Real-time detection method and device for open delta circuit disconnection fault of voltage transformer

Abstract

The disclosure provides a voltage transformer open delta circuit disconnection fault real-time detection method and device, and relates to the technical field of power system relay protection. The method comprises the following steps: loading a detection voltage to a generator neutral point grounding transformer under the condition that the generator does not work; detecting the electric data of the voltage transformer open delta circuit coupled to the generator terminal through the generator neutral point grounding transformer; and determining the working state of the voltage transformer open delta circuit of the generator terminal based on the electric data. According to the disclosure, the working state of the voltage transformer open delta circuit can be detected by loading the detection voltage to the neutral point grounding transformer under the condition that the generator does not work, so that the dead zone of the generator shutdown state voltage transformer open delta loop disconnection detection can be eliminated, and the practicability is high.

Description

Technical Field

[0001] This disclosure relates to the field of power system relay protection technology, and in particular to a method, device, electronic equipment and storage medium for real-time detection of open delta circuit open faults in voltage transformers. Background Technology

[0002] Current methods for detecting open-delta circuit breaks in voltage transformers. For example, Chinese invention patent ZL201610432911.0, "Voltage Transformer Open-Delta Circuit Open Detection Device and Application Method":

[0003] 1) When the system is running normally, the sum of vectors Ua, Ub and Uc, 3U0, is zero, that is, vectors UL and ULN are at the same potential. Then, the voltage between phase Ua and phase UL is measured, which is the voltage of the secondary winding of phase A. The voltage between phase Ub and phase Uc, and the voltage between phase Ub and phase UL are measured, which are the voltages of the secondary single-phase windings of the corresponding transformers.

[0004] 2) Determining the location of the open circuit: When the voltage difference between any phase and the UL phase is less than or equal to 40V due to the loss of the reference voltage Ux, it is determined that an open circuit has occurred on the UL phase side of the open delta circuit. The open circuit indicator light and the alarm indicator light will illuminate. When the voltage difference between any phase and the UL phase is less than or equal to 40V, it is determined that an open circuit has occurred between the UL phase and the grounding point on the ULN phase side of the open delta secondary circuit. The open circuit indicator light and the alarm indicator light will illuminate. When the voltage between any phase and the ULN phase is less than or equal to 40V, it is determined that an open circuit has occurred in the circuit after the grounding point on the ULN phase side of the open delta circuit. The open circuit indicator light and the alarm indicator light will illuminate.

[0005] The above method works only when the primary equipment is energized. When there is no power frequency voltage at the machine terminal (no energization), the method cannot effectively detect open circuits, resulting in a dead zone. Furthermore, current protection devices lack open-delta PT circuit open circuit detection technology, making the above method impractical for existing protection devices. Therefore, overcoming the shortcomings of existing technology is a pressing issue in the field of power system relay protection technology. Summary of the Invention

[0006] This disclosure aims to at least partially address one of the technical problems in the related art.

[0007] Therefore, one objective of this disclosure is to propose a real-time detection method for open delta circuit faults in voltage transformers.

[0008] The second objective of this disclosure is to provide a real-time detection device for open delta circuit faults in voltage transformers.

[0009] The third objective of this disclosure is to propose an electronic device.

[0010] The fourth objective of this disclosure is to provide a non-transitory computer-readable storage medium.

[0011] The fifth objective of this disclosure is to provide a computer program product.

[0012] To achieve the above objectives, the first aspect of this disclosure provides a real-time detection method for open-delta circuit faults of voltage transformers, comprising: applying a detection voltage to the generator neutral point grounding transformer when the generator is not operating; detecting electrical data of the open-delta circuit of the voltage transformer coupled to the generator terminals via the generator neutral point grounding transformer; and determining the operating state of the open-delta circuit of the voltage transformer at the generator terminals based on the electrical data.

[0013] According to one embodiment of this disclosure, determining the operating state of the open delta circuit of the voltage transformer at the generator terminal based on the electrical data includes: determining the operating state of the open delta circuit of the voltage transformer to be normal in response to the phase voltage being the same as the detected voltage, the phase-to-phase voltage being 0, and the voltage amplitude being the same as the amplitude of the detected voltage; or, determining the operating state of the open delta circuit of the voltage transformer to be open-circuit in response to the phase voltage being the same as the detected voltage, the phase-to-phase voltage being 0, and the voltage amplitude being different from the amplitude of the detected voltage.

[0014] According to one embodiment of this disclosure, determining that the phase voltage loop of the open delta circuit of the voltage transformer detects a phase voltage that is the same as the detected voltage includes: comparing the A-phase voltage, B-phase voltage, and C-phase voltage of the open delta circuit of the voltage transformer with a first voltage threshold; and determining that the phase voltage loop of the open delta circuit of the voltage transformer detects a phase voltage that is the same as the detected voltage in response to the fact that the A-phase voltage, the B-phase voltage, and the C-phase voltage are all greater than the first voltage threshold.

[0015] According to one embodiment of this disclosure, determining that the voltage amplitude of the open delta circuit of the voltage transformer is different from the amplitude of the detected voltage includes: comparing the winding voltage of the open delta circuit of the voltage transformer with a second voltage threshold; and determining that the voltage amplitude of the open delta circuit of the voltage transformer is different from the amplitude of the detected voltage in response to the winding voltage being less than the second voltage threshold.

[0016] According to one embodiment of this disclosure, the first voltage threshold is the product of the phase voltage when the open delta circuit of the voltage transformer is in normal operating state and the first parameter, and the second voltage threshold is the product of the phase voltage when the open delta circuit of the voltage transformer is in normal operating state and the second parameter.

[0017] According to one embodiment of this disclosure, a fault alarm is triggered in response to the open delta circuit of the voltage transformer being in an open-circuit state.

[0018] To achieve the above objectives, a second aspect of this disclosure provides a real-time detection device for open-delta circuit faults of voltage transformers, comprising: a loading module for loading a detection voltage onto the generator neutral point grounding transformer when the generator is not operating; a detection module for detecting electrical data of the open-delta circuit of the voltage transformer coupled to the generator terminals via the generator neutral point grounding transformer; and a determination module for determining the operating state of the open-delta circuit of the voltage transformer at the generator terminals based on the electrical data.

[0019] To achieve the above objectives, a third aspect of this disclosure provides an electronic device, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to implement the real-time detection method for open delta circuit open faults of voltage transformers as described in the first aspect of this disclosure.

[0020] To achieve the above objectives, a fourth aspect of this disclosure provides a non-transient computer-readable storage medium storing computer instructions, wherein the computer instructions are used to implement the real-time detection method for open delta circuit open faults of voltage transformers as described in the first aspect of this disclosure.

[0021] To achieve the above objectives, a fifth aspect of this disclosure provides a computer program product, including a computer program that, when executed by a processor, implements the real-time detection method for open delta circuit open faults of voltage transformers as described in the first aspect of this disclosure.

[0022] This disclosure describes a method for detecting the operating status of the open delta circuit of a voltage transformer by applying a detection voltage to the neutral point grounding transformer when the generator is not operating. This method can eliminate the dead zone in the open delta circuit detection of the voltage transformer when the generator is off, and is highly practical. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a real-time detection method for open delta circuit open faults of a voltage transformer according to one embodiment of this disclosure.

[0024] Figure 2 This is a schematic diagram of the open delta circuit disconnection detection principle for a voltage transformer (PT).

[0025] Figure 3 This is a schematic diagram of another method for real-time detection of open delta circuit open faults in voltage transformers according to one embodiment of this disclosure.

[0026] Figure 4 This is a schematic diagram of a real-time detection device for open delta circuit open faults of a voltage transformer according to one embodiment of the present disclosure.

[0027] Figure 5 This is a schematic diagram of an electronic device according to one embodiment of the present disclosure. Detailed Implementation

[0028] Embodiments of this disclosure are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this disclosure, and should not be construed as limiting this disclosure.

[0029] Figure 1 This is a schematic diagram of an exemplary embodiment of a real-time detection method for open delta circuit open faults in voltage transformers proposed in this disclosure, as shown below. Figure 1 As shown, the real-time detection method for open-delta circuit faults in voltage transformers includes the following steps:

[0030] S101, when the generator is not working, applies the detection voltage to the generator neutral point grounding transformer.

[0031] The real-time detection method for open delta circuit open faults of voltage transformers according to the embodiments of this application can be applied to the scenario of generator voltage transformer detection. The execution subject of the real-time detection of open delta circuit open faults of voltage transformers according to the embodiments of this application can be the real-time detection device for open delta circuit open faults of voltage transformers according to the embodiments of this application. The real-time detection device for open delta circuit open faults of voltage transformers can be installed on electronic equipment.

[0032] It should be noted that the preset frequency of the detection voltage is pre-set and can be changed according to actual design needs; no limitations are imposed here. For example, the set frequency can be 20Hz.

[0033] In one possible implementation of this disclosure, Figure 2This is a schematic diagram of the open delta circuit disconnection detection principle for a voltage transformer (PT), such as... Figure 2 As shown, PT1 and PT2 are generator terminal PTs, including two sets of three-phase windings and one set of open delta windings. Up is the dedicated power supply for the injection-type stator grounding protection device, which is used to generate the detection voltage. FZB is the generator neutral point grounding transformer, and G is the generator.

[0034] like Figure 2 As shown, after Up generates the detection voltage, the detection voltage is applied to the open delta circuit of the voltage transformer of PT.

[0035] S102 detects the electrical data of the open delta circuit of the voltage transformer coupled to the generator terminals via the generator neutral point grounding transformer.

[0036] In the embodiments disclosed herein, electrical data may include a variety of information, which are not limited herein. For example, it may include the phase voltage of the phase voltage loop of the voltage transformer in the open delta circuit of the voltage transformer, the phase voltage of the phase-to-phase loop, the voltage amplitude and the voltage phase, etc., which are not limited herein and may be limited according to the actual design needs.

[0037] S103, based on electrical data, determine the operating state of the open delta circuit of the voltage transformer at the generator terminal.

[0038] In this embodiment of the disclosure, after obtaining electrical data, the operating state of the open delta circuit of the voltage transformer at the generator terminal can be determined by analyzing the electrical data.

[0039] It should be noted that there are various analytical methods available, and no specific limitations are imposed here.

[0040] Optionally, the working state can be determined by a preset judgment rule, which is a pre-defined mapping relationship between electrical data and state. The corresponding working state is determined by comparing the electrical data with the judgment rule.

[0041] Alternatively, the operating state can be determined by inputting electrical data into a state determination model. This state determination model is pre-trained and stored in the electronic device's storage space for easy retrieval when needed.

[0042] In this embodiment, when the generator is not operating, a detection voltage is applied to the generator neutral point grounding transformer. Then, the electrical data of the open delta circuit of the voltage transformer coupled to the generator terminals via the generator neutral point grounding transformer is detected. Finally, based on the electrical data, the operating state of the open delta circuit of the voltage transformer at the generator terminals is determined. This disclosure eliminates the dead zone in the open delta circuit disconnection detection when the generator is not operating by applying a detection voltage to the neutral point grounding transformer to detect the operating state of the open delta circuit of the voltage transformer. This method is highly practical.

[0043] It should be noted that a fault alarm will be triggered in response to the open delta circuit of the voltage transformer being in an open state.

[0044] In the above embodiments, the electrical data includes the phase voltage of the phase voltage loop of the voltage transformer in the open delta circuit, the phase voltage of the phase-to-phase loop, and the voltage amplitude, which determines the operating state of the open delta circuit of the voltage transformer at the generator terminal.

[0045] S301, in response to the phase voltage being the same as the detected voltage, the phase-to-phase voltage being 0, and the voltage amplitude being the same as the detected voltage amplitude, determines that the operating state of the open delta circuit of the voltage transformer is normal.

[0046] S302, in response to the phase voltage being the same as the detected voltage, the phase-to-phase voltage being 0, and the voltage amplitude being different from the detected voltage amplitude, determines that the operating state of the open delta circuit of the voltage transformer is the open-circuit state.

[0047] It should be noted that if the phase voltage is the same as the detected voltage and the phase-to-phase voltage is 0, it indicates that the open delta circuit of the voltage transformer has received the detected voltage normally. When the voltage amplitude is the same as the detected voltage amplitude, it indicates that the open delta circuit of the voltage transformer is operating normally. If they are not the same, it indicates that the open delta circuit of the voltage transformer is in an open-circuit state. See the table below for details:

[0048]

[0049] In the above embodiments, to determine that the voltage transformer phase voltage loop of the open delta circuit of the voltage transformer has detected a phase voltage that is the same as the detected voltage, the A-phase voltage, B-phase voltage and C-phase voltage of the open delta circuit of the voltage transformer can be compared with a first voltage threshold respectively. In response to the fact that the A-phase voltage, B-phase voltage and C-phase voltage are all greater than the first voltage threshold, it is determined that the voltage transformer phase voltage loop of the open delta circuit of the voltage transformer has detected a phase voltage that is the same as the detected voltage.

[0050] To determine that the voltage amplitude of the open delta circuit of a voltage transformer is different from the amplitude of the detected voltage, the winding voltage of the open delta circuit of the voltage transformer can be compared with a second voltage threshold first. Then, in response to the winding voltage being less than the second voltage threshold, it can be determined that the voltage amplitude of the open delta circuit of the voltage transformer is different from the amplitude of the detected voltage.

[0051] In one possible implementation of this disclosure, taking a detection voltage of 20Hz as an example, the working state can be determined to be in the disconnection state by the following formula.

[0052]

[0053] Among them, U a20HZ The 20Hz voltage of phase A on the secondary side of the PT measured by the protection device, U b20HZ The 20Hz voltage of phase B on the secondary side of the PT measured by the protection device, U c20HZ The 20Hz voltage of phase C on the secondary side of the PT measured by the protection device, U L20HZ The voltage U measured by the protection device on the PT secondary open delta winding at 20Hz set1 U is the first voltage threshold. set2 This is the second voltage threshold.

[0054] It should be noted that the first and second voltage thresholds are preset and can be changed according to actual design needs; no restrictions are imposed here.

[0055] In one possible implementation of this disclosure, the first voltage threshold is the product of the phase voltage of the open delta circuit of the voltage transformer in normal operating state and the first parameter, and the second voltage threshold is the product of the phase voltage of the open delta circuit of the voltage transformer in normal operating state and the second parameter.

[0056] In one possible implementation of this disclosure, the first parameter can be a number between 0.7 and 0.8, and the second parameter can be a fraction of the first parameter. times.

[0057] Corresponding to the real-time detection methods for open delta circuit open faults of voltage transformers provided in the above embodiments, one embodiment of this disclosure also provides a real-time detection device for open delta circuit open faults of voltage transformers. Since the real-time detection device for open delta circuit open faults of voltage transformers provided in this disclosure corresponds to the real-time detection methods for open delta circuit open faults of voltage transformers provided in the above embodiments, the implementation methods of the above-mentioned real-time detection methods for open delta circuit open faults of voltage transformers are also applicable to the real-time detection device for open delta circuit open faults of voltage transformers provided in this disclosure, and will not be described in detail in the following embodiments.

[0058] Figure 4 This is a schematic diagram of a real-time detection device for open delta circuit open faults of voltage transformers proposed in this disclosure, as shown below. Figure 4 As shown, the real-time detection device 400 for open delta circuit fault of voltage transformer includes: a loading module 410, a detection module 420 and a determination module 430.

[0059] The loading module 410 is used to apply the detected voltage to the generator neutral point grounding transformer when the generator is not working.

[0060] The detection module 420 is used to detect the electrical data of the open delta circuit of the voltage transformer coupled to the generator terminal through the generator neutral point grounding transformer.

[0061] Module 430 is used to determine the operating state of the open delta circuit of the voltage transformer at the generator terminals based on electrical data.

[0062] In one embodiment of this disclosure, the electrical data includes the phase voltage of the phase voltage loop of the voltage transformer in the open delta circuit, the phase voltage of the phase-to-phase loop, and the voltage amplitude. The determining module 430 is further configured to: determine that the operating state of the open delta circuit of the voltage transformer is normal in response to the phase voltage being the same as the detected voltage, the phase-to-phase voltage being 0, and the voltage amplitude being the same as the amplitude of the detected voltage; or, determine that the operating state of the open delta circuit of the voltage transformer is open-circuit in response to the phase voltage being the same as the detected voltage, the phase-to-phase voltage being 0, and the voltage amplitude being different from the amplitude of the detected voltage.

[0063] In one embodiment of this disclosure, the determining module 430 is further configured to: compare the A-phase voltage, B-phase voltage, and C-phase voltage of the open delta circuit of the voltage transformer with a first voltage threshold; and, in response to the fact that the A-phase voltage, B-phase voltage, and C-phase voltage are all greater than the first voltage threshold, determine that the voltage transformer phase voltage loop of the open delta circuit of the voltage transformer has detected a phase voltage that is the same as the detected voltage.

[0064] In one embodiment of this disclosure, the determining module 430 is further configured to: compare the winding voltage of the open delta circuit of the voltage transformer with a second voltage threshold; and determine that the voltage amplitude of the open delta circuit of the voltage transformer is different from the amplitude of the detected voltage in response to the winding voltage being less than the second voltage threshold.

[0065] In one embodiment of this disclosure, the first voltage threshold is the product of the phase voltage when the open delta circuit of the voltage transformer is in normal operating state and the first parameter, and the second voltage threshold is the product of the phase voltage when the open delta circuit of the voltage transformer is in normal operating state and the second parameter.

[0066] In one embodiment of this disclosure, the determining module 430 is further configured to: perform a fault alarm in response to the operating state of the open delta circuit of the voltage transformer being in an open state.

[0067] This disclosure describes a method for detecting the operating status of the open delta circuit of a voltage transformer by applying a detection voltage to the neutral point grounding transformer when the generator is not operating. This method can eliminate the dead zone in the open delta circuit detection of the voltage transformer when the generator is off, and is highly practical.

[0068] To implement the above embodiments, this disclosure also proposes an electronic device 500, such as... Figure 5 As shown, the electronic device 500 includes a processor 501 and a memory 502 communicatively connected to the processor. The memory 502 stores instructions that can be executed by at least one processor. The instructions are executed by at least one processor 501 to implement the real-time detection method for open delta circuit open faults of voltage transformers as described in the first aspect embodiment of this disclosure.

[0069] To implement the above embodiments, this disclosure also proposes a non-transient computer-readable storage medium storing computer instructions, wherein the computer instructions are used to enable a computer to implement a real-time detection method for open delta circuit open faults of voltage transformers as described in the first aspect of this disclosure.

[0070] To implement the above embodiments, this disclosure also proposes a computer program product, including a computer program that, when executed by a processor, implements a real-time detection method for open delta circuit open faults of voltage transformers as described in the first aspect of this disclosure.

[0071] In the description of this disclosure, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this disclosure and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure.

[0072] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this disclosure, "a plurality of" means two or more, unless otherwise expressly specified.

[0073] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0074] Although embodiments of the present disclosure have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A method for real-time detection of open-delta circuit faults in voltage transformers, characterized in that, include: When the generator is not working, the detection voltage is applied to the generator neutral point grounding transformer; Detect the electrical data of the open delta circuit of the voltage transformer coupled to the generator terminals via the generator neutral point grounding transformer; Based on the electrical data, determine the operating state of the open delta circuit of the voltage transformer at the generator terminal; The electrical data includes the phase voltage of the phase voltage loop of the voltage transformer in the open delta circuit of the voltage transformer, the phase voltage of the phase-to-phase loop, and the voltage amplitude, determining the operating state of the open delta circuit of the voltage transformer at the generator terminal, including: In response to the phase voltage being the same as the detected voltage, the phase-to-phase voltage being 0, and the voltage amplitude being the same as the detected voltage amplitude, the operating state of the open delta circuit of the voltage transformer is determined to be normal; or, In response to the phase voltage being the same as the detected voltage, the phase-to-phase voltage being 0, and the voltage amplitude being different from the amplitude of the detected voltage, the operating state of the open delta circuit of the voltage transformer is determined to be the open-circuit state. Determining whether the phase voltage loop of the open delta circuit of the voltage transformer detects a phase voltage that is the same as the detected voltage includes: The voltages of phase A, phase B, and phase C of the open delta circuit of the voltage transformer are compared with the first voltage threshold. In response to the fact that the voltage of phase A, the voltage of phase B, and the voltage of phase C are all greater than the first voltage threshold, it is determined that the voltage transformer phase voltage loop of the open delta circuit of the voltage transformer has detected a phase voltage that is the same as the detected voltage; Determining that the voltage amplitude of the open delta circuit of the voltage transformer is different from the amplitude of the detected voltage includes: The winding voltage of the open delta circuit of the voltage transformer is compared with the second voltage threshold. In response to the winding voltage being less than the second voltage threshold, it is determined that the voltage amplitude of the open delta circuit of the voltage transformer is different from the amplitude of the detected voltage.

2. The method according to claim 1, characterized in that, The first voltage threshold is the product of the phase voltage when the open delta circuit of the voltage transformer is in normal operating condition and the first parameter, and the second voltage threshold is the product of the phase voltage when the open delta circuit of the voltage transformer is in normal operating condition and the second parameter.

3. The method according to any one of claims 1-2, characterized in that, The method further includes: A fault alarm is triggered in response to the open delta circuit of the voltage transformer being in an open-circuit state.

4. A real-time detection device for open delta circuit faults in voltage transformers, characterized in that, The apparatus implements the method as described in claim 1, the apparatus comprising: The loading module is used to apply the detected voltage to the generator neutral grounding transformer when the generator is not working. The detection module is used to detect the electrical data of the open delta circuit of the voltage transformer coupled to the generator terminals via the generator neutral point grounding transformer; The determination module is used to determine the operating state of the open delta circuit of the voltage transformer at the generator terminal based on the electrical data.

5. An electronic device, characterized in that, Including memory and processor; The processor reads executable program code stored in the memory to run a program corresponding to the executable program code, so as to implement the method as described in any one of claims 1-3.

6. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method as described in any one of claims 1-3.

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