Noise reduction design methods, processors and storage media for rail transit vehicle traction systems

Abstract

This invention relates to a noise reduction design method, processor, and storage medium for a rail transit vehicle traction system. The method includes: designing top-level parameters based on the train's top-level performance requirements; establishing a relationship model between the weight and noise of the traction system equipment based on the top-level parameters, performing a weighted analysis of lightweighting and noise factors, and adjusting the top-level design parameters to minimize the evaluation results; simulating the actual operating state of the traction system based on the adjusted top-level design parameters, combined with the traction system's operating line conditions, maximum operating ambient temperature, and altitude, and calculating the current curve; calculating the equipment operating loss curve based on the current curve and the traction system's operating characteristics, designing cooling system parameters, and selecting cooling components based on the cooling system parameters. Through this method, unnecessary performance redundancy in the traction system can be reduced, equipment weight can be lowered, thereby improving the lightweight performance of the traction system and significantly improving the environmental friendliness and ride comfort of rail transit vehicles.

Description

Technical Field

[0001] This invention relates to the fields of rail transit vehicles and rail transit electrical equipment, specifically to a noise reduction design method, processor, and storage medium for a rail transit vehicle traction system. Background Technology

[0002] In recent years, with the rapid development of my country's rail transit industry and social economy, while rail transit vehicles provide people with high-speed and convenient travel services, they have also brought noise problems to the urban environment. The environmental problems faced by rail transit vehicles are becoming increasingly serious.

[0003] For rail transit vehicles, with the continuous increase in operating speed and the socio-economic development around the lines, the noise generated by the vehicles during operation has gradually received widespread attention in the industry. According to domestic and international research and testing on railway noise theory, rail transit vehicle noise mainly consists of traction noise, wheel-rail noise, and aerodynamic noise. When rail transit vehicles operate at low to medium speeds, the noise generated by the traction system is the primary source of vehicle noise. Therefore, specialized noise reduction design for the traction system and the development of low-noise traction systems are of great significance to the environmental friendliness and passenger comfort of rail transit vehicles.

[0004] The main components of a traction system include a traction motor, a traction transformer, and a traction converter. These components continuously generate noise during operation, which can be categorized into aerodynamic noise and electromagnetic noise based on their generation mechanisms.

[0005] 1) Aerodynamic noise refers to the noise generated by the airflow caused by the cooling fan of the traction system during its operation. Aerodynamic noise increases with the speed of the cooling fan.

[0006] 2) Electromagnetic noise refers to the noise generated by the alternating magnetic field on the traction system equipment during the power conversion process. It is mainly caused by the switching of power electronic devices during the power conversion process of the traction system.

[0007] Traditional noise control methods for rail transit vehicles mostly focus on increasing sound insulation equipment on tracks and vehicles, while research on noise reduction of the traction system itself is relatively limited. Most solutions rely on passive sound insulation and absorption to reduce noise. However, these methods typically cannot effectively reduce the noise generated by the traction system at its source. Summary of the Invention

[0008] This invention provides a noise reduction design method, processor, and storage medium for rail transit vehicle traction systems. Its purpose is to solve the problems of aerodynamic and electromagnetic noise generated during the operation of rail transit vehicle traction systems, and to reduce noise from the design source to improve environmental friendliness and passenger comfort.

[0009] To achieve the above objectives, the first aspect of the present invention provides a noise reduction design method for a traction system of a rail transit vehicle, comprising the following steps:

[0010] Based on the train performance requirements, the top-level parameters of the traction system are designed; the top-level parameters include: the maximum wheel circumference traction force of the whole vehicle, the inflection point of the traction force of the whole vehicle, the maximum electric braking force of the whole vehicle, the inflection point of the electric braking force of the whole vehicle, the number of train motors, and the gear transmission ratio.

[0011] Based on the top-level parameters, a model relating the weight and noise of the traction system equipment is established. Weighted analysis of lightweighting and noise factors is performed, and the top-level design parameters are adjusted to minimize the evaluation results.

[0012] Based on the adjusted top-level design parameters, combined with the traction system's operating line conditions, maximum operating ambient temperature, and altitude, the actual operating state of the traction system is simulated, and the current curve of the traction system during operation is calculated.

[0013] Based on the obtained current curve and the working characteristics of the traction system, the working loss curve of the equipment is calculated, and the cooling system parameters are designed accordingly. Cooling components are then selected based on the cooling system parameters.

[0014] Furthermore, based on the top-level performance requirements of the train, the methods for designing the top-level parameters of the traction system include:

[0015] Receive and analyze the top-level performance requirements of the train;

[0016] Based on the aforementioned top-level performance requirements, the maximum wheel circumference traction force required by the train and its inflection point are determined, and the corresponding electric braking force is calculated.

[0017] Based on the preliminary estimates of the maximum wheel circumference traction force and electric braking force, a functional relationship between acceleration and deceleration and the top-level design parameters of the traction system is established.

[0018] Based on existing data and relationships, key speed nodes are set using speed-time curves, and the location and magnitude of the inflection points of the vehicle's traction force and electric braking force are calculated.

[0019] The number of motors and the gear ratio are selected based on the location and magnitude of the inflection points of the vehicle's traction force and electric braking force.

[0020] Furthermore, based on the top-level parameters, a relationship model between the weight and noise of the traction system equipment is established. Weighted analysis of lightweighting and noise factors is performed, and methods for adjusting the top-level design parameters include:

[0021] Define the maximum wheel circumferential traction force and maximum electric braking force of the traction system, and determine the maximum operating speed, number of motors, and gear ratio of the traction system;

[0022] Construct models to reflect the impact of equipment weight and equipment noise.

[0023] By combining the equipment weight impact model and the equipment noise impact model, a comprehensive evaluation function is calculated. This comprehensive evaluation function performs a weighted analysis of the weight ratios of equipment weight and system noise to obtain an overall evaluation result.

[0024] Adjust the top-level design parameters of the traction system to minimize the evaluation results.

[0025] Furthermore, the formula for calculating the current curve of the traction system during operation is as follows:

[0026] ;

[0027] in, This is the current operating current of the device. The relationship between the top-level parameters of the traction system and the current curve. For the operating conditions of the traction system, For maximum wheel circumference traction, This is the inflection point of the vehicle's traction force. Indicates the maximum electric braking force. Indicates the inflection point of the vehicle's electric braking force. For the number of motors, This is the gear transmission ratio. For the weight of the train, For trailer weight, This is the train running resistance curve. This refers to the train's location. Indicates time; Represents high-speed trains. Represents a trailer;

[0028] The formula for calculating the equipment operating loss curve is:

[0029] ;

[0030] in, The relationship between the top-level parameters of the traction system and the working loss curve; A curve representing the change of the device's operating current over time; that is, current as a function of time. The function;

[0031] After obtaining the equipment working loss curve, the fan air volume parameters are designed based on the highest ambient temperature and altitude of the actual operating location of the traction system.

[0032] The formula for calculating air volume is as follows:

[0033] ;

[0034] In the formula, For fan air volume, The relationship between the top-level parameters of the traction system and the air volume. The highest operating ambient temperature at the location where the traction system operates. This refers to the highest operating altitude of the traction system's location. The curve representing the change in power loss of a device over time is a time-varying curve. The function;

[0035] The cooling system fan is selected and designed based on the fan air volume parameters.

[0036] Furthermore, the method also includes: establishing the relationship between the switching frequency and inductance of the traction electrical equipment and the electromagnetic noise of the traction system by adjusting the switching frequency and inductance value of the equipment; evaluating the impact of the adjusted switching frequency and inductance value on the weight of the traction system equipment; and determining the final switching frequency and inductance value by achieving an optimal balance between electromagnetic noise and equipment weight through a comprehensive weighting method.

[0037] Furthermore, methods for establishing the relationship between the switching frequency of electrical equipment, the inductance value of the equipment, and the electromagnetic noise of the traction system include:

[0038] Establish the relationship between the switching frequency of electrical equipment, the inductance value of the equipment, and the electromagnetic noise of the traction system through simulation or experimentation;

[0039] The parameter combination that minimizes the impact on electromagnetic noise is determined using the following formula:

[0040] ;

[0041] in, Electromagnetic noise, This relates to the relationship between electromagnetic noise in a traction system, the switching frequency of electrical equipment, and the inductance values ​​of each piece of equipment. Indicates the switching frequency of the traction electrical equipment. These are the inductance values ​​for each device.

[0042] Furthermore, methods for evaluating the impact of adjusted switching frequency and inductance values ​​on the weight of traction system equipment include:

[0043] Calculate the change in equipment weight using the following formula:

[0044] ;

[0045] in, For equipment weight, This relates the weight of equipment in the traction system to the switching frequency of electrical equipment and the inductance value of each piece of equipment.

[0046] Furthermore, methods for adjusting the weights include:

[0047] Determine the scoring formula for electromagnetic noise and equipment weight;

[0048] Based on the design requirements of different implementation cases, set the initial weight ratio coefficient in the scoring formula;

[0049] Substitute the initial weight ratio coefficients into the scoring formula to evaluate the changes in the objective function under different weight combinations, and record the corresponding switching frequency and inductance value.

[0050] Under the premise of meeting the design constraints, the objective function is optimized to achieve the expected results by adjusting the initial weight coefficients, and the final switching frequency and inductance value are determined.

[0051] To achieve the above objectives, a second aspect of the present invention provides a processor for running a program, wherein the program executes the noise reduction design method for the traction system of a rail transit vehicle.

[0052] To achieve the above objectives, a third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the aforementioned noise reduction design method for a rail transit vehicle traction system.

[0053] The beneficial effects of this invention are:

[0054] Compared with existing technologies, this invention provides a noise reduction design method, processor, and storage medium for a rail transit vehicle traction system, solving the problems of aerodynamic and electromagnetic noise generated during traction system operation. It reduces noise from the design source to improve environmental friendliness and passenger comfort. First, in the top-level parameter design stage, key parameters affecting traction system noise are introduced, and a noise impact assessment mechanism is established to ensure that the system and noise are matched while meeting basic performance indicators. Second, by refining the design parameters of the traction system's cooling components, cooling and heat dissipation boundary conditions are rationally determined to avoid increased aerodynamic noise due to over-design of cooling equipment. Simultaneously, in terms of electromagnetic noise control in the traction system, the switching frequency of electrical equipment and the inductance value of magnetic components are identified and optimized, adjusting these factors to effectively reduce electromagnetic noise. Furthermore, this invention comprehensively considers the top-level design of the traction system, cooling component parameters, and electromagnetic noise-related parameters, performing a weighted evaluation of system lightweighting and noise to achieve the optimal design configuration. Through these methods, unnecessary performance redundancy in the traction system can be reduced, equipment weight can be lowered, thereby improving the lightweight performance of the traction system and significantly improving the environmental friendliness and passenger comfort of rail transit vehicles. Attached Figure Description

[0055] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0056] Figure 1 This is a flowchart of a noise reduction design method for a rail transit vehicle traction system disclosed in an embodiment of the present invention.

[0057] Figure 2 This is a flowchart of a top-level parameter and noise matching design for a traction system disclosed in an embodiment of the present invention.

[0058] Figure 3 This is a flowchart of a design for matching cooling parameters and noise levels of a traction system component, as disclosed in an embodiment of the present invention.

[0059] Figure 4 This is a flowchart of an electromagnetic noise matching design for a traction system disclosed in an embodiment of the present invention. Detailed Implementation

[0060] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0061] According to an embodiment of the present invention, a noise reduction design method for a traction system of a rail transit vehicle is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0062] The noise of the traction system can be divided into two categories: aerodynamic noise and electromagnetic noise.

[0063] Aerodynamic noise is a type of noise generated by the traction system during operation, primarily originating from the high-speed rotation of the fan and its impeller. When the traction system is working, there is a certain amount of power loss, which is typically dissipated as heat, thus requiring a cooling system for heat dissipation. The fan provides the power for heat exchange through high-speed operation, thereby releasing heat energy.

[0064] At low speeds, the cooling airflow is low, resulting in low aerodynamic noise. However, as the speed increases, both cooling airflow and aerodynamic noise increase linearly. Aerodynamic noise is typically closely related to impeller rotation, especially under high-speed, low-load conditions, where it becomes more pronounced. This noise is caused by the interaction between the asymmetric structure around the blades and the circumferentially non-uniform flow field created by the blade rotation.

[0065] The main sources of aerodynamic noise include:

[0066] 1. Intake noise caused by air intake interference due to the guide vanes or metal mesh cover in front of the air inlet;

[0067] 2. Rotational frequency noise generated by blade rotation in an uneven or asymmetrical casing;

[0068] 3. Exit interference noise generated at the centrifugal air outlet due to the volute or the guide vanes of the axial flow fan.

[0069] Electromagnetic noise is the noise generated in a traction system when the motor and multiple magnetic components (such as transformers and reactors) are energized. Taking the motor as an example, electromagnetic noise originates from the temporal and spatial changes within the motor, as well as the magnetic pull caused by the interaction between its various parts.

[0070] When the motor is running, an air gap magnetic field is formed in the air gap space between the stator and the rotor, generating a rotating force wave. This electromagnetic force is alternating. During the operation of the traction motor, the rotating force wave formed by the air gap magnetic field acts on both the stator and the rotor, causing them to deform and vibrate periodically, thus generating a sound source.

[0071] Electromagnetic noise is mainly caused by the vibration of the iron core due to magnetostriction of the silicon steel sheets under the influence of an alternating magnetic field during the power conversion process of the traction system. In addition, the switching operation of power electronic devices is also a major source of electromagnetic noise.

[0072] Comparing aerodynamic noise and electromagnetic noise, the aerodynamic noise generated by the fan rotation is significantly greater, while electromagnetic noise is much smaller. However, when the train is running at low speeds, the aerodynamic noise decreases, and the noise from the traction system becomes primarily electromagnetic noise.

[0073] Based on the above analysis, the purpose of this invention is specifically to address the noise problem of traction systems. When designing traction system components (traction transformer, traction converter, traction motor), a coupling relationship between system parameters and noise is established. Through system matching design and optimization, while meeting the operational requirements of the traction system, the aerodynamic and electromagnetic noise generated by the traction system itself is reduced from the design perspective, thereby achieving the goal of simultaneously reducing noise inside and outside the vehicle.

[0074] In response to the aerodynamic and electromagnetic noise of the traction system, the noise reduction design method of the rail transit vehicle traction system of the present invention carries out noise reduction matching design in the traction system design, so that the designed traction system has the characteristics of low electromagnetic and aerodynamic noise. The solution of the present invention will be described in detail below.

[0075] The flowchart of the noise reduction design method for rail transit vehicle traction system is as follows: Figures 1-4 As shown, this invention provides a noise reduction design method for a rail transit vehicle traction system, comprising the following steps:

[0076] Step S100: Design the top-level parameters of the traction system based on the top-level performance requirements of the train.

[0077] Generally, the traction system needs to be designed for traction / electric braking performance based on the top-level design requirements of the rail transit vehicle, which is also the basis for the detailed technical design of the entire traction system. The design of the top-level parameters depends on the train parameters and performance requirements.

[0078] Train parameters include: train speed rating (km / h), train weight Trailer weight Train rotational inertia coefficient Train running resistance curve It can be based on the current speed of the train. Determine the overall vehicle resistance and train starting acceleration requirements. (m / s 2 Train average acceleration requirements (m / s 2 Train average deceleration requirements (m / s 2 ).

[0079] Based on the above train parameters and performance requirements, the top-level parameter design of the traction system is carried out. The top-level parameters mainly include: the maximum wheel circumferential traction force of the entire vehicle. Inflection point of vehicle traction Maximum electric braking force of the whole vehicle Inflection point of vehicle electric braking force Number of train motors Gear transmission ratio .

[0080] The top-level parameter design of the traction system is the foundation of the entire traction system design. Traction system performance and detailed component design are all based on this top-level design; therefore, traction system noise must be considered as a system design requirement during the top-level design phase. On one hand, from the perspective of detailed traction system design, while designing excessively high traction forces / inflection points can significantly improve train performance, excessively pursuing performance (such as system power ratings) will lead to the system failing to achieve the designed performance in actual use, resulting in design redundancy and waste. On the other hand, from the perspective of train noise analysis, as train speed increases, equipment noise typically increases significantly. Therefore, the compatibility between the top-level design parameters and noise reduction design requirements must be considered at the outset of the traction system design.

[0081] First, the impact of the designed traction system on weight reduction and noise needs to be evaluated based on the top-level design parameters, and the following functional mapping relationship needs to be established from the design perspective:

[0082] ;

[0083] ;

[0084] ;

[0085] in, To initiate acceleration, For average acceleration, For average deceleration, For maximum wheel circumference traction, Indicates the maximum electric braking force. This is the train's maximum operating speed. This is the inflection point of the vehicle's traction force. Indicates the inflection point of the vehicle's electric braking force. For the weight of the train, For trailer weight, The train's moment of inertia coefficient. This is the train running resistance curve. Represents high-speed trains. It represents a trailer.

[0086] —This represents the influence of the top-level parameters of the traction system on the starting acceleration, which can be derived theoretically. , , These are inherent parameters of the vehicle. Since it is a constant, it is necessary to determine whether the acceleration can be satisfied during the top-level design of the traction system. , The required traction force and electric braking force are obviously related to the maximum wheel circumference traction force, which will obviously increase the starting acceleration accordingly.

[0087] —This represents the influence of the top-level parameters of the traction system on the average acceleration, which can be derived theoretically. The relationship is related to… Similarly, average acceleration depends on the maximum traction force and the increase in the traction inflection point.

[0088] —This represents the influence of the top-level parameters of the traction system on the average deceleration, which can be derived theoretically. The relationship is related to… Similarly, average deceleration depends on the increase in maximum electric braking force and the inflection point of electric braking force.

[0089] During the design process, care should be taken to ensure that the traction force and electric braking force are not too large, and their design should just meet the acceleration requirements. , , The requirements should be met, but a certain margin should be left.

[0090] Step S200: Establish a relationship model between the weight and noise of the traction system equipment based on the top-level parameters, perform a weighted analysis of lightweighting and noise factors, and adjust the top-level design parameters to minimize the evaluation results;

[0091] Having determined the traction force, electric braking force, and their respective inflection points, the power rating of the entire traction system has been established. The relationship between the weight and noise of the traction system equipment is as follows:

[0092] ;

[0093] ;

[0094] in, For the weight of the traction system equipment. For traction system noise, For maximum wheel circumference traction and maximum electric braking force, This is the maximum operating speed of the traction system. For the number of motors, This is the gear transmission ratio.

[0095] —This indicates the relationship between the top-level parameters of the traction system and the weight. The larger the number of motors, the heavier the traction system. This can be derived theoretically or through existing simulation calculations. Generally speaking, increasing the number of motors (i.e., increasing the train's power-to-tow ratio) will reduce the average power rating of individual equipment, thus reducing the weight of individual equipment. Increasing the gear ratio... This mainly reduces the output torque of the equipment, lowers the requirements for the output capacity of the equipment, and will also reduce the weight of the traction system equipment to some extent. However, increasing the transmission ratio will also lead to an increase in the maximum speed of the motor.

[0096] —This indicates the relationship between the top-level parameters of the traction system and the noise. The larger the gear ratio, the greater the noise in the traction system; this can be derived theoretically or through existing simulation calculations. Increasing the gear ratio... This will significantly increase the motor speed, and for self-ventilated motors, the increase in motor speed will lead to an increase in motor noise.

[0097] It should be noted that in a self-ventilated motor, the motor has its own coaxial fan and external air duct for self-ventilated cooling. The centrifugal fan is coaxially mounted with the motor rotor and is driven to rotate by the motor rotor. As the fan rotates, outside air passes through the motor's interior and is exhausted through the ventilation duct outlet, dissipating heat at the motor's internal surfaces through the flow of ambient air.

[0098] After determining the relationship between the weight and noise of the traction system equipment, and considering the overall performance of the traction system, the following formula can be used for evaluation:

[0099]

[0100] in, For the evaluation results, The weight percentage of the equipment weight. This represents the weighting percentage of system noise; if the system design prioritizes lightweight design, then... The value is relatively large. The value is smaller; conversely, if the importance of system noise is emphasized, then... The value is relatively small. With a relatively large value, the impact of lightweighting and noise on the traction system is comprehensively evaluated using the above formula. When the final evaluation result is... When the minimum value is reached, the optimal combination of top-level system indicators under the current design requirements can be obtained.

[0101] Understandably, when designing the traction system of a rail transit vehicle, the traction force and braking force, along with their related inflection points, are first determined, thus deriving the required power level for the entire system. However, in the actual design process, a trade-off must be struck between equipment weight and noise. Specifically, the top-level parameters of the traction system (such as maximum traction force, maximum speed, number of motors, and gear ratio) affect the weight of the equipment (through...). (function) and noise (through) (Function). Increasing the number of motors usually reduces the power requirement of a single device, thus reducing weight; while increasing the gear ratio may also reduce the output requirements of the device and reduce weight, but at the same time, it will increase the maximum speed of the motor, which may increase noise. To find the optimal balance, this method uses a comprehensive evaluation formula. ,in and These represent the relative importance of weight and noise in the design, respectively. If the system prioritizes lightweight design, The setting should be relatively large; if more attention is paid to noise control, Therefore, the value is set relatively large. Ultimately, the evaluation value is minimized. This will help find the optimal combination of parameters that meets design requirements.

[0102] Step S300: Based on the adjusted top-level design parameters, combined with the traction system's operating line conditions, maximum operating ambient temperature, and altitude, simulate the actual operating state of the traction system and calculate the current curve of the traction system during operation.

[0103] Understandably, after determining the top-level design parameters of the rail transit vehicle traction system, further parametric design of the traction system components is required. Since fans and their impellers are the main sources of noise in the traction system (because they are responsible for cooling the equipment), the key to reducing noise lies in the refined design of these cooling components. Over-designing the cooling equipment can lead to unnecessary noise and performance redundancy; therefore, cooling requirements need to be accurately determined based on actual operating conditions. Considering that train operating lines are usually relatively fixed, this design process needs to consider some important parameters: such as line conditions (e.g., gradient, curves, and station information), maximum ambient temperature, and altitude. Based on this, the current curve of the equipment is obtained by simulating the train's operating current curve. This information is used to calculate the equipment's operating losses and then determine the required cooling system parameters (e.g., fan airflow). This method ensures that the cooling system matches the actual operating conditions of the equipment, thereby effectively reducing noise and achieving optimized design while meeting the requirements of the traction system. This will be explained in detail below:

[0104] To achieve refined design of the cooling and heat dissipation performance of the traction system, the cooling and heat dissipation boundary conditions should be scientifically and rationally determined based on the actual operating conditions of the traction system. Considering that rail transit lines are typically relatively fixed, the required parameters for refined design of the cooling and heat dissipation boundary conditions are as follows:

[0105] 1) Traction system operating line conditions According to the location of the train It can determine the current slope, curve, station information, etc.

[0106] 2) The highest operating ambient temperature at the location where the traction system operates. .

[0107] 3) The highest working altitude of the traction system's operating location .

[0108] Based on the above parameters and the top-level design parameters of the traction system, we first perform simulation calculations on the actual operation of the traction system to calculate the current curve during operation:

[0109] ;

[0110] in, This is the current operating current of the device. The relationship between the top-level parameters of the traction system and the current curve. For the operating conditions of the traction system, This refers to the train's location. Indicates time;

[0111] Step S400: Calculate the equipment working loss curve based on the obtained current curve and traction system working characteristics, and design the cooling system parameters accordingly, and select cooling components based on the cooling system parameters.

[0112] After obtaining the equipment working loss curve, the cooling system parameters, such as fan air volume, are designed based on the highest ambient temperature and altitude of the actual operating location of the traction system. Finally, the cooling system fan and motor fan are selected and designed based on the air volume.

[0113] ;

[0114] In the formula, For fan air volume, The relationship between the top-level parameters of the traction system and the air volume. The highest operating ambient temperature at the location where the traction system operates. This refers to the highest operating altitude of the traction system's location.

[0115] The above design ensures that the cooling components of the traction system are designed with precision based on the actual working conditions of the equipment. It ensures that the coupling relationship between system parameters and noise is established at the design stage. Through system matching design and optimization, the noise of the traction system cooling system is reduced from the design stage while meeting the operational requirements of the traction system.

[0116] When designing rail transit vehicles, in addition to considering the aerodynamic noise generated by cooling equipment, it is also necessary to consider the electromagnetic noise generated during power conversion, as this can affect passenger comfort. Electromagnetic noise is primarily related to the electrical switching frequency and the inductance of magnetic components (such as transformers and reactors). To understand and control this noise, the relationship between the switching frequency of electrical equipment, the inductance value of the equipment, and the electromagnetic noise of the traction system is established through simulation or experimentation. , The larger the value, the greater the electromagnetic noise.

[0117] ;

[0118] in, Electromagnetic noise, This relates to the relationship between electromagnetic noise in a traction system, the switching frequency of electrical equipment, and the inductance values ​​of each piece of equipment. Indicates the switching frequency of the traction electrical equipment. These are the inductance values ​​for each device.

[0119] By adjusting the switching frequency and inductance value within a reasonable range, the electromagnetic noise of the traction system during operation can be effectively reduced. However, this adjustment may result in significant differences from the original solution; therefore, it is necessary to evaluate the impact of these parameter adjustments on the weight of the traction system equipment, expressed as... Larger This means higher equipment weight:

[0120] ;

[0121] in, For equipment weight, This relates the weight of equipment in the traction system to the switching frequency of electrical equipment and the inductance value of each piece of equipment.

[0122] Finally, electromagnetic noise needs to be comprehensively considered in the design. and equipment weight The optimal design scheme for the traction system under different switching frequencies and inductance values ​​is determined by weighing the trade-offs between these factors. A comprehensive evaluation is performed using the following weighted formula:

[0123] ;

[0124] in, and These represent the weights of electromagnetic noise and equipment weight, respectively. By adjusting the weighting coefficients, an optimal balance between noise and weight can be found for different application scenarios.

[0125] In the method of the present invention, by introducing key parameters that affect the noise of the traction system during the design process and establishing a noise impact assessment, system performance design and system noise matching design are carried out at the design end, thereby achieving the goal of reducing the noise of the traction system from the source of noise.

[0126] Furthermore, while traction systems are designed according to relevant standards, parameters such as rated point, ambient temperature, and altitude often lead to design redundancy and waste, such as when the actual operating ambient temperature or altitude does not meet the most stringent standard requirements. The method of this invention utilizes the characteristic that rail transit vehicles typically operate on fixed lines, using the actual operating conditions and environment of the traction system as design inputs to conduct a refined design evaluation of the traction system's operating loss characteristics, further optimizing the cooling system design parameters, thereby achieving the goal of reducing the noise of the traction system's cooling system.

[0127] To address electromagnetic noise in traction systems, the method of this invention identifies key influencing factors and establishes a matching relationship between the switching frequency of electrical equipment, the inductance value of magnetic components, and noise. This optimizes the design of the electromagnetic noise in the traction system. Implementing the design method of this invention can effectively reduce electromagnetic noise in traction systems and further improve the ride comfort of rail transit vehicles.

[0128] Regarding the overall performance of the traction system, the method of this invention establishes the relationship between the top-level design parameters of the traction system, cooling component parameters, electromagnetic noise-related parameters, and system noise and weight, and performs a weighted comprehensive evaluation of the impact of traction system design on lightweighting and noise. By comprehensively evaluating the impact of each design parameter of the traction system on system lightweighting and noise, different weighting coefficients can be selected for different project requirements, thereby achieving a focus on lightweighting or noise at the front end of traction system design.

[0129] In addition, by using a refined loss assessment method, redundant performance design can be avoided when designing traction system components, maximizing the utilization of traction system performance, reducing equipment weight, and improving the lightweight performance of the traction system.

[0130] According to another aspect of the embodiments of this application, a processor is also provided, which is used to run a program, wherein a noise reduction design method for a rail transit vehicle traction system is executed when the program is running.

[0131] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0132] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0133] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0134] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0135] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A noise reduction design method for a rail transit vehicle traction system, characterized in that, Includes the following steps: Based on the train performance requirements, the top-level parameters of the traction system are designed. These top-level parameters include: the maximum wheel circumference traction force of the whole vehicle, the inflection point of the traction force of the whole vehicle, the maximum electric braking force of the whole vehicle, the inflection point of the electric braking force of the whole vehicle, the number of train motors, and the gear transmission ratio. Based on the top-level parameters, a model relating the weight and noise of the traction system equipment is established. Weighted analysis of lightweighting and noise factors is performed, and the top-level design parameters are adjusted to minimize the evaluation results. Based on the adjusted top-level design parameters, combined with the traction system's operating line conditions, maximum operating ambient temperature, and altitude, the actual operating state of the traction system is simulated, and the current curve of the traction system during operation is calculated. Based on the obtained current curve and the working characteristics of the traction system, the working loss curve of the equipment is calculated, and the cooling system parameters are designed accordingly. Cooling components are then selected based on the cooling system parameters. Based on the top-level parameters, a model relating the weight and noise of the traction system equipment is established. Weighted analysis of lightweighting and noise factors is performed, and methods for adjusting the top-level design parameters include: Define the maximum wheel circumferential traction force and maximum electric braking force of the traction system, and determine the maximum operating speed, number of motors, and gear ratio of the traction system; Construct models to reflect the impact of equipment weight and equipment noise. By combining the equipment weight impact model and the equipment noise impact model, a comprehensive evaluation function is calculated. This comprehensive evaluation function performs a weighted analysis of the weight ratios of equipment weight and system noise to obtain an overall evaluation result. Adjust the top-level design parameters of the traction system to minimize the evaluation results; The formula for calculating the current curve of the traction system during operation is as follows: ； in, This is the current operating current of the device. The relationship between the top-level parameters of the traction system and the current curve. For the operating conditions of the traction system, For maximum wheel circumference traction, This is the inflection point of the vehicle's traction force. Indicates the maximum electric braking force. Indicates the inflection point of the vehicle's electric braking force. For the number of motors, This is the gear ratio. For the weight of the train, For trailer weight, This is the train running resistance curve. This refers to the train's location. Indicates time, Represents high-speed trains. Represents a trailer; The formula for calculating the equipment operating loss curve is: ； in, The relationship between the top-level parameters of the traction system and the working loss curve; A curve representing the change of the device's operating current over time; that is, current as a function of time. The function; After obtaining the equipment working loss curve, the fan air volume parameters are designed based on the highest ambient temperature and altitude of the actual operating location of the traction system. The formula for calculating air volume is as follows: ； In the formula, For fan air volume, The relationship between the top-level parameters of the traction system and the air volume. The highest operating ambient temperature at the location where the traction system operates. This refers to the highest operating altitude of the traction system's location. The curve representing the change in power loss of a device over time is a time-varying curve. The function; The cooling system fan is selected and designed based on the fan air volume parameters.

2. The noise reduction design method for rail transit vehicle traction system as described in claim 1, characterized in that, The methods for designing the top-level parameters of the traction system based on the top-level performance requirements of the train include: Receive and analyze the top-level performance requirements of the train; Based on the aforementioned top-level performance requirements, the maximum wheel circumference traction force required by the train and its inflection point are determined, and the corresponding electric braking force is calculated. Based on the preliminary estimates of the maximum wheel circumference traction force and electric braking force, a functional relationship between acceleration and deceleration and the top-level design parameters of the traction system is established. Based on existing data and relationships, key speed nodes are set using speed-time curves, and the location and magnitude of the inflection points of the vehicle's traction force and electric braking force are calculated. The number of motors and the gear ratio are selected based on the location and magnitude of the inflection points of the vehicle's traction force and electric braking force.

3. The noise reduction design method for rail transit vehicle traction system as described in claim 1, characterized in that, The method further includes: establishing the relationship between the switching frequency and inductance of the traction electrical equipment and the electromagnetic noise of the traction system by adjusting the switching frequency and inductance value of the equipment; evaluating the impact of the adjusted switching frequency and inductance value on the weight of the traction system equipment; and determining the final switching frequency and inductance value by achieving an optimal balance between electromagnetic noise and equipment weight through a comprehensive weighting method.

4. The noise reduction design method for rail transit vehicle traction system as described in claim 3, characterized in that, Methods for establishing the relationship between the switching frequency of electrical equipment, the inductance value of the equipment, and the electromagnetic noise of the traction system include: Establish the relationship between the switching frequency of electrical equipment, the inductance value of the equipment, and the electromagnetic noise of the traction system through simulation or experimentation; The parameter combination that minimizes the impact on electromagnetic noise is determined using the following formula: ； in, Electromagnetic noise, This relates to the relationship between electromagnetic noise in a traction system, the switching frequency of electrical equipment, and the inductance values ​​of each piece of equipment. Indicates the switching frequency of the traction electrical equipment. These are the inductance values ​​for each device.

5. The noise reduction design method for rail transit vehicle traction system as described in claim 4, characterized in that, Methods for assessing the impact of adjusted switching frequency and inductance values ​​on the weight of traction system equipment include: Calculate the change in equipment weight using the following formula: ； in, For equipment weight, This relates the weight of equipment in the traction system to the switching frequency of electrical equipment and the inductance value of each piece of equipment.

6. The noise reduction design method for rail transit vehicle traction system as described in claim 5, characterized in that, Methods for adjusting weights include: Determine the scoring formula for electromagnetic noise and equipment weight; Based on the design requirements of different implementation cases, set the initial weight ratio coefficient in the scoring formula; Substitute the initial weight ratio coefficients into the scoring formula to evaluate the changes in the objective function under different weight combinations, and record the corresponding switching frequency and inductance value. Under the premise of meeting the design constraints, the objective function is optimized to achieve the expected results by adjusting the initial weight coefficients, and the final switching frequency and inductance value are determined.

7. A processor, characterized in that, The processor is used to run a program, wherein the program executes the noise reduction design method for the traction system of rail transit vehicles according to any one of claims 1 to 6.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps of the noise reduction design method for the traction system of rail transit vehicles as described in any one of claims 1 to 6.

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