Control method and device for reducing noise, equipment, storage medium and product thereof

Abstract

The invention discloses a control method and device for reducing noise, equipment, a storage medium and a product thereof, and relates to the field of hybrid engine control, the method is applied to an extended-range vehicle model, and the disclosed method comprises the steps that before an engine enters a fixed-point power generation working condition, a breakpoint of an engine EGR control curve is selected, the EGR rate of the breakpoint is increased, and the engine EGR control curve is determined; the EGR rate of the engine EGR control curve at each moment is increased along with the increase of the EGR rate of the breakpoint, the EGR rate is subjected to ignition angle matching, and the engine is controlled to operate according to the matched ignition angle and EGR rate, so that the high-frequency combustion noise of the engine is reduced. Compared with the prior art that a sound insulation device is adopted for reducing the high-frequency combustion noise of the engine, the EGR rate of the engine is improved, slow matching is conducted on the ignition angle, and therefore the pressure rising rate in an engine cylinder and the cylinder pressure are reduced, the high-frequency combustion noise of the engine is reduced, and the vehicle cost is also reduced.

Description

Technical Field

[0001] The present application relates to the field of hybrid engine control technology, and in particular to a noise reduction control method, device, equipment, storage medium and product thereof. Background Art

[0002] Currently, all hybrid models are equipped with hybrid-specific engines, but when hybrid models, especially extended-range vehicles, use fixed-point power generation, the engine operating condition is in a stable condition. Currently, hybrid engines have the characteristics of large compression ratio and high combustion efficiency, which causes the engine to produce high-frequency combustion noise when in fixed-point power generation conditions. The engine combustion noise can be clearly felt in the vehicle cabin, which is not customer-friendly.

[0003] In current hybrid vehicles, the commonly used optimization solution is to use sound insulation devices, but sound insulation devices have problems with cost and the lack of space in the cabin. Summary of the invention

[0004] The main purpose of the present application is to provide a noise reduction control method, device, equipment, storage medium and its product, aiming to solve the technical problem of high-frequency combustion noise of hybrid dedicated engines.

[0005] To achieve the above object, the present application provides a control method for reducing noise, which is applied to a range-extended vehicle. The control method for reducing noise includes:

[0006] Before the engine enters the fixed-point power generation condition, the breakpoint of the engine EGR control curve is selected;

[0007] The EGR rate of the breakpoint is increased, and the EGR rate of the engine EGR control curve at each moment is increased as the EGR rate of the breakpoint is increased;

[0008] performing ignition angle matching on the EGR rate;

[0009] The engine operation is controlled according to the matched ignition angle and the EGR rate to reduce the high-frequency combustion noise of the engine.

[0010] Optionally, the step of selecting a breakpoint of the engine EGR control curve before the engine enters the fixed-point power generation condition specifically includes:

[0011] Before the engine enters the fixed-point power generation operating condition, a first operating point and a second operating point are selected in the engine EGR rate control curve;

[0012] Select a breakpoint between the first operating point and the second operating point.

[0013] Optionally, the step of increasing the EGR rate at the breakpoint specifically includes:

[0014] If the EGR rate increases between the first operating point and the second operating point, the EGR rate at the breakpoint is increased according to the EGR rate at the second operating point.

[0015] Optionally, after the step of increasing the EGR rate of the breakpoint, the method further comprises:

[0016] If the EGR rate is reduced between the first operating point and the second operating point, the EGR rate at each moment between the first operating point and the second operating point is linearly increased and controlled according to time.

[0017] Optionally, after the step of increasing the EGR rate of the breakpoint, the method further comprises:

[0018] If the engine air-fuel ratio is within the first fluctuation range, the breakpoint EGR rate is increased to the second operating point EGR rate;

[0019] If the engine air-fuel ratio is not within the first fluctuation range, the breakpoint EGR rate is increased to a preset multiple of the second operating point EGR rate.

[0020] Optionally, after the step of selecting a breakpoint between the first operating point and the second operating point, the method further includes:

[0021] If the engine is operating at a time corresponding to the second operating point, the EGR rate is stopped from being increased.

[0022] In addition, to achieve the above-mentioned purpose, the present application also proposes a control device for reducing noise, the device comprising:

[0023] The breakpoint module is used to select the breakpoint of the engine EGR control curve before the engine enters the fixed-point power generation condition;

[0024] An improving module, used for improving the EGR rate of the breakpoint, the EGR rate of the engine EGR control curve at each moment is improved as the EGR rate of the breakpoint is improved;

[0025] A matching module, used for performing ignition angle matching on the EGR rate;

[0026] The reduction module is used to control the engine operation according to the matched ignition angle and the EGR rate to reduce the high-frequency combustion noise of the engine.

[0027] In addition, to achieve the above-mentioned purpose, the present application also proposes a noise reduction control device, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the noise reduction control method.

[0028] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by the processor, the steps of the noise reduction control method are implemented.

[0029] In addition, to achieve the above-mentioned purpose, the present application also proposes a computer program product, which includes a computer program, and when the computer program is executed by a processor, the steps of the noise reduction control method are implemented.

[0030] One or more technical solutions proposed in this application have at least the following effects:

[0031] The present application selects the breakpoint of the engine EGR control curve before the engine enters the fixed-point power generation condition, increases the EGR rate at the breakpoint, and the EGR rate at each moment of the engine EGR control curve increases as the EGR rate at the breakpoint increases, matches the EGR rate with the ignition angle, and controls the engine operation according to the matched ignition angle and EGR rate to reduce the high-frequency combustion noise of the engine. Compared with the prior art that uses a sound insulation device to reduce the high-frequency combustion noise of the engine, by increasing the EGR rate of the engine and slowly matching the ignition angle, the pressure rise rate and cylinder pressure in the engine cylinder are reduced, the high-frequency combustion noise of the engine is reduced, and the vehicle cost is also reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0033] Figure 1 A schematic flow chart of a first embodiment of a noise reduction control method proposed in an embodiment of the present application;

[0034] Figure 2 A schematic flow chart of a second embodiment of a noise reduction control method proposed in an embodiment of the present application;

[0035] Figure 3 A schematic flow chart of a third embodiment of a noise reduction control method proposed in an embodiment of the present application;

[0036] Figure 4 A schematic flow chart of a fourth embodiment of a noise reduction control method according to an embodiment of the present application;

[0037] Figure 5 A schematic diagram of the module structure of a control device for reducing noise according to an embodiment of the present application;

[0038] Figure 6 This is the EGR control curve diagram of the vehicle engine in this application;

[0039] Figure 7 This is the vehicle engine ignition angle control curve diagram in this application.

[0040] Description of Figure Numbers:

[0041] Label name Label name 10 Breakpoint module 20 Lifting module 30 Matching module 40 Lower the module

[0042] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0043] It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0044] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0045] In addition, the descriptions of "first", "second", etc. in this application are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0046] The main solution of the embodiment of the present application is: by increasing the EGR rate of the engine and slowly matching the ignition angle, the pressure rise rate and cylinder pressure in the engine cylinder are reduced, thereby reducing the high-frequency combustion noise of the engine.

[0047] In this embodiment, for the convenience of description, the following description is made with the vehicle controller as the execution subject.

[0048] At present, hybrid models are all equipped with hybrid-specific engines. However, when hybrid models, especially extended-range vehicles, use fixed-point power generation, the engine is in a stable working condition. The current hybrid engine has the characteristics of large compression ratio and high combustion efficiency, which results in high high-frequency combustion noise of the engine during fixed-point power generation. The engine combustion noise can be clearly felt in the vehicle cabin, which is not friendly to customers. Hybrid-specific engines have the characteristics of large compression ratio and efficient combustion, high combustion pressure in the cylinder, and the pressure rise rate is relatively large compared to traditional vehicles. How to reduce the engine combustion noise based on NVH is a problem that this patent solution needs to solve.

[0049] The present application provides a solution, by selecting the breakpoint of the engine EGR control curve before the engine enters the fixed-point power generation condition, increasing the EGR rate at the breakpoint, the EGR rate at each moment of the engine EGR control curve increases as the EGR rate at the breakpoint increases, the EGR rate is matched with the ignition angle, and the engine operation is controlled according to the matched ignition angle and EGR rate to reduce the high-frequency combustion noise of the engine. Compared with the prior art that uses a sound insulation device to reduce the high-frequency combustion noise of the engine, by increasing the EGR rate of the engine and slowly matching the ignition angle, the pressure rise rate and cylinder pressure in the engine cylinder are reduced, the high-frequency combustion noise of the engine is reduced, and the vehicle cost is also reduced.

[0050] It should be noted that the NVH angle refers to the noise, vibration and harshness angle, which describes the noise, vibration and discomfort generated by the vehicle during driving. NVH performance is one of the important indicators for measuring the quality and comfort of a car. Hybrid engines do have the characteristic of a large compression ratio, which is designed to improve the thermal efficiency and fuel economy of the engine. The compression ratio refers to the ratio of the maximum volume to the minimum volume (i.e. the volume of the combustion chamber) in the engine cylinder. Hybrid engines usually have a higher compression ratio, generally between 15:1 and 16:1, or even higher. This high compression ratio design helps to make better use of fuel and improve combustion efficiency.

[0051] Based on this, an embodiment of the present application provides a control method for reducing noise.

[0052] Reference Figure 1 , Figure 1 This is a flow chart of the first embodiment of the noise reduction control method proposed in the embodiments of the present application.

[0053] Considering the high cost of the sound insulation device used in the prior art, in order to reduce the high-frequency combustion noise of the engine, such as Figure 1As shown, the method is applied to a range-extended vehicle, and the noise reduction control method includes steps S10 to S40:

[0054] Step S10: before the engine enters the fixed-point power generation condition, a breakpoint of the engine EGR control curve is selected.

[0055] It should be noted that the extended-range vehicle model is an extended-range electric vehicle, which is a plug-in series hybrid vehicle that is driven purely by electricity. Fixed-point power generation refers to the extended-range electric vehicle under specific operating conditions, through precise control of the power generation power of the range extender (usually an internal combustion engine with a generator) to meet the vehicle's demand for electricity and keep the engine running at an efficient and stable operating point, for example: the engine speed fluctuation range is Arpm±30rpm, and the torque fluctuation range is BNm±10Nm. The EGR rate is the exhaust gas recirculation rate, which refers to the percentage of exhaust gas entering the cylinder to the total intake volume. The EGR control curve is how the EGR rate is adjusted according to the operating status of the engine under different operating conditions to achieve the best balance between emissions and performance. Such as Figure 6 As shown, let the total time of the horizontal axis of the EGR control curve be t, the starting point and the ending point of the EGR control curve are point A and point B respectively, the breakpoint is point C, and the breakpoint can be selected at the (1 / 2)t time point for breakpoint control.

[0056] Step S20: increasing the EGR rate at the breakpoint, and the EGR rate at each moment of the engine EGR control curve increases as the EGR rate at the breakpoint increases.

[0057] It should be noted that if Figure 6 As shown, the EGR rate of the breakpoint is increased so that the EGR control curve is improved from the straight line AB to the curve ACB.

[0058] Step S30: performing ignition angle matching on the EGR rate.

[0059] It should be noted that if Figure 7 As shown, the ignition angle from point A to point B is linearly controlled according to the time axis, and the slope of the linear control can be set according to the actual situation, which is not limited in this embodiment. The (slow) matching of the ignition angle refers to the careful and gradual adjustment of the ignition advance angle during the engine matching calibration process to achieve the best power, economy and emission performance.

[0060] It is understandable that the ignition angle is the angle of the crankshaft from the ignition moment to the piston reaching the compression top dead center. The adjustment of the ignition angle will also affect the effect of the EGR rate on the engine performance. For example, when the ignition advance angle is less than the optimal value, the effective thermal efficiency decreases with the increase of the EGR rate; and when the ignition advance angle is greater than the optimal value, the effective thermal efficiency increases with the increase of the EGR rate.

[0061] Step S40: Controlling the engine operation according to the matched ignition angle and the EGR rate to reduce the high-frequency combustion noise of the engine.

[0062] It should be noted that increasing the EGR rate while slowly matching the ignition angle can reduce the pressure increase rate and cylinder pressure in the cylinder, thereby reducing the combustion noise in the cylinder.

[0063] It is understandable that a high EGR rate means a decrease in the amount of fresh air, which will worsen the combustion in the cylinder, resulting in a decrease in diesel engine economy and an increase in soot emissions. In addition, as the EGR rate increases, the ignition time is continuously delayed, the flame expansion rate slows down after ignition, the cylinder pressure and the maximum explosion pressure drop significantly, the time to reach the peak pressure is delayed, the heat release rate peak drops, and the heat release rate curve is pushed back as a whole.

[0064] In a specific implementation, before the engine enters the fixed-point power generation condition, a breakpoint of the engine EGR control curve is selected to increase the EGR rate of the breakpoint. The EGR rate at each moment of the engine EGR control curve increases as the EGR rate of the breakpoint increases. The EGR rate is matched with the ignition angle, and the engine operation is controlled according to the matched ignition angle and the EGR rate to reduce the high-frequency combustion noise of the engine, thereby reducing vehicle costs.

[0065] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the first embodiment can refer to the above introduction, and will not be repeated in the following. Figure 2 , Figure 2 This is a flow chart of a second embodiment of the noise reduction control method proposed in the embodiment of the present application.

[0066] Considering that the engine EGR rate can be increased by performing breakpoint control on the engine EGR control curve, such as Figure 2 As shown, the step S10 specifically includes:

[0067] Step S11: before the engine enters the fixed-point power generation condition, a first operating point and a second operating point are selected in the engine EGR rate control curve.

[0068] It should be noted that if Figure 6 As shown, the first operating point is point A, and the second operating point is point B.

[0069] Step S12: Select a breakpoint between the first operating point and the second operating point.

[0070] Step S121: If the engine is operating at a time corresponding to the second operating point, stop increasing the EGR rate.

[0071] It should be noted that the engine enters the fixed-point power generation operating condition after operating at the second operating point.

[0072] In a specific implementation, before the engine enters the fixed-point power generation condition, a first operating point and a second operating point are selected in the engine EGR rate control curve, and a breakpoint is selected between the first operating point and the second operating point. If the engine is operating at a moment corresponding to the second operating point, the EGR rate is stopped from being increased, thereby entering the fixed-point power generation condition.

[0073] Based on the second embodiment of the present application, in the third embodiment of the present application, the same or similar contents as those of the second embodiment can be referred to the above introduction, and will not be repeated in the following. Figure 3 , Figure 3 This is a flow chart of a third embodiment of the noise reduction control method proposed in the embodiments of the present application.

[0074] Considering the EGR rate control of the engine under different working conditions, such as Figure 3 As shown, the step S20 specifically includes:

[0075] Step S21: If the period between the first operating point and the second operating point is an EGR rate increasing period, the EGR rate at the breakpoint is increased according to the EGR rate at the second operating point.

[0076] It should be noted that if Figure 6 As shown, the EGR control curve of the EGR rate increasing condition is the curve ACB in the figure, and the EGR rate at the breakpoint can be greater than 90% of the EGR rate at the second operating point. For example, if the EGR rate at the second operating point is 20%, the EGR rate at the breakpoint is greater than 18%.

[0077] It should be noted that the impact of the EGR rate increase on engine performance includes: at low load, as the EGR rate increases, the combustion duration increases; but when the EGR rate reaches a certain value (such as 10%), the pumping loss and the combustion duration reach a balance. Under external characteristics, a small increase in the EGR rate (such as from 0 to 4%) can significantly suppress the knock trend (equivalent to suppressing the engine noise) and significantly advance the combustion center.

[0078] In a specific implementation, if the EGR rate increases between the first operating point and the second operating point, the EGR rate at the breakpoint is increased according to the EGR rate at the second operating point, thereby reducing the high-frequency combustion noise of the engine.

[0079] Furthermore, after step S21, the method further includes:

[0080] Step S211: If the period between the first operating point and the second operating point is an EGR rate reduction period, the EGR rate at each moment between the first operating point and the second operating point is linearly increased and controlled according to time.

[0081] It should be noted that if Figure 6 As shown, the EGR control curve of the EGR rate reduction condition is the straight line AB in the figure. The slope of the straight line AB can be set according to actual conditions and is not limited in this embodiment.

[0082] In a specific implementation, if the EGR rate is reduced between the first operating point and the second operating point, the EGR rate at each moment between the first operating point and the second operating point is linearly increased and controlled according to time, thereby reducing the high-frequency combustion noise of the engine.

[0083] Based on the third embodiment of the present application, in the fourth embodiment of the present application, the same or similar contents as those in the third embodiment can refer to the above introduction, and will not be repeated in the following. Figure 4 , Figure 4 This is a flow chart of a fourth embodiment of the noise reduction control method proposed in the embodiments of the present application.

[0084] Considering the setting of the breakpoint EGR rate, such as Figure 4 As shown, after step S20, the following further includes:

[0085] Step S201: If the engine air-fuel ratio is within the first fluctuation range, the breakpoint EGR rate is increased to the second operating point EGR rate.

[0086] It should be noted that the engine air-fuel ratio is the Lambda air-fuel ratio, which refers to a measurement and control parameter of the mixing ratio of air and fuel in the engine intake. The Lambda value is defined as the ratio of the actual air-fuel ratio to the theoretical air-fuel ratio. The theoretical air-fuel ratio refers to the ratio of the amount of air to the amount of fuel required for complete combustion of the fuel. For example, for gasoline, this ratio is approximately 14.7:1 (i.e., the mass ratio of air to gasoline is 14.7). When the Lambda value is equal to 1, it means that the actual air-fuel ratio is equal to the theoretical air-fuel ratio, and the engine combustion is most complete and efficient at this time. When the Lambda value is greater than 1, it means that the oxygen content is too much, that is, the amount of air is too much relative to the amount of fuel; when the Lambda value is less than 1, it means that the oxygen content is insufficient, that is, the amount of air is too little relative to the amount of fuel. In this embodiment, the first fluctuation range is that the Lambda air-fuel ratio is within 1±0.05, then the breakpoint (point C) EGR rate adaptive control is controlled with the maximum EGR rate (the second operating point (point B) EGR rate) as the target.

[0087] Step S202: If the engine air-fuel ratio is not within the first fluctuation range, the breakpoint EGR rate is increased to a preset multiple of the second operating point EGR rate.

[0088] It should be noted that the preset multiples can be 0.9, 0.95 and 1, and the breakpoint (point C) EGR rate can be adaptively controlled according to actual conditions.

[0089] In a specific implementation, if the engine air-fuel ratio is within the first fluctuation range, the breakpoint EGR rate is increased to the second operating point EGR rate; if the engine air-fuel ratio is not within the first fluctuation range, the breakpoint EGR rate is increased to a preset multiple of the second operating point EGR rate, thereby reducing the high-frequency combustion noise of the engine.

[0090] This application also provides a control device for reducing noise, please refer to Figure 6 , Figure 6 This is a schematic diagram of the module structure of the control device for reducing noise according to an embodiment of the present application, and the device includes:

[0091] The breakpoint module 10 is used to select the breakpoint of the engine EGR control curve before the engine enters the fixed-point power generation condition;

[0092] An improving module 20, used for improving the EGR rate of the breakpoint, the EGR rate of the engine EGR control curve at each moment is improved as the EGR rate of the breakpoint is improved;

[0093] A matching module 30, used for performing ignition angle matching on the EGR rate;

[0094] The reduction module 40 is used to control the engine operation according to the matched ignition angle and the EGR rate to reduce the high-frequency combustion noise of the engine.

[0095] In addition, to achieve the above-mentioned purpose, the present application also proposes a noise reduction control device, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the noise reduction control method.

[0096] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by the processor, the steps of the noise reduction control method are implemented.

[0097] In addition, to achieve the above-mentioned purpose, the present application also proposes a computer program product, which includes a computer program, and when the computer program is executed by a processor, the steps of the noise reduction control method are implemented.

[0098] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A control method for reducing noise, characterized in that: The method is applied to a range-extended vehicle, and the noise reduction control method includes: Before the engine enters the fixed-point power generation condition, the breakpoint of the engine EGR control curve is selected; The EGR rate of the breakpoint is increased, and the EGR rate of the engine EGR control curve at each moment is increased as the EGR rate of the breakpoint is increased; performing ignition angle matching on the EGR rate; The engine operation is controlled according to the matched ignition angle and the EGR rate to reduce the high-frequency combustion noise of the engine.

2. The noise reduction control method according to claim 1, characterized in that: The step of selecting the breakpoint of the engine EGR control curve before the engine enters the fixed-point power generation condition specifically includes: Before the engine enters the fixed-point power generation operating condition, a first operating point and a second operating point are selected in the engine EGR rate control curve; Select a breakpoint between the first operating point and the second operating point.

3. The noise reduction control method according to claim 2, characterized in that: The step of increasing the EGR rate at the breakpoint specifically includes: If the EGR rate increases between the first operating point and the second operating point, the EGR rate at the breakpoint is increased according to the EGR rate at the second operating point.

4. The noise reduction control method according to claim 3, characterized in that: After the step of increasing the EGR rate at the breakpoint according to the EGR rate at the second operating point if the period between the first operating point and the second operating point is an EGR rate increase operating condition, the method further includes: If the EGR rate is reduced between the first operating point and the second operating point, the EGR rate at each moment between the first operating point and the second operating point is linearly increased and controlled according to time.

5. The noise reduction control method according to claim 3, characterized in that: After the step of increasing the EGR rate at the breakpoint, the method further includes: If the engine air-fuel ratio is within the first fluctuation range, the breakpoint EGR rate is increased to the second operating point EGR rate; If the engine air-fuel ratio is not within the first fluctuation range, the breakpoint EGR rate is increased to a preset multiple of the second operating point EGR rate.

6. The noise reduction control method according to claim 2, characterized in that: After the step of selecting a breakpoint between the first operating point and the second operating point, the method further includes: If the engine is operating at a time corresponding to the second operating point, the EGR rate is stopped from being increased.

7. A noise reduction control device, characterized in that: The device comprises: The breakpoint module is used to select the breakpoint of the engine EGR control curve before the engine enters the fixed-point power generation condition; An improving module, used for improving the EGR rate of the breakpoint, the EGR rate of the engine EGR control curve at each moment is improved as the EGR rate of the breakpoint is improved; A matching module, used for performing ignition angle matching on the EGR rate; The reduction module is used to control the engine operation according to the matched ignition angle and the EGR rate to reduce the high-frequency combustion noise of the engine.

8. A noise reduction control device, characterized in that: The device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the noise reduction control method according to any one of claims 1 to 6.

9. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the noise reduction control method according to any one of claims 1 to 6 are implemented.

10. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the steps of the noise reduction control method according to any one of claims 1 to 6 are implemented.

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