KR20230142007A - Vehicle, controlling method of vehicle - Google Patents

Abstract

A vehicle according to an embodiment includes a drive motor that drives a drive wheel by applying torque, a battery that is electrically connected to the drive motor and is charged through regenerative braking when a torque in the opposite direction of driving is applied to the drive motor, and a battery of the drive motor. When a failure is detected, it includes a processor that calculates the insufficient deceleration required for the regenerative braking and performs hydraulic braking based on the braking torque caused by the insufficient deceleration, minimizing the driver's discomfort by utilizing hydraulic pressure in the event of a drive motor failure. We can help with stopping.

Description

Vehicles and vehicle control methods {VEHICLE, CONTROLLING METHOD OF VEHICLE}

The disclosed invention relates to a vehicle and a method for controlling the vehicle, and to a method for operating vehicle brakes in the event of a motor failure.

An electric vehicle refers to a vehicle that drives a motor using electrical energy stored in a battery and uses the driving force of the motor as a power source for all or part of the vehicle.

Recently, technology has been developed to recover energy through regenerative braking and simultaneously generate braking force for vehicles.

However, if regenerative braking is not performed due to a breakdown of the electric vehicle, there is a problem in that the braking force desired by the user cannot be provided to the vehicle.

One aspect of the disclosed invention seeks to provide a vehicle and a vehicle control method for operating the brakes using hydraulic pressure when regenerative braking is not performed due to a breakdown of the electric vehicle.

A vehicle according to an embodiment includes a drive motor that drives a drive wheel by applying torque, a battery that is electrically connected to the drive motor and is charged through regenerative braking when a torque in the opposite direction of driving is applied to the drive motor, and the drive motor. When a failure is detected, it may include a processor that calculates the insufficient deceleration required for the regenerative braking and performs hydraulic braking based on the braking torque caused by the insufficient deceleration.

The processor may determine that the drive motor has failed if the motor torque of the drive motor is less than the motor command of the drive motor.

The processor may calculate the required power for braking of the vehicle based on the difference between the power generated by the vehicle and the load applied to the vehicle, and calculate the under-deceleration based on the required power.

The processor derives the power generated by the vehicle based on the torque value preset for the vehicle and the accompanying radius of the driving wheel, and derives the load applied to the vehicle based on the slope of the road on which the vehicle travels. Thus, the under-deceleration can be calculated.

The processor may derive the predicted deceleration based on the required power and the weight of the vehicle, and calculate the under-deceleration based on the predicted deceleration and the actual measured deceleration measured by the vehicle.

The processor may calculate the braking torque required for braking of the vehicle based on the under-deceleration and the weight of the vehicle, and may perform hydraulic braking based on the braking torque.

The vehicle according to one embodiment may further include a display that displays a warning message and a communication unit that communicates with the server.

When a failure of the driving motor is detected, the processor may display a warning message regarding the failure of the driving motor on the display and control the communication unit to transmit a warning message to the server.

A vehicle control method according to an embodiment includes a vehicle electrically connected to a drive motor that drives a drive wheel by applying torque, and a battery that is charged through regenerative braking when torque in the opposite direction of driving is applied to the drive motor. In this case, when a failure of the drive motor is detected, the insufficient deceleration required for regenerative braking can be calculated, and hydraulic braking can be performed based on the braking torque caused by the insufficient deceleration.

Failure of the driving motor can be determined if the motor torque of the driving motor is smaller than the motor command of the driving motor.

Calculating the insufficient deceleration may calculate the required power for braking of the vehicle based on the difference between the power generated by the vehicle and the load applied to the vehicle, and calculate the insufficient deceleration based on the required power. there is.

Calculating the under-deceleration involves deriving the power generated by the vehicle based on the torque value preset for the vehicle and the accompanying radius of the driving wheel, and applying power to the vehicle based on the slope of the road on which the vehicle travels. The under-deceleration can be calculated by deriving the load.

In calculating the insufficient deceleration, the predicted deceleration can be derived based on the required power and the weight of the vehicle, and the insufficient deceleration can be calculated based on the predicted deceleration and the actual measured deceleration measured by the vehicle.

When performing the hydraulic braking, the braking torque required for braking the vehicle may be calculated based on the under-deceleration and the weight of the vehicle, and hydraulic braking may be performed based on the braking torque.

The vehicle control method according to one embodiment may further include displaying a warning message regarding the failure of the drive motor on the display when a failure of the drive motor is detected.

The vehicle control method according to one embodiment may further include controlling the communication unit to transmit a warning message to the server when a failure of the drive motor is detected.

According to one aspect of the vehicle and vehicle control method, in the event of a motor failure, hydraulic brakes can be used to help stop the vehicle while minimizing the driver's sense of discomfort, and in a motor failure situation, the driver may feel a sense of deceleration that does not match the existing paddle speed. Because it feels different, it is possible to stop with the same sense of deceleration as before by using hydraulic pressure.

Figure 1 is a diagram showing a control block diagram of a vehicle according to one embodiment.
Figure 2 is a diagram for explaining regeneration and regenerative braking of a vehicle according to an embodiment.
Figure 3 is a deceleration graph for each driving mode of a vehicle according to an embodiment.
Figure 4 is a diagram showing vehicle control when the drive motor is in a normal state in a vehicle according to one embodiment.
Figure 5 is a diagram showing vehicle control when a drive motor is in a failure state in a vehicle according to one embodiment.
Figure 6 is a diagram showing that when the drive motor is in a faulty state in a vehicle according to one embodiment, the processor utilizes a hydraulic brake to perform the same control as when the drive motor is in a normal state.
Figure 7 is a diagram showing deceleration torque for each driving mode in a vehicle according to an embodiment.
Figure 8 is a diagram showing an external load applied to a vehicle according to one embodiment.
Figure 9 is a diagram showing a control flowchart of a vehicle according to an embodiment.
Figure 10 is a diagram continuing to show a control flowchart of a vehicle according to one embodiment.

The embodiments described in this specification and the configuration shown in the drawings are preferred examples of the disclosed invention, and at the time of filing this application, there may be various modifications that can replace the embodiments and drawings in this specification.

In addition, the same reference numbers or symbols shown in each drawing of this specification indicate parts or components that perform substantially the same function.

Additionally, the terms used herein are used to describe embodiments and are not intended to limit and/or limit the disclosed invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “comprise,” “provide,” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification. It does not exclude in advance the existence or addition of other features, numbers, steps, operations, components, parts, or combinations thereof.

In addition, terms including ordinal numbers such as “first”, “second”, etc. used in this specification may be used to describe various components, but the components are not limited by the terms, and the terms It is used only for the purpose of distinguishing one component from another. For example, a first component may be named a second component without departing from the scope of the present invention, and similarly, the second component may also be named a first component. The term “and/or” includes any of a plurality of related stated items or a combination of a plurality of related stated items.

Additionally, terms such as "~unit", "~unit", "~block", "~member", and "~module" may refer to a unit that processes at least one function or operation. For example, the terms refer to at least one hardware such as a field-programmable gate array (FPGA)/application specific integrated circuit (ASIC), at least one software stored in the memory 300, or at least one processed by the processor 100. It can mean the process of .

The codes attached to each step are used to identify each step, and these codes do not indicate the order of each step. Each step is performed differently from the specified order unless a specific order is clearly stated in the context. It can be.

Meanwhile, the disclosed embodiments may be implemented in the form of a recording medium that stores instructions executable by a computer. Instructions may be stored in the form of program code and, when executed by the processor 100, may perform the operations of the disclosed embodiments. The recording medium may be implemented as a computer-readable recording medium.

Computer-readable recording media include all types of recording media storing instructions that can be decoded by a computer. For example, there may be Read Only Memory (ROM), Random Access Memory (RAM), magnetic tape, magnetic disk, flash memory 300, optical data storage device, etc.

Hereinafter, embodiments of the vehicle 1 and a control method of the vehicle 1 according to one aspect will be described in detail with reference to the attached drawings.

The present invention relates to a vehicle and a method for controlling the vehicle, and more specifically, to a method for operating the brake 500 using hydraulic pressure when regenerative braking is not performed due to a breakdown of the electric vehicle.

Figure 1 is a diagram showing a control block diagram of a vehicle according to one embodiment.

Referring to Figure 1, the vehicle 1 according to one embodiment includes a communication unit 200, a memory 300, a display 400, a brake 500, and a processor 100 that controls the above-described components. .

The communication unit 200 can communicate with the server 600 to notify of a failure of the driving motor 13, and various communication methods can be used.

For example, the communication unit 200 uses second generation (2G) communication methods such as Time Division Multiple Access (TDMA) and Code Division Multiple Access (CDMA), and broadband code. 3rd generation (3G) communication methods such as Wide Code Division Multiple Access (WCDMA), Code Division Multiple Access 2000 (CDMA2000), Wireless Broadband (Wibro), and World Interoperability for Microwave Access (WiMAX), 4th generation (4G) communication methods such as Long Term Evolution (LTE) and Wireless Broadband Evolution can be adopted. The communication unit 200 may adopt a 5th generation (5G) communication method.

The communication unit 200 may include one or more components that enable communication with an external device, and may include, for example, at least one of a short-range communication module, a wired communication unit 220, and a wireless communication unit 210.

The short-range communication module transmits signals using a wireless communication network at a short distance, such as a Bluetooth module, infrared communication module, RFID (Radio Frequency Identification) communication module, WLAN (Wireless Local Access Network) communication module, NFC communication module, and Zigbee communication module. It may include various short-range communication modules that transmit and receive.

The wired communication unit 220 is a Controller Area Network (CAN) communication module, a Local Area Network (LAN) module, a Wide Area Network (WAN) module, or a Value Added Network (VAN) module, etc. In addition to various wired communication units 220 and 132, USB (Universal Serial Bus), HDMI (High Definition Multimedia Interface), DVI (Digital Visual Interface), RS-232 (recommended standard 232), power line communication, or POTS (plain old) It may include various cable communication modules such as telephone service).

The wireless communication unit 210 includes Radio Data System-Traffic Message Channel (RDS-TMC), Digital Multimedia Broadcasting (DMB), Wi-Fi module, and Wireless broadband module, as well as GSM (global) Various wireless communication methods such as System for Mobile Communication), CDMA (Code Division Multiple Access), WCDMA (Wideband Code Division Multiple Access), UMTS (universal mobile telecommunications system), TDMA (Time Division Multiple Access), and LTE (Long Term Evolution) It may include a wireless communication unit 210 that supports.

The wireless communication unit 210 may include a wireless communication interface including an antenna and a transmitter for transmitting a warning message to the server 600. Additionally, the wireless communication unit 210 may further include a signal conversion module for demodulating an analog wireless signal received through a wireless communication interface into a digital control signal.

The communication unit 200 may transmit a warning message containing information about a motor failure of the vehicle 1 to the external server 600, and the external server 600 may transmit a warning message based on the warning message received from the communication unit 200. The fact that the vehicle (1) has broken down can be notified to an external organization.

For example, the external server 600 may notify the maintenance facility of the vehicle 1 of the fact that the vehicle 1 has broken down, or may notify the user terminal of the owner of the vehicle 1.

Specifically, based on the warning message, the external server 600 may transmit a message stating that maintenance is necessary because there is a problem with the motor of the vehicle 1 to the vehicle 1 maintenance facility or the user terminal of the vehicle 1 owner. .

Accordingly, when the vehicle 1 according to one embodiment detects a situation in which the hydraulic brake 500 must operate due to a motor failure, it communicates with the external server 600 to receive maintenance as soon as possible. There is.

The memory 300 includes volatile memory 300 such as Static Random Access Memory (S-RAM) and Dynamic Random Access Memory (D-RAM), Read Only Memory (ROM), It may include a non-volatile memory 300 such as Erasable Programmable Read Only Memory (EPROM). The memory 300 may include one memory 300 element or may include a plurality of memory 300 elements.

The memory 300 may store the torque value preset in the vehicle 1 to calculate the under-deceleration based on the required power.

In this regard, the processor 100 calculates the required power for braking of the vehicle 1 based on the difference between the power generated by the vehicle 1 and the load applied to the vehicle 1, and determines the shortage based on the required power. Speed can be calculated.

Here, the processor 100 can derive the power generated by the vehicle 1 based on the torque value preset for the vehicle 1 and the accompanying radius of the driving wheel 14. At this time, the torque value preset for the vehicle 1 may be stored in the memory 300.

That is, the processor 100 calculates the power generated by the vehicle 1 by multiplying the torque value pre-stored in the memory 300 by the accompanying diameter of the drive wheel 14, and calculates the power generated by the vehicle 1 and the vehicle ( The power required for braking of the vehicle (1) can be calculated from the difference in load applied to 1).

Afterwards, the processor 100 calculates the predicted deceleration by dividing the power required for braking of the vehicle 1 by the weight of the vehicle 1, and calculates the predicted deceleration from the vehicle 1's controller (Vehicle Control Unit, VCU). The under-deceleration can be calculated from the difference between the detected actual deceleration.

The processor 100 multiplies the under-deceleration by the weight of the vehicle 1 to derive the braking torque, and operates the hydraulic brake 500 as much as the braking torque to stop the vehicle 1 while minimizing the driver's discomfort.

In the conventional technology, when the motor of the vehicle 1 breaks down, the driver who feels a sense of discomfort must directly apply the brake 500. However, since the amount of operation of the brake 500 is not constant for each driver, this may impede the riding comfort and cause sudden braking. There was a problem that the operation of (500) caused an accident with the following vehicle (1).

On the other hand, in the vehicle 1 according to one embodiment, even if the motor of the vehicle 1 breaks down, the processor 100 operates the hydraulic brake 500 by the amount of braking torque required for regenerative braking, thereby minimizing the driver's discomfort and causing accidents. It is effective in preventing.

The display 400 may display a warning message regarding a malfunction of the vehicle 1 or a notification regarding intervention of the hydraulic brake 500.

The display 400 may include an Audio Video Navigation (AVN) display 400. However, in this embodiment, the output unit that displays warning messages and notifications is not necessarily limited to the AVN display 400.

Even if the display 400 is not an AVN display 400, it can be a display 400 that displays a notification if the user riding in the vehicle 1 can check the displayed content.

For example, the display 400 may be a speaker inside the vehicle 1 that outputs sound.

In addition, the display 400 displays information indicating the status of the vehicle 1, displays information to guide the settings of the vehicle 1, displays a navigation screen, displays multimedia content, or provides driving and Related information can also be displayed.

The vehicle 1 according to one embodiment may include an actuator (not shown) and a brake 500, and the actuator may be a hydraulic braking actuator.

The brake 500 may include at least one brake caliper, and each caliper may include a pair of brake pads provided on both sides of the brake disc.

A pair of brake pads can be pressed against the brake disc from either side of the brake disc by hydraulic or mechanical pressure, for example by the actuator.

Ultimately, the rotation of the wheels may be stopped due to friction between the brake pad and the brake disc, and when the motor fails in the vehicle 1 according to one embodiment, the brake 500 operated by the processor 100 is a hydraulic brake. It may be (500).

Figure 2 is a diagram for explaining regeneration and regenerative braking of a vehicle according to an embodiment.

Referring to Figure 2, the vehicle 1 may be composed of a driving wheel 14, a driving motor 13, an inverter 12, and a battery 11 for regenerative braking.

Regenerative braking can also be expressed as regenerative charging. Regenerative charging refers to converting kinetic energy into electrical energy and storing it using the resistance of the motor when the vehicle (1) decelerates by applying the brake (500), driving downhill, or being towed by the towing vehicle (1). It may be a charging method.

When torque is applied by the drive motor 13, the drive wheel 14 supports the ground and can rotate so that the vehicle 1 moves forward or backward.

The torque applied to the driving wheel 14 may be in the first direction 16 and the second direction 15, and the first direction 16 and the second direction 15 correspond to the forward and backward directions. Rather, it is a concept that corresponds to the direction of torque.

That is, when the vehicle 1 is traveling in the forward direction, if torque is applied to the driving wheel 14 in the first direction 16, the vehicle 1 can continue to travel in the forward direction and the driving wheel 14 When torque is applied in the second direction 15, the vehicle 1 may travel in the forward direction and the traveling speed may decrease.

Similarly, when the vehicle 1 is traveling in the reverse direction, when torque is applied to the drive wheel 14 in the first direction 16, the vehicle 1 may travel in the reverse direction and the traveling speed may be reduced, and the driving wheel (14) may be reduced while driving in the reverse direction. When torque is applied to 14) in the second direction 15, the vehicle 1 can continue to travel in the reverse direction.

The drive motor 13 has a configuration corresponding to the engine of the vehicle 1 that uses electricity as fuel, and may be a motor-generator.

The drive motor 13 normally receives electrical energy and serves as a power source to transmit power to the drive wheel 14, but it can function as a generator when kinetic energy is applied from the outside.

The inverter 12 may be a device that receives power supplied from a commercial power source, changes the voltage and frequency within itself, and supplies it to an electric motor to control it so that the user can efficiently use the motor speed.

The battery 11 may be configured with high energy density to ensure sufficient driving range of the vehicle 1, and a battery management system may be applied to improve charging and discharging efficiency of the battery 11.

The motor of an electric vehicle is composed of a rotor and a stator, with the rotor being composed of a permanent magnet and the stator being composed of a coil.

When the drive wheel 14 rotates due to the inertia of the vehicle 1, the permanent magnet of the drive motor 13 rotates, and as the magnet of the drive motor 13 rotates, the N and S poles of the magnet are connected to the coil. You can repeat moving away and getting closer.

Accordingly, a current is generated in the coil, and the inverter 12 can charge the battery 11 by flowing the current in the direction of the battery 11.

The vehicle 1 according to one embodiment can generate braking force while utilizing regenerative charging as described above, and can be used like the brake 500.

However, if a failure occurs in the drive motor 13, regenerative braking may not be possible or a braking force that is weaker than the set braking force may be exerted, which may cause a different feeling regarding the deceleration force to the user.

Hereinafter, a process for generating the same deceleration force as braking by regenerative braking will be described even when the motor fails in the vehicle 1 according to one embodiment.

Figure 3 is a deceleration graph for each driving mode of the vehicle 1 according to an embodiment.

Referring to Figure 3, if a problem occurs in the motor itself or the motor-related system in the vehicle (1) and the motor is uncontrollable, the vehicle (1) must be stopped because the vehicle (1) cannot generate motor torque. .

At this time, if the motor does not produce the coasting torque to operate the regenerative braking during coasting, the driver may feel that the vehicle 1 is starting, and thus may feel a sense of heterogeneity related to deceleration.

In the vehicle 1 according to one embodiment, when the motor is uncontrollable, the processor 100 may stop the vehicle 1 by intervening hydraulic pressure.

That is, since the deceleration force that would have been provided through regenerative braking is not provided due to a motor failure, the processor 100 can control hydraulic braking to be equal to the deceleration force that would have been provided through regenerative braking.

Referring to Figure 3, the deceleration for each driving mode used in the vehicle 1 can be confirmed, and here the driving mode may be a level of regenerative braking.

In other words, the D0 level of regenerative braking is a level in which regenerative braking is not used, and the highest level, OPD (One Pedal Drive) level, is a mode in which charging due to deceleration is set to the maximum.

As the level of regenerative braking of the vehicle 1 increases, the charging amount increases and the braking force of the drive motor 13 increases.

Accordingly, the processor 100 can control the vehicle 1 to determine the driving mode, derive a braking torque that can be produced in the driving mode, and operate the hydraulic brake 500 corresponding to the braking torque.

Specifically, the processor 100 may determine the deceleration to be -0.025 m/s ² when the vehicle 1 is two-wheel drive (2WD) and the speed of the vehicle 1 is 20 km/h, and the driving mode is D0. If the driving mode is D1, the deceleration can be judged as -0.005m/s ² , if the driving mode is D2, the deceleration can be judged as -0.11m/s ² , and if the driving mode is D3, the deceleration can be judged as -0.11m/s 2 It can be judged as -0.16m/s ² , and if the driving mode is OPD, the deceleration can be judged as -0.2m/s ² .

In contrast, when the speed of the vehicle 1 is 100 km/h, the processor 100 may determine the deceleration to be -0.004 m/s ² if the driving mode is D0, and the deceleration may be determined to be -0.09 m if the driving mode is D1. /s ² , if the driving mode is D2, the deceleration can be judged as -0.14m/s ² , if the driving mode is D3, the deceleration can be judged as -0.175m/s 2 , and if the driving mode is D3, the deceleration can be judged as -0.175m/s ² If the mode is OPD, the deceleration can be determined to be -0.225m/s ² .

That is, the processor 100 may determine that as the speed of the vehicle 1 increases, the deceleration required for braking of the vehicle 1 also increases, and for braking of the vehicle 1 shown in FIG. 3 The required deceleration may be stored in advance in the memory 300.

Figure 4 is a diagram showing control of the vehicle 1 when the drive motor 13 in the vehicle 1 is in a normal state according to an embodiment.

In the vehicle 1 according to one embodiment, regenerative braking is performed as the accelerator opening amount (b) decreases, and the vehicle speed (a), deceleration (c), and motor torque (d) may change.

4 is a normal state in which no abnormality occurs in the motor, so when the driver takes his or her foot off the accelerator and the accelerator opening amount decreases, regenerative braking can be performed.

That is, as described above, the vehicle 1 coasts and the drive motor 13 is used as a generator for regenerative charging, and the braking force generated at this time can serve as the brake 500.

At this time, the accelerator opening amount (b) can be defined as the degree to which the fuel injection amount is adjusted according to the driver's accelerator stroke. The lower the accelerator opening amount (b), the lower the fuel injection amount, which may reduce the vehicle speed. there is.

Referring to Figure 4, the vehicle speed (a) of the vehicle 1 may decrease proportionally because regenerative braking is performed starting from the point when the accelerator opening amount (b) rapidly decreases. Specifically, when the accelerator opening amount (b) of the vehicle (1) decreases sharply around 75%, the amount of fuel injected into the engine decreases, and the vehicle speed (a), which increased to 100 km/h, may decrease proportionally. there is.

Additionally, the absolute value of the deceleration (c) of the vehicle 1 may increase starting from the point in time when the accelerator opening amount (b) decreases. Specifically, when the accelerator opening amount (b) of the vehicle 1 rapidly decreases around 75%, the absolute value of the deceleration (c) may increase from 0.2 m/s ² to 0.45 m/s ² . This increased deceleration c may result in braking of the vehicle 1.

The motor torque (d) of the vehicle (1) decreases starting from the point where the accelerator opening amount (b) decreases, thereby reducing the vehicle speed (a) and allowing regenerative braking to be performed. Specifically, when the accelerator opening amount (b) of the vehicle 1 decreases rapidly around 75%, the motor torque may decrease from 58 Nm to 10 Nm.

In this way, when the drive motor 13 is normal, the speed can be reduced to a level set by the manufacturer of the vehicle 1 so that the driver feels comfortable without any discomfort regarding the speed reduction.

Figure 5 is a diagram showing vehicle control when a drive motor is in a failure state in a vehicle according to one embodiment.

5 shows a state in which a problem has occurred in the motor, so even if the driver takes his or her foot off the accelerator and the accelerator opening decreases, regenerative braking may not be performed.

In other words, since the drive motor 13 cannot be used as a generator due to coasting, regenerative charging does not proceed and no braking force is generated at this time, so it cannot function as a brake 500.

Ultimately, the driver may feel that the vehicle 1 is moving compared to Figure 4, and there is a risk of an accident occurring due to a sudden stop due to the feeling of heterogeneity.

Continuing to refer to Figure 5, the driver may anticipate a decrease in the vehicle speed (a) of the vehicle 1 and take his or her foot off the accelerator, and thus the accelerator opening amount (b) may remain the same as in Figure 4.

The vehicle speed (a) of the vehicle (1) is decelerated only by forces applied to the outside of the vehicle (1), such as friction force or air resistance, without regenerative braking starting from the point when the accelerator opening amount (b) rapidly decreases. may decrease more slowly than in the normal state.

Specifically, when the accelerator opening amount (b) of the vehicle 1 suddenly decreases around 75%, the amount of fuel injected into the engine decreases, and the vehicle speed (a), which had increased to 100 km/h, may decrease. However, even at this time, since regenerative braking is not performed on the vehicle 1, the vehicle speed a may be reduced to a smaller slope compared to FIG. 4.

Additionally, the absolute value of the deceleration (c) of the vehicle 1 may increase starting from the point in time when the accelerator opening amount (b) decreases. Specifically, when the accelerator opening amount (b) of the vehicle 1 rapidly decreases around 75%, the absolute value of the deceleration (c) may increase from 0.2 m/s ² to 0.3 m/s ² .

However, since regenerative braking is not performed, the absolute value of deceleration (c) may decrease compared to when the motor is in a normal state. That is, the absolute value of deceleration c for decelerating the vehicle 1 is reduced compared to FIG. 4, so that the vehicle speed a of the vehicle 1 can be gently reduced.

The motor torque (d) of the vehicle 1 may decrease starting from the point at which the accelerator opening amount (b) decreases, thereby reducing the vehicle speed (a). Specifically, when the accelerator opening amount (b) of the vehicle 1 decreases rapidly around 75%, the motor torque may decrease from 70 Nm to 35 Nm.

However, even at this time, since regenerative braking is not involved, the motor torque can be maintained higher than in Figure 4.

In this way, when the drive motor 13 is in a faulty state, the speed may be decelerated more slowly than the driver feels comfortable with the deceleration.

Accordingly, the driver may feel a sense of heterogeneity and anxiety regarding the deceleration of the vehicle 1, so it is necessary to maintain appropriate braking force through the intervention of the hydraulic brake 500.

Figure 6 is a diagram showing that when a drive motor is in a faulty state in a vehicle according to an embodiment, a processor utilizes a hydraulic brake to perform the same control as when the motor is in a normal state.

Figure 6 shows that in a state in which a problem occurs in the motor, the hydraulic brake 500 is intervened, so that the vehicle speed can be normally reduced as shown in Figure 4.

In other words, since the drive motor 13 is not used as a generator due to coasting, regenerative charging does not proceed and regenerative braking force is not generated, but insufficient braking force can be provided by the hydraulic brake 500 by calculating the regenerative braking force at this time. there is.

In the end, compared to Figure 5, the driver does not feel that the vehicle 1 is moving and does not feel strange, so accidents due to sudden stops, etc. can be prevented.

Continuing to refer to Figure 6, the driver may anticipate a decrease in the vehicle speed (a) of the vehicle 1 and take his or her foot off the accelerator, and thus the accelerator opening amount (b) may remain the same as in Figures 4 and 5. there is.

Regenerative braking is not performed on the vehicle speed (a) of the vehicle (1) starting from the point when the accelerator opening amount (b) rapidly decreases, but the processor 100 compensates by adding braking force with the hydraulic brake 500, so the motor The vehicle speed (a) may decrease as in the normal state.

Specifically, when the accelerator opening amount (b) of the vehicle (1) decreases sharply around 75%, the amount of fuel injected into the engine decreases, and the vehicle speed (a), which increased to 100 km/h, may decrease proportionally. there is.

Additionally, the absolute value of the deceleration (c) of the vehicle 1 may increase starting from the point in time when the accelerator opening amount (b) decreases. Specifically, when the accelerator opening amount (b) of the vehicle 1 rapidly decreases around 75%, the absolute value of the deceleration (c) may increase from 0.2 m/s ² to 0.45 m/s ² . This increased deceleration c may result in braking of the vehicle 1.

The motor torque (d) of the vehicle 1 may decrease starting from the point at which the accelerator opening amount (b) decreases, thereby reducing the vehicle speed (a). Specifically, when the accelerator opening amount (b) of the vehicle 1 decreases rapidly around 75%, the motor torque may decrease from 70 Nm to 30 Nm.

However, even at this time, since regenerative braking is not involved, the motor torque can be maintained higher than in Figure 4.

Since regenerative braking is not performed in the vehicle 1 according to one embodiment, insufficient braking force can be compensated for by adding the hydraulic brake 500.

That is, the processor 100 detects a motor failure at the point when the accelerator opening amount decreases, and when it is determined that a motor failure has occurred, the processor 100 can calculate the insufficient deceleration required for regenerative braking.

Thereafter, the processor 100 may calculate the braking torque due to insufficient deceleration and perform hydraulic braking corresponding to the calculated braking torque to correct the braking force.

Figure 7 is a diagram showing deceleration torque for each driving mode in a vehicle according to an embodiment.

Referring to FIG. 7 , the processor 100 may calculate the insufficient deceleration based on the deceleration torque preset for the vehicle 1.

The processor 100 may calculate the power required for braking of the vehicle 1 based on the difference between the power generated by the vehicle 1 and the load applied to the vehicle 1.

That is, the processor 100 excludes external forces such as friction, air resistance, gravity, etc. applied to the vehicle 1 from the power of the drive motor 13 generated by the driver's operation of the vehicle 1 and The remaining force can be calculated.

At this time, the processor 100 may determine the remaining power in the vehicle 1 as the necessary power for braking the vehicle 1. Specifically, the processor 100 may calculate the power required for braking of the vehicle 1 by dividing the braking torque value preset in FIG. 7 by the accompanying radius of the driving wheel 14.

Thereafter, the processor 100 can calculate the load applied to the vehicle 1 when climbing the slope of the road on which the vehicle 1 is traveling as shown in FIG. 8, which will be described later.

The processor 100 may derive the predicted deceleration by dividing the calculated required power by the weight of the vehicle 1. That is, the processor 100 can derive the predicted deceleration, which is the deceleration required for stopping, by dividing the remaining force in the vehicle 1 by the weight.

The processor 100 can calculate the insufficient deceleration by excluding the actual deceleration detected by the vehicle control unit (VCU) of the vehicle 1 from the derived predicted deceleration.

The processor 100 may calculate the braking torque required for braking the vehicle 1 by multiplying the under-deceleration by the weight of the vehicle 1 and the accompanying diameter of the driving wheel 14.

That is, the processor 100 can directly calculate the braking force that regenerative braking could not generate due to a motor failure, and define this as braking torque.

Specifically, in FIG. 7, in order to calculate the insufficient deceleration, when the speed of the vehicle 1 is 10 kph, the processor 100 sets the deceleration torque to -10 Nm when the driving mode is D0 and the deceleration torque to -10 Nm when the driving mode is D1. With -300Nm, the deceleration torque can be used as -600Nm when the operation mode is D2, and the deceleration torque can be used as -900Nm when the operation mode is D3.

In addition, in order to calculate the insufficient deceleration, the processor 100 sets the deceleration torque to -10Nm when the driving mode is D0 when the speed of the vehicle 1 is 150kph, and sets the deceleration torque to -600Nm when the driving mode is D1. When the mode is D2, the deceleration torque is -1300Nm, and when the operation mode is D3, the deceleration torque is -2000Nm, so the deceleration torque can be used differently depending on the speed.

For a specific example, when the current speed of the vehicle 1 is 10 kph and the driving mode is D0, the processor 100 converts the power generated by the vehicle 1 to (-10/co-radius of the drive wheel 14). It can be calculated.

Afterwards, the processor 100 calculates the required power for braking of the vehicle 1 by excluding the load applied to the vehicle 1 from the power generated by the vehicle 1, and calculates the under-deceleration as described above. Braking torque can be calculated.

Similarly, when the current speed of the vehicle 1 is 150 kph and the driving mode is D3, the processor 100 can calculate the power generated by the vehicle 1 as (-2000/co-radius of the driving wheel 14).

Figure 8 is a diagram for explaining the load received when the towing vehicle 1 climbs a hill according to an embodiment.

Referring to FIG. 8, the load (Ft) applied to the vehicle 1 when the vehicle 1 travels at the inclination angle θ can be obtained as shown in FIG. 8.

The processor 100 calculates the air resistance force (Fd) received when the vehicle 1 climbs the incline angle as shown in Equation 1,

[Equation 1]

The processor 100 calculates the rolling resistance (Fr) received when the wheels of the vehicle 1 are driven as shown in Equation 2,

[Equation 2]

The processor 100 can calculate the climbing force (Fg) received when the vehicle 1 climbs the incline angle as shown in Equation 3.

[Equation 3]

Through this, the processor 100 can calculate the load (Ft) that the vehicle 1 receives while driving on the slope as shown in Equation 4.

[Equation 4]

At this time, Wt is the weight of the vehicle (1), g is the weight acceleration, θ is the inclination angle, A _f is the front area of the vehicle (1), p is the air density, C _d is the drag coefficient, C _r is the rolling resistance, I is the moment of inertia, r is the accompanying diameter of the drive wheel 14, and K is the resistance correction coefficient.

The processor 100 can calculate the load applied to the vehicle 1 as above, and the processor 100 excludes the load applied to the vehicle 1 from the power generated by the vehicle 1 to calculate the load applied to the vehicle 1. The braking torque can be calculated by calculating the required power for braking and calculating the under-deceleration.

As described in FIGS. 7 and 8, the processor 100 can calculate the braking torque by calculating the power generated by the vehicle 1 and the load applied to the vehicle 1, and the calculated braking torque is used to apply a hydraulic brake ( 500) can be operated.

Figures 9 and 10 are diagrams showing a control flowchart of a vehicle according to an embodiment.

Referring to FIG. 9, the processor 100 of the vehicle 1 according to one embodiment may determine whether there is a problem with the motor while the vehicle 1 is running (900). At this time, the processor 100 can determine whether there is a problem with the motor not only while the vehicle 1 is running but also while the vehicle 1 is stopped.

At this time, when the processor 100 detects a failure of the driving motor 13, it displays a warning message regarding the failure of the driving motor 13 on the display 400 and controls the communication unit 200 to send the external server 600. A warning message can be sent to .

Afterwards, if the processor 100 determines that regenerative braking is not possible due to a motor problem (example of 910), the processor 100 may compare the size of the motor command and the motor torque (920).

If the motor command is smaller than the motor torque, the processor 100 may determine that regenerative braking is not possible due to a motor failure and additional braking force is required (example 920).

However, even if it is determined that regenerative braking is not possible, the processor 100 may not calculate the insufficient deceleration if the motor command is not smaller than the motor torque due to the slope of the hill or air resistance, etc. (No in 920).

Thereafter, the processor 100 may calculate the under-deceleration required by regenerative braking (930). The processor 100 may calculate the under-deceleration based on the power generated by the vehicle 1 and the load applied to the vehicle 1.

Continuing to refer to FIG. 10, the processor 100 may determine whether the calculated insufficient deceleration satisfies the required deceleration (1000).

That is, the processor 100 can determine whether the size of the insufficient deceleration corresponds to a required deceleration that is greater than a preset standard, and if the required deceleration is satisfied, the processor 100 can calculate the required torque, which is the braking torque required for stopping (1010).

Thereafter, the processor 100 may issue a torque command to the hydraulic brake 500 based on the calculated braking torque (1020).

Accordingly, the vehicle 1 according to one embodiment compensates for the insufficient braking torque due to motor failure with the hydraulic brake 500, which has the effect of helping the driver stop while minimizing the driver's sense of discomfort.

Since the control method of the vehicle 1 according to one embodiment overlaps with the vehicle 1 according to one embodiment, description thereof is omitted.

As described above, the disclosed embodiments have been described with reference to the attached drawings. A person skilled in the art to which the present invention pertains will understand that the present invention can be practiced in forms different from the disclosed embodiments without changing the technical idea or essential features of the present invention. The disclosed embodiments are illustrative and should not be construed as limited to specific embodiments.

1: vehicle
100: processor
200: Communication Department, 210: Wireless Communication Department, 220: Wired Communication Department
300: memory
400: display
500: brake
600: Server

Claims (16)

A drive motor that applies torque to drive the drive wheel;
a battery that is electrically connected to the drive motor and charged through regenerative braking when a torque in the opposite direction is applied to the drive motor; and
A vehicle comprising: a processor that calculates the under-deceleration required for the regenerative braking when a failure of the drive motor is detected, and performs hydraulic braking based on the braking torque caused by the under-deceleration. According to paragraph 1,
The processor,
A vehicle that determines that the drive motor has failed when the motor torque of the drive motor is less than the motor command of the drive motor. According to paragraph 1,
The processor,
A vehicle that calculates the required power for braking of the vehicle based on the difference between the power generated by the vehicle and the load applied to the vehicle, and calculates the insufficient deceleration based on the required power. According to paragraph 3,
The processor,
Derive the power generated by the vehicle based on the torque value preset for the vehicle and the accompanying radius of the driving wheel,
A vehicle that calculates the under-deceleration by deriving the load applied to the vehicle based on the slope of the road on which the vehicle travels. According to paragraph 3,
The processor,
A vehicle that derives a predicted deceleration based on the required power and the weight of the vehicle, and calculates the under-deceleration based on the predicted deceleration and an actual deceleration measured by the vehicle. According to clause 5,
The processor,
A vehicle that calculates the braking torque required to brake the vehicle based on the under-deceleration and the weight of the vehicle, and performs hydraulic braking based on the braking torque. According to paragraph 1,
A display that displays a warning message; and
A vehicle further comprising a communication unit that communicates with the server. In clause 7,
The processor,
A vehicle that, when a failure of the drive motor is detected, displays a warning message regarding the failure of the drive motor on the display and controls the communication unit to transmit a warning message to the server. In a vehicle equipped with a battery that is electrically connected to a drive motor that applies torque to drive the drive wheels and is charged through regenerative braking when a torque in the opposite direction of driving is applied to the drive motor,
When a failure of the drive motor is detected, calculate the insufficient deceleration required for regenerative braking;
A vehicle control method that performs hydraulic braking based on braking torque due to the insufficient deceleration. According to clause 9,
Determining the failure of the driving motor is,
A vehicle control method that determines that the drive motor has failed when the motor torque of the drive motor is less than the motor command of the drive motor. According to clause 9,
To calculate the under-deceleration,
A vehicle control method that calculates the required power for braking of the vehicle based on the difference between the power generated by the vehicle and the load applied to the vehicle, and calculates the insufficient deceleration based on the required power. According to clause 11,
To calculate the under-deceleration,
Derive the power generated by the vehicle based on the torque value preset for the vehicle and the accompanying radius of the driving wheel,
A vehicle control method for calculating the under-deceleration by deriving the load applied to the vehicle based on the slope of the road on which the vehicle travels. According to clause 11,
To calculate the under-deceleration,
A vehicle control method for deriving a predicted deceleration based on the required power and the weight of the vehicle, and calculating the under-deceleration based on the predicted deceleration and an actual deceleration measured by the vehicle. According to clause 13,
Performing the hydraulic braking,
A vehicle control method that calculates the braking torque required for braking of the vehicle based on the under-deceleration and the weight of the vehicle, and performs hydraulic braking based on the braking torque. According to clause 9,
When a failure of the drive motor is detected, displaying a warning message regarding the failure of the drive motor on the display. According to clause 9,
When a failure of the drive motor is detected, controlling the communication unit to transmit a warning message to the server.

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