Device and method for controlling a disconnect device of an electric vehicle

Abstract

The present invention relates to an apparatus and method for controlling a disconnecting device of an electric vehicle. The control apparatus of the disconnecting device includes a disconnecting device for switching a driving mode of a wheel and a processor for recognizing a driving state of the vehicle. The processor also acquires at least one factor related to an operation of the disconnecting device and operates the disconnecting device based on the acquired at least one factor.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2020-0075887, filed on June 22, 2020, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to an apparatus and method for controlling a disconnection device of an electric vehicle, and more specifically, to an apparatus and method for controlling the engagement and disengagement of the disconnection device based on factors affecting the vehicle's driving conditions and the operation of the disconnection device. Background Technology

[0004] Disconnect coupling systems have been applied to environmentally friendly vehicles such as electric and hybrid vehicles. A disconnect coupling system is a device that reduces drag by controlling the reverse driving force transmitted from the motor to the wheels. Four-wheel drive (4WD) electric vehicles are equipped with disconnect couplings on either the front or rear wheels to transmit or control the motor's driving force as needed. In other words, when the vehicle accelerates or decelerates via the motor on the drive shaft equipped with the disconnect coupling system, the disconnect coupling engages to transmit motor torque to the wheels; when the motor on the drive shaft equipped with the disconnect coupling system is not in use, the disconnect coupling disengages to reduce drag generated in the motor and reducer, such as motor back electromotive force and reducer resistance.

[0005] When a vehicle is driven with the disconnector disengaged, fuel efficiency is improved due to reduced drag. However, when the disconnector is engaged for emergency vehicle control, it takes time to switch the operating mode of the disconnector from the disengaged state to the engaged state, which degrades vehicle control performance. Summary of the Invention

[0006] The present invention provides an apparatus and method for controlling the disconnection device of an electric vehicle, which controls the engagement and disengagement of the disconnection device based on factors affecting the vehicle's driving conditions and the operation of the disconnection device.

[0007] The technical problems to be solved by the present invention are not limited to those described above. Through the following description, those skilled in the art will clearly understand any other technical problems not mentioned herein.

[0008] According to one aspect of the present invention, a control device for a disconnection device for an electric vehicle may include: a disconnection device for switching wheel drive modes; and a processor configured to detect the vehicle's driving conditions, acquire at least one factor related to the operation of the disconnection device, and operate the disconnection device based on the acquired at least one factor. The driving conditions may include one of downhill driving conditions, cornering driving conditions, and constant speed driving conditions.

[0009] The processor can be configured to: when the driving condition is downhill, acquire road surface slope, regenerative braking torque, and wheel speed difference between the front and rear wheels using at least one of a navigation device and a sensing device. The processor can be configured to: determine a fraction of each of the road surface slope, regenerative braking torque, and wheel speed difference between the front and rear wheels, calculate a first operational fraction, and engage the disconnection device in response to determining that the calculated first operational fraction is greater than or equal to a first reference fraction.

[0010] Additionally, the processor can be configured to: when the driving condition is a turning driving condition, acquire the vehicle's steering angle, steering angular velocity, and yaw rate error using at least one of the navigation device and the sensing device. The processor can be configured to: determine a fraction of each of the vehicle's steering angle, steering angular velocity, and yaw rate error, calculate a second operational fraction, and engage the disconnection device in response to determining that the calculated second operational fraction is greater than or equal to a second reference fraction. The processor can also be configured to: when the driving condition is a constant speed driving condition, determine whether the speed difference between the constant speed vehicle speed and a first reference vehicle speed, or the speed difference between the constant speed vehicle speed and a second reference vehicle speed, is within a critical vehicle speed range.

[0011] The processor can be configured to: when the speed difference between the constant-speed vehicle and the speed of the first reference vehicle is within a critical vehicle speed range, perform an adjustment to decrease the speed of the first reference vehicle based on the initial value of the first reference vehicle speed, the constant-speed holding time, and the constant-speed holding speed. The processor can also be configured to: when the speed difference between the constant-speed vehicle and the speed of the second reference vehicle is within a critical vehicle speed range, perform an adjustment to increase the speed of the second reference vehicle based on the initial value of the second reference vehicle speed, the constant-speed holding time, and the constant-speed holding speed.

[0012] Additionally, the processor can be configured to: in response to determining that the speed of the uniformly traveling vehicle exceeds a first reference vehicle speed and is less than or equal to a second reference vehicle speed, and that the difference between the uniformly traveling torque and the reference torque is within a critical torque range, acquire an initial value of the reference torque, the frequency of change of the required torque, and the holding time of the high required torque in the mid-speed range. The processor can also be configured to: perform an adjustment to reduce the reference torque based on the initial value of the reference torque, the frequency of change of the required torque, and the holding time of the high required torque in the mid-speed range.

[0013] According to another aspect of the present invention, a control method for a disconnection device for an electric vehicle may include: detecting the driving conditions of the vehicle; acquiring at least one factor related to the operation of the disconnection device under the driving conditions; determining an operating mode of the disconnection device based on the at least one factor; and operating the disconnection device according to the determination.

[0014] Detecting driving conditions may include: detecting at least one of downhill driving conditions, cornering driving conditions, and constant speed driving conditions as driving conditions. Obtaining at least one factor may include: in downhill driving conditions, using at least one of a navigation device and a sensing device to obtain the road surface slope, regenerative braking torque, and the wheel speed difference between the front and rear wheels.

[0015] Determining the operating mode of the disconnect device may include: determining a fraction of each of the road surface slope, regenerative braking torque, and the wheel speed difference between the front and rear wheels to calculate a first operating score; comparing the first operating score with a first reference score; and determining engagement of the disconnect device in response to determining that the calculated first operating score is greater than or equal to the first reference score. Acquiring at least one factor may include: in cornering conditions, using at least one of a navigation device and a sensing device to acquire the vehicle's steering angle, steering angular velocity, and yaw rate error. Determining the operating mode of the disconnect device may include: determining a fraction of each of the vehicle's steering angle, steering angular velocity, and yaw rate error to calculate a second operating score; comparing the second operating score with a second reference score; and determining engagement of the disconnect device when the calculated second operating score is greater than or equal to the second reference score.

[0016] Obtaining at least one factor may include: determining, under constant speed conditions, whether the speed difference between the constant speed vehicle speed and the speed of a first reference vehicle is within a critical vehicle speed range; determining whether the speed difference between the constant speed vehicle speed and the speed of a second reference vehicle is within a critical vehicle speed range; and, in response to determining that the speed difference between the constant speed vehicle speed and the speed of the first reference vehicle speed or the speed difference between the constant speed vehicle speed and the speed of the second reference vehicle speed is within a critical vehicle speed range, obtaining the initial value of the first reference vehicle speed or the second reference vehicle speed, the constant speed holding time, and the constant speed holding speed.

[0017] Determining the operating mode of the disconnection device may include: adjusting the speed of the first reference vehicle to decrease based on an initial value of the first reference vehicle speed, a constant speed holding time, and a constant speed holding speed; and determining the engagement or disengagement of the disconnection device based on the adjusted first reference vehicle speed. Determining the operating mode of the disconnection device may also include: adjusting the speed of the second reference vehicle to increase based on an initial value of the second reference vehicle speed, a constant speed holding time, and a constant speed holding speed; and determining the engagement or disengagement of the disconnection device based on the adjusted second reference vehicle speed.

[0018] Obtaining at least one factor may include: under constant speed driving conditions, in response to determining that the constant speed driving vehicle speed is greater than a first reference vehicle speed and less than or equal to a second reference vehicle speed, determining whether the difference between the constant speed driving torque and the reference torque is within a critical torque range; when the difference between the constant speed driving torque and the reference torque is within the critical torque range, obtaining the initial value of the reference torque, the frequency of change of the required torque, and the holding time of the high required torque in the mid-speed range. Determining the operating mode of the disconnection device may include: performing an adjustment to reduce the reference torque based on the initial value of the reference torque, the frequency of change of the required torque, and the holding time of the high required torque in the mid-speed range. Attached Figure Description

[0019] The above and other objects, features, and advantages of the invention will become more clearly understood from the detailed description presented thereafter in conjunction with the accompanying drawings:

[0020] Figure 1 A block diagram illustrating an electric vehicle according to the present invention;

[0021] Figure 2 This is a configuration block diagram of an electric vehicle according to an exemplary embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram illustrating a strategy for engaging and disengaging a connection device during constant-speed travel, according to an exemplary embodiment of the present invention.

[0023] Figures 4A to 4DA flowchart illustrating a method for controlling a disconnection device for an electric vehicle according to another exemplary embodiment of the present invention;

[0024] Figure 5 A flowchart illustrating a method for controlling a disconnection device for an electric vehicle according to another exemplary embodiment of the present invention;

[0025] Figure 6 A flowchart illustrating a method for controlling a disconnection device for an electric vehicle according to another exemplary embodiment of the present invention;

[0026] Figure 7 A flowchart illustrating a method for delaying the disconnection of a control device for an electric vehicle according to an exemplary embodiment of the present invention; and

[0027] Figure 8 This is a block diagram of a computing system for executing a method of controlling the disconnection device of an electric vehicle according to an exemplary embodiment of the present invention. Detailed Implementation

[0028] It should be understood that the term "vehicle" or "of a vehicle" or other similar terms as used herein generally includes motor vehicles, such as passenger cars including sport utility vehicles (SUVs), buses, trucks, and various commercial vehicles, boats including various vessels and ships, aircraft, etc., and includes hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles, and other alternative fuel vehicles (e.g., fuels derived from non-fossil energy sources). As mentioned herein, a hybrid vehicle is a vehicle with two or more power sources, such as both gasoline power and electric power.

[0029] Although the exemplary embodiments are described as utilizing multiple units to perform the exemplary process, it should be understood that the exemplary process may also be performed by one or more modules. Furthermore, it should be understood that the term controller / control unit refers to a hardware device that includes a memory and a processor and is specifically programmed to perform the processes described herein. The memory is configured to store modules, and the processor is specifically configured to run the modules to perform one or more processes further described below.

[0030] Furthermore, the control logic of the present invention can be implemented as a non-volatile computer-readable medium on a computer-readable medium, comprising executable program instructions that are executed by a processor, controller / control unit, etc. Examples of computer-readable media include, but are not limited to, ROM, RAM, optical disc (CD)-ROM, magnetic tape, floppy disk, flash drive, smart card, and optical data storage device. The computer-readable recording medium can also be distributed across a network-connected computer system, allowing the computer-readable medium to be stored and executed in a distributed manner, for example, via a telematics server or a controller area network (CAN).

[0031] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should be further understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of the stated features, values, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, values, steps, operations, elements, components, and / or groups thereof. As used herein, the term “and / or” includes any and all combinations of one or more of the related enumerations.

[0032] Unless otherwise stated or obvious from the context, the term “about” as used herein is understood to mean within the normal tolerance range in the field, such as within 2 standard deviations of the mean. “About” can be understood as within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the specified value. All numerical values ​​provided herein are modified by the term “approximately” unless clearly stated from the context.

[0033] Hereinafter, certain embodiments of the invention will be described in detail with reference to the exemplary accompanying drawings. When adding reference numerals to components in each drawing, it should be noted that the same reference numerals are used to denote components that are identical or equivalent even when shown in other drawings. Furthermore, in describing exemplary embodiments of the invention, detailed descriptions of well-known features or functions will be omitted to avoid unnecessarily obscuring the spirit of the invention.

[0034] In describing components according to exemplary embodiments of the present invention, terms such as first, second, "A", "B", (a), (b), etc., may be used. These terms are intended only to distinguish one component from another, and they do not limit the nature, order, or sequence of the constituent components. Unless otherwise defined, all terms used herein, including technical or scientific terms, shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Such terms, as defined in a general dictionary, shall be interpreted as having the same meaning as in the context of the relevant technical field and shall not be interpreted as having an ideal or overly formal meaning unless such meaning is expressly defined in this application.

[0035] Figure 1 A block diagram illustrating an electric vehicle according to the present invention. (Reference) Figure 1 The electric vehicle (hereinafter, the vehicle) 100 may include: a first motor 110, a second motor 120, a first reducer 130, a second reducer 140, a first differential gear 150, a second differential gear 160, a disconnection device 170, and a battery 180.

[0036] The first motor 110 and the second motor 120 can be drive devices that convert electrical energy into kinetic energy to generate the driving force required to drive wheels FW1, FW2, RW1, and RW2. The first motor 110 and the second motor 120 can adjust their output torque according to instructions from a motor control unit (MCU) by adjusting the direction of rotation, rotational speed (e.g., revolutions per minute, RPM), etc. The first motor 110 can be configured to supply driving force to the rear wheels RW1 and RW2, and the second motor 120 can be configured to supply driving force to the front wheels FW1 and FW2. The first motor 110 and the second motor 120 can function as generators that charge the battery 180 by generating back electromotive force when the state of charge (SOC) is insufficient or during regenerative braking.

[0037] The first reducer 130 and the second reducer 140 can be a transmission designed to efficiently transmit the driving force generated by the motors 110 and 120 to the wheels FW1, FW2, RW1, and RW2. The first reducer 130 can be configured to regulate the rotational speed (motor torque) of the first motor 110 and transmit the rotational speed to the rear wheels RW1 and RW2, and the second reducer 140 can be configured to regulate the rotational speed (motor torque) of the second motor 120 and transmit the rotational speed to the front wheels FW1 and FW2.

[0038] The first differential gear 150 and the second differential gear 160 can be connected to the output terminals of the first reducer 130 and the second reducer 140, respectively, and distribute and transmit the output torque of the first reducer 130 and the second reducer 140 to wheels FW1, FW2, RW1, and RW2. The first differential gear 150 can distribute and transmit the driving force generated by the first motor 110 to both rear wheels RW1 and RW2. Additionally, the second differential gear 160 can distribute and transmit the driving force generated by the second motor 120 to both front wheels FW1 and FW2.

[0039] The disconnector 170 can be mounted on an axle and can be positioned between the differential gear 150 or 160 and wheels FW1, FW2, RW1, or RW2. In this exemplary embodiment, for ease of understanding, the disconnector 170 is described as being positioned on the front axle drive shaft as an example, but it can also be positioned on the rear axle drive shaft. The disconnector 170 can be configured to transmit or disconnect driving forces from the second motor 120 and the second reducer 140 to the front wheels FW1 and FW2. The disconnector 170 can be engaged or disengaged according to instructions from the control device 240 of the disconnector 170, which will be described later. When the disconnector 170 is engaged, the vehicle 100 can operate in four-wheel drive (4WD) mode (i.e., all-wheel drive (AWD) mode). Additionally, when the disconnector 170 is disengaged, the vehicle 100 can operate in rear-wheel drive mode.

[0040] Battery 180 can be configured to provide the power required to drive the vehicle, and can be implemented using a high-voltage battery. Battery 180 can be configured to supply power to a first motor 110 and a second motor 120. Battery 180 can be charged using regenerative energy generated by motors 110 and 120. Although not shown in the figures, vehicle 100 may include a Battery Management System (BMS) configured to monitor the state of charge and discharge of battery 180, detect anomalies occurring in battery 180, and take appropriate measures. Additionally, a power converter can be further provided in vehicle 100, configured to convert the voltage output from battery 180 and supply drive voltage to the motors. The power converter may include an inverter and a low-voltage DC-DC converter (LDC), the inverter configured to convert the direct current (DC) power from battery 180 into alternating current (AC) power to regulate the speed of motors 110 and 120; the LDC configured to convert the high voltage output from battery 180 into a low voltage to supply a low voltage to the electrical system.

[0041] Figure 2 This is a configuration block diagram of an electric vehicle according to an exemplary embodiment of the present invention; Figure 3This is a schematic diagram illustrating a strategy for engaging and disengaging a connection device during constant-speed travel, according to an exemplary embodiment of the present invention. (Reference) Figure 2 The electric vehicle (hereinafter, the vehicle) 100 may include a navigation device 210, a sensing device 220, an output device 230, and a control device 240 for disconnection devices, which are connected via a bus 200. For example, the bus 200 may be implemented using a controller area network (CAN), a media-oriented system transport (MOST) network, a local interconnect network (LIN), Ethernet, and / or Flexray.

[0042] When a destination is set, navigation device 210 can be configured to search for and guide a route to that destination. While searching for a route, navigation device 210 can reflect real-time traffic information to search for the optimal route. Navigation device 210 can be configured to send road information (e.g., road gradient (inclination), road curvature (turning radius and / or turning angle) and / or blind spots) to control device 240 of the disconnected device. Navigation device 210 may include: a memory configured to store map data; a Global Positioning System (GPS) receiver configured to measure vehicle position; a communication module configured to receive traffic information from an external source; and a processor configured to search for a route and perform route guidance along that route, which are not shown in the figure.

[0043] The sensing device 220 can be configured to acquire driving information using at least one sensor mounted on the vehicle 100. The sensing device 220 can utilize at least one of the following sensors: a steering angle sensor, a wheel speed sensor, a vehicle speed sensor, a 3-axis accelerometer, an inertial measurement unit (IMU), an accelerator pedal position sensor, an image sensor, a rain sensor, a yaw rate sensor, and / or a temperature sensor. Driving information may include vehicle speed, wheel speed, motor rotation speed (revolutions per minute, RPM), road gradient (inclination), turning angle (road curvature), yaw rate, rainfall, and temperature, etc.

[0044] Output device 230 can be configured to output various types of information, such as disconnection status information (e.g., engaged or disengaged), motor RPM, vehicle speed, remaining fuel distance (DTE), and / or warnings. Output device 230 may include a display, a speaker, a tactile signal output device (e.g., a vibrator), etc. The display may include at least one of the following: liquid crystal display (LCD), thin-film transistor liquid crystal display (TFT-LCD), organic light-emitting diode (OLED) display, flexible display, 3D display, transparent display, head-up display (HUD), touchscreen, and instrument cluster.

[0045] The control device 240 for the disconnection device can be configured to detect the current driving condition of the vehicle 100 and acquire at least one factor regarding the operation of the disconnection device 170 under the corresponding driving condition. The control device 240 can switch wheel drive modes by engaging or disengaging the disconnection device 170 based on the acquired at least one factor. The control device 240 for the disconnection device may include a processor 241 and a memory 242. The processor 241 can be configured to perform the overall operation of the control device 240 for the disconnection device and is implemented using at least one of an application-specific integrated circuit (ASIC), a digital signal processor (DSP), a programmable logic device (PLD), a field-programmable gate array (FPGA), a central processing unit (CPU), a microcontroller, and a microprocessor. The memory 242 can be a non-volatile storage medium storing instructions to be executed by the processor 241.

[0046] Memory 242 can be configured to store input data and / or output data generated according to the operation of processor 241. Memory 242 can be configured to store various setting information. Memory 242 can be implemented using at least one of the following storage media: for example, flash memory, hard disk, SD card (Secure Digital Card), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), programmable read-only memory (PROM), electrically erasable programmable ROM (EEPROM), erasable programmable ROM (EPROM), registers, and cache memory.

[0047] Processor 241 can be configured to identify the driving conditions (driving status) of vehicle 100 via navigation device 210 and / or sensing device 220. Driving conditions can be situations requiring adjustment of the engagement and disengagement timing of disconnector 170, and can be specified as downhill driving (downhill road), turning driving, and constant speed driving. In other words, driving conditions can represent the likelihood that switching between engagement and disengagement of disconnector 170 occurs frequently. Processor 241 can be configured to identify factors (related factors) affecting the operation (engagement or disengagement) of disconnector 170 under detected driving conditions, and determine a disconnector control strategy based on the identification results. Processor 241 can be configured to operate disconnector 170 according to the determined disconnector control strategy.

[0048] The following section will describe in detail the method for determining the disconnection device control strategy for each driving condition.

[0049] #Downhill driving conditions

[0050] like Figure 1 As shown, when a vehicle 100 equipped with a disconnect coupling device 170 on its front wheels FW1 and FW2 is traveling downhill with the disconnect coupling device 170 disengaged, the vehicle 100's center of gravity can shift to the front wheels FW1 and FW2. Therefore, the traction of the rear wheels RW1 and RW2 may decrease, making them prone to slippage. Thus, it is necessary to engage the disconnect coupling device 170 early to distribute regenerative braking between the front and rear wheels.

[0051] Therefore, processor 241 can be configured to acquire road gradient, regenerative braking torque, and / or the wheel speed difference between the front and rear wheels as relevant factors (first relevant factor) when vehicle 100 needs to perform downhill driving. Processor 241 can be configured to receive road gradient from navigation device 210 or to measure road gradient using sensing device 220. Additionally, processor 241 can be configured to estimate regenerative braking torque based on road gradient (surface slope) and vehicle speed. The wheel speed difference between the front wheels FW1 and FW2 and the rear wheels RW1 and RW2 can be calculated using wheel speed sensors located on the front wheels FW1 and FW2 and the rear wheels RW1 and RW2.

[0052] Processor 241 can be configured to score the acquired factors individually. Specifically, processor 241 can be configured to determine the score for each factor by referring to a score calculation reference table (as shown in [Table 1]) pre-stored in memory 242. Processor 241 can be configured to calculate (operate) a first operation score by summing the scores of predetermined factors. Then, processor 241 can be configured to determine early engagement of disconnect device 170 in response to determining that the calculated first operation score is greater than or equal to the first reference score, and to determine disengagement of disconnect device 170 in response to determining that the calculated first operation score is less than the first reference score.

[0053] For example, when the road gradient is -10%, the regenerative braking torque is 100 Nm, and the wheel speed difference between the front and rear wheels is 2.5 kph, the processor 241 can be configured to determine 5, 0, and 5 points for each factor, and calculate the sum of the determined scores (i.e., 10 points). Since the calculated sum of scores, 10 points, is greater than or equal to 10 points (which is a reference score), the processor 241 can be configured to determine the engagement of the disconnecting connection device.

[0054] Table 1

[0055]

[0056]

[0057] #Turning driving conditions

[0058] In rear-wheel drive vehicles, there is a tendency for oversteer when cornering, while in front-wheel drive vehicles, there is a tendency for understeer. However, in four-wheel drive vehicles, neutral steering can be achieved by distributing drive force to both the front and rear wheels during cornering. Therefore, when the disconnector 170 of vehicle 100 is disengaged—that is, when driving the vehicle in two-wheel drive mode—the delayed engagement of the disconnector during an emergency turn makes it difficult to achieve neutral steering, thus deteriorating cornering performance. Therefore, it may be necessary to engage the disconnector 170 earlier when cornering.

[0059] Therefore, when vehicle 100 needs to turn, processor 241 can be configured to acquire the steering angle, steering angular velocity, and / or yaw rate error of vehicle 100 as relevant factors (second relevant factors). Processor 241 can be configured to estimate the steering angle and steering angular velocity of the turn based on road curvature (turning radius). Specifically, road curvature can be provided from navigation device 210 or can be measured using sensing device 220. In addition, processor 241 can be configured to identify the yaw rate error of vehicle 100 using steering angle sensor, yaw rate sensor, etc.

[0060] Processor 241 can be configured to score the acquired factors individually. Specifically, processor 241 can be configured to determine the score for each factor by referring to a score calculation reference table (as shown in [Table 2]) pre-stored in memory 242. Processor 241 can be configured to calculate (operate on) a second operation score by summing the scores of predetermined factors. Processor 241 can be configured to: determine early engagement of disconnect device 170 in response to determining that the calculated second operation score is greater than or equal to a second reference score (e.g., 10 points), and determine disengagement of disconnect device 170 in response to determining that the calculated second operation score is less than the second reference score.

[0061] For example, when the steering angle is 30 degrees, the steering angular velocity is 60 degrees / second, and the yaw rate error is 2.5 degrees / second, the processor 241 can be configured to determine scores of 0, 5, and 10 as factors, respectively, and calculate the sum of the determined scores (i.e., 15 points). Because the sum of the calculated scores is greater than or equal to 10 points (which is a reference score), the processor 241 can be configured to determine the engagement of the disconnecting connection device.

[0062] Table 2

[0063]

[0064] #Constant speed driving condition - low speed or high speed

[0065] In the case of a dual-motor electric vehicle 100 equipped with a disconnector 170, when the disconnector 170 is not engaged, the second motor 120 connected to the disconnector 170 cannot be utilized, thus preventing high output. Therefore, it may be necessary to determine the engagement and disengagement timing of the disconnector 170 based on the driver's desired torque (i.e., the amount of pressure applied to the accelerator pedal) and the vehicle speed. In other words, the disconnector 170 can engage when the driver depresses the accelerator pedal significantly to achieve high output, and disengage when the driver depresses the accelerator pedal only slightly to reduce drag and improve fuel efficiency. However, when the engagement and disengagement timing of the disconnector 170 is fixed based on the driver's desired torque and vehicle speed, frequent engagement and disengagement of the disconnector 170 may occur during constant-speed driving at these engagement and disengagement times.

[0066] As described above, when the engagement and disengagement of the disconnector 170 occur frequently, the energy consumption for switching between engagement and disengagement of the disconnector 170 may increase, reducing fuel efficiency, and the maximum output of the motor may fluctuate frequently, causing driver discomfort. To avoid the above situations, it may be necessary to change the timing of engagement and disengagement of the disconnector 170 according to the driver's preferences.

[0067] Therefore, processor 241 can be configured to identify the constant speed of vehicle 100 during constant speed travel. Processor 241 can be configured to compare the constant speed with a first reference vehicle speed and a second reference vehicle speed. Specifically, the first reference vehicle speed and the second reference vehicle speed can be vehicle speeds used as references for determining the engagement and disengagement of disconnection device 170, and correspond to the time points of engagement and disengagement of disconnection device 170.

[0068] The speed of the first reference vehicle can be less than the speed of the second reference vehicle. As a result of the comparison, the processor 241 can be configured to determine whether the difference between the constant-speed travel speed and the speed of the first reference vehicle is within a critical range (e.g., approximately -10 kph or more and 10 kph or less). Furthermore, as a result of the comparison, the processor 241 can be configured to determine whether the difference between the constant-speed travel speed and the speed of the second reference vehicle is within a critical range. The critical range can be preset by the system user along with the speeds of the first and second reference vehicles.

[0069] In response to determining that the difference between the constant speed and the first reference vehicle speed, or the difference between the constant speed and the second reference vehicle speed, is within a critical range (critical vehicle speed range), processor 241 may be configured to acquire initial values ​​(i.e., current settings) of the first reference vehicle speed and / or the second reference vehicle speed, constant speed holding time, and constant speed holding speed as relevant factors (third relevant factors). Processor 241 may be configured to identify the driver's tendencies and adjust the engagement and disengagement timing of disconnection device 170 by utilizing the acquired relevant factors. In other words, processor 241 may be configured to adjust the first reference vehicle speed and / or the second reference vehicle speed based on the acquired relevant factors.

[0070] More specifically, see reference Figure 3When the constant speed of vehicle 100 (constant speed vehicle speed) is approximately the initial value "a" of the first reference vehicle speed, the switching between engagement and disengagement of the disconnection device 170 may occur frequently, thereby degrading fuel efficiency. Therefore, processor 241 can be configured to change the first reference vehicle speed from "a" to "b" using the following equation 1, so that vehicle 100 travels in a two-wheel drive mode, thereby improving fuel efficiency. The first reference vehicle speed is the upper limit of the vehicle speed in the low-speed range.

[0071] Equation 1

[0072] b=a-(a'-a)·α·t1

[0073] Wherein, "b" is the first reference vehicle speed that varies in the low-speed range, "a" is the initial first reference vehicle speed in the low-speed range, "a'" is the constant speed maintained in the low-speed range, "α" is the engagement weight of the disconnecting connection device in the low-speed range, and "t1" is the constant speed maintained time in the low-speed range.

[0074] When the vehicle's constant speed is approximately equal to the initial value "c" of the second reference vehicle speed, the switching between engagement and disengagement of the disconnector 170 may occur frequently, thus degrading fuel efficiency. Therefore, the processor 241 can be configured to change the second reference vehicle speed from "c" to "d" using the following equation 2, so that the vehicle 100 travels in a two-wheel drive mode, thereby improving fuel efficiency. The second reference vehicle speed is the lower limit of the vehicle speed in the high-speed range.

[0075] Equation 2

[0076] d = c - (c' - c)·β·t²

[0077] Wherein, "d" is the second reference vehicle speed that varies in the high-speed range, "c" is the initial second reference vehicle speed in the high-speed range, "c'" is the constant speed maintained in the high-speed range, "β" is the engagement weight of the disconnecting connection device in the high-speed range, and "t2" is the constant speed maintained time in the high-speed range.

[0078] Subsequently, the processor can be configured to engage or disengage the disconnect device 170 based on the altered first or second reference vehicle speed, according to the constant speed of travel.

[0079] #Constant Speed ​​Driving Condition - Medium Speed

[0080] When the vehicle is traveling at a constant speed in the mid-speed range (i.e., greater than the first reference vehicle speed and less than or equal to the second reference vehicle speed), the processor 241 can be configured to identify the driver's desired torque. When high required torque for acceleration or overtaking is generated in the mid-speed range, 4WD drive may be essential for high output, thus requiring engagement of the disconnect device 170 to enable 4WD drive. On the other hand, when low required torque is generated in the mid-speed range, it may be necessary to disengage the disconnect device 170 to allow 2WD drive to improve fuel efficiency by reducing drag. Specifically, when the engagement and disengagement timing of the disconnect device 170 is fixed, the energy consumption for switching the engagement and disengagement of the disconnect device 170 may increase, reducing fuel efficiency, and the maximum output of the motor may change frequently, causing driver discomfort. To avoid the above situations, it may be necessary to change the engagement and disengagement timing of the disconnect device 170 according to the driver's preferences.

[0081] Processor 241 can be configured to compare the constant-speed driving torque with a preset reference torque. When the difference between the constant-speed driving torque and the reference torque is within a critical range, processor 241 can be configured to acquire the initial value of the reference torque, the frequency of change of the required torque, and the high required torque holding time in the medium-speed range as relevant factors (fourth relevant factor).

[0082] refer to Figure 3 When the torque at a constant speed is approximately equal to the initial value “e” of the reference torque, the processor 241 can use Equation 3 to change the reference torque from “e” to “f”.

[0083] Equation 3

[0084] f = e - (e' - e)·γ·t3

[0085] Wherein, "f" is the modified reference torque, "e" is the initial reference torque, "e'" is the medium-speed holding torque, γ is the engagement frequency (the frequency of change of the required torque), and "t3" is the holding time of the high required torque in the medium-speed range. Subsequently, the processor can engage or disengage the disconnect device 170 based on the modified reference torque and the constant-speed driving torque.

[0086] #Control the engagement and disengagement of the disconnection device based on external factors.

[0087] When vehicle 100 is traveling with disconnector 170 disengaged, engagement of the disconnector may be time-consuming if external factors change suddenly (e.g., sudden weather changes, road conditions changes, or blind spots), compromising safety during engagement. Therefore, a control strategy may be needed to proactively identify external factors and engage the disconnector. Thus, processor 241 can be configured to identify road information (e.g., curves, uphill and / or downhill slopes), information about blind spots, etc. Processor 241 can be configured to engage disconnector 170 when the road incline is greater than a reference incline, and to maintain disconnector 170 disengagement when the road incline is less than or equal to the reference incline.

[0088] Furthermore, the processor 241 can be configured to: maintain the disconnection of the disconnection device 170 when the turning radius of the road is greater than the reference radius, and engage the disconnection device 170 when the turning radius of the road is less than or equal to the reference radius. The processor 241 can also be configured to: engage the disconnection device 170 when the vehicle 100 is about to enter an accident blind spot, and maintain the disconnection of the disconnection device 170 when the vehicle 100 is about to enter a non-accident blind spot.

[0089] Additionally, the processor 241 can be configured to control the engagement and disengagement of the disconnection device 170 using a rain sensor, an external temperature sensor, or the like. The processor 241 can be configured to engage the disconnection device 170 when the rain sensor detects rainfall, and to keep the disconnection device 170 disengaged when no rainfall is detected. Furthermore, the processor 241 can be configured to engage the disconnection device 170 when the external temperature measured by the external temperature sensor is less than or equal to a reference temperature (e.g., 0°C), and to keep the disconnection device 170 disengaged when the external temperature is greater than the reference temperature.

[0090] #Disconnection delay control

[0091] When the disconnector 170 is engaged, high output and driving stability can be achieved through 4WD driving. However, during the engagement of the disconnector 170, fuel efficiency may deteriorate due to frequent engagement and disengagement, especially when the disconnector 170 disengages immediately at the disengagement point. Additionally, at the moment the disconnector 170 disengages, it may be difficult to respond quickly to various external factors, such as changes in road conditions, rapid cornering, and / or downhill or uphill driving. Therefore, when the disconnector 170 disengages, control measures may be necessary to delay its disengagement.

[0092] Therefore, when the disconnector 170 is engaged, when a signal indicating the disconnector 170 is generated (a disconnection signal), the processor 241 can postpone the disconnection of the disconnector until a predetermined time has elapsed or the vehicle has moved a predetermined distance. When the vehicle is traveling on an uphill, downhill, curved road, and / or low-friction road with the disconnector 170 in a delayed state of disengagement, if a signal indicating the disconnector 170 is engaged (an engagement signal) is generated, the processor 241 can maintain the engagement of the disconnector 170 until the next disconnection signal is generated.

[0093] Figures 4A to 4D A flowchart illustrating a method for controlling a disconnection device for an electric vehicle according to another exemplary embodiment of the present invention is provided; the processor 241 of the control device 240 for the disconnection device may be configured to identify the driving condition of the vehicle 100 (S110). The processor 241 may be configured to detect the driving condition via a navigation device 210 and / or a sensing device 220. The driving condition may be a situation requiring adjustment of the engagement and disengagement timing of the disconnection device 170, and may be specified as downhill driving, cornering, and constant speed driving.

[0094] Processor 241 can be configured to determine whether the driving condition of vehicle 100 is downhill driving (S120). In other words, processor 241 can be configured to determine whether vehicle 100 meets the downhill driving condition. Processor 241 can be configured to acquire a first relevant factor when vehicle 100 meets the downhill driving condition (S130). The first relevant factor may include road gradient, regenerative braking torque and / or the wheel speed difference between the front and rear wheels. Processor 241 can be configured to acquire the first relevant factor using navigation device 210 and / or sensing device 220.

[0095] Processor 241 can be configured to calculate an operation score based on a first relevant factor (S140). Processor 241 can be configured to determine the score for each factor by referring to a score calculation table stored in memory 242. Additionally, processor 241 can be configured to calculate the first operation score by summing the scores of the determined factors. Processor 241 can be configured to determine whether the calculated operation score is greater than or equal to a first reference score (S150). In this document, the first reference score can be a value preset by the system designer.

[0096] In response to determining that the calculated first operation score is greater than or equal to the first reference score, the processor 241 may be configured to determine the engagement of the disconnecting device (S160). For example, when the reference score is 10, the processor 241 may be configured to determine to engage the disconnecting device when the calculated first operation score is 15. On the other hand, in response to determining that the calculated first operation score is less than the first reference score, the processor 241 may be configured to determine to disengage the disconnecting device (disengagement of the disconnecting device) (S170). For example, the processor 241 may be configured to determine to disengage the disconnecting device when the calculated first operation score is 5 and less than the first reference score of 10.

[0097] Processor 241 can be configured to operate disconnector 170 based on the determination of engagement and disengagement of disconnector 170 (S180). Processor 241 can be configured to engage or disengage disconnector 170 based on the determination in S160 or S170. When the driving condition in S120 does not correspond to downhill driving, processor 241 can be configured to determine whether the driving condition is turning (S210). When the driving condition corresponds to turning, processor 241 can be configured to acquire a second relevant factor (S220). The second relevant factor may include the steering angle, steering angular velocity, and yaw rate error of vehicle 100. Processor 241 can be configured to estimate the steering angle and steering angular velocity for turning based on the road curvature (turning radius) acquired using navigation device 210 and / or sensing device 220. In addition, processor 241 can be configured to determine the yaw rate error of vehicle 100 using steering angle sensor, yaw rate sensor, etc.

[0098] Processor 241 can be configured to calculate a second operation score based on a second relevant factor (S230). Processor 241 can be configured to determine the score of each factor by referring to a score calculation reference table pre-stored in memory 242, and to calculate (operate on) the second operation score by summing the scores of the determined factors. Processor 241 can be configured to determine whether the calculated operation score is greater than or equal to the second reference score (S240). The second reference score may be equal to or different from the first reference score.

[0099] In response to determining that the calculated second operation score is greater than or equal to the second reference score, processor 241 may be configured to determine engagement of the disconnection device (S250). In response to determining that the calculated second operation score is less than the second reference score, processor 241 may be configured to determine disengagement of the disconnection device (S260). Processor 241 may be configured to operate disconnection device 170 based on the determination of engagement and disengagement of the disconnection device (S270). When engagement of the disconnection device is determined, processor 241 may engage the disconnection device 170 to enable the vehicle to travel in a four-wheel drive mode; when disengagement of the disconnection device is determined, processor 241 may disengage the disconnection device 170 to enable the vehicle to travel in a two-wheel drive mode.

[0100] When the driving condition in S210 does not correspond to turning, the processor 241 can be configured to determine whether the driving condition corresponds to constant speed driving (S310). Specifically, the processor 241 can be configured to determine whether constant speed driving is low-speed constant speed driving, medium-speed constant speed driving, or high-speed constant speed driving. The processor 241 can be configured to determine which of the low-speed, medium-speed, and high-speed ranges the constant speed driving speed of the vehicle 100 (i.e., the constant speed vehicle speed) belongs to, and accordingly determine whether it is low-speed constant speed driving, medium-speed constant speed driving, or high-speed constant speed driving. Specifically, the low-speed range can be a vehicle speed range that is less than the speed of the first reference vehicle, the high-speed range can be a vehicle speed range that is greater than the speed of the second reference vehicle, and the medium-speed range can be a vehicle speed range that is greater than the speed of the first reference vehicle but less than the speed of the second reference vehicle.

[0101] When the driving condition corresponds to constant speed driving, the processor 241 can be configured to determine whether the constant speed driving speed of the vehicle 100 (i.e., the constant speed driving vehicle speed) is approximately equal to the first reference vehicle speed (S320). The processor 241 can be configured to determine whether the difference between the constant speed driving vehicle speed and the first reference vehicle speed is within a critical range.

[0102] When the speed of the vehicle traveling at a constant speed is not approximately equal to the speed of the first reference vehicle, the processor 241 can be configured to determine whether the speed of the vehicle traveling at a constant speed is approximately equal to the speed of the second reference vehicle (S330). The processor 241 can be configured to determine whether the difference between the speed of the vehicle traveling at a constant speed and the speed of the second reference vehicle is within a critical range. The processor 241 can be configured to acquire a third relevant factor (S340) when the speed of the vehicle traveling at a constant speed is approximately equal to the speed of the first reference vehicle in S320, or when the speed of the vehicle traveling at a constant speed is approximately equal to the speed of the second reference vehicle in S330. For the third relevant factor, the initial value (or current set value) of the speed of the first reference vehicle and / or the speed of the second reference vehicle, the constant speed holding time, and the constant speed holding speed can be acquired as relevant factors.

[0103] Processor 241 can be configured to adjust the engagement and disengagement timing of the disconnection device using a third relevant factor (S350). Processor 241 can be configured to change the speed of a first reference vehicle or a second reference vehicle using the third relevant factor. When the constant-speed vehicle speed is approximately equal to the first reference vehicle speed, processor 241 can be configured to decrease the speed of the first reference vehicle based on the third relevant factor. When the constant-speed vehicle speed is approximately equal to the second reference vehicle speed, processor 241 can be configured to increase the speed of the second reference vehicle based on the third relevant factor.

[0104] Processor 241 can be configured to operate disconnector 170 based on the engagement and disengagement timing of the adjusted disconnector device (S360). Processor 241 can engage or disengage disconnector 170 based on the changed first reference vehicle speed and second reference vehicle speed. When the constant-speed vehicle speed is less than or equal to the changed first reference vehicle speed or greater than the changed second reference vehicle speed, processor 241 can engage disconnector 170. When the constant-speed vehicle speed is greater than the changed first reference vehicle speed or less than or equal to the changed second reference vehicle speed, processor 241 can disengage disconnector 170.

[0105] As described above, when the vehicle speed is approximately the first reference vehicle speed or the second reference vehicle speed under low-speed constant-speed driving conditions, it is possible to adjust the speed by decreasing the first reference vehicle speed or increasing the second reference vehicle speed, thereby enabling the vehicle to drive in two-wheel drive mode without switching between engaging and disengaging the disconnection device 170, thereby improving fuel efficiency.

[0106] Processor 241 can be configured to: determine whether the vehicle speed traveling at a constant speed is greater than the first reference vehicle speed and less than or equal to the second reference vehicle speed (S410) when the vehicle speed traveling at a constant speed in S330 is not approximately the second reference vehicle speed. Processor 241 can also be configured to: determine whether the vehicle speed traveling at a constant speed belongs to the medium speed range when the vehicle speed traveling at a constant speed is not approximately the first reference vehicle speed and the second reference vehicle speed. In other words, processor 241 can be configured to determine whether the driving condition of vehicle 100 corresponds to medium-speed constant speed driving.

[0107] Additionally, processor 241 can be configured to: determine whether the constant-speed driving torque is approximately the reference torque when the speed of the vehicle traveling at a constant speed is greater than the speed of the first reference vehicle and less than or equal to the speed of the second reference vehicle (S420). Processor 241 can also be configured to: determine whether the difference between the constant-speed driving torque and the reference torque is within a critical range (critical torque range) when the vehicle 100 is traveling at a medium speed at a constant speed.

[0108] When the constant-speed driving torque is approximately equal to the reference torque, processor 241 can be configured to acquire a fourth relevant factor (S430). When the difference between the constant-speed driving torque and the reference torque is within a critical range, processor 241 can be configured to acquire the initial value of the reference torque, the frequency of change of the required torque, and the holding time of the high required torque in the medium-speed range as relevant factors. Then, processor 241 can be configured to use the fourth relevant factor to adjust the engagement and disengagement timing of the disconnecting device (S440). Processor 241 can be configured to use the fourth relevant factor to perform an adjustment to reduce the reference torque.

[0109] Processor 241 can be configured to operate disconnector 170 based on the adjusted engagement and disengagement timings of the disconnector (S450). Processor 241 can then be configured to compare the constant-speed driving torque with a modified reference torque and engage or disengage disconnector 170 based on the comparison result. Disconnector 170 can operate based on a reduced reference torque, allowing the vehicle to travel in two-wheel drive without switching between engagement and disengagement of disconnector 170, thereby improving fuel efficiency.

[0110] Processor 241 can be configured to operate disconnect device 170 (S460) based on the engagement and disengagement timings of existing disconnect devices when the vehicle speed during constant-speed travel in S410 is less than or equal to a first reference speed or greater than a second reference speed, or when the torque during constant-speed travel in S420 is not approximately equal to a reference torque. Processor 241 can also be configured to control the engagement and disengagement of disconnect device 170 based on a preset first reference vehicle speed, second reference vehicle speed, and reference torque.

[0111] Figure 5 A flowchart illustrating a method for controlling a disconnection device for an electric vehicle according to another exemplary embodiment of the present invention is provided. This exemplary embodiment describes a method for operating the disconnection device 170 using navigation information. (Reference) Figure 5 The processor 241 can be configured to collect navigation information from the navigation device 210 when the disconnection device 170 is disconnected (S510). Specifically, the processor 241 can be configured to receive information about the road ahead of the vehicle 100 from the navigation device 210. The road ahead information may include the turning angle of the road ahead, the inclination of the road ahead, and whether there are blind spots.

[0112] Processor 241 can be configured to determine whether the forward turning angle in the navigation information is greater than a reference turning angle (S520). Additionally, processor 241 can be configured to determine whether the forward tilt angle in the navigation information is greater than a reference tilt angle (S530). Furthermore, processor 241 can be configured to determine, based on the navigation information, whether vehicle 100 has entered a blind spot (S540).

[0113] When the forward turning angle is greater than the reference turning angle, when the forward tilt is equal to or less than the reference tilt, and / or when the vehicle is not in the blind spot, the processor 241 can maintain the disconnected connection device 170 in the disengaged state (S550). On the other hand, when the forward turning angle is less than or equal to the reference turning angle, when the forward tilt is greater than the reference tilt, and / or when the vehicle enters the blind spot, the processor 241 can engage the disconnected connection device 170 (S560).

[0114] Figure 6 A flowchart illustrating a method for operating a disconnection device for an electric vehicle according to another exemplary embodiment of the present invention is provided. This exemplary embodiment describes a method for operating a disconnection device 170 using sensors mounted on a vehicle 100. Processor 241 may be configured to: acquire sensor information using sensors mounted on the vehicle 100 when the disconnection device 170 is disconnected (S610). Processor 241 may be configured to: acquire rainfall and external temperature (outside vehicle temperature) using a rain sensor and / or a temperature sensor.

[0115] Processor 241 can be configured to determine whether rainfall has been detected using a rain sensor (S620). Furthermore, processor 241 can be configured to determine whether the external temperature measured by a temperature sensor is less than or equal to a reference temperature (e.g., approximately 0°C) (S630). When rainfall is detected using the rain sensor and / or when the external temperature is less than or equal to the reference temperature, processor 241 can engage disconnect device 170 (S640). On the other hand, when no rainfall is detected and / or when the external temperature is greater than the reference temperature, processor 241 can maintain the disconnect device 170 in a disconnected state (S650).

[0116] In this exemplary embodiment, as an example, the engagement and disengagement of the disconnection device 170 are described based on whether a rain sensor detects rainfall. However, the invention is not limited thereto, and the engagement and disengagement of the disconnection device 170 can be determined based on the amount of rainfall detected by the rain sensor. For example, the processor 241 can be configured to: determine engagement of the disconnection device 170 when the amount of rainfall measured by the rain sensor is greater than a reference amount of rainfall, and determine disengagement of the disconnection device 170 when the measured amount of rainfall is less than or equal to the reference amount of rainfall.

[0117] Figure 7 A flowchart illustrating a method for delaying the separation of a disconnection device of an electric vehicle according to an exemplary embodiment of the present invention is provided. Processor 241 may be configured to detect the generation of a disconnection device separation signal (S710) when the vehicle 100 is traveling in a state where the disconnection device 170 is engaged. Processor 241 may also be configured to detect the disconnection device separation signal when a disconnection device separation signal is output from an algorithm (program) that determines the engagement or disengagement of the disconnection device according to the control method described above.

[0118] Processor 241 can be configured to: determine whether a disconnection device engagement signal is generated when a disconnection device separation signal is generated (S720). Processor 241 can be configured to: determine whether a disconnection device engagement signal is output from the algorithm for determining the engagement or separation of the disconnection device. Processor 241 can be configured to: determine whether a disconnection device separation delay condition is met when no disconnection device engagement signal is generated (S730). Processor 241 can be configured to: determine whether a predetermined time has elapsed after the generation of the disconnection device separation signal or whether the vehicle 100 has moved more than a predetermined distance.

[0119] In response to determining that vehicle 100 meets the disconnection delay condition, processor 241 may return to S720 to re-determine whether a disconnection engagement signal has been generated. Processor 241 may be configured to perform subsequent processing based on the result of the re-determination. In other words, after a disconnection engagement signal has been generated, processor 241 may delay the disconnection of disconnection device 170 until a predetermined time has elapsed and / or the vehicle has moved more than a predetermined distance.

[0120] When the disconnection delay condition of the disconnection device is not met, the processor 241 can disconnect the disconnection device 170 (S740). The processor 241 can be configured to switch the operating mode of the disconnection device 170 from the engaged state to the disengaged state after a predetermined time has elapsed and / or when the vehicle has moved more than a predetermined distance after the disconnection device disengagement signal is generated. When the disconnection device engagement signal is generated in S720, the processor 241 can maintain the engaged state of the disconnection device 170 (S750). When a signal indicating engagement of the disconnection device 170 (engagement signal) is generated, the processor 241 can maintain the engagement of the disconnection device 170 until the next disengagement signal is generated.

[0121] Figure 8 This is a block diagram of a computational system for executing a method of controlling a disconnection device for an electric vehicle according to an exemplary embodiment of the present invention. (Refer to...) Figure 8 The computing system 1000 may include at least one processor 1100, a memory 1300, a user interface input device 1400, a user interface output device 1500, a storage device 1600, and a network interface 1700, which are interconnected via a bus 1200. The processor 1100 may be a central processing unit (CPU) or a semiconductor device that processes instructions stored in the memory 1300 and / or the storage device 1600. The memory 1300 and the storage device 1600 may include various types of volatile or non-volatile storage media. For example, the memory 1300 may include a read-only memory (ROM) 1310 and a random access memory (RAM) 1320.

[0122] Therefore, the operation of the methods or algorithms described in conjunction with the embodiments disclosed herein can be directly implemented as hardware or software modules executed by processor 1100, or as a combination thereof. The software modules may reside in a storage medium (i.e., memory 1300 and / or storage device 1600), such as RAM, flash memory, ROM, EPROM, EEPROM, registers, hard disk, removable disk, and CD-ROM. This exemplary storage medium may be coupled to processor 1100, and processor 1100 may read information from and record information in the storage medium. Alternatively, the storage medium may be integrated with processor 1100. Processor 1100 and storage medium may reside within an application-specific integrated circuit (ASIC). The ASIC may reside within a user terminal. In another case, processor 1100 and storage medium may reside as separate components in the user terminal.

[0123] The above description merely illustrates the technical concept of the present invention. Those skilled in the art can make various modifications and variations without departing from the essential characteristics of the invention. Therefore, the embodiments disclosed in this invention are not intended to limit the technical concept of the invention, but rather to describe the invention, and the scope of the technical concept of the invention is not limited to the exemplary embodiments. The scope of protection of this invention should be interpreted by the appended claims, and all technical concepts within the scope of their equivalents should be interpreted as being included within the scope of this invention.

[0124] According to the present invention, the engagement and disengagement of the disconnection device can be controlled based on the vehicle's driving conditions and factors affecting the operation of the disconnection device, thereby improving fuel efficiency and operability (vehicle safety) in actual road conditions.

[0125] Although the invention has been described above with reference to exemplary embodiments and accompanying drawings, it is not limited thereto, and various changes and modifications will be apparent to those skilled in the art without departing from the spirit and scope of the invention as set forth by the appended claims.

Claims

1. A control device of a disconnect device for an electric vehicle, comprising: a disconnect device configured to switch a drive mode of a wheel; and a processor configured to detect a driving condition of the vehicle, acquire at least one factor related to an operation of the disconnect device, and operate the disconnect device based on the acquired at least one factor, wherein the driving condition includes a downhill driving condition, the processor is configured to: when the driving condition is the downhill driving condition, acquire a road surface gradient, a regenerative braking torque, and a wheel speed difference between front and rear wheels using at least one of a navigation device and a sensing device; determine a score of each of the road surface gradient, the regenerative braking torque, and the wheel speed difference between front and rear wheels, calculate a first operation score, and cause the disconnect device to engage in response to determining that the calculated first operation score is greater than or equal to a first reference score.

2. The control device for the disconnect device of an electric vehicle according to claim 1, wherein, The driving condition further includes a turning driving condition and a constant speed driving condition.

3. The control device for the disconnect device of an electric vehicle according to claim 2, wherein, The processor is configured to: when the driving condition is the turning driving condition, acquire a steering angle, a steering angular velocity, and a yaw rate error of the vehicle using at least one of the navigation device and the sensing device; determine a score of each of the steering angle, the steering angular velocity, and the yaw rate error of the vehicle, calculate a second operation score, and cause the disconnect device to engage in response to determining that the calculated second operation score is greater than or equal to a second reference score.

4. The control device for the disconnect device of an electric vehicle according to claim 2, wherein, The processor is configured to, when the driving condition is the constant speed driving condition, determine whether a speed difference between a constant speed driving vehicle speed and a first reference vehicle speed or a speed difference between the constant speed driving vehicle speed and a second reference vehicle speed is within a critical vehicle speed range.

5. The control device for the disconnect device of an electric vehicle according to claim 4, wherein, The processor is configured to, in response to determining that the speed difference between the constant speed driving vehicle speed and the first reference vehicle speed is within the critical vehicle speed range, perform a regulation to decrease the first reference vehicle speed based on an initial value of the first reference vehicle speed, a constant speed maintaining time, and a constant speed maintaining speed.

6. The control device for the disconnect device of an electric vehicle according to claim 4, wherein, The processor is configured to, in response to determining that the speed difference between the constant speed driving vehicle speed and the second reference vehicle speed is within the critical vehicle speed range, perform a regulation to increase the second reference vehicle speed based on an initial value of the second reference vehicle speed, a constant speed maintaining time, and a constant speed maintaining speed.

7. The control device for the disconnect device of an electric vehicle according to claim 4, wherein, The processor is configured to: in response to determining that the constant speed driving vehicle speed is greater than the first reference vehicle speed and less than or equal to the second reference vehicle speed, and a difference between a constant speed driving torque and a reference torque is within a critical torque range, acquire an initial value of the reference torque, a variation frequency of a required torque, and a high required torque maintaining time in a medium speed range; perform a regulation to decrease the reference torque based on the initial value of the reference torque, the variation frequency of the required torque, and the high required torque maintaining time in the medium speed range. 8.A control method of a disconnect device for an electric vehicle, comprising: identifying, by a processor, a driving condition of the vehicle; acquiring, by the processor, at least one factor related to an operation of the disconnect device in the driving condition; determining, by the processor, an operation mode of the disconnect device based on the at least one factor; operating the disconnection device according to the determination by the processor, wherein the driving condition includes a downhill driving condition, when the downhill driving condition is identified as the driving condition, acquiring at least one factor includes: acquiring, by using at least one of the navigation device and the sensing device, a road surface slope, a regenerative braking torque, and a wheel speed difference between front wheels and rear wheels, the determination of the operation mode of the disconnection device includes: determining, by the processor, a score of each of the road surface slope, the regenerative braking torque, and the wheel speed difference between front wheels and rear wheels to calculate a first operation score; comparing, by the processor, the first operation score with a first reference score; determining, by the processor, engagement of the disconnection device when the calculated first operation score is greater than or equal to the first reference score.

9. The control method of the disconnecting device for an electric vehicle according to claim 8, wherein, The driving condition further includes a turning driving condition and a constant speed driving condition.

10. The control method of the disconnecting device for an electric vehicle according to claim 9, wherein, Acquiring at least one factor includes: when the turning driving condition is identified as the driving condition, acquiring, by using at least one of the navigation device and the sensing device, a steering angle, a steering angular velocity, and a yaw rate error of the vehicle.

11. The control method of the disconnecting device for an electric vehicle according to claim 10, wherein, Determining the operation mode of the disconnection device includes: determining, by the processor, a score of each of the steering angle, the steering angular velocity, and the yaw rate error of the vehicle to calculate a second operation score; comparing, by the processor, the second operation score with a second reference score; determining, by the processor, engagement of the disconnection device in response to determining that the calculated second operation score is greater than or equal to the second reference score.

12. The control method of the disconnecting device for an electric vehicle according to claim 9, wherein, Acquiring at least one factor includes: when the constant speed driving condition is identified as the driving condition, determining, by the processor, whether a speed difference between a constant speed driving vehicle speed and a first reference vehicle speed is within a critical vehicle speed range; determining, by the processor, whether a speed difference between the constant speed driving vehicle speed and a second reference vehicle speed is within the critical vehicle speed range; acquiring, by the processor, an initial value of the first reference vehicle speed or the second reference vehicle speed, a constant speed maintaining time, and a constant speed maintaining speed when the speed difference between the constant speed driving vehicle speed and the first reference vehicle speed or the speed difference between the constant speed driving vehicle speed and the second reference vehicle speed is within the critical vehicle speed range.

13. The control method of the disconnecting device for an electric vehicle according to claim 12, wherein, Determining the operation mode of the disconnection device includes: in response to determining that the speed difference between the constant speed driving vehicle speed and the first reference vehicle speed is within the critical vehicle speed range, performing, by the processor, a regulation of decreasing the first reference vehicle speed based on the initial value of the first reference vehicle speed, the constant speed maintaining time, and the constant speed maintaining speed; determining, by the processor, engagement or disengagement of the disconnection device based on the regulated first reference vehicle speed.

14. The control method of the disconnecting device for an electric vehicle according to claim 12, wherein, Determining the operation mode of the disconnection device includes: in response to determining that the speed difference between the constant speed driving vehicle speed and the second reference vehicle speed is within the critical vehicle speed range, performing, by the processor, a regulation of increasing the second reference vehicle speed based on the initial value of the second reference vehicle speed, the constant speed maintaining time, and the constant speed maintaining speed; determining, by the processor, engagement or disengagement of the disconnection device based on the regulated second reference vehicle speed.

15. The control method of the disconnecting device for an electric vehicle according to claim 12, wherein, Acquiring at least one factor includes: when the uniform running condition is identified as the running condition, in response to determining that the uniform running vehicle speed is greater than the first reference vehicle speed and less than or equal to the second reference vehicle speed, determining, by the processor, whether a difference between the uniform running torque and the reference torque is within a critical torque range; in response to determining that the difference between the uniform running torque and the reference torque is within the critical torque range, acquiring, by the processor, an initial value of the reference torque, a change frequency of the required torque, and a high required torque holding time in the medium speed range.

16. The control method of the disconnecting device for an electric vehicle according to claim 15, wherein, The determination of the operation mode of the disconnection device includes: performing adjustment of reducing the reference torque based on the initial value of the reference torque, the change frequency of the required torque, and the high required torque holding time in the medium speed range.

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