Local discharge source space positioning system based on transformer

Abstract

The invention discloses a partial discharge source space positioning system based on a transformer, and belongs to the technical field of power equipment state monitoring. The transformer-based partial discharge source space positioning system comprises a data statistics center, and the input end of the data statistics center is connected with the output ends of an acoustic detection module, an environment detection module, a polarity detection module and a component detection module. The system solves the problem that in the actual use process of an existing positioning system, the position detection effect of a branch circuit cannot be ensured, and the detection work quality is affected, four ultrasonic sensors are adopted for detecting the arrival sequence of sound wave information transmitted by ultrasonic waves on transformer oil and a container wall, and the detection accuracy is improved. Positioning calculation is combined path calculation based on ultrasonic signals, according to summarized phenomena generated in the partial discharge process of the power transformer, the partial discharge position can be quickly found out when a fault occurs, the local positioning effect is improved, and long-term use is facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of power equipment status monitoring, in particular to a transformer partial discharge source spatial positioning system. Background Art

[0002] Gas turbine generator sets are power generation devices consisting of gas turbines and generators. Compared with steam turbine generator sets, this type of unit has a simpler structure and fewer auxiliary equipment, so the investment, land occupation and power generation costs are lower than the former. Its insulation reliability affects the stable and safe operation of the power grid. Partial discharge is a tiny discharge caused by excessive field strength at the internal defects of the insulation of electrical equipment, which will accelerate the insulation degradation of the transformer and seriously affect the safe operation of the transformer.

[0003] The Chinese patent with announcement number CN118330411A discloses a system, method and device for spatial positioning of partial discharge sources of transformers. The signals of multiple ultra-high frequency sensors are distributed through high-speed switching switches, and only two-channel acquisition cards are used for data acquisition. After being processed by the signal conditioning circuit, the small window cross-correlation accumulation algorithm is used on the software side to calculate the signal arrival time difference between the reference sensor and other sensors, and the optimization objective function considering the non-line-of-sight error for path correction is substituted into it. The fireworks algorithm with gravity operator is used to calculate the position of the discharge source. The acquisition card hardware comprehensively considers the signal sampling accuracy and hardware cost, improves the accuracy of delay estimation and the global optimization ability of the algorithm in the positioning software algorithm, and considers the impact of non-line-of-sight propagation errors and the number of sensors based on TDOA positioning. The positioning accuracy is greatly improved by correcting the signal propagation path and increasing the number of sensors.

[0004] The positioning system of the above patent cannot ensure the detection effect of the branch circuit position during actual use, which affects the quality of the detection work; therefore, it does not meet the existing needs. In this regard, we propose a spatial positioning system based on the transformer local discharge source. Summary of the invention

[0005] The purpose of the present invention is to provide a spatial positioning system based on a transformer partial discharge source, which solves the problem that the positioning system proposed in the above background technology cannot ensure the circuit position detection effect of the branch during actual use, affecting the quality of the detection work.

[0006] To achieve the above object, the present invention provides the following technical solution: a system for spatially locating a transformer partial discharge source includes a data statistics center, wherein an input end of the data statistics center is connected to output ends of an acoustic detection module, an environmental detection module, a polarity detection module, and a component detection module;

[0007] The acoustic detection module is used for:

[0008] Detect the sound produced by currents of the same magnitude;

[0009] The environment detection module is used for:

[0010] Use multi-module environmental sensors to detect the environment around the transformer;

[0011] The polarity detection module is used for:

[0012] After each insulation test is completed, test the polarity of the current transformer, using the ratio difference for detection. Check that the wiring of the ratio difference is the same as that of the transformation ratio.

[0013] The ratio difference refers to the difference between the secondary current converted to the primary according to the current ratio and the actual secondary current;

[0014] The component detection module is used for:

[0015] The DC bias voltage is extracted, and the obtained DC component is adjusted by the control system to obtain the DC feedback quantity. After being superimposed on the fundamental wave, the DC component is adjusted by the dual closed-loop system of voltage and current. The detection circuit is verified by a 10KVA inverter experimental platform.

[0016] Preferably, the data statistics center includes:

[0017] Data processing module for:

[0018] The collected load data of the discharge monitoring device is compared and judged with historical data, and then the data that meets the current change amplitude judgment is marked through the current analysis module.

[0019] Preferably, the output end of the data statistics center is connected to the input ends of the alarm module, the storage module and the analysis module;

[0020] The alarm module comprises:

[0021] Speaker and warning light for:

[0022] Analyze the collected statistical data and determine the error value. When the error value exceeds the specified value, turn on the speaker and alarm light to sound the alarm.

[0023] Also included is a wireless transmission module for:

[0024] Send the collected statistical data and error values ​​to the remote terminal.

[0025] Preferably, the storage module is used for:

[0026] The STC89C58 microcontroller controls the SD card to store large amounts of data and collect statistical current data.

[0027] The analysis module is used to:

[0028] By introducing artificial intelligence and machine learning technologies, intelligent data analysis and decision support are provided, and the analysis module includes automated data preprocessing, intelligent data analysis and modeling, and intelligent recommendation and prediction functions.

[0029] Preferably, the input end of the acoustic detection module is connected to the output end of the bass wave signal sensing unit, the noise detection unit and the sound wave movement detection unit, and the input end of the bass wave signal sensing unit, the noise detection unit and the sound wave movement detection unit is connected to the output end of the ultrasonic emission unit;

[0030] The ultrasonic sensor is used for:

[0031] Detect the ultrasonic waves generated by partial discharge in transformers. Four ultrasonic sensors are used to detect the arrival order of the sound wave information propagating in transformer oil and container walls.

[0032] The acoustic detection module further includes:

[0033] Mobile sensors are used to avoid shunting and provide a clear location of the acoustic signal.

[0034] Preferably, the polarity detection module includes a tested current transformer and a standard current transformer, and the output ends of the tested current transformer and the standard current transformer are both connected to the input end of the data comparison module;

[0035] The data comparison module refers to the calculation of the difference between the secondary current converted to the primary current according to the current ratio and the actual secondary current, and the wiring for checking the difference is the same as the wiring for checking the transformation ratio;

[0036] When the transformation ratio of the standard current transformer is the same as the transformation ratio of the current transformer under test, the current ratio error is the same as the current ratio difference.

[0037] Preferably, the component detection module includes a low-pass filter, an isolation follower unit and a conditioning amplifier unit, and the output ends of the low-pass filter, the isolation follower unit and the conditioning amplifier unit are all connected to the input end of the voltage extraction module;

[0038] The voltage extraction module is used to extract the voltage of the detection circuit.

[0039] Preferably, the component detection module is composed of a hardware circuit of low-pass filtering, isolation following, and conditioning amplification, and extracts the DC bias voltage. The obtained DC component is adjusted by the PLC module to obtain a DC feedback amount, and after being superimposed on the fundamental wave, the DC component is adjusted by a dual closed-loop system of voltage and current for suppressing the DC bias voltage.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] 1. The acoustic detection module of the present invention is applied inside a transformer. The partial discharge phenomenon of the transformer will generate ultrasonic waves, which are then propagated on the transformer oil and the container wall. The ultrasonic waves generated by the partial discharge phenomenon of the transformer are detected. Four ultrasonic sensors are used to detect the arrival order of the sound wave information propagated on the transformer oil and the container wall. The positioning calculation is based on the combined path calculation of the ultrasonic signal. According to the phenomena accompanying the partial discharge process of the power transformer, combined with the actual application situation, a specific method is used for detection. In the actual use process, the partial discharge position can be quickly found out when a fault occurs, thereby improving the local positioning effect and facilitating long-term use.

[0042] 2. The polarity detection module of the present invention tests the polarity of the current transformer after various insulation tests are completed, and uses the ratio difference for detection. The wiring for checking the ratio difference is the same as the wiring for checking the transformation ratio. The ratio difference and phase difference must be measured for the current transformer after the winding is replaced. In order to ensure the correctness of the power element and the impedance element, as well as the differential protection, the component detection module, the acoustic detection module and the environmental detection module are cooperated to fully detect the data information to improve the detection accuracy.

[0043] 3. The present invention extracts the DC bias voltage, and the obtained DC component is adjusted by the control system to obtain the DC feedback amount, which is superimposed on the fundamental wave, and then the DC component is adjusted by the dual closed-loop system of voltage and current. The detection circuit is verified by a 10KVA inverter experimental platform. The detection circuit is composed of a hardware circuit of low-pass filtering, isolation following, and conditioning and amplification. The DC bias voltage is extracted, and the obtained DC component is adjusted by the PLC module to obtain the DC feedback amount, which is superimposed on the fundamental wave, and then the DC component is adjusted by the dual closed-loop system of voltage and current for suppressing the DC bias voltage. The suppression effect of the DC bias voltage is significantly better than that of the commonly used detection circuits and suppression measures, and can obtain an ideal suppression effect under strong electromagnetic interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a system principle block diagram of the present invention;

[0045] Figure 2 is a principle block diagram of the acoustic detection module of the present invention;

[0046] Figure 3 is a principle block diagram of the polarity detection module of the present invention;

[0047] Figure 4 It is a principle block diagram of the component detection module of the present invention. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] In order to solve the problem that the existing positioning system cannot ensure the detection effect of the branch circuit position in actual use, which affects the quality of detection work, please refer to Figure 1 - Figure 2 , this embodiment provides the following technical solutions:

[0050] A spatial positioning system based on a transformer partial discharge source includes a data statistics center, wherein an input end of the data statistics center is connected to output ends of an acoustic detection module, an environmental detection module, a polarity detection module, and a component detection module;

[0051] Acoustic detection module for:

[0052] Detect the sound emitted by currents of the same magnitude, and use specific methods to detect it in combination with the actual application situation. In the actual use process, when a fault occurs, the local discharge position can be quickly found, which improves the local positioning effect and is conducive to long-term use. Cooperate with the component detection module, polarity detection module and environment detection module to fully detect the data information and improve the detection accuracy;

[0053] Environmental detection module for:

[0054] Use multi-module environmental sensors to detect the environment around the transformer;

[0055] Polarity detection module for:

[0056] After each insulation test is completed, test the polarity of the current transformer, using the ratio difference for detection. Check that the wiring of the ratio difference is the same as that of the transformation ratio.

[0057] The ratio difference refers to the difference between the secondary current converted to the primary according to the current ratio and the actual secondary current;

[0058] The component detection module is used to:

[0059] The DC bias voltage is extracted, and the obtained DC component is adjusted by the control system to obtain the DC feedback quantity. After being superimposed on the fundamental wave, the DC component is adjusted by the dual closed-loop system of voltage and current. The detection circuit is verified by a 10KVA inverter experimental platform.

[0060] In this embodiment, the input end of the acoustic detection module is connected to the output end of the bass wave signal sensing unit, the noise detection unit and the sound wave movement detection unit, and the input end of the bass wave signal sensing unit, the noise detection unit and the sound wave movement detection unit is connected to the output end of the ultrasonic emission unit;

[0061] Ultrasonic sensors for:

[0062] Detect the ultrasonic waves generated by partial discharge in transformers. Four ultrasonic sensors are used to detect the arrival order of the sound wave information propagating in transformer oil and container walls.

[0063] Acoustic detection module, also includes:

[0064] Mobile sensors are used to avoid shunting and provide a clear location of the acoustic signal.

[0065] In this embodiment, the output end of the data statistics center is connected to the input end of the alarm module, the storage module and the analysis module;

[0066] The alarm module includes:

[0067] Speaker and warning light for:

[0068] Analyze the collected statistical data and determine the error value. When the error value exceeds the specified value, turn on the speaker and alarm light to sound the alarm.

[0069] Also included is a wireless transmission module for:

[0070] Send the collected statistical data and error values ​​to the remote terminal.

[0071] In this embodiment, the storage module is used to:

[0072] The STC89C58 microcontroller controls the SD card to store large amounts of data and collect statistical current data.

[0073] Analysis modules for:

[0074] By introducing artificial intelligence and machine learning technologies, it provides intelligent data analysis and decision support, and the analysis module includes automated data preprocessing, intelligent data analysis and modeling, and intelligent recommendation and prediction functions.

[0075] In this embodiment, the data statistics center includes:

[0076] Data processing module for:

[0077] The collected load data of the discharge monitoring device is compared and judged with historical data, and then the data that meets the current change amplitude judgment is marked through the current analysis module.

[0078] Specifically, the partial discharge phenomenon of the transformer will generate ultrasonic waves, which are then propagated on the transformer oil and the container wall. To detect the ultrasonic waves generated by the partial discharge phenomenon of the transformer, four ultrasonic sensors are used to detect the arrival order of the sound wave information propagating on the transformer oil and the container wall. The positioning calculation is based on the combined path calculation of the ultrasonic signal. According to the summary of the phenomena accompanying the partial discharge process of the power transformer and the actual application situation, specific methods are used for detection. In actual use, when a fault occurs, the partial discharge position can be quickly identified, which improves the local positioning effect and is conducive to long-term use. The component detection module, polarity detection module and environmental detection module are cooperated to fully detect the data information and improve the detection accuracy.

[0079] In order to solve the problem that the existing positioning system cannot ensure the detection effect of the branch circuit position in actual use, which affects the quality of detection work, please refer to Figure 3 , this embodiment provides the following technical solutions:

[0080] In this embodiment, the polarity detection module includes a tested current transformer and a standard current transformer, and the output ends of the tested current transformer and the standard current transformer are both connected to the input end of the data comparison module;

[0081] The data comparison module is used to calculate the difference between the secondary current converted to the primary current according to the current ratio and the actual secondary current. The wiring for checking the difference is the same as the wiring for checking the transformation ratio.

[0082] When the transformation ratio of the standard current transformer is the same as that of the tested current transformer, the current ratio error is the same as the current ratio difference. The ratio difference is used for detection. The wiring for checking the ratio difference is the same as the wiring for checking the transformation ratio. The ratio difference and phase difference must be measured for the current transformer after the winding is replaced. In order to ensure the correctness of the power elements, impedance elements, and differential protection, the component detection module, acoustic detection module, and environmental detection module are used to fully detect the data information to improve the detection accuracy.

[0083] Specifically, the polarity detection module tests the polarity of the current transformer after completing various insulation tests, and uses the ratio difference for detection. The wiring for checking the ratio difference is the same as the wiring for checking the transformation ratio. The ratio difference and phase difference must be measured for the current transformer after replacing the winding. In order to ensure the correctness of the power elements and impedance elements, as well as the differential protection, the component detection module, acoustic detection module and environmental detection module are cooperated to fully detect the data information to improve the detection accuracy.

[0084] In order to solve the problem that the existing positioning system cannot ensure the detection effect of the branch circuit position in actual use, which affects the quality of detection work, please refer to Figure 4 , this embodiment provides the following technical solutions:

[0085] In this embodiment, the component detection module includes a low-pass filter, an isolation follower unit and a conditioning amplifier unit, and the output ends of the low-pass filter, the isolation follower unit and the conditioning amplifier unit are all connected to the input end of the voltage extraction module;

[0086] The voltage extraction module is used to extract the voltage of the detection circuit.

[0087] In this embodiment, the component detection module is composed of a hardware circuit of low-pass filtering, isolation following, and conditioning amplification. The DC bias voltage is extracted, and the obtained DC component is adjusted by the PLC module to obtain a DC feedback amount, and after being superimposed on the fundamental wave, the DC component is adjusted by a dual closed-loop system of voltage and current for suppressing the DC bias voltage. The suppression effect of the DC bias voltage is significantly better than that of commonly used detection circuits and suppression measures, and an ideal suppression effect can be obtained under strong electromagnetic interference.

[0088] Specifically, the DC bias voltage is extracted, and the DC component obtained is adjusted by the control system to obtain the DC feedback amount, which is superimposed on the fundamental wave, and then the DC component is adjusted by the voltage and current dual closed-loop system. The detection circuit is verified by a 10KVA inverter experimental platform. It is composed of a hardware circuit of low-pass filtering, isolation following, and conditioning and amplification. The DC bias voltage is extracted, and the DC component obtained is adjusted by the PLC module to obtain the DC feedback amount, which is superimposed on the fundamental wave, and then the DC component is adjusted by the voltage and current dual closed-loop system for DC bias voltage suppression. The suppression effect of the DC bias voltage is significantly better than that of the commonly used detection circuits and suppression measures, and can achieve ideal suppression effects under strong electromagnetic interference.

[0089] Working principle: The local discharge phenomenon of the transformer will generate ultrasonic waves, which will then propagate on the transformer oil and the container wall. To detect the ultrasonic waves generated by the local discharge phenomenon of the transformer, four ultrasonic sensors are used to detect the arrival order of the sound wave information propagating on the transformer oil and the container wall. The positioning calculation is based on the combined path calculation of the ultrasonic signal. According to the summary of the phenomena accompanying the local discharge process of the power transformer, combined with the actual application situation, a specific method is used for detection. After the completion of various insulation tests, the polarity of the current transformer is tested, and the ratio difference is used for detection. The wiring of the ratio difference is the same as the wiring of the transformation ratio. The ratio difference and phase difference must be measured for the current transformer after the winding is replaced. In order to ensure the correctness of the power components and impedance components, as well as the differential protection, the current transformer is then tested. The DC bias voltage is taken, and the DC component obtained is adjusted by the control system to obtain the DC feedback amount, which is superimposed on the fundamental wave, and then the DC component is adjusted by the voltage and current dual closed-loop system. The detection circuit is verified by a 10KVA inverter experimental platform. It is composed of a hardware circuit of low-pass filtering, isolation following, and conditioning and amplification. The DC bias voltage is extracted, and the DC component obtained is adjusted by the PLC module to obtain the DC feedback amount, which is superimposed on the fundamental wave, and then the DC component is adjusted by the voltage and current dual closed-loop system for DC bias voltage suppression. The suppression effect of the DC bias voltage is significantly better than that of the commonly used detection circuits and suppression measures, and it can obtain an ideal suppression effect under strong electromagnetic interference, thereby improving the detection accuracy. In actual use, when a fault occurs, the local discharge location can be quickly found, thereby improving the local positioning effect, which is conducive to long-term use.

[0090] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0091] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that many changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the invention.

Claims

1. A system for spatially locating a transformer partial discharge source, including a data statistics center, characterized in that: The input end of the data statistics center is connected to the output ends of the acoustic detection module, the environment detection module, the polarity detection module and the component detection module; The acoustic detection module is used for: Detect the sound produced by currents of the same magnitude; The polarity detection module is used for: After each insulation test is completed, test the polarity of the current transformer, using the ratio difference for detection. Check that the wiring of the ratio difference is the same as that of the transformation ratio. The component detection module is used for: The DC bias voltage is extracted, and the obtained DC component is adjusted by the control system to obtain the DC feedback quantity. After being superimposed on the fundamental wave, the DC component is adjusted by the dual closed-loop system of voltage and current and verified by a 10kVA inverter experimental platform.

2. The system for spatially locating a transformer partial discharge source according to claim 1 is characterized in that: The data statistics center includes: Data processing module for: The collected load data of the discharge monitoring device is compared and judged with historical data, and then the data that meets the current change amplitude judgment is marked through the current analysis module.

3. The system for spatially locating a transformer partial discharge source according to claim 1 is characterized in that: The output end of the data statistics center is connected to the input ends of the alarm module, the storage module and the analysis module; The alarm module comprises: Speaker and warning light for: Analyze the collected statistical data and determine the error value. When the error value exceeds the specified value, turn on the speaker and alarm light to sound the alarm. Also included is a wireless transmission module for: Send the collected statistical data and error values ​​to the remote terminal.

4. The system for spatially locating a transformer partial discharge source according to claim 3 is characterized in that: The storage module is used for: The STC89C58 microcontroller controls the SD card to store large amounts of data and collect statistical current data. The analysis module is used to: By introducing artificial intelligence and machine learning technologies, intelligent data analysis and decision support are provided, and the analysis module includes automated data preprocessing, intelligent data analysis and modeling, and intelligent recommendation and prediction functions.

5. The system for spatially locating a transformer partial discharge source according to claim 1, characterized in that: The input end of the acoustic detection module is connected to the output end of the bass wave signal sensing unit, the noise detection unit and the sound wave movement detection unit, and the input end of the bass wave signal sensing unit, the noise detection unit and the sound wave movement detection unit is connected to the output end of the ultrasonic transmitting unit.

6. The system for spatially locating a transformer partial discharge source according to claim 1 is characterized in that: The polarity detection module includes a tested current transformer and a standard current transformer, and the output ends of the tested current transformer and the standard current transformer are both connected to the input end of the data comparison module; The data comparison module refers to the calculation of the difference between the secondary current converted to the primary current according to the current ratio and the actual secondary current, and the wiring for checking the difference is the same as the wiring for checking the transformation ratio; When the transformation ratio of the standard current transformer is the same as the transformation ratio of the current transformer under test, the current ratio error is the same as the current ratio difference.

7. The system for spatially locating a transformer partial discharge source according to claim 1 is characterized in that: The component detection module includes a low-pass filter, an isolation follower unit and a conditioning amplifier unit, and the output ends of the low-pass filter, the isolation follower unit and the conditioning amplifier unit are all connected to the input end of the voltage extraction module; The voltage extraction module is used to extract the voltage of the detection circuit.

8. The system for spatially locating a transformer partial discharge source according to claim 7 is characterized in that: The component detection module is composed of a hardware circuit of low-pass filtering, isolation following, and conditioning and amplification. The DC bias voltage is extracted. The obtained DC component is adjusted by the PLC module to obtain a DC feedback amount, and after being superimposed on the fundamental wave, the DC component is adjusted by a dual closed-loop system of voltage and current to suppress the DC bias voltage.

9. The system for spatially locating a transformer partial discharge source according to claim 1, characterized in that: The environment detection module is used for: Multi-module environmental sensors are used to detect the environment around the transformer.

10. The system for spatially locating a transformer partial discharge source according to claim 5, characterized in that: The acoustic detection module further includes: Mobile sensors are used to avoid shunting and provide localization of acoustic signals.

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