Method and system for testing matching degree of fuse and wire for automobile wire harness

Abstract

The invention discloses a method and system for testing the matching degree of a fuse and a wire for an automobile wire harness, and the method comprises the steps: collecting the physical parameters of the wire, the rated parameters of the fuse and a safety matching threshold value, synchronously collecting various parameters, such as aging, environment, load current and the like, calculating various correction factors, and correcting to obtain the dynamic current-carrying capability of the wire. And calculating a matching degree risk early warning index and a self-adaptive matching adjustment coefficient, executing an adjustment operation, and performing dynamic cycle monitoring. The system is correspondingly provided with multiple types of acquisition, calculation and adjustment modules. According to the scheme, the problem of coupling mismatching caused by static matching in the prior art is solved, dynamic accurate matching is achieved, and the use safety and stability of the automobile wire harness are guaranteed.

Description

Technical Field

[0001] This invention relates to the field of automotive electronics technology, and more specifically to a method and system for testing the matching degree of fuses and wires used in automotive wiring harnesses. Background Technology

[0002] As the core carrier of power transmission in a vehicle, the safety of automotive wiring harnesses directly determines the reliability of the entire vehicle's operation. Matching fuses and wires is crucial for ensuring wiring harness safety. Current technologies rely solely on static settings based on rated current and wire cross-sectional area at room temperature, neglecting the dynamic impact of multiple factors coupled during actual vehicle operation on the matching state. Over time, wire resistivity increases due to thermal aging, and the high-temperature environment in areas like the engine compartment further exacerbates the decline in wire current-carrying capacity. Simultaneously, electromagnetic interference generated by onboard radar, motors, and other equipment induces additional current in the wires. These factors combined result in a significant deviation between the actual current-carrying capacity and the static setting. Existing static matching methods cannot correct this deviation in real time, leading to delayed fuse blowing when the actual current exceeds the fuse's rated value, or accidental fuse blown affecting equipment operation. In severe cases, this can cause wire overheating and fire, posing a significant safety hazard during vehicle operation.

[0003] Based on the above problems, there is an urgent need for a fuse and wire matching test scheme that can dynamically adapt to the coupling effects of multiple factors. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and to propose a method for testing the matching degree of fuses and wires in automotive wiring harnesses, comprising the following steps:

[0005] S1: Collect the physical parameters of the conductor and the rated parameters of the fuse, and preset the safety matching threshold;

[0006] S2: Synchronously collect conductor aging parameters, environmental parameters, load current parameters, contact resistance parameters, vibration parameters, and load frequency parameters;

[0007] S3: Calculate the aging attenuation factor based on the conductor aging parameters, calculate the temperature correction coefficient based on the temperature parameter in the environmental parameters, calculate the electromagnetic induction additional current based on the electromagnetic induction intensity parameter in the environmental parameters, calculate the vibration influence factor based on the vibration parameters, calculate the skin effect correction term based on the load frequency parameter, calculate the multi-load coordination factor based on the proportion of each load current in the load current parameter, and calculate the contact resistance correction term based on the contact resistance parameter.

[0008] S4: Based on the conductor's rated current carrying capacity at room temperature, the aging attenuation factor, the temperature correction coefficient, and the electromagnetic induction additional current in the conductor's physical parameters, the conductor's dynamic current carrying capacity is corrected to obtain the conductor's dynamic current carrying capacity.

[0009] S5: Based on the actual operating current of the conductor, the dynamic current carrying capacity of the conductor, the vibration influence factor, and the skin effect correction term in the load current parameters, the matching degree risk warning index is calculated.

[0010] S6: Based on the matching degree risk warning index, the safety matching threshold, the multi-load coordination factor and the contact resistance correction term, calculate the adaptive matching adjustment coefficient, and perform the matching state adjustment operation according to the adaptive matching adjustment coefficient.

[0011] Preferably, in step S1, the physical parameters of the conductor include the conductor cross-sectional area, initial resistivity, length, and skin depth; the rated parameters of the fuse include the rated fusing threshold; and the safety matching threshold is a dimensionless parameter used to define the safety boundary of the matching state.

[0012] More preferably, in step S2, the conductor aging parameters include conductor aging time and conductor surface roughness; the environmental parameters include ambient temperature and electromagnetic induction intensity; the load current parameters include multi-load operating current, instantaneous inrush current, the proportion of each load current, and the rated load current; the contact resistance parameter is the contact resistance between the fuse and the conductor connector; the vibration parameter is vibration acceleration; and the load frequency parameter is the load angular frequency.

[0013] Further preferably, in step S3, the aging attenuation factor is a dimensionless parameter derived from the aging time and surface roughness of the conductor. The derivation logic is that the longer the aging time and the greater the surface roughness, the smaller the aging attenuation factor value; the temperature correction coefficient is a dimensionless parameter derived from the temperature characteristics of the conductor resistivity. The derivation logic is that the higher the ambient temperature, the smaller the temperature correction coefficient value; the electromagnetic induction additional current is a current parameter derived from the law of electromagnetic induction. The derivation logic is that the greater the electromagnetic induction intensity, the greater the electromagnetic induction additional current value; the vibration influence factor is... The dimensionless parameter derived from vibration acceleration has the following derivation logic: the greater the vibration acceleration, the larger the value of the vibration influence factor; the skin effect correction term has the following derivation logic: the dimensionless parameter derived from the load angular frequency has the following derivation logic: the higher the load angular frequency, the larger the value of the skin effect correction term; the multi-load coordination factor has the following derivation logic: the dimensionless parameter derived from the weighted summation of the current proportions of each load, and the weighting coefficient is positively correlated with the rated power of each load; the contact resistance correction term has the following derivation logic: the dimensionless parameter derived from the contact resistance between the fuse and the wire connector has the following derivation logic: the greater the contact resistance, the larger the value of the contact resistance correction term.

[0014] More preferably, in step S4, the dynamic current-carrying capacity of the conductor is calculated using the aging-temperature-electromagnetic coupling corrected current-carrying formula. The aging-temperature-electromagnetic coupling corrected current-carrying formula is constructed based on the correlation between the conductor's rated current-carrying capacity, aging attenuation factor, temperature correction coefficient, and electromagnetic induction additional current, and is used to reflect the comprehensive influence of aging, temperature, and electromagnetic factors on the conductor's current-carrying capacity.

[0015] More preferably, in step S5, the matching degree risk warning index is calculated by a multi-factor coupled matching risk index formula. The multi-factor coupled matching risk index formula is constructed based on the correlation between the actual working current of the conductor, the dynamic current carrying capacity of the conductor, the vibration influence factor and the skin effect correction term, and is used to quantify the matching risk degree between the fuse and the conductor.

[0016] More preferably, in step S6, the adaptive matching adjustment coefficient is calculated by the multi-load collaborative matching adjustment coefficient formula. The multi-load collaborative matching adjustment coefficient formula is constructed based on the correlation between the matching degree risk warning index, the safety matching threshold, the multi-load collaborative factor and the contact resistance correction term, and is used to determine the adjustment range of the matching state.

[0017] Further preferably, step S7 is included: repeating steps S2 to S6 to achieve dynamic cyclic monitoring of the matching degree of the fuse and the conductor. The cycle of the cyclic monitoring is determined by the frequency of change of the instantaneous impact current in the load current parameters. During each cyclic monitoring process, various real-time parameters are re-acquired and the corresponding aging attenuation factor, temperature correction coefficient, electromagnetic induction additional current, vibration influence factor, skin effect correction term, multi-load coordination factor, contact resistance correction term, conductor dynamic current carrying capacity, matching degree risk warning index and adaptive matching adjustment coefficient are updated.

[0018] A testing system for the matching degree of fuses and wires in automotive wiring harnesses includes: a wire physical parameter acquisition module for acquiring wire cross-sectional area, initial resistivity, length, and skin depth; a fuse parameter acquisition module for acquiring the rated fusing threshold of the fuse; a preset module for presetting safety matching thresholds; an aging parameter acquisition module for acquiring wire aging time and wire surface roughness; an environmental parameter acquisition module for acquiring ambient temperature and electromagnetic induction intensity; a load current acquisition module for acquiring multi-load operating current, instantaneous inrush current, current percentage of each load, and rated load current; a contact resistance acquisition module for acquiring the contact resistance between the fuse and the wire connector; a vibration parameter acquisition module for acquiring vibration acceleration; a load frequency acquisition module for acquiring the load angular frequency; and a correction factor calculation module for calculating an aging attenuation factor based on wire aging time and wire surface roughness, a temperature correction coefficient based on ambient temperature, electromagnetic induction additional current based on electromagnetic induction intensity, a vibration influence factor based on vibration acceleration, a skin effect correction term based on load angular frequency, a multi-load synergy factor based on current percentage of each load, and a contact resistance calculation module based on the contact resistance between the fuse and the wire connector. The system comprises the following modules: a resistance correction term; a dynamic current-carrying calculation module, used to calculate the dynamic current-carrying capacity of the conductor based on the conductor's rated current-carrying capacity at room temperature, aging attenuation factor, temperature correction coefficient, and electromagnetic induction additional current, using an aging-temperature-electromagnetic coupling correction formula; a risk index assessment module, used to calculate the matching degree risk warning index based on the conductor's actual operating current, dynamic current-carrying capacity, vibration influence factor, and skin effect correction term, using a multi-factor coupling matching risk index formula; an adaptive adjustment module, used to calculate the adaptive matching adjustment coefficient based on the matching degree risk warning index, safety matching threshold, multi-load coordination factor, and contact resistance correction term, using a multi-load coordinated matching adjustment coefficient formula, and to perform matching status adjustment operations according to the adaptive matching adjustment coefficient; and a cyclic monitoring module, used to control the aging parameter acquisition module, environmental parameter acquisition module, load current acquisition module, contact resistance acquisition module, vibration parameter acquisition module, load frequency acquisition module, correction factor calculation module, dynamic current-carrying calculation module, risk index assessment module, and adaptive adjustment module to repeatedly perform data acquisition, calculation, and adjustment operations to achieve dynamic cyclic monitoring. The cyclic monitoring module is also used to set the cyclic monitoring cycle according to the frequency of instantaneous impact current changes.

[0019] Further preferably, it also includes a result output module, which is used to receive the matching status adjustment result output by the adaptive adjustment module and the dynamic monitoring data output by the cyclic monitoring module, and display the matching degree level and adjustment suggestions in text form. The matching degree level is divided based on the matching degree risk warning index and the adaptive matching adjustment coefficient, and the adjustment suggestions are generated based on the adjustment operation corresponding to the adaptive matching adjustment coefficient.

[0020] Technical effects: This invention utilizes innovative techniques such as aging-temperature-electromagnetic coupling correction of current carrying capacity, multi-factor risk quantification, and multi-load coordinated adjustment to dynamically correct the current carrying capacity and matching parameters of conductors. This precisely solves the core problem that existing static matching cannot adapt to the influence of multi-factor coupling, ensuring that the matching status of automotive wiring harnesses is controllable in real time and improving safety and stability in use. Attached Figure Description

[0021] Figure 1 This is a flowchart of a test method for the matching degree of fuses and wires for automotive wiring harnesses according to this application;

[0022] Figure 2 This is a connection block diagram of a test system for the matching degree of fuses and wires for automotive wiring harnesses according to this application. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0024] Existing technologies use a static matching method, which does not consider the dynamic impact of multiple factors such as aging temperature and electromagnetic coupling on the matching state of fuses and wires, leading to the risk of mismatch.

[0025] Based on this, please refer to Figure 1-2 This embodiment provides a method for testing the matching degree of fuses and wires used in automotive wiring harnesses, including the following steps:

[0026] S1, collect the physical parameters of the conductor and the rated parameters of the fuse, and preset the safety matching threshold;

[0027] The core of S1 implementation is to establish a basic benchmark system for the entire test plan. The collection of conductor physical parameters needs to cover the core inherent properties that affect the conductor's current-carrying capacity, while the fuse rated parameters focus on the core protection benchmark for matching. The preset safety matching threshold needs to be determined by combining the typical operating conditions of automotive wiring harnesses and statistically analyzing a large amount of safe operating data of similar wiring harnesses to ensure that it can accurately define the safety boundary of the matching state. S2 synchronously collects conductor aging parameters, environmental parameters, load current parameters, contact resistance parameters, vibration parameters, and load frequency parameters.

[0028] The key to implementing S2 lies in synchronization and comprehensiveness. Synchronous acquisition can avoid operating condition deviations caused by time differences in the acquisition of different parameters. It is necessary to achieve parallel acquisition of various parameters through multi-channel data acquisition equipment, fully cover dynamic factors affecting the matching state, and ensure the integrity and timeliness of the data required for subsequent calculations.

[0029] S3, calculate the aging attenuation factor based on conductor aging parameters, calculate the temperature correction coefficient based on the temperature parameter in the environmental parameters, calculate the electromagnetic induction additional current based on the electromagnetic induction intensity parameter in the environmental parameters, calculate the vibration influence factor based on the vibration parameters, calculate the skin effect correction term based on the load frequency parameter, calculate the multi-load coordination factor based on the proportion of each load current in the load current parameter, and calculate the contact resistance correction term based on the contact resistance parameter.

[0030] S3 is the core step in achieving multi-factor quantification. The calculation of each correction factor and parameter must strictly follow the corresponding physical laws and engineering principles to ensure that the quantification results can accurately reflect the degree of influence of each factor on the matching state.

[0031] S4, based on the conductor's rated current carrying capacity at room temperature, aging attenuation factor, temperature correction coefficient and electromagnetic induction additional current in the conductor's physical parameters, the dynamic current carrying capacity of the conductor is corrected to obtain the conductor's dynamic current carrying capacity.

[0032] S4 overcomes the limitations of traditional static current-carrying settings by using multi-factor coupling correction, enabling the obtained dynamic current-carrying capacity of the conductor to truly reflect the conductor's carrying capacity under actual working conditions.

[0033] S5. Based on the actual working current of the conductor, the dynamic current carrying capacity of the conductor, the vibration influence factor and the skin effect correction term in the load current parameters, the matching degree risk warning index is calculated.

[0034] S5 enables quantitative assessment of matching risks by combining actual current with dynamic current carrying capacity and introducing the effects of vibration and skin effect, making the risk assessment results more consistent with actual operating conditions.

[0035] S6 calculates the adaptive matching adjustment coefficient based on the matching degree risk warning index, safety matching threshold, multi-load coordination factor and contact resistance correction term, and performs matching status adjustment operation according to the adaptive matching adjustment coefficient; S6 completes the closed loop of dynamic matching, and accurately controls the adjustment range through the adaptive adjustment coefficient to ensure that the matching status can adapt to changes in working conditions in real time.

[0036] The core of this technical solution lies in constructing a closed-loop logic encompassing parameter acquisition, factor calculation, dynamic correction, risk assessment, and adaptive adjustment. All technical features are essential for solving the multi-factor coupling and mismatch problem; the absence of any one step prevents the formation of a complete dynamic matching scheme. Step S1 provides a foundational benchmark for subsequent calculations; its absence leaves no clear basis for calculation. Step S2 ensures comprehensive capture of multi-factor data; missing any parameter prevents the quantification of its corresponding influencing factors, leading to matching deviations. Step S3 quantifies and transforms multiple factors; its absence prevents the conversion of physical parameters into usable factors for calculation, hindering subsequent correction and assessment. Step S4 corrects the dynamic current-carrying capacity of the conductor; its absence relies on static current-carrying settings, failing to adapt to changes in operating conditions. Step S5 quantifies matching risks; its absence makes it impossible to determine the safety of the matching state. Step S6 executes adaptive adjustment; its absence prevents effective risk management, leaving the mismatch problem unresolved.

[0037] The dynamic current-carrying capacity of a conductor is calculated using an aging-temperature-electromagnetic coupling corrected current-carrying formula, which is:

[0038] .

[0039] in, It represents the dynamic current-carrying capacity of a conductor, measured in amperes. It reflects the conductor's actual current-carrying capacity under real-world operating conditions and is a core fundamental parameter for subsequent risk assessment and matching adjustments. The rated current carrying capacity of a conductor at room temperature is expressed in amperes. It is a benchmark current carrying capacity value derived from traditional current carrying capacity calculation formulas based on physical parameters such as conductor cross-sectional area and initial resistivity, providing an initial reference for dynamic correction. This represents the aging degradation factor, which is dimensionless. Its design is based on the changes in physical properties of the conductor during the aging process. After long-term use, insulation wear and conductor oxidation lead to increased surface roughness, which in turn increases resistivity and decreases current-carrying capacity. Therefore, this factor is constructed using two parameters: conductor aging time and surface roughness. The longer the aging time and the greater the surface roughness... The smaller the value, the more quantified the impact of aging on current carrying capacity, thus compensating for the shortcomings of existing technologies that ignore aging factors. This represents a dimensionless temperature correction factor, derived from the temperature-sensitive characteristic of conductor resistivity. As conductor resistivity increases with temperature, its current-carrying capacity decreases. This factor is constructed using the linear relationship between ambient temperature and resistivity; the higher the ambient temperature, the lower the resistivity. The smaller the value, the more accurately it reflects the dynamic impact of temperature on the current-carrying capacity of the conductor, solving the problem that traditional static matching does not consider temperature fluctuations. This represents the additional electromagnetic induction current, measured in amperes. Its derivation is based on the law of electromagnetic induction. When equipment such as vehicle-mounted radar motors operate, they generate changing magnetic fields. Conductors placed in these fields will induce an additional current, which is superimposed on the load's operating current, increasing the total current actually carried by the conductor. Therefore, this additional current is calculated using parameters such as electromagnetic induction intensity and conductor length, and then subtracted from the corrected current-carrying capacity to ensure... It can accurately reflect the effective current that a conductor can withstand, thus solving the problem of actual current deviation caused by electromagnetic interference.

[0040] The logical derivation of this formula is based on fundamental physical theory. First, according to Joule's law, the current-carrying capacity of a conductor is inversely proportional to its resistivity. Since aging and temperature both affect resistivity, therefore... and right Multiplication correction is performed to reflect the attenuation effect of resistivity changes on current-carrying capacity; secondly, according to the law of electromagnetic induction, electromagnetic interference will generate additional current, which will increase the actual current load on the conductor. Therefore, subtraction is used to correct this. This is subtracted from the corrected current-carrying capacity to reflect the impact of the additional current on the current-carrying capacity. The formula is implemented by acquiring data from each acquisition module. Parameters such as conductor aging time, surface roughness, ambient temperature, and electromagnetic induction intensity are substituted into the preset values. , Computational models and After obtaining the numerical values ​​of each factor from the calculation model, the result can be calculated by substituting them into the formula. Its innovation lies in breaking through the limitations of traditional single-parameter correction, integrating the three coupled influencing factors of aging temperature and electromagnetic fields into the same formula, realizing the coordinated correction of multiple factors, making the calculation of conductor current carrying capacity more in line with actual working conditions, and solving the core problem that the static current carrying capacity setting of existing technology cannot adapt to the dynamic changes of multiple factors.

[0041] The matching risk warning index is calculated using a multi-factor coupled matching risk index formula, which is as follows: ;

[0042] in, The matching degree risk warning index is dimensionless and presented as a percentage. It intuitively reflects the degree of matching risk between the fuse and the wire, making it easier to determine whether the matching status is safe. Representing the actual operating current of the conductor, measured in amperes, it is the real current value of the conductor during load operation, monitored in real time by the load current acquisition module, and is a core input parameter for risk assessment. It represents the dynamic current-carrying capacity of a conductor, with the dimension of ampere. It forms a ratio with the actual current as the denominator. This ratio directly reflects the matching ratio between the actual current and the conductor's true carrying capacity. The larger the ratio, the closer the actual current is to or exceeds the current-carrying capacity, and the higher the risk. This represents the vibration impact factor, which is dimensionless. Its design is based on the effect of vehicle vibration on the connection between the wire and fuse. Vibration causes fluctuations in the contact pressure of the connector, leading to changes in contact resistance, uneven current distribution, increased local current, and increased risk of mismatch. Therefore, this factor is constructed using vibration acceleration; the greater the vibration acceleration, the more pronounced the fluctuation in contact resistance. The larger the value, the more it quantifies the amplifying effect of vibration on matching risk, thus compensating for the shortcomings of existing technologies that ignore vibration interference. The term representing the skin effect correction is dimensionless and derived based on the distribution characteristics of high-frequency current. When the load angular frequency is high, the current concentrates on the surface of the conductor, leading to a decrease in the effective current-carrying area, an increase in local current density, and a rise in the risk of heating, thus affecting the matching state. Therefore, this correction term is constructed based on the load angular frequency; the higher the load angular frequency, the more pronounced the skin effect. The larger the value, the more it quantifies the impact of the skin effect on matching risk under high-frequency load, thus solving the problem that traditional matching does not consider frequency characteristics.

[0043] The logical derivation of this formula is based on the principle of risk superposition. First, the ratio of actual current to dynamic current-carrying capacity is used as the basic risk indicator, reflecting the basic fit between current load and carrying capacity. Second, considering that vibration and skin effect will further amplify the basic risk, a multiplication operation is used to... and This is combined with basic risk indicators to form a comprehensive risk index; finally, the result is converted into a percentage by multiplying by 100%, improving readability and intuitiveness. The formula is implemented by obtaining data through a load current acquisition module. Obtained through the dynamic current carrying capacity calculation module Vibration acceleration is acquired and calculated through the vibration parameter acquisition module. The load angular frequency is obtained and calculated through the load frequency acquisition module. Substituting the parameters into the formula will yield the result. Its innovation lies in breaking through the limitations of traditional single-dimensional risk assessment, integrating three factors—current adaptation ratio, vibration interference, and skin effect—into a single formula, achieving synergistic quantification of multi-dimensional risks, making the risk assessment results more comprehensive and accurate, and solving the problem of incomplete risk assessment in existing technologies.

[0044] The adaptive matching adjustment coefficient is calculated using the multi-load collaborative matching adjustment coefficient formula, which is: ;

[0045] in, This represents the adaptive matching adjustment coefficient, which is dimensionless and ranges from 0 to 1. It directly determines the adjustment range of the matching state. The closer the value is to 1, the safer the matching status is, and no major adjustments are needed. The smaller the value, the higher the matching risk, requiring a more significant adjustment. The matching degree risk warning index is dimensionless and is the core result of risk assessment, directly reflecting the current level of matching risk. Representing the safety matching threshold, it is dimensionless and serves as a benchmark value for defining whether a matching state is safe or not. It is preset through a large amount of experimental data and engineering experience to ensure that it can accurately divide the safe area and the risk area. This represents a multi-load coordination factor, which is dimensionless. Its design is based on the current superposition effect during multi-load operation. Automotive wiring harnesses typically connect multiple loads, and the different start-stop times of each load can lead to current superposition, causing instantaneous peaks in the actual current of the conductors and increasing the risk of mismatch. Therefore, this factor is constructed by weighted summation of the current proportions of each load. The weighting coefficient is positively correlated with the rated power of the load. The larger the rated power of the load, the greater its contribution to current superposition. This quantifies the impact of multi-load coordinated operation on the matching state and solves the defect of existing technologies that ignore multi-load superposition interference. This represents a dimensionless correction term for contact resistance, derived from the contact resistance characteristics of the conductor and fuse connection. Higher contact resistance leads to greater voltage drop and heat generation during current flow. Increased local temperature accelerates conductor aging and fuse performance degradation, thus affecting the matching condition. Therefore, this correction term is constructed based on contact resistance; the higher the contact resistance, the more significant the negative impact on the matching condition. The larger the value, the more quantified the impact of contact resistance on matching adjustment, thus compensating for the deficiency of existing technology in ignoring contact resistance.

[0046] The logical derivation of this formula is based on the correlation between risk deviation and adjustment magnitude. First, the risk warning index is calculated. With safety threshold The difference reflects the degree to which the risk deviates from the safety benchmark. A positive difference indicates the presence of risk, and a larger difference indicates a higher risk. Secondly, considering that multi-load coordination and contact resistance can amplify the impact of risk deviation, a multiplication operation is used to... and By combining this result with the risk deviation, a quantitative basis for the adjustment magnitude is obtained; finally, by subtracting this combined result from 1, the adaptive adjustment coefficient is obtained. This establishes an inverse relationship between risk deviation and adjustment magnitude; the higher the risk, the larger the adjustment. The formula is implemented by obtaining the risk index assessment module. Retrieve preset The load current acquisition module obtains the proportion of each load current and calculates it. The contact resistance is obtained and calculated through the contact resistance acquisition module. Substituting the parameters into the formula will yield the result. And then according to The numerical value triggers corresponding adjustment operations, such as calibrating the fuse blowing threshold or limiting load power. Its innovation lies in breaking through the limitations of traditional fixed adjustment logic, integrating three factors—risk deviation, multi-load coordination, and contact resistance—into a single formula. This achieves adaptive quantification of the adjustment range, making the matching adjustment more precise and closely aligned with actual operating conditions, thus solving the problem of rigid adjustment methods in existing technologies.

[0047] Existing technologies do not clearly define the specific composition of conductor physical parameters and fuse rated parameters, resulting in incomplete basic data collection.

[0048] Based on this, in step S1, the physical parameters of the conductor include the conductor cross-sectional area, initial resistivity, length, and skin depth; the rated parameters of the fuse include the rated fusing threshold; and the safety matching threshold is a dimensionless parameter used to define the safety boundary of the matching state.

[0049] The selection of conductor physical parameters is a core factor influencing the conductor's current-carrying capacity. The conductor's cross-sectional area directly determines its current-carrying area, while initial resistivity is an inherent property of the conductor material. Both together determine the conductor's base resistance and rated current-carrying capacity at room temperature. Length affects the conductor's total resistance; higher resistance leads to more significant heat generation, indirectly impacting current-carrying capacity. Skin depth is related to current-carrying characteristics under high-frequency loads, providing fundamental data for subsequent skin effect correction. The fuse's rated fusing threshold is a core benchmark parameter for matching, directly determining the fuse's protection triggering conditions and serving as a key basis for judging the rationality of matching. The safety matching threshold, as a risk definition benchmark, is dimensionless to ensure the uniformity and comparability of risk assessments, avoiding judgment biases caused by dimensional differences. The explicit collection of these parameters provides comprehensive and accurate fundamental data support for subsequent dynamic matching calculations, avoiding matching biases caused by missing fundamental data and ensuring the smooth implementation of the entire technical solution's calculation logic.

[0050] Existing technologies do not systematically define the types of parameters collected in real time, resulting in the inability to fully capture the influence of multiple factors.

[0051] Based on this, in step S2, the conductor aging parameters include conductor aging time and conductor surface roughness; the environmental parameters include ambient temperature and electromagnetic induction intensity; the load current parameters include multi-load operating current, instantaneous inrush current, the proportion of each load current, and the load rated current; the contact resistance parameter is the contact resistance between the fuse and the conductor connector; the vibration parameter is vibration acceleration; and the load frequency parameter is the load angular frequency.

[0052] Conductor aging parameters reflect the impact of long-term use on conductor performance. Aging time directly relates to the degree of conductor aging, while surface roughness reflects the wear state of the conductor and insulation layer. Both factors jointly determine the value of the aging attenuation factor. Environmental parameters capture the interference of the external environment on the matching state. Ambient temperature affects conductor resistivity, and electromagnetic induction intensity determines the magnitude of the electromagnetic induction additional current. Load current parameters reflect the dynamic changes in load operation. Multi-load operating current is the current value during normal operation, while instantaneous inrush current is the peak current during load start-up and shutdown. The proportion of each load current is used to calculate the multi-load synergy factor, and the rated load current provides the basis for the weighting coefficient of the synergy factor. Contact resistance parameters reflect the connection state of the joint, directly affecting current transmission and local heating, and are the basis for calculating the contact resistance correction term. Vibration parameters quantify the interference of mechanical vibration on the connection parts, providing data support for the vibration influence factor. Load frequency parameters relate to the strength of the skin effect and are the basis for calculating the skin effect correction term. The clear definition of each parameter ensures that the influence of multiple factors can be accurately captured, providing comprehensive data support for subsequent factor calculations and dynamic corrections, enabling the technical solution to cover the main influencing factors in actual working conditions.

[0053] The existing technology does not clearly define the derivation logic of various correction factors, resulting in inaccurate quantification of the influence of multiple factors.

[0054] Based on this, in step S3, the aging attenuation factor is a dimensionless parameter derived from the aging time and surface roughness of the conductor. The derivation logic is that the longer the aging time and the greater the surface roughness, the smaller the aging attenuation factor value; the temperature correction coefficient is a dimensionless parameter derived from the temperature characteristics of the conductor resistivity. The derivation logic is that the higher the ambient temperature, the smaller the temperature correction coefficient value; the electromagnetic induction additional current is a current parameter derived from the law of electromagnetic induction. The derivation logic is that the greater the electromagnetic induction intensity, the greater the electromagnetic induction additional current value; the vibration influence factor is based on... The dimensionless parameter derived from vibration acceleration follows the logic that the greater the vibration acceleration, the larger the value of the vibration influence factor. The skin effect correction term is a dimensionless parameter derived from the load angular frequency, with the logic that the higher the load angular frequency, the larger the value of the skin effect correction term. The multi-load synergy factor is a dimensionless parameter derived from the weighted summation of the current proportions of each load, with the weighting coefficient positively correlated with the rated power of each load. The contact resistance correction term is a dimensionless parameter derived from the contact resistance between the fuse and the wire connector, with the logic that the greater the contact resistance, the larger the value of the contact resistance correction term. Each factor is designed based on its corresponding physical characteristics or engineering principles to ensure the accuracy of the quantification results. The aging degradation factor and temperature correction coefficient are based on the change law of conductor resistivity. An association model between aging time, surface roughness, ambient temperature, and resistivity is established using experimental data to derive the correspondence between factors and parameters. The electromagnetic induction additional current is calculated based on the law of electromagnetic induction, using parameters such as electromagnetic induction intensity, conductor length, and conductor speed to ensure that the calculation of the additional current conforms to the physical laws of electromagnetic induction. The vibration impact factor, based on the contact resistance fluctuation characteristics, establishes a correlation model between vibration acceleration and contact resistance fluctuation amplitude by experimentally measuring contact resistance changes under different vibration accelerations, and then transforms this into a correspondence between the vibration impact factor and vibration acceleration. The skin effect correction term, based on the high-frequency current distribution law, derives its correspondence with the load angular frequency through the theoretical relationship between load angular frequency and skin depth. The multi-load synergy factor, based on the correlation between load power and current, uses the load's rated power as a weighting coefficient to weight and sum the current proportions of each load, quantifying the impact of multiple loads superimposed on the current. The contact resistance correction term, based on the principle of local heating, derives its correspondence with contact resistance through a correlation model between contact resistance and local heat generation. These derivation logics ensure that various correction factors can accurately quantify the impact of corresponding factors, providing a reliable calculation basis for subsequent dynamic corrections and risk assessments.

[0055] The lack of a clear design for a cyclic monitoring mechanism in existing technologies leads to insufficient sustainability of dynamic matching.

[0056] Based on this, step S7 is also included: repeating steps S2 to S6 to achieve dynamic cyclic monitoring of the fuse and conductor matching degree. The cyclic monitoring period is determined by the frequency of instantaneous inrush current change in the load current parameters. During each cyclic monitoring process, various real-time parameters are re-acquired and the corresponding aging attenuation factor, temperature correction coefficient, electromagnetic induction additional current, vibration influence factor, skin effect correction term, multi-load coordination factor, contact resistance correction term, conductor dynamic current carrying capacity, matching degree risk warning index, and adaptive matching adjustment coefficient are updated. The core of the cyclic monitoring mechanism is to track changes in operating conditions in real time to ensure that the matching state can continuously adapt to dynamic operating conditions. The monitoring period is set using adaptive logic, adjusted according to the frequency of instantaneous inrush current change. When the frequency of instantaneous inrush current change is high, it indicates that the load operating state is unstable and the operating conditions change frequently, requiring a shorter monitoring period to quickly capture changes in the matching state; when the frequency of instantaneous inrush current change is low, it indicates that the load operating state is relatively stable, and the monitoring period can be appropriately extended to reduce system energy consumption. During each cycle, each acquisition module re-acquires real-time parameters to ensure the data reflects the current operating conditions. Each calculation module recalculates various correction factors, conductor dynamic current-carrying capacity, matching degree risk warning index, and adaptive matching adjustment coefficient based on the newly acquired parameters, ensuring the real-time nature and accuracy of the calculation results. This cyclical monitoring mechanism enables the technical solution to overcome the limitations of traditional single-test testing, achieving continuous monitoring and dynamic adjustment of the matching state. This ensures timely response when operating conditions change, maintaining the safety and stability of the matching state and addressing the shortcomings of existing static matching methods that cannot adapt to dynamic changes in operating conditions.

[0057] The lack of a system architecture corresponding to the dynamic matching method in the existing technology makes it impossible to effectively implement the method.

[0058] Based on this, this embodiment provides a testing system for the matching degree of fuses and wires in automotive wiring harnesses, including: a wire physical parameter acquisition module for acquiring wire cross-sectional area, initial resistivity, length, and skin depth; a fuse parameter acquisition module for acquiring the rated fusing threshold of the fuse; a preset module for presetting a safety matching threshold; an aging parameter acquisition module for acquiring wire aging time and wire surface roughness; an environmental parameter acquisition module for acquiring ambient temperature and electromagnetic induction intensity; a load current acquisition module for acquiring multi-load operating current, instantaneous inrush current, the proportion of each load current, and the rated load current; a contact resistance acquisition module for acquiring the contact resistance between the fuse and the wire connector; a vibration parameter acquisition module for acquiring vibration acceleration; a load frequency acquisition module for acquiring the load angular frequency; and a correction factor calculation module for calculating an aging attenuation factor based on wire aging time and wire surface roughness, a temperature correction coefficient based on ambient temperature, an electromagnetic induction additional current based on electromagnetic induction intensity, a vibration influence factor based on vibration acceleration, a skin effect correction term based on load angular frequency, a multi-load synergy factor based on the proportion of each load current, and a correction factor based on the contact resistance between the fuse and the wire connector. The system includes: a contact resistance correction term calculation module; a dynamic current-carrying calculation module, used to calculate the dynamic current-carrying capacity of the conductor based on the conductor's rated current-carrying capacity at room temperature, aging attenuation factor, temperature correction coefficient, and electromagnetic induction additional current, using an aging-temperature-electromagnetic coupling correction formula; a risk index assessment module, used to calculate the matching degree risk warning index based on the conductor's actual operating current, dynamic current-carrying capacity, vibration influence factor, and skin effect correction term, using a multi-factor coupling matching risk index formula; an adaptive adjustment module, used to calculate the adaptive matching adjustment coefficient based on the matching degree risk warning index, safety matching threshold, multi-load coordination factor, and contact resistance correction term, using a multi-load coordinated matching adjustment coefficient formula, and to perform matching status adjustment operations based on the adaptive matching adjustment coefficient; and a cyclic monitoring module, used to control the aging parameter acquisition module, environmental parameter acquisition module, load current acquisition module, contact resistance acquisition module, vibration parameter acquisition module, load frequency acquisition module, correction factor calculation module, dynamic current-carrying calculation module, risk index assessment module, and adaptive adjustment module to repeatedly perform data acquisition, calculation, and adjustment operations to achieve dynamic cyclic monitoring. The cyclic monitoring module is also used to set the cyclic monitoring cycle based on the frequency of instantaneous impact current changes. The system architecture and testing methods are perfectly aligned, with each module performing its specific function while working collaboratively to ensure the effective implementation of the dynamic matching method. The data acquisition module is responsible for the accurate collection of various parameters, providing data input for the entire system; the calculation module is responsible for converting the collected parameters into quantitative indicators that can be used for evaluation and adjustment, serving as the core processing unit of the system; the adjustment module is responsible for executing specific adjustment operations based on the calculation results, optimizing the matching state; and the cyclic monitoring module is responsible for controlling the coordinated operation of all modules, ensuring that the system can continuously adapt to changes in operating conditions.The system architecture design achieves deep integration of hardware and software. The acquisition module provides hardware support, while the calculation and adjustment module implements core functions through software algorithms. The collaborative work of each module enables the technical solution to be implemented from the theoretical level to practical application, solving the problem of the disconnect between methods and systems in existing technologies.

[0059] Existing technologies lack an intuitive output mechanism for matching results, making it impossible for users to obtain matching status and adjustment suggestions in a timely manner.

[0060] Based on this, a result output module is also included. This module receives the matching status adjustment results output by the adaptive adjustment module and the dynamic monitoring data output by the cyclic monitoring module, and displays the matching degree level and adjustment suggestions in text form. The matching degree level is based on the matching degree risk warning index and the adaptive matching adjustment coefficient. The adjustment suggestions are generated based on the adjustment operations corresponding to the adaptive matching adjustment coefficient. The core function of the result output module is to transform the system's internal calculation results and adjustment operations into user-understandable information, improving the system's practicality and ease of use. The matching degree level is divided based on a preset threshold range. By comparing the matching degree risk warning index and the adaptive matching adjustment coefficient with the preset threshold, different matching state levels are defined, allowing users to quickly determine the safety of the current matching state. The adjustment suggestions are generated based on the adjustment operations corresponding to the adaptive matching adjustment coefficient. For different matching degree levels and adjustment coefficient values, specific executable operation guidelines are generated, such as maintaining the current matching state, calibrating the fuse blowing threshold, limiting load power, or replacing wires. The result output module displays information in text form, ensuring that users can clearly and intuitively obtain relevant content and take corresponding measures in a timely manner. This solves the problems of unintuitive matching results and slow user response in existing technologies, enhancing the practical application value of the system.

[0061] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for testing the matching degree of fuses and wires for automotive wiring harnesses, characterized in that, Includes the following steps: S1: Collect the physical parameters of the conductor and the rated parameters of the fuse, and preset the safety matching threshold; S2: Synchronously collect conductor aging parameters, environmental parameters, load current parameters, contact resistance parameters, vibration parameters, and load frequency parameters; S3: Calculate the aging attenuation factor based on the conductor aging parameters, calculate the temperature correction coefficient based on the temperature parameter in the environmental parameters, calculate the electromagnetic induction additional current based on the electromagnetic induction intensity parameter in the environmental parameters, calculate the vibration influence factor based on the vibration parameters, calculate the skin effect correction term based on the load frequency parameter, calculate the multi-load coordination factor based on the proportion of each load current in the load current parameter, and calculate the contact resistance correction term based on the contact resistance parameter. S4: Based on the conductor's rated current carrying capacity at room temperature, the aging attenuation factor, the temperature correction coefficient, and the electromagnetic induction additional current in the conductor's physical parameters, the conductor's dynamic current carrying capacity is corrected to obtain the conductor's dynamic current carrying capacity. S5: Based on the actual operating current of the conductor, the dynamic current carrying capacity of the conductor, the vibration influence factor, and the skin effect correction term in the load current parameters, the matching degree risk warning index is calculated. S6: Based on the matching degree risk warning index, the safety matching threshold, the multi-load coordination factor and the contact resistance correction term, calculate the adaptive matching adjustment coefficient, and perform the matching state adjustment operation according to the adaptive matching adjustment coefficient.

2. The method for testing the matching degree of fuses and wires for automotive wiring harnesses according to claim 1, characterized in that, In step S1, the physical parameters of the conductor include the conductor cross-sectional area, initial resistivity, length, and skin depth; the rated parameters of the fuse include the rated fusing threshold; and the safety matching threshold is a dimensionless parameter used to define the safety boundary of the matching state.

3. The method for testing the matching degree of fuses and wires for automotive wiring harnesses according to claim 1, characterized in that, In step S2, the conductor aging parameters include conductor aging time and conductor surface roughness; the environmental parameters include ambient temperature and electromagnetic induction intensity; the load current parameters include multi-load operating current, instantaneous inrush current, the proportion of each load current, and the rated load current; the contact resistance parameter is the contact resistance between the fuse and the conductor connector; the vibration parameter is vibration acceleration; and the load frequency parameter is the load angular frequency.

4. The method for testing the matching degree of fuses and wires for automotive wiring harnesses according to claim 1, characterized in that, In step S3, the aging attenuation factor is a dimensionless parameter derived from the aging time and surface roughness of the conductor. The derivation logic is that the longer the aging time of the conductor and the greater the surface roughness, the smaller the value of the aging attenuation factor. The temperature correction coefficient is a dimensionless parameter derived from the temperature characteristics of conductor resistivity. The derivation logic is that the higher the ambient temperature, the smaller the value of the temperature correction coefficient. The electromagnetic induction additional current is a current parameter derived from the law of electromagnetic induction. The derivation logic is that the greater the electromagnetic induction intensity, the larger the value of the electromagnetic induction additional current. The vibration influence factor is a dimensionless parameter derived from vibration acceleration. The derivation logic is that the greater the vibration acceleration, the larger the value of the vibration influence factor. The skin effect correction term is a dimensionless parameter derived from the load angular frequency. The derivation logic is that the higher the load angular frequency, the larger the value of the skin effect correction term. The multi-load coordination factor is a dimensionless parameter derived from the weighted summation of the current proportions of each load. The weighting coefficient is positively correlated with the rated power of each load. The contact resistance correction term is a dimensionless parameter derived from the contact resistance between the fuse and the conductor joint. The derivation logic is that the greater the contact resistance, the larger the value of the contact resistance correction term.

5. The method for testing the matching degree of fuses and wires for automotive wiring harnesses according to claim 1, characterized in that, In step S4, the dynamic current-carrying capacity of the conductor is calculated using the aging-temperature-electromagnetic coupling corrected current-carrying formula. This formula is based on the correlation between the conductor's rated current-carrying capacity, aging attenuation factor, temperature correction coefficient, and electromagnetic induction additional current, and is used to reflect the comprehensive influence of aging, temperature, and electromagnetic factors on the conductor's current-carrying capacity.

6. The method for testing the matching degree of fuses and wires for automotive wiring harnesses according to claim 1, characterized in that, In step S5, the matching degree risk warning index is calculated by the multi-factor coupled matching risk index formula. The multi-factor coupled matching risk index formula is constructed based on the correlation between the actual working current of the conductor, the dynamic current carrying capacity of the conductor, the vibration influence factor and the skin effect correction term, and is used to quantify the matching risk degree between the fuse and the conductor.

7. The method for testing the matching degree of fuses and wires for automotive wiring harnesses according to claim 1, characterized in that, In step S6, the adaptive matching adjustment coefficient is calculated using the multi-load collaborative matching adjustment coefficient formula. The multi-load collaborative matching adjustment coefficient formula is constructed based on the correlation between the matching degree risk warning index, the safety matching threshold, the multi-load collaborative factor, and the contact resistance correction term, and is used to determine the adjustment range of the matching state.

8. The method for testing the matching degree of fuses and wires for automotive wiring harnesses according to claim 1, characterized in that, It also includes step S7: repeating steps S2 to S6 to achieve dynamic cyclic monitoring of the matching degree of the fuse and the conductor. The cycle of the cyclic monitoring is determined by the frequency of change of the instantaneous impact current in the load current parameters. During each cyclic monitoring process, various real-time parameters are re-acquired and the corresponding aging attenuation factor, temperature correction coefficient, electromagnetic induction additional current, vibration influence factor, skin effect correction term, multi-load coordination factor, contact resistance correction term, conductor dynamic current carrying capacity, matching degree risk warning index and adaptive matching adjustment coefficient are updated.

9. A testing system for the matching degree of fuses and wires in automotive wiring harnesses, characterized in that, include: The conductor physical parameter acquisition module is used to acquire conductor cross-sectional area, initial resistivity, length, and skin depth. The fuse parameter acquisition module is used to acquire the rated fusing threshold of the fuse; The preset module is used to preset the security matching threshold; The aging parameter acquisition module is used to collect the aging time and surface roughness of the conductor. The environmental parameter acquisition module is used to collect ambient temperature and electromagnetic induction intensity. The load current acquisition module is used to collect the operating current of multiple loads, instantaneous inrush current, current ratio of each load, and rated current of the load. The contact resistance acquisition module is used to acquire the contact resistance between the fuse and the wire connector; Vibration parameter acquisition module, used to acquire vibration acceleration; Load frequency acquisition module, used to acquire the load angular frequency; The correction factor calculation module is used to calculate the aging attenuation factor based on the aging time and surface roughness of the conductor, the temperature correction coefficient based on the ambient temperature, the electromagnetic induction additional current based on the electromagnetic induction intensity, the vibration influence factor based on the vibration acceleration, the skin effect correction term based on the load angular frequency, the multi-load coordination factor based on the current ratio of each load, and the contact resistance correction term based on the contact resistance between the fuse and the conductor joint. The dynamic current carrying capacity calculation module is used to calculate the dynamic current carrying capacity of a conductor based on its rated current carrying capacity at room temperature, aging attenuation factor, temperature correction coefficient, and electromagnetic induction additional current, through an aging-temperature-electromagnetic coupling correction formula. The risk index assessment module is used to calculate the matching degree risk warning index based on the actual working current of the conductor, the dynamic current carrying capacity of the conductor, the vibration influence factor and the skin effect correction term, through a multi-factor coupled matching risk index formula. The adaptive adjustment module is used to calculate the adaptive matching adjustment coefficient based on the matching degree risk warning index, safety matching threshold, multi-load coordination factor, and contact resistance correction term, using the multi-load coordination matching adjustment coefficient formula, and to perform matching state adjustment operations according to the adaptive matching adjustment coefficient. The cyclic monitoring module is used to control the aging parameter acquisition module, environmental parameter acquisition module, load current acquisition module, contact resistance acquisition module, vibration parameter acquisition module, load frequency acquisition module, correction factor calculation module, dynamic current carrying calculation module, risk index assessment module, and adaptive adjustment module to repeatedly perform data acquisition, calculation, and adjustment operations to achieve dynamic cyclic monitoring. The cyclic monitoring module is also used to set the cyclic monitoring cycle according to the frequency of instantaneous impact current change.

10. The testing system for the matching degree of fuses and wires for automotive wiring harnesses according to claim 9, characterized in that, It also includes a result output module, which receives the matching status adjustment results output by the adaptive adjustment module and the dynamic monitoring data output by the cyclic monitoring module, and displays the matching degree level and adjustment suggestions in text form. The matching degree level is divided based on the matching degree risk warning index and the adaptive matching adjustment coefficient, and the adjustment suggestions are generated based on the adjustment operation corresponding to the adaptive matching adjustment coefficient.

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