Auxiliary electronic braking method and system for an electric bicycle

Abstract

The application provides an auxiliary electronic braking method and system of an electric bicycle, comprising: detecting whether a brake lever switch is closed; if yes, the electric bicycle enters a braking state; detecting a front wheel rotating speed and a rear wheel rotating speed, and calculating a rotating speed difference according to the front wheel rotating speed and the rear wheel rotating speed; comparing the rotating speed difference with a limit rotating speed difference of skidding and a rotating speed difference of early warning skidding, and controlling energy recovery current limiting and duty cycle according to a comparison result; when braking force is unevenly distributed, the rotating speed difference of two wheels during braking is controlled by adjusting power output of a motor, so that vehicle stability during braking is realized and skidding is prevented.

Description

Technical Field

[0001] This invention relates to the field of control technology for electric bicycles, and in particular to auxiliary electronic braking methods and systems for electric bicycles. Background Technology

[0002] A car's ABS system applies intermittent braking to the locked wheel when the front and rear wheels slip due to a large speed difference. In contrast, an electric bicycle's rear wheel has a hub motor, which can function as a power generator for outputting power or as a generator for energy recovery, thus producing a braking effect.

[0003] Traditional electric bicycles use mechanical braking force for the front wheel and a combination of mechanical braking force and electric braking force for the rear wheel. When braking, the braking force is unbalanced, which can lead to slippage. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide an auxiliary electronic braking method and system for electric bicycles, which, when the braking force is unevenly distributed, controls the speed difference between the two wheels during braking by adjusting the power output of the motor, thereby stabilizing the vehicle during braking and preventing slippage.

[0005] In a first aspect, embodiments of the present invention provide an auxiliary electronic braking method for an electric bicycle, the method comprising:

[0006] Check if the brake lever switch is closed;

[0007] If so, the electric bicycle enters the braking state;

[0008] The speed of the front wheel and the speed of the rear wheel are detected, and the speed difference is calculated based on the speed of the front wheel and the speed of the rear wheel;

[0009] The speed difference is compared with the speed difference at which slippage occurs and the speed difference at which slippage is warned. Based on the comparison results, the energy recovery current limit and duty cycle are controlled.

[0010] Furthermore, the speed difference is compared with the slippage limit speed difference and the slippage warning speed difference, and the energy recovery current limit and duty cycle are controlled according to the comparison result, including:

[0011] When the front wheel speed is less than the rear wheel speed, if the speed difference is greater than 0 and less than or equal to the speed difference for warning slippage, the energy recovery current limit of the controller increases with the speed difference;

[0012] If the speed difference is greater than the speed difference for warning slippage and less than or equal to the speed difference for slippage, then the energy recovery current limit of the controller reaches the maximum current limit, and the duty cycle of the three-phase short circuit increases with the speed difference.

[0013] If the speed difference is greater than the slippage limit speed difference, the duty cycle of the three-phase short circuit of the controller reaches its maximum.

[0014] Furthermore, the speed difference is compared with the slippage limit speed difference and the slippage warning speed difference, and the energy recovery current limit and duty cycle are controlled according to the comparison result, including:

[0015] When the front wheel speed is greater than the rear wheel speed, if the speed difference is greater than 0 and less than or equal to the speed difference for warning slippage, the energy recovery current limit of the controller decreases with the speed difference;

[0016] If the speed difference is greater than the speed difference for warning slippage and less than or equal to the speed difference for slippage limit, then the duty cycle of the controller's forward drive increases with the speed difference.

[0017] If the speed difference is greater than the slippage limit speed difference, the duty cycle of the controller's forward drive reaches its maximum.

[0018] Furthermore, calculating the speed difference based on the front wheel speed and the rear wheel speed includes:

[0019] The speed difference is calculated using the following formula:

[0020]

[0021] Where σ is the speed difference, r 前轮 Let r be the front wheel speed. 后轮 The speed of the rear wheel is given.

[0022] Furthermore, the electric bicycle includes a Hall sensor, a controller, a frame, and a front wheel. The Hall sensor is fixed to the frame, and the magnetic plate is fixed to the front wheel. Detecting the front wheel speed and the rear wheel speed includes:

[0023] When the front wheel rotates and sweeps across the magnetic sheet once, the Hall sensor emits a pulse signal;

[0024] The pulse signal is transmitted to the controller, which determines the front wheel speed based on the pulse signal.

[0025] Furthermore, the electric bicycle includes a motor, wherein three Hall sensors are installed on the stator inside the motor, and magnets are installed on the rotor; detecting the front wheel speed and the rear wheel speed includes:

[0026] The speed of change of the signal is collected by the Hall sensor when the motor rotates;

[0027] The rear wheel speed is determined based on the change speed.

[0028] Secondly, embodiments of the present invention provide an auxiliary electronic braking system for an electric bicycle, the system comprising:

[0029] The detection module is used to detect whether the brake lever switch is closed;

[0030] A braking module is used to put the electric bicycle into a braking state when the brake lever switch is closed.

[0031] The calculation module is used to detect the front wheel speed and the rear wheel speed, and calculate the speed difference based on the front wheel speed and the rear wheel speed;

[0032] The comparison module is used to compare the speed difference with the slippage limit speed difference and the slippage warning speed difference, and control the energy recovery current limit and duty cycle based on the comparison result.

[0033] Furthermore, the comparison module is specifically used for:

[0034] When the front wheel speed is less than the rear wheel speed, if the speed difference is greater than 0 and less than or equal to the speed difference for warning slippage, the energy recovery current limit of the controller increases with the speed difference;

[0035] If the speed difference is greater than the speed difference for warning slippage and less than or equal to the speed difference for slippage, then the energy recovery current limit of the controller reaches the maximum current limit, and the duty cycle of the three-phase short circuit increases with the speed difference.

[0036] If the speed difference is greater than the slippage limit speed difference, the duty cycle of the three-phase short circuit of the controller reaches its maximum.

[0037] Thirdly, embodiments of the present invention provide an electronic device, including a memory and a processor, wherein the memory stores a computer program that can run on the processor, and the processor executes the computer program to implement the method described above.

[0038] Fourthly, embodiments of the present invention provide a computer-readable medium having processor-executable non-volatile program code that causes the processor to perform the method described above.

[0039] This invention provides an auxiliary electronic braking method and system for electric bicycles, including: detecting whether the brake lever switch is closed; if so, the electric bicycle enters a braking state; detecting the front wheel speed and the rear wheel speed, and calculating the speed difference based on the front wheel speed and the rear wheel speed; comparing the speed difference with the slippage limit speed difference and the slippage warning speed difference, and controlling the energy recovery current limit and duty cycle based on the comparison result; when the braking force distribution is uneven, controlling the speed difference between the two wheels during braking by adjusting the power output of the motor, thereby stabilizing the vehicle during braking and preventing slippage.

[0040] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained in accordance with the structures particularly pointed out in the description, claims and drawings.

[0041] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0042] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0043] Figure 1 A flowchart of an auxiliary electronic braking method for an electric bicycle provided in Embodiment 1 of the present invention;

[0044] Figure 2 This is a schematic diagram of the architecture of the auxiliary electronic braking system for an electric bicycle provided in Embodiment 1 of the present invention;

[0045] Figure 3 This is a schematic diagram of the auxiliary electronic braking system for an electric bicycle provided in Embodiment 2 of the present invention. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] To facilitate understanding of this embodiment, the embodiments of the present invention will be described in detail below.

[0048] Example 1:

[0049] Figure 1 This is a flowchart of an auxiliary electronic braking method for an electric bicycle provided in Embodiment 1 of the present invention.

[0050] Reference Figure 1 The method includes the following steps:

[0051] Step S101: Check whether the brake lever switch is closed;

[0052] Step S102: If yes, the electric bicycle enters the braking state;

[0053] Here, the controller determines whether it is in braking mode by detecting the brake lever switch signal; when the brake lever switch is closed and braking mode is entered, the speed difference calculation begins. In braking mode, the brake lever switch is open, and braking mode is released.

[0054] Step S103: Detect the front wheel speed and the rear wheel speed, and calculate the speed difference based on the front wheel speed and the rear wheel speed;

[0055] Step S104: Compare the speed difference σ with the slippage limit speed difference σ ref2 The speed difference σ between the warning slippage and the speed difference ref1 The comparison is made, and the energy recovery current limit and duty cycle are controlled based on the comparison results.

[0056] Furthermore, step S104 includes the following steps:

[0057] Step S201: When the front wheel speed is less than the rear wheel speed, if the speed difference is greater than 0 and less than or equal to the speed difference for warning slippage (0 < σ ≤ σ), ref1 If the controller's energy recovery current limit increases with the speed difference, then...

[0058] Specifically, when 0<σ≤σ ref1 When σ = 0, the controller enhances the energy recovery current limit to strengthen the energy recovery intensity, thereby increasing the electric braking force on the rear wheels to prevent the speed difference from continuing to increase. The greater the speed difference, the greater the energy recovery current limit. That is, when σ = 0, the controller's energy recovery current limit is I (same as the traditional controller state, depending on the overall vehicle modulation). ref1 At that time, the controller's energy recovery current limit is the maximum current limit supported by the hardware.

[0059] Step S202: If the speed difference is greater than the speed difference for warning slippage and less than or equal to the slippage limit speed difference (σ) ref1 <σ≤σ ref2If the controller's energy recovery current limit reaches the maximum current limit, the duty cycle of the three-phase short circuit increases with the speed difference.

[0060] Specifically, when σ ref1 <σ≤σ ref2 At this point, the controller increases the energy recovery current limit to the maximum, but the speed difference still exceeds the first limit. This indicates that the front wheel mechanical braking intensity is too high. The controller will then maintain the original maximum energy recovery current limit and control the motor's three-phase lines to perform periodic three-phase short circuits to prevent the speed difference from increasing further. The larger the speed difference, the higher the duty cycle of the three-phase short circuit. Specifically, when σ = σ... ref1 When σ ≥ σ, the duty cycle is 0; when σ ≥ σ ref2 At that time, the duty cycle is 1.

[0061] In step S203, if the speed difference is greater than the slippage limit speed difference, the duty cycle of the controller's three-phase short circuit reaches its maximum.

[0062] Furthermore, step S104 includes the following steps:

[0063] Step S301: When the front wheel speed is greater than the rear wheel speed, if the speed difference is greater than 0 and less than or equal to the speed difference for warning slippage, the energy recovery current limit of the controller decreases with the speed difference.

[0064] Specifically, when 0<σ≤σ ref1 When σ = 0, the controller reduces the energy recovery current limit to decrease the energy recovery intensity, thereby reducing the electric braking force on the rear wheels to prevent the speed difference from continuing to increase. The larger the speed difference, the smaller the energy recovery current limit. That is, when σ = 0, the controller's energy recovery current limit is I (same as the traditional controller state, depending on the overall vehicle modulation). ref1 At that time, the controller's energy recovery current limit is 0.

[0065] Step S302: If the speed difference is greater than the speed difference for warning slippage and less than or equal to the limit speed difference for slippage, then the duty cycle of the controller's positive drive increases with the speed difference.

[0066] In step S303, if the speed difference is greater than the slippage limit speed difference, the duty cycle of the controller's forward drive reaches its maximum.

[0067] Specifically, when σ ref1 <σ≤σ ref2At this point, the controller reduces the energy recovery current limit, lowering the energy recovery intensity to zero, but the speed difference still exceeds the first limit. This indicates that the rear wheel mechanical braking intensity is too high. The controller will then control the motor to output periodic forward rotational power to overcome the mechanical braking intensity and maintain periodic forward rotation. The current limit for forward drive is the controller's maximum current limit to prevent the speed difference from continuing to increase. The larger the speed difference, the higher the duty cycle of the forward rotation control, i.e., when σ = σ ref1 When σ ≥ σ, the duty cycle is 0; when σ ≥ σ ref2 At that time, the duty cycle is 1.

[0068] Furthermore, step S103 includes:

[0069] Calculate the speed difference according to formula (1):

[0070]

[0071] Where σ is the speed difference, r 前轮 r is the front wheel speed. 后轮 This refers to the rear wheel speed.

[0072] Furthermore, the electric bicycle includes a Hall sensor, a controller, a frame, and a front wheel. The Hall sensor is fixed to the frame, and the magnetic plate is fixed to the front wheel. Step S103 includes the following steps:

[0073] Step S401: When the current wheel rotates and sweeps across the magnetic sheet once, the Hall sensor emits a pulse signal;

[0074] In step S402, the pulse signal is transmitted to the controller, and the controller determines the front wheel speed based on the pulse signal.

[0075] Furthermore, refer to Figure 2 The electric bicycle includes a motor, with three Hall sensors installed on the stator inside the motor and magnets installed on the rotor. The motor is a hub motor. Step S103 includes the following steps:

[0076] Step S501: When the motor rotates, the speed of signal change is collected by the Hall sensor;

[0077] Step S502: Determine the rear wheel speed based on the change speed.

[0078] Here, both the front and rear wheels of the electric bicycle are equipped with mechanical brakes. Squeezing the left brake lever mechanically brakes the rear wheel, and squeezing the right brake lever mechanically brakes the front wheel. In contrast, when a traditional electric bicycle's brake lever is squeezed, the lever also transmits a switch signal to the controller, which then electrically brakes the rear wheel motor.

[0079] Example 2:

[0080] Figure 3This is a schematic diagram of the auxiliary electronic braking system for an electric bicycle provided in Embodiment 2 of the present invention.

[0081] Reference Figure 3 The system includes:

[0082] The detection module is used to detect whether the brake lever switch is closed;

[0083] The braking module is used to put the electric bicycle into a braking state when the brake lever switch is closed.

[0084] The calculation module is used to detect the front wheel speed and the rear wheel speed, and calculate the speed difference based on the front wheel speed and the rear wheel speed;

[0085] The comparison module is used to compare the speed difference with the slippage limit speed difference and the slippage warning speed difference, and control the energy recovery current limit and duty cycle based on the comparison results.

[0086] Furthermore, the comparison module is specifically used for:

[0087] If the speed difference between the front wheels and the rear wheels is greater than 0 and less than or equal to the speed difference for warning slippage, the energy recovery current limit of the controller increases with the speed difference.

[0088] If the speed difference is greater than the speed difference for warning slippage but less than or equal to the speed difference for slippage, the controller's energy recovery current limit reaches the maximum current limit, and the duty cycle of the three-phase short circuit increases with the speed difference.

[0089] If the speed difference is greater than the slippage limit speed difference, the duty cycle of the three-phase short circuit in the controller reaches its maximum.

[0090] This invention provides an auxiliary electronic braking method and system for electric bicycles, including: detecting whether the brake lever switch is closed; if so, the electric bicycle enters a braking state; detecting the front wheel speed and the rear wheel speed, and calculating the speed difference based on the front wheel speed and the rear wheel speed; comparing the speed difference with the slippage limit speed difference and the slippage warning speed difference, and controlling the energy recovery current limit and duty cycle based on the comparison result; when the braking force distribution is uneven, controlling the speed difference between the two wheels during braking by adjusting the power output of the motor, thereby stabilizing the vehicle during braking and preventing slippage.

[0091] This invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the auxiliary electronic braking method for an electric bicycle provided in the above embodiments.

[0092] This invention also provides a computer-readable medium having processor-executable non-volatile program code, on which a computer program is stored, and which, when run by a processor, executes the steps of the auxiliary electronic braking method for an electric bicycle described above.

[0093] The computer program product provided in this embodiment of the invention includes a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the methods described in the preceding method embodiments. For specific implementation details, please refer to the method embodiments, which will not be repeated here.

[0094] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the system and apparatus described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0095] Furthermore, in the description of the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.

[0096] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, essentially, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0097] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0098] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of protection of the claims.

Claims

1. An auxiliary electronic braking method for an electric bicycle, characterized in that, The method includes: Check if the brake lever switch is closed; If so, the electric bicycle enters the braking state; The speed of the front wheel and the speed of the rear wheel are detected, and the speed difference is calculated based on the speed of the front wheel and the speed of the rear wheel; The speed difference is compared with the slippage limit speed difference and the slippage warning speed difference, and the energy recovery current limit and duty cycle are controlled according to the comparison result; The speed difference is compared with the slippage limit speed difference and the slippage warning speed difference. Based on the comparison result, the energy recovery current limit and duty cycle are controlled, including: When the front wheel speed is less than the rear wheel speed, if the speed difference is greater than 0 and less than or equal to the speed difference for warning slippage, the energy recovery current limit of the controller increases with the speed difference; If the speed difference is greater than the speed difference for warning slippage and less than or equal to the speed difference for slippage, then the energy recovery current limit of the controller reaches the maximum current limit, and the duty cycle of the three-phase short circuit increases with the speed difference. If the speed difference is greater than the slippage limit speed difference, the duty cycle of the three-phase short circuit of the controller reaches its maximum.

2. The auxiliary electronic braking method for an electric bicycle according to claim 1, characterized in that, The speed difference is compared with the slippage limit speed difference and the slippage warning speed difference. Based on the comparison result, the energy recovery current limit and duty cycle are controlled, including: When the front wheel speed is greater than the rear wheel speed, if the speed difference is greater than 0 and less than or equal to the speed difference for warning slippage, the energy recovery current limit of the controller decreases with the speed difference; If the speed difference is greater than the speed difference for warning slippage and less than or equal to the speed difference for slippage limit, then the duty cycle of the controller's forward drive increases with the speed difference. If the speed difference is greater than the slippage limit speed difference, the duty cycle of the controller's forward drive reaches its maximum.

3. The auxiliary electronic braking method for an electric bicycle according to claim 1, characterized in that, Calculating the speed difference based on the front wheel speed and the rear wheel speed includes: The speed difference is calculated using the following formula: in, The speed difference, The front wheel speed, The speed of the rear wheel is given.

4. The auxiliary electronic braking method for an electric bicycle according to claim 1, characterized in that, The electric bicycle includes a Hall sensor, a controller, a frame, and a front wheel. The Hall sensor is fixed to the frame, and the magnetic plate is fixed to the front wheel. Detecting the front wheel speed and the rear wheel speed includes: When the front wheel rotates and sweeps across the magnetic sheet once, the Hall sensor emits a pulse signal; The pulse signal is transmitted to the controller, which determines the front wheel speed based on the pulse signal.

5. The auxiliary electronic braking method for an electric bicycle according to claim 1, characterized in that, The electric bicycle includes a motor, with three Hall sensors installed on the stator inside the motor and magnets installed on the rotor; the detection of the front wheel speed and the rear wheel speed includes: The speed of change of the signal is collected by the Hall sensor when the motor rotates; The rear wheel speed is determined based on the change speed.

6. An auxiliary electronic braking system for an electric bicycle, characterized in that, The system includes: The detection module is used to detect whether the brake lever switch is closed; A braking module is used to put the electric bicycle into a braking state when the brake lever switch is closed. The calculation module is used to detect the front wheel speed and the rear wheel speed, and calculate the speed difference based on the front wheel speed and the rear wheel speed; The comparison module is used to compare the speed difference with the slippage limit speed difference and the slippage warning speed difference, and control the energy recovery current limit and duty cycle according to the comparison result; The comparison module is specifically used for: When the front wheel speed is less than the rear wheel speed, if the speed difference is greater than 0 and less than or equal to the speed difference for warning slippage, the energy recovery current limit of the controller increases with the speed difference; If the speed difference is greater than the speed difference for warning slippage and less than or equal to the speed difference for slippage, then the energy recovery current limit of the controller reaches the maximum current limit, and the duty cycle of the three-phase short circuit increases with the speed difference. If the speed difference is greater than the slippage limit speed difference, the duty cycle of the three-phase short circuit of the controller reaches its maximum.

7. An electronic device comprising a memory and a processor, wherein the memory stores a computer program executable on the processor, characterized in that, When the processor executes the computer program, it implements the method described in any one of claims 1 to 5.

8. A computer-readable medium having processor-executable non-volatile program code, characterized in that, The program code causes the processor to execute the method described in any one of claims 1 to 5.

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