Intelligent braking system and braking method for new energy vehicle

Abstract

The application provides a new energy automobile intelligent braking system and a braking method, and the system comprises an electronic stability program controller ESC and an electronic booster eBKV, the electronic stability program controller ESC comprises a pump motor, a master cylinder pressure sensor and a longitudinal acceleration sensor, and the electronic booster eBKV comprises a motor and a brake pedal displacement sensor. The master cylinder pressure sensor collects the master cylinder pressure Pm, the longitudinal acceleration sensor collects the longitudinal acceleration ax, and the brake pedal displacement sensor collects the brake pedal displacement Tr. The new energy automobile intelligent braking system starts a brake autonomous enhancement BAB process through the control of the pump motor of the electronic stability program controller ESC or the motor of the electronic booster eBKV, so as to perform active pressure building and intelligent braking.

Description

Technical Field

[0001] This invention relates to the field of braking redundancy backup for new energy vehicles, specifically to an intelligent braking system and braking method for new energy vehicles. Background Technology

[0002] Insufficient braking force or more serious brake failure in automobiles typically include the following aspects:

[0003] Basic braking system malfunctions include: insufficient brake fluid reservoir, ruptured or leaking brake lines, air in brake lines, brake fluid vaporization, and excessive wear of brake discs and pads.

[0004] High-intensity, prolonged braking: Continuous braking on long downhill mountain roads or high-intensity continuous braking can lead to brake fade due to excessively high temperatures in the brake discs and pads; and

[0005] Brake controller function degradation: Functional degradation occurs when there is a fault in the eBKV (electronic booster) or ESC (electronic stability program controller).

[0006] Currently, many new energy vehicles are equipped with ESC and eBKV braking systems. How to use these two controllers to achieve mutual braking redundancy backup has become one of the research directions. Summary of the Invention

[0007] The purpose of this invention is to rely entirely on the existing sensors on the vehicle, through the signal data collected by ESC and eBKV, to promptly determine insufficient braking and braking failure, and to initiate the Brake Automatic Boost (BAB) process, which uses eBKV or ESC to actively boost braking, thereby solving the problems of insufficient braking force and braking failure.

[0008] To achieve the above objectives, the present invention provides an intelligent braking system for new energy vehicles, including an electronic stability program controller (ESC) and an electronic booster (eBKV). The ESC includes a pump motor, a master cylinder pressure sensor, and a longitudinal acceleration sensor, and the eBKV includes a motor and a brake pedal displacement sensor.

[0009] The master cylinder pressure sensor collects the master cylinder pressure Pm;

[0010] The longitudinal acceleration sensor collects the longitudinal acceleration ax;

[0011] The brake pedal displacement sensor collects the brake pedal displacement Tr;

[0012] The intelligent braking system of the new energy vehicle initiates the autonomous braking enhancement (BAB) process through the control of the pump motor of the Electronic Stability Program Controller (ESC) or the motor of the Electronic Booster (eBKV) to perform active pressure building and intelligent braking.

[0013] To achieve the above objectives, the present invention also provides an intelligent braking method for new energy vehicles, applied to the intelligent braking system of new energy vehicles as described above, the intelligent braking method for new energy vehicles comprising the following steps:

[0014] Step S1: When a signal that the brake pedal has been pressed is received, brake signal data is collected.

[0015] Step S2: Set the braking threshold value and compare the collected braking signal data with the braking threshold value to determine the braking state of the vehicle. The braking state includes normal braking, insufficient braking, and braking failure. If the vehicle is in insufficient braking or braking failure, proceed to step S3.

[0016] Step S3: Determine if the vehicle is braking on a high-friction surface. If the vehicle is braking on a high-friction surface, proceed to step S4; otherwise, return to step S1.

[0017] Step S4: Initiate the autonomous braking enhancement BAB process to perform active pressure building and intelligent braking.

[0018] In one embodiment, in step S1, the braking signal data includes master cylinder pressure Pm, longitudinal acceleration ax, and brake pedal displacement Tr.

[0019] In one embodiment, in step S1, the electronic stability program controller (ESC) and the electronic booster (eBKV) are sampled every 10 milliseconds, with a sampling frequency of 100 Hz.

[0020] In one embodiment, step S2 further includes the following steps:

[0021] Step S201: Set the braking threshold values ​​of master cylinder pressure Pm_braking deceleration ax and brake pedal displacement Tr_braking deceleration ax respectively. The braking threshold values ​​of Pm_ax and Tr_ax include the normal braking threshold value and the insufficient braking threshold value of Pm_ax, as well as the normal braking threshold value and the insufficient braking threshold value of Tr_ax.

[0022] Step S202: Determine whether Pm_ax is greater than or equal to its normal braking threshold and Tr_ax is greater than or equal to its normal braking threshold. If yes, return to step S1 to continue collecting master cylinder pressure Pm, longitudinal acceleration ax and brake pedal displacement Tr. If no, proceed to step S203.

[0023] Step S203: Determine whether Pm_ax is less than or equal to its braking insufficiency threshold and Tr_ax is less than or equal to its braking insufficiency threshold. If yes, proceed to step S204; otherwise, proceed to step S205.

[0024] In step S204, the counter N = N + 1, and proceed to step S206;

[0025] Step S205: Counter M = M + 1, and proceed to step S206; and

[0026] Step S206: Determine whether N>10 or M>20 is satisfied. If yes, confirm that the vehicle brakes are insufficient or have failed and proceed to step S3. If no, return to step S1 to continue collecting master cylinder pressure Pm, longitudinal acceleration ax, and brake pedal displacement Tr.

[0027] In one embodiment, step S3 specifically comprises:

[0028] Determine whether the vehicle has entered ABS mode. If yes, return to step S1 to continue collecting master cylinder pressure Pm, longitudinal acceleration ax, and brake pedal displacement Tr. If no, proceed to step S4.

[0029] In one embodiment, step S4 further includes the following steps:

[0030] Step S401, the instrument issues an instruction: Braking Autonomous Enhancement BAB process;

[0031] In step S402, the eBKV determines whether active boosting can be achieved. If the eBKV can achieve active boosting, proceed to step S403. If the eBKV cannot achieve active boosting, proceed to step S404.

[0032] In step S403, the eBKV performs active boost braking and proceeds to step S408;

[0033] In step S404, the instrument issues an alarm: eBKV brake assist is limited, and proceeds to step S405;

[0034] In step S405, ESC determines whether active boosting can be achieved. If ESC cannot achieve active boosting, proceed to step S407. If ESC can achieve active boosting, proceed to step S406.

[0035] In step S406, the ESC performs active boost braking and proceeds to step S408;

[0036] Step S407, the instrument issues an alarm: the ESC warning light illuminates;

[0037] Step S408: Determine whether Pm_ax is greater than or equal to its normal braking threshold and Tr_ax is greater than or equal to its normal braking threshold. If yes, proceed to step S410; otherwise, proceed to step S409.

[0038] Step S409: Determine whether the brake pedal has been released. If yes, proceed to step S414; otherwise, return to step S402.

[0039] Step S410: Determine whether the vehicle has entered ABS mode. If yes, proceed to step S411; otherwise, proceed to step S412.

[0040] Step S411: Perform strong braking of BAB, adjust the braking pressure by ESC to adjust the vehicle's slip control, and proceed to step S413.

[0041] Step S412: Perform BAB normal braking and proceed to step S413;

[0042] Step S413: Determine whether the brake pedal has been released. If yes, proceed to step S414; otherwise, return to step S410.

[0043] Step S414: Exit the BAB process.

[0044] The intelligent braking system and braking method for new energy vehicles of the present invention have the following beneficial effects:

[0045] 1. This invention makes full use of existing hardware and sensors, and matches them through software algorithms, without adding any additional costs.

[0046] 2. This invention can utilize big data on vehicle braking conditions to formulate suitable braking threshold values.

[0047] 3. The active enhanced braking BAB process of the present invention improves the driving safety of users, and can significantly improve braking efficiency, especially in the event of brake failure. Attached Figure Description

[0048] Figure 1 This is a schematic diagram of the layout of an intelligent braking system for a new energy vehicle according to an embodiment of the present invention;

[0049] Figure 2 This is a flowchart illustrating an embodiment of the intelligent braking method for new energy vehicles according to the present invention.

[0050] Figure 3 This is a graph showing the relationship between master cylinder pressure Pm and braking deceleration ax according to an embodiment of the present invention; and

[0051] Figure 4This is a graph showing the relationship between brake pedal displacement Tr and braking deceleration ax according to an embodiment of the present invention.

[0052] Figure Labels

[0053] 1. Electronic Stabilizer (ESC);

[0054] 2. Electronic booster eBKV. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0056] like Figure 1 As shown, an embodiment of the present invention provides an intelligent braking system for a new energy vehicle, which includes an electronic stability program controller (ESC1) and an electronic booster (eBKV2). The electronic stability program controller (ESC1) includes a pump motor, a master cylinder pressure sensor, and a longitudinal acceleration sensor. The electronic booster (eBKV2) includes a motor and a brake pedal displacement sensor.

[0057] The master cylinder pressure sensor collects the master cylinder pressure Pm;

[0058] The longitudinal acceleration sensor collects the longitudinal acceleration ax;

[0059] Brake pedal displacement sensor collects brake pedal displacement Tr;

[0060] The intelligent braking system of new energy vehicles initiates the autonomous braking enhancement (BAB) process through the control of the pump motor of the Electronic Stability Program Controller (ESC1) or the motor of the electronic booster (eBKV2) to perform active pressure build-up and intelligent braking. The ESC1 and eBKV2 can mutually back up redundancy, increasing vehicle braking safety.

[0061] An embodiment of the intelligent braking method for new energy vehicles according to the present invention is as follows: Figure 2 As shown, it includes the following steps:

[0062] Step S1: When a signal that the brake pedal has been pressed is received, brake signal data is collected.

[0063] Step S2: Set the braking threshold value and compare the collected braking signal data with the braking threshold value to determine the braking state of the vehicle. The braking state includes normal braking, insufficient braking, and braking failure. If the vehicle is in insufficient braking or braking failure, proceed to step S3.

[0064] Step S3: Determine if the vehicle is braking on a high-friction surface. If the vehicle is braking on a high-friction surface, proceed to step S4; otherwise, return to step S1.

[0065] Step S4: Initiate the autonomous braking enhancement BAB process to perform active pressure building and intelligent braking.

[0066] In this preferred embodiment, in step S1, the braking signal data includes master cylinder pressure Pm, longitudinal acceleration ax, and brake pedal displacement Tr.

[0067] In this preferred embodiment, in step S1, the electronic stability program controller (ESC) and the electronic booster (eBKV) are sampled once every 10 milliseconds, with a sampling frequency of 100 Hz.

[0068] In this embodiment, step S2 further includes the following steps:

[0069] Step S201: Set the braking threshold values ​​of master cylinder pressure Pm_braking deceleration ax and brake pedal displacement Tr_braking deceleration ax respectively. The braking threshold values ​​of Pm_ax and Tr_ax include the normal braking threshold value and the insufficient braking threshold value of Pm_ax, as well as the normal braking threshold value and the insufficient braking threshold value of Tr_ax.

[0070] The normal braking threshold and under-braking threshold values ​​of Pm_ax, as well as the normal braking threshold and under-braking threshold values ​​of Tr_ax, can be adjusted according to different vehicle models. In this embodiment, taking a certain vehicle model as an example, the threshold curves for normal braking and braking failure are stored in the software.

[0071] Step S202: Determine whether Pm_ax is greater than or equal to its normal braking threshold and Tr_ax is greater than or equal to its normal braking threshold. If yes, return to step S1 to continue collecting master cylinder pressure Pm, longitudinal acceleration ax and brake pedal displacement Tr. If no, proceed to step S203.

[0072] Step S203: Determine whether Pm_ax is less than or equal to its braking insufficiency threshold and Tr_ax is less than or equal to its braking insufficiency threshold. If yes, proceed to step S204; otherwise, proceed to step S205.

[0073] like Figure 3As shown, the black curve represents the thresholds of master cylinder pressure Pm and braking deceleration ax during normal braking. Each point on the curve represents the normal braking threshold value of Pm_ax. The gray curve represents the thresholds of master cylinder pressure Pm and braking deceleration ax during insufficient braking. Each point on the curve represents the insufficient braking threshold value of Pm_ax. In step S202, Pm_ax being greater than or equal to its normal braking threshold value means that at a certain master cylinder pressure Pm, the corresponding braking deceleration value ax is greater than or equal to the value corresponding to the black curve, indicating normal braking. In step S203, Pm_ax being less than or equal to its insufficient braking threshold value means that at a certain master cylinder pressure Pm, the corresponding braking deceleration value ax is less than or equal to the value corresponding to the gray curve, indicating a significant risk of insufficient braking or brake failure.

[0074] like Figure 4 As shown, the black curve represents the thresholds of brake pedal displacement Tr and braking deceleration ax during normal braking. Each point on the curve represents the normal braking threshold value of Tr_ax. The gray curve represents the thresholds of brake pedal displacement Tr and braking deceleration ax during insufficient braking. Each point on the curve represents the insufficient braking threshold value of Tr_ax. In step S202, Tr_ax is greater than or equal to its normal braking threshold value; that is, at a certain brake pedal displacement Tr, the corresponding braking deceleration value ax is greater than or equal to the value corresponding to the black curve, indicating normal braking. In step S203, Tr_ax is less than or equal to its insufficient braking threshold value; that is, at a certain brake pedal displacement Tr, the corresponding braking deceleration value ax is less than or equal to the value corresponding to the gray curve, indicating a significant risk of insufficient braking or brake failure.

[0075] It should be understood that, Figure 3 and Figure 4 The braking threshold values ​​of Pm_ax and Tr_ax shown are for illustrative purposes only and are exemplary, not restrictive. This invention can utilize large amounts of data on vehicle braking conditions to determine suitable braking threshold values.

[0076] In step S204, the counter N = N+1, and then proceed to step S206.

[0077] In step S205, the counter M = M + 1, and then proceed to step S206.

[0078] Step S206: Determine whether N>10 or M>20 is satisfied. If yes, confirm that the vehicle brakes are insufficient or have failed and proceed to step S3. If no, return to step S1 to continue collecting master cylinder pressure Pm, longitudinal acceleration ax, and brake pedal displacement Tr.

[0079] In this embodiment, step S3 specifically includes:

[0080] Determine whether the vehicle has entered ABS mode. If yes, return to step S1 to continue collecting master cylinder pressure Pm, longitudinal acceleration ax, and brake pedal displacement Tr. If no, proceed to step S4.

[0081] The Braking Auto-Enhanced (BAB) process is designed for high-friction surfaces. The purpose of determining whether the vehicle has entered ABS mode is to determine if the vehicle is braking on a high-friction surface. If the vehicle encounters icy or snowy roads, even with insufficient braking force, it is likely to enter ABS mode; in this case, there is no need to enter the Braking Auto-Enhanced (BAB) mode.

[0082] In this embodiment, step S4 further includes the following steps:

[0083] Step S401, the instrument issues an instruction: Braking Autonomous Enhancement BAB process;

[0084] In step S402, the eBKV determines whether active boosting can be achieved. If the eBKV can achieve active boosting, proceed to step S403. If the eBKV cannot achieve active boosting, proceed to step S404.

[0085] In step S403, the eBKV performs active boost braking and proceeds to step S408;

[0086] In step S404, the instrument issues an alarm: eBKV brake assist is limited, and proceeds to step S405;

[0087] In step S405, ESC determines whether active boosting can be achieved. If ESC cannot achieve active boosting, proceed to step S407. If ESC can achieve active boosting, proceed to step S406.

[0088] In step S406, the ESC performs active boost braking and proceeds to step S408;

[0089] Step S407, the instrument issues an alarm: the ESC warning light illuminates;

[0090] Step S408: Determine whether Pm_ax is greater than or equal to its normal braking threshold and Tr_ax is greater than or equal to its normal braking threshold. If yes, proceed to step S410; otherwise, proceed to step S409.

[0091] Step S409: Determine whether the brake pedal has been released. If yes, proceed to step S414; otherwise, return to step S402.

[0092] Step S410: Determine whether the vehicle has entered ABS mode. If yes, proceed to step S411; otherwise, proceed to step S412.

[0093] Step S411: Perform strong braking of BAB, adjust the braking pressure by ESC to adjust the vehicle's slip control, and proceed to step S413.

[0094] Step S412: Perform BAB normal braking and proceed to step S413;

[0095] Step S413: Determine whether the brake pedal has been released. If yes, proceed to step S414; otherwise, return to step S410.

[0096] Step S414: Exit the BAB process.

[0097] The intelligent braking system and braking method for new energy vehicles of the present invention have the following beneficial effects:

[0098] 1. This invention makes full use of existing hardware and sensors, and matches them through software algorithms, without adding any additional costs.

[0099] 2. This invention can utilize big data on vehicle braking conditions to formulate suitable braking threshold values.

[0100] 3. The active enhanced braking BAB process of the present invention improves the driving safety of users, and can significantly improve braking efficiency, especially in the event of brake failure.

[0101] Although the methods described above are illustrated and depicted as a series of actions for the sake of simplicity, it should be understood that these methods are not limited by the order of the actions, and some actions may occur in different orders and / or concurrently with other actions from the illustrations and descriptions herein or not illustrated and described herein but which may be understood by those skilled in the art.

[0102] The above embodiments are provided for those skilled in the art to implement or use the present invention. Those skilled in the art can make various modifications or changes to the above embodiments without departing from the inventive concept of the present invention. Therefore, the protection scope of the present invention is not limited to the above embodiments, but should be the maximum scope that conforms to the innovative features mentioned in the claims.

Claims

1. An intelligent braking method for new energy vehicles, characterized in that, An intelligent braking system for a new energy vehicle is disclosed. The intelligent braking system includes an Electronic Stability Program Controller (ESC) and an Electronic Booster (eBKV). The ESC includes a pump motor, a master cylinder pressure sensor, and a longitudinal acceleration sensor. The eBKV includes a motor and a brake pedal displacement sensor. The master cylinder pressure sensor collects the master cylinder pressure Pm, the longitudinal acceleration sensor collects the longitudinal acceleration ax, and the brake pedal displacement sensor collects the brake pedal displacement Tr. The intelligent braking system of the new energy vehicle initiates the autonomous braking enhancement (BAB) process through the control of the pump motor of the electronic stability program controller (ESC) or the motor of the electronic booster (eBKV) to perform active pressure building and intelligent braking. The intelligent braking method for new energy vehicles includes the following steps: Step S1: When a signal that the brake pedal has been pressed is received, brake signal data is collected. The brake signal data includes master cylinder pressure Pm, longitudinal acceleration ax, and brake pedal displacement Tr. Step S2: Set the braking threshold value and compare the collected braking signal data with the braking threshold value to determine the braking state of the vehicle. The braking state includes normal braking, insufficient braking, and braking failure. If the vehicle is in insufficient braking or braking failure, proceed to step S3. Step S3: Determine whether the vehicle is braking on a road surface with a high coefficient of friction. If the vehicle is braking on a road surface with a high coefficient of friction, proceed to step S4; otherwise, return to step S1. as well as Step S4: Initiate the autonomous braking enhancement BAB process to perform active pressure building and intelligent braking; Specifically, step S3 involves determining whether the vehicle has entered ABS mode. If so, the system returns to step S1 to continue collecting master cylinder pressure Pm, longitudinal acceleration ax, and brake pedal displacement Tr. If not, the system proceeds to step S4.

2. The intelligent braking method for new energy vehicles according to claim 1, characterized in that, In step S1, the electronic stability program controller (ESC) and the electronic booster (eBKV) are sampled every 10 milliseconds, with a sampling frequency of 100 Hz.

3. The intelligent braking method for new energy vehicles according to claim 1, characterized in that, Step S2 further includes the following steps: Step S201: Set the braking threshold values ​​for master cylinder pressure Pm_braking deceleration ax and brake pedal displacement Tr_braking deceleration ax respectively. The braking threshold values ​​for master cylinder pressure Pm_braking deceleration ax and brake pedal displacement Tr_braking deceleration ax include the normal braking threshold value and the insufficient braking threshold value for master cylinder pressure Pm_braking deceleration ax, as well as the normal braking threshold value and the insufficient braking threshold value for brake pedal displacement Tr_braking deceleration ax. Step S202: Determine whether the master cylinder pressure Pm and braking deceleration ax are greater than or equal to their normal braking threshold and the brake pedal displacement Tr and braking deceleration ax are greater than or equal to their normal braking threshold. If yes, return to step S1 to continue collecting master cylinder pressure Pm, longitudinal acceleration ax and brake pedal displacement Tr. If no, proceed to step S203. Step S203: Determine whether the master cylinder pressure Pm_braking deceleration ax is less than or equal to its insufficient braking threshold and the brake pedal displacement Tr_braking deceleration ax is less than or equal to its insufficient braking threshold. If yes, proceed to step S204; otherwise, proceed to step S205. In step S204, the counter N = N + 1, and proceed to step S206; Step S205: Counter M = M + 1, and proceed to step S206; and Step S206: Determine whether N>10 or M>20 is satisfied. If yes, confirm that the vehicle brakes are insufficient or have failed and proceed to step S3. If no, return to step S1 to continue collecting master cylinder pressure Pm, longitudinal acceleration ax, and brake pedal displacement Tr.

4. The intelligent braking method for new energy vehicles according to claim 3, characterized in that, Step S4 further includes the following steps: Step S401, the instrument issues an instruction: Braking Autonomous Enhancement BAB process; In step S402, the eBKV determines whether active boosting can be achieved. If the eBKV can achieve active boosting, proceed to step S403. If the eBKV cannot achieve active boosting, proceed to step S404. In step S403, the eBKV performs active boost braking and proceeds to step S408; In step S404, the instrument issues an alarm: eBKV brake assist is limited, and proceeds to step S405; In step S405, ESC determines whether active boosting can be achieved. If ESC cannot achieve active boosting, proceed to step S407. If ESC can achieve active boosting, proceed to step S406. In step S406, the ESC performs active boost braking and proceeds to step S408; Step S407, the instrument issues an alarm: the ESC warning light illuminates; Step S408: Determine whether Pm_ax is greater than or equal to its normal braking threshold and Tr_ax is greater than or equal to its normal braking threshold. If yes, proceed to step S410; otherwise, proceed to step S409. Step S409: Determine whether the brake pedal has been released. If yes, proceed to step S414; otherwise, return to step S402. Step S410: Determine whether the vehicle has entered ABS mode. If yes, proceed to step S411; otherwise, proceed to step S412. Step S411: Perform strong braking of BAB, adjust the braking pressure by ESC to adjust the vehicle's slip control, and proceed to step S413. Step S412: Perform BAB normal braking and proceed to step S413; Step S413: Determine whether the brake pedal has been released. If yes, proceed to step S414; otherwise, return to step S410. Step S414: Exit the BAB process.

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