量回收过程换挡工作点选择的流程图，通过对车辆运行在不同的制动工况下对电机的相关参数进行约束，以达到目标需求。The above three situations are made into a flowchart of the gear shifting working point selection in the energy recovery process as shown in FIG5 . The target requirements are achieved by constraining the relevant parameters of the motor under different braking conditions of the vehicle.

3、基于经济性能量回收过程中换挡规律的选择3. Selection of shifting rules based on economic energy recovery

能量回收过程换挡工作点的选择共有三种情况，这三种情况的实质是换挡前后最大电机制动功率和需求制动功率对换挡工作点选择的约束。对于换挡规律的制定，首先根据能量回收过程中换挡工作点的选择得出换挡前后最大电机制动功率和需求制动功率对换挡工作点的选择约束条件，对于最大电机制动功率，其约束了换挡工作点的转移，进而影响电机制动功率。对于需求制动功率，其同样约束了换挡工作点的转移，影响了电机制动功率。在满足以上两个约束条件下，换挡后的电机以各个挡位的电池回收功率作为判断条件，遍历各个挡位求得最大电池回收功率及对应的挡位，并基于计算结果进行换挡规律的制定。下面将对基于经济性的换挡规律制定的步骤进行介绍，流程图如图6所示。There are three situations for selecting the shifting working point during the energy recovery process. The essence of these three situations is the constraints on the selection of the shifting working point by the maximum motor braking power and the required braking power before and after the shifting. For the formulation of the shifting rule, firstly, the selection constraints of the maximum motor braking power and the required braking power before and after the shifting working point are obtained according to the selection of the shifting working point during the energy recovery process. For the maximum motor braking power, it constrains the transfer of the shifting working point, thereby affecting the motor braking power. For the required braking power, it also constrains the transfer of the shifting working point, affecting the motor braking power. Under the above two constraints, the motor after the shifting takes the battery recovery power of each gear as the judgment condition, traverses each gear to obtain the maximum battery recovery power and the corresponding gear, and formulates the shifting rule based on the calculation results. The steps for formulating the shifting rule based on economy are introduced below, and the flow chart is shown in Figure 6.

步骤1：当车辆控制器识别到驾驶员需要制动时，获取换挡前车辆状态参数，包括当前车速

Figure SMS_150
，当前制动强度
Figure SMS_154
，当前车辆挡位
Figure SMS_161
，换挡前电池回收功率
Figure SMS_151
，电池荷电状态
Figure SMS_159
；判断当前车速
Figure SMS_155
是否为0，若为0，则返回步骤1；若当前车速
Figure SMS_164
不为0，则继续判断当前电池荷电状态
Figure SMS_156
是否大于等于电池荷电状态最大值
Figure SMS_162
，若当前电池荷电状态
Figure SMS_149
大于等于电池荷电状态最大值
Figure SMS_160
，则返回步骤1；若当前电池荷电状态
Figure SMS_152
小于电池荷电状态最大值
Figure SMS_165
，则继续判断当前制动强度
Figure SMS_158
是否为0，若当前制动强度
Figure SMS_166
为0，则返回步骤1；若当前制动强度
Figure SMS_157
不为0，继续执行步骤2；其中，下标
Figure SMS_163
表示当前循环为第
Figure SMS_153
次循环；Step 1: When the vehicle controller recognizes that the driver needs to brake, it obtains the vehicle state parameters before shifting, including the current vehicle speed
Figure SMS_150
, current braking intensity
Figure SMS_154
, current vehicle gear
Figure SMS_161
, battery recovery power before shifting
Figure SMS_151
, battery state of charge
Figure SMS_159
; Determine the current vehicle speed
Figure SMS_155
Is it 0? If it is 0, return to step 1. If the current speed
Figure SMS_164
If it is not 0, continue to judge the current battery charge state
Figure SMS_156
Is it greater than or equal to the maximum value of the battery state of charge?
Figure SMS_162
If the current battery state of charge
Figure SMS_149
Greater than or equal to the maximum battery state of charge
Figure SMS_160
, then return to step 1; if the current battery charge state
Figure SMS_152
Less than the maximum battery state of charge
Figure SMS_165
, then continue to judge the current braking intensity
Figure SMS_158
Is it 0? If the current braking strength
Figure SMS_166
is 0, then return to step 1; if the current braking intensity
Figure SMS_157
If it is not 0, continue to step 2; where the subscript
Figure SMS_163
Indicates that the current cycle is
Figure SMS_153
Secondary cycle;

步骤2：基于电机转速对换挡规律进行约束：基于变速箱速比计算当前挡位

Figure SMS_168
换至其余各挡位
Figure SMS_170
对应的电机转速
Figure SMS_173
；根据电机转速
Figure SMS_169
得到对应最大电机功率
Figure SMS_172
；由需求制动力求得车辆的需求制动功率
Figure SMS_174
，判断
Figure SMS_175
是否小于等于最大电机转速
Figure SMS_167
；若是，则跳转至步骤3；否则，不执行换挡，令
Figure SMS_171
并返回步骤1。Step 2: Constrain the shift schedule based on the motor speed: Calculate the current gear based on the gearbox ratio
Figure SMS_168
Shift to other gears
Figure SMS_170
Corresponding motor speed
Figure SMS_173
; According to the motor speed
Figure SMS_169
Get the corresponding maximum motor power
Figure SMS_172
; The required braking power of the vehicle is obtained from the required braking force
Figure SMS_174
,judge
Figure SMS_175
Is it less than or equal to the maximum motor speed?
Figure SMS_167
; If yes, jump to step 3; otherwise, do not perform the gear shift, let
Figure SMS_171
And return to step 1.

步骤3：基于电机工作点的选择策略对换挡规律进行约束。Step 3: Constrain the shift schedule based on the motor operating point selection strategy.

步骤4：根据约束条件，得到挡位

Figure SMS_177
所对应的电机回收功率
Figure SMS_181
；电机回收功率
Figure SMS_183
等于轮上电机制动需求功率
Figure SMS_178
与最大电机功率
Figure SMS_180
中的较小值，其中，
Figure SMS_182
，式中，
Figure SMS_184
为换挡后的电机转速，
Figure SMS_176
为换挡后电机转速
Figure SMS_179
下的最大电机扭矩。Step 4: Get the gear position according to the constraints
Figure SMS_177
Corresponding motor recovery power
Figure SMS_181
; Motor recovery power
Figure SMS_183
Equal to the braking power required by the wheel motor
Figure SMS_178
With maximum motor power
Figure SMS_180
The smaller value of
Figure SMS_182
, where
Figure SMS_184
is the motor speed after shifting,
Figure SMS_176
Motor speed after shifting
Figure SMS_179
Maximum motor torque under .

步骤5：基于综合制动力分配策略，对轮上电机制动力和液压制动力进行分配：Step 5: Based on the comprehensive braking force distribution strategy, the electric motor braking force and hydraulic braking force on the wheel are distributed:

若换挡前的轮上电机制动功率储备

Figure SMS_185
和换挡后的轮上电机制动功率储备
Figure SMS_186
均大于等于车辆所需求的制动功率
Figure SMS_187
，则轮上电机制动力和液压制动力根据S1中轮上电机制动力能够满足需求制动力的情况进行分配；If the on-wheel motor braking power reserve before shifting
Figure SMS_185
And the on-wheel motor braking power reserve after gear shifting
Figure SMS_186
Both are greater than or equal to the braking power required by the vehicle
Figure SMS_187
, then the wheel motor force and hydraulic braking force are distributed according to whether the wheel motor force in S1 can meet the required braking force;

若换挡前的轮上电机制动功率储备

Figure SMS_188
或换挡后的轮上电机制动功率储备
Figure SMS_189
小于车辆所需求的制动功率
Figure SMS_190
，则轮上电机制动力和液压制动力根据S1中轮上电机制动力不足以满足需求制动力的情况进行分配。If the on-wheel motor braking power reserve before shifting
Figure SMS_188
Or the on-wheel motor braking power reserve after gear shifting
Figure SMS_189
Less than the braking power required by the vehicle
Figure SMS_190
, the wheel motor force and hydraulic braking force are allocated according to the situation in S1 where the wheel motor force is insufficient to meet the required braking force.

步骤6：根据步骤2中当前挡位

Figure SMS_191
之外各换挡的电机转速
Figure SMS_192
和电机扭矩
Figure SMS_193
，得到当前挡位
Figure SMS_194
之外各挡位轮上电机制动效率
Figure SMS_195
，以及各挡位电池回收功率
Figure SMS_196
。Step 6: According to the current gear position in step 2
Figure SMS_191
The motor speed of each gear shift
Figure SMS_192
and motor torque
Figure SMS_193
, get the current gear
Figure SMS_194
Other gears on the wheel motor braking efficiency
Figure SMS_195
, and battery recovery power in each gear
Figure SMS_196
.

步骤7：基于电池回收功率对换挡规律进行约束：选取当前挡位

Figure SMS_197
之外各挡位的电池回收功率
Figure SMS_198
中的最大值
Figure SMS_199
，并与换挡前电池回收功率
Figure SMS_200
进行比较，如果
Figure SMS_201
大于
Figure SMS_202
，跳转至步骤8，否则令
Figure SMS_203
，并返回步骤1。Step 7: Constrain the shift schedule based on battery recovery power: Select the current gear
Figure SMS_197
Battery recovery power in all other gears
Figure SMS_198
The maximum value in
Figure SMS_199
and recover power from the battery before shifting
Figure SMS_200
For comparison, if
Figure SMS_201
Greater than
Figure SMS_202
, jump to step 8, otherwise let
Figure SMS_203
, and return to step 1.

步骤8：进行换挡，目标挡位为

Figure SMS_204
对应的挡位；换挡完成后返回步骤1，并令
Figure SMS_205
，对换挡次数进行累计。Step 8: Shift gears to the target gear position.
Figure SMS_204
After the gear shift is completed, return to step 1 and set
Figure SMS_205
, the number of gear shifts is accumulated.

4、基于经济性的最优挡位分布执行降档操作4. Perform downshifts based on the optimal gear distribution for economy

采用上面3所制定的基于经济性的能量回收过程换挡规律，以车速200km/h为初始速度，设置制动踏板开度以此从100%开始到0%，遍历计算出最大电池制动功率对应的挡位，得到基于经济性的最优挡位分布。在能量回收过程中，车速逐渐降低，车辆状态呈现从右至左的车速趋势，当获取到车速和制动踏板开度时，得到当前工况下的挡位。Adopt the energy recovery process shifting rule based on economy formulated in 3 above, take the vehicle speed of 200km/h as the initial speed, set the brake pedal opening from 100% to 0%, traverse and calculate the gear corresponding to the maximum battery braking power, and obtain the optimal gear distribution based on economy. During the energy recovery process, the vehicle speed gradually decreases, and the vehicle state shows a speed trend from right to left. When the vehicle speed and brake pedal opening are obtained, the gear under the current working condition is obtained.

如图7所示，车速步长取1km/h，踏板开度步长取1%，每一小格代表相对应车速和踏板开度下最高能量回收率所对应的挡位，车辆状态改变时，挡位发生改变。以制动踏板开度10%为界限，在制动踏板开度大于10%时，换挡规律近似于单参数换挡规律，即换挡时机仅仅与车速有关，此时电机工作在高功率区间，降挡的需求主要来自于电机转速下降而导致的电机极限功率下降。当制动踏板开度小于10%时，换挡规律不仅与车速有关还与制动踏板开度有关，即在相同车速下不同制动踏板开度的换挡时机不相同，此时电机工作在低功率区间，降挡的需求主要来自于将电机工作点从低功率低效率区间转移至低功率高效率区间。As shown in Figure 7, the speed step is 1km/h, the pedal opening step is 1%, and each small grid represents the gear corresponding to the highest energy recovery rate under the corresponding speed and pedal opening. When the vehicle state changes, the gear changes. Taking the brake pedal opening of 10% as the limit, when the brake pedal opening is greater than 10%, the shifting rule is similar to the single-parameter shifting rule, that is, the shifting timing is only related to the vehicle speed. At this time, the motor works in the high-power range, and the demand for downshifting mainly comes from the decrease in the motor's limit power caused by the decrease in motor speed. When the brake pedal opening is less than 10%, the shifting rule is not only related to the vehicle speed but also to the brake pedal opening, that is, the shifting timing of different brake pedal openings at the same speed is different. At this time, the motor works in the low-power range, and the demand for downshifting mainly comes from transferring the motor working point from the low-power and low-efficiency range to the low-power and high-efficiency range.

显然，上述实施例仅仅是为清楚地说明所作的举例，而并非对实施方式的限定。对于所属领域的普通技术人员来说，在上述说明的基础上还可以做出其它不同形式的变化或变动。这里无需也无法对所有的实施方式予以穷举。而由此所引伸出的显而易见的变化或变动仍处于本发明创造的保护范围之中。Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the protection scope of the invention.

Claims (6)

1.再生制动下电机工作点选择及换挡规律制定方法，其特征在于，包括以下步骤：1. A method for selecting a motor operating point and formulating a shifting rule under regenerative braking, characterized in that it comprises the following steps: S1、制定综合制动力分配策略S1. Formulate a comprehensive braking force distribution strategy 基于轮上电机制动力是否能够满足需求制动力的判断条件，对轮上电机制动力与液压制动力的分配进行协调控制：一是轮上电机制动力能够满足需求制动力，则不需要液压制动力；二是轮上电机制动力不足以满足需求制动力，不足的部分由液压制动力来补充；Based on the judgment condition of whether the wheel electric machine force can meet the required braking force, the distribution of the wheel electric machine force and the hydraulic braking force is coordinated and controlled: first, if the wheel electric machine force can meet the required braking force, then hydraulic braking force is not needed; second, if the wheel electric machine force is not enough to meet the required braking force, the insufficient part is supplemented by hydraulic braking force; S2、换挡时电机工作点的选择策略S2, Motor operating point selection strategy during gear shifting 根据S1中的两种情形，对电机工作点进行如下选择：一是轮上电机制动力能够满足需求制动力，通过换挡将电机工作点沿着等功率曲线移动至等功率高效率区间，此时轮上电机制动力不变；二是轮上电机制动力不足以满足需求制动力，通过换挡将电机工作点转移至电机高功率区间，此时轮上电机制动力发生变化；According to the two situations in S1, the motor working point is selected as follows: one is that the wheel motor force can meet the required braking force, and the motor working point is moved to the equal power high efficiency interval along the equal power curve by shifting gears, and the wheel motor force remains unchanged; the other is that the wheel motor force is not enough to meet the required braking force, and the motor working point is transferred to the motor high power interval by shifting gears, and the wheel motor force changes; S3、确定能量回收过程中换挡规律，并执行换挡S3: Determine the shifting rules during energy recovery and execute the shifting 将S2中制定的选择策略作为换挡规律制定的约束条件之一，即换挡前后最大轮上电机制动力和需求制动力对换挡时电机工作点选择的约束；此外，约束条件还包括电机转速和电池回收功率；然后基于约束条件，制定基于经济性的能量回收过程中换挡规律并结合驾驶过程中的实际情况进行换挡；The selection strategy formulated in S2 is used as one of the constraints for the formulation of the shifting schedule, that is, the maximum wheel motor force and required braking force before and after the shifting constrain the selection of the motor operating point during the shifting; in addition, the constraints also include the motor speed and the battery recovery power; then, based on the constraints, a shifting schedule based on the economic energy recovery process is formulated and the shifting is performed in combination with the actual situation during driving; 在S1中，对轮上电机制动力与液压制动力的分配进行协调控制，根据不同制动工况下的制动强度的大小，分为以下五种情形：In S1, the distribution of the electric motor force and the hydraulic braking force on the wheel is coordinated and controlled. According to the braking intensity under different braking conditions, it is divided into the following five situations: （1）在轻度制动时，制动强度z满足条件
Figure QLYQS_1
时，仅在前轴上提供制动力，z表示制动强度，根据制动踏板开度确定，数值在0-1之间；z A 表示轻度制动时最低制动强度的门限值，前后轴需求制动力按照下式确定：(1) During light braking, the braking intensity z satisfies the condition
Figure QLYQS_1
When the brake pedal is turned on, only the front axle is provided with braking force. z represents the braking intensity, which is determined by the brake pedal opening and has a value between 0 and 1. z A represents the threshold value of the minimum braking intensity during light braking. The required braking force of the front and rear axles is determined according to the following formula:
Figure QLYQS_2
Figure QLYQS_2
 其中，z A 通过下式求得：Among them, z A is obtained by the following formula:
Figure QLYQS_3
Figure QLYQS_3
 式中，F Brake,Front 和F Brake,Rear 分别表示前轴和后轴的需求制动力，m为车辆质量，L a 和L b 分别表示车辆质心到前轴和后轴的距离，g表示重力加速度，h g 表示车辆质心高度；Where, F Brake,Front and F Brake,Rear represent the required braking forces of the front axle and rear axle respectively, m is the vehicle mass, La and Lb represent the distances from the vehicle center of mass to the front axle and rear axle respectively, g represents the acceleration of gravity, and hg represents the height of the vehicle center of mass; 若轮上电机制动力足以满足前轴需求制动力，前后轴上的需求制动力构成如下式：If the wheel motor force is sufficient to meet the required braking force on the front axle, the required braking force on the front and rear axles is formed as follows:
Figure QLYQS_4
Figure QLYQS_4
 式中，F MotorBrake 表示轮上电机制动力，F HydraulicBrake,Front 表示前轮液压制动力，F HydraulicBrake,Rear 表示后轮液压制动力；Where, F MotorBrake represents the motor force on the wheel, F HydraulicBrake,Front represents the hydraulic braking force of the front wheel, and F HydraulicBrake,Rear represents the hydraulic braking force of the rear wheel; 若轮上电机制动力不足以满足前轴需求制动力，则通过前轮液压制动力提供额外的制动力；前后轴上的需求制动力构成如下式：If the electric motor force on the wheel is not enough to meet the required braking force on the front axle, the front wheel hydraulic braking force will provide additional braking force; the required braking force on the front and rear axles is composed of the following formula:
Figure QLYQS_5
Figure QLYQS_5
 F MotorBrake_max 表示最大轮上电机制动力； F MotorBrake_max represents the maximum wheel motor force; （2）当制动强度z满足
Figure QLYQS_6
时，其中z B =0.5，前后轴需求制动力分配如下：(2) When the braking intensity z satisfies
Figure QLYQS_6
When z B = 0.5, the required braking force distribution of the front and rear axles is as follows:
Figure QLYQS_7
Figure QLYQS_7
 式中，k b =0.99表示制动力分配安全系数；In the formula, k b =0.99 represents the braking force distribution safety factor; 若轮上电机制动力足以满足前轴需求制动力，前后轴上的需要制动力构成如下式：If the wheel motor force is sufficient to meet the required braking force on the front axle, the required braking force on the front and rear axles is formed as follows:
Figure QLYQS_8
Figure QLYQS_8
 若轮上电机制动力不足以满足前轴需求制动力，则通过前轮液压制动力提供额外的制动力；其前后轴上的需求制动力构成如下式：If the electric motor force on the wheel is not enough to meet the required braking force of the front axle, the additional braking force is provided by the front wheel hydraulic braking force; the required braking force on the front and rear axles is composed of the following formula:
Figure QLYQS_9
；
Figure QLYQS_9
; （3）当制动强度z满足
Figure QLYQS_10
时，其中，z C =0.65，前后轴上的需求制动力分配如下式：(3) When the braking intensity z satisfies
Figure QLYQS_10
When z C =0.65, the required braking force distribution on the front and rear axles is as follows:
Figure QLYQS_11
Figure QLYQS_11
 若轮上电机制动力足以满足前轴需求制动力，前后轴上的需求制动力构成如下式：If the wheel motor force is sufficient to meet the required braking force on the front axle, the required braking force on the front and rear axles is formed as follows:
Figure QLYQS_12
Figure QLYQS_12
 若轮上电机制动力不足以满足前轴需求制动力，则通过前轮轮上液压制动力提供额外的制动力；前后轴上的需求制动力构成如下式：If the on-wheel electric brake force is insufficient to meet the required braking force on the front axle, the additional braking force is provided by the hydraulic brake force on the front wheels; the required braking force on the front and rear axles is formed as follows:
Figure QLYQS_13
；
Figure QLYQS_13
; （4）当制动强度z满足
Figure QLYQS_14
时，其中z D =1，前后轴上的需求制动力分配如下式：(4) When the braking intensity z satisfies
Figure QLYQS_14
When z D = 1, the required braking force distribution on the front and rear axles is as follows:
Figure QLYQS_15
Figure QLYQS_15
 其中，
Figure QLYQS_16
表示路面附着系数；in,
Figure QLYQS_16
It represents the road adhesion coefficient; 若轮上电机制动力足以满足前轴需求制动力，前后轴上的需求制动力构成如下式：If the wheel motor force is sufficient to meet the required braking force on the front axle, the required braking force on the front and rear axles is formed as follows:
Figure QLYQS_17
Figure QLYQS_17
 若轮上电机制动力不足以满足前轴需求制动力，则通过前轮轮上液压制动力提供额外的制动力；前后轴上的需求制动力构成如下式：If the on-wheel electric brake force is insufficient to meet the required braking force on the front axle, the additional braking force is provided by the hydraulic brake force on the front wheels; the required braking force on the front and rear axles is formed as follows:
Figure QLYQS_18
；
Figure QLYQS_18
; （5）当
Figure QLYQS_19
时，全液压制动，车辆处于紧急制动状态，为保证车辆在制动过程中的稳定性，在紧急制动状态下电机不参与制动，即前轮制动力全部由前轮液压制动力提供，前后轴上的需求制动力按如下公式分配：(5) When
Figure QLYQS_19
When the vehicle is in emergency braking state, full hydraulic braking is used. To ensure the stability of the vehicle during braking, the motor does not participate in braking in emergency braking state, that is, the front wheel braking force is entirely provided by the front wheel hydraulic braking force. The required braking force on the front and rear axles is distributed according to the following formula:
Figure QLYQS_20
；
Figure QLYQS_20
; 前后轴上的需求制动力构成如下式：The required braking force on the front and rear axles is formed as follows:
Figure QLYQS_21
。
Figure QLYQS_21
. 2.根据权利要求1所述的再生制动下电机工作点选择及换挡规律制定方法，其特征在于，在S2中，换挡时对电机工作点的选择分以下三种情形：2. The method for selecting the motor operating point and formulating the shifting rule under regenerative braking according to claim 1 is characterized in that, in S2, the selection of the motor operating point during the shifting is divided into the following three situations: 情形1：换挡前、后的轮上电机制动力≥需求制动力时，即换挡前轮上电机制动功率储备值
Figure QLYQS_22
和换挡后轮上电机制动功率储备值
Figure QLYQS_23
均大于需求制动功率
Figure QLYQS_24
；电机工作点沿功率值为
Figure QLYQS_25
的等功率线移动至转速值为
Figure QLYQS_26
对应位置；Case 1: When the electric motor braking force on the wheels before and after the gear shift is greater than the required braking force, that is, the electric motor braking power reserve value on the wheels before the gear shift
Figure QLYQS_22
And the motor braking power reserve value on the rear wheel after shifting
Figure QLYQS_23
Both are greater than the required braking power
Figure QLYQS_24
; The power value of the motor working point is
Figure QLYQS_25
The equal power line moves to the speed value of
Figure QLYQS_26
Corresponding position; 情形2：换挡前、后的轮上电机制动力＜需求制动力时，即换挡前轮上电机制动功率储备值
Figure QLYQS_27
和换挡后轮上电机制动功率储备值
Figure QLYQS_28
均小于需求制动功率
Figure QLYQS_29
；电机工作点首先沿功率值为
Figure QLYQS_30
的等功率线移动至转速值为
Figure QLYQS_31
对应位置，再沿转速值为
Figure QLYQS_32
的等转速线移动至换挡后轮上电机制动功率储备值
Figure QLYQS_33
的位置；Case 2: When the electric motor braking force on the wheels before and after the gear shift is less than the required braking force, that is, the motor braking power reserve value on the wheels before the gear shift
Figure QLYQS_27
And the motor braking power reserve value on the rear wheel after shifting
Figure QLYQS_28
Both are less than the required braking power
Figure QLYQS_29
; The motor working point first moves along the power value
Figure QLYQS_30
The equal power line moves to the speed value of
Figure QLYQS_31
Corresponding position, then along the speed value
Figure QLYQS_32
The constant speed line moves to the motor braking power reserve value on the rear wheel after shifting
Figure QLYQS_33
location; 情形3：换挡前轮上电机制动力＜需求制动力，换挡后的轮上电机制动力≥需求制动力时，即换挡前轮上电机制动功率储备值
Figure QLYQS_35
小于需求制动功率
Figure QLYQS_37
，换挡后轮上电机制动功率储备值
Figure QLYQS_39
大于等于需求制动功率
Figure QLYQS_36
；电机工作点首先沿功率值为
Figure QLYQS_38
的等功率线移动至转速值为
Figure QLYQS_40
对应的位置，再沿转速值为
Figure QLYQS_41
的等转速线移动至需求制动功率
Figure QLYQS_34
的位置；Case 3: When the electric motor force on the wheel before shifting is less than the required braking force, and the electric motor force on the wheel after shifting is greater than the required braking force, that is, the motor braking power reserve value on the wheel before shifting
Figure QLYQS_35
Less than required braking power
Figure QLYQS_37
, after shifting, the motor braking power reserve value on the wheel
Figure QLYQS_39
Greater than or equal to the required braking power
Figure QLYQS_36
; The motor working point first moves along the power value
Figure QLYQS_38
The equal power line moves to the speed value of
Figure QLYQS_40
The corresponding position, and then along the speed value
Figure QLYQS_41
The constant speed line moves to the required braking power
Figure QLYQS_34
location; 情形1-3中，
Figure QLYQS_42
表示换挡前，
Figure QLYQS_43
表示换挡后，
Figure QLYQS_44
为换挡后电机处于高效率区间下的转速。In situations 1-3,
Figure QLYQS_42
Indicates before shifting gears,
Figure QLYQS_43
Indicates that after shifting gears,
Figure QLYQS_44
It is the speed at which the motor is in the high efficiency range after shifting. 3.根据权利要求1所述的再生制动下电机工作点选择及换挡规律制定方法，其特征在于，在S3中，确定能量回收过程中换挡规律的具体步骤如下：3. The method for selecting the motor operating point and formulating the shifting rule under regenerative braking according to claim 1 is characterized in that, in S3, the specific steps of determining the shifting rule during the energy recovery process are as follows: S3-1：当车辆控制器识别到驾驶员需要制动时，获取换挡前车辆状态参数，包括当前车速
Figure QLYQS_47
，当前制动强度
Figure QLYQS_49
，当前车辆挡位
Figure QLYQS_58
，换挡前电池回收功率
Figure QLYQS_50
，电池荷电状态
Figure QLYQS_62
；判断当前车速
Figure QLYQS_52
是否为0，若为0，则返回S3-1；若当前车速
Figure QLYQS_59
不为0，则继续判断当前电池荷电状态
Figure QLYQS_53
是否大于等于电池荷电状态最大值
Figure QLYQS_61
，若当前电池荷电状态
Figure QLYQS_45
大于等于电池荷电状态最大值
Figure QLYQS_55
，则返回S3-1；若当前电池荷电状态
Figure QLYQS_46
小于电池荷电状态最大值
Figure QLYQS_56
，则继续判断当前制动强度
Figure QLYQS_51
是否为0，若当前制动强度
Figure QLYQS_57
为0，则返回S3-1；若当前制动强度
Figure QLYQS_54
不为0，继续执行S3-2；其中，下标
Figure QLYQS_60
表示当前循环为第
Figure QLYQS_48
次循环；S3-1: When the vehicle controller recognizes that the driver needs to brake, obtain the vehicle state parameters before shifting, including the current vehicle speed
Figure QLYQS_47
, current braking intensity
Figure QLYQS_49
, current vehicle gear
Figure QLYQS_58
, battery recovery power before shifting
Figure QLYQS_50
, battery state of charge
Figure QLYQS_62
; Determine the current vehicle speed
Figure QLYQS_52
Is it 0? If it is 0, return to S3-1; if the current speed
Figure QLYQS_59
If it is not 0, continue to judge the current battery charge state
Figure QLYQS_53
Is it greater than or equal to the maximum value of the battery state of charge?
Figure QLYQS_61
If the current battery state of charge
Figure QLYQS_45
Greater than or equal to the maximum battery state of charge
Figure QLYQS_55
, then return to S3-1; if the current battery charge state
Figure QLYQS_46
Less than the maximum battery state of charge
Figure QLYQS_56
, then continue to judge the current braking intensity
Figure QLYQS_51
Is it 0? If the current braking strength
Figure QLYQS_57
is 0, then return to S3-1; if the current braking intensity
Figure QLYQS_54
If it is not 0, continue to execute S3-2;
Figure QLYQS_60
Indicates that the current cycle is
Figure QLYQS_48
Secondary cycle; S3-2：基于电机转速对换挡规律进行约束：基于变速箱速比计算当前挡位
Figure QLYQS_64
换至其余各挡位
Figure QLYQS_68
对应的电机转速
Figure QLYQS_69
；根据电机转速
Figure QLYQS_65
得到对应最大电机功率
Figure QLYQS_67
；由需求制动力求得车辆的需求制动功率
Figure QLYQS_70
，判断
Figure QLYQS_71
是否小于等于最大电机转速
Figure QLYQS_63
；若是，则跳转至S3-3；否则，不执行换挡，令
Figure QLYQS_66
并返回S3-1；S3-2: Constrain the shifting schedule based on the motor speed: Calculate the current gear based on the gearbox ratio
Figure QLYQS_64
Shift to other gears
Figure QLYQS_68
Corresponding motor speed
Figure QLYQS_69
; According to the motor speed
Figure QLYQS_65
Get the corresponding maximum motor power
Figure QLYQS_67
; The required braking power of the vehicle is obtained from the required braking force
Figure QLYQS_70
,judge
Figure QLYQS_71
Is it less than or equal to the maximum motor speed?
Figure QLYQS_63
; If yes, jump to S3-3; otherwise, do not execute the gear shift,
Figure QLYQS_66
And return to S3-1; S3-3：基于S2的电机工作点的选择策略对换挡规律进行约束；S3-3: constrain the shifting schedule based on the motor operating point selection strategy of S2; S3-4：根据约束条件，得到挡位
Figure QLYQS_73
所对应的电机回收功率
Figure QLYQS_77
；电机回收功率
Figure QLYQS_79
等于轮上电机制动需求功率
Figure QLYQS_74
与最大电机功率
Figure QLYQS_76
中的较小值，其中，
Figure QLYQS_78
，式中，
Figure QLYQS_80
为换挡后的电机转速，
Figure QLYQS_72
为换挡后电机转速
Figure QLYQS_75
下的最大电机扭矩；S3-4: Get the gear position according to the constraints
Figure QLYQS_73
Corresponding motor recovery power
Figure QLYQS_77
; Motor recovery power
Figure QLYQS_79
Equal to the braking power required by the wheel motor
Figure QLYQS_74
With maximum motor power
Figure QLYQS_76
The smaller value of
Figure QLYQS_78
, where
Figure QLYQS_80
is the motor speed after shifting,
Figure QLYQS_72
Motor speed after shifting
Figure QLYQS_75
Maximum motor torque under ; S3-5：基于S1的所述综合制动力分配策略，对轮上电机制动力和液压制动力进行分配：S3-5: Based on the comprehensive braking force distribution strategy of S1, the electric motor braking force and the hydraulic braking force on the wheel are distributed: 若换挡前的轮上电机制动功率储备
Figure QLYQS_81
和换挡后的轮上电机制动功率储备
Figure QLYQS_82
均大于等于车辆所需求的制动功率
Figure QLYQS_83
，则轮上电机制动力和液压制动力根据S1中轮上电机制动力能够满足需求制动力的情况进行分配；If the on-wheel motor braking power reserve before shifting
Figure QLYQS_81
And the on-wheel motor braking power reserve after gear shifting
Figure QLYQS_82
Both are greater than or equal to the braking power required by the vehicle
Figure QLYQS_83
, then the wheel motor force and hydraulic braking force are distributed according to whether the wheel motor force in S1 can meet the required braking force; 若换挡前的轮上电机制动功率储备
Figure QLYQS_84
或换挡后的轮上电机制动功率储备
Figure QLYQS_85
小于车辆所需求的制动功率
Figure QLYQS_86
，则轮上电机制动力和液压制动力根据S1中轮上电机制动力不足以满足需求制动力的情况进行分配；If the on-wheel motor braking power reserve before shifting
Figure QLYQS_84
Or the on-wheel motor braking power reserve after gear shifting
Figure QLYQS_85
Less than the braking power required by the vehicle
Figure QLYQS_86
, then the wheel motor force and hydraulic braking force are allocated according to the situation that the wheel motor force in S1 is insufficient to meet the required braking force; S3-6：根据S3-2中当前挡位
Figure QLYQS_87
之外各换挡的电机转速
Figure QLYQS_88
和电机扭矩
Figure QLYQS_89
，得到当前挡位
Figure QLYQS_90
之外各挡位轮上电机制动效率
Figure QLYQS_91
，以及各挡位电池回收功率
Figure QLYQS_92
；S3-6: According to the current gear position in S3-2
Figure QLYQS_87
Motor speed for each gear shift
Figure QLYQS_88
and motor torque
Figure QLYQS_89
, get the current gear
Figure QLYQS_90
Other gears on the wheel motor braking efficiency
Figure QLYQS_91
, and battery recovery power in each gear
Figure QLYQS_92
; S3-7：基于电池回收功率对换挡规律进行约束：选取当前挡位
Figure QLYQS_93
之外各挡位的电池回收功率
Figure QLYQS_94
中的最大值
Figure QLYQS_95
，并与换挡前电池回收功率
Figure QLYQS_96
进行比较，如果
Figure QLYQS_97
大于
Figure QLYQS_98
，跳转至S3-8，否则令
Figure QLYQS_99
，并返回S3-1 ；S3-7: Constrain the shifting schedule based on battery recovery power: Select the current gear
Figure QLYQS_93
Battery recovery power in all other gears
Figure QLYQS_94
The maximum value in
Figure QLYQS_95
and recover power from the battery before shifting
Figure QLYQS_96
For comparison, if
Figure QLYQS_97
Greater than
Figure QLYQS_98
, jump to S3-8, otherwise
Figure QLYQS_99
, and return to S3-1; S3-8：进行换挡，目标挡位为
Figure QLYQS_100
对应的挡位；换挡完成后返回S3-1，并令
Figure QLYQS_101
，对换挡次数进行累计。S3-8: Shift gears, target gear is
Figure QLYQS_100
After the gear shift is completed, return to S3-1 and make
Figure QLYQS_101
, the number of gear shifts is accumulated. 4.根据权利要求3所述的再生制动下电机工作点选择及换挡规律制定方法，其特征在于，在S3中的约束条件具体为：若当前最大电机功率
Figure QLYQS_107
大于车辆的需求制动功率
Figure QLYQS_105
，则电机的工作点沿功率值为
Figure QLYQS_118
的等功率线移动至转速值为
Figure QLYQS_109
对应位置；否则获取换挡后的轮上电机制动功率储备值
Figure QLYQS_114
和车辆的需求制动功率
Figure QLYQS_110
，若
Figure QLYQS_116
＞P B ，则电机工作点先沿功率值为
Figure QLYQS_108
的等功率线移动至转速值为
Figure QLYQS_117
对应位置，再沿转速值为
Figure QLYQS_102
对应的转速线移动到车辆的需求制动功率
Figure QLYQS_111
；若
Figure QLYQS_104
<
Figure QLYQS_115
，则电机工作点先沿功率值为
Figure QLYQS_106
的等功率线移动至转速值为
Figure QLYQS_113
对应位置，再沿转速值为
Figure QLYQS_103
对应的转速线移动到轮上电机制动功率储备值
Figure QLYQS_112
。4. The method for selecting the motor operating point and formulating the shifting rule under regenerative braking according to claim 3 is characterized in that the constraint condition in S3 is specifically: if the current maximum motor power
Figure QLYQS_107
Greater than the vehicle's required braking power
Figure QLYQS_105
, then the motor's operating point along the power value is
Figure QLYQS_118
The equal power line moves to the speed value of
Figure QLYQS_109
Corresponding position; otherwise, obtain the on-wheel motor braking power reserve value after gear shifting
Figure QLYQS_114
and the vehicle's required braking power
Figure QLYQS_110
,like
Figure QLYQS_116
> PB , then the motor working point first edge power value is
Figure QLYQS_108
The equal power line moves to the speed value of
Figure QLYQS_117
Corresponding position, then along the speed value
Figure QLYQS_102
The corresponding speed line moves to the required braking power of the vehicle
Figure QLYQS_111
;like
Figure QLYQS_104
<
Figure QLYQS_115
, then the power value of the motor working point is
Figure QLYQS_106
The equal power line moves to the speed value of
Figure QLYQS_113
Corresponding position, then along the speed value
Figure QLYQS_103
The corresponding speed line moves to the wheel motor braking power reserve value
Figure QLYQS_112
. 5.根据权利要求1所述的再生制动下电机工作点选择及换挡规律制定方法，其特征在于，还包括，S4、基于S3制定的换挡规律，制作最优挡位分布图：5. The method for selecting the motor working point and formulating the shifting rule under regenerative braking according to claim 1, characterized in that it also includes, S4, making an optimal gear distribution diagram based on the shifting rule formulated in S3: 根据S3中制定的换挡规律，以车速200km/h为初始速度，设置制动踏板开度从100%到0%，遍历出不同车速和制动踏板开度下的最大电池回收功率对应的挡位，即为最优挡位，进而得到基于经济性的不同车速和制动踏板开度下最优挡位分布图。According to the shifting rules formulated in S3, with a vehicle speed of 200 km/h as the initial speed, the brake pedal opening is set from 100% to 0%, and the gear corresponding to the maximum battery recovery power at different vehicle speeds and brake pedal openings is traversed, which is the optimal gear. Then, the optimal gear distribution map at different vehicle speeds and brake pedal openings based on economy is obtained. 6.根据权利要求5所述的再生制动下电机工作点选择及换挡规律制定方法，其特征在于，在制作最优挡位分布图时，设置车速步长为1km/h，制动踏板开度步长为1%。6. The method for selecting the motor operating point and formulating the shifting rule under regenerative braking according to claim 5 is characterized in that when making the optimal gear distribution map, the vehicle speed step size is set to 1 km/h and the brake pedal opening step size is set to 1%.
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