A method and device for detecting insulation faults of a dry-type air-core reactor

Abstract

The application discloses a kind of dry-type hollow reactor's insulation fault detection method and device, comprising the following steps: multiple optical sensors are arranged at the bottom of dry-type hollow reactor, and high-frequency current sensor is worn at the outgoing line end of dry-type hollow reactor;Pulse voltage waveform signal is obtained using signal acquisition component, and pulse voltage waveform signal is transmitted to analysis processing component;Analysis processing component converts pulse voltage waveform signal into photo-electric two-dimensional pulse sequence, and gives photo-electric two-dimensional phase base atlas;Feature parameters in photo-electric two-dimensional phase base atlas are extracted, and photo-electric two-dimensional data set reflecting dry-type hollow reactor fault position information is constructed, as dry-type hollow reactor partial discharge feature, and the positioning of dry-type hollow reactor insulation fault is analyzed and given.The combined detection method of partial discharge based on high-frequency current method and optical detection method is proposed in the application, to realize the accurate positioning of dry-type hollow reactor interturn insulation fault.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electric reactors, and particularly relates to an insulation fault detection method and device for a dry-type air-core electric reactor. BACKGROUND

[0002] The dry-type air-core electric reactor adopts an axisymmetric structure and mainly comprises a plurality of enclosures, upper and lower star-shaped frames, enclosure inter-supporting strips and rainproof caps, etc. The enclosure, star-shaped frame and supporting strip are integrally solidified into one body. The dry-type air-core electric reactor is an electric reactor without a winding-internal iron core relying on air insulation, which is simple in structure, light in weight, low in vibration and noise level, and has been widely applied in power systems at all levels.

[0003] In recent years, there are many dry-type air-core electric reactor burnout failures. The inter-turn insulation material of the electric reactor is mainly a general polyester film and a polyimide film with a higher heat-resistant grade. Partial discharge is a process of developing from the surface to the inside of the medium. Under an external voltage, partial discharge occurs first at the air gap defect of the inter-turn insulation, and the partial discharge destroys the inter-turn insulation to cause breakdown. Due to the large number of enclosures, complex structure and narrow channel, it brings certain obstacles to the overall perception of the state of the dry-type air-core electric reactor.

[0004] At present, the research on the monitoring and analysis of the dry-type air-core electric reactor fault is still limited to the monitoring of a single factor, such as the temperature detection method, the smoke detection method, the insulation detection method, the electrical quantity parameter detection method, the differential detection method, etc. Among them, the research on the insulation detection method is as follows:

[0005] For example, patent CN114062879A gives a dry-type electric reactor inter-turn insulation detection device and method. The insulation detection device comprises: a dry-type electric reactor, a voltage transformer, a current transformer, a power analyzer, a processing system and an alarm system. The dry-type electric reactor is a three-phase dry-type electric reactor. Each phase of the dry-type electric reactor is connected with a group of voltage transformers and current transformers. The three groups of voltage transformers and current transformers are connected with the power analyzer. The processing system judges the working state of the dry-type electric reactor according to the analysis result of the power analyzer. The alarm system is used to alarm the operation and maintenance personnel. The scheme can transmit the voltage and current signals of the dry-type electric reactor running to the power analyzer to calculate the AC impedance in real time without power off. Through horizontal and vertical data comparison of the processing alarm system, the inter-turn insulation state of the dry-type electric reactor is accurately evaluated.

[0006] For example, patent CN104515941A provides a device for detecting inter-turn insulation of a reactor based on the pulse oscillation principle. A high-voltage silicon stack, a protective resistor, and the high and low voltage arm resistors of a resistor divider are connected in series at both ends of the transformer output. A controllable discharge spherical gap and a damped oscillation circuit are connected in parallel across the high and low voltage arm resistors of the resistor divider. The damped oscillation circuit consists of a series-connected damping resistor, a main capacitor, and a reactor test sample. A controller unit controls the discharge of the spherical gap and the transformer output voltage based on the voltage across the high and low voltage arm resistors of the resistor divider. During the spherical gap discharge process, a pulse oscillation is formed on the reactor test sample. The pulse oscillation wave signal formed on the reactor is then transmitted to an oscilloscope via a capacitor divider connected in parallel across the reactor test sample, enabling diagnosis of the reactor's inter-turn insulation. This solution can address the current passive situation of long-term inability to monitor reactor inter-turn insulation and will play a positive role in promoting product quality improvement for reactor manufacturers and ensuring the safe operation of the entire power grid.

[0007] However, the above-mentioned prior arts all have the problem of difficulty in effectively extracting measurement signals due to electromagnetic interference of dry-type air-core reactors when performing insulation fault detection on dry-type air-core reactors, which leads to deviations in fault perception and fault location.

[0008] Therefore, how to achieve accurate fault information perception in the interlayer area of ​​the dry-type hollow reactor to solve the problem of difficulty in obtaining optical signals of partial discharge of dry-type hollow reactors and inaccurate fault information is an urgent problem to be solved by technicians in this field. Summary of the Invention

[0009] In response to the defects in the above-mentioned prior art, the present invention provides a method and device for detecting insulation faults of dry-type air-core reactors. The method and device are provided with an optical sensor and a high-frequency current sensor, and are combined with an optical pulse voltage signal and an electromagnetic pulse voltage signal. The optical-electrical two-dimensional pulse sequence is processed and analyzed to obtain an optical-electrical two-dimensional data set reflecting the fault location information of the dry-type air-core reactor, and the location of the insulation fault of the dry-type air-core reactor is given. In order to realize the perception of fault information in the inter-encapsulation area of ​​the dry-type air-core reactor, the present invention proposes a joint detection method for partial discharge based on high-frequency method and optical detection method. By collecting, processing and analyzing the high-frequency magnetic field signal and ultraviolet day-blind light signal of the inter-turn insulation fault of the dry-type air-core reactor, the problem of the difficulty in obtaining the optical signal of the partial discharge of the dry-type air-core reactor is solved, and the precise location of the insulation fault of the dry-type air-core reactor is realized.

[0010] In a first aspect, the present invention provides a method for detecting insulation faults in dry-type air-core reactors, comprising the following steps:

[0011] A plurality of optical sensors are arranged at the bottom of the dry-type air-core reactor, and a high-frequency current sensor is inserted into the outlet end of the dry-type air-core reactor;

[0012] The signal acquisition component is used to acquire the pulse voltage waveform signal and transmit the pulse voltage waveform signal to the analysis processing component, wherein the pulse voltage waveform signal corresponds to the optical pulse voltage signal sent by the optical sensor and the electromagnetic pulse voltage signal sent by the high-frequency current sensor;

[0013] The analysis processing component converts the pulse voltage waveform signal into an optical-electric two-dimensional pulse sequence and gives an optical-electric two-dimensional phase base map, wherein the optical two-dimensional phase base map and the electric two-dimensional phase base map of the optical-electric two-dimensional phase base map both include a voltage phase-pulse frequency distribution map and a voltage phase-pulse amplitude distribution map;

[0014] The feature parameters in the optical-electric two-dimensional phase base map are extracted, and an optical-electric two-dimensional data set reflecting the fault position information of the dry-type air-core reactor is constructed as the dry-type air-core reactor partial discharge feature, and the positioning of the dry-type air-core reactor insulation fault is analyzed and given.

[0015] Further, the dry-type air-core reactor is provided with a circular ring support, all the optical sensors are carried by the circular ring support, and the photosensitive plane of the optical sensor is perpendicular to the central axis of the dry-type air-core reactor, the response waveband of each optical sensor is 200nm-280nm, and the gain is ≥10 5 ;

[0016] The transmission impedance of the high-frequency current sensor is ≥10Ω, and the electromagnetic signal bandwidth covers the 10MHz-30MHz frequency band.

[0017] Further, corresponding to the shape of the star-shaped frame of the dry-type air-core reactor, the circular ring support is divided into a plurality of arc-shaped regions, and at least one optical sensor is placed in each arc-shaped region.

[0018] Further, the signal acquisition component is connected with the optical sensor and the high-frequency current sensor, and includes a power module, a quenching circuit module, an amplification detection module and a multi-channel acquisition card connected in sequence;

[0019] The power module includes a voltage stabilizing tube and a high-voltage chip, the voltage stabilizing tube provides power for the high-voltage chip, and the high-voltage chip provides a bias voltage for the optical sensor;

[0020] The quenching circuit module includes a first sampling resistor and a second sampling resistor, and the resistance value of the first sampling resistor is greater than that of the second sampling resistor, which is used to output the optical pulse voltage signal when the optical sensor is in avalanche;

[0021] The amplification detection module is used to amplify and demodulate the optical pulse voltage signal;

[0022] The multi-channel acquisition card consists of a multi-channel A / D module, which synchronously collects optical pulse voltage signals and electromagnetic pulse voltage signals and transmits them to the analysis and processing component. The number of channels of the multi-channel A / D module is the sum of the number of all optical sensors and the number of high-frequency current sensors, and each channel synchronously collects the pulse voltage waveform signal.

[0023] Furthermore, the analysis and processing component converts the pulse voltage waveform signal into a two-dimensional optical-electrical pulse sequence and provides a two-dimensional optical-electrical phase-based spectrum, which specifically includes the following steps:

[0024] Sequencing the optical pulse voltage signal and the electromagnetic pulse voltage signal respectively to form an optical pulse sequence and an electromagnetic pulse sequence;

[0025] Normalize the optical pulse sequence and electromagnetic pulse sequence to the range of [-1, 1];

[0026] A normalized optical pulse sequence and a normalized electromagnetic pulse sequence are amplitude-added at the same phase angle;

[0027] Obtain a two-dimensional photoelectric pulse sequence and give a two-dimensional photoelectric phase-based spectrum.

[0028] Furthermore, obtaining a two-dimensional optical-electrical pulse sequence and providing a two-dimensional optical-electrical phase-based spectrum specifically includes the following steps:

[0029] Taking one power frequency cycle of the optical-electrical two-dimensional pulse sequence as a unit of observation time, calculating the summed discharge number information and summed discharge amplitude information in all phase intervals within multiple unit observation times;

[0030] Using the summed discharge number information and the summed discharge amplitude information as data points, the voltage phase-discharge number distribution map and the voltage phase-pulse amplitude distribution map are constructed respectively to obtain the photoelectric two-dimensional phase-based map.

[0031] Furthermore, the characteristic parameters include skewness, kurtosis and starting phase;

[0032] Extracting characteristic parameters from the optical-electrical two-dimensional phase-based spectrum specifically includes the following steps:

[0033] Calculate the third-order central moment of the data points in the optical-electrical two-dimensional phase basis spectrum to obtain the skewness. The specific relationship formula is:

[0034]

[0035] Calculate the normalized fourth-order central moment of the data points in the optical-electrical two-dimensional phase basis spectrum to obtain the kurtosis. The specific relationship formula is:

[0036]

[0037] respectively, as the starting phase;

[0038] wherein, S K is skewness, K u is kurtosis, x i is pulse amplitude, is average pulse amplitude, and σ is standard deviation of pulse amplitude distribution, and n is pulse number.

[0039] Further, the optical-electric two-dimensional data set reflecting the fault position information of the dry-type air-core reactor is constructed, and specifically includes the following steps:

[0040] Based on the voltage phase-pulse number distribution map and the voltage phase-pulse amplitude distribution map, the same type characteristic parameters in the two maps are processed to obtain the average value of the same type characteristic parameters.

[0041] The same type characteristic parameters are taken as sample features to construct the optical-electric two-dimensional data set reflecting the fault position information of the dry-type air-core reactor.

[0042] Wherein, the skewness includes positive half-cycle skewness and negative half-cycle skewness, the kurtosis includes positive half-cycle kurtosis and negative half-cycle kurtosis, and the starting phase includes positive half-cycle starting phase and negative half-cycle starting phase.

[0043] Further, the positioning of the insulation fault of the dry-type air-core reactor is analyzed, and specifically includes the following steps:

[0044] The constructed optical-electric two-dimensional data set is nonlinearly mapped to a high-dimensional space, and the classification plane equation is given through the nonlinear mapping result to give the positioning result of the insulation fault of the air-core reactor.

[0045] The classification plane equation satisfies the following relationship:

[0046]

[0047] Wherein, n is the total number of samples in the optical-electric two-dimensional data set, α i is the Lagrange multiplier of the i th sample, y i is the normalized label value of the i th sample, and k(x,x i ) is the nonlinear mapping.

[0048] The nonlinear mapping satisfies the following relationship:

[0049] k(x,x i )=exp(-γ‖x-x i ‖ 2 )

[0050] Among them, γ is the mapping parameter, whose value is the inverse of the number of sample features, x is the feature vector of all samples in the data set, x i is the feature vector of the i-th sample in the dataset.

[0051] In a second aspect, the present invention further provides an insulation fault detection device for a dry-type air-core reactor, which adopts the above-mentioned insulation fault detection method for a dry-type air-core reactor, comprising: a monitoring component, a signal acquisition component, and an analysis and processing component; wherein the monitoring component comprises: a plurality of optical sensors arranged at the bottom of the dry-type air-core reactor and a high-frequency current sensor sleeved on the outlet end of the dry-type air-core reactor;

[0052] A signal acquisition component acquires a pulse voltage waveform signal and transmits the pulse voltage waveform signal to an analysis and processing component;

[0053] The analysis and processing component converts the pulse voltage waveform signal into a two-dimensional optical-electric pulse sequence, and gives a two-dimensional optical-electric phase-based map. The characteristic parameters in the two-dimensional optical-electric phase-based map are extracted, and a two-dimensional optical-electric dataset reflecting the fault location information of the dry-type air-core reactor is constructed as the partial discharge feature of the dry-type air-core reactor. The analysis gives the location of the insulation fault of the dry-type air-core reactor.

[0054] The present invention provides a method and device for detecting insulation faults in dry-type air-core reactors, which have at least the following beneficial effects:

[0055] (1) In order to realize the fault information perception of the inter-layer area of ​​the dry-type air-core reactor, a joint detection method of partial discharge based on high-frequency method and optical detection method is proposed. By collecting, processing and analyzing the high-frequency magnetic field signal and ultraviolet day-blind light signal of the inter-turn insulation fault of the dry-type air-core reactor, the problem of the difficulty in obtaining the optical signal of the partial discharge of the dry-type air-core reactor is solved, and the precise positioning of the insulation fault of the dry-type air-core reactor is achieved.

[0056] (2) The signal acquisition component and analysis and processing component in the present invention can simultaneously realize timing analysis based on electromagnetic fault signals and optical fault signals, thereby improving the accuracy of fault signal acquisition, processing and analysis.

[0057] (3) A two-dimensional time domain feature extraction method for optical pulse signals and high-frequency electromagnetic pulse signals was designed to solve the problem of lack of local discharge classification features and achieve better fault location results. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 A schematic flow chart of a method for detecting insulation faults in a dry-type air-core reactor provided by the present invention;

[0059] Figure 2 A schematic diagram of the arrangement structure of an optical sensor according to an embodiment of the present invention;

[0060] Figure 3 A schematic structural diagram of a signal acquisition component according to an embodiment of the present invention;

[0061] Figure 4 The present invention provides a schematic structural diagram of an insulation fault detection device for a dry-type air-core reactor.

[0062] Description of reference numerals:

[0063] 1-optical sensor, 2-ring bracket, 3-star frame, 4-encapsulation layer, 5-air gap layer. DETAILED DESCRIPTION

[0064] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0065] The terms used in the embodiments of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The singular forms "a," "an," "the," and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, and unless the context clearly indicates otherwise, "a plurality" generally includes at least two.

[0066] It should also be noted that the terms "include," "comprises," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a product or device comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such product or device. In the absence of further limitations, an element defined by the phrase "comprises a..." does not exclude the presence of other identical elements in the product or device comprising the element.

[0067] In order to realize the fault information perception of the inter-layer area of ​​dry-type air-core reactors, a joint partial discharge detection method based on high-frequency method and optical detection method is proposed. By collecting, processing and analyzing the high-frequency magnetic field signal and ultraviolet day-blind light signal of the inter-turn insulation fault of the dry-type air-core reactor, the problem of difficulty in obtaining the optical signal of the partial discharge of the dry-type air-core reactor is solved, and the insulation fault of the dry-type air-core reactor is accurately located.

[0068] like Figure 1 As shown, the present invention provides a method for detecting insulation faults of dry-type air-core reactors, comprising the following steps:

[0069] A plurality of optical sensors are arranged at the bottom of the dry-type air-core reactor, and a high-frequency current sensor is inserted into the outlet end of the dry-type air-core reactor;

[0070] A signal acquisition component is used to acquire a pulse voltage waveform signal, and the pulse voltage waveform signal is transmitted to an analysis and processing component, wherein the pulse voltage waveform signal corresponds to the light pulse voltage signal sent by the optical sensor and the electromagnetic pulse voltage signal sent by the high-frequency current sensor;

[0071] The analysis and processing component converts the pulse voltage waveform signal into a two-dimensional optical-electrical pulse sequence and generates a two-dimensional optical-electrical phase-basis map. Both the optical two-dimensional phase-basis map and the electrical two-dimensional phase-basis map of the two-dimensional optical-electrical phase-basis map include a voltage phase-pulse number distribution map and a voltage phase-pulse amplitude distribution map.

[0072] The characteristic parameters in the optical-electrical two-dimensional phase-based map are extracted, and an optical-electrical two-dimensional dataset reflecting the fault location information of the dry-type air-core reactor is constructed. These parameters are used as the partial discharge characteristics of the dry-type air-core reactor, and the insulation fault location of the dry-type air-core reactor is analyzed and given.

[0073] Among them, the optical-electrical two-dimensional pulse sequence is the two-dimensional pulse sequence of optical pulse voltage signal-electromagnetic pulse voltage signal, and the optical-electrical two-dimensional phase-based spectrum is the two-dimensional phase-based spectrum of optical pulse signal-electromagnetic pulse signal.

[0074] The signal acquisition component and analysis and processing component can simultaneously realize timing analysis based on electromagnetic fault signals and optical fault signals, thereby improving the accuracy of fault signal acquisition, processing and analysis.

[0075] like Figure 2 As shown, the dry-type air-core reactor includes an encapsulation layer 4, an air gap layer 5 and a star frame 3. A circular bracket 2 is set at the bottom of the dry-type air-core reactor. All optical sensors 1 are supported by the circular bracket 2, and the photosensitive plane of the optical sensor 1 is perpendicular to the central axis of the dry-type air-core reactor. The response band of each optical sensor 1 is 200nm-280nm, and the gain is ≥10 5 ;

[0076] The transmission impedance of the high-frequency current sensor is ≥10Ω, and the electromagnetic signal bandwidth covers the frequency band of 10MHz-30MHz.

[0077] Corresponding to the shape of the dry-type air-core reactor star frame 3, the annular support 2 is divided into a plurality of arc-shaped areas, and at least one optical sensor 1 is placed in each arc-shaped area.

[0078] Optical sensor 1 can use SiC-based ultraviolet solar-blind photodetector (SiC APD). The function of SiC APD is to receive and transmit the ultraviolet solar-blind band fault light signal emitted by the dry-type air-core reactor fault source. Its response band should cover 200nm-280nm, and the gain should be higher than 10 5 The optical sensor 1 is based on the annular bracket 2. The optical sensor 1 is composed of 6 identical SiC APDs, which are evenly arranged at the bottom of the dry-type air-core reactor. It receives the light radiated outward from the insulation faults at different spatial locations and converts it into optical pulse signals.

[0079] The high-frequency current sensor (not shown) inserted into the dry-type air-core reactor's outlet can use a Rogowski coil. This couples the high-frequency magnetic field signal induced by the discharge pulse current and converts it into an electrical pulse signal. Its transmission impedance should be greater than 10Ω, and the electromagnetic pulse signal bandwidth should cover the 10MHz-30MHz frequency range. The power supply uses a 220V industrial frequency power supply, which is boosted by an auto-voltage regulator and transformer before acting on the dry-type air-core reactor. The industrial frequency voltage signal is then extracted through the low-voltage arm of a capacitive voltage divider to the acquisition terminal to obtain discharge phase information.

[0080] like Figure 3 As shown, the signal acquisition component is connected to the optical sensor and the high-frequency current sensor, and includes a power supply module, a quenching circuit module, an amplification and detection module, and a multi-channel acquisition card connected in sequence;

[0081] The power module includes a voltage regulator tube and a high-voltage chip. The voltage regulator tube provides power for the high-voltage chip, and the high-voltage chip provides bias voltage for the optical sensor.

[0082] The quenching circuit module includes a first sampling resistor and a second sampling resistor, wherein the resistance of the first sampling resistor is greater than that of the second sampling resistor, and is used to output a light pulse voltage signal when the optical sensor avalanches;

[0083] The amplification and detection module is used to gain and demodulate the optical pulse voltage signal;

[0084] The multi-channel acquisition card consists of a multi-channel A / D module, which synchronously collects optical pulse voltage signals and electromagnetic pulse voltage signals and transmits them to the analysis and processing component. The number of channels of the multi-channel A / D module is the sum of the number of all optical sensors and the number of high-frequency current sensors, and each channel synchronously collects the pulse voltage waveform signal.

[0085] The analysis and processing component converts the pulse voltage waveform signal into a two-dimensional optical-electrical pulse sequence and provides a two-dimensional optical-electrical phase-based spectrum. The specific steps include:

[0086] Sequencing the optical pulse voltage signal and the electromagnetic pulse voltage signal respectively to form an optical pulse sequence and an electromagnetic pulse sequence;

[0087] The optical pulse sequence and the electromagnetic pulse sequence are normalized, and the normalized interval is [-1, 1];

[0088] The normalized optical pulse sequence and the normalized electromagnetic pulse sequence are added in amplitude at the same phase angle;

[0089] An optical-electric two-dimensional pulse sequence is obtained, and an optical-electric two-dimensional phase base atlas is given.

[0090] Further, an optical-electric two-dimensional pulse sequence is obtained, and an optical-electric two-dimensional phase base atlas is given, specifically including the following steps:

[0091] In a unit of time, the discharge frequency information and the discharge amplitude information added in all phase intervals in a plurality of units of time are calculated;

[0092] The discharge frequency information and the discharge amplitude information added are taken as data points, and a voltage phase-discharge frequency distribution atlas and a voltage phase-pulse amplitude distribution atlas are constructed respectively to obtain the optical-electric two-dimensional phase base atlas.

[0093] The characteristic parameters include skewness, kurtosis and initial phase;

[0094] The characteristic parameters in the optical-electric two-dimensional phase base atlas are extracted, specifically including the following steps:

[0095] The third central moment of the data points in the optical-electric two-dimensional phase base atlas is calculated to obtain the skewness, and the specific relationship formula is:

[0096]

[0097] The normalized fourth central moment of the data points in the optical-electric two-dimensional phase base atlas is calculated to obtain the kurtosis, and the specific relationship formula is:

[0098]

[0099] The phases at which the discharge starts in the positive half cycle and the negative half cycle of the optical-electric two-dimensional phase base atlas are obtained respectively as the initial phase;

[0100] Wherein, S K is the skewness, K u is the kurtosis, x i is the pulse amplitude, is the average pulse amplitude, σ is the standard deviation of the pulse amplitude distribution atlas, and n is the pulse frequency.

[0101] An optical-electric two-dimensional data set reflecting the fault position information of the dry-type air-core reactor is constructed, specifically including the following steps:

[0102] Based on the voltage phase-pulse number distribution map and the voltage phase-pulse amplitude distribution map, the same type characteristic parameters in the two parts of the map are processed to obtain the average value of the same type characteristic parameters.

[0103] The same type characteristic parameters are taken as sample features to construct an optical-electric two-dimensional data set reflecting the fault position information of the dry-type air-core reactor.

[0104] The skewness includes positive half-cycle skewness and negative half-cycle skewness, the kurtosis includes positive half-cycle kurtosis and negative half-cycle kurtosis, and the initial phase includes positive half-cycle initial phase and negative half-cycle initial phase.

[0105] The optical pulse signal-high frequency electromagnetic pulse signal two-dimensional time domain feature extraction method solves the problem of lack of partial discharge classification features and achieves good fault positioning effect.

[0106] The positioning of the dry-type air-core reactor insulation fault is analyzed and includes the following steps:

[0107] The constructed optical-electric two-dimensional data set is nonlinearly mapped to a high-dimensional space, and the classification plane equation is given by the nonlinear mapping result to give the positioning result of the air-core reactor insulation fault.

[0108] The classification plane equation satisfies the following relationship:

[0109]

[0110] Where n is the total number of samples in the optical-electric two-dimensional data set, and i is the Lagrange multiplier of the i th sample, y i is the normalized label value of the i th sample, and k(x,x i ) is a nonlinear mapping.

[0111] The nonlinear mapping satisfies the following relationship:

[0112] k(x,x i )=exp(-γ‖x-x i ‖ 2 )

[0113] Where γ is a mapping parameter, x is a feature vector of all samples in the data set, and x i is a feature vector of the i th sample in the data set.

[0114] A fingerprint library containing dry-type air-core reactor fault position information is constructed under laboratory conditions. The trained analysis and processing component is applied to the dry-type air-core reactor simulation experiment platform, and the results show that it has accurate fault recognition and positioning error can be controlled within 10 cm.

[0115] In a second aspect, the present application provides an insulation fault detection device for a dry-type air-core reactor, which adopts the insulation fault detection method for a dry-type air-core reactor as described above, and comprises a monitoring component, a signal acquisition component and an analysis processing component; wherein the monitoring component comprises a plurality of optical sensors arranged at the bottom of the dry-type air-core reactor and a high-frequency current sensor sleeved on the outgoing line end of the dry-type air-core reactor;

[0116] The signal acquisition component acquires the pulse voltage waveform signal and transmits the pulse voltage waveform signal to the analysis processing component;

[0117] The analysis processing component converts the pulse voltage waveform signal into a photo-electric two-dimensional pulse sequence, gives a photo-electric two-dimensional phase base map, extracts a characteristic parameter in the photo-electric two-dimensional phase base map, constructs a photo-electric two-dimensional data set reflecting the fault position information of the dry-type air-core reactor as a dry-type air-core reactor partial discharge feature, and analyzes to give the positioning of the insulation fault of the dry-type air-core reactor.

[0118] Although preferred embodiments of the present application have been described, those skilled in the art, once aware of the basic inventive concept, can make additional changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application. Obviously, those skilled in the art can make various modifications and changes to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and changes of the present application fall within the scope of the claims of the present application and their equivalents, the present application also intends to include these modifications and changes.

Claims

1. A method for detecting insulation faults of dry-type air-core reactors, characterized in that: The steps include: A plurality of optical sensors are arranged at the bottom of the dry-type air-core reactor, and a high-frequency current sensor is inserted into the outlet end of the dry-type air-core reactor; A signal acquisition component is used to acquire a pulse voltage waveform signal, and the pulse voltage waveform signal is transmitted to an analysis and processing component, wherein the pulse voltage waveform signal corresponds to the light pulse voltage signal sent by the optical sensor and the electromagnetic pulse voltage signal sent by the high-frequency current sensor; The analysis and processing component converts the pulse voltage waveform signal into a two-dimensional optical-electrical pulse sequence and generates a two-dimensional optical-electrical phase-basis map. Both the optical two-dimensional phase-basis map and the electrical two-dimensional phase-basis map of the two-dimensional optical-electrical phase-basis map include a voltage phase-pulse number distribution map and a voltage phase-pulse amplitude distribution map. The characteristic parameters in the optical-electrical two-dimensional phase-based map are extracted, and an optical-electrical two-dimensional dataset reflecting the fault location information of the dry-type air-core reactor is constructed. These parameters are used as the partial discharge characteristics of the dry-type air-core reactor, and the insulation fault location of the dry-type air-core reactor is analyzed and given.

2. The insulation fault detection method for a dry-type air-core reactor according to claim 1, wherein: A circular bracket is set at the bottom of the dry-type air-core reactor. All optical sensors are supported by the circular bracket, and the photosensitive plane of the optical sensor is perpendicular to the central axis of the dry-type air-core reactor. The response band of each optical sensor is 200nm-280nm, and the gain is ≥10 5 ; The transmission impedance of the high-frequency current sensor is ≥10Ω, and the electromagnetic signal bandwidth covers the frequency band of 10MHz-30MHz.

3. The insulation fault detection method for a dry-type air-core reactor according to claim 2, wherein: Corresponding to the shape of the dry-type air-core reactor star frame, the annular bracket is divided into multiple arc-shaped areas, and at least one optical sensor is placed in each arc-shaped area.

4. The method for detecting insulation fault of a dry-type air-core reactor according to any one of claims 1 to 3, characterized in that: The signal acquisition component is connected to the optical sensor and the high-frequency current sensor, and includes a power supply module, a quenching circuit module, an amplification and detection module, and a multi-channel acquisition card connected in sequence; The power module includes a voltage regulator tube and a high-voltage chip. The voltage regulator tube provides power for the high-voltage chip, and the high-voltage chip provides bias voltage for the optical sensor. The quenching circuit module includes a first sampling resistor and a second sampling resistor, wherein the resistance of the first sampling resistor is greater than that of the second sampling resistor, and is used to output a light pulse voltage signal when the optical sensor avalanches; The amplification and detection module is used to gain and demodulate the optical pulse voltage signal; The multi-channel acquisition card consists of a multi-channel A / D module, which synchronously collects optical pulse voltage signals and electromagnetic pulse voltage signals and transmits them to the analysis and processing component. The number of channels of the multi-channel A / D module is the sum of the number of all optical sensors and the number of high-frequency current sensors, and each channel synchronously collects the pulse voltage waveform signal.

5. The insulation fault detection method for a dry-type air-core reactor according to claim 1, wherein: The analysis and processing component converts the pulse voltage waveform signal into a two-dimensional optical-electrical pulse sequence and provides a two-dimensional optical-electrical phase-based spectrum. The specific steps include: Sequencing the optical pulse voltage signal and the electromagnetic pulse voltage signal respectively to form an optical pulse sequence and an electromagnetic pulse sequence; Normalize the optical pulse sequence and electromagnetic pulse sequence to the range of [-1, 1]; A normalized optical pulse sequence and a normalized electromagnetic pulse sequence are amplitude-added at the same phase angle; Obtain a two-dimensional photoelectric pulse sequence and give a two-dimensional photoelectric phase-based spectrum.

6. The insulation fault detection method for a dry-type air-core reactor according to claim 5, characterized in that: Obtaining a two-dimensional photoelectric pulse sequence and providing a two-dimensional photoelectric phase-based spectrum includes the following steps: Taking one power frequency cycle of the optical-electrical two-dimensional pulse sequence as a unit of observation time, calculating the summed discharge number information and summed discharge amplitude information in all phase intervals within multiple unit observation times; Using the summed discharge number information and the summed discharge amplitude information as data points, the voltage phase-discharge number distribution map and the voltage phase-pulse amplitude distribution map are constructed respectively to obtain the photoelectric two-dimensional phase-based map.

7. The insulation fault detection method for a dry-type air-core reactor according to claim 1, wherein: Characteristic parameters include skewness, kurtosis and starting phase; Extracting characteristic parameters from the optical-electrical two-dimensional phase-based spectrum specifically includes the following steps: Calculate the third-order central moment of the data points in the optical-electrical two-dimensional phase basis spectrum to obtain the skewness. The specific relationship formula is: Calculate the normalized fourth-order central moment of the data points in the optical-electrical two-dimensional phase basis spectrum to obtain the kurtosis. The specific relationship formula is: The phases at which discharge begins in the positive half cycle and the negative half cycle of the photoelectric two-dimensional phase-based spectrum are obtained as the starting phases; Among them, S K is the skewness, K u is the kurtosis, x i is the pulse amplitude, is the average pulse amplitude, σ is the standard deviation of the pulse amplitude distribution spectrum, and n is the number of pulses.

8. The method for detecting insulation fault of a dry-type air-core reactor according to claim 7, wherein: Constructing an optical-electrical two-dimensional dataset reflecting the fault location information of dry-type air-core reactors includes the following steps: Based on the voltage phase-pulse number distribution map and the voltage phase-pulse amplitude distribution map, the same type of characteristic parameters in the two parts of the map are processed to obtain the average value of the same type of characteristic parameters; Using the same type of characteristic parameters as sample features, an optical-electrical two-dimensional dataset reflecting the fault location information of dry-type air-core reactors is constructed. The skewness includes the positive half-cycle skewness and the negative half-cycle skewness, the kurtosis includes the positive half-cycle kurtosis and the negative half-cycle kurtosis, and the starting phase includes the positive half-cycle starting phase and the negative half-cycle starting phase.

9. The method for detecting insulation fault of a dry-type air-core reactor according to claim 8, wherein: The analysis provides the location of the insulation fault of the dry-type air-core reactor, which includes the following steps: The constructed optical-electrical two-dimensional data set is nonlinearly mapped to a high-dimensional space. The classification plane equation is derived from the nonlinear mapping result, and the insulation fault location result of the air-core reactor is obtained. The classified plane equations satisfy the following relationship: Where n is the total number of samples in the optical-electrical two-dimensional dataset, α i is the Lagrange multiplier of the i-th sample, y i is the normalized label value of the i-th sample, k(x,x i ) is a nonlinear mapping; Nonlinear mapping satisfies the following relationship: k(x,x i )=exp(-γ||x-x i || 2 ) Among them, γ is the mapping parameter, x is the feature vector of all samples in the data set, and x i is the feature vector of the i-th sample in the dataset.

10. An insulation fault detection device for a dry-type air-core reactor, characterized in that: The insulation fault detection method of a dry-type air-core reactor according to any one of claims 1 to 9 comprises: a monitoring component, a signal acquisition component, and an analysis and processing component; wherein the monitoring component comprises: a plurality of optical sensors arranged at the bottom of the dry-type air-core reactor and a high-frequency current sensor sleeved on the outlet end of the dry-type air-core reactor; A signal acquisition component acquires a pulse voltage waveform signal and transmits the pulse voltage waveform signal to an analysis and processing component; The analysis and processing component converts the pulse voltage waveform signal into a two-dimensional optical-electric pulse sequence, and gives a two-dimensional optical-electric phase-based map. The characteristic parameters in the two-dimensional optical-electric phase-based map are extracted, and a two-dimensional optical-electric dataset reflecting the fault location information of the dry-type air-core reactor is constructed as the partial discharge feature of the dry-type air-core reactor. The analysis gives the location of the insulation fault of the dry-type air-core reactor.

Images