Powertrain for vehicle and brake control method thereof

Abstract

The present invention relates to a powertrain for a vehicle and a brake control method thereof. The powertrain for a vehicle may include: a motor; a planetary gear set mounted to rotate parallel to a rotation axis of the motor so that one rotating element can exchange power with the motor; a front wheel drive shaft engaged with the planetary gear set to receive power from another rotating element of the planetary gear set and transmit the rotational force to the front wheels coupled to the front wheel drive shaft; and a rear wheel drive shaft engaged with the planetary gear set and mounted to receive power from another rotating element of the planetary gear set to rotate parallel to the rotation axis of the motor and transmit the rotational force to the rear wheels coupled to the rear wheel drive shaft.

Description

Technical Field

[0001] The present invention relates to a powertrain and brake control thereof that can be used in an electric vehicle or the like. Background Art

[0002] Since the motor is installed in a hybrid vehicle or an electric vehicle, when the vehicle brakes, regenerative braking can be performed using the installed motor.

[0003] Regenerative braking is a primary means by which energy of a vehicle can be recovered and reused, thereby improving the vehicle's fuel efficiency. Therefore, it is necessary for hybrid vehicles or electric vehicles to ensure stable braking performance while maximizing regenerative braking performance.

[0004] The information included in this Background of the Invention section is only intended to enhance understanding of the general background of the invention and should not be taken as an acknowledgment or any form of suggestion that this information constitutes the prior art already known to a person skilled in the art. Summary of the Invention

[0005] Various aspects of the present invention are directed to providing a powertrain and braking control method for a vehicle that can improve regenerative braking performance to increase the energy recovery rate of the vehicle, thereby improving the fuel efficiency of the vehicle, and can ensure stable braking performance while reducing vehicle costs without installing expensive and complex devices.

[0006] The power transmission system for a vehicle according to various exemplary embodiments of the present invention for achieving this purpose is configured to include: a motor; a planetary gear set, which is installed to rotate parallel to the rotation axis of the motor so that one rotating element can exchange power with the motor; a front wheel drive shaft, which is engaged with the planetary gear set to receive power from another rotating element of the planetary gear set and transmit the rotational force to the front wheel connected to the front wheel drive shaft; and a rear wheel drive shaft, which is engaged with the planetary gear set and installed to receive power from another rotating element of the planetary gear set to rotate parallel to the rotation axis of the motor and transmit the rotational force to the rear wheel connected to the rear wheel drive shaft.

[0007] The planetary gear set may include a single pinion planetary gear set, and a rotation shaft of the motor may be connected to a planetary carrier of the planetary gear set to exchange power therebetween.

[0008] The rotation shaft of the motor may be formed of a hollow shaft, and any one of the front wheel drive shaft and the rear wheel drive shaft may be installed to penetrate the inside of the rotation shaft of the motor.

[0009] The first gear can be set on the rotating shaft of the motor, the second gear meshing with the first gear can be set on the planetary carrier of the planetary gear set, the third gear can be set on the ring gear of the planetary gear set, and the fourth gear meshing with the third gear can be set on one of the front wheel drive shaft and the rear wheel drive shaft installed as the rotating shaft passing through the motor.

[0010] The fifth gear may be provided on the sun gear of the planetary gear set, and the sixth gear meshing with the fifth gear may be provided on the other one except one of the front wheel drive shaft and the rear wheel drive shaft installed as a rotation shaft penetrating the motor.

[0011] The planetary gear set may include a double pinion planetary gear set, and the rotation shaft of the motor may be connected to a ring gear of the planetary gear set to exchange power therebetween.

[0012] The rotation shaft of the motor may be formed of a hollow shaft, and any one of the front wheel drive shaft and the rear wheel drive shaft may be installed to penetrate the inside of the rotation shaft of the motor.

[0013] The first gear may be provided on the rotating shaft of the motor, the second gear meshing with the first gear may be provided on the ring gear of the planetary gear set, the third gear may be provided on the planetary carrier of the planetary gear set, and the fourth gear meshing with the third gear may be provided on one of the front wheel drive shaft and the rear wheel drive shaft installed as the rotating shaft passing through the motor.

[0014] The fifth gear may be provided on the sun gear of the planetary gear set, and the sixth gear meshing with the fifth gear may be provided on the other one except one of the front wheel drive shaft and the rear wheel drive shaft installed as a rotation shaft penetrating the motor.

[0015] In addition, the braking control method for a vehicle according to various exemplary embodiments of the present invention for achieving this purpose is configured to include: as a braking control method for a vehicle equipped with the above-mentioned powertrain, using an ideal braking force line diagram, generating a braking torque distribution map through a controller according to the vehicle speed, the friction characteristics of the road and the maximum possible regenerative braking torque; distributing the braking torque of the front wheels and the rear wheels through the controller according to the braking torque distribution map and the required braking torque; distributing the distributed braking torque of the front wheels and the rear wheels into regenerative braking torque and friction braking torque through the controller; controlling the motor according to the regenerative braking torque through the controller, and performing friction braking using the friction braking mechanism according to the friction braking torque.

[0016] Assume that on the ideal braking force diagram, the intersection of the ideal braking force distribution line and the maximum deceleration line that the vehicle can brake by the motor is set as control point A; the intersection of the straight line connecting the control point A from the origin where the braking force of the front and rear wheels is 0 and the maximum deceleration line that the vehicle can brake by the motor based on the current vehicle speed is set as control point B; the intersection of the straight line extending from control point B with the same slope as the simple braking force distribution line of the braking device (the braking device has a constant front and rear wheel braking force distribution ratio) and the ideal braking force distribution line is set as control point B. Point C; the intersection of the simple braking force distribution line and the ideal braking force distribution line is set as control point D; the braking torque distribution map can be configured to divide the deceleration area so that the deceleration area at or below control point B is set as interval 1, the deceleration area exceeding control point B and at or below control point C is set as interval 2, the deceleration area exceeding control point C and at or below control point D is set as interval 3, and the deceleration area exceeding control point D is set as interval 4, and for each of intervals 1, 2, 3 and 4, the braking force is distributed according to different braking force distribution lines.

[0017] In interval 1, the braking force distribution line can be formed by a straight line connecting control point B from the origin where all braking forces of the front and rear wheels are 0, in interval 2, the braking force distribution line can be formed by a straight line connecting control point B to control point C, in interval 3, the braking force distribution line can be formed by a straight line connecting control point C to control point D, and in interval 4, the braking force distribution line can be formed by a straight line extending from control point D along the simple braking force distribution line.

[0018] In interval 1, the braking force distribution line can be formed by a straight line connecting control point B from the origin where all braking forces of the front and rear wheels are 0. In interval 1, if the deceleration required by the driver changes, the controller can only use the regenerative braking of the motor to meet the required deceleration.

[0019] In interval 2, the braking force distribution line can be formed by a straight line connecting control point B and control point C. In interval 2, if the deceleration required by the driver changes, the controller can be configured to control the motor so that the regenerative braking can maintain the level of control point B and only add the friction braking of the friction braking mechanism thereto to meet the required deceleration.

[0020] In interval 3, the braking force distribution line can be formed by a straight line connecting control point C and control point D. In interval 3, if the deceleration required by the driver increases, the controller can increase the friction braking of the friction braking mechanism while gradually reducing the regenerative braking of the motor to meet the required deceleration.

[0021] As the driver's desired deceleration increases throughout interval 3, the controller may linearly reduce the regenerative braking of the motor from the level of control point B to zero.

[0022] In interval 4, the braking force distribution line may be formed by a straight line extending from the control point D along the simple braking force distribution line. In interval 4, if the deceleration required by the driver increases, the controller may linearly increase the friction braking force of the friction brake mechanism as a result.

[0023] The present invention can improve regenerative braking performance to increase the energy recovery rate of a vehicle, thereby improving the fuel efficiency of the vehicle, and can avoid installing expensive and complicated devices, thereby ensuring stable braking performance even while reducing vehicle costs.

[0024] The methods and apparatus of the present invention have other features and advantages that will be apparent from or are set forth in detail in the accompanying drawings and subsequent detailed description incorporated herein, which together serve to explain the specific principles of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 are schematic diagrams illustrating various exemplary embodiments of a power train for a vehicle according to various exemplary embodiments of the present invention.

[0026] Figure 2 It shows Figure 1 Schematic diagram of the powertrain power flow shown.

[0027] Figure 3 are schematic diagrams illustrating various exemplary embodiments of a power train of a vehicle according to various exemplary embodiments of the present invention.

[0028] Figure 4 is a flowchart illustrating an exemplary embodiment of a brake control method of a vehicle according to various exemplary embodiments of the present invention.

[0029] Figure 5 is a schematic diagram illustrating a braking torque distribution map of a braking control method according to various exemplary embodiments of the present invention.

[0030] Figure 6 When using Figure 5 The illustrated braking torque distribution map according to various exemplary embodiments of the present invention is a graph summarizing changes in the regenerative braking torque of the motor and the friction braking torque of the friction braking mechanism according to an increase in the required deceleration over time when braking control is performed.

[0031] It will be appreciated that the accompanying drawings are not necessarily drawn to scale, but rather present a slightly simplified representation of the various features illustrating the basic principles of the present invention. The specific design features of the present invention as contained herein (including, for example, specific dimensions, directions, positions, and shapes) will be determined in part by the specific intended application and use environment.

[0032] In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing. DETAILED DESCRIPTION

[0033] Reference will now be made in detail to various embodiments of the present invention, examples of which are illustrated in the accompanying drawings and described below. Although the present invention will be described in conjunction with exemplary embodiments of the present invention, it will be understood that this specification is not intended to limit the present invention to those exemplary embodiments. On the other hand, the present invention is intended to cover not only the exemplary embodiments of the present invention, but also various alternative forms, modifications, equivalent forms, and other embodiments that may be included within the spirit and scope of the present invention as defined by the appended claims.

[0034] refer to Figure 1 、 Figure 2 and Figure 3 , various exemplary embodiments of the powertrain for a vehicle according to various exemplary embodiments of the present invention are commonly configured to include: a motor M, a planetary gear set PG, a front-wheel drive shaft FD, and a rear-wheel drive shaft RD, the planetary gear set PG being installed to rotate parallel to the rotation axis of the motor M so that one rotation element can exchange power with the motor M; the front-wheel drive shaft FD being installed to receive power from another rotation element of the planetary gear set PG to rotate parallel to the rotation axis of the motor M and transmit the rotational force to the front wheels coupled to the front-wheel drive shaft; the rear-wheel drive shaft RD being installed to receive power from another rotation element of the planetary gear set PG to rotate parallel to the rotation axis of the motor M and transmit the rotational force to the rear wheels coupled to the rear-wheel drive shaft.

[0035] That is, the power train is configured to connect the motor M to one rotation element of the planetary gear set PG having three rotation elements to provide power, and enable the other two rotation elements to respectively provide power to the front and rear wheels.

[0036] exist Figure 1 and Figure 2 In the various exemplary embodiments shown, the planetary gear set PG includes a single pinion planetary gear set; a rotation shaft of the motor M is connected to exchange power with a planet carrier C of the planetary gear set PG.

[0037] The rotation shaft of the motor M is formed of a hollow shaft, and any one of the front wheel drive shaft FD and the rear wheel drive shaft RD is installed so as to penetrate the inside of the rotation shaft of the motor M.

[0038] For reference, Figure 1 The configuration in which the front wheel drive shaft FD is installed to pass through the interior of the rotating shaft of the motor M is shown. Of course, the rear wheel drive shaft RD can also be configured to be installed to pass through the interior of the rotating shaft of the motor M.

[0039] The first gear G1 is set on the rotating shaft RS of the motor M, the second gear G2 meshing with the first gear G1 is set on the planetary carrier C of the planetary gear set PG, the third gear G3 is set on the ring gear R of the planetary gear set PG, and the fourth gear G4 meshing with the third gear G3 is set on one of the front wheel drive shaft FD and the rear wheel drive shaft RD installed as the rotating shaft passing through the motor M.

[0040] In addition, the fifth gear G5 is set on the sun gear S of the planetary gear set PG, where the sun gear S is installed on the intermediate shaft IS, and the sixth gear G6 meshing with the fifth gear G5 is set on the other one of the front wheel drive shaft FD and the rear wheel drive shaft RD installed as a rotating shaft passing through the motor M.

[0041] Accordingly, if Figure 2 As shown, the power input from the motor M to the planetary carrier C of the planetary gear set PG through the second gear G2 meshing with the first gear G1 is transmitted to the front wheel side through the ring gear R, the third gear G3 and the fourth gear G4, and is simultaneously transmitted to the rear wheel side through the sun gear S, the fifth gear G5 and the sixth gear G6.

[0042] For reference, in Figure 1 Unmentioned reference numeral BR denotes a bearing located between the front-wheel drive shaft FD and the rear-wheel drive shaft RD.

[0043] Furthermore, the controller CLR is configured to control the motor M, and the controller CLR is configured to control the friction brake mechanism BK mounted on each wheel to perform friction braking.

[0044] At the same time, Figure 3 In various exemplary embodiments shown, the planetary gear set PG includes a double pinion planetary gear set, and in the present case, a rotation shaft of the motor M is connected to a ring gear R of the planetary gear set PG to exchange power therebetween.

[0045] The rotation shaft of the motor M is formed of a hollow shaft, and any one of the front wheel drive shaft FD and the rear wheel drive shaft RD is installed so as to penetrate the inside of the rotation shaft of the motor M.

[0046] The first gear G1 is provided on the rotating shaft of the motor M, the second gear G2 meshing with the first gear G1 is provided on the ring gear R of the planetary gear set PG, the third gear G3 is provided on the planetary carrier C of the planetary gear set PG, and the fourth gear G4 meshing with the third gear G3 is provided on one of the front wheel drive shaft FD and the rear wheel drive shaft RD installed as the rotating shaft passing through the motor M.

[0047] In addition, the fifth gear G5 is provided on the sun gear S of the planetary gear set PG, and the sixth gear G6 meshing with the fifth gear G5 is provided on the other of the front wheel drive shaft FD and the rear wheel drive shaft RD installed as a rotating shaft passing through the motor M.

[0048] That is to say, in Figure 3 In the various exemplary embodiments shown, the planetary gear set PG is a double pinion planetary gear set, the second gear G2 meshing with the first gear G1 connected to the motor M is connected to the ring gear R, and only the third gear G3 is connected to the planet carrier C. Figure 1 The configurations of the various exemplary embodiments are different.

[0049] The powertrain of the vehicle according to the various exemplary embodiments of the present invention described above can constantly determine the speed ratio between the front-wheel drive shaft FD and the rear-wheel drive shaft RD by the transmission ratio of the planetary gear set PG, realize four-wheel drive by a simple configuration, and perform braking control according to the braking control method to be described later, thereby improving the energy recovery rate through regenerative braking even without adopting an expensive braking system, thereby improving the fuel efficiency of the vehicle.

[0050] For reference, the friction brake mechanism BK is a braking device configured to form a simple front and rear wheel braking force distribution ratio that increases at a constant slope, for example, refers to a conventional electronic stability control (ESC) device installed on a general vehicle rather than a hybrid vehicle or an electric vehicle.

[0051] A conventional hybrid vehicle or electric vehicle is equipped with a cooperative control braking system that achieves the required braking torque by appropriately combining the regenerative braking torque of the motor M and the friction braking torque of the braking device, and a conventional active hydraulic booster (AHB), integrated electric brake (IEB), etc. correspond to this cooperative control braking system, but they are more expensive than a conventional ESC device that does not have a cooperative control function.

[0052] Accordingly, even if a vehicle is not equipped with the above-mentioned AHB or IEB and is only equipped with a braking device (such as a conventional ESC device) that performs braking control according to a simple braking force distribution line (in which the braking force distribution ratio of the front wheels and the rear wheels has a constant slope), the present invention can increase the amount of regenerative braking, thereby improving fuel efficiency, and distribute the front braking torque and the rear braking torque as similar as possible to the ideal braking force distribution line, thereby also ensuring excellent braking stability of the vehicle.

[0053] refer to Figure 4 As a braking control method for a vehicle provided with the above-mentioned powertrain, the braking control method for a vehicle according to various exemplary embodiments of the present invention is configured to include: using an ideal braking force diagram, taking into account the vehicle speed, the friction characteristics of the road, and the maximum possible regenerative braking torque, generating a braking torque distribution map through the controller CLR (step S10); considering the braking torque distribution map and the required braking torque, distributing the braking torque of the front wheels and the rear wheels through the controller CLR (step S20); distributing the distributed braking torque of the front wheels and the rear wheels into regenerative braking torque and friction braking torque through the controller CLR (step S30); controlling the motor M according to the regenerative braking torque through the controller CLR, and performing friction braking using the friction braking mechanism BK according to the friction braking torque (step S40).

[0054] Here, in Figure 5 On the ideal braking force diagram shown, the intersection of the ideal braking force distribution line I and the maximum deceleration line L1 at which the vehicle can be braked by the motor M is set as control point A; the intersection B between the straight line connecting the control point A from the origin where all braking forces of the front and rear wheels are 0 and the maximum deceleration line L2 at which the vehicle can be braked by the motor M based on the current vehicle speed is set as control point B; the intersection point at which a straight line extending from control point B with the same slope as a simple braking force distribution line P of a braking device (the braking device has a constant front and rear wheel braking force distribution ratio) intersects with the ideal braking force distribution line I is set as control point C; the intersection point at which the simple braking force distribution line P intersects with the ideal braking force distribution line I is set as control point D.

[0055] At this time, the braking torque distribution map will set the deceleration area at or below control point B as interval 1, the deceleration area exceeding control point B and at or below control point C as interval 2, the deceleration area exceeding control point C and at or below control point D as interval 3, and the deceleration area exceeding control point D as interval 4, and will be configured to distribute the braking force along different braking force distribution lines for each of intervals 1, 2, 3, and 4.

[0056] That is, in interval 1, the braking force distribution line is formed by the straight line DL1 connecting the control point B from the origin where all the braking forces of the front and rear wheels are 0; in interval 2, the braking force distribution line is formed by the straight line DL2 connecting the control point B to the control point C; in interval 3, the braking force distribution line is formed by the straight line DL3 connecting the control point C to the control point D; in interval 4, the braking force distribution line is formed by the straight line DL4 extending from the control point D along the simple braking force distribution line P.

[0057] Accordingly, in intervals 1 to 4, the braking force distribution line has a different slope in each interval, but is sequentially connected to form one continuous braking force distribution line.

[0058] For reference, the maximum deceleration that the vehicle can brake with the motor M refers to the deceleration caused by the maximum possible regenerative braking torque that can be achieved by the motor, taking into account the state of charge (SOC) value of the battery, the motor temperature, the inverter temperature, etc. (see Figure 4 ), the maximum deceleration that the vehicle can achieve by braking with the motor M based on the current vehicle speed refers to the maximum deceleration that can be achieved by utilizing the regenerative braking of the motor M while taking into account the current vehicle speed and the friction characteristics of the road.

[0059] For reference, since the braking torque required to achieve the desired deceleration is the required braking torque, the desired deceleration and the required braking torque can be easily converted into each other.

[0060] In addition, Figure 5 In the figure, the ratio of the braking force to the total vehicle weight can be easily converted into a braking torque by the total vehicle weight and the dynamic load radius of the brake wheel.

[0061] In interval 1, the braking force distribution line is formed by a straight line DL1 connecting the control point B from the origin where all braking forces of the front and rear wheels are 0; in interval 1, when the deceleration required by the driver changes, the controller CLR controls the motor M to meet the required deceleration using only regenerative braking.

[0062] That is, if the required deceleration determined according to the driver's brake pedal stroke falls within interval 1, the present invention does not use the friction brake mechanism BK but controls only the motor M to generate a braking torque configured to meet the required deceleration through regenerative braking alone.

[0063] At this time, the braking torque according to the required deceleration is distributed to the front and rear wheels along the braking force distribution line of section 1, and the ratio of the front wheel braking torque to the rear wheel braking torque is generally determined by the gear ratio of the planetary gear set PG.

[0064] In interval 2, the braking force distribution line is formed by a straight line DL2 connecting control point B and control point C; in interval 2, when the deceleration required by the driver changes, the controller CLR controls the motor M so that the regenerative braking can maintain the level of control point B and only adds the friction braking of the friction braking mechanism BK thereto, thereby controlling the motor M to meet the required deceleration.

[0065] That is, if the deceleration required by the driver falls within interval 2, the controller CLR does not increase the regenerative braking torque of the motor M, and only increases the friction braking of the friction braking mechanism BK while maintaining the regenerative braking torque at the control point B (the control point B is the boundary between interval 1 and interval 2) as it is, thereby achieving the braking torque according to the required deceleration.

[0066] That is, even if the required deceleration falls into certain areas of interval 2 that are less than the maximum deceleration at which the vehicle can be braked by the motor M (the maximum deceleration can be achieved based on the characteristics of the motor M itself), only the braking torque of the friction brake is increased while keeping the regenerative braking torque as it is, because the required deceleration is a required deceleration that is greater than the maximum deceleration at which the vehicle can be braked by the motor M considering the current speed of the vehicle.

[0067] For reference, in this section 2 , the reason why the braking force distribution line DL2 is drawn in parallel with the same slope as that of the simple braking force distribution line P is because, as described above, only the friction braking torque is increased while the regenerative braking torque remains as it is.

[0068] In interval 3, the braking force distribution line is formed by a straight line DL3 connecting control point C and control point D; in interval 3, if the deceleration required by the driver increases, the controller CLR controls the friction mechanism BK to increase friction braking while gradually reducing the regenerative braking of the motor M, thereby meeting the required deceleration.

[0069] As the driver's desired deceleration increases throughout interval 3 , controller CLR linearly reduces the regenerative braking of motor M from the level at control point B to zero.

[0070] That is to say, if Figure 6 As shown, when the required deceleration increases linearly in this interval 3, as a result, the regenerative braking torque of the motor M decreases linearly to 0, and the friction braking torque of the friction braking mechanism BK increases linearly, thereby satisfying the required deceleration.

[0071] In this range, there is a disadvantage in that the regenerative braking force is reduced, but locking of the rear wheels can be prevented by setting the braking force distribution line in the direction of reducing the rear wheel braking force, thereby improving the braking stability of the vehicle.

[0072] In section 4, the braking force distribution line is formed by a straight line DL4 extending from the control point D along the simple braking force distribution line P; in section 4, when the driver's required deceleration increases, the controller CLR controls the friction braking force of the friction brake mechanism BK to increase linearly as a result.

[0073] That is, in such a high deceleration-required range, the controller CLR controls the friction brake mechanism BK along the simple braking force distribution line P of the friction brake mechanism BK to perform braking according to the braking force distribution between the front and rear wheels as in the conventional art.

[0074] For reference, in the aforementioned interval, it can be seen that the distribution of front wheel braking torque and rear wheel braking torque (step S20) and the distribution of regenerative braking torque and friction braking torque (step S30) are performed substantially synchronously according to the braking torque distribution map.

[0075] Meanwhile, in generating the braking torque distribution map (step S10 ), the controller CLR may determine the friction characteristics of the road using the degree of wheel slip.

[0076] That is, since the controller CLR may not be able to directly confirm the friction characteristics of the road, the friction characteristics of the corresponding road are estimated using the degree of wheel slip at that time.

[0077] Of course, in the event that the friction characteristics of the respective road are additionally received via a navigation system, vehicle to something (V2X) or the like, the controller CLR can also utilize this information.

[0078] In addition, the term "controller" or "control unit" refers to a hardware device including a memory and a processor, wherein the processor is configured to execute one or more steps interpreted as an algorithmic structure. The memory stores the algorithmic steps, and the processor executes the algorithmic steps to perform one or more processes of the method according to various exemplary embodiments of the present invention. The controller according to the exemplary embodiment of the present invention can be implemented by a non-volatile memory and a processor, wherein the non-volatile memory is configured to store algorithms for controlling the operation of various components of the vehicle or data about software commands for executing the algorithms, and the processor is configured to perform the above operations using data stored in the memory. The memory and the processor can be separate chips. Alternatively, the memory and the processor can be integrated into a single chip. The processor can be implemented as one or more processors.

[0079] The controller or control unit may be at least one microprocessor operated by a predetermined program that may include a series of commands for executing the methods according to various exemplary embodiments of the present invention.

[0080] The present invention described above can also be implemented as computer-readable code on a computer-readable recording medium. A computer-readable recording medium is any data storage device that can store data, which can then be read by a computer system. Examples of computer-readable recording media include hard disk drives (HDDs), solid-state disks (SSDs), silicon disk drives (SDDs), read-only memories (ROMs), random-access memories (RAMs), CD-ROMs, magnetic tapes, floppy disks, optical data storage devices, and the like, and can also be implemented as carrier waves (e.g., for transmission over the Internet).

[0081] For ease of explanation and precise definition in the appended claims, the terms "up," "down," "inside," "outside," "above," "below," "upward," "downward," "front," "back," "inside," "outside," "inwardly," "outwardly," "inner," "external," "inner," "external," "inner," "outwardly," "forward," and "rearwardly" are used to describe features of the exemplary embodiments with reference to the positions of such features as shown in the accompanying drawings. It will be further understood that the term "connect" or its derivatives refers to both direct and indirect connections.

[0082] Furthermore, the term “fixedly connected” means that the fixedly connected members always rotate at the same speed. Furthermore, the term “selectively connectable” means that “when the selectively connectable members are not engaged with each other, the selectively connectable members rotate individually, when the selectively connectable members are engaged with each other, the selectively connectable members rotate at the same speed, and when at least one of the selectively connectable members is a stationary member and the remaining selectively connectable members are engaged to the stationary member, the selectively connectable members are stationary.”

[0083] The foregoing descriptions of specific exemplary embodiments of the present invention are presented for purposes of illustration and description. These descriptions are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and it is apparent that many modifications and variations are possible in light of the foregoing teachings. The exemplary embodiments have been selected and described to illustrate the specific principles of the invention and its practical application, so as to enable others skilled in the art to make and utilize the various exemplary embodiments of the invention and various alternatives and modifications thereof. The scope of the invention is intended to be defined by the appended claims and their equivalents.

Claims

1. A powertrain device for a vehicle, the powertrain device comprising: Motor; a planetary gear set including a first rotating element, a second rotating element, and a third rotating element, wherein the first rotating element of the planetary gear set exchanges power with the motor; a front wheel drive shaft engaged with the planetary gear set to receive power from the second rotation element of the planetary gear set and transmit the rotational force to the front wheels coupled to the front wheel drive shaft; a rear wheel drive shaft engaged with the planetary gear set and installed to receive power from the third rotation element of the planetary gear set to transmit rotational force to the rear wheels coupled to the rear wheel drive shaft, wherein the rotating shaft of the motor is coupled to the first rotating element of the planetary gear set to exchange power therebetween; The rotating shaft of the motor is formed by a hollow shaft; One of the front wheel drive shaft and the rear wheel drive shaft is installed to pass through the interior of the rotating shaft of the motor; The first gear is fixedly connected to the rotating shaft of the motor; A second gear meshing with the first gear is fixedly connected to a first rotating element of the planetary gear set; A third gear is fixedly connected to the second rotation element of the planetary gear set; The fourth gear meshing with the third gear is fixedly connected to one of a front wheel drive shaft and a rear wheel drive shaft installed as a rotation shaft penetrating the motor.

2. The powertrain device for a vehicle according to claim 1, wherein The first rotating element is a planet carrier, the second rotating element is a ring gear, and the third rotating element is a sun gear.

3. The powertrain device for a vehicle according to claim 1, wherein a fifth gear fixedly connected to the third rotation element of the planetary gear set; The sixth gear meshing with the fifth gear is fixedly connected to the other of the front wheel drive shaft and the rear wheel drive shaft.

4. The powertrain device for a vehicle according to claim 1, wherein The planetary gear set is a double pinion planetary gear set; A rotation shaft of the motor is coupled to the second rotation element of the planetary gear set to exchange power therebetween.

5. The powertrain device for a vehicle according to claim 4, wherein The first rotating element is a planet carrier, the second rotating element is a ring gear, and the third rotating element is a sun gear.

6. The powertrain device for a vehicle according to claim 4, wherein The rotating shaft of the motor is formed by a hollow shaft; One of the front wheel drive shaft and the rear wheel drive shaft is installed to penetrate an interior of a rotation shaft of a motor.

7. The powertrain device for a vehicle according to claim 6, wherein: The first gear is fixedly connected to the rotating shaft of the motor; a second gear meshing with the first gear and fixedly connected to a second rotating element of the planetary gear set; A third gear is fixedly connected to the first rotation element of the planetary gear set; The fourth gear meshing with the third gear is fixedly connected to one of a front wheel drive shaft and a rear wheel drive shaft installed as a rotation shaft penetrating the motor.

8. The powertrain device for a vehicle according to claim 7, wherein: a fifth gear fixedly connected to the third rotation element of the planetary gear set; A sixth gear meshing with the fifth gear is provided on the other of the front wheel drive shaft and the rear wheel drive shaft.

9. A braking control method for a powertrain device according to claim 1, the braking control method comprising: Using the ideal braking force diagram, a controller generates a braking torque distribution map based on vehicle speed, road friction characteristics, and maximum possible regenerative braking torque. Distributing the braking torque between the front and rear wheels through a controller according to a braking torque distribution map and the required braking torque; distributing the distributed braking torque of the front wheels and the rear wheels into regenerative braking torque and friction braking torque by a controller; The controller controls the motor according to the regenerative braking torque, and performs friction braking using the friction braking mechanism according to the friction braking torque. The ideal braking force diagram includes control points A, B, C, and D. Control point A is the intersection of an ideal braking force distribution line for braking the vehicle by the motor and a maximum deceleration line for braking the vehicle by the motor. Control point B is the intersection of a straight line connecting control point A from an origin where the braking force of the front and rear wheels is 0 and a maximum deceleration line for braking the vehicle by the motor based on the current vehicle speed. Control point C is the intersection of a straight line extending from control point B with the same slope as a simple braking force distribution line of a braking device intersecting the ideal braking force distribution line, wherein the braking device has a constant front and rear wheel braking force distribution ratio. Control point D is the intersection of the simple braking force distribution line and the ideal braking force distribution line. The braking torque distribution map includes: a deceleration area at or below control point B and set as interval 1, a deceleration area exceeding control point B and at or below control point C and set as interval 2, a deceleration area exceeding control point C and at or below control point D and set as interval 3, and a deceleration area exceeding control point D and set as interval 4; For each of intervals 1, 2, 3, and 4, the braking force of the front wheels and the rear wheels is distributed according to different braking force distribution lines.

10. The method according to claim 9, wherein: In interval 1, the braking force distribution line includes a straight line connecting the control point B from the origin where the braking force of the front and rear wheels is 0; In interval 2, the braking force distribution line includes a straight line connecting control point B to control point C; In interval 3, the braking force distribution line includes a straight line connecting control point C to control point D; In section 4 , the braking force distribution line includes a straight line extending from control point D along the simple braking force distribution line.

11. The method according to claim 9, wherein In interval 1, the braking force distribution line includes a straight line connecting the control point B from the origin where the braking force of the front and rear wheels is 0; In interval 1, when the driver's desired deceleration changes, the controller is configured to utilize regenerative braking of the electric machine to meet the desired deceleration.

12. The method according to claim 11, wherein In interval 2, the braking force distribution line includes a straight line connecting control point B to control point C; In interval 2, when the deceleration required by the driver changes, the controller is configured to control the motor so that the regenerative braking can maintain the level of control point B and add friction braking of the friction braking mechanism thereto, thereby satisfying the required deceleration.

13. The method according to claim 12, wherein: In interval 3, the braking force distribution line includes a straight line connecting control point C to control point D; In interval 3 , when the deceleration required by the driver increases, the controller is configured to increase the friction braking of the friction braking mechanism while reducing the regenerative braking of the motor, thereby satisfying the required deceleration.

14. The method according to claim 13, wherein: As the driver's desired deceleration increases throughout interval 3, the controller is configured to linearly reduce the regenerative braking of the electric machine from the level of control point B to zero.

15. The method according to claim 13, wherein In interval 4, the braking force distribution line includes a straight line extending from control point D along the simple braking force distribution line; In interval 4 , when the deceleration required by the driver increases, the controller is configured to linearly increase the friction braking force of the friction brake mechanism.

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