DE102019121664A1 - Method and system for reducing noise in a motor vehicle - Google Patents

Abstract

The invention relates to a method for reducing disruptive background noises in a motor vehicle (10) with a drive motor (20), an interior and a multimedia system (70) that has at least one microphone (70), at least one audio unit (100) with a Processor (105) and a memory unit (107), comprising at least one amplifier (95) and at least one loudspeaker (90), with the following method steps: - Detection (S10) of background noises in the interior of the motor vehicle as input signals by the microphone (80) of the multimedia system (70); - Forwarding (S20) of the input signals of the microphone (80) to the audio unit (100); - Analysis (S30) of the frequency and amplitude spectrum of the background noise by means of a first algorithm of a software application of the processor (105) of the audio unit (100); - Calculating (S40) a compensation sound for reducing the background noise with the first algorithm and / or a further algorithm from the Pr processor (105) of the audio unit (100) based on the analyzed frequency and amplitude spectrum of the background noise; - outputting (S50) the compensation sound via the amplifier (95) and the loudspeaker (90) of the multimedia system (70).

Description

The present invention generally relates to a method and system for reducing noise in a motor vehicle with a drive engine.

It is known that instead of vehicles that are driven by an internal combustion engine, hybrid vehicles that are driven, for example, by an internal combustion engine and an electric motor, or electric vehicles that are driven by an electric motor that is powered by an energy storage system such as a battery or a fuel cell for example, hydrogen gas is fed as an energy source. Electric vehicles in particular are becoming increasingly popular with customers.

Modern vehicles also incorporate various noise reduction features that reduce the amount of noise generated by engines and powertrains during vehicle start-up and vehicle gear changes. For example, improvements in engine torque shaping, intake system designs, exhaust system designs, and powertrain mounts have reduced engine and drive noise. In addition, modern vehicle cabins contain sound-absorbing features such as upholstery, which further reduce the amount of engine and drive noise. In addition, electric vehicles and hybrid electric vehicles are only driven by an electric motor, at least at certain times, and therefore hardly generate any noise when the vehicle is started or when changing gears.

To quickly charge the energy storage system of electric vehicles, large electrical outputs with high DC voltages and currents are required. However, high electrical currents lead to excessive heating of the components and in particular of the battery cells, battery cell connectors and busbars. Therefore, the heat generated must be dissipated for safe operation of the energy storage system. To cool the individual components, fans are used on the external heat exchangers (cooler module). In addition, a refrigerant circuit with a refrigerant compressor is often used, but this generates a high level of noise. If the passengers decide to remain in the interior of the vehicle while the energy storage system is charging, these noise noises are perceived as unpleasant and annoying.

From the DE 10 2017 207543 A1 a method and system for reducing a sound pressure wave is known. A motor vehicle comprises a vehicle interior in which a sound receiver is positioned in such a way that it detects an input pressure wave in the vehicle interior and generates an input signal. In the vehicle, a fan with an adjustable angle of incidence of the blades of the fan wheel is positioned so that the fan can be heard inside the interior. A processor receives an input signal and determines its input frequency and phase. The angle of attack of the fan blade is now set in such a way that a compensation pressure wave with a compensation frequency which roughly corresponds to the input frequency and a compensation phase that is phase-shifted by about 180 ° with the input phase is generated.

The DE 10 2017 107538 A1 describes a control device and a control method for noise reduction for a vehicle, in particular for an electric vehicle or hybrid vehicle. The control device comprises a mounted auxiliary unit for the vehicle, such as an air conditioning system with an air conditioning compressor, the auxiliary unit emitting vibrations during operation, and a vibration sensor for detecting vibrations. In order to reduce the vibrations, controllable vibration actuators are used to generate counter-vibrations that dampen the vibrations of the auxiliary unit.

From the EP 2378133 B1 a fan unit and a method for controlling noises generated by an air conditioner are known. The system comprises a microphone for sound measurements of the air conditioning system and a processor for determining a damping signal which at least partially cancels out the measured sound and is output via a loudspeaker. The resulting sound is measured by means of a microphone and is used by the processor to modify the damping signal until an optimal result is achieved.

JPH 05232973 A describes a channel structure for a housing body which is suitable for active noise elimination. The channel has a curved shape so that noises can be transmitted to the inner wall surface of the case body of an electronic device or the like.

It is therefore the object of the present invention to reduce the noise pollution in the interior of a motor vehicle, in particular during the charging process of electric vehicles or hybrid vehicles with an energy storage system.

According to a first aspect, the invention provides a method for reducing disruptive background noises in a motor vehicle with a drive motor, an interior and a multimedia system ready. The multimedia system comprises at least one microphone, at least one audio unit with a processor and a memory unit, at least one amplifier and at least one loudspeaker. The method comprises the detection of background noises in the interior of the motor vehicle as input signals through the microphone of the multimedia system, the transmission of the input signals of the microphone to the audio unit, the analysis of the frequency and amplitude spectrum of the background noises using a first algorithm of a software application of the processor of the audio unit, which Calculating a compensation sound to reduce the background noise with the first algorithm and / or a further algorithm from the processor of the audio unit based on the analyzed frequency and amplitude spectrum of the background noise, and outputting the compensation sound via the amplifier and the loudspeaker of the multimedia system.

By generating the compensation sound, anti-noise is emitted in the interior of the motor vehicle, which reduces or eliminates the noises that occur, for example, when the energy storage system of an electric vehicle is charging, so that the background noise is reduced.

In an advantageous further development it is provided that the input signal of the microphone includes background noises and other audio noises such as speech inputs and the algorithm of the processor distinguishes the two types of noise and only calculates the compensation sound for the background noises.

In a further embodiment of the invention, the motor vehicle is designed as an electric vehicle or as a hybrid vehicle with an electric motor and comprises an energy storage system, the energy storage system being cooled with a coolant circuit and / or at least one fan.

In a further embodiment of the invention, the secondary noises are generated by a coolant compressor for the energy storage system and / or by a fan and / or by an air conditioning system and / or the secondary noises include the rolling noise of the wheels and / or the drive motor when the motor vehicle is in motion.

At least one algorithm of the software application of the processor is advantageously designed as a neural network, which is trained in a training phase with selected background noises of a basic motor vehicle.

In an advantageous further development, the trained neural network is used in the audio unit (deployment phase) and adapts to the specific parameters of the respective individual motor vehicle.

In a further embodiment of the invention, it is provided that the analyzed frequency and amplitude spectrum of the background noise is stored in whole or in part on a storage unit of the audio unit.

According to a second aspect, the invention provides a multimedia system for reducing disruptive background noises in a motor vehicle with a drive motor and an interior space. The multimedia system comprises at least one microphone, at least one audio unit with a processor and a memory unit, at least one amplifier and at least one loudspeaker. The microphone is designed to capture background noises in the interior of the motor vehicle as input signals and to pass these input signals on to the audio unit. The processor of the audio unit is designed to analyze the frequency and amplitude spectrum of the background noise using a first algorithm of a software application and to add a compensation sound to reduce the background noise with the first algorithm and / or another algorithm based on the analyzed frequency and amplitude spectrum of the background noise to calculate. The amplifier and the loudspeaker are designed to output the compensation sound.

In an advantageous further development of the invention it is provided that the input signal of the microphone includes background noises and other audio noises such as speech inputs and the algorithm of the processor is designed to distinguish the two types of noise and only calculate the compensation sound for the background noises.

In an advantageous embodiment, it is provided that the motor vehicle is designed as an electric vehicle or as a hybrid vehicle with an electric motor that includes an energy storage system, with a coolant circuit and / or at least one fan being provided to cool the energy storage system.

In a further embodiment, the background noises are generated by a coolant compressor for the energy storage system and / or by a fan and / or by an air conditioning system and / or the background noises include the rolling noise of the wheels and / or the drive motor when the motor vehicle is in motion.

At least one algorithm of the software application of the processor is advantageously designed as a neural network which can be trained in a training phase with selected background noises of a basic motor vehicle.

In an advantageous further development, the trained neural network can be used in the audio unit (deployment phase) and can be adapted to the specific parameters of the respective individual motor vehicle.

In a further embodiment, the audio unit comprises a storage unit on which the frequency and amplitude spectrum of the background noise can be stored.

According to a third aspect, the invention provides a motor vehicle with a drive motor and an interior space, the motor vehicle comprising a multimedia system according to the second aspect.

According to a fourth aspect, the invention provides a computer program product comprising an executable program code which is configured such that, when it is executed, it carries out the method according to the first aspect.

• 1 zeigt eine Übersichtsdarstellung zur Erläuterung einer Ausführungsform eines Kraftfahrzeugs gemäß dem dritten Aspekt der vorliegenden Erfindung;
• 2 zeigt ein schematisches Flussdiagramm, das eine Ausführungsform eines Verfahrens gemäß dem ersten Aspekt der vorliegenden Erfindung darstellt;
• 3 zeigt schematisch ein Computerprogrammprodukt gemäß einer

Further features, aspects and advantages of the invention or its embodiments are explained in the detailed description in connection with the following figures:

• 1 shows an overview diagram for explaining an embodiment of a motor vehicle according to the third aspect of the present invention;
• 2 Figure 12 is a schematic flow diagram illustrating an embodiment of a method according to the first aspect of the present invention;
• 3 shows schematically a computer program product according to one

Embodiment of the fourth aspect of the invention.

In the following description, for purposes of illustration and not limitation, specific details are set forth in order to facilitate a thorough understanding of the present invention. It will be apparent to those skilled in the art that the present invention can be carried out in other implementations deviating from these specific details.

In 1 is schematically a motor vehicle 10 shown. The vehicle 10 has a vehicle interior, not shown here, which includes seats, a steering wheel, a dashboard, windows and doors and other components. The vehicle 10 is for example an electric vehicle or a hybrid vehicle with a drive motor 20th , which is preferably designed as an electric motor. An energy storage system is used to supply energy to the electric motor 30th provided, which preferably has battery cells and cooling units with a coolant circuit. The refrigerant is preferably used with a refrigerant compressor 40 compressed to cool the battery cells. Furthermore, one or more fans can be used 50 be present as well as other ancillary units and vehicle components.

The car 10 also has a multimedia system 70 for the recording and playback of acoustic and optical signals, preferably in the dashboard of the motor vehicle 10 is arranged. But it is also conceivable that individual components of the multimedia system 70 at other positions in the vehicle 10 such as the steering wheel or on or in the vehicle seats. The multimedia system 70 includes one or more microphones 80 , one or more speakers 90 , preferably in the interior of the motor vehicle 10 are arranged, and an audio unit 100 with a processor 105 and a storage unit 107 as well as other modules and components, if applicable.

In connection with the invention, a “processor” can be understood to mean, for example, a machine or an electronic circuit. A processor can in particular be a main processor (Central Processing Unit, CPU), a microprocessor or a microcontroller, for example an application-specific integrated circuit or a digital signal processor, possibly in combination with a memory unit for storing program commands, etc. . A processor can also be understood to be a virtualized processor, a virtual machine or a soft CPU. For example, it can also be a programmable processor that is equipped with configuration steps for executing the above-mentioned method according to the invention or is configured with configuration steps in such a way that the programmable processor uses the inventive features of the method, the component, the modules, or other aspects and / or implemented partial aspects of the invention.

In connection with the invention, a “memory unit” or “memory module” and the like can mean, for example, a volatile memory in the form of a random access memory (RAM) or a permanent memory such as a hard disk or a data carrier or z. B. can be understood as a removable memory module.

In connection with the invention, a “module” can be understood to mean, for example, a processor and / or a memory unit for storing program commands. For example, the processor is specially set up to execute the program instructions in such a way that the processor executes functions in order to implement or realize the method according to the invention or a step of the method according to the invention.

Especially when fast charging the energy storage system 30th noises are generated especially by the refrigerant compressor 40 and the fan 50 generated. The charging process usually takes place when the vehicle is stationary. Such noises have a characteristic frequency and amplitude spectrum and are perceived by occupants of the motor vehicle as humming noises and are perceived as unpleasant. These humming noises are used as input signals from the microphone 80 recorded and to the audio unit 100 forwarded. But there can also be other background noises such as engine, tire and road noises or the noises of an air conditioning system in the motor vehicle 10 from the microphone 80 be included. The microphone 80 is preferably switched on permanently and can therefore all noises in the interior of the motor vehicle 10 record, tape.

The input signals from the microphone 80 are preferably in the storage unit 107 stored, either permanently or only temporarily. The processor 105 the audio unit 105 uses an algorithm in a software application to analyze the frequency spectrum and the amplitudes of the noise signal, which can consist of sound frequencies that are audible and inaudible to the human ear. The processor distinguishes here 105 the unwanted background noise from other desired noises for which the multimedia system 70 is designed and designed, such as the voice inputs of the driver or another occupant, for example when making phone calls or for voice control of individual components of the motor vehicle such as the navigation system, or the music playback of a piece of music. As the microphone 80 is used for recording voice control commands or telephone calls, this differentiation of the type of noise is essential for the method according to the invention. It can also be provided that in addition to the two types of noise - disruptive background noise and desired audio noise - there are also further categories of noises, each of which is produced by the processor 105 differentiated and assigned according to the respective category. It is therefore not an additional microphone 80 required for the analysis of the background noise, but due to the algorithm used, the microphone can 80 of the multimedia system 100 can also be used for recording background noise.

After analyzing the noise spectrum of the background noise, the processor now calculates 105 a compensation sound that is sent to an amplifier 95 passed and through the speaker 90 is issued. The artificially generated compensation sound has a frequency spectrum with corresponding amplitudes and phases displaced with respect to the input signal, so that in the spatial sound wave field in the interior of the motor vehicle 10 destructive interference occurs for the background noise and these are reduced. The compensation sound thus acts as compensation sound or anti-sound and the vehicle occupants in the vehicle cabin are less disturbed by the background noise, so that they have a quiet driving experience and / or, for example, their activities such as making a phone call using the multimedia system 100 can perform better, as they are not distracted by annoying background noises. Especially when charging the energy storage system 30th In the case of an electric vehicle, the driver and / or the occupants of the vehicle are staying 10 much more pleasant and the time spent waiting for the charging process to finish can also be used for work activities that require greater concentration. This represents a significant improvement, especially for people who are often on the road for work and who also use their vehicle as an extended office.

In a further development of the invention it can also be provided to use an artificial neural network as an algorithm for the analysis of the background noises and the generation of a compensation sound, which is based on parameters such as the charging speed of the energy storage system, the cooling performance of the cooling unit and coolant compressor and / or the time the charging process and / or the vehicle speed is trained (training phase). This trained neural network can then be used in the audio unit 100 is used (deployment phase) and adapts to the specific parameters of the respective individual motor vehicle 10 at. This reduces the computational effort by the processor 105 significantly reduced and thus a quick detection and analysis of the background noise takes place, whereby an efficient and effective generation of the compensation sound is made possible.

The analyzed frequency spectrum and / or the generated compensation sound is preferably stored in whole or in part, temporarily or permanently, on the storage unit 107 the audio unit 100 stored in order to use them, for example, for comparative analyzes and / or as a library.

No additional microphones are used for the procedure 80 or speakers 90 in the interior of the motor vehicle 10 needed, but the existing processor 105 of the multimedia system 20th can be expanded with the corresponding software functionalities. This also makes it possible to retrofit vehicles that are already in operation 10 enables.

The method according to the invention of noise reduction of undesired background noises can be used both when the vehicle is stationary and while driving, in order to compensate for rolling and road noises or other undesirable background noises. Since electric mobility in particular is associated with the expectation of low background noise, this impression can be reinforced. In principle, however, the method according to the invention can also be used for motor vehicles with an internal combustion engine.

In 2 the processing steps of the method according to the present invention are shown.

In a step S10, background noises in the interior of a motor vehicle are used as input signals through the microphone 80 of the multimedia system 70 detected.

In a step S20, the input signals of the microphone 80 to the audio unit 100 passed on.

In a step S30 the processor analyzes 105 the audio unit 100 the frequency and amplitude spectrum of the background noise using a first algorithm.

In a step S40 the processor calculates 105 the audio unit 100 a compensation sound for reducing the background noise with the first algorithm and / or a further algorithm based on the analyzed frequency and amplitude spectrum of the background noise.

In a step S50, the compensation sound is transmitted through the amplifier 95 and the speaker 90 of the multimedia system 100 issued.

3 schematically illustrates a computer program product 200 represents an executable program code 250 that is configured to carry out the method according to the first aspect of the present invention when carried out.

The present invention enables a motor vehicle 10 , which is preferably equipped with an electric motor, a noise reduction of disturbing background noises in the interior of the motor vehicle 10 by generating a compensation sound that acts as an anti-noise. The method can be used, for example, when rapidly charging the energy storage system 30th of an electric vehicle, but can also be used while driving in order to reduce the rolling noise of the tires, which is dominant at high speeds, as well as the hum of the electric motor due to anti-noise in an electric vehicle. This can increase the acoustic advantages of an electric vehicle for the occupants.

List of reference symbols

10

Motor vehicle

20th

engine

30th

Energy storage system

40

Refrigerant compressor

50

Fan

70

Multimedia system

80

microphone

90

speaker

95

amplifier

100

Audio unit

105

processor

107

Storage unit

200

Com puter program m product

250

Program code

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102017207543 A1 [0005]
• DE 102017107538 A1 [0006]
• EP 2378133 B1 [0007]

Claims (15)

A method for reducing annoying background noises in a motor vehicle (10) with a drive motor (20), an interior and a multimedia system (70), the at least one microphone (70), at least one audio unit (100) with a processor (105) and a Storage unit (107), comprising at least one amplifier (95) and at least one loudspeaker (90), with the following method steps: - Detection (S10) of background noises in the interior of the motor vehicle as input signals by the microphone (80) of the multimedia system (70); - forwarding (S20) the input signals of the microphone (80) to the audio unit (100); - Analyzing (S30) the frequency and amplitude spectrum of the background noise by means of a first algorithm of a software application of the processor (105) of the audio unit (100); - Calculating (S40) a compensation sound for reducing the background noise with the first algorithm and / or a further algorithm by the processor (105) of the audio unit (100) based on the analyzed frequency and amplitude spectrum of the background noise; - Output (S50) of the compensation sound via the amplifier (95) and the loudspeaker (90) of the multimedia system (70). Procedure according to Claim 1 , wherein the input signal of the microphone (80) comprises background noises and other audio noises such as speech inputs and the algorithm of the processor (105) distinguishes the two types of noise and calculates the compensation sound only for the background noises. Procedure according to Claim 1 or 2 , wherein the motor vehicle (10) is designed as an electric vehicle or as a hybrid vehicle with an electric motor (20) and comprises an energy storage system (30), the energy storage system (30) being cooled with a coolant circuit and / or at least one fan (50). Method according to one or more of the Claims 1 - 3 , the background noise being generated by a coolant compressor (40) for the energy storage system (30) and / or by a fan (50) and / or by an air conditioning system and / or the rolling noise of the wheels and / or the drive motor (30) during driving of the motor vehicle (10). Method according to one of the Claims 1 to 4th , wherein the at least one algorithm of the software application of the processor (105) is designed as a neural network that is trained in a training phase with selected background noises of a basic motor vehicle. Procedure according to Claim 5 , the trained neural network being used in the audio unit (100) (deployment phase) and adapting to the specific parameters of the respective individual motor vehicle (10). Method according to one or more of the Claims 1 - 6th , the analyzed frequency and amplitude spectrum of the background noise being wholly or partially stored on the storage unit (107) of the audio unit (100). A multimedia system (70) for reducing disruptive background noises in a motor vehicle (10) with a drive motor (20) and an interior, the multimedia system (70) having at least one microphone (80), at least one audio unit (100) with a processor (105) ) and a memory unit (107), at least one amplifier (95) and at least one loudspeaker (90), the microphone (80) being designed to detect background noises in the interior of the motor vehicle (10) as input signals and to send these input signals to the audio unit (100), the processor (105) of the audio unit (100) being designed to analyze the frequency and amplitude spectrum of the background noises using a first algorithm of a software application and a compensation sound to reduce the background noises using the first algorithm and / or a further one Calculate an algorithm based on the analyzed frequency and amplitude spectrum of the background noise, w whether the amplifier (95) and the loudspeaker (90) are designed to output the compensation sound. Multimedia system (70) Claim 8 , wherein the input signal of the microphone (80) comprises background noises and other audio noises such as speech inputs and the algorithm of the processor (105) is designed to distinguish the two types of noise and only calculate the compensation sound for the background noises. Multimedia system (70) Claim 8 or 9 , wherein the motor vehicle (10) is designed as an electric vehicle or as a hybrid vehicle with an electric motor (20) and comprises an energy storage system (30), a coolant circuit and / or at least one fan (50) being provided to supply the energy storage system (30) cool. Multimedia system (70) according to one or more of the Claims 8 - 10 , the background noises being generated by a coolant compressor (40) for the energy storage system (30) and / or by a fan (50) and / or by an air conditioning system and / or include the rolling noise of the wheels and / or the drive motor (30) when the motor vehicle (10) is in motion. Multimedia system (70) according to one of the Claims 8 to 11 , wherein the at least one algorithm of the software application of the processor (105) is designed as a neural network that can be trained in a training phase with selected background noises of a basic motor vehicle. Multimedia system (70) Claim 12 , wherein the trained neural network can be used in the audio unit (100) (deployment phase) and is designed to adapt to the specific parameters of the respective individual motor vehicle (10). A motor vehicle (10) with a drive engine and an interior, the motor vehicle (10) having a multimedia system (70) according to one or more of the Claims 8 to 13 includes. A computer program product (200) comprising an executable program code (250) which is configured such that, when it is executed, it executes the method according to one of the Claims 1 to 7th executes.

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