A device and method for detecting the voltage phase of a surge arrester

Abstract

This invention discloses an apparatus and method for detecting the voltage phase of a surge arrester, relating to the field of electrical measurement technology. The apparatus includes a measurement module, and the method includes obtaining the voltage phase angle α of the transformer, i.e., the phase angle between the secondary voltage and the primary voltage of the transformer; obtaining the error phase angle β of the transformer, i.e., the phase angle between the secondary voltage and the primary voltage of the transformer caused by manufacturing errors; obtaining the compensation phase angle γ of the transformer, which includes the voltage phase angle α and the error phase angle β; obtaining the surge arrester phase angle δ, i.e., the phase angle between the primary voltage and the leakage current of the surge arrester obtained by measuring using the maintenance power supply method; and obtaining the surge arrester voltage phase, which is equal to the surge arrester phase angle δ plus the compensation phase angle γ. Through the measurement module, the measured surge arrester voltage phase is more accurate.

Description

Technical Field

[0001] This invention relates to the field of electrical measurement technology, and in particular to a device and method for detecting the voltage phase of a surge arrester. Background Technology

[0002] Leakage current testing of surge arresters can effectively detect defects such as whether the inside of the surge arrester is damp or whether the metal oxide varistors have deteriorated. The angle between the primary voltage and leakage current of the surge arrester is an important parameter that is both accurate and reliable in detecting whether the inside of the surge arrester is damp or whether the varistors have aged.

[0003] 1. Wiring method of the equipment

[0004] like Figure 7 As shown, taking a 500kV substation as an example, the voltage of a conventional 500kV substation maintenance power supply box is obtained through two sets of transformers, transformer 1 and transformer 2. Transformer 1 has a YN d 11 connection group, transforming the 500kV voltage into 220kV and 35kV. The primary side has two voltage levels, 500kV and 220kV, while the secondary side has a 35kV voltage level. The 220kV voltage is distributed to the 220kV substation via the busbar and lines; the 35kV voltage is connected to transformer 2, which has a D yn 11 connection group, transforming the 35kV voltage into 380V to supply electricity for domestic use, equipment use, and the maintenance power supply box within the substation.

[0005] like Figure 1 The diagram shows the structure of the primary side of the transformer with a star connection. In a star connection, the ends of the three-phase windings are connected together to form a neutral point, and the terminals of the three-phase windings are led out separately.

[0006] like Figure 2 The diagram shown is a structural diagram of a transformer with a star connection on the secondary side.

[0007] like Figure 3 The diagram shown is a structural diagram of a transformer with a delta connection on the primary side. A delta connection is a connection where the three-phase windings are connected end to end, and the terminals of the three-phase windings are brought out separately.

[0008] like Figure 4 The diagram shown is a structural diagram of a transformer with a delta connection on the secondary side.

[0009] like Figure 5 and Figure 6As shown, the uppercase letters in the connection group indicate the primary side connection method, and the lowercase letters indicate the secondary side connection method. In the transformer connection group, YN indicates a star connection with a neutral line on the primary side; Y indicates a star connection, N indicates a connection with a neutral line; Y indicates a star connection on the primary side (without a neutral line); D indicates a delta connection on the primary side; yn indicates a star connection with a neutral line on the secondary side; y indicates a star connection on the secondary side, n indicates a connection with a neutral line; y indicates a star connection on the secondary side (without a neutral line); d indicates a delta connection on the secondary side. The numbers following the numbers indicate the position of the secondary side line voltage (vector) phasor at the clock position when the primary side line voltage (vector) phasor is at 12 o'clock.

[0010] For example, a common connection group for a 500kV transformer is YN d 11, which means that the primary side of the transformer is connected in a star configuration with a neutral line, and the secondary side is connected in a delta configuration. When the primary voltage (vector) is at 12 o'clock, the secondary voltage (vector) is at 11 o'clock. The secondary voltage lags behind the primary voltage by 30°*11=330°, or the secondary voltage leads the primary voltage by 360°-30°*11=30°.

[0011] like Figure 7 The diagram shows the distribution of the power system's transformer phase 1A, transformer phase 2A, surge arrester phase 1A, surge arrester phase 2A, surge arrester phase 3A, and maintenance power supply box. Surge arrester 1 is connected to the primary side (500kV side) lead of transformer 1, surge arrester 2 is connected to the primary side (220kV side) lead of transformer 1, and surge arrester 3 is connected to the secondary side (35kV side) lead of transformer 1.

[0012] T1 is the primary side high-voltage bushing of transformer 1 (line voltage 500kV), T2 is the primary side medium-voltage bushing of transformer 1 (line voltage 220kV), and T3 is the secondary side low-voltage bushing of transformer 1 (line voltage 35kV). T4, T5, and T6 are the primary side high-voltage bushings of transformer 2 (line voltage 35kV), and T7 to T10 are the secondary side low-voltage bushings of transformer 2. T7 is the low-voltage neutral point bushing, T8 is the C-phase low-voltage bushing, T9 is the B-phase low-voltage bushing, and T10 is the A-phase low-voltage bushing.

[0013] like Figure 7 As shown, the power supply box leads are connected from the top terminals of bushings T7, T8, T9, and T10.

[0014] like Figure 7 As shown, the A, B, and C phase leads of the secondary side of transformer 1 are connected to the A, B, and C phase leads of the primary side of transformer 2, respectively.

[0015] like Figure 7As shown, the primary lead of surge arrester 1 is connected to the primary side (500kV side) lead of transformer 1.

[0016] like Figure 7 As shown, the primary lead of surge arrester 2 is connected to the primary side (220kV side) lead of transformer 1.

[0017] like Figure 7 As shown, the primary lead of surge arrester 3 is connected to the secondary (35kV side) lead of transformer 1.

[0018] like Figure 7 As shown, the bottom of the surge arrester is grounded via a monitoring ammeter.

[0019] 2. Leakage current test voltage sampling method

[0020] Accurately obtaining the phase of the primary voltage (vector) of a surge arrester plays a crucial role in accurately testing the angle between the primary voltage and the leakage current of the surge arrester. Currently, there are generally four methods for voltage sampling: the secondary voltage method, the maintenance power supply method, the induction plate method, and the end-screen current method.

[0021] a) Secondary Voltage Method. The voltage signal is taken from the secondary voltage of the voltage transformer in the same bay as the metal oxide arrester under test. The test phase is fed back to the resistive current tester via wired or wireless transmission. This test method is accurate and suitable for obtaining the secondary voltage signal of the voltage transformer on the same busbar as the metal oxide arrester under test.

[0022] b) Maintenance power supply method. By measuring the 220V AC maintenance power supply as a virtual reference voltage, the reference signal wiring is simple and safe. However, the accuracy of testing the angle between the primary voltage and leakage current of the surge arrester is poor.

[0023] c) Induction Plate Method. This method involves placing an induction plate on the base of the metal oxide arrester, creating a capacitance between the induction plate and the high-voltage conductor. The instrument uses the capacitive current as a reference to decompose the total current of the metal oxide arrester. Because the induction plate is highly sensitive to its position, this testing method is significantly affected by external electric fields. For example, when testing arresters on the main transformer side or when there are horizontal busbars above the instrument, the measurement results may have a large error.

[0024] d) End-screen current method. Select the end-screen current of a capacitive device of the same voltage level as a reference. The capacitive device can be a current transformer or a voltage transformer. This method is limited by the field equipment; sampling will not be possible if the field capacitive device does not have its end screen led out.

[0025] 3. Power supply inspection method

[0026] like Figure 8As shown, the two current measuring lines of the surge arrester leakage current tester are connected to the two ends of the monitoring ammeter A at the bottom of the surge arrester. By short-circuiting the monitoring ammeter A, the leakage current is simultaneously introduced into the surge arrester leakage current tester to measure the leakage current. The four voltage measuring lines of the surge arrester leakage current tester are connected to terminals a, b, c, and o of the maintenance power supply box to measure the phase of the primary voltage of the surge arrester. The instrument's internal analysis and calculations measure the leakage current, resistive current, and the angle between the leakage current (vector) and the primary voltage (vector) of the surge arrester.

[0027] The search query TACD_ALL:(surge arrester AND compensation angle) yielded the following relatively relevant technical documents:

[0028] The application, published under CN 105548765 A, is titled "GIS Zinc Oxide Surge Arrester Live-Line Tester." It achieves live-line testing of GIS surge arresters by acquiring voltage signals from a maintenance power supply or a substation 220V power supply, while minimizing testing errors. To achieve this objective, the GIS zinc oxide surge arrester live-line tester includes a main unit, a voltage isolator, and a data transmission system. The main unit includes a reference signal input terminal, a current input terminal, a wireless signal receiver, and a grounding terminal. The voltage isolator includes a reference voltage input terminal and a voltage signal output terminal. The main unit also houses a phase detector, which is connected to a phase calibrator and the maintenance power supply or substation 220V power supply to acquire voltage signals. This configuration allows the GIS zinc oxide surge arrester live-line tester to simultaneously measure three-phase MOA (Mean Activity Amount) or perform single-phase measurements, and it automatically compensates for phase-to-phase interference.

[0029] The authorization announcement number is CN 111579905 B, entitled "A Method for Live Testing of Series-Compensated Zinc Oxide Surge Arresters." This method involves collecting leakage current and secondary voltage signals from both ends of the series-compensated zinc oxide surge arrester during live testing. Specifically, it collects the current I3 in the branch containing the series compensation capacitor, the current I1 in the zinc oxide surge arrester MOA1, the voltage U1 in the capacitive voltage transformer CVT1, the current I2 in the zinc oxide surge arrester MOA1, and the voltage U2 in the capacitive voltage transformer CVT2. The method calculates the voltage angle difference between the two ends of the series-compensated zinc oxide surge arrester and adds an interphase interference compensation angle to correct the collected data. This addresses the measurement error problem caused by the series compensation during live testing, ensuring the safe operation of the power grid.

[0030] The application, published under CN 104635088 A, is titled "Intelligent Induction Device for Zinc Oxide Surge Arrester Tester." It includes a main unit, a miniature printer, a charging socket, a measuring grounding terminal, a power switch, a touch keyboard, a large-screen LCD display, and input terminals. The input terminals include a reference voltage input terminal and a current input terminal. The current input includes leakage current input terminals for phase A, phase B, and phase C. The miniature printer, charging socket, measuring grounding terminal, power switch, touch keyboard, large-screen LCD display, and input terminals are all mounted on the main unit. This technical solution is simple to operate and easy to use. It can measure the total current, resistive current, harmonics, power frequency reference voltage, active power, and phase difference of zinc oxide surge arresters. The large-screen LCD display can show the actual waveforms of voltage and current. Furthermore, this technical solution utilizes digital waveform analysis technology and employs anti-interference methods such as harmonic analysis and digital filtering to ensure accurate and stable measurement results.

[0031] The application, published under CN 114167169 A, is titled "A Signal Acquisition Device for Live-Line Testing of Surge Arresters." It includes a housing, a current input module, a reference signal receiving module, a charging module, a safety module, and a display module. The housing is fixedly connected to these modules. The current input module has three channels and includes a processing unit for calculating phase-to-phase interference and automatically compensating for the data. The reference signal receiving module includes a wired module, a wireless module, and a voltage isolator on the induction plate. The wired module connects to the voltage isolator, the wireless module has an antenna, and the induction plate connects to the circuit under test. The charging module integrates a communication module. Compared to traditional solutions, this solution allows for simultaneous measurement of three-phase MOA without contacting the PT terminal box, automatically compensates for phase-to-phase interference, and can use a maintenance power supply or a 220V power supply as a reference. The data is stable and reliable, and the system is safe and secure.

[0032] The authorization notice number is CN 103353542 B, and the name is "Surge Arrester Three-Phase Simultaneous Testing Lead Clamp". A grooved track is provided on the slide. The upper jaw is coaxially fixed to the upper end of the slide with a fixed pulley, and the lower jaw is coaxial with a movable pulley. The movable pulley moves the lower jaw up and down along the track. A control rod is connected to the lower end of the slide. The control rod consists of two rods nested together. The inner cavity of the inner control rod is connected to the grooved track of the slide. A connecting block is provided in the inner cavity of the inner control rod. A connecting rod is connected to the lower end of the connecting block, and the connecting rod is connected to the outer control rod. The upper end of the connecting block is connected to a steel wire rope, which passes around the fixed pulley and connects to the movable pulley. This clamp can perform three-phase simultaneous measurements, completely eliminating the need for testing personnel to frequently use insulated ladders to climb and retrieve test leads. Testing can be completed on the ground using the device, greatly improving the efficiency and safety of surge arrester live-line testing.

[0033] The application, published under CN 102565558 A, is titled "Live Testing Method for Zinc Oxide Surge Arresters." This method employs a three-phase simultaneous testing approach, wireless sampling, and phase-to-phase interference compensation. Utilizing capacitive plates for wireless voltage signal acquisition, this method significantly reduces the threat posed by high voltage to operators, offering simple, safe, and reliable operation. It effectively addresses the influence of human error and other factors on measurements, ensuring data accuracy and significantly improving work efficiency. Furthermore, it provides reasonable compensation for test errors, allowing for a more accurate assessment of the zinc oxide surge arrester's performance based on the test results.

[0034] Based on the above six patent documents and existing technical solutions, the inventors have identified the following technical problems in the existing technical solutions.

[0035] Each of the four voltage sampling test methods has its shortcomings. The secondary voltage method has poor safety and is prone to malfunctions of the protection system due to improper operation. The maintenance power supply method has poor accuracy in the angle between the primary voltage (vector) and leakage current (vector) of the surge arrester. The induction plate method has poor accuracy. The end screen current method is limited by the field equipment and cannot be sampled when the field capacitive equipment does not lead out the end screen.

[0036] This application addresses the technical problem of the inaccuracy of the angle between the primary voltage (vector) and leakage current (vector) of the surge arrester in the maintenance power supply method, with the aim of improving the accuracy of the angle between the primary voltage (vector) and leakage current (vector) of the surge arrester in the maintenance power supply method.

[0037] Existing technical issues and considerations:

[0038] How to solve the technical problem of poor phase accuracy of surge arrester voltage obtained by measurement. Summary of the Invention

[0039] The technical problem to be solved by the present invention is to provide a device and method for detecting the voltage phase of a surge arrester, thereby solving the technical problem of poor accuracy of the measured voltage phase of the surge arrester.

[0040] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A device for detecting the voltage phase of a surge arrester includes a measurement module, which is a program module used to obtain the voltage phase angle α of the transformer, that is, the phase angle between the secondary voltage and the primary voltage of the transformer; to obtain the error phase angle β of the transformer, that is, the phase angle between the secondary voltage and the primary voltage of the transformer caused by manufacturing errors of the transformer; to obtain the compensation phase angle γ of the transformer, which includes the voltage phase angle α and the error phase angle β; to obtain the surge arrester phase angle δ, that is, the phase angle between the primary voltage and the leakage current of the surge arrester obtained by measuring using the maintenance power supply method; and to obtain the surge arrester voltage phase, which is equal to the surge arrester phase angle δ plus the compensation phase angle γ.

[0041] A further technical solution is that the voltage phase angle α is the phase angle at which the secondary voltage of the transformer lags behind or precedes the primary voltage.

[0042] A further technical solution is as follows: the voltage phase angle α includes the voltage phase angle α1 of the first transformer and the voltage phase angle α2 of the second transformer; the error phase angle β includes the error phase angle β1 of the first transformer and the error phase angle β2 of the second transformer; the compensation phase angle γ of the transformer includes the compensation phase angle γ1 of the first transformer and the compensation phase angle γ2 of the second transformer; the compensation phase angle γ1 of the first transformer is the sum of the voltage phase angle α1 of the first transformer and the error phase angle β1 of the first transformer; and the compensation phase angle γ2 of the second transformer is the sum of the voltage phase angle α2 of the second transformer and the error phase angle β2 of the second transformer.

[0043] A further technical solution is that: the voltage phase angle α is the voltage phase angle α2 of the second transformer, the error phase angle β is the error phase angle β2 of the second transformer, the compensation phase angle γ of the transformer is the compensation phase angle γ2 of the second transformer, and the compensation phase angle γ2 of the second transformer is the sum of the voltage phase angle α2 of the second transformer and the error phase angle β2 of the second transformer.

[0044] A further technical solution includes: a surge arrester leakage current tester for obtaining the surge arrester phase angle δ and an angle difference ratio tester for obtaining the transformer error phase angle β. The surge arrester leakage current tester is connected and communicates with the angle difference ratio tester. The measurement module runs on the controller of the surge arrester leakage current tester. The measurement module is also used by the surge arrester leakage current tester to obtain the transformer voltage phase angle α, and the angle difference ratio tester to obtain the transformer error phase angle β and send it to the surge arrester leakage current tester. The surge arrester leakage current tester obtains the transformer compensation phase angle γ, obtains the surge arrester phase angle δ, and obtains the surge arrester voltage phase.

[0045] A method for detecting the voltage phase of a surge arrester includes the following steps: obtaining the voltage phase angle α of the transformer, i.e., the phase angle between the secondary voltage and the primary voltage of the transformer; obtaining the error phase angle β of the transformer, i.e., the phase angle between the secondary voltage and the primary voltage of the transformer caused by manufacturing errors; obtaining the compensation phase angle γ of the transformer, the compensation phase angle γ including the voltage phase angle α and the error phase angle β; obtaining the surge arrester phase angle δ, i.e., the phase angle between the primary voltage and the leakage current of the surge arrester obtained by measuring using the maintenance power supply method; and obtaining the surge arrester voltage phase, which is equal to the surge arrester phase angle δ plus the compensation phase angle γ.

[0046] A further technical solution is as follows: Based on a surge arrester leakage current tester for obtaining the surge arrester phase angle δ and an angle difference ratio tester for obtaining the transformer error phase angle β, the surge arrester leakage current tester and the angle difference ratio tester are connected and communicate. In the measurement step, the surge arrester leakage current tester obtains the transformer voltage phase angle α, the angle difference ratio tester obtains the transformer error phase angle β and sends it to the surge arrester leakage current tester, the surge arrester leakage current tester obtains the transformer compensation phase angle γ, obtains the surge arrester phase angle δ, and obtains the surge arrester voltage phase.

[0047] A further technical solution is that, in the measurement step, the surge arrester leakage current tester obtains the voltage phase angle α of the transformer and records it into the surge arrester leakage current tester.

[0048] An apparatus for detecting the voltage phase of a surge arrester includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the corresponding steps in the method described above.

[0049] An apparatus for detecting the voltage phase of a surge arrester includes a computer-readable storage medium storing a computer program that, when executed by a processor, implements the corresponding steps in the method described above.

[0050] The beneficial effects of adopting the above technical solution are as follows:

[0051] A device for detecting the voltage phase of a surge arrester includes a measurement module, which is a program module used to obtain the voltage phase angle α of the transformer (i.e., the phase angle between the secondary and primary voltages), the error phase angle β (i.e., the phase angle between the secondary and primary voltages caused by manufacturing errors), the compensation phase angle γ (which includes both the voltage phase angle α and the error phase angle β), and the surge arrester phase angle δ (i.e., the phase angle between the primary voltage and leakage current of the surge arrester measured using the maintenance power supply method). The surge arrester voltage phase is equal to the surge arrester phase angle δ plus the compensation phase angle γ. This technical solution, through the measurement module, achieves more accurate measurement of the surge arrester voltage phase.

[0052] A method for detecting the voltage phase of a surge arrester includes the following steps: obtaining the voltage phase angle α of the transformer (the phase angle between the secondary and primary voltages); obtaining the error phase angle β of the transformer (the phase angle between the secondary and primary voltages caused by manufacturing errors); obtaining the compensation phase angle γ of the transformer, which includes both the voltage phase angle α and the error phase angle β; obtaining the surge arrester phase angle δ, which is the phase angle between the primary voltage and leakage current of the surge arrester measured using the maintenance power supply method; and obtaining the surge arrester voltage phase, which is equal to the surge arrester phase angle δ plus the compensation phase angle γ. This technical solution, through measurement steps, achieves a more accurate measured surge arrester voltage phase.

[0053] An apparatus for detecting the voltage phase of a surge arrester includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the corresponding steps in the method described above. This technical solution achieves more accurate measurement of the surge arrester voltage phase.

[0054] An apparatus for detecting the voltage phase of a surge arrester includes a computer-readable storage medium storing a computer program that, when executed by a processor, performs the corresponding steps in the method described above. This technical solution achieves more accurate measurement of the surge arrester voltage phase.

[0055] See the detailed implementation section for further description. Attached Figure Description

[0056] Figure 1 This is a structural diagram of a transformer with a star connection on the primary side;

[0057] Figure 2 This is a structural diagram of a transformer with a star connection on the secondary side;

[0058] Figure 3 This is a structural diagram of a transformer with a delta connection on the primary side;

[0059] Figure 4 This is a structural diagram of a transformer with a delta connection on the secondary side;

[0060] Figure 5 This is a vector diagram of the phase voltages of YN d 11.

[0061] Figure 6 This is the wiring diagram for YN d 11;

[0062] Figure 7 This is a distribution map of 500kV substations;

[0063] Figure 8 This is the wiring diagram for the leakage current of the surge arrester under the power supply method for maintenance;

[0064] Figure 9 This is a flowchart of Embodiment 4 of the present invention;

[0065] Figure 10 This is a flowchart of Embodiment 5 of the present invention. Detailed Implementation

[0066] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this application or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0067] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0068] Example 1:

[0069] This invention discloses a device for detecting the voltage phase of a surge arrester, comprising a measurement module, which is a program module, used to obtain the voltage phase angle α of the transformer, i.e., the phase angle between the secondary voltage and the primary voltage of the transformer; to obtain the error phase angle β of the transformer, i.e., the phase angle between the secondary voltage and the primary voltage of the transformer caused by manufacturing errors; to obtain the compensation phase angle γ of the transformer, which includes the voltage phase angle α and the error phase angle β; to obtain the surge arrester phase angle δ, i.e., the phase angle between the primary voltage and the leakage current of the surge arrester obtained by measuring using the maintenance power supply method; and to obtain the surge arrester voltage phase, which is equal to the surge arrester phase angle δ plus the compensation phase angle γ.

[0070] The voltage phase angle α includes the voltage phase angle α1 of the first transformer and the voltage phase angle α2 of the second transformer. The error phase angle β includes the error phase angle β1 of the first transformer and the error phase angle β2 of the second transformer. The compensation phase angle γ of the transformer includes the compensation phase angle γ1 of the first transformer and the compensation phase angle γ2 of the second transformer. The compensation phase angle γ1 of the first transformer is the sum of the voltage phase angle α1 of the first transformer and the error phase angle β1 of the first transformer. The compensation phase angle γ2 of the second transformer is the sum of the voltage phase angle α2 of the second transformer and the error phase angle β2 of the second transformer.

[0071] like Figure 7 As shown, Example 1 is used to measure the first surge arrester and the second surge arrester. The first surge arrester is surge arrester 1, the second surge arrester is surge arrester 2, the first transformer is transformer 1, and the second transformer is transformer 2.

[0072] Example 2:

[0073] This invention discloses a device for detecting the voltage phase of a surge arrester, comprising a measurement module, which is a program module, used to obtain the voltage phase angle α of the transformer, i.e., the phase angle between the secondary voltage and the primary voltage of the transformer; to obtain the error phase angle β of the transformer, i.e., the phase angle between the secondary voltage and the primary voltage of the transformer caused by manufacturing errors; to obtain the compensation phase angle γ of the transformer, which includes the voltage phase angle α and the error phase angle β; to obtain the surge arrester phase angle δ, i.e., the phase angle between the primary voltage and the leakage current of the surge arrester obtained by measuring using the maintenance power supply method; and to obtain the surge arrester voltage phase, which is equal to the surge arrester phase angle δ plus the compensation phase angle γ.

[0074] The voltage phase angle α is the voltage phase angle α2 of the second transformer, the error phase angle β is the error phase angle β2 of the second transformer, the compensation phase angle γ of the transformer is the compensation phase angle γ2 of the second transformer, and the compensation phase angle γ2 of the second transformer is the sum of the voltage phase angle α2 of the second transformer and the error phase angle β2 of the second transformer.

[0075] like Figure 7 As shown, Example 2 is used to measure the third surge arrester, which is surge arrester 3.

[0076] Example 3:

[0077] This invention discloses a device for detecting the voltage phase of a surge arrester, comprising a surge arrester leakage current tester for obtaining the phase angle δ of the surge arrester, an angle difference ratio tester for obtaining the transformer error phase angle β, and a measurement module running on the controller of the surge arrester leakage current tester. The surge arrester leakage current tester and the angle difference ratio tester are wired and communicate with each other.

[0078] The measurement module is a program module used by the surge arrester leakage current tester to obtain the voltage phase angle α of the transformer, the angle difference ratio tester to obtain the error phase angle β of the transformer and send it to the surge arrester leakage current tester, and the surge arrester leakage current tester to obtain the compensation phase angle γ of the transformer, obtain the surge arrester phase angle δ, and obtain the surge arrester voltage phase.

[0079] The improvement in this embodiment lies in the measurement module, which combines the measurement modules of Embodiment 1 and Embodiment 2, and can be selected for use according to measurement needs.

[0080] The voltage phase angle α of the transformer is obtained by the surge arrester leakage current tester by the measurement personnel through reading the nameplate on the transformer and manually entering the voltage phase angle α into the surge arrester leakage current tester through its own input unit.

[0081] Among them, the angle difference and ratio difference tester is a single-chip microcomputer controller. The surge arrester leakage current tester and the angle difference and ratio difference tester themselves, as well as the corresponding communication connection technology, are existing technologies and will not be described in detail here.

[0082] Compared to the above embodiments, electronic tags can also be installed on the transformer. The voltage phase angle α of the transformer is pre-recorded in its electronic tag. An electronic tag reader is installed in the surge arrester leakage current tester. The controller in the surge arrester leakage current tester is wired to and communicates with the electronic tag reader. The electronic tag reader obtains the voltage phase angle α of the transformer under test through wireless identification.

[0083] Compared to the above embodiments, a QR code label containing the transformer voltage phase angle α can also be installed on the transformer. A scanner is installed in the surge arrester leakage current tester. The controller in the surge arrester leakage current tester is wired to and communicates with the scanner. The scanner obtains the voltage phase angle α of the transformer under test by scanning and recognizing the QR code label.

[0084] Compared to the above embodiment, the voltage phase angle α is the phase angle by which the secondary voltage of the transformer lags behind the primary voltage.

[0085] Compared to the above embodiment, the voltage phase angle α is the phase angle at which the secondary voltage of the transformer precedes the primary voltage.

[0086] Example 4:

[0087] like Figure 9 As shown, this invention discloses a method for detecting the voltage phase of a surge arrester. Based on a surge arrester leakage current tester for obtaining the surge arrester phase angle δ and an angle difference ratio tester for obtaining the transformer error phase angle β, as well as the measurement module of Example 1, the surge arrester leakage current tester and the angle difference ratio tester are wirelessly connected and communicate with each other. The measurement steps are as follows:

[0088] The measurement personnel read the nameplate on the transformer to obtain the voltage phase angle α of the transformer and input it into the surge arrester leakage current tester through its own input unit. The surge arrester leakage current tester obtains the voltage phase angle α of the transformer, that is, the phase angle between the secondary voltage and the primary voltage of the transformer. The phase angle difference tester obtains the error phase angle β of the transformer and sends it to the surge arrester leakage current tester. The error phase angle β of the transformer is the phase angle between the secondary voltage and the primary voltage of the transformer caused by the transformer manufacturing error. The surge arrester leakage current tester obtains the compensation phase angle γ of the transformer. The compensation phase angle γ includes the voltage phase angle α and the error phase angle β. The surge arrester leakage current tester obtains the surge arrester phase angle δ, that is, the phase angle between the primary voltage and the leakage current of the surge arrester obtained by measuring using the maintenance power supply method. The surge arrester leakage current tester obtains the surge arrester voltage phase, which is equal to the surge arrester phase angle δ plus the compensation phase angle γ.

[0089] The voltage phase angle α includes the voltage phase angle α1 of the first transformer and the voltage phase angle α2 of the second transformer. The error phase angle β includes the error phase angle β1 of the first transformer and the error phase angle β2 of the second transformer. The compensation phase angle γ of the transformer includes the compensation phase angle γ1 of the first transformer and the compensation phase angle γ2 of the second transformer. The compensation phase angle γ1 of the first transformer is the sum of the voltage phase angle α1 of the first transformer and the error phase angle β1 of the first transformer. The compensation phase angle γ2 of the second transformer is the sum of the voltage phase angle α2 of the second transformer and the error phase angle β2 of the second transformer.

[0090] The surge arrester leakage current tester's own input unit is a touch screen.

[0091] The angle difference ratio and leakage current are not measured simultaneously. The angle difference ratio is the measured value before the transformer is energized after installation, while the leakage current is the measured value after the transformer is energized and under voltage.

[0092] like Figure 9 As shown, the first transformer is transformer 1, the second transformer is transformer 2, the voltage phase angle α1 of the first transformer is the wiring group deviation α1, the voltage phase angle α2 of the second transformer is the wiring group deviation α2, the error phase angle β1 of the first transformer is the equipment deviation β1, the error phase angle β2 of the second transformer is the equipment deviation β2, the compensation phase angle γ1 of the first transformer is the angle γ1 that transformer 1 needs to compensate, the compensation phase angle γ2 of the second transformer is the angle γ2 that transformer 2 needs to compensate, the compensation phase angle γ of the transformer is the total angle γ3 that needs to be compensated, and the surge arrester phase angle δ is the surge arrester phase angle δ.

[0093] Example 5:

[0094] like Figure 10 As shown, this invention discloses a method for detecting the voltage phase of a surge arrester. Based on a surge arrester leakage current tester for obtaining the surge arrester phase angle δ and an angle difference ratio tester for obtaining the transformer error phase angle β, as well as the measurement module of Example 2, the surge arrester leakage current tester and the angle difference ratio tester are wirelessly connected and communicate with each other. The measurement steps are as follows:

[0095] The measurement personnel read the nameplate on the transformer to obtain the voltage phase angle α of the transformer and input it into the surge arrester leakage current tester through its own input unit. The surge arrester leakage current tester obtains the voltage phase angle α of the transformer, that is, the phase angle between the secondary voltage and the primary voltage of the transformer. The phase angle difference tester obtains the error phase angle β of the transformer and sends it to the surge arrester leakage current tester. The error phase angle β of the transformer is the phase angle between the secondary voltage and the primary voltage of the transformer caused by the transformer manufacturing error. The surge arrester leakage current tester obtains the compensation phase angle γ of the transformer. The compensation phase angle γ includes the voltage phase angle α and the error phase angle β. The surge arrester leakage current tester obtains the surge arrester phase angle δ, that is, the phase angle between the primary voltage and the leakage current of the surge arrester obtained by measuring using the maintenance power supply method. The surge arrester leakage current tester obtains the surge arrester voltage phase, which is equal to the surge arrester phase angle δ plus the compensation phase angle γ.

[0096] The voltage phase angle α is the voltage phase angle α2 of the second transformer, the error phase angle β is the error phase angle β2 of the second transformer, the compensation phase angle γ of the transformer is the compensation phase angle γ2 of the second transformer, and the compensation phase angle γ2 of the second transformer is the sum of the voltage phase angle α2 of the second transformer and the error phase angle β2 of the second transformer.

[0097] like Figure 10 As shown, the second transformer is transformer 2, the voltage phase angle α2 of the second transformer is the wiring group deviation α2, the error phase angle β2 of the second transformer is the equipment deviation β2, the compensation phase angle γ2 of the second transformer is the angle γ2 that transformer 2 needs to compensate, and the surge arrester phase angle δ is the surge arrester phase angle δ.

[0098] Example 6:

[0099] The present invention discloses a device for detecting the voltage phase of a surge arrester, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of embodiment 4.

[0100] Example 7:

[0101] The present invention discloses a device for detecting the voltage phase of a surge arrester, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of embodiment 5.

[0102] Example 8:

[0103] The present invention discloses a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps in Embodiment 4.

[0104] Example 9:

[0105] The present invention discloses a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps in Embodiment 5.

[0106] The concept of this application:

[0107] 1. Technical problems to be solved

[0108] This application addresses the technical problem of improving the accuracy of the angle between the primary voltage (vector) and leakage current (vector) of a surge arrester in the maintenance power supply method.

[0109] The inaccuracy of the maintenance power supply method for measurement stems from two main reasons: first, different transformer connection groups cause the secondary voltage (vector) to lag behind the primary voltage (vector), resulting in an angle difference, referred to as connection group deviation; second, manufacturing errors in the transformer cause inherent angle differences between the primary and secondary voltages (vectors), referred to as equipment deviation. This application aims to reduce connection group deviation and equipment deviation, thereby improving the accuracy of the angle between the primary voltage (vector) and leakage current (vector) of a surge arrester tested using the maintenance power supply method.

[0110] 2. Technical Solution Description

[0111] When the surge arrester leakage current tester takes a voltage (vector) signal from the maintenance power supply box to measure the surge arrester leakage current, the phase of the measured voltage is the phase of the voltage (vector) in the maintenance power supply box. The test result is compensated by a certain angle so that the angle of the measured voltage (vector) is the same as the angle of the primary voltage (vector) of the surge arrester.

[0112] ① Compensation principle

[0113] Therefore, the core of the problem lies in finding the accurate angle that the voltage (vector) of the power supply box needs to be compensated for.

[0114] The calculation is performed in two steps.

[0115] 1) Calculate the wiring group deviation

[0116] Different transformer connection groups cause a lag between the secondary voltage and the primary voltage, resulting in an angle difference, referred to as connection group deviation. Taking transformer 1 with connection group YN d 11 as an example, where connection group YN d 11 is given on the equipment nameplate, the secondary voltage lags the primary voltage by 11*30°. That is, after subtracting 11*30°, the secondary voltage is in phase with the primary voltage (vector). Therefore, a compensation of α1 = -11*30° is needed to maintain the same angle between the primary and secondary voltages (vectors). Similarly, a transformer with connection group Y y 6 requires a compensation of α1 = -6*30° to maintain the same phase between the primary and secondary voltages (vectors). Compensation methods for other connection groups are calculated accordingly.

[0117] 2) Measurement equipment deviation

[0118] Because there are always errors in transformer manufacturing, the phase relationship between the secondary voltage and the primary voltage of a transformer cannot be calculated entirely according to the wiring group. In addition to the angle difference caused by the wiring group, there is also the manufacturing error of the transformer itself, which is referred to as equipment deviation. Taking transformer 1 as an example, the angle β1 by which the secondary voltage (vector) of a single-phase transformer 1 lags behind the primary voltage (vector) is measured using an "angle difference and ratio difference tester". [If the primary side of the surge arrester under test is connected to the primary side (500kV side) of transformer 1, the angle by which the secondary voltage (vector) of transformer 1 lags behind the primary voltage (vector) of the primary side (500kV side) is measured; if the primary side of the surge arrester under test is connected to the primary side (220kV side) of transformer 1, the angle by which the secondary voltage (vector) of transformer 1 lags behind the primary voltage (vector) of the primary side (220kV side) is measured.] The secondary voltage (vector) of transformer 1 lags behind the primary voltage (vector) by -β1, that is, the secondary voltage minus -β1° is in phase with the primary voltage (vector). Therefore, compensation of -(-β1) = β1 is required to keep the primary voltage (vector) and the secondary voltage (vector) in phase.

[0119] 3) Overall compensation perspective

[0120] From steps 1) and 2), it can be seen that transformer 1 needs to compensate for equipment deviations α1 and β1. After compensation γ1 = (α1 + β1), the primary voltage and secondary voltage of the transformer are in phase. The angle that needs to be compensated is...

[0121] γ1=(α1+β1).

[0122] That is, the total compensation angle = - number of connection points on the nameplate of transformer 1 × 30° + equipment deviation of transformer 1

[0123] ②Specific testing process

[0124] Test in three scenarios:

[0125] like Figure 7 As shown, the leakage current of surge arrester 1, surge arrester 2 and surge arrester 3 are analyzed respectively.

[0126] To test the leakage current of surge arrester 1, the voltage on the primary side (500kV side) of surge arrester 1 needs to be transformed twice by transformer 1 and transformer 2 to obtain the voltage of the maintenance power supply box. Therefore, it is necessary to compensate for the angle difference caused by transformer 1 and transformer 2.

[0127] like Figure 9 The specific process is shown below. To test the leakage current of surge arrester 2, the primary side (220kV side) voltage of surge arrester 2 needs to be transformed twice by transformers 1 and 2 to obtain the voltage of the maintenance power supply box. Therefore, it is necessary to compensate for the angle difference caused by transformers 1 and 2.

[0128] like Figure 10 The specific process is shown below. To test the leakage current of surge arrester 3, the primary side (35kV side) voltage of surge arrester 3 needs to be transformed by transformer 2 to obtain the voltage of the maintenance power supply box. Therefore, it is necessary to compensate for the angle difference caused by the surge arresters in transformer 2.

[0129] After this application was kept confidential for a period of time, the beneficial aspects reported by the on-site technical personnel were:

[0130] By using surge arresters of different voltage levels to compensate for different angles, the accuracy of voltage sampling in the maintenance power supply method can be improved.

[0131] 1. Conception

[0132] The wiring group is calculated to compensate for the wiring group deviation; the transformer angle difference is tested to compensate for the equipment deviation, and the total compensation angle is calculated. The compensation angle is then added to the angle between the tested primary voltage (vector) and leakage current (vector) of the surge arrester to obtain the true angle between the primary voltage (vector) and leakage current (vector) of the surge arrester.

[0133] 2. Accuracy testing of the improved maintenance power supply method

[0134] The angle between the primary voltage (vector) and leakage current (vector) of a 220kV surge arrester was tested using the conventional maintenance power supply sampling method, the improved maintenance power supply sampling method, and the secondary voltage method (the voltage sampling method with the highest accuracy).

[0135] Table 1 shows a comparison of test data from the secondary voltage method, the conventional maintenance power supply sampling method, and the improved maintenance power supply sampling method. Using the secondary voltage method as the benchmark, the improved maintenance power supply method shows a deviation within 0.5% compared to the secondary voltage method, indicating that the deviation is influenced by the accuracy of the testing instruments, and both methods are at a similar level of accuracy. The conventional maintenance power supply sampling method, compared to the secondary voltage method, shows a maximum deviation of -75.83%, a huge deviation with no reference value. Therefore, the improved maintenance power supply method has a test accuracy close to that of the secondary voltage method, which has the highest test accuracy, thus meeting the requirements for test accuracy.

[0136] Table 1: Comparison of Test Data

[0137]

[0138] Currently, the technical solution of this invention has undergone pilot testing, which is a small-scale trial of the product before large-scale mass production. After the pilot testing was completed, a user survey was conducted on a small scale, and the survey results showed that user satisfaction was high. Now, preparations have begun for the formal production and industrialization of the product (including intellectual property risk warning surveys).

Claims

1. A device for detecting the voltage phase of a surge arrester, characterized in that: It includes a measurement module, which is a program module used to obtain the voltage phase angle α of the transformer, that is, the phase angle between the secondary voltage and the primary voltage of the transformer; to obtain the error phase angle β of the transformer, that is, the phase angle between the secondary voltage and the primary voltage of the transformer caused by manufacturing errors; to obtain the compensation phase angle γ of the transformer, which includes the voltage phase angle α and the error phase angle β; to obtain the arrester phase angle δ, that is, the phase angle between the primary voltage and the leakage current of the arrester obtained by measuring using the maintenance power supply method; and to obtain the arrester voltage phase, which is equal to the arrester phase angle δ plus the compensation phase angle γ.

2. The device for detecting the voltage phase of a surge arrester according to claim 1, characterized in that: The voltage phase angle α is the phase angle at which the secondary voltage of the transformer lags behind or precedes the primary voltage.

3. The device for detecting the voltage phase of a surge arrester according to claim 1, characterized in that: The voltage phase angle α includes the voltage phase angle α1 of the first transformer and the voltage phase angle α2 of the second transformer. The error phase angle β includes the error phase angle β1 of the first transformer and the error phase angle β2 of the second transformer. The compensation phase angle γ of the transformer includes the compensation phase angle γ1 of the first transformer and the compensation phase angle γ2 of the second transformer. The compensation phase angle γ1 of the first transformer is the sum of the voltage phase angle α1 of the first transformer and the error phase angle β1 of the first transformer. The compensation phase angle γ2 of the second transformer is the sum of the voltage phase angle α2 of the second transformer and the error phase angle β2 of the second transformer.

4. The device for detecting the voltage phase of a surge arrester according to claim 1, characterized in that: The voltage phase angle α is the voltage phase angle α2 of the second transformer, the error phase angle β is the error phase angle β2 of the second transformer, the compensation phase angle γ of the transformer is the compensation phase angle γ2 of the second transformer, and the compensation phase angle γ2 of the second transformer is the sum of the voltage phase angle α2 of the second transformer and the error phase angle β2 of the second transformer.

5. The device for detecting the voltage phase of a surge arrester according to claim 1, characterized in that: It also includes a surge arrester leakage current tester for obtaining the surge arrester phase angle δ and an angle difference ratio tester for obtaining the transformer error phase angle β. The surge arrester leakage current tester is connected and communicates with the angle difference ratio tester. The measurement module runs on the controller of the surge arrester leakage current tester. The measurement module is also used by the surge arrester leakage current tester to obtain the transformer voltage phase angle α, and the angle difference ratio tester to obtain the transformer error phase angle β and send it to the surge arrester leakage current tester. The surge arrester leakage current tester obtains the transformer compensation phase angle γ, obtains the surge arrester phase angle δ, and obtains the surge arrester voltage phase.

6. A method for detecting the voltage phase of a surge arrester, characterized in that: The process includes the following steps: obtaining the transformer's voltage phase angle α, which is the phase angle between the transformer's secondary voltage and primary voltage; obtaining the transformer's error phase angle β, which is the phase angle between the transformer's secondary voltage and primary voltage caused by manufacturing errors; obtaining the transformer's compensation phase angle γ, which includes the voltage phase angle α and the error phase angle β; obtaining the surge arrester phase angle δ, which is the phase angle between the surge arrester's primary voltage and leakage current measured using the maintenance power supply method; and obtaining the surge arrester voltage phase, which is equal to the surge arrester phase angle δ plus the compensation phase angle γ.

7. A method for detecting the voltage phase of a surge arrester according to claim 6, characterized in that: Based on the surge arrester leakage current tester for obtaining the surge arrester phase angle δ and the angle difference ratio tester for obtaining the transformer error phase angle β, the surge arrester leakage current tester and the angle difference ratio tester are connected and communicate. In the measurement step, the surge arrester leakage current tester obtains the transformer voltage phase angle α, the angle difference ratio tester obtains the transformer error phase angle β and sends it to the surge arrester leakage current tester, the surge arrester leakage current tester obtains the transformer compensation phase angle γ, obtains the surge arrester phase angle δ, and obtains the surge arrester voltage phase.

8. A method for detecting the voltage phase of a surge arrester according to claim 7, characterized in that: In the measurement step, the surge arrester leakage current tester obtains the voltage phase angle α of the transformer and records it into the surge arrester leakage current tester.

9. A device for detecting the voltage phase of a surge arrester, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, it implements the corresponding steps in the method of any one of claims 6 to 8.

10. An apparatus for detecting the voltage phase of a surge arrester includes a computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by the processor, it implements the corresponding steps in the method of any one of claims 6 to 8.

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