Wiring harness detection method and system for washing machine

Abstract

The invention relates to the technical field of physical sensors, and provides a wire harness detection method and system for a washing machine, and the method comprises the steps: collecting a current signal and the temperature of a wire harness through an electrical sensor, and obtaining a current signal sequence and a current data set; acquiring a temperature compensation current sequence according to the current data set; obtaining an amplitude jump coefficient of the temperature compensation current according to the temperature compensation current sequence; acquiring a frequency spectrum diversity index of the temperature compensation current according to the temperature compensation current sequence; acquiring noise compensation current according to the spectrum diversity index and the temperature compensation current sequence, acquiring a noise compensation current sequence according to the noise compensation current, acquiring suspected abnormal current according to the value of the noise compensation current, and detecting the wire harness of the washing machine according to the number of the suspected abnormal current and the noise compensation current sequence. The problem that the wire harness detection result is inaccurate is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of physical sensors, and in particular to a wiring harness detection method and system for a washing machine. Background Art

[0002] Washing machines are frequently used household appliances. The quality of the electrical circuits and wiring harnesses of washing machines is directly related to the working performance and safety of washing machines. If a wiring harness failure occurs during the use of the washing machine, the wiring harness failure will cause the washing machine to fail to work properly. In severe cases, the wiring harness failure will also cause accidents such as leakage and fire, bringing safety hazards. In order to ensure the normal operation of the washing machine and the safety of the user, it is very important to test the wiring harness of the washing machine. For manufacturers, wiring harness testing is also a task that must be completed during the production process. By testing the wiring harness of the washing machine, it is possible to promptly detect whether the washing machine has problems such as poor contact, short circuit, open circuit, and line aging, thereby ensuring the normal operation of the wiring harness.

[0003] Usually, the accuracy and reliability of the wiring harness connection can be judged by monitoring the current changes in the wiring harness and potential problems of the wiring harness connection can be discovered in time. However, in the actual detection process, there are current fluctuations in the power supply. At the same time, unreasonable wiring harness length and layout, temperature changes, and noise such as electromagnetic interference from other electrical equipment will also affect the actual value of the current. These influencing factors will affect the detection results of current changes. What's worse, it is difficult to distinguish the current fluctuations caused by the influence of these influencing factors on the current from the current fluctuations caused by poor contact, resulting in inaccurate wiring harness detection results. Summary of the invention

[0004] The present invention provides a wiring harness detection method and system for a washing machine to solve the problem of inaccurate wiring harness detection results. The technical solution adopted is as follows:

[0005] In a first aspect, an embodiment of the present invention provides a wiring harness detection method for a washing machine, the method comprising the following steps:

[0006] Using electrical sensors and temperature sensors to collect current signals and wiring harness temperatures when the washing machine is working, and obtaining current signal sequences and current data groups;

[0007] Obtain the linear term coefficient and the quadratic term coefficient according to the relationship between the current data groups, and then obtain the temperature influence amplitude, obtain the temperature compensation current according to the temperature influence amplitude and the current data group, and obtain the temperature compensation current sequence according to the acquisition time corresponding to the temperature compensation current;

[0008] Obtaining the adjacent temperature compensation current of the temperature compensation current according to the time relationship of the acquisition time corresponding to the temperature compensation current, obtaining the maximum value of the temperature compensation current and the minimum value of the temperature compensation current according to the numerical relationship between the temperature compensation currents included in the temperature compensation current sequence, and obtaining the amplitude jump coefficient of the temperature compensation current according to the adjacent temperature compensation current, the maximum value of the temperature compensation current and the minimum value of the temperature compensation current;

[0009] Obtain a frequency response sequence according to the temperature compensated current sequence, obtain the main frequency and all frequency components of the frequency response sequence, obtain the first frequency component according to the numerical relationship between the main frequency and the energy of all frequency components, obtain the component coefficient of the first frequency component, and obtain the spectrum diversity index of the temperature compensated current according to the amplitude jump coefficient of the temperature compensated current, the component coefficient and the first frequency component corresponding to the adjacent temperature compensated current of the temperature compensated current;

[0010] The noise compensation current is obtained according to the spectrum diversity index and the temperature compensation current sequence, the noise compensation current sequence is obtained according to the noise compensation current, the suspected abnormal current is obtained according to the value of the noise compensation current, and the wiring harness detection of the washing machine is realized according to the number of suspected abnormal currents and the noise compensation current sequence.

[0011] Further, the method for obtaining the current signal sequence and the current data group is:

[0012] Arrange the current signals according to the sequence of their acquisition time to obtain a current signal sequence;

[0013] The earliest collected current signal is recorded as the initial current signal, and the wire harness temperature at the same collection time as the initial current signal is recorded as the initial wire harness temperature;

[0014] The difference between the wire harness temperature at the time of collection and the initial wire harness temperature is recorded as the temperature difference at the time of collection, and the difference between the current signal corresponding to the time of collection and the initial current signal is recorded as the current difference at the time of collection;

[0015] A pair consisting of the temperature difference and the current difference corresponding to the same acquisition moment is recorded as a current data set at the acquisition moment.

[0016] Furthermore, the method for obtaining the linear term coefficient and the quadratic term coefficient according to the relationship between the current data groups, and then obtaining the temperature influence amplitude, is:

[0017] Taking the temperature difference as the independent variable and the current difference as the dependent variable, the corresponding temperature difference and current difference in all current data groups are fitted to obtain the linear term coefficient and the quadratic term coefficient of the fitted quadratic polynomial;

[0018] The product of the temperature difference at the time of collection and the coefficient of the first-order term is recorded as the first product;

[0019] The product of the square of the temperature difference at the acquisition time and the coefficient of the quadratic term is recorded as the second product;

[0020] The sum of the first product and the second product is recorded as the temperature influence amplitude at the acquisition time.

[0021] Further, the method for obtaining the temperature compensation current according to the temperature influence amplitude and the current data group and obtaining the temperature compensation current sequence according to the acquisition time corresponding to the temperature compensation current is:

[0022] The difference between the temperature difference at the acquisition time and the temperature influence amplitude is recorded as the temperature compensation current at the acquisition time, and the temperature compensation currents are arranged according to the acquisition time corresponding to the temperature compensation currents to obtain a temperature compensation current sequence.

[0023] Further, the method of obtaining the adjacent temperature compensation current of the temperature compensation current according to the time relationship of the acquisition time corresponding to the temperature compensation current, and obtaining the maximum value and the minimum value of the temperature compensation current according to the numerical relationship between the temperature compensation currents included in the temperature compensation current sequence is:

[0024] Taking the first preset threshold time as the time window, recording the temperature compensation current included in the time window as the adjacent temperature compensation current of the temperature compensation current at the center position;

[0025] The temperature compensation current sequence is fitted with a sine function to obtain a fitting curve, and the maximum value point and the minimum value point of the fitting curve are obtained.

[0026] Further, the method for obtaining the amplitude jump coefficient of the temperature compensation current according to the adjacent temperature compensation current, the maximum value of the temperature compensation current and the minimum value of the temperature compensation current is:

[0027] The average of all the maximum values ​​in the time window of the temperature compensation current is recorded as the first maximum value, and the average of all the minimum values ​​in the time window of the temperature compensation current is recorded as the first minimum value;

[0028] The sum of the absolute values ​​of the differences between all the maximum values ​​in the time window of the temperature compensation current and the first maximum value is recorded as the first absolute value, and the sum of the absolute values ​​of the differences between all the minimum values ​​in the time window of the temperature compensation current and the first minimum value is recorded as the second absolute value;

[0029] The sum of the first absolute value and the second absolute value is recorded as the amplitude jump coefficient of the temperature compensation current.

[0030] Further, the method of obtaining the first frequency component according to the numerical relationship between the main frequency and the energy of all frequency components and obtaining the component coefficient of the first frequency component is:

[0031] The frequency component whose energy exceeds the first frequency coefficient times the main frequency energy is recorded as the first frequency component;

[0032] Each first frequency component is recorded as a frequency component to be analyzed, the previous frequency component of the frequency component to be analyzed is recorded as the first frequency component of the frequency component to be analyzed, and the next frequency component of the frequency component to be analyzed is recorded as the second frequency component of the frequency component to be analyzed;

[0033] Recording the difference between the first frequency component of the frequency component to be analyzed and the frequency component to be analyzed as the first difference of the frequency component to be analyzed; recording the difference between the second frequency component of the frequency component to be analyzed and the frequency component to be analyzed as the second difference of the frequency component to be analyzed;

[0034] When the first difference value and the second difference value of the frequency component to be analyzed have the same sign, assigning the component coefficient of the frequency component to be analyzed to a second preset threshold value;

[0035] When the first difference value and the second difference value of the frequency component to be analyzed have different signs, assigning the component coefficient of the frequency component to be analyzed to a third preset threshold value;

[0036] When the product of the first difference and the second difference of the frequency component to be analyzed is 0, the component coefficient of the frequency component to be analyzed is assigned a fourth preset threshold.

[0037] Further, the method for obtaining the spectrum diversity index of the temperature compensation current according to the amplitude jump coefficient, the component coefficient and the first frequency component corresponding to the adjacent temperature compensation current of the temperature compensation current is:

[0038]

[0039] Among them, δ i represents the spectrum diversity index of the temperature compensation current at the i-th acquisition moment; γ i Indicates the amplitude jump coefficient of the temperature compensation current at the i-th acquisition moment; represents the total number of all corresponding first frequency components in the adjacent temperature compensation currents of the temperature compensation current at the i-th acquisition moment; represents the component coefficient of the u-th first frequency component in the adjacent temperature compensation current of the temperature compensation current at the i-th acquisition moment; Represents the energy of the u-th first frequency component in the adjacent temperature compensation current of the temperature compensation current at the i-th acquisition moment.

[0040] Further, the method of obtaining the noise compensation current according to the spectrum diversity index and the temperature compensation current sequence, obtaining the noise compensation current sequence according to the noise compensation current, obtaining the suspected abnormal current according to the value of the noise compensation current, and realizing the wiring harness detection of the washing machine according to the number of suspected abnormal currents and the noise compensation current sequence is as follows:

[0041] Recording the normalized value of the product of the spectrum diversity index of the temperature compensation current at the acquisition time and the temperature compensation current at the acquisition time as the noise compensation current at the acquisition time;

[0042] The noise compensation currents are sorted according to the order of acquisition time to obtain a noise compensation current sequence;

[0043] When the noise compensation current is greater than or equal to the current abnormality threshold, the noise compensation current is considered to be a suspected abnormal current;

[0044] When the ratio of the number of suspected abnormal currents contained in the noise compensation current sequence to the total number of noise compensation currents contained in the noise compensation current sequence is greater than or equal to the first abnormal threshold, it is considered that the wiring harness of the washing machine has a fault; otherwise, it is considered that the wiring harness of the washing machine has no fault.

[0045] In a second aspect, an embodiment of the present invention further provides a wiring harness detection system for a washing machine, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of any one of the above methods when executing the computer program.

[0046] The beneficial effects of the present invention are:

[0047] The present invention obtains a current signal sequence and a current data group by collecting the current signal and the wiring harness temperature when the washing machine is working, and then obtains the temperature influence amplitude, that is, the influence of temperature on current, eliminates the influence of temperature on current in the current signal, obtains a temperature compensation current sequence, and solves the problem of inaccurate wiring harness detection results caused by the influence of temperature on the current signal; then, according to the current signal change caused by the interference of environmental noise, which usually manifests as irregular small random fluctuations and often has no obvious characteristics introduced by frequency components, obtains a spectrum diversity index, and then obtains a noise compensation current according to the spectrum diversity index and the temperature compensation current sequence. The noise compensation current evaluates the confidence that the current fluctuation is caused by the fault under the premise of considering the interference characteristics of the environmental noise, solves the problem of inaccurate wiring harness detection results caused by the influence of other noises such as electromagnetic interference during the wiring harness detection of the washing machine, and makes the detection result have better robustness. Finally, the wiring harness of the washing machine is detected according to the noise compensation current, solves the problem of inaccurate wiring harness detection results, and improves the accuracy of the wiring harness detection results, so as to achieve the purpose of discovering the safety hazards caused by line faults in advance, so as to solve the fault problems in time. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0049] Figure 1 A schematic flow chart of a wiring harness detection method for a washing machine provided by an embodiment of the present invention;

[0050] Figure 2 This is a schematic diagram of abnormal signal performance caused by a fault;

[0051] Figure 3 Schematic diagram of signal abnormality caused by noise. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] See also Figure 1 , which shows a flow chart of a wiring harness detection method for a washing machine provided by an embodiment of the present invention, the method comprising the following steps:

[0054] Step S001, collecting the current signal and the wiring harness temperature when the washing machine is working, and obtaining the current signal sequence and the current data group.

[0055] The Hall effect sensor and the temperature sensor are connected to the wiring harness circuit of the washing machine. The current signal of the washing machine when working is obtained through the Hall effect sensor. The current signal is arranged in the order of the current signal acquisition time through the analog-to-digital converter, and the current signal sequence is obtained and recorded. The wiring harness temperature when each current signal is collected is obtained through the temperature sensor.

[0056] In order to reduce the information loss of the current signal during sampling, the sampling frequency is generally set to 4 to 5 times the maximum frequency of the signal. The washing machine is a commonly used small household appliance and the frequency of household electricity is 50Hz. Therefore, the sampling frequency of the current signal is empirically set to 200Hz.

[0057] The earliest wire harness temperature collected is recorded as the initial wire harness temperature, and the earliest current signal collected is recorded as the initial current signal. The difference between the wire harness temperature corresponding to the collection time and the initial wire harness temperature is recorded as the temperature difference at the collection time, and the difference between the current signal corresponding to the collection time and the initial current signal is recorded as the current difference at the collection time. The binary group consisting of the temperature difference and the current difference corresponding to the same collection time is recorded as the current data group at the collection time.

[0058] At this point, a current signal sequence and a current data set are acquired.

[0059] Step S002, obtaining the linear term coefficient and the quadratic term coefficient according to the relationship between the current data groups, and then obtaining the temperature influence amplitude, obtaining the temperature compensation current according to the temperature influence amplitude and the current data group, and obtaining the temperature compensation current sequence according to the collection time corresponding to the temperature compensation current.

[0060] Using the least square method, with the temperature difference as the independent variable and the current difference as the dependent variable, the corresponding temperature difference and current difference in all current data sets are fitted with a quadratic polynomial to obtain the linear term coefficient and the quadratic term coefficient of the fitted quadratic polynomial. The least square method is a well-known technology and will not be described in detail.

[0061] The temperature influence amplitude is obtained according to the current data set, the linear term coefficient and the quadratic term coefficient of the fitted quadratic polynomial.

[0062] ΔI i =α*(T i -T0)+β*(T i -T0) 2

[0063] In the formula, ΔI i represents the temperature influence amplitude at the i-th acquisition moment; α represents the linear term coefficient of the fitted quadratic polynomial; β represents the quadratic term coefficient of the fitted quadratic polynomial; T i represents the harness temperature at the i-th acquisition moment; T0 represents the initial harness temperature.

[0064] When the difference between the harness temperature at the time of acquisition and the initial harness temperature is greater, the temperature influence at the time of acquisition is greater, that is, the influence of the temperature change on the current signal is greater.

[0065] The temperature compensation current is obtained based on the temperature influence amplitude and current difference at the acquisition time.

[0066] B i =A i -ΔI i

[0067] In the formula, B i represents the temperature compensation current at the i-th acquisition moment; ΔIi A represents the temperature influence amplitude at the i-th acquisition moment; i Represents the temperature difference at the i-th acquisition moment.

[0068] The temperature compensation currents are arranged according to the acquisition times corresponding to the temperature compensation currents to obtain a temperature compensation current sequence.

[0069] At this point, the temperature compensated current sequence is obtained.

[0070] Step S003, obtaining the adjacent temperature compensation current of the temperature compensation current according to the time relationship of the acquisition time corresponding to the temperature compensation current, obtaining the maximum temperature compensation current and the minimum temperature compensation current according to the numerical relationship between the temperature compensation currents contained in the temperature compensation current sequence, and obtaining the amplitude jump coefficient of the temperature compensation current according to the adjacent temperature compensation current, the maximum temperature compensation current and the minimum temperature compensation current.

[0071] When the wiring harness of a washing machine fails, the wiring harness current signal of the washing machine will be affected and fluctuate. At the same time, the wiring harness current signal of the washing machine is also disturbed by environmental noise and will also fluctuate. Therefore, not all current signal fluctuation values ​​represent a line failure.

[0072] Normally, during the operation of a washing machine, when the wiring harness has a poor contact fault, some regular noise signals will be introduced into the current signal, causing the current to exhibit glitches and discontinuities, resulting in large differences between the fluctuation values ​​of the current, and at the same time, introducing additional frequency components in the frequency domain. However, the current signal changes caused by the interference of environmental noise usually appear as irregular small random fluctuations, and are evenly distributed in the frequency domain, often without the introduction of obvious frequency components. Therefore, the analysis can be conducted based on the difference in the noise characterization of the two.

[0073] First, the current signal is analyzed from the perspective of amplitude.

[0074] Taking the first preset threshold time as the time window, the temperature compensation currents contained in the temperature compensation current sequence within the first preset threshold time before and after the temperature compensation current are recorded as the adjacent temperature compensation currents of the temperature compensation current at the center position. The empirical value of the first preset threshold time is 1 second.

[0075] The temperature compensation current sequence is fitted using spline interpolation and sine function to obtain the maximum and minimum points of the fitting curve. The maximum value of the fitting curve is recorded as the maximum value of the temperature compensation current, and the minimum value of the fitting curve is recorded as the minimum value of the temperature compensation current.

[0076] The amplitude jump coefficient of the temperature compensation current is obtained according to the adjacent temperature compensation current, the maximum value of the temperature compensation current and the minimum value of the temperature compensation current.

[0077]

[0078] Among them, γ i Indicates the amplitude jump coefficient of the temperature compensation current at the i-th acquisition moment; represents the jth maximum value of the temperature compensation current among the adjacent temperature compensation currents of the temperature compensation current at the i-th acquisition moment; represents the average value of all the maximum values ​​of the temperature compensation current in the adjacent temperature compensation currents of the temperature compensation current at the i-th acquisition moment; represents the jth temperature compensation current minimum value among the adjacent temperature compensation currents of the temperature compensation current at the i-th acquisition moment; It represents the average of all minimum values ​​of temperature compensation current in the adjacent temperature compensation current of the temperature compensation current at the i-th acquisition moment; N represents the number of maximum values ​​of temperature compensation current in the adjacent temperature compensation current of the temperature compensation current at the i-th acquisition moment; M represents the number of minimum values ​​of temperature compensation current in the adjacent temperature compensation current of the temperature compensation current at the i-th acquisition moment.

[0079] In the adjacent temperature compensation currents of the temperature compensation current, the greater the difference between the maximum values ​​of the temperature compensation current and the greater the difference between the minimum values ​​of the temperature compensation current, the greater the amplitude jump coefficient of the temperature compensation current, that is, the greater the fluctuation difference of the current signal and the more complex the fluctuation situation, at the collection moment corresponding to the temperature compensation current, the fluctuation of the current signal is more likely to be caused by a fault in the wiring harness of the washing machine.

[0080] At this point, the amplitude jump coefficient of the temperature compensation current at each acquisition moment is obtained.

[0081] Step S004, obtaining a frequency response sequence according to the temperature compensated current sequence, obtaining the main frequency and all frequency components of the frequency response sequence, obtaining the first frequency component according to the numerical relationship between the main frequency and the energy of all frequency components, obtaining the component coefficient of the first frequency component, and obtaining the spectrum diversity index of the temperature compensated current according to the amplitude jump coefficient of the temperature compensated current, the component coefficient and the first frequency component corresponding to the adjacent temperature compensated current of the temperature compensated current.

[0082] Secondly, the current signal is analyzed from the frequency domain perspective.

[0083] The temperature compensation current sequence is converted to the frequency domain using FFT fast Fourier transform to obtain the frequency response sequence, wherein the fast Fourier transform is a well-known technology and will not be described in detail.

[0084] Poor contact can cause oscillation or resonance of a specific frequency in the circuit, so the frequency components caused by poor contact usually appear as prominent peaks or peak groups on the spectrum. Noise is random, so noise will appear relatively flat on the spectrum and have energy distribution characteristics at each frequency, without showing obvious peaks or peak groups. The schematic diagram of the abnormal signal caused by the fault is as follows: Figure 2 The schematic diagram of the abnormal signal caused by noise is shown in Figure 3 shown.

[0085] In the spectrum, there are main frequency components with the largest signal strength and frequency components caused by noise or faults. The main frequency is the frequency corresponding to the maximum energy in the largest envelope in the spectrum, and the frequency component is the frequency corresponding to the maximum energy in other envelopes. Get the main frequency and all frequency components of the frequency response sequence.

[0086] Considering the practical significance, the frequency component whose energy exceeds the first frequency coefficient times the main frequency energy is recorded as the first frequency component. The empirical value of the first frequency coefficient is 0.1.

[0087] Each first frequency component is recorded as a frequency component to be analyzed, and only the frequency components to be analyzed are analyzed.

[0088] Each frequency component is recorded as a frequency component to be analyzed, the previous frequency component of the frequency component to be analyzed is recorded as the first frequency component of the frequency component to be analyzed, and the next frequency component of the frequency component to be analyzed is recorded as the second frequency component of the frequency component to be analyzed.

[0089] The difference between the first frequency component of the frequency component to be analyzed and the frequency component to be analyzed is recorded as the first difference of the frequency component to be analyzed; the difference between the second frequency component of the frequency component to be analyzed and the frequency component to be analyzed is recorded as the second difference of the frequency component to be analyzed.

[0090] When the first difference and the second difference of the frequency component to be analyzed have the same sign, the component coefficient of the frequency component to be analyzed is assigned to the second preset threshold; when the first difference and the second difference of the frequency component to be analyzed have different signs, the component coefficient of the frequency component to be analyzed is assigned to the third preset threshold; when the product of the first difference and the second difference of the frequency component to be analyzed is 0, the component coefficient of the frequency component to be analyzed is assigned to the fourth preset threshold. The empirical values ​​of the second preset threshold, the third preset threshold and the fourth preset threshold are 1, -1 and 0 respectively.

[0091] The spectrum diversity index of the temperature compensation current is obtained according to the amplitude jump coefficient and the component coefficient of the temperature compensation current and the first frequency component corresponding to the adjacent temperature compensation current of the temperature compensation current.

[0092]

[0093] Among them, δ i represents the spectrum diversity index of the temperature compensation current at the i-th acquisition moment; γ i Indicates the amplitude jump coefficient of the temperature compensation current at the i-th acquisition moment; represents the total number of all corresponding first frequency components in the adjacent temperature compensation currents of the temperature compensation current at the i-th acquisition moment; represents the component coefficient of the u-th first frequency component in the adjacent temperature compensation current of the temperature compensation current at the i-th acquisition moment; Represents the energy of the u-th first frequency component in the adjacent temperature compensation current of the temperature compensation current at the i-th acquisition moment.

[0094] When the amplitude jump coefficient of the temperature compensation current is larger, the current signal fluctuation is more complex, and the spectrum diversity index at the time of temperature compensation current collection is larger, that is, the current signal fluctuation is more likely to be caused by a washing machine wiring harness failure. When the component coefficient of the frequency component assignment is the second preset threshold, it means that the frequency component is more likely to correspond to the peak or trough position of the frequency curve where the frequency component is located. At the same time, when the frequency peak curve of the frequency component fluctuates more, the frequency component fluctuates more violently, and the spectrum diversity index at the time of temperature compensation current collection is larger, that is, the current signal fluctuation is more likely to be caused by a washing machine wiring harness failure.

[0095] At this point, the spectrum diversity index is obtained.

[0096] Step S005, obtaining a noise compensation current according to a spectrum diversity index and a temperature compensation current sequence, obtaining a noise compensation current sequence according to the noise compensation current, obtaining a suspected abnormal current according to the value of the noise compensation current, and realizing wiring harness detection of the washing machine according to the number of suspected abnormal currents and the noise compensation current sequence.

[0097] A noise compensation current is obtained according to a spectrum diversity index and a temperature compensation current sequence.

[0098] C i =Norm(δ i *B i )

[0099] Among them, C i represents the noise compensation current at the i-th acquisition moment; δ i represents the spectrum diversity index of the temperature compensation current at the i-th acquisition moment; B i represents the temperature compensation current at the i-th acquisition moment; Norm() represents the first value function, which is used to take the linear normalized value in the brackets.

[0100] When the spectrum diversity index and the temperature compensation current are larger, the noise compensation current is larger, that is, the current fluctuation is more likely to be caused by a fault.

[0101] The noise compensation currents are sorted according to the sequence of the noise compensation current collection moments to obtain a noise compensation current sequence.

[0102] When the noise compensation current contained in the noise compensation current sequence is greater than or equal to the current abnormality threshold, the noise compensation current is considered to be a suspected abnormal current, wherein the empirical value of the current abnormality threshold is 0.6.

[0103] When the ratio of the number of suspected abnormal currents contained in the noise compensation current sequence to the total number of noise compensation currents contained in the noise compensation current sequence is greater than or equal to the first abnormal threshold, it is considered that the wiring harness of the washing machine is faulty; otherwise, it is considered that the wiring harness of the washing machine is not faulty.

[0104] At this point, the wiring harness inspection of the washing machine is completed.

[0105] Based on the same inventive concept as the above method, an embodiment of the present invention also provides a wiring harness detection system for a washing machine, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of any one of the above-mentioned wiring harness detection methods for a washing machine when executing the computer program.

[0106] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wiring harness detection method for a washing machine, characterized in that: The method comprises the following steps: Using electrical sensors and temperature sensors to collect current signals and wiring harness temperatures when the washing machine is working, and obtaining current signal sequences and current data groups; Obtain the linear term coefficient and the quadratic term coefficient according to the relationship between the current data groups, and then obtain the temperature influence amplitude, obtain the temperature compensation current according to the temperature influence amplitude and the current data group, and obtain the temperature compensation current sequence according to the acquisition time corresponding to the temperature compensation current; Obtaining the adjacent temperature compensation current of the temperature compensation current according to the time relationship of the acquisition time corresponding to the temperature compensation current, obtaining the maximum value of the temperature compensation current and the minimum value of the temperature compensation current according to the numerical relationship between the temperature compensation currents included in the temperature compensation current sequence, and obtaining the amplitude jump coefficient of the temperature compensation current according to the adjacent temperature compensation current, the maximum value of the temperature compensation current and the minimum value of the temperature compensation current; Obtain a frequency response sequence according to the temperature compensated current sequence, obtain the main frequency and all frequency components of the frequency response sequence, obtain the first frequency component according to the numerical relationship between the main frequency and the energy of all frequency components, obtain the component coefficient of the first frequency component, and obtain the spectrum diversity index of the temperature compensated current according to the amplitude jump coefficient of the temperature compensated current, the component coefficient and the first frequency component corresponding to the adjacent temperature compensated current of the temperature compensated current; The noise compensation current is obtained according to the spectrum diversity index and the temperature compensation current sequence, the noise compensation current sequence is obtained according to the noise compensation current, the suspected abnormal current is obtained according to the value of the noise compensation current, and the wiring harness detection of the washing machine is realized according to the number of suspected abnormal currents and the noise compensation current sequence.

2. A wiring harness detection method for a washing machine according to claim 1, characterized in that: The method for obtaining the current signal sequence and the current data group is as follows: Arrange the current signals according to the sequence of their acquisition time to obtain a current signal sequence; The earliest collected current signal is recorded as the initial current signal, and the wire harness temperature at the same collection time as the initial current signal is recorded as the initial wire harness temperature; The difference between the wire harness temperature at the time of collection and the initial wire harness temperature is recorded as the temperature difference at the time of collection, and the difference between the current signal corresponding to the time of collection and the initial current signal is recorded as the current difference at the time of collection; A pair consisting of the temperature difference and the current difference corresponding to the same acquisition moment is recorded as a current data set at the acquisition moment.

3. A wiring harness detection method for a washing machine according to claim 2, characterized in that: The method for obtaining the linear term coefficient and the quadratic term coefficient according to the relationship between the current data groups, and then obtaining the temperature influence amplitude, is as follows: Taking the temperature difference as the independent variable and the current difference as the dependent variable, the corresponding temperature difference and current difference in all current data groups are fitted to obtain the linear term coefficient and the quadratic term coefficient of the fitted quadratic polynomial; The product of the temperature difference at the time of collection and the coefficient of the first-order term is recorded as the first product; The product of the square of the temperature difference at the acquisition time and the coefficient of the quadratic term is recorded as the second product; The sum of the first product and the second product is recorded as the temperature influence amplitude at the acquisition time.

4. A wiring harness detection method for a washing machine according to claim 2, characterized in that: The method for obtaining the temperature compensation current according to the temperature influence amplitude and the current data group, and obtaining the temperature compensation current sequence according to the acquisition time corresponding to the temperature compensation current is: The difference between the temperature difference at the acquisition time and the temperature influence amplitude is recorded as the temperature compensation current at the acquisition time, and the temperature compensation currents are arranged according to the acquisition time corresponding to the temperature compensation currents to obtain a temperature compensation current sequence.

5. A wiring harness detection method for a washing machine according to claim 1, characterized in that: The method of obtaining the adjacent temperature compensation current of the temperature compensation current according to the time relationship of the acquisition time corresponding to the temperature compensation current, and obtaining the maximum value and minimum value of the temperature compensation current according to the numerical relationship between the temperature compensation currents included in the temperature compensation current sequence is: Taking the first preset threshold time as the time window, recording the temperature compensation current included in the time window as the adjacent temperature compensation current of the temperature compensation current at the center position; The temperature compensation current sequence is fitted with a sine function to obtain a fitting curve, and the maximum value point and the minimum value point of the fitting curve are obtained.

6. A wiring harness detection method for a washing machine according to claim 5, characterized in that: The method for obtaining the amplitude jump coefficient of the temperature compensation current according to the adjacent temperature compensation current, the maximum value of the temperature compensation current and the minimum value of the temperature compensation current is: The average of all the maximum values ​​in the time window of the temperature compensation current is recorded as the first maximum value, and the average of all the minimum values ​​in the time window of the temperature compensation current is recorded as the first minimum value; The sum of the absolute values ​​of the differences between all the maximum values ​​in the time window of the temperature compensation current and the first maximum value is recorded as the first absolute value, and the sum of the absolute values ​​of the differences between all the minimum values ​​in the time window of the temperature compensation current and the first minimum value is recorded as the second absolute value; The sum of the first absolute value and the second absolute value is recorded as the amplitude jump coefficient of the temperature compensation current.

7. A wiring harness detection method for a washing machine according to claim 1, characterized in that: The method of obtaining the first frequency component according to the numerical relationship between the main frequency and the energy of all frequency components and obtaining the component coefficient of the first frequency component is: The frequency component whose energy exceeds the first frequency coefficient times the main frequency energy is recorded as the first frequency component; Each first frequency component is recorded as a frequency component to be analyzed, the previous frequency component of the frequency component to be analyzed is recorded as the first frequency component of the frequency component to be analyzed, and the next frequency component of the frequency component to be analyzed is recorded as the second frequency component of the frequency component to be analyzed; Recording the difference between the first frequency component of the frequency component to be analyzed and the frequency component to be analyzed as the first difference of the frequency component to be analyzed; Recording the difference between the second frequency component of the frequency component to be analyzed and the frequency component to be analyzed as the second difference of the frequency component to be analyzed; When the first difference value and the second difference value of the frequency component to be analyzed have the same sign, assigning the component coefficient of the frequency component to be analyzed to a second preset threshold value; When the first difference value and the second difference value of the frequency component to be analyzed have different signs, assigning the component coefficient of the frequency component to be analyzed to a third preset threshold value; When the product of the first difference and the second difference of the frequency component to be analyzed is 0, the component coefficient of the frequency component to be analyzed is assigned a fourth preset threshold.

8. A wiring harness detection method for a washing machine according to claim 1, characterized in that: The method for obtaining the spectrum diversity index of the temperature compensation current according to the amplitude jump coefficient of the temperature compensation current, the component coefficient and the first frequency component corresponding to the adjacent temperature compensation current of the temperature compensation current is: Among them, δ i represents the spectrum diversity index of the temperature compensation current at the i-th acquisition moment; γ i Indicates the amplitude jump coefficient of the temperature compensation current at the i-th acquisition moment; represents the total number of all corresponding first frequency components in the adjacent temperature compensation currents of the temperature compensation current at the i-th acquisition moment; represents the component coefficient of the u-th first frequency component in the adjacent temperature compensation current of the temperature compensation current at the i-th acquisition moment; Represents the energy of the u-th first frequency component in the adjacent temperature compensation current of the temperature compensation current at the i-th acquisition moment.

9. A wiring harness detection method for a washing machine according to claim 1, characterized in that: The method of obtaining the noise compensation current according to the spectrum diversity index and the temperature compensation current sequence, obtaining the noise compensation current sequence according to the noise compensation current, obtaining the suspected abnormal current according to the value of the noise compensation current, and realizing the wiring harness detection of the washing machine according to the number of suspected abnormal currents and the noise compensation current sequence is as follows: Recording the normalized value of the product of the spectrum diversity index of the temperature compensation current at the acquisition time and the temperature compensation current at the acquisition time as the noise compensation current at the acquisition time; The noise compensation currents are sorted according to the order of acquisition time to obtain a noise compensation current sequence; When the noise compensation current is greater than or equal to the current abnormality threshold, the noise compensation current is considered to be a suspected abnormal current; When the ratio of the number of suspected abnormal currents contained in the noise compensation current sequence to the total number of noise compensation currents contained in the noise compensation current sequence is greater than or equal to the first abnormal threshold, it is considered that the wiring harness of the washing machine has a fault; otherwise, it is considered that the wiring harness of the washing machine has no fault.

10. A wiring harness detection system for a washing machine, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 9 are implemented.

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