Method for controlling the pitch of an electric vehicle based on motor vibrations

Abstract

A method for controlling the tone of an electric vehicle based on motor vibration includes: calculating order components from vibration signals of a rotating motor of the electric vehicle (EV); and extracting components with deterministic coefficients R. 2 The Nth order component, the coefficient of determination R 2 It represents a linear relationship with respect to the output torque of the motor and is greater than or equal to a predetermined value; it converts the RPM of the motor into a frequency and calculates the order frequency; it arranges the order components by applying the vibration level of the Nth order component to the level of the order frequency to be output, and sets the EV mode tone; and when the EV decelerates, it determines the deceleration conditions and applies the vibration level of the Nth order component to the level control of the order frequency.

Description

Technical Field

[0001] Exemplary embodiments of this disclosure relate to a method for controlling the tone of an electric vehicle (EV) based on motor vibration under deceleration or regenerative braking conditions. Background Technology

[0002] Recently, with the emergence of vehicles that do not produce engine noise (such as electric vehicles (EVs) that can run on all motors), there is a trend towards installing noise generators in environmentally friendly vehicles. Typically, noise from vehicles can cause discomfort to drivers and nearby pedestrians to some extent, and it also enhances pedestrians' ability to recognize surrounding vehicles through sight and hearing, thus playing a role in preventing traffic accidents.

[0003] Accordingly, tone control for EVs has been primarily developed for storing and playing back virtual sounds. This is because, unlike internal combustion engine vehicles, EVs are very quiet during acceleration and deceleration, and generate only high-frequency electromagnetic noise from within the EV itself.

[0004] Recent tone control technologies enhance driving pleasure for drivers through visual and auditory means, which are considered to improve vehicle marketability. Therefore, it is necessary to store and generate music or sounds suitable for EVs, and specifically, even control the tone during deceleration or regenerative braking. Summary of the Invention

[0005] Exemplary embodiments of this disclosure relate to a method for controlling the tone of an electric vehicle (EV) based on motor vibration under deceleration or regenerative braking conditions, the method performing tone control on the EV based on motor vibration of the EV which uses a motor as a power source.

[0006] The embodiments of this disclosure, as proposals, provide: a technique for controlling tone based on the characteristics of an electric vehicle (EV) motor that replaces the power of a conventional internal combustion engine, corresponding to the performance of the EV and being desired by the user; a technique for controlling EV tone that can extract in real time the order components of motor vibrations highly correlated with the motor output characteristics of the EV, which correspond to the power performance of an internal combustion engine, to achieve the desired sound of the internal combustion engine, which matches the power performance characteristics of the EV, and uses high-frequency characteristics to control ultra-modern sounds, and relates to a technique for controlling EV tone even during EV deceleration or regenerative braking.

[0007] Other advantages of this disclosure will become apparent from the following description, and will become apparent from embodiments thereof. Likewise, it will be apparent to those skilled in the art to which this disclosure pertains that the objects and advantages of this disclosure can be achieved by the claimed means and combinations thereof.

[0008] According to embodiments of this disclosure, a method for controlling the tone of an EV based on motor vibration under deceleration or regenerative braking conditions includes: calculating, by a vibration sensor signal processing controller, the order components of a vibration signal from a rotating motor of the EV; and extracting components with deterministic coefficients R from the calculated order components by the vibration sensor signal processing controller. 2 The Nth order component, the coefficient of determination R 2 The vibration sensor signal processing controller converts the EV's motor revolutions per minute (RPM) into frequency and calculates the order frequency, representing a linear relationship with the motor's output torque and greater than or equal to a predetermined value. The controller arranges the order components by applying the vibration level of the Nth order component to the level of the order frequency to be output, and sets the EV mode tone. Under EV deceleration conditions, deceleration conditions are determined and applied to the level control of the order frequency to set the EV mode tone. The EV mode tone with the deceleration intention applied is output, where the deceleration conditions are determined by driver braking and / or regenerative braking. Order analysis is used to quantify noise or vibration in rotating machinery where the rotational speed changes over time. The order frequency refers to a frequency that is a specific multiple of the reference rotational speed; the order corresponds to that specific multiple.

[0009] When the condition is determined to be deceleration, a fade-out algorithm can be used in the level control of the order frequency. The fade-out algorithm can use the product of deceleration weight values, which can be one or more of the following: the decrease in the RPM of the EV motor, the decrease in the opening of the accelerator pedal, the decrease in vehicle speed, and the increase in the braking force of the brake pedal.

[0010] The rearrangement of the order components can use indoor audio or indoor speakers to provide a deceleration notification sound to the driver, and the rearrangement of the order components can use outdoor speakers to provide a deceleration sound to protect pedestrians outside.

[0011] In addition to the vibration sensor signal processing controller, the amplifier's signal processing controller can be used to acquire and calculate the deceleration conditions of the EV from data acquired from the vehicle controller area network (CAN). Attached Figure Description

[0012] Figure 1 This is a diagram illustrating an electric vehicle (EV) to which embodiments of the present disclosure are applied.

[0013] Figure 2 This is a diagram illustrating an example of the flow of input and output values ​​in an embodiment of this disclosure.

[0014] Figure 3 It is a flowchart used to describe the algorithm from the input of various signals to the output of the sound output device.

[0015] Figure 4 The results show the indoor noise level and the EV deceleration mode tone control performed based on the full-load acceleration / deceleration conditions from 0kph to 100kph at the EV speed.

[0016] Figure 5 The results of tone control for EV deceleration mode are shown after full-load acceleration / acceleration conditions from 0 kph to 100 kph in the EV, based on regenerative braking operation.

[0017] Figure 6 The EV deceleration signal or regenerative braking signal is identified, and then a weight value is assigned to the EV deceleration signal or regenerative braking signal.

[0018] Figure 7 This is a flowchart used to describe the application of a computationally inefficient order tracking algorithm, where the Nth order component is extracted based on revolutions per minute (RPM) information.

[0019] Figure 8 This is a flowchart illustrating another example of an algorithm used to describe the process from the input of various signals to the output of a sound output device. Detailed Implementation

[0020] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. These embodiments are examples of the present disclosure and may be implemented in various different forms by those skilled in the art to which the present disclosure pertains, such that the present disclosure is not limited to these embodiments.

[0021] Figure 1 This is a diagram illustrating an electric vehicle (EV) to which embodiments of the present disclosure are applied, and Figure 2 This is a diagram illustrating an example of the flow of input and output values ​​in an embodiment of this disclosure.

[0022] Reference Figure 1 A vibration sensor 10 for measuring vibration signals generated when the motor rotates, a CAN signal 20 connected via a controller local area network (CAN) in the vehicle, a signal processing controller 30 for processing the vibration signal and the CAN signal 20, and a sound output device 40 are all installed in the EV to implement an embodiment of the present disclosure.

[0023] The vibration signal of the motor measured by the vibration sensor 10 is input to the signal processing controller 30, enabling the vibration characteristics to be measured in real time according to the rotation of the motor. The vibration sensor 10 may be a microelectromechanical system (MEMS) sensor, which includes a knock sensor method that can convert analog signals into digital signals through a digital signal conversion module, in which the digital signals themselves are processed.

[0024] The motor's revolutions per minute (RPM), accelerator pedal opening, and vehicle speed can be obtained from CAN signal 20. Information about drive mode changes, motor power, and vehicle driving characteristics can also be obtained.

[0025] The signal processing controller 30 can determine the driving conditions of the vehicle, whether it is accelerating, decelerating, or traveling at a constant speed, or it can determine the driver's intention based on the vibration signal and CAN signal 20 as input signals. It can also generate a target tone signal using the motor's RPM and vibration signal, and send the target tone signal as output data to the audio output device 40. A digital signal processor (DSP) can be applied to the vehicle's audio layer. A DSP can also be used for voice coding, which digitizes speech as an analog signal, and refers to an integrated circuit that allows mechanical devices to process digital signals quickly.

[0026] The sound output device 40 outputs the output data received from the signal processing controller 30 via a speaker, which is mounted in the engine compartment containing the motor to output a specific frequency band. To protect pedestrians, the sound output device 40 can be installed on the outside of the engine compartment instead of the inside, and the sound can be output to the driver or passengers via speakers installed inside the vehicle.

[0027] Figure 2 This diagram illustrates how the signal processing controller 30 acquires and calculates real-time information about the motor's RPM and vibration, as well as vehicle CAN information, from the vibration sensor 10, and then outputs acceleration or deceleration sounds to the interior of the vehicle via an external audio amplifier. As mentioned above, the location of the sound output device 40 can be either outside the vehicle or inside the engine compartment.

[0028] The vibration level caused by the rotation of the EV's motor is significantly lower than that caused by the combustion of an internal combustion engine. Therefore, it is important to select a sensor location where the sensor can accurately detect small changes in vibration level. The method for selecting the sensor location is as follows.

[0029] (1) First, a high-amplitude position is selected during frequency sweep by analyzing the structural analysis model of the EV's motor. Since the vibration sensor should be mounted on a flat surface, a position with high amplitude sensitivity should be selected based on the flatness of the surface. In addition, the vibration sensor measures vibration in the direction perpendicular to the seat surface. That is, the amplitude change in the vertical direction can be predicted relative to the seat surface through structural analysis.

[0030] (2) After structural analysis, the output torque of the motor under each load was measured, and the level change of each vibration order of the motor was simultaneously measured. Regression analysis was then performed based on the changes in the motor's output torque and the level change of the vibration order under the motor's load. Therefore, the motor's output characteristics and coefficient of determination R can be used. 2 A position is extracted with high sensitivity using an Nth-order component greater than 0.9, where the maximum amplitude is formed. That is, the position that best represents the amplitude characteristics caused by the motor's vibration can be selected as the final position.

[0031] In an electric vehicle (EV), the power performance of a motor is represented by its output torque. In embodiments of this disclosure, to perform tone control based on motor vibration, a component should be extracted from among a multitude of information related to the motor's vibration signal, based on the motor's RPM, and selected as the Nth-order component. This component is highly correlated with the motor's order-level characteristics and the trend of the output torque of a motor with these order characteristics. The order component varies depending on the motor's internal structure, including the number of magnetic cores.

[0032] Figure 3 This is a diagram used to describe the algorithm, which shows the calculation process from the input of various signals (S10) to the output (S43) of the sound output device 40.

[0033] The input signals can be measured, allowing the vibration sensor 10 to measure the vibration signal of the EV's motor. The EV's motor RPM, pedal opening, vehicle speed data, and regenerative braking settings can be input from the CAN signal 20. The signal processing controller 30 performs calculations using the algorithm described below, and calculates the final output in the sound output device 40, which includes the indoor and outdoor audio speakers.

[0034] The Nth order component is extracted from the input vibration signal of the motor, the Nth order component is set as the reference order component, and the level relative to the Nth order component (i.e. the level relative to the reference order component) is determined (S30).

[0035] First, a reference order component is calculated from the Nth order component. Then, this reference order component is input to the signal processing controller 30 so that the reference order component can always be used as the reference order component. Alternatively, it can be configured such that a new Nth order component is extracted from the vibration signal of the motor at specific time intervals, and the signal processing controller 30 automatically determines the Nth order component.

[0036] Simultaneously, order components (e.g., second, fourth, sixth, or twelfth order) can be generated relative to the RPM of the motor acquired in real time (S31).

[0037] When the Nth order component is determined to be the reference for the input of the order level in step S30, the order can be arranged by matching the Nth order component with the order component generated in S31, and the amplification level of the arranged order component can be determined to perform real-time amplification control (S40).

[0038] First, a variable band filter is applied to the RPM of the EV motor from the CAN signal 20 (S37). The variable band filter is a bandpass filter that removes frequency components with frequencies less than or equal to a predetermined frequency and frequency components with frequencies greater than or equal to a predetermined frequency from the input signal, so that the output components are only within a predetermined frequency band. The variable band filter can be formed by a combination of a low-pass filter and a high-pass filter. Therefore, in S40 or S41 following S37, the EV mode tone can be implemented only for the predetermined frequency band region.

[0039] Meanwhile, in order to reflect changes in vehicle dynamic performance in the EV's tone control and achieve a sound that corresponds to the driver's acceleration / deceleration intentions, a weight value can be assigned to the RPM (S32) of the EV's motor from the CAN signal 20.

[0040] The weight value can even be assigned to the opening measure of the accelerator pedal from the CAN signal 20 (S33), and the differential variance of the vehicle speed can be applied to the vehicle speed data from the CAN signal 20 (S34).

[0041] Acceleration conditions (S38) or deceleration conditions (S39) are determined based on a weighted value relative to the motor's RPM (S32), a weighted value for the accelerator pedal opening (S33), and the differential variance of the vehicle speed (S34). That is, acceleration conditions can be determined from one or more of the increase in vehicle speed, the increase in the motor's RPM, and the increase in the accelerator pedal opening; and deceleration conditions can be determined from one or more of the decrease in vehicle speed, the decrease in the motor's RPM, and the decrease in the accelerator pedal opening.

[0042] Alternatively, deceleration conditions can be determined based on vehicle speed data or regenerative braking information from CAN signal 20. When deceleration conditions are determined, vehicle speed weight values ​​can be assigned to vehicle speed data (S35), and deceleration conditions can be determined when regenerative braking is determined based on the regenerative braking setting value through real-time monitoring (S36).

[0043] When the current condition is determined to be an acceleration condition, EV acceleration mode tone control is performed in S40. The Nth order component extracted from the input vibration signal of the motor is set as the reference order component, and the Nth order component (i.e., the horizontal input relative to the reference order component (S30)) is matched with the order component generated in S31 to perform order arrangement (S40), thereby performing EV acceleration mode tone control.

[0044] Meanwhile, in the EV acceleration mode tone control, the RPM of the EV motor from the CAN signal 20 and the RPM of the EV motor after passing through the variable frequency band filter can be applied.

[0045] When the current condition is determined to be a deceleration condition, EV deceleration mode tone control is performed in S41. The Nth order component extracted from the input vibration signal of the motor is set as the reference order component, and the Nth order component (i.e., the horizontal input relative to the reference order component (S30)) is matched with the order component generated in S31 to perform order arrangement (S40), thereby performing EV deceleration mode tone control.

[0046] Meanwhile, in the EV deceleration mode tone control, the RPM of the EV motor from the CAN signal 20 and the RPM of the EV motor after passing through the variable frequency band filter can be applied.

[0047] By setting the order arrangement to be the same as that in EV acceleration mode, the tone control of electric vehicle deceleration mode is applied to tone control, and the reduction level of the arranged order components is determined, thereby enabling real-time control of the reduction level.

[0048] The output is the EV mode tone set by the EV acceleration / deceleration mode tone control (S43). The final output of the EV mode tone is performed in the sound output device 40, which includes indoor audio speakers and outdoor audio speakers. An acceleration sound is output in acceleration mode, and a deceleration sound is output in deceleration mode.

[0049] Figure 4The diagram shows the interior noise level and the results of EV deceleration mode tone control performed based on full-load acceleration / deceleration conditions from 0 kph to 100 kph at EV speed. That is, the results are the tone control in both acceleration and deceleration modes, and even in deceleration mode, the same tone as in acceleration mode provides a fade-out feel in the same way as the vehicle's control performance. e-ESEV means enhanced electronic sound in the EV.

[0050] When tone control is not applied in EV deceleration mode, a robust EV sound is provided during acceleration. However, during deceleration, no sound control is applied, and only high-frequency fine noise from the motor / reduction gears is detected, resulting in discomfort. Therefore, the same tone as in acceleration mode can be achieved through tone control in EV deceleration mode.

[0051] Figure 5 This diagram illustrates the results of sound control in EV deceleration mode based on regenerative braking operation following full-load acceleration / acceleration conditions from 0 kph to 100 kph at the EV's vehicle speed. EV regenerative braking is a mode used to charge the EV battery using braking force (reverse torque) during the inertial travel after acceleration. As the regenerative braking level increases, the braking force of the brakes is generated strongly under coasting conditions. Therefore, sound control is required, and the sound level controlled in EV deceleration mode for each level of regenerative braking condition is increased to enhance the deceleration sound level as the regenerative braking level increases from the first regenerative braking level.

[0052] Because the regenerative braking phase generates high and strong braking force, the time required for the regenerative braking phase is shorter during the acceleration of an EV from 0 kph to 100 kph and then back to 0 kph under full-load acceleration conditions.

[0053] exist Figure 3 In S39, after identifying the EV deceleration signal or regenerative braking signal, the deceleration conditions for the EV deceleration mode tone control are determined as follows. First, deceleration conditions during driving include gently pressing the accelerator pedal (e.g., the accelerator pedal opening changes from 50% to 0%), a decrease in the EV motor's RPM (e.g., a change from high RPM to low RPM), a decrease in vehicle speed (a change from high speed to low speed), and whether the brakes are operated (e.g., the brakes are operated during deceleration). Second, the regenerative braking condition is a condition that excludes only the brake operation from the deceleration conditions during driving, and includes gently pressing the accelerator pedal (e.g., the accelerator pedal opening changes from 50% to 0%), a decrease in the EV motor's RPM (e.g., a change from high RPM to low RPM), and a decrease in vehicle speed (a change from high speed to low speed), and the regenerative braking level can be set and monitored by the driver.

[0054] refer to Figure 6 The system identifies either the EV deceleration signal or the regenerative braking signal, and then assigns weight values ​​to either signal to enable fade-out triggering. Specifically, it assigns weight values ​​from 0 to 1 to each of the following: the accelerator pedal descent rate, the EV motor RPM descent rate, the vehicle speed descent rate, and the braking pedal force, in order to perform a fade-out operation that gradually reduces the sound level.

[0055] from Figure 6 As can be seen, when time counting is performed to allow weight values ​​to be applied in real time over time, the weight value of the sound level decreases over time during deceleration. This can be represented as a fade-out lookup table or mapping, and such a fade-out table or mapping is applied to make the final output decelerated sound. Meanwhile, Figure 6 The diagram shows the trend that the slope of the sound level weight value decreases over time due to the fade-out operation, meaning that the sound level weight value decreases rapidly and then gradually.

[0056] As mentioned above, in Figure 3 In this process, all processing from CAN data acquisition to tone control is performed in the signal processing controller 30. Meanwhile, in... Figure 7 In the process, vibration sensor 10 is used to measure the vibration signal of the EV motor and extract the Nth order component (S30). The EV acceleration mode tone control determined according to the acceleration condition and the EV deceleration mode tone control determined according to the deceleration condition can be executed in the vehicle signal processing controller. However, the acquisition and calculation of CAN data can be performed in the amplifier signal processing controller set in the amplifier.

[0057] In other words, the signal processing controller can be divided into: a vibration sensor signal processing controller 50, used to process the vibration signal measured by the vibration sensor 10; and an external amplifier signal processing controller 60, used to acquire and calculate CAN data. That is, the vibration sensor signal processing controller 50 can extract the Nth order component (S30) and determine the acceleration and deceleration conditions (S38 and S39) to perform EV mode tone control (S40 and S41).

[0058] Meanwhile, the external amplifier signal processing controller 60 can control all operations except for S30 and S38 to S41.

[0059] In other words, the microcontroller unit (MCU) of the external amplifier signal processing controller 60 can perform integrated EV tone control by receiving the EV tone control output signal and vehicle CAN data from the vibration sensor signal processing controller 50 in S30 and S38 to S41, and then output the result of the integrated EV tone control through various speakers. The function for providing the target tone output signal to the vibration sensor signal processing controller 50 is directly executed. Figure 3 The calculations in S30 and S38 to S41.

[0060] At the same time, by setting the order arrangement in EV acceleration mode to be equal to each other, Figure 3 The tone control in EV deceleration mode under deceleration conditions is applied to tone control, while... Figure 8 Another embodiment could be considered. That is, instead of the order arrangement used in the acceleration mode, the order can be rearranged and set during deceleration. For example... Figure 8 As shown in S42, when a deceleration condition is determined, a sequence is arranged and set to provide the driver with notification of deceleration so that it can be used for purposes different from the acceleration mode, such as notifying the driver of the deceleration state and outputting the sound generated during deceleration to the outside as a notification sound to protect pedestrians. In addition to notifying the driver, an external notification sound that matches the vehicle's braking performance is also implemented, thereby contributing to pedestrian safety (S44).

[0061] Embodiments of the present invention relate to a technique for controlling a tone of sound that matches the performance of an EV (electric vehicle) and is desired by consumers based on the characteristics of the motor, wherein the technique is capable of extracting the order components of motor vibrations that are highly correlated with the motor output characteristics of the EV in real time, achieving the desired sound of an internal combustion engine that matches the power performance characteristics of the EV, and using high-frequency characteristics to control an ultra-modern sound.

[0062] Furthermore, even during deceleration, the tone of the speaker can be enhanced or altered using control settings employing the Nth-order component, and a fade-out can be applied taking into account EV characteristics (silence), thus naturally providing a deceleration tone. Therefore, during deceleration, unpleasant high-frequency fine noises can be masked, and a sound consistent with braking performance can be provided.

[0063] Although this disclosure has been described with reference to the accompanying drawings, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of this disclosure, and that it is not limited to the exemplary embodiments disclosed herein. Therefore, it should be noted that such substitutions or modifications fall within the scope of the claims of this disclosure, and the scope of this disclosure should be interpreted based on the appended claims.

Claims

1. A method for controlling the tone of an electric vehicle (EV) based on motor vibration under deceleration or regenerative braking conditions, the method comprising: The order components are calculated from the vibration signal of the rotary motor of the EV; Extract the coefficients R with definiteness from the calculated order components. 2 The Nth order component, the determination coefficient R 2 This indicates a linear relationship with respect to the output torque of the motor and is greater than or equal to a predetermined value; The revolutions per minute (RPM) of the motor in the EV is converted into frequency, and the order frequency is calculated. The order components are arranged by applying the vibration signal amplitude of the Nth order component to the level of the order frequency to be output, and the EV mode tone is set. and During EV deceleration, deceleration conditions are determined, and then the amplitude of the vibration signal of the Nth order component is applied to the level control of the order frequency to set the EV mode tone.

2. The method of claim 1, further comprising: A vibration sensor is used to measure the vibration of the rotary motor of the EV.

3. The method of claim 1, further comprising: Sound is played through an audio speaker, the sound being based on the set EV mode tone.

4. The method of claim 1, further comprising: The output tone of the EV mode applies the deceleration intention.

5. The method of claim 4, wherein, The deceleration condition is determined by the driver's braking.

6. The method of claim 5, further comprising: After determining the deceleration conditions, a fade-out algorithm is used in the level control of the order frequency.

7. The method of claim 6, wherein, The fade-out algorithm uses a deceleration weight value, which is one or more of the following: the decrease in the RPM of the motor of the EV, the decrease in the opening of the accelerator pedal, the decrease in vehicle speed, and the increase in the braking force of the brake pedal.

8. The method of claim 7, further comprising: The deceleration weight value is applied and decreases over time.

9. The method according to claim 8, wherein, The slope of the deceleration weight value decreases over time.

10. The method according to claim 9, wherein, The deceleration weight value converges to a predetermined value over time.

11. The method according to claim 6, wherein, The fade-out algorithm uses the product of two or more selected deceleration weight values, which correspond to the decrease in the RPM of the motor of the EV, the decrease in the opening of the accelerator pedal, the decrease in vehicle speed, and the increase in the braking pedal force, respectively.

12. The method according to claim 11, wherein, The fade-out algorithm uses a lookup table that stores the deceleration weight values.

13. The method according to claim 4, further comprising: The order components are rearranged by applying the amplitude of the vibration signal of the Nth order component to the level of the order frequency to be output.

14. The method according to claim 13, wherein, The rearrangement of the order components includes using interior speakers to provide the driver with a deceleration notification sound.

15. The method according to claim 13, wherein, The rearrangement of the order components includes using outdoor loudspeakers to provide decelerating sounds to protect pedestrians.

16. A method for controlling the tone of an electric vehicle (EV) based on motor vibration under deceleration or regenerative braking conditions, the method comprising: The order components are calculated from the vibration signal of the rotary motor of the EV; Extract the coefficients R with definiteness from the calculated order components. 2 The Nth order component, the determination coefficient R 2 This indicates a linear relationship with respect to the output torque of the motor and is greater than or equal to a predetermined value; The revolutions per minute (RPM) of the motor in the EV is converted into frequency, and the order frequency is calculated. The order components are arranged by applying the vibration signal amplitude of the Nth order component to the level of the order frequency to be output, and the EV mode tone is set. and During the deceleration of the EV by regenerative braking, the amplitude of the vibration signal of the Nth order component is applied to the level control of the order frequency to set the EV mode tone.

17. The method according to claim 16, wherein, A fade-out algorithm is used in the level control of the order frequency, and the fade-out algorithm uses a deceleration weight value, which uses one or more of the following: the amount of reduction in the RPM of the motor of the EV, the amount of reduction in the opening of the accelerator pedal, the amount of reduction in vehicle speed, and the amount of increase in the braking pedal force.

18. A method for controlling the tone of an electric vehicle (EV) based on motor vibration under deceleration or regenerative braking conditions, the method comprising: The order components are calculated from the vibration signal of the rotary motor of the EV; extracting an Nth order component having a certain coefficient R 2 from among the calculated order components, the certain coefficient R 2 indicating a linear relationship with respect to an output torque of the motor and being greater than or equal to a predetermined value; The revolutions per minute (RPM) of the motor in the EV is converted into frequency, and the order frequency is calculated. The order components are arranged by applying the vibration signal amplitude of the Nth order component to the level of the order frequency to be output, and the EV mode tone is set. and During EV deceleration, deceleration conditions are determined, and then the same order arrangement as in EV acceleration mode is set to control the output of the order frequency for setting the EV mode tone.

19. The method according to claim 18, wherein, The deceleration condition is determined by driver braking or regenerative braking.

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