Energy recovery control method and system

Abstract

Provided are an energy recovery control method and system. The method comprises: on the basis of the opening degree of a brake pedal, determining a torque control mode; on the basis of the torque control mode, determining a desired electric braking torque and / or a desired mechanical braking torque of a vehicle; and on the basis of the desired electric braking torque and / or the desired mechanical braking torque, controlling an electric motor and / or a mechanical braking system of the vehicle. By designing the relationship between the opening degree of a brake pedal and a desired total braking torque, the decelerations being different at the same opening degree of the brake pedal due to changes in road and slope factors is avoided, thereby improving the brake pedal feel; and safety risks arising from misjudgments of a driver due to environmental factors are avoided. Regardless of the state of charge and fault state of a power system, braking torques can be kept consistent at the same vehicle speed by adjusting electric braking and mechanical braking, so as to avoid an abrupt forward acceleration of a vehicle due to sudden reduction or exit of electric braking when electric braking is limited during coasting, thereby avoiding safety issues and also improving the driving experience.

Description

Energy recovery control method and system Cross-reference to related applications

[0001] This application claims priority to Chinese Patent Application No. 202410807315.0, filed on June 21, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0002] The present application belongs to the technical field of vehicle energy recovery, and specifically relates to an energy recovery control method and system. BACKGROUND

[0003] With the development of new energy vehicles, pure electric vehicles and hybrid electric vehicles are becoming more and more popular in the market. Such vehicles are equipped with energy recovery function. In the current vehicle energy recovery control process, the sliding energy recovery and the braking energy recovery are superimposed. Due to the inability to match and coordinate the electric brake and the mechanical brake, the brake pedal feel is poor. The sliding energy recovery and the braking energy recovery cannot be smoothly transitioned, and the vehicle may even suddenly accelerate when sliding to brake. The energy recovery cannot be fully utilized. SUMMARY

[0004] In order to improve the brake pedal feel during energy recovery in the braking process, improve the utilization rate of vehicle energy recovery, avoid unexpected acceleration during energy recovery, and improve the safety and driving experience of the vehicle, the present application proposes an energy recovery control method and system.

[0005] An energy recovery control method for achieving one of the purposes of the present application, comprising:

[0006] determining the current torque control mode according to the brake pedal opening;

[0007] determining the desired electric brake torque and / or the desired mechanical brake torque of the vehicle according to the current torque control mode;

[0008] controlling the motor and / or the mechanical brake system of the vehicle according to the desired electric brake torque and / or the desired mechanical brake torque, and controlling the actual electric brake torque and / or the actual mechanical brake torque to achieve the desired total brake torque, wherein the desired total brake torque is equal to the sum of the desired electric brake torque and the desired mechanical brake torque.

[0009] Further, when the brake pedal opening is equal to 0, the torque control mode is the sliding mode;

[0010] When the brake pedal opening is less than or equal to a set threshold, the torque control mode is the adaptive mode;

[0011] When the brake pedal opening is greater than the set threshold, the torque control mode is the braking mode.

[0012] Further, the torque control mode includes a coasting mode, when in the coasting mode, the desired electric braking torque of the vehicle is equal to the coasting energy recovery torque, and the desired mechanical braking torque is 0.

[0013] Further, the torque control mode includes an adaptive mode, when in the adaptive mode, when the vehicle is coasting, the coasting energy recovery torque is not limited, then the desired electric braking torque is equal to the coasting energy recovery torque before entering the adaptive mode, and the desired mechanical braking torque is 0.

[0014] Further, the torque control mode includes an adaptive mode, when in the adaptive mode, when the vehicle is coasting, the coasting energy recovery torque is limited or the electric braking torque does not meet the desired deceleration, the actual electric braking torque that can be provided is determined according to the power system limit torque; the desired mechanical braking torque is determined according to the desired total braking torque and the actual required electric braking torque.

[0015] The method for determining the actual electric braking torque that can be provided according to the power system limit torque includes: the maximum allowed electric braking torque calculated by the maximum allowed charging power output by the power system is the actual electric braking torque that can be provided.

[0016] Further, the method for determining the desired mechanical braking torque according to the desired total braking torque and the actual required electric braking torque includes:

[0017] The desired mechanical braking torque is equal to the difference between the desired total braking torque and the actual required electric braking torque, and the actual required electric braking torque is calculated according to the power system limit torque.

[0018] Further, the method for determining the desired mechanical braking torque includes:

[0019] When the vehicle is switched from the coasting mode to the adaptive mode and the braking mode in sequence, the mechanical braking torque rises from 0 to the desired mechanical braking torque at a set slope;

[0020] When the vehicle is switched from the braking mode to the adaptive mode and the coasting mode in sequence, the mechanical braking torque decreases from the desired mechanical braking torque to 0 at a set slope.

[0021] Further, the method for calculating the slope includes:

[0022] K = (T0-T1) / P1

[0023] In the formula, K is the slope; T0 is the expected total braking torque calculated according to the expected deceleration when the power system is not limited and the vehicle control system does not limit energy recovery; T1 is the actual electric braking torque that can be provided calculated when the power system is limited or the vehicle control system limits energy recovery; P1 is a set brake pedal opening threshold value; when the brake pedal opening is less than or equal to the set brake pedal opening threshold value P1, the vehicle is in an adaptive mode; when the brake pedal opening is greater than the set brake pedal opening threshold value P1, the vehicle is in a braking mode.

[0024] When the vehicle control system is limited, the control system (VCU) limits the maximum energy recovery torque allowed according to the vehicle state, which is the actual electric braking torque that can be provided; when the power system is limited, the maximum allowed electric braking torque can be calculated by the maximum allowed charging power output by the power system, which is the actual electric braking torque that can be provided.

[0025] Further, the method for determining the expected deceleration comprises:

[0026] When the brake pedal opening is less than or equal to the set brake pedal opening threshold value P1, the expected deceleration is set according to the current coasting energy recovery level. The coasting energy recovery level includes weak, medium and strong, and the expected deceleration increases with the increase of the coasting energy recovery level.

[0027] When the brake pedal opening is greater than the set brake pedal opening threshold value P1, the brake pedal opening corresponding to each braking intensity coincides with the expected deceleration curve; under the same braking intensity, the expected deceleration increases with the increase of the brake pedal opening.

[0028] Further, the torque control mode includes a braking mode, when in the braking mode, the expected electric braking torque of the vehicle is equal to the maximum electric braking torque that can be provided by the vehicle at present; the expected mechanical braking torque is equal to the difference between the expected total braking torque and the maximum electric braking torque.

[0029] Further, the method for calculating the expected total braking torque comprises:

[0030] The expected deceleration is determined according to the brake pedal opening and the braking intensity;

[0031] The expected braking resistance of the vehicle is determined according to the expected deceleration;

[0032] The expected total braking torque is determined according to the expected braking resistance of the vehicle.

[0033] Further, the method for calculating the expected total braking torque further comprises:

[0034] Mb=[m×a-G×f×cosα-(CD×A×V 2) / 21.15-G x sin a] x r

[0035] Mb is the desired total braking torque; m is the vehicle mass; a is the desired deceleration of the vehicle; G is the vehicle weight, f is the rolling resistance coefficient, a is the slope; CD is the air resistance coefficient, A is the windward area, V is the vehicle speed; r is the wheel radius.

[0036] The energy recovery control system for achieving the second purpose of the application comprises:

[0037] The mode determination module is configured to determine the current torque control mode according to the brake pedal opening degree;

[0038] The torque distribution module is configured to determine the desired electric braking torque and / or the desired mechanical braking torque of the vehicle according to the current torque control mode;

[0039] The control module is configured to control the motor and the mechanical braking system of the vehicle according to the desired electric braking torque and / or the desired mechanical braking torque, respectively.

[0040] The beneficial effects of the application include:

[0041] In the definition of the relationship between the brake pedal opening degree and the desired total braking torque, the external resistance caused by the road, the slope and other factors is considered, so as to avoid the change of the deceleration under the same brake pedal opening degree caused by the change of the road, the slope and other factors, and to improve the brake pedal feeling. At the same time, it also avoids the safety risk caused by the misjudgment of the driver due to environmental factors, and improves the driving safety and driving feeling. No matter the state of the power system or the fault state of the power system, the electric braking and the mechanical braking can be adjusted to keep the braking torque consistent at the same vehicle speed, which improves the driving experience and avoids the problem of sudden acceleration of the vehicle when the electric braking is suddenly reduced / withdrawn due to the limitation of the electric braking during coasting. BRIEF DESCRIPTION OF DRAWINGS

[0042] Fig. 1 is a flowchart of the method technical solution of the application;

[0043] Fig. 2 is a schematic diagram of the brake pedal control interval in the method technical solution of the application;

[0044] Fig. 3 is a schematic diagram of the relationship between the brake pedal opening degree and the braking deceleration under different braking intensities in the method technical solution of the application;

[0045] Fig. 4 is a schematic diagram of the relationship between the brake pedal and the braking torque in the adaptive mode of the method technical solution of the application. DETAILED DESCRIPTION

[0046] The following specific embodiments are used to explain the technical solutions of the claims of the present application, so that those skilled in the art can understand the claims of the present application. The protection scope of the present application is not limited to the following specific embodiments. Those skilled in the art who make the technical solutions of the claims of the present application different from the following specific embodiments are also within the protection scope of the present application.

[0047] Technical solution 1

[0048] An energy recovery control method:

[0049] Step 1, define the brake pedal control interval;

[0050] In order to solve the seamless connection and smooth transition between coasting energy recovery and braking energy recovery, the brake pedal opening is divided into two intervals, and different torque controls are performed in different intervals, as shown in Figure 2; adaptive interval: define the interval of brake pedal opening from 0 to brake pedal opening threshold P1 (set to 18% in this technical solution, which can be calibrated), i.e. interval A as shown in Figure 2, in this adaptive interval, the expected total braking torque is a relatively stable value, and the maximum boundary of the expected total braking torque is limited, and the expected total braking torque is usually equal to the current coasting energy recovery torque under normal conditions, i.e. when the power system is not limited and the control system is not limited; braking interval: define the interval of brake pedal opening greater than the threshold P1 as interval B, i.e. interval B as shown in Figure 2, in this interval, the brake torque value increases with the increase of brake pedal opening.

[0051] Step 2, define the ideal expected deceleration corresponding to the brake pedal opening;

[0052] Usually, new energy vehicles are designed with three strength coasting energy recovery modes: weak, medium and strong. The technical solution of the present application keeps the braking energy recovery level consistent with the coasting energy recovery mode, i.e. the braking energy recovery levels: weak, medium and strong correspond one by one to the weak, medium and strong of the coasting energy recovery mode. In this way, when the user selects different coasting energy recovery modes, there is a corresponding braking energy recovery level, and the energy recovery from coasting energy recovery seamlessly transitions to braking energy recovery, and the electric brake torque smoothly transitions, improving the driving feeling and improving energy efficiency.

[0053] When the brake pedal opening is in the adaptive interval, since this section is consistent with coasting, there is usually an energy recovery level (such as weak, medium and strong, which usually corresponds one by one to the coasting energy recovery mode) set when coasting energy recovery, so the braking strength in the adaptive interval is also consistent with the energy recovery level set by the user; in the transition interval, the brake pedal opening of each braking strength coincides with the deceleration curve, so that the braking feeling and deceleration in the braking process are consistent with the driver's expectation, and the braking and safety requirements can be guaranteed.

[0054] According to the brake pedal opening degree, the expected deceleration is set, and the value and relationship diagram of the brake pedal opening degree and the expected deceleration are shown in Table 1 and Figure 3 respectively: that is, when the brake pedal opening degree is 0, the expected deceleration is equal to the expected deceleration when the vehicle is sliding; when the brake pedal opening degree is less than the set threshold P1, the expected deceleration increases with the increase of the brake intensity and the increase of the brake pedal opening degree; when the brake pedal opening degree is greater than or equal to the set threshold P1, the expected deceleration only increases with the increase of the brake pedal opening degree.

[0055] Table 1: Expected deceleration table

[0056]

[0057] Step 3, brake torque calculation;

[0058] When the automobile is decelerating, the total deceleration force of the automobile is composed of the rolling resistance F f , the wind resistance F w , the slope resistance F i , and the brake resistance F j . In a vehicle with energy recovery, the brake resistance F j includes the electric brake recovery force and the mechanical brake force.

[0059] The total resistance of the vehicle is F=m×a, m is the mass of the vehicle, and a is the expected deceleration of the vehicle;

[0060] The total resistance F=F f +F w +F i +F j

[0061] Wherein, the rolling resistance F f =G×f×cosα, G is the vehicle weight, f is the rolling resistance coefficient, and α is the slope;

[0062] The wind resistance F w =(CD×A×V 2 ) / 21.15, CD is the air resistance coefficient, A is the windward area, and V is the vehicle speed;

[0063] The slope resistance F i =G×sinα, G is the vehicle weight, and α is the slope;

[0064] The expected brake resistance F j =F-(F f +F w +F i )=m×a-G×f×cosα-(CD×A×V 2) / 21.15-Gxsin a

[0065] According to the desired braking resistance F j And the wheel radius r, the desired total braking torque Mb can be calculated:

[0066] Mb=F j x r=[mxa-Gxfxcos a-(CDxAxV 2 ) / 21.15-Gxsin a]x r

[0067] m is the vehicle mass;

[0068] a is the desired deceleration of the vehicle, obtained by looking up Table 1;

[0069] Step 4, dynamic control of the desired total braking torque;

[0070] According to the brake pedal opening, three modes are defined: coasting mode, adaptive mode, and braking mode, wherein the brake pedal opening equal to 0 is defined as the coasting mode; the brake pedal opening in the interval (0, P1] is defined as the adaptive mode, and the brake pedal opening greater than P1 is defined as the braking mode. In the three modes, the coasting torque calculation, adaptive torque calculation, and braking torque calculation are respectively performed.

[0071] 1. Coasting energy recovery torque calculation in the coasting mode;

[0072] In the coasting mode, the desired electric braking torque is equal to the coasting energy recovery torque, and the desired electric braking torque obtained according to the energy recovery level, the set coasting deceleration, the vehicle speed, and the motor speed is the coasting energy recovery torque in the coasting mode. Since the coasting energy recovery torque is related to the vehicle state such as the vehicle speed, the power system state (such as the power battery SOC, the battery allowable charging power, etc.), the value also changes with the vehicle state, and thus the desired electric braking torque when the brake pedal opening is 0% is also dynamically changed. At this time, the desired mechanical braking torque is equal to 0. The set coasting deceleration is the desired deceleration determined according to the brake pedal opening and the braking intensity shown in Table 1. In control, the desired deceleration when coasting is equal to the desired deceleration in the adaptive interval, so that the deceleration is the same when coasting and braking are transitioned, the desired total braking torque is the same, and then seamless docking is achieved, so that the vehicle will not suddenly accelerate or decelerate due to different torques, and the coasting energy recovery torque is equal to the desired total braking torque Mb.

[0073] When transitioning from the adaptive mode to the coasting mode, the desired electric braking torque is equal to the smaller value of the electric braking torque when exiting the adaptive mode and the coasting energy recovery torque in the current coasting mode;

[0074] 2. Adaptive torque calculation in the adaptive mode;

[0075] 1)When the vehicle is coasting and the coasting energy recovery torque is not limited, the brake energy recovery torque (here also referred to as the desired electric brake torque) in the adaptive mode is equal to the coasting energy recovery torque before entering the adaptive mode, and the desired mechanical brake torque is 0. The limiting factors of the coasting energy recovery torque include: motor or battery system capability limitation or failure; the battery power such as SOC is higher than a set value, and energy recovery is not performed, which is a scenario in which the coasting energy recovery torque is limited, and the battery power is lower than the set value, and energy recovery is performed, which is a scenario in which the coasting energy recovery torque is not limited;

[0076] 2)When the vehicle is coasting and the coasting energy recovery torque is limited or the electric brake torque in the adaptive range does not meet the desired deceleration, the electric brake process at this time cannot provide sufficient electric brake torque, and the vehicle needs to provide additional mechanical brake torque to supplement the torque insufficient due to the limited coasting energy recovery torque. The desired mechanical brake torque at this time is equal to the desired total brake torque Mb minus the actual electric brake torque that can be provided, and the actual electric brake torque that can be provided is calculated according to the power system limitation (including motor state limitation, battery state limitation) torque.

[0077] When the vehicle changes from the adaptive range to the brake range, the mechanical brake torque is smoothly increased from 0 to the calculated desired mechanical brake torque (the desired total brake torque Mb minus the actual electric brake torque that can be provided) at a set slope K in the initial stage of the adaptive range. When the vehicle changes from the brake range to the adaptive range, the actual mechanical brake torque is smoothly decreased from the desired mechanical brake torque to 0 at a set slope K in the initial stage of the adaptive range, as shown in FIG. 4.

[0078] K= (T0-T1) / P1

[0079] T0 is the total brake torque in an ideal case, that is, the desired total brake torque Mb calculated according to the desired deceleration in the case where the power system is not limited and the vehicle control system does not limit.

[0080] T1 is the actual electric brake torque that can be provided calculated in the case where the power system is limited or the vehicle control system limits energy recovery under the current state of the vehicle.

[0081] The technical effect of the above technical steps is that the change of the mechanical brake torque at a certain slope K can avoid uneven change of the brake torque, thereby causing poor brake comfort.

[0082] 3. Mechanical brake torque calculation in brake mode;

[0083] In this mode, the principle of electric braking priority is adopted, and the maximum electric braking force is recovered. The maximum electric braking torque (the maximum power allowed by the power system / current motor speed) is calculated through the vehicle state (including the battery SOC, the maximum allowed charging power of the battery, and the motor speed). The desired mechanical braking torque is equal to the desired total braking torque Mb minus the maximum electric braking torque.

[0084] 4. Torque control;

[0085] The motor and the mechanical braking system are controlled according to the desired electric braking torque and the desired mechanical braking torque, respectively, to achieve the braking demand. The above adjustment of the electric braking torque and the mechanical braking torque is used to keep the braking torque consistent at the same vehicle speed, to meet the braking intention, and to maximize the energy recovery, improve the economy and comfort.

[0086] Technical solution 2

[0087] An energy recovery control method, comprising:

[0088] Determining the current torque control mode according to the brake pedal opening;

[0089] Determining the desired electric braking torque and / or the desired mechanical braking torque of the vehicle according to the current torque control mode;

[0090] Controlling the motor and / or the mechanical braking system of the vehicle according to the desired electric braking torque and / or the desired mechanical braking torque, respectively.

[0091] In some technical solutions, when the brake pedal opening is equal to 0, the torque control mode is the coasting mode; when the brake pedal opening is less than or equal to a set threshold, the torque control mode is the adaptive mode; and when the brake pedal opening is greater than the set threshold, the torque control mode is the braking mode.

[0092] In some technical solutions, the torque control mode includes the coasting mode, and when in the coasting mode, the desired electric braking torque of the vehicle is equal to the coasting energy recovery torque, and the desired mechanical braking torque is 0.

[0093] In some technical solutions, the torque control mode includes the adaptive mode, and when in the adaptive mode, when the coasting energy recovery torque is not limited when the vehicle is coasting, the desired electric braking torque is equal to the coasting energy recovery torque before entering the adaptive mode, and the desired mechanical braking torque is 0.

[0094] In some embodiments, the torque control mode comprises an adaptive mode, when the vehicle is in the adaptive mode, the regenerative torque is limited when the vehicle is coasting, or the electric braking torque does not meet the expected deceleration, the actual electric braking torque that can be provided is determined according to the power system limit torque, the expected mechanical braking torque is determined according to the expected total braking torque and the actual electric braking torque.

[0095] In some embodiments, when the vehicle is switched from the coasting mode to the adaptive mode and then to the braking mode, the mechanical braking torque increases from 0 to the expected mechanical braking torque at a set slope, and when the vehicle is switched from the braking mode to the adaptive mode and then to the coasting mode, the mechanical braking torque decreases from the expected mechanical braking torque to 0 at a set slope.

[0096] In some embodiments, the calculation method of the set slope comprises:

[0097] K=(T0-T1) / P1

[0098] In the formula, K is the set slope, T0 is the expected total braking torque calculated according to the expected deceleration when the power system is not limited and the vehicle control system does not limit energy recovery, T1 is the actual electric braking torque that can be provided calculated under the condition that the power system is limited or the vehicle control system limits energy recovery, and P1 is a set brake pedal opening threshold.

[0099] In some embodiments, the torque control mode comprises a braking mode, when the vehicle is in the braking mode, the expected electric braking torque of the vehicle is equal to the maximum electric braking torque that can be provided by the vehicle, and the expected mechanical braking torque is equal to the difference between the expected total braking torque and the maximum electric braking torque.

[0100] In some embodiments, the calculation method of the expected total braking torque comprises:

[0101] determining the expected deceleration according to the brake pedal opening and the braking intensity;

[0102] determining the expected braking resistance of the vehicle according to the expected deceleration;

[0103] determining the expected total braking torque according to the expected braking resistance of the vehicle.

[0104] It should be understood that the size of the serial number of each step in the above technical solutions does not mean the order of execution, the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the technical solutions of the present application.

[0105] Technical solution 3

[0106] An energy recovery control system comprises:

[0107] a mode determining module configured to determine a current torque control mode according to a brake pedal opening;

[0108] a torque distribution module configured to determine a desired electric brake torque and / or a desired mechanical brake torque of the vehicle according to the current torque control mode;

[0109] a control module configured to control an electric machine and a mechanical brake system of the vehicle according to the desired electric brake torque and / or the desired mechanical brake torque, respectively.

[0110] In some embodiments, when the brake pedal opening is equal to 0, the torque control mode is a coasting mode; when the brake pedal opening is less than or equal to a set threshold, the torque control mode is an adaptive mode; when the brake pedal opening is greater than the set threshold, the torque control mode is a braking mode.

[0111] In some embodiments, the torque control mode includes a coasting mode, when in the coasting mode, the desired electric brake torque of the vehicle is equal to a coasting energy recovery torque, and the desired mechanical brake torque is 0.

[0112] In some embodiments, the torque control mode includes an adaptive mode, when in the adaptive mode, when the coasting energy recovery torque is not limited when the vehicle is coasting, the desired electric brake torque is equal to the coasting energy recovery torque before entering the adaptive mode, and the desired mechanical brake torque is 0.

[0113] In some embodiments, the torque control mode includes an adaptive mode, when in the adaptive mode, when the coasting energy recovery torque is limited or the electric brake torque does not meet a desired deceleration when the vehicle is coasting, an actual electric brake torque that can be provided is determined according to a power system limited torque; a desired mechanical brake torque is determined according to a desired total brake torque and the actual electric brake torque that can be provided.

[0114] In some embodiments, when the vehicle is switched from the coasting mode to the adaptive mode and then to the braking mode, the mechanical brake torque increases from 0 to a desired mechanical brake torque at a set slope; when the vehicle is switched from the braking mode to the adaptive mode and then to the coasting mode, the mechanical brake torque decreases from the desired mechanical brake torque to 0 at the set slope.

[0115] In some embodiments, the set slope is calculated by:

[0116] K = (T0-T1) / P1

[0117] In the formula, K is a set slope; T0 is an expected total braking torque calculated according to an expected deceleration when the power system is not limited and the vehicle control system does not limit energy recovery; T1 is an actual electric braking torque that can be provided calculated when the power system is limited or the vehicle control system limits energy recovery; P1 is a set brake pedal opening threshold.

[0118] In some technical solutions, the torque control mode includes a braking mode, when in the braking mode, an expected electric braking torque of the vehicle is equal to a maximum electric braking torque that can be currently provided by the vehicle; and an expected mechanical braking torque is equal to a difference between the expected total braking torque and the maximum electric braking torque.

[0119] In some technical solutions, the method for calculating the expected total braking torque includes:

[0120] determining an expected deceleration according to a brake pedal opening and a braking intensity;

[0121] determining an expected braking resistance of the vehicle according to the expected deceleration;

[0122] determining the expected total braking torque according to the expected braking resistance of the vehicle.

[0123] The contents not described in detail in the specification belong to the prior art known to those skilled in the art.

Claims

1. An energy recovery control method, characterized in that, include: The current torque control mode is determined based on the brake pedal opening. The desired electric braking torque and / or desired mechanical braking torque of the vehicle are determined based on the current torque control mode. The vehicle's electric motor and / or mechanical braking system are controlled according to the desired electric braking torque and / or desired mechanical braking torque, respectively.

2. The energy recovery control method as described in claim 1, characterized in that, Methods for determining the current torque control mode include: When the brake pedal opening is 0, the torque control mode is coasting mode; When the brake pedal opening is less than or equal to the set threshold, the torque control mode is adaptive. When the brake pedal opening is greater than the set threshold, the torque control mode is braking mode.

3. The energy recovery control method as described in claim 1 or 2, characterized in that, The torque control mode includes a coasting mode. When in coasting mode, the vehicle's desired electric braking torque is equal to the coasting energy recovery torque, and the desired mechanical braking torque is 0.

4. The energy recovery control method as described in claim 1 or 2, characterized in that, The torque control mode includes an adaptive mode. When in adaptive mode, if the coasting energy recovery torque is not limited during vehicle coasting, the desired electric braking torque is equal to the coasting energy recovery torque before entering adaptive mode, and the desired mechanical braking torque is 0.

5. The energy recovery control method as described in claim 1 or 2, characterized in that, The torque control mode includes an adaptive mode. When in adaptive mode, if the coasting energy recovery torque is limited or the electric braking torque does not meet the desired deceleration during vehicle coasting, the actual electric braking torque that can be provided is determined based on the power system's limited torque; the desired mechanical braking torque is determined based on the desired total braking torque and the actual electric braking torque that can be provided.

6. The energy recovery control method as described in claim 2, characterized in that, When the vehicle switches from coasting mode to adaptive mode and then to braking mode in sequence, the mechanical braking torque increases from 0 to the desired mechanical braking torque at a set slope; when the vehicle switches from braking mode to adaptive mode and then to coasting mode in sequence, the mechanical braking torque decreases from the desired mechanical braking torque to 0 at a set slope.

7. The energy recovery control method as described in claim 6, characterized in that, The method for calculating the set slope includes: K = (T0 - T1) / P1 In the formula, K is the set slope; T0 is the expected total braking torque calculated based on the expected deceleration when the power system is not restricted and the vehicle control system does not restrict energy recovery; T1 is the actual electric braking torque that can be provided when the power system is restricted or the vehicle control system restricts energy recovery; P1 is the set brake pedal opening threshold.

8. The energy recovery control method as described in claim 1 or 2, characterized in that, The torque control mode includes a braking mode. When in braking mode, the vehicle's desired electric braking torque is equal to the maximum electric braking torque currently available from the vehicle; the desired mechanical braking torque is equal to the difference between the desired total braking torque and the maximum electric braking torque.

9. The energy recovery control method as described in claim 8, characterized in that, The method for calculating the desired total braking torque includes: Determine the desired deceleration based on the brake pedal opening and braking intensity; The desired braking resistance of the vehicle is determined based on the desired deceleration. The desired total braking torque is determined based on the vehicle's desired braking resistance.

10. An energy recovery control system as described in claim 1, characterized in that, include: Mode determination module: used to determine the current torque control mode based on the brake pedal opening; Torque distribution module: used to determine the vehicle's desired electric braking torque and / or desired mechanical braking torque based on the current torque control mode; Control module: used to control the vehicle's motor and mechanical braking system according to the desired electric braking torque and / or desired mechanical braking torque, respectively.

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