Fault detection system of mining high-voltage frequency converter

Abstract

The invention discloses a fault detection system of a mining high-voltage frequency converter, which relates to the field of fault detection of high-voltage frequency converters and comprises a server connected with a data acquisition module, an appearance module, a static module, a dynamic module and an early warning module. According to the method, the element crack, the element scorching state and the capacitor swelling state of the high-voltage frequency converter are analyzed to obtain the observation abnormal state value of the mining high-voltage frequency converter, and the resistance, insulation and capacitance parameters of the high-voltage frequency converter are analyzed through the static information of the high-voltage frequency converter to obtain the electric static value of the mining high-voltage frequency converter. The method comprises the following steps: performing output voltage analysis of the high-voltage frequency converter after braking on dynamic information of the mining high-voltage frequency converter to obtain a dynamic electric value of the mining high-voltage frequency converter, and analyzing to obtain a running state of the mining high-voltage frequency converter and early warning measures corresponding to the high-voltage frequency converter in different running states, thereby reducing the frequency of fault occurrence of the high-voltage frequency converter and improving the reliability of the mining high-voltage frequency converter. And the coal mining cost of an enterprise is reduced.

Description

Technical Field

[0001] The invention relates to the field of high-voltage frequency converter fault detection, in particular to a fault detection system for a high-voltage frequency converter used in a mine. Background Art

[0002] Coal mines face dangers such as humidity and high-concentration dust during mining. Dust and humid air can easily cause high-voltage inverter operation failures. At the same time, high-voltage inverters themselves contain complex power electronic topology structures. The long-term operation of components at high voltages increases the probability of failures, further leading to safety accidents and increasing corporate costs. Traditional detection work relies too much on manual simple instrument detection and appearance observation, and cannot guarantee accuracy.

[0003] In the fault detection operation of existing mining high-voltage inverters, it is often impossible to deeply identify the operating status of the high-voltage inverter from multiple angles, nor to accurately evaluate the high-voltage inverter faults in a timely manner, let alone adopt different early warning measures for different fault conditions. As a result, the frequency of high-voltage inverter failures increases, which increases the cost of coal mining for enterprises and also increases the risk of mining to a certain extent.

[0004] In order to solve the above defects, a technical solution is now provided. Summary of the invention

[0005] In order to solve the technical problems raised by the above background technology, the present invention is proposed. An embodiment of the present invention provides a fault detection system for a high-voltage frequency converter for mining.

[0006] The purpose of the present invention can be achieved through the following technical solutions: A fault detection system for a high-voltage frequency converter for mining includes a server, and the server is connected with a data acquisition module, an appearance module, a static module, a dynamic module and an early warning module.

[0007] The data acquisition module is used to collect circuit element information, capacitance information, static information and dynamic information of the mining high-voltage inverter, and send it to the appearance module, static module and dynamic module.

[0008] The appearance module analyzes the component cracks, component burnt states and capacitor bulging states of the high-voltage inverter for mining through the circuit component information and capacitor information of the high-voltage inverter for mining, and obtains the abnormal state value of the high-voltage inverter for mining; The static module analyzes the resistance, insulation and capacitance parameters of the high-voltage inverter through the static information of the high-voltage inverter to obtain the static value of the mining high-voltage inverter; The dynamic module performs post-control output voltage analysis on the dynamic information of the mining high-voltage inverter to obtain the dynamic electric value of the mining high-voltage inverter; The early warning module is used to receive the observed abnormal state value, the static value and the dynamic value of the high-voltage inverter for mining, and analyze the operating status of the high-voltage inverter for mining based on this, and compare it with the set operating status reference range to obtain the corresponding early warning measures for the high-voltage inverter under different operating conditions.

[0009] Furthermore, the steps of analyzing the abnormal value of the mining high-voltage inverter are as follows: Get the original maximum width and maximum length of the capacitor housing, and the width and length of the corresponding position, divide the width of the corresponding position by the original maximum width, divide the length by the original maximum length, and sum them up to get the capacitor drum value, normalize the component cracking deviation value, circuit component burnt value, circuit component burnt over-domain rate and capacitor drum value, use the component cracking deviation value as the radius of the circle on the cone, the circuit component burnt value as the radius of the circle below the cone, and the circuit component burnt over-domain rate as the cone height to construct a cone, the center of the circle on the cone is the center of the sphere, and the capacitor drum value is used as the radius of the sphere to construct a sphere, identify the irregular volume formed by the sphere and the cone, and mark it as the observed abnormal value Gyz of the mining high-voltage inverter.

[0010] Furthermore, the steps of analyzing the component cracking deviation value are as follows: Step 1: An industrial camera is set at the high-voltage inverter to obtain an image of the internal circuit components, and grayscale processing is performed to convert it into a component grayscale image. The grayscale histogram distribution of the component image is adjusted to stretch the grayscale range. The grayscale image is binarized by setting a threshold through grayscale histogram distribution feature analysis. The cracked area is black and other areas are white. The edge contour of the cracked area is extracted through an edge detection operator to obtain the crack edge contour of the component. Step 2: Obtain the crack edge contour curve of the component and discretize the curve into coordinate points (x i ,y i ), i is the coordinate point number, and the formula is used to calculate the component crack bending energy value Nl; Step 3: Calculate the slope of the coordinate difference between each coordinate point and the adjacent point of the crack edge contour curve of the component to obtain the tangent direction of each coordinate point of the crack edge contour, and obtain the angle between each oblique line direction and the right horizontal line. When the oblique line direction is negative below the right horizontal line, count the difference between the maximum and minimum angles to obtain the extreme value, sort each contour coordinate point in the order of coordinate point numbers, subtract the angle in the front from the angle in the back, and take the absolute value, count the sum of the absolute values ​​of the angle differences to obtain the total difference, perform weighted calculation on the extreme value and the total difference, and multiply them by the corresponding weight factor coefficients to obtain the component crack deviation value; Step 4: Count the number of cracks in the component, the total length of the cracks and the average of the crack width, and sum them to obtain the total length of the cracks in the component. Divide the crack grayscale image into several regions, count the sum of the number of cracks, the length of the cracks and the average of the crack width in each region, and obtain the length of the cracks in each region. Calculate the average crack length. Subtract the average crack length from the length of the cracks in each region and sum the squares to obtain the variance of the crack length of the component. Divide the variance of the crack length of the component by the average crack length to obtain the coefficient of variation of the cracks in the component. Step 5: The component crack deviation value, the total crack length value of the component and the component crack variation coefficient are combined with the component crack bending energy value Nl to calculate the component crack deviation value YKY.

[0011] Furthermore, the steps for analyzing the circuit element burnt value and the circuit element burnt out-of-domain rate are as follows: The internal circuit component image is converted into an HSV image according to the color space conversion algorithm, where H represents hue, S represents saturation, and V represents brightness. The HSV color space reference threshold range WT1 is set. The reference threshold range WT1 is that the brightness value V is less than 0.35 and the saturation S is greater than 0.25 and less than 0.85. When the HSV value in the HSV image is within the color space reference threshold range WT1, the point corresponds to the burnt point, and the HSV values ​​of each point in each HSV image are traversed to obtain the burnt area. The number of pixels in each burnt area is counted, and the sum is divided by the total pixel value to obtain the burnt value of the circuit component. The edges of each burnt area, and two 3×3 matrices of each edge point in each burnt area are established, which are horizontal direction matrix and vertical direction matrix, and the horizontal gradient value STDn of each edge point and the vertical gradient value CTDn of each edge point are calculated, and the horizontal gradient value of each edge point and the vertical gradient value of each edge point are summed and calculated, and multiplied by the correction factor coefficient to obtain the gradient value of each edge point, and the sum is divided by the number of edge points and multiplied by the correction coefficient t1 to obtain the focus gradient value of each area, and the number of areas with focus gradient values ​​greater than the set area focus gradient threshold value of each area is counted, and divided by the total number of areas to obtain the circuit component burnt out-of-domain rate.

[0012] Furthermore, the electrostatic value analysis steps of the mining high-voltage inverter are as follows: Mark the absolute value of the high-voltage inverter part, the bias value of the high-voltage inverter power supply group and the high-voltage inverter capacitance parameter value as dj, zp and cy respectively, according to the set formula , and the static value Djz of the high-voltage inverter for mining is obtained, where txt1, txt2 and txt3 are the reference weight factor coefficients for the absolute value of the high-voltage inverter part, the bias value of the high-voltage inverter standby group and the parameter value of the high-voltage inverter capacitance, respectively, and λ is the correction factor coefficient.

[0013] Furthermore, the steps of analyzing the absolute value of the high-voltage inverter part, the bias value of the high-voltage inverter power reserve group and the capacitance parameter value of the high-voltage inverter are as follows: The insulation resistance meter is used to measure the insulation to ground and phase-to-phase insulation of each part of the high-voltage inverter, including the transformer winding, motor winding, and input and output terminals, to obtain the insulation resistance to ground and phase-to-phase insulation resistance of each part, and the average values ​​are calculated respectively. The average values ​​are summed and multiplied by the correction factor coefficient to obtain the insulation resistance of the high-voltage inverter part; the DC resistance of the electrical equipment windings of the high-voltage inverter is measured by a micro-ohmmeter. The electrical equipment windings are specifically the motor windings and the transformer windings. The DC resistance of each electrical equipment is obtained and subtracted from the current threshold set for each electrical equipment to obtain the DC resistance. The absolute value is obtained and summed to obtain the bias value of the high-voltage inverter backup group; the capacitance parameters inside the high-voltage inverter are detected, and the working status of the capacitor is analyzed. The capacitance parameters include capacitance value, leakage current and equivalent series resistance. The high-voltage inverter capacitor is detected by a capacitance meter and an equivalent series resistance meter respectively to obtain the capacitance value and the equivalent series resistance respectively. The rated voltage of the capacitor is applied to the high-voltage inverter capacitor, and the leakage current is obtained by using a microammeter to measure the capacitance. The capacitance value is subtracted from the set capacitance value to obtain the absolute value, and the absolute value is added to the leakage current and the equivalent series resistance to obtain the high-voltage inverter capacitance parameter value.

[0014] Furthermore, the steps for analyzing the dynamic value of the mining high-voltage inverter are as follows: The voltage half-wave deviation value, voltage change deviation value, harmonic distortion value Xb and frequency modulation depth Ts are calculated to obtain the dynamic value Ddz of the mining high-voltage inverter.

[0015] Furthermore, the steps for analyzing the voltage half-wave deviation value and the voltage change deviation value are as follows: The output voltage waveform after modulation of the mining high-voltage inverter is detected by an oscilloscope. With time as the horizontal axis and voltage as the vertical axis, a voltage change curve graph is established over time. The area difference and peak value difference between the positive half-wave and the negative half-wave in each complete waveform are counted, and the surface peak difference of each complete wave is summed up to obtain the voltage half-wave deviation value. A standard voltage change sinusoidal graph is established in the graph. The standard sinusoidal graph and the change graph form a closed area. When the graph is above the standard sinusoidal graph, the closed area formed is a large deviation area. When the graph is below the standard sinusoidal graph, the closed area formed is a small deviation area. The areas of the large deviation area and the small deviation area are counted and summed up to obtain the voltage change deviation value.

[0016] Furthermore, the harmonic distortion value and frequency modulation depth analysis steps are as follows: The modulated output voltage waveform is transformed by Fourier transform to obtain a spectrum with frequency as the horizontal axis and voltage amplitude as the vertical axis. The maximum voltage amplitude value is obtained, and the corresponding frequency is marked as the fundamental frequency. The frequency points higher than 2 times the fundamental frequency are counted, and the voltage amplitude corresponding to each frequency point is marked as Df m , m is the number of the frequency point, the harmonic distortion value Xb is calculated, the maximum frequency and the minimum frequency in the spectrum diagram are obtained, and the frequency modulation depth Ts is obtained by analysis.

[0017] Furthermore, the steps for analyzing the early warning measures corresponding to the high-voltage inverter in different operating states are as follows: The operational value Ytz of the mine-used high-voltage frequency converter is calculated by the formula of the observed abnormal value, the static value and the dynamic value of the mine-used high-voltage frequency converter; when the operational value of the mine-used high-voltage frequency converter is in the comparison reference range TT1, a signal that the high-voltage frequency converter is in good operating condition is issued; when the operational value of the mine-used high-voltage frequency converter is in the comparison reference range TT2, a signal that the high-voltage frequency converter is in poor operating condition is issued, and the system also issues an alarm signal, and the fault indicator light flashes, reminding the maintenance personnel to arrange the inverter maintenance according to the production schedule; when the operational value of the mine-used high-voltage frequency converter is in the comparison reference range TT3, a signal that the high-voltage frequency converter is in poor operating condition is issued, and the system issues a fault indication, the fault indicator light is always on, and an instruction is issued to disconnect the high voltage and prohibit closing, reminding the maintenance personnel to immediately repair the inverter.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention analyzes the component cracks, component burnt states and capacitor bulging states of the high-voltage inverter for mining through the circuit component information and capacitor information of the high-voltage inverter for mining, and obtains the observed abnormal state value of the high-voltage inverter for mining. The resistance, insulation and capacitance parameters of the high-voltage inverter are analyzed through the static information of the high-voltage inverter to obtain the electrostatic value of the high-voltage inverter for mining. The dynamic information of the high-voltage inverter for mining is analyzed for the output voltage of the high-voltage inverter after control to obtain the dynamic electromotive force value of the high-voltage inverter for mining. The present invention can analyze the appearance of important components of the high-voltage inverter, and can also consider the electrical static and electrical dynamic information of the high-voltage inverter, and can identify the operating status of the high-voltage inverter from multiple angles and in depth.

[0019] 2. The present invention receives the observed abnormal state value, the static value and the dynamic value of the high-voltage inverter for mining, and obtains the operating state of the high-voltage inverter for mining based on the analysis, and compares it with the set operating state reference range to obtain the early warning measures corresponding to the high-voltage inverter under different operating states. It can accurately evaluate the high-voltage inverter fault in time and adopt different early warning measures for different fault conditions, thereby reducing the frequency of high-voltage inverter faults and reducing the cost of coal mining for enterprises. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. The following drawings are not intentionally scaled according to the actual sizes, and the focus is on illustrating the main purpose of the present invention.

[0021] Figure 1 It is a system block diagram of the present invention. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work also fall within the scope of protection of the present invention.

[0023] like Figure 1 As shown, a fault detection system for a high-voltage frequency converter for mining includes a server, and the server is connected with a data acquisition module, an appearance module, a static module, a dynamic module and an early warning module.

[0024] The data acquisition module is used to collect circuit element information, capacitance information, static information and dynamic information of the mining high-voltage inverter, and send it to the appearance module, static module and dynamic module.

[0025] The circuit component information and capacitance information of the mining high-voltage inverter are received through the appearance module, and the component cracks, component burnt state and capacitor bulging state of the high-voltage inverter are analyzed accordingly to obtain the abnormal state value of the mining high-voltage inverter. The specific analysis steps are as follows: The analysis steps of component cracking deviation are as follows: Step 1: An industrial camera is set at the high-voltage inverter to obtain an image of the internal circuit components. The component image is grayed and converted into a component grayscale image. The grayscale histogram distribution of the component image is adjusted and the grayscale range is stretched so that the grayscale value of the component in the cracked area can be distinguished from the surrounding normal area. The grayscale image is binarized by setting a threshold through grayscale histogram distribution feature analysis. The cracked area is black and other areas are white. The edge contour of the cracked area is extracted through an edge detection operator to obtain the crack edge contour of the component. Step 2: Obtain the crack edge contour curve of the component and discretize the curve into coordinate points (x i ,y i ), i is the coordinate point number, i=1, 2, 3, ..., I; I is the maximum value of the coordinate point number, according to the formula , the component crack bending energy value Nl is obtained. The larger the component crack bending energy value is, the more complex the shape is; Step 3: Calculate the slope of the crack edge contour curve of the component by using the coordinate difference between each coordinate point and the adjacent point to obtain the tangent direction of each coordinate point of the crack edge contour, and obtain the angle θ between each oblique line direction and the right horizontal line. i , where the value range of the angle is [-π, π]. When the direction of the oblique line is below the right horizontal line and the value is a negative number, the difference between the maximum and minimum values ​​of the angle is counted to obtain the extreme value of the angle. The contour coordinate points are sorted in the order of the coordinate point numbers. The angle in the front is subtracted from the angle in the back, and the absolute value is taken. The sum of the absolute values ​​of the angle differences is counted to obtain the total difference value. The extreme value of the angle and the total difference value are weighted and multiplied by the corresponding weight factor coefficients to obtain the component cracking deviation value. Step 4: Count the number of cracks in the component, the total length of the cracks and the average of the crack width, and sum them to obtain the total length of the cracks in the component. Divide the crack grayscale image into several regions, count the sum of the number of cracks, the length of the cracks and the average of the crack width in each region, and obtain the length of the cracks in each region. Calculate the average crack length. Subtract the average crack length from the length of the cracks in each region and sum the squares to obtain the variance of the crack length of the component. Divide the variance of the crack length of the component by the average crack length to obtain the coefficient of variation of the cracks in the component. Step 5: Mark the component cracking deviation value, component crack total length value and component crack variation coefficient as yp, lc and yb respectively, and normalize them with the component cracking bending energy value Nl according to the set formula , the component crack deviation value YKY is obtained, where f1, f2, f3 and f4 are the set correction factor coefficients of the component crack deviation value, the component crack total length value, the component crack variation coefficient and the component crack bending energy value, respectively, and the specific values ​​are 1.11, 2.11, 312 and 4.12, and e is a natural constant, and its value is 2.718; The internal circuit component image is converted into an HSV image according to the color space conversion algorithm, where H represents hue, S represents saturation, and V represents brightness. The HSV color space reference threshold range WT1 is set. The reference threshold range WT1 is specifically that the brightness value V is less than 0.35 and the saturation S is greater than 0.25 and less than 0.85. When the HSV value in the HSV image is within the color space reference threshold range WT1, the point corresponds to the burnt point, and the HSV values ​​of each point in each HSV image are traversed to obtain the burnt area. The number of pixels in each burnt area is counted and summed up, and divided by the total pixel value to obtain the burnt value of the circuit component, the edge of each burnt area is obtained, and two 3×3 matrices of each edge point in each burnt area are established, specifically the horizontal direction matrix and the vertical matrix , where n is the number of each edge point, 2 represents the hue, saturation or brightness of the edge point adjacent to the non-burned area in the horizontal or vertical direction, 1 represents the hue, saturation or brightness of the edge point in the burned area in the horizontal or vertical direction, and 3 represents the hue, saturation or brightness of the edge point adjacent to the burned area in the horizontal or vertical direction. According to the formula , calculate and obtain the horizontal gradient value STDn and the vertical gradient value CTDn of each edge point, wherein p1, p2, p3, p4, p5, p6, p7, p8, p9, p10, p11 and p12 are all set weight factor coefficients, and the specific values ​​are determined by personnel in this professional field. The horizontal gradient value and the vertical gradient value of each edge point are summed and calculated, and multiplied by the correction factor coefficient to obtain the gradient value of each edge point, which is summed and divided by the number of edge points and multiplied by the correction coefficient t1 to obtain the focal gradient value of each area, and the focal gradient value of each area is greater than the set focal gradient threshold area, and divided by the total number of areas to obtain the circuit component burnout rate; Obtain the original maximum width and maximum length of the capacitor housing, and the width and length of the corresponding position, divide the width of the corresponding position by the original maximum width, divide the length by the original maximum length, and sum them up to obtain the capacitor drum value, normalize the component cracking deviation value, circuit component burn value, circuit component burn out-of-domain rate and capacitor drum value, use the component cracking deviation value as the radius of the circle on the cone, use the circuit component burn value as the radius of the circle below the cone, use the circuit component burn out-of-domain rate as the cone height to construct a cone, use the center of the circle on the cone as the center of the sphere, and use the capacitor drum value as the radius of the sphere to construct a sphere, identify the irregular volume formed by the sphere and the cone, and mark it as the observed abnormal value Gyz of the mining high-voltage inverter; The static information of the high-voltage inverter is received through the static module, and the resistance, insulation and capacitance parameters of the high-voltage inverter are analyzed to obtain the static value of the mining high-voltage inverter. The specific analysis steps are as follows: The insulation resistance meter is used to measure the insulation to ground and phase-to-phase of each part of the high-voltage inverter. The specific parts are the transformer winding, motor winding, and input and output terminals. The insulation resistance to ground and phase-to-phase of each part are obtained, and the average values ​​are calculated respectively. The average values ​​are summed and multiplied by the correction factor coefficient to obtain the absolute group value of the high-voltage inverter part; the DC resistance of the windings of the electrical equipment of the high-voltage inverter is measured by a microohmmeter. The electrical equipment windings are specifically motor windings and transformer windings. The DC resistance of each electrical equipment is obtained, and the absolute value is subtracted from the current threshold set for each electrical equipment. After summing, the bias value of the high-voltage inverter electrical standby group is obtained; the high voltage is detected The capacitor parameters inside the inverter are analyzed for the working state of the capacitor. The capacitor parameters include capacitance value, leakage current and equivalent series resistance. The high-voltage inverter capacitor is tested by a capacitance meter and an equivalent series resistance meter to obtain the capacitance value and equivalent series resistance respectively. The rated voltage of the capacitor is applied to the high-voltage inverter capacitor. The leakage current is obtained by measuring the capacitance with a microammeter. The capacitance value is subtracted from the set capacitance value to obtain the absolute value, and the absolute value is added to the leakage current and equivalent series resistance to obtain the high-voltage inverter capacitance parameter value. The absolute value of the high-voltage inverter part, the bias value of the high-voltage inverter power group and the high-voltage inverter capacitance parameter value are marked as dj, zp and cy respectively. According to the set formula , get the electrostatic value Djz of the high-voltage inverter for mining, where txt1, txt2 and txt3 are the reference weight factor coefficients for the absolute value of the high-voltage inverter part, the bias value of the high-voltage inverter standby group and the parameter value of the high-voltage inverter capacitance, respectively, and λ is the correction factor coefficient, and the specific value is determined by personnel in this professional field; The dynamic module receives the dynamic information of the high-voltage inverter for mining, analyzes the output voltage of the high-voltage inverter after control, and obtains the dynamic value of the high-voltage inverter for mining. The specific analysis is as follows: The output voltage waveform after modulation of the mining high-voltage inverter is detected by an oscilloscope. With time as the horizontal axis and voltage as the vertical axis, a voltage variation curve graph is established with time. The area difference and peak difference between the positive half-wave and the negative half-wave in each complete waveform are counted, and the surface peak difference of each complete wave is obtained by summing up. The voltage half-wave deviation value is obtained by adding up, and a standard voltage change sinusoidal graph is established in the graph. The standard sinusoidal graph and the change graph form a closed area. When the graph is above the standard sinusoidal graph, the closed area formed is a large deviation area. When the graph is below the standard sinusoidal graph, the closed area formed is a small deviation area. The areas of the large deviation area and the small deviation area are counted and summed up to obtain the voltage change deviation value. The modulated output voltage waveform is subjected to Fourier transform to obtain a spectrum graph with frequency as the horizontal axis and voltage amplitude as the vertical axis. The maximum voltage amplitude value is obtained, and the corresponding frequency is marked as the fundamental frequency. The frequency points higher than 2 times the fundamental frequency are counted, and the voltage amplitude corresponding to each frequency point is marked as Df m, m is the number of the frequency point, m=1, 2, ..., M, M is the maximum value of the frequency point number, according to the formula , get the harmonic distortion value Xb, D1 is the voltage amplitude corresponding to the fundamental frequency, get the maximum frequency and minimum frequency in the spectrum diagram, marked as Zd and Zx, according to the set formula Ts= (Zd-Zx) / D2, get the frequency modulation depth Ts, where D2 is the fundamental frequency, mark the voltage half-wave deviation value and voltage change deviation value as Bp and Bb respectively, and normalize them with the harmonic distortion value Xb and the frequency modulation depth Ts, according to the set formula , calculate and obtain the dynamic value Ddz of the mining high-voltage inverter, where g1, g2, g3 and g4 are the set weight factor coefficients of the voltage half-wave deviation value, voltage change deviation value, harmonic distortion value and frequency modulation depth, respectively, and the values ​​are determined by personnel in this professional field, and D3 is the set reference frequency modulation depth; The early warning module is used to receive the observed abnormal value, static value and dynamic value of the high-voltage inverter for mining, and analyze the operating state of the high-voltage inverter for mining, and compare it with the set operating state reference range to obtain the corresponding early warning measures for the high-voltage inverter under different operating states. The specific analysis is as follows: The observed abnormal value Gyz, the electrostatic value Djz and the dynamic value Ddz of the high-voltage inverter for mining are normalized, and the running value Ytz of the high-voltage inverter for mining is obtained according to the set formula Ytz=(h2×Djz+h3×Ddz) / (h1×Gyz), where h1, h2 and h3 are the set influencing factor coefficients of the observed abnormal value, the electrostatic value and the dynamic value of the high-voltage inverter for mining, and the specific values ​​are 1.11, 2.11 and 3.12 respectively; The operation value comparison reference ranges TT1, TT2 and TT3 of the mine-used high-voltage frequency converter are set. When the operation value of the mine-used high-voltage frequency converter is within the comparison reference range TT1, a signal that the high-voltage frequency converter is in good operation state is issued, and no corresponding operation is performed; when the operation value of the mine-used high-voltage frequency converter is within the comparison reference range TT2, a signal that the high-voltage frequency converter is in poor operation state is issued, and the system also issues an alarm signal, and the fault indicator light flashes, to remind maintenance personnel to arrange frequency converter maintenance according to the production schedule; when the operation value of the mine-used high-voltage frequency converter is within the comparison reference range TT3, a signal that the high-voltage frequency converter is in poor operation state is issued, and the system issues a fault indication, the fault indicator light is always on, and an instruction is issued to disconnect the high voltage and prohibit closing, to remind maintenance personnel to immediately perform frequency converter maintenance, wherein the reference range TT1>TT2>TT3.

[0026] The above is an explanation of the present invention and should not be considered as a limitation thereof. Although several exemplary embodiments of the present invention have been described, it will be readily appreciated by those skilled in the art that many modifications may be made to the exemplary embodiments without departing from the novel teachings and advantages of the present invention. Therefore, all such modifications are intended to be included within the scope of the present invention as defined in the claims. It should be understood that the above is an explanation of the present invention and should not be considered as being limited to the specific embodiments disclosed, and modifications to the disclosed embodiments and other embodiments are intended to be included within the scope of the appended claims. The present invention is defined by the claims and their equivalents.

Claims

1. A fault detection system for a high voltage frequency converter for mining, characterized in that: Including servers, server connections are: The data acquisition module is used to collect circuit element information, capacitance information, static information and dynamic information of the mining high-voltage inverter, and send it to the appearance module, static module and dynamic module; The appearance module analyzes the component cracks, component burnt state and capacitor bulging state of the high-voltage inverter through the circuit component information and capacitor information of the mine-used high-voltage inverter, and obtains the abnormal state value of the mine-used high-voltage inverter; The static module analyzes the resistance, insulation and capacitance parameters of the high-voltage inverter through the static information of the high-voltage inverter to obtain the static value of the mining high-voltage inverter; The dynamic module analyzes the output voltage of the high-voltage inverter after the high-voltage inverter is controlled based on the dynamic information of the high-voltage inverter for mining, and obtains the dynamic value of the high-voltage inverter for mining; The early warning module is used to receive the observed abnormal state value, the static value and the dynamic value of the high-voltage inverter for mining, and analyze the operating state of the high-voltage inverter for mining, and compare it with the set operating state reference range to obtain the corresponding early warning measures for the high-voltage inverter under different operating states.

2. A fault detection system for a high-voltage frequency converter for mining according to claim 1, characterized in that: The steps for analyzing the abnormal value of the mining high-voltage inverter are as follows: Get the original maximum width and maximum length of the capacitor housing, and the width and length of the corresponding position, divide the width of the corresponding position by the original maximum width, divide the length by the original maximum length, and sum them up to get the capacitor drum value, normalize the component cracking deviation value, circuit component burnt value, circuit component burnt over-domain rate and capacitor drum value, use the component cracking deviation value as the radius of the circle on the cone, the circuit component burnt value as the radius of the circle below the cone, and the circuit component burnt over-domain rate as the cone height to construct a cone, the center of the circle on the cone is the center of the sphere, and the capacitor drum value is used as the radius of the sphere to construct a sphere, identify the irregular volume formed by the sphere and the cone, and mark it as the observed abnormal value Gyz of the mining high-voltage inverter.

3. A fault detection system for a high-voltage frequency converter for mining according to claim 2, characterized in that: The steps for analyzing the component cracking deviation value are as follows: Step 1: An industrial camera is set at the high-voltage inverter to obtain an image of the internal circuit components, and grayscale processing is performed to convert it into a component grayscale image. The grayscale histogram distribution of the component image is adjusted to stretch the grayscale range. The grayscale image is binarized by setting a threshold through grayscale histogram distribution feature analysis. The cracked area is black and other areas are white. The edge contour of the cracked area is extracted through an edge detection operator to obtain the crack edge contour of the component. Step 2: Obtain the crack edge contour curve of the component and discretize the curve into coordinate points (x i ,y i ), i is the coordinate point number, and the formula is used to calculate the component crack bending energy value Nl; Step 3: Calculate the slope of the coordinate difference between each coordinate point and the adjacent point of the crack edge contour curve of the component to obtain the tangent direction of each coordinate point of the crack edge contour, and obtain the angle between each oblique line direction and the right horizontal line. When the oblique line direction is negative below the right horizontal line, count the difference between the maximum and minimum angles to obtain the extreme value, sort each contour coordinate point in the order of coordinate point numbers, subtract the angle in the front from the angle in the back, and take the absolute value, count the sum of the absolute values ​​of the angle differences to obtain the total difference, perform weighted calculation on the extreme value and the total difference, and multiply them by the corresponding weight factor coefficients to obtain the component crack deviation value; Step 4: Count the number of cracks in the component, the total length of the cracks and the average of the crack width, and sum them to obtain the total length of the cracks in the component. Divide the crack grayscale image into several regions, count the sum of the number of cracks, the length of the cracks and the average of the crack width in each region, and obtain the length of the cracks in each region. Calculate the average crack length. Subtract the average crack length from the length of the cracks in each region and sum the squares to obtain the variance of the crack length of the component. Divide the variance of the crack length of the component by the average crack length to obtain the coefficient of variation of the cracks in the component. Step 5: The component crack deviation value, the total crack length value of the component and the component crack variation coefficient are combined with the component crack bending energy value Nl to calculate the component crack deviation value YKY.

4. A fault detection system for a high-voltage frequency converter for mining according to claim 2, characterized in that: The steps for analyzing the circuit element burnt value and the circuit element burnt out-of-domain rate are as follows: The internal circuit component image is converted into an HSV image according to the color space conversion algorithm, where H represents hue, S represents saturation, and V represents brightness. The HSV color space reference threshold range WT1 is set. The reference threshold range WT1 is that the brightness value V is less than 0.35 and the saturation S is greater than 0.25 and less than 0.

85. When the HSV value in the HSV image is within the color space reference threshold range WT1, the point corresponds to the burnt point, and the HSV values ​​of each point in each HSV image are traversed to obtain the burnt area. The number of pixels in each burnt area is counted, and the sum is divided by the total pixel value to obtain the burnt value of the circuit component. The edges of each burnt area, and two 3×3 matrices of each edge point in each burnt area are established, which are horizontal direction matrix and vertical direction matrix, and the horizontal gradient value STDn of each edge point and the vertical gradient value CTDn of each edge point are calculated, and the horizontal gradient value of each edge point and the vertical gradient value of each edge point are summed and calculated, and multiplied by the correction factor coefficient to obtain the gradient value of each edge point, and the sum is divided by the number of edge points and multiplied by the correction coefficient t1 to obtain the focus gradient value of each area, and the number of areas with focus gradient values ​​greater than the set area focus gradient threshold value of each area is counted, and divided by the total number of areas to obtain the circuit component burnt out-of-domain rate.

5. The fault detection system for a high-voltage frequency converter for mining according to claim 1, characterized in that: The steps for analyzing the electrostatic value of the mining high-voltage inverter are as follows: Mark the absolute value of the high-voltage inverter part, the bias value of the high-voltage inverter power supply group and the high-voltage inverter capacitance parameter value as dj, zp and cy respectively, according to the set formula , and the static value Djz of the high-voltage inverter for mining is obtained, where txt1, txt2 and txt3 are the reference weight factor coefficients for the absolute value of the high-voltage inverter part, the bias value of the high-voltage inverter standby group and the parameter value of the high-voltage inverter capacitance, respectively, and λ is the correction factor coefficient.

6. A fault detection system for a high-voltage frequency converter for mining according to claim 5, characterized in that: The analysis steps of the absolute value of the high-voltage inverter part, the bias value of the high-voltage inverter backup group and the high-voltage inverter capacitor parameter value are as follows: The insulation resistance meter is used to measure the insulation to ground and phase-to-phase insulation of each part of the high-voltage inverter, including the transformer winding, motor winding, and input and output terminals, to obtain the insulation resistance to ground and phase-to-phase insulation resistance of each part, and the average values ​​are calculated respectively. The average values ​​are summed and multiplied by the correction factor coefficient to obtain the insulation resistance of the high-voltage inverter part; the DC resistance of the electrical equipment windings of the high-voltage inverter is measured by a micro-ohmmeter. The electrical equipment windings are specifically the motor windings and the transformer windings. The DC resistance of each electrical equipment is obtained and subtracted from the current threshold set for each electrical equipment to obtain the DC resistance. The absolute value is obtained and summed to obtain the bias value of the high-voltage inverter backup group; the capacitance parameters inside the high-voltage inverter are detected, and the working status of the capacitor is analyzed. The capacitance parameters include capacitance value, leakage current and equivalent series resistance. The high-voltage inverter capacitor is detected by a capacitance meter and an equivalent series resistance meter respectively to obtain the capacitance value and the equivalent series resistance respectively. The rated voltage of the capacitor is applied to the high-voltage inverter capacitor, and the leakage current is obtained by using a microammeter to measure the capacitance. The capacitance value is subtracted from the set capacitance value to obtain the absolute value, and the absolute value is added to the leakage current and the equivalent series resistance to obtain the high-voltage inverter capacitance parameter value.

7. A fault detection system for a high-voltage frequency converter for mining according to claim 1, characterized in that: The steps for analyzing the dynamic value of the mining high-voltage inverter are as follows: The voltage half-wave deviation value, voltage change deviation value, harmonic distortion value Xb and frequency modulation depth Ts are calculated to obtain the dynamic value Ddz of the mining high-voltage inverter.

8. A fault detection system for a high-voltage frequency converter for mining according to claim 7, characterized in that: The steps for analyzing the voltage half-wave deviation value and the voltage change deviation value are as follows: The output voltage waveform after modulation of the mining high-voltage inverter is detected by an oscilloscope. With time as the horizontal axis and voltage as the vertical axis, a voltage change curve graph is established over time. The area difference and peak value difference between the positive half-wave and the negative half-wave in each complete waveform are counted, and the surface peak difference of each complete wave is summed up to obtain the voltage half-wave deviation value. A standard voltage change sinusoidal graph is established in the graph. The standard sinusoidal graph and the change graph form a closed area. When the graph is above the standard sinusoidal graph, the closed area formed is a large deviation area. When the graph is below the standard sinusoidal graph, the closed area formed is a small deviation area. The areas of the large deviation area and the small deviation area are counted and summed up to obtain the voltage change deviation value.

9. A fault detection system for a high-voltage frequency converter for mining according to claim 7, characterized in that: The steps for the harmonic distortion value and frequency modulation depth analysis are as follows: The modulated output voltage waveform is transformed by Fourier transform to obtain a spectrum with frequency as the horizontal axis and voltage amplitude as the vertical axis. The maximum voltage amplitude value is obtained, and the corresponding frequency is marked as the fundamental frequency. The frequency points higher than 2 times the fundamental frequency are counted, and the voltage amplitude corresponding to each frequency point is marked as Df m , m is the number of the frequency point, the harmonic distortion value Xb is calculated, the maximum frequency and the minimum frequency in the spectrum diagram are obtained, and the frequency modulation depth Ts is obtained by analysis.

10. A fault detection system for a high-voltage frequency converter for mining according to claim 1, characterized in that: The analysis steps of the early warning measures corresponding to the high-voltage inverter under different operating conditions are as follows: The operational value Ytz of the mine-used high-voltage frequency converter is calculated by the formula of the observed abnormal value, the static value and the dynamic value of the mine-used high-voltage frequency converter; when the operational value of the mine-used high-voltage frequency converter is in the comparison reference range TT1, a signal that the high-voltage frequency converter is in good operating condition is issued; when the operational value of the mine-used high-voltage frequency converter is in the comparison reference range TT2, a signal that the high-voltage frequency converter is in poor operating condition is issued, and the system also issues an alarm signal, and the fault indicator light flashes, reminding the maintenance personnel to arrange the inverter maintenance according to the production schedule; when the operational value of the mine-used high-voltage frequency converter is in the comparison reference range TT3, a signal that the high-voltage frequency converter is in poor operating condition is issued, and the system issues a fault indication, the fault indicator light is always on, and an instruction is issued to disconnect the high voltage and prohibit closing, reminding the maintenance personnel to immediately repair the inverter.

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