Coil inter-turn insulation detection method and device

Abstract

The present invention provides a coil turn-to-turn insulation detection method and device, belonging to the technical field of fault detection. The coil turn-to-turn insulation detection method includes the following steps: setting a first pulse signal and obtaining first characteristic information of the coil under test under the first pulse signal, and drawing a first characteristic curve according to the first characteristic information; setting a second pulse signal and obtaining second characteristic information of the coil under test under the second pulse signal, and drawing a second characteristic curve; subtracting the first characteristic curve from the second characteristic curve to determine a curve to be tested, and using the first standard curve and the second standard curve to determine a verification curve using the same method as that for determining the curve to be tested; and calculating the error between the curve to be tested and the verification curve. The coil turn-to-turn insulation detection device uses the coil turn-to-turn insulation detection method. The coil turn-to-turn insulation detection method and device provided by the present invention reduce the interference of other signals by subtracting, ensure the availability of the original signal, and improve the detection accuracy.

Description

Technical Field

[0001] The invention belongs to the technical field of fault detection, and more specifically, relates to a coil inter-turn insulation detection method and a device using the coil inter-turn insulation detection method. Background Art

[0002] As the service life of high-voltage circuit breakers increases, the risk of hidden dangers caused by insulation aging in the control coils inside the circuit breakers continues to increase. The decline in coil insulation further leads to a decrease in the actual number of turns of the electromagnet coil, which reduces the electromagnet's pull-in ability and eventually leads to circuit breaker control failure, resulting in the circuit breaker being unable to close or open. The circuit breaker electromagnet circuit uses a DC 220V power supply, and its actual control operation time is <70ms, so it is necessary to extract more useful feature data in a shorter time. However, when detecting the coil under test, there will be interference from various types of signals, which reduces the availability of the signal and poor detection accuracy. Summary of the invention

[0003] The purpose of the present invention is to provide a method and device for detecting the insulation between turns of a coil, aiming to solve the problem that the availability of the signal is reduced and the detection accuracy is poor due to the interference of other signals.

[0004] To achieve the above object, the technical solution adopted by the present invention is: to provide a coil turn-to-turn insulation detection method, comprising the following steps:

[0005] Setting a first pulse signal and obtaining first characteristic information of the coil under test under the first pulse signal, and drawing a first characteristic curve according to the first characteristic information; setting a second pulse signal and obtaining second characteristic information of the coil under test under the second pulse signal, and drawing a second characteristic curve according to the second characteristic information;

[0006] Selecting a first standard curve of the coil under test under the first pulse signal, and selecting a second standard curve of the coil under test under the second pulse signal;

[0007] Subtracting the first characteristic curve from the second characteristic curve to determine a test curve, and subtracting the first standard curve from the second standard curve to determine a calibration curve;

[0008] The error of the characteristic parameters in the curve to be measured and the verification curve is calculated to determine the degree of insulation fault of the coil to be measured.

[0009] As another embodiment of the present application, setting a first pulse signal and obtaining first characteristic information of the coil under test under the first pulse signal, and drawing a first characteristic curve according to the first characteristic information; setting a second pulse signal and obtaining second characteristic information of the coil under test under the second pulse signal, and drawing a second characteristic curve according to the second characteristic information includes:

[0010] Setting a specific value of the first pulse signal, and applying the first pulse signal to the coil under test;

[0011] Collecting the first characteristic information generated by the coil under test within a preset pulse time;

[0012] Drawing the first characteristic curve according to the collected first characteristic information;

[0013] Setting the second pulse signal which is different from the specific value of the first pulse signal, and applying the second pulse signal to the coil under test;

[0014] Collecting the second characteristic information generated by the coil under test within the same pulse time;

[0015] The second characteristic curve is drawn according to the collected second characteristic information.

[0016] As another embodiment of the present application, the calculating the error of the characteristic parameters in the curve to be measured and the verification curve includes:

[0017] Overlapping the coordinates of the curve to be measured and the calibration curve;

[0018] Calculating the measured area enclosed by the measured curve and the horizontal axis of the coordinate system and the calibration area enclosed by the calibration curve and the horizontal axis of the coordinate system, and calculating the area error;

[0019] Determine the frequency spectrum information of the curve to be tested and the calibration curve, and calculate the frequency error;

[0020] It is determined whether the area error and the frequency error are within a preset threshold range, thereby determining the degree of insulation fault of the measured coil.

[0021] As another embodiment of the present application, determining the spectrum information of the curve to be measured and the verification curve, and calculating the frequency error includes:

[0022] Calculating the spectrum values ​​of the slice bispectra of the test curve and the verification curve, and determining the maximum frequency values ​​respectively;

[0023] The frequency error between the maximum frequency values ​​of the curve to be measured and the calibration curve is calculated.

[0024] As another embodiment of the present application, before setting a first pulse signal and obtaining first characteristic information of the coil under test under the first pulse signal, and drawing a first characteristic curve according to the first characteristic information; setting a second pulse signal and obtaining second characteristic information of the coil under test under the second pulse signal, and drawing a second characteristic curve according to the second characteristic information, the method includes:

[0025] According to the selected model information of the coil under test, the heating power and pulse time that the coil under test can withstand are determined by the model information;

[0026] According to the model information, standard curves corresponding to the coil under test under various pulse signals are stored.

[0027] The beneficial effect of the coil turn-to-turn insulation detection method provided by the present invention is that, compared with the prior art, the coil turn-to-turn insulation detection method of the present invention first sets a first pulse signal and obtains the first characteristic information generated by the measured coil under the first pulse signal, and draws a first characteristic curve according to the obtained first characteristic information; then sets a second pulse signal, obtains the second characteristic information generated by the measured coil under the second pulse signal, and obtains the second characteristic curve from the second characteristic information. After obtaining the first pulse signal and the second pulse signal, the first standard curve and the second standard curve corresponding to the measured coil under the first pulse signal and the second pulse signal are respectively selected. The curve to be measured is obtained by taking the difference between the first characteristic curve and the second characteristic curve, and the first standard curve and the second standard curve are obtained by taking the difference between the same method to obtain the verification curve. The error of the characteristic parameter between the measured curve and the verification curve is calculated, so as to determine the degree of insulation failure of the measured coil according to the error value. When detecting the insulation state between turns of the coil, there will be interference from various types of signals. In order to improve the accuracy of detection and accurately reflect the insulation condition of the coil under different pulse signals, and because the interference signal does not change much in the pulse signal, the interference signal can be regarded as an approximately constant noise signal added to the characteristic curve. In order to eliminate the interference of the noise signal as much as possible, the first characteristic curve is subtracted from the second characteristic curve so that the noise signal in the obtained curve to be measured is less, which can more truly reflect the characteristics of the coil under test. And the first standard curve and the second standard curve under the same first pulse signal and the second pulse signal are selected under the same coil under test, and the difference between the two is obtained to obtain the verification curve, thereby ensuring the comparability of the curve to be tested and the verification curve. By comparing the errors of the characteristic parameters of the two, the degree of insulation failure of the coil under test can be judged. By making a difference, the interference of other signals is reduced, the availability of the original signal is guaranteed, and the detection accuracy is improved.

[0028] Another object of the present invention is to provide a coil turn-to-turn insulation detection device, comprising:

[0029] An output device, electrically connected to the coil under test, for outputting a pulse signal and receiving characteristic information of the coil under test;

[0030] A control and drawing device, electrically connected to the output device, for controlling the pulse signal output by the output device and drawing a corresponding characteristic curve according to the received characteristic information;

[0031] a calculation device, electrically connected to the control and drawing device, for determining a curve to be measured by subtracting the characteristic curves corresponding to different pulse signals, determining a calibration curve by subtracting the standard curves corresponding to different pulse signals, and calculating an area error and a frequency error between the curve to be measured and the calibration curve; and

[0032] The early warning device analyzes and determines the area error and the frequency error.

[0033] The beneficial effect of the coil turn-to-turn insulation detection device provided by the present invention is that, compared with the prior art, the output device of the coil turn-to-turn insulation detection device of the present invention is electrically connected to the coil to be tested and is used to output a pulse signal to the coil to be tested, by receiving the characteristic information generated by the coil to be tested. The control and drawing device is electrically connected to the output device, and is used to control the pulse signal output by the output device, and is also used to receive the characteristic information to draw a characteristic curve. The calculation module is electrically connected to the control and drawing device, and is used to make a difference between the characteristic curves corresponding to different pulse signals and determine the curve to be tested, make a difference between the standard curves corresponding to different pulse signals and determine the verification curve, and calculate the area error and frequency error between the curve to be tested and the verification curve, and the early warning device determines whether the area error and the frequency error are within the preset threshold range, and determines the degree of insulation failure of the coil to be tested. When detecting the insulation state between turns of the coil, there will be interference from various types of signals. In order to improve the accuracy of detection and accurately reflect the insulation condition of the coil under different pulse signals, and because the interference signal does not change much in the pulse signal, the interference signal can be regarded as an approximately constant noise signal added to the characteristic curve. In order to eliminate the interference of the noise signal as much as possible, the first characteristic curve is subtracted from the second characteristic curve so that the noise signal in the obtained curve to be measured is less, which can more truly reflect the characteristics of the coil under test. And the first standard curve and the second standard curve under the same first pulse signal and the second pulse signal are selected under the same coil under test, and the difference between the two is obtained to obtain the verification curve, thereby ensuring the comparability of the curve to be tested and the verification curve. By comparing the errors of the characteristic parameters of the two, the degree of insulation failure of the coil under test can be judged. By making a difference, the interference of other signals is reduced, the availability of the original signal is guaranteed, and the detection accuracy is improved.

[0034] As another embodiment of the present application, the output device determines the pulse time required to detect the coil under test according to the model information of the coil under test, applies the pulse signal to the coil under test in combination with the model information, and receives the characteristic information.

[0035] As another embodiment of the present application, the control and drawing device includes:

[0036] A CPU, electrically connected to the output device, configured to control the output device and receive the characteristic information;

[0037] A frequency and voltage setter, electrically connected to the CPU, for controlling the output device to output the corresponding pulse signal with the help of the CPU; and

[0038] A characteristic curve display is electrically connected to the CPU and is used to draw the characteristic curve according to the characteristic information.

[0039] As another embodiment of the present application, the computing device includes:

[0040] A positioning module, used for receiving the characteristic curve drawn by the characteristic curve display; positioning the characteristic curve and the standard curve in the same coordinates, and setting the same signal zero point;

[0041] A calculation module, used for performing subtraction of the characteristic curve positioned by the positioning module to determine a curve to be measured and performing subtraction of the standard curve in the same way to determine a calibration curve; and

[0042] The comparison module is used to calculate the measured area and the calibration area enclosed by the measured curve, the calibration curve and the horizontal axis of the coordinates and calculate the area error, and respectively determine the maximum frequency value of the bispectrum of the slices of the measured curve and the calibration curve and calculate the frequency error.

[0043] As another embodiment of the present application, the early warning device is used to receive the area error and the frequency error determined by the comparison module, and issue an early warning when they exceed the threshold range. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 A flow chart of a coil turn-to-turn insulation detection method provided by an embodiment of the present invention;

[0045] Figure 2 A schematic diagram of a coil turn-to-turn insulation detection device provided by an embodiment of the present invention;

[0046] Figure 3 Flowchart for module control and device drawing. DETAILED DESCRIPTION

[0047] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0048] See also Figure 1 The coil turn-to-turn insulation detection method provided by the present invention is now described. The coil turn-to-turn insulation detection method comprises the following steps:

[0049] A first pulse signal is set and first characteristic information of the coil under test under the first pulse signal is obtained, and a first characteristic curve is drawn according to the first characteristic information; a second pulse signal is set and second characteristic information of the coil under test under the second pulse signal is obtained, and a second characteristic curve is drawn according to the second characteristic information.

[0050] A first standard curve of the coil under test under the first pulse signal is selected, and a second standard curve of the coil under test under the second pulse signal is selected.

[0051] The first characteristic curve and the second characteristic curve are subtracted to determine the curve to be tested, and the first standard curve and the second standard curve are subtracted to determine the calibration curve.

[0052] Calculate the error of characteristic parameters in the curve to be tested and the calibration curve to determine the degree of insulation fault of the coil to be tested.

[0053] The beneficial effect of the coil turn-to-turn insulation detection method provided by the present invention is that, compared with the prior art, the coil turn-to-turn insulation detection method of the present invention first sets a first pulse signal and obtains the first characteristic information generated by the measured coil under the first pulse signal, and draws a first characteristic curve according to the obtained first characteristic information; then sets a second pulse signal, obtains the second characteristic information generated by the measured coil under the second pulse signal, and obtains the second characteristic curve from the second characteristic information. After obtaining the first pulse signal and the second pulse signal, the first standard curve and the second standard curve corresponding to the measured coil under the first pulse signal and the second pulse signal are respectively selected. The curve to be measured is obtained by taking the difference between the first characteristic curve and the second characteristic curve, and the first standard curve and the second standard curve are obtained by taking the difference between the same method to obtain the verification curve. The error of the characteristic parameter between the measured curve and the verification curve is calculated, so as to determine the degree of insulation failure of the measured coil according to the error value. When detecting the insulation state between turns of the coil, there will be interference from various types of signals. In order to improve the accuracy of detection and accurately reflect the insulation condition of the coil under different pulse signals, and because the interference signal does not change much in the pulse signal, the interference signal can be regarded as an approximately constant noise signal added to the characteristic curve. In order to eliminate the interference of the noise signal as much as possible, the first characteristic curve is subtracted from the second characteristic curve so that the noise signal in the obtained curve to be measured is less, which can more truly reflect the characteristics of the coil under test. And the first standard curve and the second standard curve under the same first pulse signal and the second pulse signal are selected under the same coil under test, and the difference between the two is obtained to obtain the verification curve, thereby ensuring the comparability of the curve to be tested and the verification curve. By comparing the errors of the characteristic parameters of the two, the degree of insulation failure of the coil under test can be judged. By making a difference, the interference of other signals is reduced, the availability of the original signal is guaranteed, and the detection accuracy is improved.

[0054] As a specific implementation of the coil turn-to-turn insulation detection method provided by the present invention, setting a first pulse signal and obtaining first characteristic information of the coil under test under the first pulse signal, and drawing a first characteristic curve according to the first characteristic information; setting a second pulse signal and obtaining second characteristic information of the coil under test under the second pulse signal, and drawing a second characteristic curve according to the second characteristic information includes:

[0055] The specific value of the first pulse signal is set, and the first pulse signal is applied to the coil under test.

[0056] The first characteristic information generated by the coil under test is collected within a preset pulse time.

[0057] A first characteristic curve is drawn according to the collected first characteristic information.

[0058] A second pulse signal having a specific value different from that of the first pulse signal is set, and the second pulse signal is applied to the coil under test.

[0059] The second characteristic information generated by the coil under test is collected within the same pulse time.

[0060] A second characteristic curve is drawn according to the collected second characteristic information.

[0061] The reduction in the number of turns of the circuit breaker coil under test leads to a reduction in the inductance of the entire circuit breaker coil, thereby changing the oscillation frequency of the entire vibration circuit; and due to the induced electromotive force generated by other coils other than the short-circuit turn in the short-circuit turn, this induced electromotive force will cause a large circulating current in the short-circuit turn, which will generate a demagnetizing field in the coil, reducing the total magnetic field in the entire circuit breaker control coil and reducing the inductance of the circuit breaker control coil, thereby changing the oscillation frequency of the entire oscillation circuit. The circulating current in the short-circuit turn will increase the loss of the circuit breaker control coil, thereby accelerating the voltage and current decay rate of the entire oscillation circuit. Since the existence of the short-circuit turn destroys the original magnetic potential relationship of each layer of the circuit breaker control coil, this will cause the distribution relationship of the current in the circuit breaker control coil, causing a circulating current that runs through the entire coil in the circuit breaker control coil. The existence of this circulating current will also increase the loss of the circuit breaker control coil, accelerating the voltage and current decay rate of the entire oscillation circuit. When there is a short-circuited turn in the circuit breaker control coil, the oscillation frequency and attenuation speed of the voltage or current will change in the pulse voltage method experiment. Therefore, the quality of the insulation of the circuit breaker control coil turns can be judged by observing the voltage at both ends of the coil or the waveform of the current flowing through the coil.

[0062] In the present invention, the first characteristic information and the second characteristic information may include the current value measured by the measured coil under a certain voltage and the corresponding test time. The first characteristic curve and the second characteristic curve drawn by the first characteristic information and the second characteristic information are waveforms with the horizontal axis being the test time and the vertical axis being the current value. In the present invention, high-voltage pulse output and rapid detection technology can be used to obtain the characteristic curve of the measured coil and realize the drawing of the characteristic curve of the measured coil. In order to eliminate the interference of noise on the characteristic curve, two different pulse signals are set, and then two different characteristic information and two different characteristic curves are generated. Since the noise can be approximately regarded as a constant component, by subtracting the two characteristic curves, the interference of the noise can be greatly reduced, and the proportion of the original useful information in the characteristic curve is increased, thereby ensuring the validity of the measurement result.

[0063] As a specific implementation of the coil turn-to-turn insulation detection method provided by the present invention, calculating the error of characteristic parameters in the curve to be tested and the verification curve to determine the degree of insulation fault of the coil to be tested includes:

[0064] Overlap the coordinates of the curve to be tested and the calibration curve.

[0065] Calculate the area to be measured enclosed by the curve to be measured and the horizontal axis of the coordinate system and the calibration area enclosed by the calibration curve and the horizontal axis of the coordinate system, and calculate the area error.

[0066] Determine the frequency spectrum information of the curve to be tested and the calibration curve, and calculate the frequency error.

[0067] It is determined whether the area error and the frequency error are within a preset threshold range, thereby determining the extent of the insulation fault of the coil under test.

[0068] In the present invention, when a pulse signal, i.e., a DC voltage, is applied to both ends of the coil under test, the resistance value in the coil under test is small and can be approximately regarded as a short-circuit state. In order to ensure that the coil under test is not burned or damaged, the time of the applied pulse signal must be very short. The first characteristic curve, the second characteristic curve and the standard curve under the pulse signal of the coil under test are overlapped. After the curves overlap, the first characteristic curve and the second characteristic curve are subtracted to obtain a new curve to be tested. By retrieving the pre-stored waveform data, the model of the coil under test and the characteristic curve under different voltages are found. The first standard curve under the first pulse signal and the second marked curve under the second pulse signal are retrieved. The first standard curve and the second standard curve are subtracted to obtain a verification curve. The area to be tested enclosed by the curve to be tested and the coordinates, and the verification area enclosed by the verification curve and the coordinates are calculated, and the degree of insulation fault of the coil under test is determined by comparing the difference between the two areas. When calculating the curve to be tested and the verification curve, the frequency value and range of the curve to be tested and the verification curve can be calculated after the area error is calculated. By comparing the frequency, the error range with the mark can be reflected, thereby ensuring accurate grasp of the fault. If the area error and frequency error exceed the preset threshold, it can be judged that the measured coil is in a fault state and is unusable. If it does not exceed the threshold range, it can be used as a spare coil.

[0069] As a specific implementation of the coil turn-to-turn insulation detection method provided by the present invention, determining the frequency spectrum information of the curve to be tested and the verification curve, and calculating the frequency error include:

[0070] Calculate the spectrum values ​​of the sliced ​​bispectra of the test curve and the calibration curve, and determine the maximum frequency values ​​respectively.

[0071] Calculate the frequency error between the maximum frequency value of the curve to be tested and the calibration curve.

[0072] In the present invention, the circuit breaker control coil often exhibits a quadratic phase coupling mode. The spectrum suppresses all phase information, is phase blind, and cannot process a large number of non-Gaussian random signals present in the signal. Although the dual spectrum can detect coupling phenomena, it has a large amount of calculation and low estimation accuracy, making it difficult to apply in engineering practice. The noise signal in the control coil of the circuit breaker can be regarded as a Gaussian random signal. In order to effectively and quickly identify the frequency value on the curve, the sliced ​​dual spectrum is a diagonal slice of the third-order cumulant and effectively suppresses the non-quadratic phase coupling harmonic terms in the signal. By measuring the spectrum value of the measured curve and the verification curve, that is, the maximum frequency value, the degree of insulation fault can be more intuitively displayed by comparing the maximum frequency value. The degree of fault in the measured curve and the verification curve can also be indicated by two frequency ranges and the overall area of ​​the frequency.

[0073] As a specific implementation of the coil turn-to-turn insulation detection method provided by the present invention, before setting a first pulse signal and obtaining first characteristic information of the coil under test under the first pulse signal, and drawing a first characteristic curve according to the first characteristic information; setting a second pulse signal and obtaining second characteristic information of the coil under test under the second pulse signal, and drawing a second characteristic curve according to the second characteristic information, it includes:

[0074] According to the model information of the selected coil under test, the heating power and pulse time that the coil under test can withstand are determined based on the model information.

[0075] According to the model information, the standard curves corresponding to the coil under test under various pulse signals are stored.

[0076] In the present invention, in order to ensure that the coil under test is not burned or damaged, a very short pulse signal needs to be applied to the coil under test, so the pulse output time needs to be adjusted when the pulse signal is applied. By selecting the model information of the coil under test, the heating power that the coil under test can withstand is found according to the model information, and then the output time of the pulse signal is adjusted. The pulse signal output time is generally within 10ms. In order to quickly detect the characteristic information within a few milliseconds, a microsecond-level ARM single-chip microcomputer can be used to realize the collection and recording of characteristic information. Different annotation curves can be pre-stored according to the signal information. For example, the standard curve can be obtained by testing with a DC pulse voltage of 300V to 1500V with a span of 100V, and then the degree of insulation fault is judged by calculating the percentage of area error and frequency error between the curve to be tested and the verification curve of the coil under test.

[0077] Another object of the present invention is to provide a coil inter-turn insulation detection device.

[0078] See also Figure 2 The coil turn-to-turn insulation detection device provided by the present invention is now described. The coil turn-to-turn insulation detection method comprises:

[0079] The output device is electrically connected to the coil under test and is used to output a pulse signal and receive characteristic information of the coil under test.

[0080] The control and drawing device is electrically connected to the output device and is used to control the pulse signal output by the output device and draw a corresponding characteristic curve according to the received characteristic information.

[0081] A calculation device, electrically connected to the control and drawing device, for determining a curve to be measured by subtracting characteristic curves corresponding to different pulse signals, determining a calibration curve by subtracting standard curves corresponding to different pulse signals, and calculating an area error and a frequency error between the curve to be measured and the calibration curve;

[0082] Early warning device, analyzes and determines area error and frequency error.

[0083] The beneficial effect of the coil turn-to-turn insulation detection device provided by the present invention is that, compared with the prior art, the output device of the coil turn-to-turn insulation detection device of the present invention is electrically connected to the coil to be tested and is used to output a pulse signal to the coil to be tested, by receiving the characteristic information generated by the coil to be tested. The control and drawing device is electrically connected to the output device, and is used to control the pulse signal output by the output device, and is also used to receive the characteristic information to draw a characteristic curve. The calculation module is electrically connected to the control and drawing device, and is used to make a difference between the characteristic curves corresponding to different pulse signals and determine the curve to be tested, make a difference between the standard curves corresponding to different pulse signals and determine the verification curve, and calculate the area error and frequency error between the curve to be tested and the verification curve, and the early warning device determines whether the area error and the frequency error are within the preset threshold range, and determines the degree of insulation failure of the coil to be tested. When detecting the insulation state between turns of the coil, there will be interference from various types of signals. In order to improve the accuracy of detection and accurately reflect the insulation condition of the coil under different pulse signals, and because the interference signal does not change much in the pulse signal, the interference signal can be regarded as an approximately constant noise signal added to the characteristic curve. In order to eliminate the interference of the noise signal as much as possible, the first characteristic curve is subtracted from the second characteristic curve so that the noise signal in the obtained curve to be measured is less, which can more truly reflect the characteristics of the coil under test. And the first standard curve and the second standard curve under the same first pulse signal and the second pulse signal are selected under the same coil under test, and the difference between the two is obtained to obtain the verification curve, thereby ensuring the comparability of the curve to be tested and the verification curve. By comparing the errors of the characteristic parameters of the two, the degree of insulation failure of the coil under test can be judged. By making a difference, the interference of other signals is reduced, the availability of the original signal is guaranteed, and the detection accuracy is improved.

[0084] As a specific implementation of the coil turn-to-turn insulation detection device provided by the present invention, the output device determines the pulse time required to detect the coil under test according to the model information of the coil under test, applies a pulse signal to the coil under test in combination with the model information, and receives characteristic information.

[0085] In the present invention, the output device determines the size and action time of the input pulse signal according to the model information. In order to ensure that the coil under test is not burned or damaged, a very short pulse signal needs to be applied to the coil under test, so the pulse output time needs to be adjusted when the pulse signal is applied. By selecting the model information of the coil under test, the heating power that the coil under test can withstand is found according to the model information, and then the output time of the pulse signal is adjusted. When applying the pulse signal to the coil under test, the output device can pre-install a pulse signal generator, and install a voltage sensor and a current sensor for sensing the coil under test, the model of the voltage sensor can be FV-EV-1500P1O10, and the model of the current sensor can be HOVS-01S0. The voltage sensor and the current sensor are connected to a signal acquisition and processing device, which can be an NI data acquisition card and a signal amplifier, and the collected waveform data can be directly connected to Labview for display and subsequent analysis and processing. The output device can output different pulse signals according to the settings.

[0086] As a specific implementation of the coil turn-to-turn insulation detection device provided by the present invention, please refer to Figure 3 , the control and drawing device includes:

[0087] The CPU is electrically connected to the output device and is used to control the output device and receive characteristic information.

[0088] The frequency and voltage setter is electrically connected to the CPU and controls the output device to output corresponding pulse signals with the help of the CPU.

[0089] The characteristic curve display is electrically connected to the CPU and is used to draw a characteristic curve according to the characteristic information.

[0090] In the present invention, in order to build a perfect LC oscillation circuit, a high-voltage pulse control technology is used to control the inter-turn insulation detection of the coil, and the V / t characteristic curve of the measured coil is drawn. By comparing the V / t characteristic curve of the measured coil with the standard curve, the aging degree and the inter-turn insulation state of the measured coil are judged, and the detection of the circuit breaking and coil aging defects of the electromagnet coil in the control circuit of the high-voltage circuit breaker can be realized, so as to avoid the control failure caused by the inter-turn insulation failure or operation aging of the control coil of the substation high-voltage circuit breaker.

[0091] As a specific implementation of the coil turn-to-turn insulation detection device provided by the present invention, the calculation device includes:

[0092] The positioning module is used for receiving the characteristic curve drawn by the characteristic curve display; positioning the characteristic curve and the standard curve in the same coordinates, and setting the same signal zero point.

[0093] The operation module is used to obtain the difference of the characteristic curve positioned by the positioning module to determine the curve to be measured and to obtain the difference of the standard curve in the same way to determine the calibration curve.

[0094] The comparison module is used to calculate the measured area and calibration area enclosed by the measured curve, the calibration curve and the horizontal axis of the coordinates and calculate the area error, and respectively determine the maximum frequency value of the bispectrum of the slices of the measured curve and the calibration curve and calculate the frequency error.

[0095] In the present invention, the output device sets a specific value of the first pulse signal, and applies the first pulse signal to the coil under test. The first characteristic information generated by the coil under test is collected within a preset pulse time, and a first characteristic curve is drawn based on the collected first characteristic information. A second pulse signal different from the specific value of the first pulse signal is set, and the second pulse signal is applied to the coil under test. The second characteristic information generated by the coil under test is collected within the same pulse time, and a second characteristic curve is drawn based on the collected second characteristic information.

[0096] The positioning module receives the characteristic curve drawn by the characteristic curve display and positions it in the same coordinate. The calculation module determines the test curve by subtracting the first characteristic curve from the second characteristic curve, and determines the calibration curve by subtracting the first standard curve from the second standard curve.

[0097] The comparison module calculates the error of characteristic parameters in the curve to be tested and the calibration curve to determine the degree of insulation fault of the coil to be tested. The spectrum values ​​of the sliced ​​bi-spectrum of the curve to be tested and the calibration curve are calculated respectively to determine the maximum frequency value.

[0098] As a specific implementation of the coil turn-to-turn insulation detection device provided by the present invention, the early warning device is used to receive the area error and frequency error determined by the comparison module, and issue an early warning when the error exceeds a threshold range.

[0099] In the present invention, the early warning function in the Labview system can be used. Taking 10% as an example, when the preset threshold is exceeded, the Labview system can issue an early warning, thereby facilitating the determination of the degree of insulation fault. At the same time, different levels can be set, for example: exceeding the threshold is an unavailable level, 0-5% is an available level, and 5-10% is a standby level, thereby more intuitively displaying the degree of insulation fault.

[0100] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A coil turn-to-turn insulation detection method, characterized in that it comprises the following steps: Setting a first pulse signal and obtaining first characteristic information of the coil under test under the first pulse signal, and drawing a first characteristic curve according to the first characteristic information; setting a second pulse signal and obtaining second characteristic information of the coil under test under the second pulse signal, and drawing a second characteristic curve according to the second characteristic information; Selecting a first standard curve of the coil under test under the first pulse signal, and selecting a second standard curve of the coil under test under the second pulse signal; Subtracting the first characteristic curve from the second characteristic curve to determine a test curve, and subtracting the first standard curve from the second standard curve to determine a calibration curve; Calculating the error of characteristic parameters in the curve to be measured and the calibration curve; The calculating the error of the characteristic parameters in the curve to be measured and the calibration curve comprises: Overlapping the coordinates of the curve to be measured and the calibration curve; Calculating the measured area enclosed by the measured curve and the horizontal axis of the coordinate system and the calibration area enclosed by the calibration curve and the horizontal axis of the coordinate system, and calculating the area error; Determine the frequency spectrum information of the curve to be tested and the calibration curve, and calculate the frequency error; Determining whether the area error and the frequency error are within a preset threshold range, thereby determining the extent of the insulation fault of the coil under test; The determining of the frequency spectrum information of the curve to be measured and the calibration curve and calculating the frequency error comprises: Calculating the spectrum values ​​of the slice bispectra of the test curve and the verification curve, and determining the maximum frequency values ​​respectively; The frequency error between the maximum frequency values ​​of the curve to be measured and the calibration curve is calculated.

2. The coil turn-to-turn insulation detection method according to claim 1, wherein the first pulse signal is set and first characteristic information of the coil under the first pulse signal is obtained, and a first characteristic curve is drawn according to the first characteristic information; Setting a second pulse signal and acquiring second characteristic information of the coil under test under the second pulse signal, and drawing a second characteristic curve according to the second characteristic information includes: Setting a specific value of the first pulse signal, and applying the first pulse signal to the coil under test; Collecting the first characteristic information generated by the coil under test within a preset pulse time; Drawing the first characteristic curve according to the collected first characteristic information; Setting the second pulse signal which is different from the specific value of the first pulse signal, and applying the second pulse signal to the coil under test; Collecting the second characteristic information generated by the coil under test within the same pulse time; The second characteristic curve is drawn according to the collected second characteristic information.

3. The coil turn-to-turn insulation detection method according to claim 1, wherein before setting a first pulse signal and obtaining first characteristic information of the coil under test under the first pulse signal, and drawing a first characteristic curve according to the first characteristic information; setting a second pulse signal and obtaining second characteristic information of the coil under test under the second pulse signal, and drawing a second characteristic curve according to the second characteristic information, the method comprises: According to the selected model information of the coil under test, the heating power and pulse time that the coil under test can withstand are determined by the model information; According to the model information, standard curves corresponding to the coil under test under various pulse signals are stored.

4. A coil turn-to-turn insulation detection device, characterized in that it includes: An output device, electrically connected to the coil under test, for outputting a pulse signal and receiving characteristic information of the coil under test; A control and drawing device, electrically connected to the output device, for controlling the pulse signal output by the output device and drawing a corresponding characteristic curve according to the received characteristic information; A calculation device, electrically connected to the control and drawing device, for subtracting the characteristic curves corresponding to different pulse signals to determine a curve to be measured, subtracting the standard curves corresponding to different pulse signals to determine a calibration curve, and calculating an area error and a frequency error between the curve to be measured and the calibration curve; and An early warning device for analyzing and determining the area error and the frequency error; The control and drawing device comprises: A CPU, electrically connected to the output device, configured to control the output device and receive the characteristic information; A frequency and voltage setter, electrically connected to the CPU, for controlling the output device to output the corresponding pulse signal with the help of the CPU; and A characteristic curve display, electrically connected to the CPU, for drawing the characteristic curve according to the characteristic information; The computing device comprises: A positioning module, used for receiving the characteristic curve drawn by the characteristic curve display; positioning the characteristic curve and the standard curve in the same coordinates, and setting the same signal zero point; A calculation module, used for performing subtraction of the characteristic curve positioned by the positioning module to determine a curve to be measured and performing subtraction of the standard curve in the same way to determine a calibration curve; and A comparison module, used to calculate the measured area and calibration area enclosed by the measured curve, the calibration curve and the horizontal axis of the coordinates and calculate the area error, and respectively determine the maximum frequency value of the bispectrum of the slices of the measured curve and the calibration curve and calculate the frequency error; The early warning device is used to receive the area error and the frequency error determined by the comparison module, and issue an early warning when they exceed a threshold range.

5. The coil turn-to-turn insulation detection device as described in claim 4 is characterized in that the output device determines the pulse time required to detect the coil under test based on the model information of the coil under test, applies the pulse signal to the coil under test in combination with the model information, and receives the characteristic information.

Images