A high frequency transformer winding coil testing method and system

Abstract

The present invention relates to the technical field of electrical or magnetic variable measurement, and specifically to a method and system for testing a winding coil of a high-frequency transformer. The present invention first obtains the response waveform, impedance data, and phase angle data of the high-frequency transformer at different frequencies; further obtains the resonant frequency, divides the frequency domain of the response waveform to obtain the frequency interval; further divides the frequency interval to obtain the frequency segment; further in each frequency segment, according to the change characteristics of the impedance, the change characteristics of the frequency, the change characteristics of the phase angle, combined with the frequency segment sequence, obtains the weighted leakage inductance parameters and weighted parasitic capacitance parameters of each frequency interval; further according to the difference characteristics of the weighted leakage inductance parameters and the difference characteristics of the weighted parasitic capacitance parameters between different frequency intervals, combined with the difference characteristics of the working frequency and the resonant frequency of the high-frequency transformer, obtains the test result of the high-frequency transformer.

Description

Technical Field

[0001] The invention relates to the technical field of electrical or magnetic variable measurement, and in particular to a method and system for testing a high-frequency transformer winding coil. Background Art

[0002] During the testing of high-frequency transformer winding coils, there may be differences in the actual physical structure and layout of the coils, resulting in resonance caused by the interaction between parasitic capacitance and leakage inductance. This resonance may amplify or weaken the transformer output signal and affect the working stability of the circuit.

[0003] The current method for determining the parasitic capacitance and leakage inductance of the transformer generally separates the relationship between the parasitic capacitance and the leakage inductance based on the resonant frequency. However, since the parasitic capacitance and the leakage inductance have trend changes at different frequencies, and the existing method is a lumped parameter model, the parasitic capacitance and leakage inductance of the transformer winding are equivalent to lumped parameters, ignoring the impact of the response differences of the parasitic capacitance and the leakage inductance to different frequencies, resulting in errors in the measurement results. Summary of the invention

[0004] In order to solve the technical problem that the existing resonant frequency separation method is affected by the trend changes of parasitic capacitance and leakage inductance at different frequencies, resulting in errors in the measurement results, the purpose of the present invention is to provide a high-frequency transformer winding coil testing method and system, and the technical scheme adopted is as follows:

[0005] A method for testing a high-frequency transformer winding coil, the method comprising:

[0006] Obtain the response waveform, impedance data and phase angle data of the high-frequency transformer at different frequencies;

[0007] According to the fluctuation characteristics of the response waveform and the change characteristics of the impedance, the resonant frequency is obtained; based on the resonant frequency, the frequency domain of the response waveform is divided to obtain frequency intervals; according to the fluctuation difference characteristics of the response waveform in each frequency interval, the frequency interval is divided to obtain frequency segments;

[0008] In each frequency segment, according to the variation characteristics of the impedance and the variation characteristics of the frequency, the leakage inductance ratio parameter of each frequency segment is obtained; in each frequency segment, according to the variation characteristics of the phase angle, the parasitic capacitance ratio parameter of each frequency segment is obtained; according to all the leakage inductance ratio parameters and the parasitic capacitance ratio parameters of each frequency interval, combined with the frequency segment sequence, the weighted leakage inductance parameter and the weighted parasitic capacitance parameter of each frequency interval are obtained;

[0009] According to the difference characteristics of the weighted leakage inductance parameters and the difference characteristics of the weighted parasitic capacitance parameters between the different frequency intervals, combined with the difference characteristics of the operating frequency and the resonant frequency of the high-frequency transformer, the test result of the high-frequency transformer is obtained;

[0010] Among them, the frequency segments are sorted in ascending order according to the highest frequency within the frequency segments, and in each frequency interval, the weighted weight of the leakage inductance ratio parameter of each frequency segment is negatively correlated with the serial number of the frequency segment; the weighted weight of the parasitic capacitance ratio parameter of each frequency segment is positively correlated with the serial number of the frequency segment.

[0011] Furthermore, the method for obtaining the resonant frequency includes:

[0012] Obtaining the extreme value points of the response waveform; obtaining the resonance conformity of each extreme value point according to the difference between the amplitude of each extreme value point and the average amplitude of the response waveform, combined with the frequency value corresponding to the extreme value point; the difference between the amplitude of the extreme value point and the average amplitude of the response waveform, and the frequency value are both positively correlated with the resonance conformity;

[0013] According to the difference between the impedance value and the minimum impedance value at the frequency corresponding to each extreme point, combined with the resonance conformity, the resonance possibility of each extreme point is obtained; the difference between the impedance value and the minimum impedance value is negatively correlated with the resonance possibility; the resonance conformity is positively correlated with the resonance possibility;

[0014] The frequency of the extreme point with the greatest resonance possibility is selected as the resonance frequency.

[0015] Furthermore, the method for acquiring the frequency segment includes:

[0016] Select any of the frequency intervals as the frequency segment to be divided; select any non-endpoint frequency in the frequency segment to be divided as the target frequency; obtain the demarcation possibility of each target frequency according to the fluctuation difference characteristics of the response waveform on both sides of the target frequency; when the demarcation possibility is greater than or equal to the preset demarcation threshold, divide the frequency segment to be divided according to the target frequency to obtain the segment to be divided;

[0017] The obtained section to be divided is used again as the frequency segment to be divided, until the demarcation possibilities of all non-endpoint frequencies in the frequency division to be divided are less than the preset demarcation threshold, and the frequency segment to be divided is used as the frequency segment.

[0018] Furthermore, the method for obtaining the leakage inductance ratio parameter includes:

[0019] In each of the frequency segments, the ratio of the absolute value of the impedance difference between the two end points of the frequency segment to the absolute value of the frequency difference is used as the leakage inductance ratio parameter of each of the frequency segments.

[0020] Furthermore, the method for obtaining the parasitic capacitance ratio parameter includes:

[0021] According to the difference between the phase angles corresponding to the two end points of the frequency segment and the preset maximum inductance phase angle, combined with the preset maximum inductance phase angle, the parasitic capacitance ratio parameter of each frequency segment is obtained; the difference between the phase angles corresponding to the two end points of the frequency segment and the preset maximum inductance phase angle is positively correlated with the parasitic capacitance ratio parameter of the frequency segment; the preset maximum inductance phase angle is negatively correlated with the parasitic capacitance ratio parameter of the frequency segment.

[0022] Furthermore, the method for testing the high frequency transformer comprises:

[0023] According to the difference characteristics of the weighted leakage inductance parameters and the difference characteristics of the weighted parasitic capacitance parameters between the different frequency intervals, combined with the difference characteristics of the working frequency and the resonant frequency of the high-frequency transformer, the abnormal coefficient of the high-frequency transformer is obtained; the difference characteristics of the weighted leakage inductance parameters and the difference characteristics of the weighted parasitic capacitance parameters between the different frequency intervals are both positively correlated with the abnormal coefficient; the difference characteristics of the working frequency and the resonant frequency of the high-frequency transformer are negatively correlated with the abnormal coefficient;

[0024] When the abnormal coefficient is greater than or equal to a preset abnormal threshold, the test result of the high-frequency transformer is determined to be a test abnormality.

[0025] Furthermore, the abnormal coefficient is normalized, and the preset abnormal threshold is 0.88.

[0026] Furthermore, after obtaining the test result of the high-frequency transformer, the method further includes:

[0027] For the high-frequency transformer with abnormal test, a resistor-capacitor absorption network is connected in parallel to the winding.

[0028] Furthermore, the frequency interval is divided into a high frequency interval and a low frequency interval; the frequency segment in the high frequency interval is a high frequency segment; and the frequency segment in the low frequency interval is a low frequency segment.

[0029] The present invention also proposes a high-frequency transformer winding coil testing system, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements any one of the steps of the high-frequency transformer winding coil testing method.

[0030] The present invention has the following beneficial effects:

[0031] The present invention first obtains the response waveform, impedance data and phase angle data of the high-frequency transformer at different frequencies to provide a data basis for subsequent analysis; further obtains the resonant frequency and divides the frequency interval with the help of the resonant frequency, analyzes the dominance of leakage inductance and parasitic capacitance in each frequency interval, and prepares for analyzing the influence of resonance on the high-frequency transformer and testing the quality of the winding coil; further, for a more detailed analysis of the dominance of parasitic capacitance and leakage inductance, the frequency interval is divided into frequency segments according to the fluctuation difference characteristics of the response waveform in each frequency interval; further obtains the leakage inductance ratio parameter of each frequency segment to characterize the influence of the leakage inductance on the response waveform; obtains the parasitic capacitance ratio parameter of each frequency segment to characterize the parasitic capacitance ratio parameter of each frequency segment The influence of capacitance on the response waveform; further, according to all the leakage inductance ratio parameters and the parasitic capacitance ratio parameters of each frequency interval, combined with the frequency segment order, the weighted leakage inductance parameters and weighted parasitic capacitance parameters of each frequency interval are obtained, and the overall characteristics of multiple frequency segments of the same type are integrated to characterize the overall influence characteristics within each frequency interval; finally, according to the difference characteristics of the weighted leakage inductance parameters and the weighted parasitic capacitance parameters between different frequency intervals, the difficulty of resonance generation is analyzed, and the difference characteristics of the working frequency of the high-frequency transformer and the resonant frequency are combined to analyze whether the winding coil is suitable for the working state of the high-frequency transformer, and obtain the test results of the high-frequency transformer. The present invention analyzes the dominance and change trend of leakage inductance and parasitic capacitance at different frequencies, combined with the working frequency of the high-frequency transformer, evaluates the difficulty of the winding coil to generate resonance and the degree of suitability for work, and obtains accurate test results for the winding coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are 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 work.

[0033] Figure 1 A flowchart of a high-frequency transformer winding coil testing method provided by one embodiment of the present invention;

[0034] Figure 2 A schematic diagram of a response waveform provided by an embodiment of the present invention;

[0035] Figure 3 A schematic diagram of frequency segment division provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0036] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of a high-frequency transformer winding coil testing method and system proposed by the present invention, its specific implementation method, structure, features and effects, in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0037] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0038] The specific scheme of a high-frequency transformer winding coil testing method and system provided by the present invention is described in detail below with reference to the accompanying drawings.

[0039] See also Figure 1 , which shows a flow chart of a high-frequency transformer winding coil testing method provided by an embodiment of the present invention, specifically comprising:

[0040] Step S1: Acquire the response waveform, impedance data and phase angle data of the high-frequency transformer at different frequencies.

[0041] In order to determine the strength of parasitic capacitance and leakage inductance in the high-frequency transformer, evaluate the degree of influence of resonance on the high-frequency transformer, and obtain the test results of the winding coil, the response waveform, impedance data and phase angle data of the high-frequency transformer at different frequencies are first obtained to provide a data basis for subsequent analysis.

[0042] In one embodiment of the present invention, the response waveform, impedance, phase angle and other data of the high-frequency transformer to be tested at different frequencies are measured by a frequency response analyzer, an oscilloscope and an impedance tester.

[0043] It should be noted that the high-frequency transformer and its test frequency range can be set by the implementer, but the test frequency range must include the resonant frequency. The use of various measuring instruments is already existing technology and will not be repeated here.

[0044] See also Figure 2 , which shows a response waveform schematic diagram provided by an embodiment of the present invention; Figure 2 In the figure, the horizontal axis is frequency, the vertical axis is output voltage, and the waveform in the image is the response waveform of the high-frequency transformer.

[0045] Step S2: Obtain the resonant frequency according to the fluctuation characteristics of the response waveform and the change characteristics of the impedance; divide the frequency domain of the response waveform into frequency intervals based on the resonant frequency; and divide the frequency intervals into frequency segments according to the fluctuation difference characteristics of the response waveform in each frequency interval.

[0046] In the coupled LC circuit of the transformer, due to the geometric winding error of the transformer winding, a part of the magnetic flux fails to couple effectively, resulting in leakage inductance. Parasitic capacitance refers to the capacitance effect formed in a winding coil or other component due to the close distance and relative position between conductors. The combination of parasitic capacitance and leakage inductance usually produces resonance (LC resonance) at high frequencies, resulting in significant impedance changes. The frequency of resonance is called the resonant frequency. This resonance may amplify or weaken the signal and affect the working stability of the circuit.

[0047] Since the degree of dominance of capacitance and inductance on the transformer output waveform varies at different frequencies, at low frequencies, the transformer response waveform is generally affected by inductance, and the effect of capacitance is relatively weak. As the frequency increases, the transformer magnetic field gradually saturates, the dominant role of inductance gradually decreases, and the capacitance effect increases. As the frequency gradually increases, the response of the transformer will suddenly change with the change of capacitance and inductance, and resonance will occur. In order to determine the strength of parasitic capacitance and leakage inductance in the high-frequency transformer, the resonant frequency is first obtained based on the fluctuation characteristics of the response waveform and the change characteristics of the impedance, and then the frequency interval is divided by the resonant frequency, and the dominance of leakage inductance and parasitic capacitance in each frequency interval is analyzed, so as to analyze the influence of resonance on the high-frequency transformer and prepare for testing the quality of the winding coil.

[0048] Preferably, in one embodiment of the present invention, considering that when resonance occurs, the waveform of the output voltage of the high-frequency transformer will have obvious peaks and valleys, and the fluctuation is the most violent, so the resonant frequency exists in the frequency corresponding to the peak value or valley value, and the peak value or valley value corresponds to the extreme point on the response waveform, and the more prominent the amplitude of the extreme point is, the more it conforms to the resonance phenomenon. At the same time, resonance generally occurs at high frequencies, so the extreme point of the response waveform is obtained; according to the difference between the amplitude of each extreme point and the average amplitude of the response waveform, combined with the frequency value corresponding to the extreme point, the resonance conformity of each extreme point is obtained; the difference between the amplitude of the extreme point and the average amplitude of the response waveform, and the frequency value, are both positively correlated with the resonance conformity;

[0049] Considering that when resonance occurs, the lower the impedance, the resonance possibility of each extreme point is obtained based on the difference between the impedance value and the minimum impedance value at the corresponding frequency of each extreme point, combined with the resonance conformity; the difference between the impedance value and the minimum impedance value is negatively correlated with the resonance possibility; the resonance conformity is positively correlated with the resonance possibility;

[0050] The frequency of the extreme point where the resonance possibility is the greatest is selected as the resonance frequency.

[0051] As an example, the calculation formula for the resonance compliance includes:

[0052] ;

[0053] Where i represents the serial number of the extreme value point in the response waveform; Indicates the resonance conformity of the i-th extreme point; Represents the amplitude value of the i-th extreme point; Represents the average amplitude value of the response waveform; Represents the frequency value of the i-th extreme point.

[0054] In the calculation formula of resonance conformity, the prominent characteristics of the amplitude of the extreme point relative to the overall amplitude are shown by comparison. The larger the ratio, the more prominent the amplitude of the extreme point, the more likely resonance will occur, and the greater the resonance conformity. At the same time, the higher the frequency of the extreme point, the more consistent with the characteristics of resonance appearing at high frequencies, the more likely resonance will occur, and the greater the resonance conformity.

[0055] As an example, the calculation formula for the resonance probability includes:

[0056] ;

[0057] Where i represents the serial number of the extreme value point in the response waveform; Indicates the resonance conformity of the i-th extreme point; represents the resonance possibility of the i-th extreme point; Indicates the impedance value corresponding to the frequency of the i-th extreme point; Indicates the minimum value of impedance corresponding to all frequencies; Indicates the preset zero-dividing positive parameter, in this example .

[0058] In the calculation formula for the possibility of resonance, the difference between the impedance value and the minimum impedance value is expressed by taking the difference, dividing it by zero, and taking the reciprocal. The larger it is, that is, the smaller the difference between the impedance value and the minimum impedance value, the more likely resonance is to occur from the impedance perspective, and the greater the possibility of resonance; at the same time The larger it is, the more likely resonance will occur from the waveform perspective, and the greater the possibility of resonance.

[0059] It should be noted that the amplitude value of the extreme point can be represented by the absolute value of the difference between the output voltage value of the extreme point and the average value of the output voltage of all frequencies, and the average amplitude of all frequencies can be represented by the average absolute deviation; in other embodiments of the present invention, the implementer can also calculate the resonance conformity and the resonance possibility through the relevant mapping function, such as , ;in and It represents an exponential function with the natural constant e as the base, and x represents the independent variable.

[0060] After obtaining the resonant frequency, the frequency domain of the response waveform can be divided into frequency intervals based on the resonant frequency, so as to analyze the dominance of leakage inductance and parasitic capacitance in different frequency intervals. Since the emergence of the resonance phenomenon represents the entry into high frequency, the frequency interval is divided into high frequency interval and low frequency interval. The frequency of the low frequency interval is lower than that of the high frequency interval.

[0061] Taking into account the large frequency span within the same frequency interval, each frequency interval is further segmented to more carefully analyze the dominance of parasitic capacitance and leakage inductance. Therefore, the frequency interval is divided into frequency segments according to the fluctuation difference characteristics of the response waveform in each frequency interval.

[0062] Preferably, in one embodiment of the present invention, considering that the greater the difference in the response waveforms on both sides of a certain frequency point in the frequency interval, the more it is necessary to divide the frequency interval by this frequency point, so that the fluctuation of the response waveform in the same frequency segment is more consistent, and the influence characteristics of the parasitic capacitance and leakage inductance in the frequency segment are more stable, which is conducive to improving the accuracy of the dominance of the parasitic capacitance and leakage inductance. Based on this:

[0063] Select any frequency interval as the frequency segment to be divided; select any non-endpoint frequency in the frequency segment to be divided as the target frequency; obtain the demarcation possibility of each target frequency according to the fluctuation difference characteristics of the response waveform on both sides of the target frequency; when the demarcation possibility is greater than or equal to the preset demarcation threshold, divide the frequency segment to be divided according to the target frequency to obtain the segment to be divided;

[0064] The obtained to-be-divided segment is used again as the to-be-divided frequency segment until the demarcation possibilities of all non-endpoint frequencies in the to-be-divided frequency division are less than the preset demarcation threshold, and the to-be-divided frequency segment is used as the frequency segment.

[0065] As an example, taking the low-frequency interval as an example, first obtain the demarcation probability of each target frequency in the low-frequency interval, and the demarcation probability is also linearly normalized. Set the preset demarcation threshold to 0.85. Finally, only one target frequency has a demarcation probability greater than or equal to the preset demarcation threshold, which meets the demarcation condition. The low-frequency interval is divided into two segments to be divided. Then analyze each segment to be divided. All target frequencies in the two segments to be divided do not meet the demarcation condition. Finally, the low-frequency interval is segmented into two frequency segments. Please refer to Figure 3 , which shows a schematic diagram of frequency segment division provided by an embodiment of the present invention;

[0066] The calculation formula for the demarcation probability includes:

[0067] ;

[0068] Wherein, a represents the serial number of the starting frequency of the frequency segment to be divided; b represents the serial number of the ending frequency of the frequency segment to be divided; j represents the serial number of the target frequency in the frequency segment to be divided; represents the demarcation possibility of the jth target frequency in the frequency segment to be divided; u represents the sequence number of the frequency in the frequency segment to be divided on the left side of the target frequency in the frequency segment to be divided; Indicates the output voltage value corresponding to the uth frequency; Indicates the sequence number of the frequency in the frequency segment to be divided, which is on the right side of the target frequency in the frequency segment to be divided; Indicates the output voltage value corresponding to the vth frequency; Used to take absolute values; represents the linear normalization function.

[0069] In the calculation formula of the demarcation possibility, the average output voltage in the response waveform on one side of the target frequency is used to represent the overall characteristics of the response waveform on one side, and the absolute value of the difference is used to represent the fluctuation difference characteristics of the response waveforms on both sides. The larger the absolute value of the difference, the greater the fluctuation difference on both sides of the target frequency, the more it needs to be divided into different frequency segments, and the greater the demarcation possibility.

[0070] It should be noted that the frequency is in the positive direction to the right. In one embodiment of the present invention, the target frequency greater than or equal to the preset demarcation threshold does not belong to any frequency segment. For example, in [1,20], when 12 is used as the target frequency, the left side is [1,11] and the right side is [13,20]. At this time, the demarcation possibility corresponding to 12 is calculated to be 0.95, and [1,20] is divided into [1,11] and [13,20] from 12; at this time, when the target frequency is 2 and 19, there is a situation where there is only one frequency on one side. When the target frequency is specified as the adjacent frequency of the end point frequency of the frequency segment to be divided, the demarcation possibility is 0;

[0071] In other embodiments of the present invention, the implementer may also set the target frequency to belong to one side at the time of division, such as setting the target frequency to belong to the right side, and then calculating the division possibility. When 12 is used as the target frequency, the left side is [1,11] and the right side is [12,20]. At this time, the division possibility corresponding to 12 is calculated to be 0.90, and [1,20] is divided into [1,11] and [12,20] from 12; correspondingly, when the target frequency is 2, there is only one frequency on the left side, and when the target frequency is specified as the adjacent frequency of the left endpoint frequency of the frequency segment to be divided, the division possibility is 0.

[0072] Divide each frequency interval and finally obtain Figure 3As shown in the division result, the frequency segment of the high-frequency interval is the high-frequency segment; the frequency segment of the low-frequency interval is the low-frequency segment.

[0073] Step S3: In each frequency segment, according to the impedance change characteristics and the frequency change characteristics, the leakage inductance ratio parameter of each frequency segment is obtained; in each frequency segment, according to the phase angle change characteristics, the parasitic capacitance ratio parameter of each frequency segment is obtained; according to all the leakage inductance ratio parameters and parasitic capacitance ratio parameters of each frequency interval, combined with the frequency segment sequence, the weighted leakage inductance parameter and weighted parasitic capacitance parameter of each frequency interval are obtained.

[0074] Taking into account that the parasitic capacitance and leakage inductance have different effects on the response waveform in different frequency segments, the leakage inductance ratio parameter and the parasitic capacitance ratio parameter of each frequency segment are calculated respectively to characterize the influence of the leakage inductance and the parasitic capacitance on the response waveform respectively; considering that the leakage inductance impedance and the frequency are linearly positively correlated, the influence of the leakage inductance on the high-frequency transformer can be reflected in the change of impedance and frequency; considering that the influence of the parasitic capacitance on the impedance will cause the phase angle to change, the influence of the parasitic capacitance on the high-frequency transformer can be reflected in the change of the phase angle, so according to the change characteristics of the impedance and the frequency, the leakage inductance ratio parameter of each frequency segment is obtained, and according to the change characteristics of the phase angle, the parasitic capacitance ratio parameter of each frequency segment is obtained.

[0075] Preferably, in one embodiment of the present invention, considering that in each frequency segment, the greater the amplitude of impedance change relative to the amplitude of frequency change, the greater the dominant influence of leakage inductance on the response waveform, so in each frequency segment, the ratio of the absolute value of the difference between the impedances at the two end points of the frequency segment and the absolute value of the difference between the frequencies is used as the leakage inductance ratio parameter of each frequency segment, wherein the absolute value of the difference between the frequencies at the two end points of the frequency segment is the denominator.

[0076] It should be noted that the frequency segment has a certain frequency range, so the denominator must not be zero.

[0077] Preferably, in one embodiment of the present invention, considering that in the LC circuit, the phase angle caused by the impedance of the inductor is +90 degrees, and the phase angle caused by the impedance of the capacitor is -90 degrees, the farther the phase angles of the two end points in the frequency segment are from +90 degrees, the greater the influence of the parasitic capacitance, so +90 degrees is used as the preset maximum inductance phase angle; according to the difference between the phase angles corresponding to the two end points of the frequency segment and the preset maximum inductance phase angle, combined with the preset maximum inductance phase angle, the parasitic capacitance ratio parameter of each frequency segment is obtained;

[0078] The difference between the phase angles corresponding to the two end points of the frequency segment and the preset maximum inductance phase angle is positively correlated with the parasitic capacitance ratio parameter of the frequency segment; the preset maximum inductance phase angle is negatively correlated with the parasitic capacitance ratio parameter of the frequency segment.

[0079] As an example, the calculation formula of the parasitic capacitance ratio parameter in any frequency range includes:

[0080] ;

[0081] Wherein, E represents the parasitic capacitance ratio parameter of the frequency segment; Indicates the preset maximum inductance phase angle; Indicates the phase angle corresponding to the right endpoint frequency of the frequency segment; Indicates the phase angle corresponding to the left endpoint frequency of the frequency segment.

[0082] In the calculation formula of the parasitic capacitance ratio parameter, It represents the difference between the phase angle corresponding to the two end points of the frequency segment and the preset maximum inductance phase angle, and represents the degree of deviation of the phase angle in the frequency segment relative to the preset maximum inductance phase angle. The greater the deviation, the greater the influence of the parasitic capacitance, the stronger the dominance, and the larger the parasitic capacitance ratio parameter.

[0083] Considering that in the low-frequency range, the influence of leakage inductance on the response waveform is more obvious than that of parasitic capacitance, while in the high-frequency range, the influence of parasitic capacitance is more obvious, and the dominant factor changes before and after resonance, the weighted leakage inductance parameters and weighted parasitic capacitance parameters of each frequency range are calculated respectively, and the overall characteristics of multiple frequency ranges of the same type are integrated; considering that the order of frequency ranges represents the high and low frequencies between frequency ranges, the influence of leakage inductance and parasitic capacitance will change with frequency, so the order of frequency ranges needs to be combined in weighted calculation to characterize the overall influence characteristics in each frequency range;

[0084] Among them, the frequency segments are sorted in ascending order by the highest frequency in the frequency segment. The higher the frequency, the smaller the influence of leakage inductance, and the confidence of the leakage inductance ratio parameter is gradually reduced. Therefore, in each frequency interval, the weighted weight of the leakage inductance ratio parameter of each frequency segment is negatively correlated with the serial number of the frequency segment; the higher the frequency, the greater the influence of parasitic capacitance, and the confidence of the parasitic capacitance ratio parameter is gradually increased. Therefore, the weighted weight of the parasitic capacitance ratio parameter of each frequency segment is positively correlated with the serial number of the frequency segment.

[0085] As an example, the calculation formula of the weighted leakage inductance parameter in the low frequency range includes:

[0086] ;

[0087] in, Represents the weighted leakage inductance parameter of the low-frequency interval; low represents the low-frequency interval identifier; represents the number of low-frequency segments in the low-frequency interval; m represents the sequence number of the low-frequency segment in the low-frequency interval; It represents the leakage inductance ratio parameter of the mth low-frequency interval in the low-frequency interval; Represents the sum of the serial numbers of all low-frequency segments in the low-frequency interval; Represents the weighted weight of the leakage inductance ratio parameter of the mth low-frequency interval in the low-frequency interval.

[0088] In the calculation formula of the weighted leakage inductance parameter of the low-frequency interval, the larger the serial number of the low-frequency segment is, the higher the frequency of the low-frequency segment is, and the smaller the weighted weight assigned to the corresponding leakage inductance ratio parameter is.

[0089] By analogy, the calculation formula for the weighted leakage inductance parameter in the high frequency range includes:

[0090] ;

[0091] in, represents the weighted leakage inductance parameter of the high-frequency interval; high represents the high-frequency interval identifier; N represents the number of high-frequency segments in the high-frequency interval; n represents the sequence number of the high-frequency segment in the high-frequency interval; It represents the leakage inductance ratio parameter of the nth high-frequency interval in the high-frequency interval; Represents the sum of the serial numbers of all high-frequency segments in the high-frequency interval; Represents the weighted weight of the leakage inductance ratio parameter of the nth high-frequency interval in the high-frequency interval.

[0092] The calculation formula of the weighted parasitic capacitance parameters in the low-frequency range includes:

[0093] ;

[0094] in, Represents the weighted parasitic capacitance parameter of the low-frequency interval; low represents the low-frequency interval identifier; represents the number of low-frequency segments in the low-frequency interval; m represents the sequence number of the low-frequency segment in the low-frequency interval; It represents the parasitic capacitance ratio parameter of the mth low-frequency interval in the low-frequency interval; Represents the sum of the serial numbers of all low-frequency segments in the low-frequency interval; Represents the weighted weight of the parasitic capacitance ratio parameter of the mth low-frequency interval in the low-frequency interval.

[0095] In the calculation formula of the weighted parasitic capacitance parameter of the low-frequency interval, the larger the serial number of the low-frequency section, the higher the frequency of the low-frequency section, and the greater the weighted weight assigned to the corresponding parasitic capacitance ratio parameter.

[0096] By analogy, the calculation formula for the weighted parasitic capacitance parameters in the high frequency range includes:

[0097] ;

[0098] in, represents the weighted parasitic capacitance parameter of the high-frequency interval; high represents the high-frequency interval identifier; N represents the number of high-frequency sections in the high-frequency interval; n represents the sequence number of the high-frequency section in the high-frequency interval; It represents the parasitic capacitance ratio parameter of the nth high-frequency interval in the high-frequency interval; Represents the sum of the serial numbers of all high-frequency segments in the high-frequency interval; Represents the weighted weight of the parasitic capacitance ratio parameter of the nth high-frequency interval in the high-frequency interval.

[0099] At this point, the weighted leakage inductance parameters and weighted parasitic capacitance parameters of each frequency interval are obtained, providing a basis for the subsequent acquisition of test results of the high-frequency transformer winding coil.

[0100] Step S4: According to the difference characteristics of the weighted leakage inductance parameters and the weighted parasitic capacitance parameters between different frequency intervals, combined with the difference characteristics of the operating frequency and the resonant frequency of the high-frequency transformer, the test result of the high-frequency transformer is obtained.

[0101] Taking into account the difference characteristics of the weighted leakage inductance parameters and the difference characteristics of the weighted parasitic capacitance parameters between different frequency intervals, it reflects the difficulty of resonance generation, and thus reflects the quality of the winding coil; at the same time, the difference characteristics of the operating frequency and the resonant frequency of the high-frequency transformer reflect whether the winding coil is suitable for the working state of the high-frequency transformer. Therefore, according to the difference characteristics of the weighted leakage inductance parameters and the difference characteristics of the weighted parasitic capacitance parameters between different frequency intervals, combined with the difference characteristics of the operating frequency and the resonant frequency of the high-frequency transformer, the test results of the high-frequency transformer are obtained.

[0102] Preferably, in one embodiment of the present invention, considering that as the frequency gradually increases, the greater the degree of reduction of the weighted leakage inductance parameter in different frequency intervals, and the greater the degree of increase of the parasitic capacitance, it means that resonance is more likely to occur; the closer the resonant frequency is to the operating frequency of the high-frequency transformer, the worse the working state of the high-frequency transformer, which will increase the loss and stress of the transformer, and the less suitable the winding coil is for the high-frequency transformer, based on this:

[0103] According to the difference characteristics of the weighted leakage inductance parameters and the weighted parasitic capacitance parameters between different frequency intervals, combined with the difference characteristics of the working frequency and the resonant frequency of the high-frequency transformer, the abnormal coefficient of the high-frequency transformer is obtained; the difference characteristics of the weighted leakage inductance parameters and the weighted parasitic capacitance parameters between different frequency intervals are positively correlated with the abnormal coefficient; the difference characteristics of the working frequency and the resonant frequency of the high-frequency transformer are negatively correlated with the abnormal coefficient;

[0104] When the abnormal coefficient is greater than or equal to the preset abnormal threshold, the test result of the high-frequency transformer is determined to be a test abnormality.

[0105] As an example, the calculation formula of the anomaly coefficient includes:

[0106] ;

[0107] Where W represents the abnormal coefficient of the high-frequency transformer; represents the linear normalization function; Represents the weighted leakage inductance parameter in the low frequency range; Represents the weighted leakage inductance parameter in the high frequency range; Represents the weighted parasitic capacitance parameter in the low frequency range; Represents the weighted parasitic capacitance parameter in the high frequency range; Indicates the operating frequency of the high-frequency transformer; represents the resonant frequency; Indicates taking the absolute value; Indicates the preset zero-dividing positive parameter, in this example .

[0108] In the calculation formula of the abnormal coefficient, The larger the value, the greater the decrease of the weighted leakage inductance parameter with the increase of frequency. The larger it is, the greater the increase in parasitic capacitance is. Combining the two, it means that the high-frequency transformer is more likely to resonate, the greater the degree of influence of resonance is, and the greater the abnormal coefficient is. The smaller it is, the closer the resonant frequency is to the operating frequency of the high-frequency transformer, the easier it is for the working state of the high-frequency transformer to be abnormal, and the larger the abnormality coefficient.

[0109] It should be noted that, in one embodiment of the present invention, the preset abnormal threshold is 0.88, and the sample set is formed by the historical winding coil test results, so as to perform normalization and determine the test results; in other embodiments of the present invention, the implementer may also use the inverse sine function Mapping, such as ,in represents the sensitivity coefficient, is a positive number, The smaller it is, the lower the sensitivity of the inverse sine function, that is, the less likely it is to approach the extreme value. Represents the independent variable. Since the sensitivity coefficient is closely related to the preset abnormal threshold, and different implementation scenarios have different performance requirements for high-frequency transformers, the sensitivity coefficient and the preset abnormal threshold are no longer limited here.

[0110] It should be noted that the operating frequency of the high-frequency transformer can be obtained from a work manual or a design specification and is not limited here.

[0111] It should be noted that obtaining the test results of the high-frequency transformer also includes:

[0112] For transformers with abnormal coil performance, staggered windings can be used to disperse the concentrated effect of inter-turn capacitance and reduce the total parasitic capacitance. The primary and secondary windings can be wound close to or staggered to increase flux coupling and reduce leakage inductance. A resistor-capacitor absorption network can also be connected in parallel to the winding to suppress high-frequency interference near the resonant frequency, thereby improving the performance and reliability of the transformer under high-frequency conditions.

[0113] An embodiment of the present invention also provides a high-frequency transformer winding coil testing system, the system includes a memory, a processor and a computer program, wherein the memory is used to store the corresponding computer program, the processor is used to run the corresponding computer program, and when the computer program runs in the processor, it can implement a high-frequency transformer winding coil testing method described in steps S1-S4.

[0114] In summary, in order to solve the technical problem that the existing resonant frequency separation method is affected by the trend change of parasitic capacitance and leakage inductance at different frequencies, resulting in errors in the measurement results, the present invention proposes a high-frequency transformer winding coil testing method and system. The present invention first obtains the response waveform, impedance data and phase angle data of the high-frequency transformer at different frequencies; further obtains the resonant frequency, divides the frequency domain of the response waveform to obtain the frequency interval; further divides the frequency interval to obtain the frequency segment; further in each frequency segment, according to the change characteristics of the impedance, the change characteristics of the frequency, the change characteristics of the phase angle, combined with the frequency segment sequence, obtain the weighted leakage inductance parameters and weighted parasitic capacitance parameters of each frequency interval; further according to the difference characteristics of the weighted leakage inductance parameters and the difference characteristics of the weighted parasitic capacitance parameters between different frequency intervals, combined with the difference characteristics of the working frequency and the resonant frequency of the high-frequency transformer, obtain the test results of the high-frequency transformer.

[0115] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0116] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A method for testing a high-frequency transformer winding coil, characterized in that: The method comprises: Obtain the response waveform, impedance data and phase angle data of the high-frequency transformer at different frequencies; According to the fluctuation characteristics of the response waveform and the change characteristics of the impedance, the resonant frequency is obtained; based on the resonant frequency, the frequency domain of the response waveform is divided to obtain frequency intervals; according to the fluctuation difference characteristics of the response waveform in each frequency interval, the frequency interval is divided to obtain frequency segments; In each frequency segment, according to the variation characteristics of the impedance and the variation characteristics of the frequency, the leakage inductance ratio parameter of each frequency segment is obtained; in each frequency segment, according to the variation characteristics of the phase angle, the parasitic capacitance ratio parameter of each frequency segment is obtained; according to all the leakage inductance ratio parameters and the parasitic capacitance ratio parameters of each frequency interval, combined with the frequency segment sequence, the weighted leakage inductance parameter and the weighted parasitic capacitance parameter of each frequency interval are obtained; According to the difference characteristics of the weighted leakage inductance parameters and the difference characteristics of the weighted parasitic capacitance parameters between the different frequency intervals, combined with the difference characteristics of the operating frequency and the resonant frequency of the high-frequency transformer, the test result of the high-frequency transformer is obtained; The frequency interval is divided into a high frequency interval and a low frequency interval; the frequency segment in the high frequency interval is a high frequency segment; the frequency segment in the low frequency interval is a low frequency segment; The frequency segments are sorted in ascending order by the highest frequency in the frequency segments, and in each frequency interval, the weighted weight of the leakage inductance ratio parameter of each frequency segment is negatively correlated with the sequence number of the frequency segment; the weighted weight of the parasitic capacitance ratio parameter of each frequency segment is positively correlated with the sequence number of the frequency segment; The method for obtaining the leakage inductance ratio parameter includes: In each of the frequency segments, a ratio of an absolute value of a difference in the impedances at two end points of the frequency segment to an absolute value of a difference in the frequencies is used as a leakage inductance ratio parameter of each of the frequency segments; The method for obtaining the parasitic capacitance ratio parameter includes: According to the difference between the phase angles corresponding to the two end points of the frequency segment and the preset maximum inductance phase angle, combined with the preset maximum inductance phase angle, the parasitic capacitance ratio parameter of each frequency segment is obtained; the difference between the phase angles corresponding to the two end points of the frequency segment and the preset maximum inductance phase angle is positively correlated with the parasitic capacitance ratio parameter of the frequency segment; the preset maximum inductance phase angle is negatively correlated with the parasitic capacitance ratio parameter of the frequency segment.

2. A high-frequency transformer winding coil testing method according to claim 1, characterized in that: The method for obtaining the resonant frequency includes: Obtaining the extreme value points of the response waveform; obtaining the resonance conformity of each extreme value point according to the difference between the amplitude of each extreme value point and the average amplitude of the response waveform, combined with the frequency value corresponding to the extreme value point; the difference between the amplitude of the extreme value point and the average amplitude of the response waveform, and the frequency value are both positively correlated with the resonance conformity; According to the difference between the impedance value and the minimum impedance value at the frequency corresponding to each extreme point, combined with the resonance conformity, the resonance possibility of each extreme point is obtained; the difference between the impedance value and the minimum impedance value is negatively correlated with the resonance possibility; the resonance conformity is positively correlated with the resonance possibility; The frequency of the extreme point with the greatest resonance possibility is selected as the resonance frequency.

3. A high-frequency transformer winding coil testing method according to claim 1, characterized in that: The method for acquiring the frequency segment includes: Select any of the frequency intervals as the frequency segment to be divided; select any non-endpoint frequency in the frequency segment to be divided as the target frequency; obtain the demarcation possibility of each target frequency according to the fluctuation difference characteristics of the response waveform on both sides of the target frequency; when the demarcation possibility is greater than or equal to the preset demarcation threshold, divide the frequency segment to be divided according to the target frequency to obtain the segment to be divided; The obtained segment to be divided is used again as the frequency segment to be divided, until the demarcation possibilities of all non-endpoint frequencies in the frequency segment to be divided are less than the preset demarcation threshold, and the frequency segment to be divided is used as the frequency segment.

4. A high-frequency transformer winding coil testing method according to claim 1, characterized in that: The method for obtaining the test result of the high-frequency transformer includes: According to the difference characteristics of the weighted leakage inductance parameters and the difference characteristics of the weighted parasitic capacitance parameters between the different frequency intervals, combined with the difference characteristics of the working frequency and the resonant frequency of the high-frequency transformer, the abnormal coefficient of the high-frequency transformer is obtained; the difference characteristics of the weighted leakage inductance parameters and the difference characteristics of the weighted parasitic capacitance parameters between the different frequency intervals are both positively correlated with the abnormal coefficient; the difference characteristics of the working frequency and the resonant frequency of the high-frequency transformer are negatively correlated with the abnormal coefficient; When the abnormal coefficient is greater than or equal to a preset abnormal threshold, the test result of the high-frequency transformer is determined to be a test abnormality.

5. A high-frequency transformer winding coil testing method according to claim 4, characterized in that: The abnormal coefficient is also normalized, and the preset abnormal threshold is 0.

88.

6. A high-frequency transformer winding coil testing method according to claim 4, characterized in that: After obtaining the test result of the high frequency transformer, the method further includes: For the high-frequency transformer with abnormal test, a resistor-capacitor absorption network is connected in parallel to the winding.

7. A high-frequency transformer winding coil testing system, the system comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the steps of a high-frequency transformer winding coil testing method as described in any one of claims 1 to 6 are implemented.

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