Wire harness radiation simulation method and system based on magnetic ring impedance frequency response characteristics

Abstract

The invention relates to a wire harness radiation simulation method and system based on magnetic ring impedance frequency response characteristics. Measurement points are selected around an electromagnetic simulation coupling model about a magnetic ring, a wire harness and a metal structure around the wire harness; the excitation condition data and the impedance characteristic notepad document of the magnetic ring are input for simulation analysis, a curve chart of the first electric field radiation value of the measuring point changing along with the frequency is obtained, the magnetic ring does not need to be arranged on the whole vehicle for actual verification in the process, and the impedance frequency response characteristic curve of the magnetic ring is converted into the impedance characteristic notepad document; obtaining the electric field radiation values of the measuring points under different frequencies after the magnetic ring of the specification type is arranged; in addition, simulation can be carried out again after the specification and the installation position of the magnetic ring are modified, so that the specification and the installation position of the magnetic ring meeting requirements are quickly determined, and the test time is shortened; results of simulation analysis provide references for modification and adjustment of specifications and installation positions, so that modification randomness is avoided, and certain guidance is provided for direct-current fast-charging wire harness electromagnetic radiation standard-exceeding rectification.

Description

Technical Field

[0001] The present application relates to the field of automobile electromagnetic compatibility design, and in particular to a wiring harness radiation simulation method and system based on the frequency response characteristics of magnetic ring impedance. Background Art

[0002] With the electrification of new energy vehicles, battery packs are standard for new energy vehicles. The capacity of battery packs is increasing, and the driving range is thus longer. Each battery pack has its own independent charging system, which is divided into two types: DC fast charging and conventional slow charging. The DC fast charging wiring harness is composed of two wires: positive wiring harness and negative wiring harness.

[0003] When new energy vehicles are fast charged with high current, the current in the positive and negative wiring harnesses will generate electromagnetic radiation to the surrounding environment. Especially when the whole vehicle is charging, the electric field value radiated to the surrounding environment will exceed the standard limit.

[0004] The DC fast charging positive and negative wiring harnesses are connected to the charging pile on the ground at one end and the onboard charger system OBC in the new energy vehicle at the other end. When the DC fast charging causes the radiation to exceed the standard, the charging pile and the onboard charger cannot be changed, modified, or repaired. At this time, the DC fast charging wiring harness, as the transmission path of one of the three elements of electromagnetic compatibility, the positive wiring harness and the negative wiring harness are the rectification objects of the electromagnetic radiation bidding.

[0005] The three conventional methods of automobile electromagnetic compatibility rectification are filtering, grounding, and shielding. Adding a shielding layer and grounding will lead to high rectification costs; while the filtering method often adds a magnetic ring and uses the impedance characteristics of the magnetic ring to reduce electromagnetic radiation. It is a low-cost and effective measure.

[0006] Generally, a magnetic ring is added to the actual wiring harness, and then the excitation is set to excite the entire vehicle at the selected frequency for actual testing. However, there are the following problems:

[0007] (1) How to determine the location of the additional magnetic ring requires multiple changes in testing, such as whether to add a magnetic ring to the positive wiring harness or the negative wiring harness, or whether the magnetic ring is close to the battery pack side or the side close to the ground charging pile. The test time is high and has a certain degree of randomness.

[0008] (2) How to determine which frequency is most effective in reducing electromagnetic radiation, and how to select magnetic rings of different models and performances to achieve the best effect in reducing electromagnetic radiation requires multiple tests.

[0009] Therefore, a wiring harness radiation simulation method and system based on the frequency response characteristics of magnetic ring impedance is provided to solve the above problems. In order to provide certain guidance experience for the rectification of excessive electromagnetic radiation of a DC fast charging wiring harness and reduce testing time and cost. Summary of the invention

[0010] The embodiments of the present application provide a wiring harness radiation simulation method and system based on the frequency response characteristics of the magnetic ring impedance, so as to solve the problem in the related art that multiple tests are required to determine whether the magnetic ring meets the electromagnetic radiation suppression requirements during the electromagnetic compatibility rectification of the automobile, resulting in high test time cost and a certain degree of randomness.

[0011] In a first aspect, a wire harness radiation simulation method based on the frequency response characteristics of magnetic ring impedance is provided, which comprises the following steps:

[0012] Establish electromagnetic simulation coupling model for magnetic ring, wiring harness and metal structure around the wiring harness;

[0013] Selecting measurement points around the electromagnetic simulation coupling model;

[0014] The excitation condition data and the impedance characteristic notebook document of the magnetic ring are used as simulation input data, and then an electromagnetic simulation analysis is performed in combination with an electromagnetic simulation coupling model to output a curve graph of the first electric field radiation value of the measuring point varying with frequency.

[0015] In some embodiments, after obtaining the curve diagram of the first electric field radiation value changing with frequency, the following steps are also included:

[0016] The magnetic ring in the electromagnetic simulation coupling model is removed, and then only the excitation condition data is used as the simulation input data, and then the electromagnetic simulation analysis is performed in combination with the electromagnetic simulation coupling model to obtain a curve diagram of the second electric field radiation value changing with frequency;

[0017] The second electric field radiation value versus frequency variation curve graph and the first electric field radiation value versus frequency variation curve graph are compared to obtain the electric field radiation reduction values ​​at different operating frequencies after the magnetic ring is added.

[0018] In some embodiments, establishing an electromagnetic simulation coupling model for a magnetic ring, a wire harness, and a metal structure around the wire harness includes the following steps:

[0019] Establish a three-dimensional electric field simulation model for the magnetic ring, wiring harness, and metal structure around the wiring harness;

[0020] A wiring harness topology simulation model for the wiring harness is established, and then a variable impedance module corresponding to the magnetic ring is added to the wiring harness topology simulation model to form a new wiring harness topology simulation model;

[0021] The three-dimensional electric field simulation model and the new wiring harness topology simulation model are coupled to form an electromagnetic simulation coupling model.

[0022] In some embodiments, establishing a three-dimensional electric field simulation model of a magnetic ring, a wiring harness, and a metal structure around the wiring harness specifically includes the following steps:

[0023] Establishing a wiring harness grid unit according to the distribution track of the wiring harness in the actual vehicle coordinates and the corresponding coordinate information; the wiring harness includes a positive wiring harness and a negative wiring harness;

[0024] Establishing a wire harness model based on the wire harness grid unit and in combination with the size data and material data of the wire harness;

[0025] Adding a magnetic ring unit at the design position of the wiring harness model to update the wiring harness model;

[0026] A three-dimensional model is established according to the dimension data of the metal structure around the wiring harness, and then the updated wiring harness model is combined with the three-dimensional model to obtain the three-dimensional electric field simulation model.

[0027] In some embodiments, establishing a wiring harness topology simulation model for the wiring harness specifically includes the following steps:

[0028] Establish a first excitation line topology model and establish a topology harness segment corresponding to the positive wiring harness; the first excitation line topology model includes a first part and a second part; the first part includes sequentially connecting a first connection joint, a first resistor, an excitation source topology model and a first grounding terminal; the second part includes sequentially connecting a second connection joint, a second resistor and a second grounding terminal;

[0029] Connecting two ends of the topology harness segment corresponding to the positive harness to the first connection joint and the second connection joint respectively to form a positive harness topology simulation model;

[0030] Establish a second excitation line topology model and establish a topology harness segment corresponding to the negative wiring harness; the second excitation line topology model includes a first part and a second part; the first part includes sequentially connecting a first connection joint, a first resistor, an excitation source topology model and a first grounding terminal; the second part includes sequentially connecting a second connection joint, a second resistor and a second grounding terminal;

[0031] Connecting two ends of the topology harness segment corresponding to the negative harness to the first connection joint and the second connection joint respectively to form a negative harness topology simulation model;

[0032] The positive wiring harness topology simulation model and the positive wiring harness topology simulation model are used as the wiring harness topology simulation model of the wiring harness.

[0033] In some embodiments, the magnetic ring is disposed on a side of the negative wiring harness close to the vehicle battery pack.

[0034] In some embodiments, the dimension data includes the geometric radius and thickness of the core wire and insulation layer of the wiring harness; the material data includes conductivity, relative dielectric constant and loss tangent.

[0035] In some embodiments, obtaining the impedance characteristic notepad file includes the following steps:

[0036] Obtaining an impedance frequency response characteristic curve of the magnetic ring, and reading out multiple sets of characteristic data; each set of characteristic data includes an impedance value and a frequency corresponding to the impedance value in the impedance frequency response characteristic curve;

[0037] Multiple groups of characteristic data are numbered and sorted to form an impedance characteristic notepad document.

[0038] In a second aspect, a wire harness radiation simulation system based on the frequency response characteristics of magnetic ring impedance is provided, which includes:

[0039] The first module is used to establish an electromagnetic simulation coupling model of a magnetic ring, a wiring harness, and a metal structure around the wiring harness;

[0040] The second module is used to select measurement points around the electromagnetic simulation coupling model;

[0041] The third module is used to use the excitation condition data and the impedance characteristic notebook document of the magnetic ring as simulation input data, and then perform electromagnetic simulation analysis in combination with the electromagnetic simulation coupling model to output a curve graph of the first electric field radiation value of the measuring point varying with the frequency; the magnetic ring simulation input data includes the impedance characteristic notebook document of the magnetic ring.

[0042] In some embodiments, a fourth module is further included, which is used to automatically call the impedance characteristic notepad document and combine it with the excitation condition data to form the simulation input data; the fourth module is also used to modify and store the impedance characteristic notepad document and the excitation condition data.

[0043] The beneficial effects of the technical solution provided by this application include:

[0044] The embodiment of the present application provides a harness radiation simulation method and system based on the impedance frequency response characteristics of a magnetic ring, wherein measuring points are selected around an electromagnetic simulation coupling model of a magnetic ring, a harness, and a metal structure around the harness; then, the excitation condition data and the impedance characteristic notebook document of the magnetic ring are input for simulation analysis to obtain a first electric field radiation value of the measuring point varying with frequency. The entire analysis process above does not require the magnetic ring to be set in an actual vehicle for verification. By using the impedance frequency response characteristic curve in the magnetic ring product manual and converting it into an impedance characteristic notebook document, the electric field radiation value of the measuring point at different frequencies after setting the magnetic ring of this specification type can be obtained, saving time for actual vehicle verification; in addition, the simulation input data and the electromagnetic simulation coupling model can be changed according to the specifications and installation positions of the magnetic ring, so that the specifications and installation positions of the magnetic ring that meet the requirements can be quickly determined, reducing the test time; furthermore, according to the first electric field radiation value varying with frequency, a reference standard can be given for modifying and adjusting the specifications and installation positions of the magnetic ring, thereby reducing the randomness of the modification and providing certain guidance for rectifying the excessive electromagnetic radiation of the DC fast charging harness. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0046] Figure 1 A wiring harness grid unit established according to the distribution trajectory of the wiring harness in the actual vehicle coordinates and the corresponding coordinate information provided in the embodiment of the present application;

[0047] Figure 2 A positive wiring harness topology simulation model provided in an embodiment of the present application;

[0048] Figure 3 A negative wiring harness topology simulation model with a magnetic ring provided in an embodiment of the present application;

[0049] Figure 4 A three-dimensional model established according to the size data of the metal structure around the wiring harness provided in an embodiment of the present application;

[0050] Figure 5 A curve diagram showing the variation of the first electric field radiation value with frequency provided in an embodiment of the present application;

[0051] Figure 6 A curve diagram showing the variation of the second electric field radiation value with frequency provided in an embodiment of the present application;

[0052] Figure 7 A schematic diagram of the general flow of a wiring harness radiation simulation method based on the magnetic ring impedance frequency response characteristics provided in an embodiment of the present application. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are 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 making creative work are within the scope of protection of this application.

[0054] It should be understood that:

[0055] Magnetic ring: The working principle of the magnetic ring is that it can absorb the energy of electromagnetic interference and convert it into heat energy for consumption, thereby achieving the purpose of reducing radiated interference. The factors affecting the working characteristics of the magnetic ring mainly include the magnetic permeability of the magnetic ring, the number of turns of the coil wrapped around the magnetic ring, the aperture of the magnetic ring, etc. When using it, it is necessary to use a suitable magnetic ring according to the frequency band where the radiation exceeds the standard. As long as the magnetic ring is put on the protected line, it does not need to be grounded. The bandpass characteristics of the magnetic ring can be used to effectively suppress the interference frequency band, and the desired effect can be achieved.

[0056] The magnetic ring can be roughly regarded as a series connection of resistance and inductance. They are all related to frequency and change with the change of frequency. At low frequency, the impedance is composed of the inductive reactance of the inductor. At high frequency, the impedance is composed of the resistance component. At this time, the resistance plays a major role, and the high-frequency noise energy will be converted into heat energy by the resistance and consumed. Different ferrite suppression components have different optimal suppression frequency ranges. Generally, the higher the magnetic permeability, the lower the suppression frequency.

[0057] During the electromagnetic compatibility EMI test, the problem of radiation exceeding the limit is often encountered. Magnetic rings can effectively solve the problem of radio frequency interference suppression of power lines, signal lines and connectors. They are simple to use, convenient, and do not take up much space, so they are widely used.

[0058] Generally, a magnetic ring is added to the actual wiring harness, and then the excitation is set to excite the entire vehicle at the selected frequency for actual testing. However, there are the following problems:

[0059] (1) How to determine the location of the additional magnetic ring requires multiple changes in testing, such as whether to add a magnetic ring to the positive wiring harness or the negative wiring harness, or whether the magnetic ring is close to the battery pack side or the side close to the ground charging pile. The test time is high and has a certain degree of randomness.

[0060] (2) How to determine which frequency is most effective in reducing electromagnetic radiation, and how to select magnetic rings of different models and performances to achieve the best effect in reducing electromagnetic radiation requires multiple tests.

[0061] In order to provide certain guidance experience for rectifying a DC fast charging harness that exceeds the electromagnetic radiation standard and reduce testing time and cost, the embodiment of the present application provides a harness radiation simulation method based on the frequency response characteristics of the magnetic ring impedance, so as to solve the problem in the related technology that multiple tests are required to determine whether the magnetic ring meets the electromagnetic radiation suppression requirements during the rectification of automobile electromagnetic compatibility, resulting in high testing time and cost and a certain degree of randomness.

[0062] First, see Figure 1-7 , a wire harness radiation simulation method based on the frequency response characteristics of magnetic ring impedance, comprising:

[0063] Step 100, establishing an electromagnetic simulation coupling model of a magnetic ring, a wiring harness, and a metal structure around the wiring harness;

[0064] Step 200, selecting measurement points around the electromagnetic simulation coupling model;

[0065] Step 300: Set the excitation condition data, the port excitation is a current with an amplitude of 60A.

[0066] and the impedance characteristic notebook document of the magnetic ring as simulation input data, and then electromagnetic simulation analysis is performed in combination with the electromagnetic simulation coupling model to output a curve diagram of the first electric field radiation value of the measuring point varying with the frequency; the magnetic ring simulation input data includes the impedance characteristic notebook document of the magnetic ring.

[0067] The entire analysis process above does not require the magnetic ring to be set in the actual vehicle for verification. By using the impedance frequency response characteristic curve in the magnetic ring product manual and converting it into an impedance characteristic notepad document, the electric field radiation value of the measuring point at different frequencies after setting the magnetic ring of this specification type can be obtained, saving the time for actual vehicle verification; in addition, the simulation input data and electromagnetic simulation coupling model can be changed according to the specifications and installation positions of the magnetic ring, so as to quickly determine the specifications and installation positions of the magnetic ring that meet the requirements and reduce the test time; furthermore, according to the first electric field radiation value changing with frequency curve, a reference standard can be given for modifying and adjusting the specifications and installation positions of the magnetic ring, thereby reducing the randomness of the modification and providing certain guidance for the rectification of the excessive electromagnetic radiation of the DC fast charging harness.

[0068] In addition, magnetic rings are widely used. Although magnetic rings can reduce radiation values ​​for some EMI tests, they are, after all, a remedial measure to the problem. If electromagnetic compatibility issues are considered when the product is designed, the occurrence of such problems will be reduced, saving the trouble of later rectification. Therefore, the wire harness radiation simulation method based on the impedance frequency response characteristics of the magnetic ring of this application can set the magnetic ring in the design stage to determine its installation position and the specifications of the magnetic ring.

[0069] In some preferred embodiments, step 400 is also included, referring to Figure 5 and Figure 6 Step 400, after obtaining the first electric field radiation value versus frequency variation curve, further comprising the following steps:

[0070] Cancel the magnetic ring in the electromagnetic simulation coupling model, and then only use the excitation condition data as the simulation input data, and then combine the electromagnetic simulation coupling model to perform electromagnetic simulation analysis to obtain the curve of the second electric field radiation value changing with frequency, see Figure 6 ;

[0071] The second electric field radiation value versus frequency variation curve graph and the first electric field radiation value versus frequency variation curve graph are compared to obtain the electric field radiation reduction values ​​at different operating frequencies after the magnetic ring is added.

[0072] Through the electric field radiation reduction value at different operating frequencies, we can know the strength of the magnetic ring shielding and which frequency has the best shielding, so that targeted rectification can be carried out.

[0073] In some preferred embodiments, step 100, establishing an electromagnetic simulation coupling model of a magnetic ring, a wiring harness, and a metal structure around the wiring harness, specifically includes the following steps:

[0074] Step 1001, establishing a three-dimensional electric field simulation model of a magnetic ring, a wiring harness, and a metal structure around the wiring harness; Step 1001, specifically comprising the following steps:

[0075] Step 1001-1, establish a wiring harness grid unit according to the distribution trajectory of the wiring harness in the actual vehicle coordinates and the corresponding coordinate information; refer to the attached Figure 1 The wiring harness includes the positive wiring harness Q and the negative wiring harness R. The S end is close to the battery pack side, and the T end is close to the motor side. Figure 1 The marking points on the center line are coordinate points. There are many coordinate points, and it would be messy to display all of them, so only a few coordinate points are selectively displayed here;

[0076] Step 1001-2: Establish a wire harness model based on the wire harness grid unit and in combination with the wire harness dimension data and material data; the dimension data includes the geometric radius and thickness of the core wire and insulation layer of the wire harness; the material data includes conductivity, relative dielectric constant and loss tangent.

[0077] Step 1001-3, adding a magnetic ring unit at the design position of the wiring harness model to update the wiring harness model;

[0078] Step 1001-4: Establish a three-dimensional model based on the size data of the metal structure around the wire harness, and then combine the updated wire harness model with the three-dimensional model to obtain a three-dimensional electric field simulation model. Figure 4 .

[0079] Step 1001 - 5 , using the positive wiring harness topology simulation model and the positive wiring harness topology simulation model as the wiring harness topology simulation model of the wiring harness.

[0080] Step 1002: Reference Figure 3 , establish a wiring harness topology simulation model for the wiring harness, and then add a variable impedance module corresponding to the magnetic ring in the wiring harness topology simulation model to form a new wiring harness topology simulation model; wherein, establishing the wiring harness topology simulation model for the wiring harness includes the following steps:

[0081] Step 1002-1, establish a first excitation line topology model and establish a topology harness segment corresponding to the positive wiring harness; the first excitation line topology model includes a first part and a second part; the first part includes sequentially connecting a first connection connector Cableconector2, a first resistor R2 (resistance value is 1Mohm), a positive excitation source topology model Port_P and a first ground terminal; the second part includes sequentially connecting a second connection connector Cableconector2, a second resistor R2 (resistance value is 50ohm) and a second ground terminal;

[0082] Step 1002-2: Connect the two ends of the topology harness segment corresponding to the positive harness to the first connection joint and the second connection joint respectively to form a positive harness topology simulation model. Figure 2 ;

[0083] Step 1002-3, establish a second excitation line topology model and establish a topology harness segment corresponding to the negative wiring harness; the second excitation line topology model includes a first part and a second part; the first part includes sequentially connecting the first connection connector Cableconector2, the first resistor R2 (resistance value is 1Mohm), the positive excitation source topology model Port_N and the first ground terminal; the second part includes sequentially connecting the second connection connector Cableconector2, the second resistor R2 (resistance value is 50ohm) and the second ground terminal;

[0084] Step 1002-4, connect the two ends of the topology harness segment corresponding to the negative harness to the first connection joint and the second connection joint respectively to form a negative harness topology simulation model. Figure 3 , refer to the attached Figure 3 It is in the form of a magnetic ring Z1.

[0085] Step 1003: Couple the three-dimensional electric field simulation model and the new wiring harness topology simulation model to form an electromagnetic simulation coupling model.

[0086] In some preferred embodiments, the above are all simulation tests of the installation position. After actual analysis and testing, it is found that the shielding effect of the magnetic ring set on the negative wiring harness close to the vehicle battery pack is the best, so that the harmonics in the current from the battery pack can be suppressed by the magnetic ring within a very short distance after passing through the negative cable, reducing the radiation emission of the negative wiring harness. At the same time, it is also convenient for the assembly of the magnetic ring. Therefore, for subsequent vehicles of the same type, when they are rectified, they only need to determine the specifications of the magnetic ring.

[0087] In some preferred embodiments, obtaining the impedance characteristic notepad document comprises the following steps:

[0088] Obtaining the impedance frequency response characteristic curve of the magnetic ring and reading out multiple sets of characteristic data; each set of characteristic data includes an impedance value and a frequency corresponding to the impedance value in the impedance frequency response characteristic curve;

[0089] Multiple groups of characteristic data are numbered and sorted to form an impedance characteristic notepad document.

[0090] This is because the impedance frequency response characteristic curve is included in the manual of each magnetic ring product, but it cannot be used directly for simulation. It needs to be converted to facilitate its call and participation in simulation.

[0091] In a second aspect, the present application provides a wire harness radiation simulation system based on the frequency response characteristics of magnetic ring impedance, which includes:

[0092] The first module is used to establish an electromagnetic simulation coupling model of a magnetic ring, a wiring harness, and a metal structure around the wiring harness;

[0093] The second module is used to select measurement points around the electromagnetic simulation coupling model;

[0094] The third module is used to use the excitation condition data and the impedance characteristic notebook document of the magnetic ring as simulation input data, and then perform electromagnetic simulation analysis in combination with the electromagnetic simulation coupling model to output a curve graph of the first electric field radiation value of the measuring point varying with the frequency; the magnetic ring simulation input data includes the impedance characteristic notebook document of the magnetic ring.

[0095] In some preferred embodiments, a fourth module is further included, which is used to automatically call the impedance characteristic notepad document and combine it with the excitation condition data to form simulation input data; the fourth module is also used to modify and store the impedance characteristic notepad document and the excitation condition data.

[0096] The scripting language for the fourth module is:

[0097]

[0098] The fourth module above can be easily modified and simulated. The input data can be changed directly through this module. That is, when one data changes and other data does not change, only the changed data needs to be resubmitted without repeated submission and input.

[0099] The functional implementation of each module in the above-mentioned wire harness radiation simulation system based on the frequency response characteristics of magnetic loop impedance corresponds to the steps in the above-mentioned wire harness radiation simulation method embodiment based on the frequency response characteristics of magnetic loop impedance, and their functions and implementation processes will not be repeated here one by one.

[0100] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit "first", "second" and "third" to different types.

[0101] In the description of the embodiments of the present application, "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a specific way.

[0102] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; the “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0103] In some processes described in the embodiments of the present application, multiple operations or steps that appear in a specific order are included, but it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of the present application or in parallel, and the sequence number of the operation is only used to distinguish the different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0104] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, disk, CD) as described above, and includes a number of instructions for a terminal device to execute the methods described in each embodiment of the present application.

[0105] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A wire harness radiation simulation method based on the frequency response characteristics of magnetic ring impedance, characterized in that: It includes the following steps: Establish electromagnetic simulation coupling model for magnetic ring, wiring harness and metal structure around the wiring harness; Selecting measurement points around the electromagnetic simulation coupling model; The excitation condition data and the impedance characteristic notebook document of the magnetic ring are used as simulation input data, and then an electromagnetic simulation analysis is performed in combination with an electromagnetic simulation coupling model to output a curve graph of the first electric field radiation value of the measuring point varying with frequency.

2. The wire harness radiation simulation method based on the magnetic ring impedance frequency response characteristic according to claim 1, characterized in that: After obtaining the curve diagram of the first electric field radiation value changing with frequency, the method further includes the following steps: The magnetic ring in the electromagnetic simulation coupling model is removed, and then only the excitation condition data is used as the simulation input data, and then the electromagnetic simulation analysis is performed in combination with the electromagnetic simulation coupling model to obtain a curve diagram of the second electric field radiation value changing with frequency; The second electric field radiation value versus frequency variation curve graph and the first electric field radiation value versus frequency variation curve graph are compared to obtain the electric field radiation reduction values ​​at different operating frequencies after the magnetic ring is added.

3. The wire harness radiation simulation method based on the magnetic ring impedance frequency response characteristics according to claim 1, characterized in that: Establishing an electromagnetic simulation coupling model of the magnetic ring, wire harness, and metal structure around the wire harness includes the following steps: Establish a three-dimensional electric field simulation model for the magnetic ring, wiring harness, and metal structure around the wiring harness; A wiring harness topology simulation model for the wiring harness is established, and then a variable impedance module corresponding to the magnetic ring is added to the wiring harness topology simulation model to form a new wiring harness topology simulation model; The three-dimensional electric field simulation model and the new wiring harness topology simulation model are coupled to form an electromagnetic simulation coupling model.

4. The wire harness radiation simulation method based on the magnetic ring impedance frequency response characteristic according to claim 3, characterized in that: Establishing a three-dimensional electric field simulation model of the magnetic ring, wiring harness, and metal structure around the wiring harness includes the following steps: Establishing a wiring harness grid unit according to the distribution track of the wiring harness in the actual vehicle coordinates and the corresponding coordinate information; the wiring harness includes a positive wiring harness and a negative wiring harness; Establishing a wire harness model based on the wire harness grid unit and in combination with the size data and material data of the wire harness; Adding a magnetic ring unit at the design position of the wiring harness model to update the wiring harness model; A three-dimensional model is established according to the dimension data of the metal structure around the wiring harness, and then the updated wiring harness model is combined with the three-dimensional model to obtain the three-dimensional electric field simulation model.

5. The wire harness radiation simulation method based on the magnetic ring impedance frequency response characteristic according to claim 4, characterized in that: Establishing a harness topology simulation model for a harness includes the following steps: Establish a first excitation line topology model and establish a topology harness segment corresponding to the positive wiring harness; the first excitation line topology model includes a first part and a second part; the first part includes sequentially connecting a first connection joint, a first resistor, an excitation source topology model and a first grounding terminal; the second part includes sequentially connecting a second connection joint, a second resistor and a second grounding terminal; Connecting two ends of the topology harness segment corresponding to the positive harness to the first connection joint and the second connection joint respectively to form a positive harness topology simulation model; Establish a second excitation line topology model and establish a topology harness segment corresponding to the negative wiring harness; the second excitation line topology model includes a first part and a second part; the first part includes sequentially connecting a first connection joint, a first resistor, an excitation source topology model and a first grounding terminal; the second part includes sequentially connecting a second connection joint, a second resistor and a second grounding terminal; Connecting two ends of the topology harness segment corresponding to the negative harness to the first connection joint and the second connection joint respectively to form a negative harness topology simulation model; The positive wiring harness topology simulation model and the positive wiring harness topology simulation model are used as the wiring harness topology simulation model of the wiring harness.

6. The wire harness radiation simulation method based on the magnetic ring impedance frequency response characteristic according to claim 5, characterized in that: The magnetic ring is sleeved on the negative pole wiring harness on a side close to the vehicle battery pack.

7. The wire harness radiation simulation method based on the magnetic ring impedance frequency response characteristic according to claim 4, characterized in that: The dimension data include the geometric radius and thickness of the core wire and insulation layer of the wiring harness; the material data include conductivity, relative dielectric constant and loss tangent.

8. The wire harness radiation simulation method based on the magnetic ring impedance frequency response characteristic according to claim 1, characterized in that: Obtaining the impedance characteristics notebook document involves the following steps: Obtaining an impedance frequency response characteristic curve of the magnetic ring, and reading out multiple sets of characteristic data; each set of characteristic data includes an impedance value and a frequency corresponding to the impedance value in the impedance frequency response characteristic curve; Multiple groups of characteristic data are numbered and sorted to form an impedance characteristic notepad document.

9. A wire harness radiation simulation system based on the frequency response characteristics of magnetic ring impedance, characterized in that: It includes: The first module is used to establish an electromagnetic simulation coupling model of a magnetic ring, a wiring harness, and a metal structure around the wiring harness; The second module is used to select measurement points around the electromagnetic simulation coupling model; The third module is used to use the excitation condition data and the impedance characteristic notebook document of the magnetic ring as simulation input data, and then perform electromagnetic simulation analysis in combination with the electromagnetic simulation coupling model to output a curve graph of the first electric field radiation value of the measuring point varying with the frequency; the magnetic ring simulation input data includes the impedance characteristic notebook document of the magnetic ring.

10. The wire harness radiation simulation system based on the magnetic ring impedance frequency response characteristic as claimed in claim 9, characterized in that: It also includes a fourth module, which is used to automatically call the impedance characteristic notepad document and combine it with the excitation condition data to form the simulation input data; the fourth module is also used to modify and store the impedance characteristic notepad document and the excitation condition data.

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