Drift driving control method and system for an electronic limited slip differential

Abstract

The present application relates to a drift driving control method and system for an electronic limited slip differential. A drift driving control method and system for an electronic limited slip differential (e-LSD). The method and system enable drift driving by controlling the e-LSD differential when the driver intends to perform drift driving. Whether or not a drift mode condition is satisfied is determined based on a vehicle operating state of the driver and an output value reflecting a driving state of the vehicle. When the drift mode condition is satisfied, control is executed so that drift driving is performed by increasing the driving force of the outer wheel by using the electronic limited slip differential so that the vehicle is transitionally steered and then right and left wheels are simultaneously slipped while being kept.

Description

Technical Field

[0001] This disclosure generally relates to a drift driving control method and system with an electronic limited-slip differential (e-LSD), wherein the method and system are configured to enable drift driving by controlling the electronic limited-slip differential when the driver intends to drift. Background Technology

[0002] In vehicles without a limited-slip differential (LSD), when wheel slippage occurs due to reduced contact force on the inner wheel during rotation, the driving force on the outer wheel decreases due to the characteristics of the differential, resulting in understeer.

[0003] An electronic limited-slip differential (e-LSD) appropriately distributes torque to the wheels based on the direction of rotation and the amount of wheel slip, after determining the vehicle's driving status and the driver's intentions.

[0004] Therefore, when a vehicle equipped with an e-LSD is turning, the e-LSD can be controlled to improve turning stability. The control process includes identifying understeer, oversteer, etc., and applying control torque within the allowable driving force of the drive wheels, thereby limiting wheel slippage in the lateral direction and inducing neutral steering.

[0005] However, we have found that when a driver performs drift maneuvers in a rear-wheel-drive vehicle equipped with an e-LSD, the driving force exceeding the permissible driving force of the drive wheels cannot be transmitted. Therefore, drift maneuvers are restricted, and the driver's drift intentions may not be accurately reflected, which can be problematic.

[0006] The foregoing is intended only to help understand the background of this disclosure and is not intended to imply that this disclosure falls within the scope of related fields known to those skilled in the art. Summary of the Invention

[0007] Therefore, this disclosure is made in consideration of the aforementioned problems occurring in the relevant field, and the purpose of this disclosure is to provide a drift driving control method and system with an electronic limited-slip differential (e-LSD), wherein the method and system are configured to achieve drift driving by controlling the e-LSD differential when the driver intends to drift.

[0008] To achieve the above objectives, according to one aspect of this disclosure, a drift driving control method using an electronic limited-slip differential is provided. The method may include: determining, by a controller, whether drift mode conditions are met based on the driver's vehicle operation state and an output value reflecting the vehicle's driving state; and when drift mode conditions are met, controlling drift driving to be performed by the controller using the electronic limited-slip differential to increase the driving force on the outer wheel to cause oversteer and then maintaining simultaneous slippage of the right and left wheels.

[0009] Drift modes can be categorized into drift entry mode and drift hold mode. Depending on whether the conditions for a drift mode are met, the normal driving mode can be switched to drift entry mode, or a transition between drift entry mode and drift hold mode can be performed.

[0010] Drift entry mode can be entered when the drift mode conditions based on the vehicle's driving mode, steering state, brake operation state, accelerator opening degree, or the difference between the average front wheel speed and the average rear wheel speed are met.

[0011] If the drift mode conditions based on the difference between the average front wheel speed and the average rear wheel speed and the degree of accelerator opening are not met, the cancellation of the drift mode can be delayed by a predetermined time.

[0012] When the drift mode conditions based on the reverse steering state are met, the electronic limited-slip differential can be controlled to switch to drift holding mode.

[0013] When the drift mode conditions based on the degree of accelerator opening, the difference between the average front wheel speed and the average rear wheel speed, and the reverse steering state are met, the drift hold mode can be maintained.

[0014] When the drift mode conditions based on the reverse steering state are not met, it can be determined whether to enter drift mode.

[0015] The drift-in torque used to induce oversteer in the vehicle can be applied in drift-in mode using an electronic limited-slip differential. The drift-holding torque used to maintain slippage of both the right and left wheels can be applied in drift-hold mode using an e-LSD.

[0016] The drift-in torque can be determined by the vehicle speed, driving force, and accelerator engagement degree input to the electronic limited-slip differential.

[0017] The drift holding torque can be determined by the maximum value of the driving force input to the electronic limited-slip differential and the allowable driving force for rotating the outer wheel, lateral acceleration, and yaw rate error.

[0018] Drift-in torque and drift-hold torque can be applied by limiting their gradient.

[0019] The yaw damping control of the electronic limited-slip differential can be stopped in drift mode.

[0020] Drift mode can be canceled when the brakes are operated while in drift mode.

[0021] According to another aspect of this disclosure, a drift driving control system with an electronic limited-slip differential is provided. The drift driving control system may include: a determining portion that determines whether drift mode conditions are met based on the driver's vehicle operating state and output values ​​reflecting the vehicle's driving state; and a torque control portion that, when drift mode conditions are met, enables drift driving by increasing the driving force on the outer wheel via the electronic limited-slip differential to oversteer the vehicle and then maintaining simultaneous slippage of the right and left wheels.

[0022] According to this disclosure, when a driver intends to drift in a rear-wheel-drive vehicle, a control process can be executed to induce and maintain oversteer in the vehicle by means of an e-LSD to apply appropriate torque to the wheels of the vehicle, thereby driving the vehicle by correctly reflecting the driver's intention for drifting.

[0023] Furthermore, when maintaining a drift, the vehicle's right and left wheels can be kept sliding simultaneously to stably maintain the drift state. Additionally, the torque distribution in the lateral direction is adjusted according to the vehicle's lateral movement, thereby reducing the need for minute steering maneuvers by the driver.

[0024] Furthermore, vehicles equipped with e-LSD can more easily engage and maintain drift driving compared to vehicles without e-LSD. Therefore, the vehicle's performance in sporty driving can be improved. Attached Figure Description

[0025] The above and other objectives, features and other advantages of this disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, wherein:

[0026] Figure 1 This is a diagram illustrating the configuration of the e-LSD drift driving control system according to this disclosure;

[0027] Figure 2 This is a flowchart illustrating the drift driving control process of the e-LSD according to the present disclosure;

[0028] Figure 3 This is a flowchart illustrating the operation of generating drift torque according to this disclosure; and

[0029] Figure 4 This is a diagram illustrating drift driving behavior of a vehicle equipped with an e-LSD according to this disclosure. Detailed Implementation

[0030] The specific structural and functional descriptions of the embodiments disclosed herein are for illustrative purposes only. This disclosure can be implemented in many different forms without departing from its spirit and distinctive features. Therefore, the embodiments of this disclosure are disclosed for illustrative purposes only and should not be construed as limiting the disclosure.

[0031] Reference will now be made in detail to various embodiments of this disclosure, specific examples of which are illustrated in the accompanying drawings and described below, as embodiments of this disclosure can be modified in many different forms. While this disclosure will be described in conjunction with exemplary embodiments thereof, it is to be understood that this description is not intended to limit this disclosure to those exemplary embodiments. Rather, this disclosure is intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents, and other embodiments that may be included within the spirit and scope of this disclosure as defined by the appended claims.

[0032] It will be understood that although the terms “first,” “second,” etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, without departing from the teachings of this disclosure, the first element discussed below may be referred to as the second element. Similarly, the second element may also be referred to as the first element.

[0033] What will be understood is that when an element is referred to as "connected" or "attached" to another element, it can be directly connected to or attached to the other element, or an intermediate element may exist between them. Conversely, it should be understood that when an element is referred to as "directly connected" or "directly attached" to another element, there is no intermediate element. Other expressions explaining the relationship between elements, such as "between," "directly between," "adjacent to," or "directly adjacent to," should be interpreted in the same way.

[0034] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It will also be understood that the terms “comprising,” “including,” “having,” etc., when used in this specification, specify the presence of said features, integers, steps, operations, elements, components, and / or combinations thereof, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or combinations thereof.

[0035] Unless otherwise defined, all terms used herein, including technical and scientific terms, shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It will also be understood that terms such as those defined in common dictionaries shall be interpreted as having a meaning consistent with their meaning in the relevant field and in the context of this disclosure, and shall not be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0036] In the following description, exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0037] Figure 1 This is a diagram illustrating the configuration of a drift driving control system based on the electronic limited-slip differential (e-LSD) according to this disclosure.

[0038] Reference Figure 1 The drift driving control system disclosed herein is a driving control system for a rear-wheel drive vehicle equipped with an e-LSD, and includes: a controller 100 having a determination section 110 and a torque control section 120, wherein the determination section 110 determines whether drift mode conditions are met based on the driver's vehicle operation state and output values ​​reflecting the vehicle's driving state; and the torque control section 120 enables drift driving to be performed when drift mode conditions are met by increasing the driving force of the rotating outer wheel by means of the e-LSD to oversteer the vehicle and then maintain simultaneous slip of the right and left wheels.

[0039] Specifically, the determination part 110 receives Controller Area Network (CAN) signals from the vehicle and determines the vehicle's behavioral state based on the vehicle's driving mode, driver operation information, and various vehicle movement-related sensor signals.

[0040] In addition, the determination part 110 determines whether the drift mode conditions are met based on the driver's operation information, the difference between the front wheel speed and the rear wheel speed, the handling state, and the reverse steering state.

[0041] In addition, the torque control unit 120 performs traction control, handling control, and yaw damping control based on the CAN signal and the results of determining the vehicle's behavior state.

[0042] In addition, when the drift mode conditions are met and the vehicle's behavior is determined to be in drift mode, the torque control unit 120 calculates the drift torque to increase the driving force of the rotating outer wheel, and applies the drift torque to the rotating outer wheel by means of the e-LSD so that the vehicle is oversteered, thereby assisting the vehicle to enter drift mode.

[0043] Furthermore, after the vehicle enters drift mode, the drift torque for simultaneous slippage of the right and left wheels is calculated and applied to the right and left wheels with the help of e-LSD, thereby stabilizing the drift state.

[0044] As described above, when a driver in a rear-wheel-drive vehicle intends to drift, this disclosure enables drifting by applying appropriate torque to the wheels via an e-LSD to induce and maintain oversteer in the vehicle. Therefore, the vehicle can be driven by accurately reflecting the driver's intention to drift.

[0045] Figure 2 This is a flowchart illustrating the drift driving control process of the e-LSD according to the present disclosure.

[0046] Reference Figure 2 The drift driving control process according to this disclosure is a drive control method for a rear-wheel drive vehicle equipped with an e-LSD, and includes: the controller 100 determining whether drift mode conditions are met based on the driver's vehicle operation state and output values ​​reflecting the vehicle's driving state; and when the drift mode conditions are met, the controller 100 controls drift driving to be performed by increasing the driving force of the outer wheel by using the e-LSD to oversteer the vehicle and then maintaining simultaneous slippage of the right and left wheels.

[0047] For reference, the controller 100 according to the example embodiment can be implemented using an algorithm configured to control the operation of various components of the vehicle or a non-volatile memory (not shown) configured to store data regarding software instructions for reproducing the algorithm, and a processor (not shown) configured to perform the operations described below using the data stored in the memory. Here, the memory and processor can be implemented as separate chips. Alternatively, the memory and processor can be integrated using a single chip.

[0048] Subsequently, the drift mode can be categorized into drift entry mode and drift hold mode. Based on the determination of whether the drift mode conditions are met, the normal driving mode can be switched to drift entry mode, or a transition between drift entry mode and drift hold mode can be performed.

[0049] In other words, when certain conditions within the drift mode conditions are met, the normal driving mode is switched to drift entry mode. Depending on the determination of whether the specific conditions within the drift mode conditions are met, a transition from drift entry mode to drift hold mode or vice versa can occur.

[0050] In addition, in this disclosure, when drift mode conditions based on the vehicle's driving mode, steering state, brake operation state, accelerator opening degree, or the difference between the average front wheel speed and the average rear wheel speed are met, the e-LSD can be controlled to enter drift entry mode.

[0051] For example, in Figure 2 In steps S10, S20 and S30, when the vehicle's driving mode is sport mode, each of the steering wheel angle and steering angular velocity is equal to or greater than a predetermined value, the brake pedal is in the off state, and the accelerator pedal opening degree (i.e., the accelerator pedal opening degree) or the difference between the average front wheel speed and the average rear wheel speed is equal to or greater than a reference value, the drift entry mode is output in step S40.

[0052] However, if the drift mode conditions based on the difference between the average front wheel speed and the average rear wheel speed or the degree of accelerator opening are not met, the cancellation of the drift mode can be delayed by a predetermined time.

[0053] In other words, as a result of step S30, when the accelerator opening degree is less than the reference value and the difference between the average front wheel speed and the average rear wheel speed is less than the reference value, in step S80, control is performed by delaying the cancellation of the drift mode for a predetermined time, thereby assisting the vehicle to re-enter drift driving.

[0054] For example, since the cancellation of drift mode is delayed by a predetermined time, when the vehicle re-enters drift mode after stopping drift driving, as in the drift driving in Figure 8, it is advantageous to easily re-enter drift mode.

[0055] Furthermore, according to this disclosure, when the drift mode conditions based on the reverse steering state are met, the e-LSD can be controlled to switch to drift holding mode.

[0056] For example, when the state is determined to be in the reverse steering operation state based on the steering wheel state in step S50, the drift entry mode is changed to the drift hold mode.

[0057] Furthermore, according to this disclosure, when the drift mode conditions based on the degree of accelerator opening, the difference between the average front wheel speed and the average rear wheel speed, and the reverse steering state are met, the e-LSD can be controlled to maintain the drift holding mode.

[0058] For example, in the state where the mode is changed to drift holding mode in step S60, when the accelerator opening degree is equal to or greater than the reference value, the difference between the average front wheel speed and the average rear wheel speed is equal to or greater than the reference value, and a reverse steering operation is being performed, the drift driving state is maintained by maintaining the drift holding mode.

[0059] Here, when the drift mode conditions based on the reverse steering state are not met, it can be determined whether to enter the drift mode.

[0060] For example, in drift entry mode, if the state is determined not to be a reverse steering state as a result of determining the reverse steering operation state, the process can move to step S10 to re-determine whether to enter drift mode.

[0061] Figure 3 This is a flowchart illustrating the operation of generating drift torque according to this disclosure.

[0062] Reference Figure 3 This disclosure allows for the application of drift-in torque via e-LSD in drift-in mode to induce oversteer in the vehicle, and the application of drift-hold torque via e-LSD in drift-hold mode to hold the right and left wheels while slipping.

[0063] For example, when the current driving mode is drift mode and the brake pedal is not operated in step S100, the process of generating drift torque is executed.

[0064] Therefore, when the process of generating drift torque is activated in step S200, drift torque is selectively generated in the form of drift entry torque or drift holding torque according to the drift mode.

[0065] In other words, in drift-in mode, the drift-in torque is calculated and generated as in step S300. In drift-hold mode, the drift-hold torque is calculated and generated as in step S400.

[0066] Conversely, in step S100, if the current driving mode is not drift mode or the brake pedal is operated, no drift torque is generated. The generated drift torque is "0", and in step S900, the torque used for the regular e-LSD function is calculated and generated.

[0067] In other words, oversteer in the vehicle can be induced and maintained by applying drift-in torque and drift-hold torque via e-LSD, depending on the drift-in mode and drift-hold mode.

[0068] In addition, drift-in torque can be determined by the vehicle speed, driving force, and accelerator opening degree input to the e-LSD.

[0069] For example, the drift-in torque can be calculated using the following formula:

[0070] Drift entry torque = Drive torque input to e-LSD × Proportional gain of accelerator opening degree × Proportional gain of vehicle speed

[0071] Since the drift-in torque calculated in this way is applied to the vehicle's wheels by means of the e-LSD, the driving force lost by the rotation of the inner wheel is transmitted to the outer wheel, thereby generating rotation in the outer wheel.

[0072] In addition, drift holding torque can be determined by the maximum value of the driving force input to the e-LSD and the allowable driving force for rotating the outer wheel, lateral acceleration, and yaw rate error.

[0073] For example, drift holding torque can be calculated using the following formula:

[0074] Drift holding torque = maximum of the driving force input to the e-LSD and the allowable driving force for rotating the outer wheel × lateral acceleration / yaw rate / angular velocity error

[0075] Because the drift-holding torque calculated in this way is applied to the vehicle's wheels via the e-LSD, the vehicle's right and left wheels slip simultaneously to stably maintain the drift state. Furthermore, while maintaining a drift, the torque distribution to the right and left wheels is adjusted according to the vehicle's lateral behavior, thereby reducing the need for minute steering maneuvers by the driver.

[0076] Additionally, this disclosure can apply drift-in torque and drift-hold torque by limiting its gradient.

[0077] For example, when in Figure 3 In steps S300 and S400, when calculating the drift-in torque and drift-hold torque, the final drift torque is generated by applying a delay filter and gradient limiting to prevent excessive torque transition when generating the final drift torque in step S500.

[0078] Furthermore, according to this disclosure, if in Figure 3 In step S700, the yaw damping control of the e-LSD can be stopped in drift mode.

[0079] In other words, during drift driving, there is a change and transformation in the vehicle's movement in the yaw direction. Therefore, in a conventional e-LSD, due to yaw damping control, torque is generated to reduce the vehicle's yaw movement, thereby reducing the vehicle's drift.

[0080] Therefore, in this disclosure, when entering drift mode, yaw damping control is turned off, thereby preventing the vehicle's drift from being reduced by yaw damping control.

[0081] Furthermore, this disclosure can cancel the drift mode when the brake is operated in drift mode.

[0082] In other words, when the driver operates the brakes in drift mode, the drift mode is immediately canceled, thereby achieving vehicle stability.

[0083] Figure 4 This is a diagram illustrating drift driving motion of a vehicle equipped with an e-LSD according to this disclosure.

[0084] Reference Figure 4 This section will describe the vehicle's drift driving operation. First, state (a) indicates that the vehicle is driving in a straight line in Sport mode. Sport mode is the driving mode that allows switching to drift mode.

[0085] When the steering wheel is turned right by the driver's drift intention, the vehicle turns right in state (b), and the weight shifts outward relative to the rotation. For reference, in state (b), even though the steering wheel has entered a drift state for drifting, it has not yet entered drift mode.

[0086] In this situation, the traction force of the inner wheel is reduced, and wheel slippage may occur when the driving force is transmitted.

[0087] Subsequently, when the driver accelerates the vehicle by pressing the accelerator pedal all the way to 100% during vehicle rotation to drift, drift entry mode is entered and drift entry torque is calculated. The calculated drift entry torque is applied to the drive wheels via e-LSD.

[0088] Then, as in state (c), the inner and outer wheels are synchronized, and the torque that has leaked due to the rotation of the inner wheel is transmitted to the outer wheel. Excessive driving force is then transmitted to the outer wheel, and the tire loses traction and slips, thereby causing oversteer in the vehicle.

[0089] The driver then stops the oversteer by performing a counter-steering maneuver on the steering wheel and adjusts the vehicle's driving force by reducing the accelerator pedal opening to 50%. The drift entry mode is then switched to drift hold mode, and the drift hold torque is calculated.

[0090] Therefore, the calculated drift induction torque is applied to the drive wheel by means of the e-LSD, and the inner / outer wheel slip is maintained, as in states (d) and (e), thereby stably maintaining the drift state.

[0091] Therefore, when the driver reduces the driving force by operating the accelerator pedal to reduce the accelerator opening and simultaneously operating the steering wheel in the direction where the reverse steering is canceled, the oversteer decreases as in state (f). Then, the amount of drift-holding torque is gradually reduced, allowing the traction of the wheels to be restored.

[0092] Then, when the driver keeps the steering wheel in a neutral position and the accelerator is reduced to 10% or less, the drift mode is canceled as in state (g), and the vehicle can return to normal driving.

[0093] As described above, according to this disclosure, when a driver intends to drift in a rear-wheel-drive vehicle, a control process can be executed to induce and maintain oversteer in the vehicle by means of an e-LSD to apply appropriate torque to the wheels of the vehicle, thereby driving the vehicle by correctly reflecting the driver's intention to drift.

[0094] Furthermore, when maintaining a drift, the vehicle's right and left wheels can be kept sliding simultaneously to stably maintain the drift state. Additionally, the torque distribution in the lateral direction is adjusted according to the vehicle's lateral movement, thereby reducing the need for minute steering maneuvers by the driver.

[0095] Furthermore, vehicles equipped with e-LSD can more easily engage and maintain drift driving compared to vehicles without e-LSD. Therefore, the vehicle's performance in sporty driving can be improved.

[0096] Although exemplary embodiments of this disclosure have been described for illustrative purposes, those skilled in the art will recognize that various modifications, additions, and substitutions may be made without departing from the scope and spirit of this disclosure as disclosed in the appended claims.

[0097] Cross-references to related applications

[0098] This application claims priority to Korean Patent Application No. 10-2021-0179623, filed on December 15, 2021, the entire contents of which are incorporated herein by reference for all purposes.

Claims

1. A drift driving control method for an electronic limited-slip differential, the method comprising the following steps: The controller determines whether the drift mode conditions are met based on the driver's vehicle operation status or the output value reflecting the vehicle's driving status. as well as When the drift mode conditions are met, the controller controls the drift driving by increasing the driving force on the outer wheel using the electronic limited-slip differential to cause the vehicle to oversteer and then maintaining simultaneous slippage of the right and left wheels. The drift mode is categorized into drift entry mode and drift hold mode. Based on the determination of whether the drift mode conditions are met, the normal driving mode is either switched to drift entry mode or a transition between drift entry mode and drift hold mode is executed. Specifically, when the drift mode conditions based on the vehicle's driving mode, steering state, brake operation state, accelerator opening degree, or the difference between the average front wheel speed and the average rear wheel speed are met, the vehicle enters the drift entry mode. Specifically, when the drift mode conditions based on the difference between the average front wheel speed and the average rear wheel speed and the degree of accelerator opening are not met, the cancellation of the drift mode is delayed for a predetermined time.

2. The drift driving control method according to claim 1, wherein, When the drift mode conditions based on the reverse steering state are met, the electronic limited-slip differential is controlled to switch to the drift holding mode.

3. The drift driving control method according to claim 2, wherein, The drift holding mode is maintained when the drift mode conditions based on the accelerator opening degree, the difference between the average front wheel speed and the average rear wheel speed, and the reverse steering state are met.

4. The drift driving control method according to claim 2, wherein, If the drift mode conditions based on the reverse steering state are not met, determine whether to enter the drift mode.

5. The drift driving control method according to claim 1, wherein, In the drift entry mode, a drift entry torque is applied by means of the electronic limited-slip differential to induce the oversteer in the vehicle, and In the drift holding mode, a drift holding torque is applied by means of the electronic limited-slip differential to maintain the slippage of both the right and left wheels.

6. The drift driving control method according to claim 5, wherein, The drift-in torque is determined by the vehicle speed input to the electronic limited-slip differential, the driving force, and the degree of accelerator opening.

7. The drift driving control method according to claim 1, wherein, The yaw damping control of the electronic limited-slip differential is stopped in drift mode.

8. The drift driving control method according to claim 1, wherein, When the brake is operated in drift mode, the drift mode is canceled.

9. A drift driving control method for an electronic limited-slip differential, the method comprising the following steps: The controller determines whether the drift mode conditions are met based on the driver's vehicle operation status or the output value reflecting the vehicle's driving status. as well as When the drift mode conditions are met, the controller controls the drift driving by increasing the driving force on the outer wheel using the electronic limited-slip differential to cause the vehicle to oversteer and then maintaining simultaneous slippage of the right and left wheels. The drift mode is categorized into drift entry mode and drift hold mode. Based on the determination of whether the drift mode conditions are met, the normal driving mode is either switched to drift entry mode or a transition between drift entry mode and drift hold mode is executed. In the drift entry mode, a drift entry torque is applied by means of the electronic limited-slip differential to induce oversteer in the vehicle, and in the drift holding mode, a drift holding torque is applied by means of the electronic limited-slip differential to maintain the simultaneous slippage of the right and left wheels. The drift holding torque is determined by the maximum value of the driving force input to the electronic limited-slip differential and the allowable driving force of the rotating outer wheel, the lateral acceleration, and the yaw rate error.

10. A drift driving control method for an electronic limited-slip differential, the method comprising the following steps: The controller determines whether the drift mode conditions are met based on the driver's vehicle operation status or the output value reflecting the vehicle's driving status. as well as When the drift mode conditions are met, the controller controls the drift driving by increasing the driving force on the outer wheel using the electronic limited-slip differential to cause the vehicle to oversteer and then maintaining simultaneous slippage of the right and left wheels. The drift mode is categorized into drift entry mode and drift hold mode. Based on the determination of whether the drift mode conditions are met, the normal driving mode is either switched to drift entry mode or a transition between drift entry mode and drift hold mode is executed. In the drift entry mode, a drift entry torque is applied by means of the electronic limited-slip differential to induce oversteer in the vehicle, and in the drift holding mode, a drift holding torque is applied by means of the electronic limited-slip differential to maintain the simultaneous slippage of the right and left wheels. Specifically, the drift-in torque and the drift-holding torque are applied by limiting the gradient between the drift-in torque and the drift-holding torque.

11. A drift driving control system for an electronic limited-slip differential, the drift driving control system comprising: The controller has a determining part and a torque control part. The determining factor is based on the driver's vehicle operation status and the output values ​​reflecting the vehicle's driving status to determine whether the drift mode conditions are met. When the drift mode conditions are met, the torque control unit increases the driving force on the outer wheel by means of an electronic limited-slip differential to oversteer the vehicle and then maintains simultaneous slippage of the right and left wheels, thereby enabling drift driving. The drift mode is categorized into drift entry mode and drift hold mode. Based on the determination of whether the drift mode conditions are met, the normal driving mode is either switched to drift entry mode or a transition between drift entry mode and drift hold mode is executed. Specifically, when the drift mode conditions based on the vehicle's driving mode, steering state, brake operation state, accelerator opening degree, or the difference between the average front wheel speed and the average rear wheel speed are met, the vehicle enters the drift entry mode. Specifically, when the drift mode conditions based on the difference between the average front wheel speed and the average rear wheel speed and the degree of accelerator opening are not met, the cancellation of the drift mode is delayed for a predetermined time.

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