New energy vehicle inching control method and system

Abstract

The application provides a new energy vehicle crawling control method and system, and belongs to the technical field of new energy vehicles. The crawling control method comprises the following steps: collecting information such as a crawling function control function switch of an audio and video entertainment system, a gear position and a fault enable of a gear control unit, a working state and four-wheel wheel speeds of an anti-lock braking system, a switch signal of a brake pedal, a working state of an electronic handbrake system and the like, and controlling the opening and closing of the crawling function; when a crawling function pre-enable flag bit is triggered, the slope value of a slope sensor is collected, and a corresponding slope value torque is preloaded when braking; when the brake pedal is released, PID fuzzy control is performed according to the comparison between the current vehicle speed and the target control vehicle speed provided by the anti-lock braking system, and the torque loading and unloading of an electric drive control unit are requested. The application realizes precise crawling control under complex road conditions and improves the driving experience of users.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new energy vehicles, in particular to a new energy vehicle inching control method and system. BACKGROUND

[0002] The statements in this section merely provide background information related to the present application and do not necessarily constitute the prior art.

[0003] With the continuous and rapid growth of the number of new energy vehicles, in order to cope with complex driving application scenarios such as hill parking, close following, and reversing into the garage, most new energy manufacturers provide inching function. After the function is triggered, the user does not need to step on the accelerator pedal, and the vehicle can stably drive at low speed, saving start-up time and improving driving safety.

[0004] The inventor found that the existing inching control system can only cope with good road environment conditions, and has insufficient applicability in complex hill starting, ice and snow road starting, and other conditions. Precise inching control under complex road conditions cannot be achieved, and there is a safety risk when blindly starting inching control. SUMMARY

[0005] In order to solve the problems of the prior art, the present application provides a new energy vehicle inching control method and system, which realizes precise inching control under complex road conditions and improves user driving experience.

[0006] In order to achieve the above purpose, the present application adopts the following technical scheme:

[0007] The present application provides a new energy vehicle inching control method in the first aspect.

[0008] A new energy vehicle inching control method includes the following processes:

[0009] Obtain the condition data required for inching pre-activation state. If at least one condition is not met, the inching function is not triggered. Otherwise, the following processes are performed:

[0010] Control the vehicle to enter the inching pre-activation state, obtain the slope value of the vehicle-mounted slope sensing element, and obtain the corresponding pre-loaded torque value according to the slope value, so that the electric drive control unit pre-loads the torque value when the vehicle brakes.

[0011] It can be understood that the above-mentioned new energy vehicle inching control method is preferably used in the vehicle controller, and can also be used in other additional controllers or existing controllers of new energy vehicles, as long as it can execute the above-mentioned inching control method to realize the inching control of new energy vehicles.

[0012] As an optional implementation, the determining whether the crawling function state is enabled comprises: when the crawling pre-activation state is enabled and the brake pedal is released, the crawling function state is enabled.

[0013] As an optional implementation, the determining whether the crawling function state is enabled comprises: when the crawling pre-activation state is enabled and the brake pedal is released, the crawling function state is enabled.

[0014] Further, the front of the vehicle is determined to be in a slip state when at least one of the following conditions is met:

[0015] (left front wheel speed-left rear wheel speed) / left front wheel speed*100%≥50%;

[0016] (right front wheel speed-right rear wheel speed) / right front wheel speed*100%≥50%;

[0017] (left front wheel speed+right front wheel speed) / 2-(left rear wheel speed+right rear wheel speed) / 2≥5.5km / h.

[0018] Further, the vehicle slip torque control comprises:

[0019] setting a target vehicle speed in D and / or R;

[0020] requesting a PID control torque according to a difference between a current vehicle speed and the target vehicle speed by using PID fuzzy control;

[0021] correcting the compensation requested torque according to a current slip rate and a lookup table result;

[0022] controlling a gradient of torque loading and unloading according to the current slip rate, motor speed and torque request to avoid new slip caused by too fast gradient change of torque loading and unloading.

[0023] Further, the vehicle non-slip torque control comprises:

[0024] setting a target vehicle speed in D and / or R;

[0025] requesting a PID control torque according to a difference between a current vehicle speed and the target vehicle speed by using PID fuzzy control;

[0026] controlling a gradient of torque loading and unloading according to the current motor speed and torque request.

[0027] As an optional implementation, during the crawling starting, accelerating or decelerating process, the motor speed of the electric drive control unit is monitored in real time, and the requested torque is corrected according to the motor speed change rate and torque request, and then executed by the electric drive control unit through real vehicle calibration.

[0028] As an optional implementation, the condition data required for the pre-activation state of the inching includes: the whole vehicle is ready; the gear is in D or R; the audio and video entertainment system inching function switch is turned on; the anti-lock braking system is not in the activated working state; the electric drive control unit has no stall, over-temperature and over-current faults; the battery management system has no discharge fault; the electronic handbrake system is released and has no communication and drive faults; the brake pedal sensor has no overvoltage, undervoltage or power supply fault; the slope sensor has no overvoltage, undervoltage or power supply fault; and the brake pedal signal triggers.

[0029] The second aspect of the present application provides a new energy vehicle inching control system.

[0030] The new energy vehicle inching control system comprises:

[0031] The inching judgment module is configured to: acquire condition data required for a pre-activation state of inching, and when at least one condition is not met, the inching function is not triggered; otherwise, the function of the inching control module is executed.

[0032] The inching control module is configured to: control the vehicle to enter the pre-activation state of inching, acquire a slope value of a vehicle-mounted slope sensing element, obtain a corresponding pre-loaded torque value according to the slope value, and enable the electric drive control unit to pre-load the torque value when the vehicle brakes.

[0033] It can be understood that the above new energy vehicle inching control system is preferably mounted on a whole vehicle controller, and can also be used for other additional controllers or existing controllers of new energy vehicles, as long as the functions of the above inching control system can be executed to realize the inching control of the new energy vehicle.

[0034] As an optional implementation, in the inching judgment module, whether the inching function state is enabled is judged, including: when the pre-activation state of inching is enabled and the brake pedal is released, the inching function state is enabled.

[0035] As an optional implementation, in the inching judgment module, whether the inching function state is enabled is judged, if not, the inching function is not triggered; otherwise, whether the vehicle is slipping is judged, when the vehicle is slipping, the vehicle slip torque control is executed, and when the vehicle is not slipping, the vehicle non-slip torque control is executed.

[0036] Further, the front is the front of the driver's seat, and when at least one of the following conditions is met, the vehicle is determined to be in a slipping state:

[0037] (left front wheel speed-left rear wheel speed) / left front wheel speed*100%≥50%;

[0038] (right front wheel speed-right rear wheel speed) / right front wheel speed*100%≥50%;

[0039] (left front wheel speed + right front wheel speed) / 2 - (left rear wheel speed + right rear wheel speed) / 2 >= 5.5 km / h.

[0040] Further, the vehicle slip torque control comprises:

[0041] setting a target vehicle speed in D and / or R gears;

[0042] adopting PID fuzzy control to request PID control torque according to the difference between the current vehicle speed and the target vehicle speed;

[0043] looking up a table according to the current slip rate and correcting the compensation request torque according to the table lookup result;

[0044] controlling the gradient of torque loading and unloading according to the current slip rate, motor speed and torque request to avoid new slip caused by too fast gradient speed change of torque loading and unloading.

[0045] Further, the vehicle slip torque control comprises:

[0046] setting a target vehicle speed in D and / or R gears;

[0047] adopting PID fuzzy control to request PID control torque according to the difference between the current vehicle speed and the target vehicle speed;

[0048] controlling the gradient of torque loading and unloading according to the current motor speed and torque request.

[0049] As an optional implementation mode, during the process of crawling start, acceleration or deceleration, the motor speed of the electric drive control unit is monitored in real time, and the request torque is corrected through real vehicle calibration and then executed through the electric drive control unit according to the motor speed change rate and the torque request.

[0050] As an optional implementation mode, the required condition data of the crawling pre-activation state comprises: the whole vehicle is ready; the gear is in D or R gear; the audio and video entertainment system crawling function switch is turned on; the anti-lock braking system is not in the activated working state; the electric drive control unit has no stall, over-temperature and over-current faults; the battery management system has no discharge fault; the electronic hand brake system is released and has no communication and drive faults; the brake pedal sensor has no overvoltage, undervoltage or power supply fault; the slope sensor has no overvoltage, undervoltage or power supply fault; the brake pedal signal is triggered.

[0051] The third aspect of the present application provides a new energy vehicle crawling control system.

[0052] A new energy vehicle crawling control system comprises a vehicle controller, which is connected with an audio and video entertainment system, a gear control unit, an anti-lock braking system, a brake pedal sensor element, an electronic hand brake system, an electric drive control unit, a battery management system and a slope sensor respectively.

[0053] The vehicle controller is configured to perform the steps of the new energy vehicle creeping control method of the first aspect of the application.

[0054] The fourth aspect of the application provides a computer readable storage medium having a program stored thereon, the program being executed by a processor to implement the steps of the new energy vehicle creeping control method of the first aspect of the application.

[0055] The fifth aspect of the application provides a vehicle controller comprising a memory, a processor, and a program stored in the memory and executable on the processor, the processor implementing the steps of the new energy vehicle creeping control method of the first aspect of the application when executing the program.

[0056] The sixth aspect of the application provides a new energy vehicle using the new energy vehicle creeping control method of the first aspect of the application, or comprising the new energy vehicle creeping control system of the second aspect of the application, or comprising the new energy vehicle creeping control system of the third aspect of the application, or comprising the computer readable storage medium of the fourth aspect of the application, or comprising the vehicle controller of the fifth aspect of the application.

[0057] Compared with the prior art, the application has the following beneficial effects:

[0058] 1. The new energy vehicle creeping control method and system of the application achieve precise creeping control under complex road conditions and improve user driving experience.

[0059] 2. The new energy vehicle creeping control method and system of the application monitor the slope value of the slope sensor, pre-load the response torque according to the slope value, and control the vehicle to meet the slope starting requirement.

[0060] 3. The new energy vehicle creeping control method and system of the application use a PID fuzzy control algorithm to continuously compare the current vehicle speed with the target vehicle speed, dynamically adjust the torque, and control the vehicle to travel near the target vehicle speed.

[0061] 4. The new energy vehicle creeping control method and system of the application monitor the four-wheel speed information of the anti-lock braking system, dynamically control the vehicle creeping torque, unloading or loading torque gradient according to the vehicle slip rate, and meet the creeping starting function on icy or muddy roads.

[0062] 5. The new energy vehicle creeping control method and system of the application monitor the speed of the electric drive control unit, correct the request torque in real time according to the speed change rate and the request torque, and suppress the shaking phenomenon existing in the vehicle starting, accelerating or decelerating process due to the transmission system gap.

[0063] Advantages of the additional aspects of the application will become apparent in the following description, which is given for the purpose of illustration and is not meant to limit the application. BRIEF DESCRIPTION OF DRAWINGS

[0064] The accompanying drawings, which form a part of this specification, are included to provide a further understanding of the application and are incorporated by reference herein. The embodiments illustrated in the drawings are intended to explain the aspects of the application and are not meant to limit the application.

[0065] Figure 1 A flowchart of a new energy vehicle creeping control method provided for embodiment 1 of the application.

[0066] Figure 2 A structure diagram of a new energy vehicle creeping control system provided for embodiment 3 of the application. DETAILED DESCRIPTION

[0067] The application will be further described with reference to the drawings and examples.

[0068] It should be noted that the following detailed description is merely exemplary and is intended to provide further description of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0069] It should be noted that the terms used herein are merely for the purpose of describing specific embodiments and are not intended to limit the exemplary embodiments according to the application. As used herein, the singular form is intended to include the plural form, unless the context clearly indicates otherwise, and it should be further understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of a feature, step, operation, device, component and / or combinations thereof.

[0070] The embodiments in the application and the features in the embodiments can be combined with each other without conflict.

[0071] Embodiment 1:

[0072] As shown in the figure, embodiment 1 of the application provides a new energy vehicle creeping control method, taking the creeping control of a vehicle control unit (VCU) as an example, including the following processes: Figure 1 The vehicle control unit (VCU) collects information such as the creeping function control function switch of the IHU (audio and video entertainment system), the gear position and fault enablement of the GCU (gear control unit), the working state and four-wheel speed of the ABS (anti-lock braking system), the switch signal of the brake pedal, and the working state of the EPB (electronic handbrake system), and controls the creeping function on-off enablement.

[0073]

[0074] ​Meanwhile, the VCU will collect the slope value of the slope sensor when the crawling function pre-enable flag is triggered, and pre-load the corresponding slope value torque when braking. When the brake pedal is released, the current vehicle speed and the target control vehicle speed provided by the ABS (anti-lock braking system) are compared, and the PID fuzzy control is performed to request the MCU (electric drive control unit) to load and unload the torque.

[0075] The present application can meet the crawling starting and steady driving functions under complex road conditions such as different slopes and flat road surfaces, and can also meet the crawling starting and steady speed driving functions on icy or muddy roads.

[0076] Specifically, the following contents are included:

[0077] S1: Crawl pre-activation state judgment

[0078] When the following conditions are met, the VCU (vehicle controller) controls the vehicle to enter the crawl pre-activation state, and feeds back the state to the ICM (instrument) display:

[0079] The vehicle is ready; the gear is in D or R; the IHU (audio and video entertainment system) crawl function switch is on; the ABS (anti-lock braking system) is not in the active working state; the MCU (electric drive system) has no serious faults such as stall, over-temperature, and over-current; the BMS (battery management system) has no serious discharge faults; the EPB (electronic handbrake system) is released and has no communication, drive, or other faults; the brake pedal sensor has no overvoltage, undervoltage, or power supply faults; the slope sensor has no overvoltage, undervoltage, or power supply faults; and the brake pedal signal is triggered.

[0080] S2: Crawl pre-activation state pre-load torque

[0081] When the crawl pre-activation state is enabled, the VCU (vehicle controller) collects the slope value of the slope sensor, and requests the MCU to execute the slope pre-load torque according to the slope value table (real vehicle calibration). When the brake pedal is pressed, the pre-load torque is mainly to avoid the slope from being too large and the torque response from being not timely, causing the vehicle to slide down the slope or start late.

[0082] S3: Crawl function state enablement

[0083] When the following conditions are met, the crawl function is in the enabled state:

[0084] (1) The crawl pre-activation state is enabled;

[0085] (2) The brake pedal is released.

[0086] S4: Vehicle slip state

[0087] When the following conditions are met, the VCU (vehicle controller) determines that the vehicle is in a slip state, and the torque control algorithm is calculated according to the slip state:

[0088] (left front wheel speed - left rear wheel speed) / left front wheel speed * 100% ≥ 50%;

[0089] (right front wheel speed - right rear wheel speed) / right front wheel speed * 100% ≥ 50%;

[0090] (left front wheel speed + right front wheel speed) / 2 - (left rear wheel speed + right rear wheel speed) / 2 ≥ 5.5 km / h.

[0091] It can be understood that in other embodiments, (left front wheel speed - left rear wheel speed) / left front wheel speed * 100% and (right front wheel speed - right rear wheel speed) / right front wheel speed * 100% can be used as the calculation formula of the slip rate, and once either condition is met, the calculation formula that meets the condition is selected as the current slip rate; when both conditions are met, both are selected as the slip rate, and subsequent slip rate values are respectively looked up and requested torque compensation is respectively performed, which will not be described here.

[0092] S5: Torque control algorithm when the vehicle is slipping

[0093] When the vehicle is in a slipping state, the VCU (vehicle controller) calculates the requested torque according to the following steps:

[0094] S5.1: Set the target vehicle speed in D and R gears;

[0095] S5.2: PID fuzzy control, request PID control torque according to the difference between the current vehicle speed and the target vehicle speed;

[0096] S5.3: Modify and compensate the requested torque according to the slip rate table;

[0097] S5.4: Control the gradient of torque loading and unloading according to the current slip rate, motor speed, and torque request;

[0098] S6: Torque control algorithm when the vehicle is not slipping

[0099] When the vehicle is not in a slipping state, the VCU (vehicle controller) calculates the requested torque according to the following steps:

[0100] S6.1: Set the target vehicle speed in D and R gears;

[0101] S6.2: PID fuzzy control, request PID control torque according to the difference between the current vehicle speed and the target vehicle speed;

[0102] S6.3: Control the gradient of torque loading and unloading according to the current motor speed and torque request;

[0103] S7: Crawl start, acceleration, and deceleration jitter suppression

[0104] In the process of starting, accelerating and decelerating, the VCU (vehicle controller) monitors the speed of the MCU (electric drive control system) in real time, and according to the speed change rate and torque request, the VCU (vehicle controller) requests the torque after correction through real vehicle calibration, and inputs it to the MCU (electric drive control system) for execution.

[0105] It can be understood that the new energy vehicle creeping control method described above can also be used for other additional controllers or existing controllers of new energy vehicles, as long as the creeping control method described above can be executed to realize the creeping control of the new energy vehicle.

[0106] Embodiment 2:

[0107] The embodiment 2 of the present application provides a new energy vehicle creeping control system, comprising:

[0108] The creeping judgment module is configured to acquire condition data required for the creeping pre-activation state, and when at least one condition is not met, the creeping function is not triggered, otherwise, the function of the creeping control module is executed:

[0109] The creeping control module is configured to control the vehicle to enter the creeping pre-activation state, acquire the slope value of the on-board slope sensor, and obtain the corresponding pre-loaded torque value according to the slope value, so that the electric drive control unit pre-loads the torque value when the vehicle brakes.

[0110] The creeping judgment module, specifically, comprises:

[0111] When the following conditions are met at the same time, the vehicle enters the creeping pre-activation state:

[0112] The vehicle is ready, the gear is in D or R, the IHU (audio and video entertainment system) creeping function switch is turned on, the ABS (anti-lock braking system) is not in the active working state, the MCU (electric drive system) has no serious faults such as stall, over-temperature, and over-current, the BMS (battery management system) has no serious discharge faults, the EPB (electronic handbrake system) is loosened and has no communication, driving or other faults, the brake pedal sensor has no overvoltage, undervoltage or power supply fault, the slope sensor has no overvoltage, undervoltage or power supply fault, and the brake pedal signal is triggered.

[0113] The creeping control module, specifically, comprises:

[0114] (1) Creeping pre-activation state pre-loaded torque

[0115] The creeping pre-activation state enables the collection of the slope value of the slope sensor, and according to the slope value, a table (real vehicle calibration) is looked up to make the MCU execute the slope pre-loaded torque, and the pre-loaded torque is loaded when the brake pedal is stepped on, mainly to avoid the slope from being too large and the torque response from being not timely, causing the vehicle to slide down the slope or start to lag.

[0116] (2) Crawl function state enable

[0117] The crawl function is in an enabled state when the following conditions are met:

[0118] (2-1) Crawl pre-activation state enable;

[0119] (2-2) Brake pedal is released.

[0120] (3) Vehicle slip state

[0121] The vehicle is determined to be in a slip state when at least one of the following conditions is met, and the torque control algorithm is calculated according to the slip state:

[0122] (left front wheel speed - left rear wheel speed) / left front wheel speed * 100% ≥ 50%;

[0123] (right front wheel speed - right rear wheel speed) / right front wheel speed * 100% ≥ 50%;

[0124] (left front wheel speed + right front wheel speed) / 2 - (left rear wheel speed + right rear wheel speed) / 2 ≥ 5.5 km / h.

[0125] It can be understood that in other embodiments, (left front wheel speed - left rear wheel speed) / left front wheel speed * 100% and (right front wheel speed - right rear wheel speed) / right front wheel speed * 100% can be used as the calculation formula of the slip rate, and once any one condition is met, the calculation formula that meets the condition is selected as the current slip rate; When both conditions are met, both are selected as the slip rate, and the requested torque compensation is then calculated according to the two slip rate values respectively, which will not be described here.

[0126] (4) Torque control algorithm when vehicle is slipping

[0127] When the vehicle is in a slip state, the requested torque is calculated according to the following steps:

[0128] (4-1) Set the target vehicle speed in D and R;

[0129] (4-2) PID fuzzy control, request PID control torque according to the difference between the current vehicle speed and the target vehicle speed;

[0130] (4-3) According to the slip rate table, correct and compensate the requested torque;

[0131] (4-4) According to the current slip rate, motor speed, and torque request, control the gradient of torque loading and unloading;

[0132] (5) Torque control algorithm when vehicle is not slipping

[0133] When the vehicle is not in a slip state, the requested torque is calculated according to the following steps:

[0134] (5-1) Set D, R target speed;

[0135] (5-2) PID fuzzy control, according to the difference between the current speed and the target speed, request PID control torque;

[0136] (5-3) According to the current motor speed, torque request, control the gradient of torque loading and unloading;

[0137] (6) Crawl start, acceleration, deceleration jitter suppression

[0138] During the crawl start, acceleration and deceleration process, the speed of MCU (electric drive control system) is monitored in real time, and the requested torque is corrected and executed by MCU (electric drive control system) according to the speed change rate and torque request through real vehicle calibration.

[0139] Embodiment 3

[0140] The embodiment 3 of the present application provides a new energy vehicle crawl control system, comprising: a vehicle controller, the vehicle controller is respectively connected with an audio and video entertainment system, a gear control unit, an anti-lock braking system, a brake pedal sensing element, an electronic hand brake system, an electric drive control unit, a battery management system and a slope sensor;

[0141] The vehicle controller is configured to perform the following steps:

[0142] A1: Crawl pre-activation state judgment

[0143] When the following conditions are met at the same time, the vehicle enters the crawl pre-activation state:

[0144] The vehicle is ready; the gear is in D or R; the IHU (audio and video entertainment system) crawl function switch is on; the ABS (anti-lock braking system) is not in the active working state; the MCU (electric drive system) has no serious faults such as stall, over-temperature and over-current; the BMS (battery management system) has no serious discharge fault; the EPB (electronic hand brake system) is released and has no communication, drive and other faults; the brake pedal sensor has no overvoltage, undervoltage or power supply fault; the slope sensor has no overvoltage, undervoltage or power supply fault; the brake pedal signal is triggered.

[0145] A2: Crawl pre-activation state pre-loading torque

[0146] Crawl pre-activation state enables, collects the slope value of the slope sensor, and according to the slope value, looks up the table (real vehicle calibration) to enable the MCU to execute the slope pre-loading torque; the pre-loading torque when the brake pedal is depressed, mainly to avoid the slope from being too large and the torque response not timely, causing the vehicle to slide or start delay.

[0147] A3: Crawl function state enablement

[0148] The following conditions are met, the crawl function is enabled state:

[0149] (1) Crawl pre-activation state enabled;

[0150] (2) Brake pedal is released.

[0151] A4: Vehicle slip state

[0152] The following conditions are met at least one of the vehicle is determined to be skidding state, torque control algorithm according to the slip state calculation:

[0153] (Left front wheel speed - left rear wheel speed) / left front wheel speed * 100% ≥ 50%;

[0154] (Right front wheel speed - right rear wheel speed) / right front wheel speed * 100% ≥ 50%;

[0155] (Left front wheel speed + right front wheel speed) / 2 - (left rear wheel speed + right rear wheel speed) / 2 ≥ 5.5 km / h.

[0156] It can be understood that in other embodiments, (left front wheel speed - left rear wheel speed) / left front wheel speed * 100% and (right front wheel speed - right rear wheel speed) / right front wheel speed * 100% can be used as the calculation formula of the slip rate, and once any one condition is met, the calculation formula that meets the condition is selected as the current slip rate; When both are met, both are selected as the slip rate, and the requested torque compensation is then searched according to the two slip rate values respectively, which is not described here.

[0157] A5: Torque control algorithm when the vehicle is slipping

[0158] The vehicle enters the slip state, and the requested torque is calculated according to the following steps:

[0159] A5.1: Set the target vehicle speed in D and R;

[0160] A5.2: PID fuzzy control, according to the difference between the current vehicle speed and the target vehicle speed, request PID control torque;

[0161] A5.3: According to the slip rate table, correct the compensation request torque;

[0162] A5.4: According to the current slip rate, motor speed, torque request, control the gradient of torque loading and unloading;

[0163] A6: Torque control algorithm when the vehicle is not slipping

[0164] The vehicle does not enter the slip state, and the requested torque is calculated according to the following steps:

[0165] A6.1: Set D range, R range target vehicle speed;

[0166] A6.2: PID fuzzy control, according to the difference between the current vehicle speed and the target vehicle speed, request PID control torque;

[0167] A6.3: According to the current motor speed, torque request, control the gradient of torque loading and unloading;

[0168] A7: Crawl start, acceleration, deceleration jitter suppression

[0169] During the process of crawl start, acceleration and deceleration, the speed of MCU (electric drive control system) is monitored in real time, and according to the speed change rate and torque request, the requested torque is corrected and executed by MCU (electric drive control system) through real vehicle calibration.

[0170] Embodiment 4:

[0171] Embodiment 4 of the application provides a computer readable storage medium, which stores a program, and the program is executed by a processor to realize the following steps:

[0172] B1: Crawl pre-activation state judgment

[0173] When the following conditions are met at the same time, the vehicle enters the crawl pre-activation state:

[0174] The whole vehicle is ready; the gear is in D range or R range; the IHU (audio and video entertainment system) crawl function switch is turned on; the ABS (anti-lock braking system) is not in the active working state; the MCU (electric drive system) has no serious faults such as stall, over-temperature and over-current; the BMS (battery management system) has no serious discharge fault; the EPB (electronic hand brake system) is loosened and has no communication, driving and other faults; the brake pedal sensor has no overvoltage, undervoltage or power supply fault; the slope sensor has no overvoltage, undervoltage or power supply fault; the brake pedal signal is triggered.

[0175] B2: Crawl pre-activation state pre-loading torque

[0176] Crawl pre-activation state enables, collects the slope value of the slope sensor, and according to the slope value, looks up the table (real vehicle calibration) to make the MCU execute the slope pre-loading torque; the pre-loading torque when the brake pedal is depressed, mainly to avoid the slope from being too large and the torque response from being not timely, causing the vehicle to slide down the slope or start to lag.

[0177] B3: Crawl function state enabling

[0178] When the following conditions are met, the crawl function is in the enabled state:

[0179] (1) Crawl pre-activation state is enabled;

[0180] (2) The brake pedal is loosened.

[0181] B4: Vehicle slip state

[0182] When at least one of the following conditions is met, the vehicle is determined to be in a slip state, and the torque control algorithm is calculated according to the slip state:

[0183] (left front wheel speed - left rear wheel speed) / left front wheel speed * 100% ≥ 50%;

[0184] (right front wheel speed - right rear wheel speed) / right front wheel speed * 100% ≥ 50%;

[0185] (left front wheel speed + right front wheel speed) / 2 - (left rear wheel speed + right rear wheel speed) / 2 ≥ 5.5 km / h.

[0186] It can be understood that in other embodiments, (left front wheel speed - left rear wheel speed) / left front wheel speed * 100% and (right front wheel speed - right rear wheel speed) / right front wheel speed * 100% can be used as the calculation formula of the slip rate, and once any one condition is met, the calculation formula that meets the condition is selected as the current slip rate; When both are met, both are selected as the slip rate, and the requested torque compensation is then searched according to the two slip rate values respectively, which will not be described here.

[0187] B5: Torque control algorithm when vehicle slips

[0188] When the vehicle enters the slip state, the requested torque is calculated according to the following steps:

[0189] B5.1: Set the target vehicle speed in D and R;

[0190] B5.2: PID fuzzy control, request PID control torque according to the difference between the current vehicle speed and the target vehicle speed;

[0191] B5.3: Modify the requested torque according to the slip rate table;

[0192] B5.4: Control the gradient of torque loading and unloading according to the current slip rate, motor speed and torque request;

[0193] B6: Torque control algorithm when vehicle does not slip

[0194] When the vehicle does not enter the slip state, the requested torque is calculated according to the following steps:

[0195] B6.1: Set the target vehicle speed in D and R;

[0196] B6.2: PID fuzzy control, request PID control torque according to the difference between the current vehicle speed and the target vehicle speed;

[0197] B6.3: Control the gradient of torque loading and unloading according to the current motor speed and torque request;

[0198] B7: Crawl start, acceleration, deceleration jitter suppression

[0199] During the crawl start, acceleration and deceleration process, the speed of the MCU (electric drive control system) is monitored in real time, and according to the speed change rate and torque request, the requested torque is corrected and executed by the MCU (electric drive control system) through real vehicle calibration.

[0200] Embodiment 5:

[0201] Embodiment 5 of the application provides a vehicle controller, comprising a memory, a processor and a program stored in the memory and executable on the processor, wherein the processor implements the following steps when executing the program:

[0202] C1: Crawl pre-activation state judgment

[0203] When the following conditions are met at the same time, the vehicle enters the crawl pre-activation state:

[0204] The vehicle is ready; the gear is in D or R; the IHU (audio and video entertainment system) crawl function switch is on; the ABS (anti-lock braking system) is not in the active working state; the MCU (electric drive system) has no serious faults such as stall, over-temperature, and over-current; the BMS (battery management system) has no serious discharge faults; the EPB (electronic hand brake system) is released and has no communication, drive, etc. Fault; the brake pedal sensor has no overvoltage, undervoltage or power supply fault; the slope sensor has no overvoltage, undervoltage or power supply fault; the brake pedal signal is triggered.

[0205] C2: Crawl pre-activation state pre-load torque

[0206] The crawl pre-activation state enables the collection of the slope value of the slope sensor, and according to the slope value, the MCU executes the slope pre-load torque by looking up the table (real vehicle calibration); the pre-load torque when the brake pedal is depressed, mainly to avoid the slope from being too large and the torque response from being not timely, causing the vehicle to slide or start to lag.

[0207] C3: Crawl function state enablement

[0208] When the following conditions are met, the crawl function is in an enabled state:

[0209] (1) The crawl pre-activation state is enabled;

[0210] (2) The brake pedal is released.

[0211] C4: Vehicle slip state

[0212] When at least one of the following conditions is met, the vehicle is determined to be in a slip state, and the torque control algorithm is calculated according to the slip state:

[0213] (left front wheel speed - left rear wheel speed) / left front wheel speed * 100% ≥ 50%;

[0214] (right front wheel speed - right rear wheel speed) / right front wheel speed * 100% ≥ 50%;

[0215] (left front wheel speed + right front wheel speed) / 2 - (left rear wheel speed + right rear wheel speed) / 2 ≥ 5.5 km / h.

[0216] It can be understood that in other embodiments, (left front wheel speed - left rear wheel speed) / left front wheel speed * 100% and (right front wheel speed - right rear wheel speed) / right front wheel speed * 100% can be used as the calculation formula of the slip rate, and once any one condition is met, the calculation formula that meets the condition is selected as the current slip rate; when both conditions are met, both are selected as the slip rate, and subsequent slip rate values are looked up and requested torque compensation is performed respectively, which is not repeated here.

[0217] C5: Torque control algorithm when vehicle slips

[0218] When the vehicle enters a slipping state, the requested torque is calculated according to the following steps:

[0219] C5.1: Set the target vehicle speed in D and R gears;

[0220] C5.2: PID fuzzy control, request PID control torque according to the difference between the current vehicle speed and the target vehicle speed;

[0221] C5.3: Modify and compensate the requested torque according to the slip rate table;

[0222] C5.4: Control the gradient of torque loading and unloading according to the current slip rate, motor speed, and torque request;

[0223] C6: Torque control algorithm when vehicle does not slip

[0224] When the vehicle does not enter a slipping state, the requested torque is calculated according to the following steps:

[0225] C6.1: Set the target vehicle speed in D and R gears;

[0226] C6.2: PID fuzzy control, request PID control torque according to the difference between the current vehicle speed and the target vehicle speed;

[0227] C6.3: Control the gradient of torque loading and unloading according to the current motor speed and torque request;

[0228] C7: Crawl start, acceleration, and deceleration jitter suppression

[0229] The crawling start, acceleration and deceleration process, the rotation speed of the MCU (electric drive control system) is monitored in real time, and according to the rotation speed change rate and torque request, the MCU (electric drive control system) is executed through real vehicle calibration and correction of the requested torque.

[0230] Embodiment 6:

[0231] The embodiment 6 of the present application provides a new energy vehicle, which utilizes the new energy vehicle crawling control method in the embodiment 1 of the present application, or comprises the new energy vehicle crawling control system in the embodiment 2 of the present application, or comprises the new energy vehicle crawling control system in the embodiment 3 of the present application, or comprises the computer readable storage medium in the embodiment 4 of the present application, or comprises the vehicle controller in the embodiment 5 of the present application.

[0232] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system or a computer program product. Therefore, the present application can be in the form of a hardware embodiment, a software embodiment or an embodiment combining software and hardware aspects. Moreover, the present application can be in the form of a computer program product implemented on one or more computer usable storage media (including but not limited to disk storage and optical storage, etc.) containing computer usable program code.

[0233] The present application is described with reference to flowcharts and / or block diagrams of the method, device (system) and computer program product according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of the flows and / or blocks in the flowcharts and / or block diagrams can be realized by computer program instructions. These computer program instructions can be provided to the processor of a general purpose computer, a special purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device that implements the functions specified in the flowcharts and / or block diagrams. Figure 1 The functions specified in one or more flows and / or blocks. Figure 1 The means for performing the functions specified in one or more flows and / or blocks.

[0234] These computer program instructions can also be stored in a computer readable storage medium which can guide the computer or other programmable data processing device to work in a specific way, so that the instructions stored in the computer readable storage medium produce a product including instruction means, which implements the functions specified in the flowcharts and / or block diagrams. Figure 1 The functions specified in one or more flows and / or blocks. Figure 1 The means for performing the functions specified in one or more flows and / or blocks.

[0235] These computer program instructions can also be loaded into a computer or other programmable data processing device, so that a series of operational steps are performed on the computer or other programmable data processing device to generate a computer-implemented process, thus the instructions executed on the computer or other programmable data processing device provide the function of implementing the processes specified in the flowchart Figure 1 one flow or multiple flows and / or the functions specified in the block Figure 1 one flow or multiple flows and / or the functions specified in the block

[0236] Those of ordinary skill in the art can understand that all or part of the flow of the above-mentioned embodiment method can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium. When the program is executed, it can include the flow of the above-mentioned embodiment of each method. The storage medium can be a magnetic disc, an optical disc, a read-only memory (ROM), a random access memory (RAM), and the like.

[0237] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for controlling the crawling motion of new energy vehicles, characterized in that: Includes the following processes: Obtain the condition data required for the creep pre-activation state. If at least one condition is not met, the creep function will not be triggered; otherwise, execute the following process: The vehicle is controlled to enter the crawl pre-activation state, the slope value of the on-board slope sensor is obtained, and the corresponding preloaded torque value is obtained according to the slope value, so that the electric drive control unit preloads the torque value when the vehicle brakes. The required conditions for pre-activation of crawl mode include: vehicle readiness; gear in D or R; crawl function switch on the audio-visual entertainment system; anti-lock braking system not activated; no stall, over-temperature, or over-current faults in the electric drive control unit; no discharge faults in the battery management system; electronic parking brake system released and no communication or drive faults; no overvoltage, undervoltage, or power supply faults in the brake pedal sensor; no overvoltage, undervoltage, or power supply faults in the slope sensor; and brake pedal signal triggered. The creep function is enabled when the creep pre-activation state is enabled and the brake pedal is released. Determine whether the creep function is enabled. If not, the creep function will not be triggered. Otherwise, determine whether the vehicle is slipping. If the vehicle is slipping, execute the vehicle slip torque control. If the vehicle is not slipping, execute the torque control when the vehicle is not slipping. Taking the area directly in front of the driver's seat as the front, the vehicle is considered to be in a skidding state when at least one of the following conditions is met: (Left front wheel speed - Left rear wheel speed) / Left front wheel speed * 100% ≥ 50%; (Right front wheel speed - Right rear wheel speed) / Right front wheel speed * 100% ≥ 50%; (left front wheel speed + right front wheel speed) / 2 - (left rear wheel speed + right rear wheel speed) / 2 ≥ 5.5 km / h; During creep start, acceleration, and deceleration, the vehicle controller monitors the rotational speed of the electric drive control system in real time. Based on the rotational speed change rate and torque request, the vehicle controller corrects the requested torque through actual vehicle calibration and then inputs it to the electric drive control system for execution.

2. The new energy vehicle creep control method as described in claim 1, characterized in that: Vehicle slip torque control includes: Set the target vehicle speed in D and / or R gear; PID fuzzy control is adopted, and the PID control torque is requested based on the difference between the current vehicle speed and the target vehicle speed; Based on the current slip ratio, look up the table and adjust the compensation request torque accordingly. Based on the current slip ratio, motor speed, and torque request, control the gradient of torque loading and unloading.

3. The new energy vehicle creep control method as described in claim 1, characterized in that: Torque control when the vehicle is not slipping includes: Set the target vehicle speed in D and / or R gear; PID fuzzy control is adopted, and the PID control torque is requested based on the difference between the current vehicle speed and the target vehicle speed; Based on the current motor speed and torque request, control the gradient of torque loading and unloading.

4. A crawl control system for new energy vehicles, characterized in that: include: The creep detection module is configured to: acquire the condition data required for the creep pre-activation state; if at least one condition is not met, the creep function will not be triggered; otherwise, the creep control module's function will be executed. The crawl control module is configured to: control the vehicle to enter the crawl pre-activation state, obtain the slope value of the on-board slope sensor element, and obtain the corresponding preloaded torque value based on the slope value, so that the electric drive control unit preloads the torque value when the vehicle brakes. The required conditions for pre-activation of crawl mode include: vehicle readiness; gear in D or R; crawl function switch on the audio-visual entertainment system; anti-lock braking system not activated; no stall, over-temperature, or over-current faults in the electric drive control unit; no discharge faults in the battery management system; electronic parking brake system released and no communication or drive faults; no overvoltage, undervoltage, or power supply faults in the brake pedal sensor; no overvoltage, undervoltage, or power supply faults in the slope sensor; and brake pedal signal triggered. The creep function is enabled when the creep pre-activation state is enabled and the brake pedal is released. Determine whether the creep function is enabled. If not, the creep function will not be triggered. Otherwise, determine whether the vehicle is slipping. If the vehicle is slipping, execute the vehicle slip torque control. If the vehicle is not slipping, execute the torque control when the vehicle is not slipping. Taking the area directly in front of the driver's seat as the front, the vehicle is considered to be in a skidding state when at least one of the following conditions is met: (Left front wheel speed - Left rear wheel speed) / Left front wheel speed * 100% ≥ 50%; (Right front wheel speed - Right rear wheel speed) / Right front wheel speed * 100% ≥ 50%; (left front wheel speed + right front wheel speed) / 2 - (left rear wheel speed + right rear wheel speed) / 2 ≥ 5.5 km / h; During creep start, acceleration, and deceleration, the vehicle controller monitors the rotational speed of the electric drive control system in real time. Based on the rotational speed change rate and torque request, the vehicle controller corrects the requested torque through actual vehicle calibration and then inputs it to the electric drive control system for execution.

5. The new energy vehicle crawl control system as described in claim 4, characterized in that: In the creep detection module, it is determined whether the creep function is enabled.

6. The new energy vehicle crawl control system as described in claim 5, characterized in that: Vehicle slip torque control includes: Set the target vehicle speed in D and / or R gear; PID fuzzy control is adopted, and the PID control torque is requested based on the difference between the current vehicle speed and the target vehicle speed; Based on the current slip ratio, look up the table and adjust the compensation request torque accordingly. Based on the current slip ratio, motor speed, and torque request, control the gradient of torque loading and unloading.

7. The new energy vehicle crawl control system as described in claim 5, characterized in that: Torque control when the vehicle is not slipping includes: Set the target vehicle speed in D and / or R gear; PID fuzzy control is adopted, and the PID control torque is requested based on the difference between the current vehicle speed and the target vehicle speed; Based on the current motor speed and torque request, control the gradient of torque loading and unloading.

8. A crawl control system for new energy vehicles, characterized in that: include: The vehicle controller is connected to the audio-visual entertainment system, gear position control unit, anti-lock braking system, brake pedal sensing element, electronic parking brake system, electric drive control unit, battery management system and slope sensor respectively; The vehicle controller is configured to execute the steps in the new energy vehicle creep control method according to any one of claims 1-3.

9. A computer-readable storage medium having a program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps in the new energy vehicle creep control method as described in any one of claims 1-3.

10. A vehicle controller, comprising a memory, a processor, and a program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps in the new energy vehicle creep control method as described in any one of claims 1-3.

11. A new energy vehicle, characterized in that: The method for controlling the crawling of new energy vehicles according to any one of claims 1-3; or, the method for controlling the crawling of new energy vehicles according to any one of claims 4-7; or, the method for controlling the crawling of new energy vehicles according to claim 8; or, the method for controlling the crawling of new energy vehicles according to claim 9; or, the method for controlling the vehicle according to claim 10.

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