Transformer overvoltage monitoring method, system and electronic equipment

Abstract

The present invention discloses a transformer overvoltage monitoring method, system and electronic equipment, and relates to the field of transformer detection technology. After determining the iron core signal transfer function of the transformer by testing the overvoltage waveform and the iron core grounding current waveform, the method determines the amplitude-frequency characteristics of the voltage signal of the transformer based on the iron core signal transfer function and the iron core grounding current of the transformer in the overvoltage state obtained during the operation of the transformer, so as to determine the overvoltage waveform suffered by the transformer, and finally obtain the overvoltage state of the transformer based on the overvoltage waveform. Thus, the problem of misjudgment in transformer overvoltage monitoring is solved because the electromagnetic mutual inductor has low effectiveness in overvoltage monitoring and cannot present the full picture of transformer overvoltage, and thus the problem of misjudgment is easily caused in transformer overvoltage monitoring is solved, and the overvoltage waveform suffered by the transformer winding is inverted by the iron core grounding current waveform of the transformer in actual operation, thereby improving the accuracy of transformer overvoltage monitoring.

Description

Technical Field

[0001] The present invention relates to the technical field of transformer detection, and more specifically, to a transformer overvoltage monitoring method, system and electronic equipment. Background Art

[0002] Transformers are key components in power systems, and their health status directly affects the stable operation of power systems. However, when a transmission line is subjected to overvoltage, the overvoltage steep wave will be transmitted along the transmission line. When the overvoltage reaches the neutral point at the end of the step-up transformer coil, full wave reflection will occur, causing the transmission wave to be superimposed, doubling the overvoltage suffered by the transformer, which can easily cause transformer insulation breakdown and threaten equipment safety. Therefore, timely detection of transformer overvoltage can effectively avoid further losses.

[0003] At present, electromagnetic voltage transformers are mainly used to monitor the system voltage of equipment. However, the effectiveness of electromagnetic voltage transformers in overvoltage monitoring is low, and they cannot present the full picture of transformer overvoltage, which is prone to misjudgment. Summary of the invention

[0004] The purpose of the present invention is to provide a transformer overvoltage monitoring method, system and electronic equipment to solve the problem that the electromagnetic transformer has low effectiveness in overvoltage monitoring and cannot present the full picture of transformer overvoltage, so it is easy to make misjudgments during transformer overvoltage monitoring. The overvoltage waveform suffered by the transformer winding can be inverted by using the core grounding current waveform of the transformer in actual operation, thereby improving the accuracy of transformer overvoltage monitoring.

[0005] In a first aspect, the present invention provides a transformer overvoltage monitoring method, comprising:

[0006] Obtaining a target current, wherein the target current is a core grounding current of the transformer under an overvoltage state obtained during operation of the transformer;

[0007] Determining the amplitude-frequency characteristic of the voltage signal of the transformer based on the target current and the iron core signal transfer function of the transformer;

[0008] Wherein, the core signal transfer function is determined by a test overvoltage waveform and a test core grounding current waveform obtained when an overvoltage test is performed on the transformer;

[0009] Determining the overvoltage waveform of the transformer based on the amplitude-frequency characteristic of the voltage signal;

[0010] Based on the overvoltage waveform, an overvoltage state of the transformer is acquired.

[0011] In a preferred solution, obtaining the target current includes:

[0012] monitoring the core grounding current of the transformer;

[0013] Determine whether the core grounding current meets preset conditions, wherein the preset conditions are: the frequency is greater than a preset frequency, the amplitude is greater than a preset amplitude, and it is a pulse current;

[0014] The core grounding current that meets the preset condition is used as the target current.

[0015] In a preferred solution, the method for determining the core signal transfer function includes:

[0016] Obtaining the test overvoltage waveform and the test core grounding current waveform;

[0017] Performing frequency domain transformation on the test overvoltage waveform and the test core grounding current waveform respectively to obtain test amplitude-frequency characteristics of the test overvoltage waveform and the test core grounding current waveform;

[0018] Based on the test amplitude-frequency characteristics of the test overvoltage waveform and the test iron core grounding current waveform, obtaining the iron core frequency response characteristic function;

[0019] The core signal transfer function is determined based on the core frequency response characteristic function.

[0020] In a preferred solution, determining the amplitude-frequency characteristic of the voltage signal of the transformer based on the target current and the core signal transfer function of the transformer includes:

[0021] Based on the target current, acquiring an amplitude-frequency characteristic of the target current;

[0022] Based on the amplitude-frequency characteristic of the target current and the core signal transfer function, the amplitude-frequency characteristic of the voltage signal of the transformer is determined.

[0023] In a preferred solution, determining the waveform of the voltage applied to the transformer based on the amplitude-frequency characteristic of the voltage signal includes:

[0024] The amplitude-frequency characteristic of the voltage signal is transformed in the time domain to obtain the waveform of the voltage received by the transformer.

[0025] In a second aspect, the present invention provides a transformer overvoltage monitoring system, comprising:

[0026] A collection unit, used to obtain a target current, wherein the target current is a core grounding current of the transformer under an overvoltage state obtained during the operation of the transformer;

[0027] A first processing unit, configured to determine an amplitude-frequency characteristic of a voltage signal of the transformer based on the target current and a core signal transfer function of the transformer;

[0028] Wherein, the core signal transfer function is determined by a test overvoltage waveform and a test core grounding current waveform obtained when an overvoltage test is performed on the transformer;

[0029] a second processing unit, for determining an overvoltage waveform received by the transformer based on the amplitude-frequency characteristic of the voltage signal;

[0030] A state determination unit is used to obtain the overvoltage state of the transformer based on the overvoltage waveform.

[0031] In a preferred solution, the acquisition unit is specifically used for:

[0032] Monitor the core grounding current of the transformer; determine whether the core grounding current meets preset conditions, wherein the preset conditions are: the frequency is greater than the preset frequency, the amplitude is greater than the preset amplitude, and it is a pulse current; and use the core grounding current that meets the preset conditions as the target current.

[0033] In a preferred embodiment, the transformer overvoltage monitoring system provided by the present invention further includes:

[0034] The third processing unit is used to obtain the test overvoltage waveform and the test core grounding current waveform; perform frequency domain transformation on the test overvoltage waveform and the test core grounding current waveform respectively to obtain the test amplitude-frequency characteristics of the test overvoltage waveform and the test core grounding current waveform; obtain the core frequency response characteristic function based on the test amplitude-frequency characteristics of the test overvoltage waveform and the test core grounding current waveform; and determine the core signal transfer function based on the core frequency response characteristic function.

[0035] In a preferred solution, the first processing unit is specifically used to obtain the amplitude-frequency characteristic of the target current based on the target current; and determine the amplitude-frequency characteristic of the voltage signal of the transformer based on the amplitude-frequency characteristic of the target current and the core signal transfer function.

[0036] In a third aspect, the present invention provides an electronic device, the electronic device comprising:

[0037] processor;

[0038] a memory for storing instructions executable by the processor;

[0039] The processor is used to execute the transformer overvoltage monitoring method provided in the first aspect of the present invention.

[0040] In order to achieve the above-mentioned purpose, the transformer overvoltage monitoring method, system and electronic device provided by the present invention obtain the core grounding current of the transformer in the overvoltage state as the target current during the operation of the transformer, and then determine the amplitude-frequency characteristic of the voltage signal of the transformer based on the target current and the core signal transfer function, and the core signal transfer function is determined by the test overvoltage waveform and the test core grounding current waveform obtained when the transformer is subjected to an overvoltage test, so that after determining the amplitude-frequency characteristic of the voltage signal of the transformer, the overvoltage waveform suffered by the transformer can be determined based on the amplitude-frequency characteristic of the voltage signal; finally, the overvoltage state of the transformer is obtained based on the overvoltage waveform. That is, by utilizing the characteristic that the core signal transfer function of the same transformer remains unchanged, starting from the core grounding current of the transformer when it is subjected to overvoltage, the overvoltage condition of the transformer is judged by monitoring the inverted voltage waveform, and then the overvoltage waveform suffered by the incoming line end of the transformer winding can be observed more intuitively, thereby improving the accuracy of monitoring the overvoltage condition of the transformer winding line end. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A flow chart of a transformer overvoltage monitoring method provided for the implementation of the present invention.

[0042] Figure 2 A flow chart of a method for determining a core signal transfer function by testing an overvoltage waveform and a core grounding current waveform provided for the implementation of the present invention.

[0043] Figure 3 A structural diagram of a transformer overvoltage monitoring system provided in an embodiment of the present invention.

[0044] Figure 4 A structural diagram of another transformer overvoltage monitoring system provided in an embodiment of the present invention.

[0045] Figure 5 A schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0046] The present invention is further described in detail below through the accompanying drawings and specific embodiments.

[0047] At present, the overvoltage situation suffered by the transformer is usually monitored based on the recording method. It is understandable that the detection frequency band of the recording method using electromagnetic current transformers, voltage transformers, etc. is relatively low, and the high-frequency response of the recording method using capacitive voltage transformers is also poor, and the overvoltage can only be warned through the sudden change of the signal. Therefore, it may not be able to truly reflect the overvoltage situation of the transformer winding line end, that is, the effectiveness of overvoltage monitoring is low, and it cannot present the full picture of the transformer overvoltage.

[0048] In order to solve the above problems, the present invention provides a transformer overvoltage monitoring method for monitoring transformer winding overvoltage by measuring the core grounding current of the transformer when it is subjected to overvoltage and inverting the overvoltage waveform suffered by the transformer corresponding to the current waveform.

[0049] The transformer overvoltage monitoring method provided by the present invention is executed on an electronic device, which may be a controller of the transformer, or other controllers independent of the transformer, or an intelligent terminal device such as a laptop, a personal computer, and a tablet computer that can communicate with the crane control system. Of course, in some cases, it may also be a server on the network side.

[0050] like Figure 1 As shown, the transformer overvoltage monitoring method provided by the embodiment of the present invention mainly includes the following steps:

[0051] 110. Obtain target current.

[0052] The target current is the core grounding current of the transformer under an overvoltage state obtained during the operation of the transformer.

[0053] It is understandable that currently commonly used transformers are all provided with a core grounding copper bar. The working current on the core grounding copper bar is the core grounding current of the transformer.

[0054] Furthermore, under normal conditions, the core grounding current of the transformer has a low frequency, a small amplitude, and is periodic, while when the transformer is subjected to overvoltage, the core grounding current has an increased frequency, a larger amplitude, and a pulse characteristic.

[0055] Based on this, in an optional embodiment, obtaining the target current includes:

[0056] Monitor the transformer core grounding current;

[0057] Determine whether the core grounding current meets preset conditions, the preset conditions being: the frequency is greater than a preset frequency, the amplitude is greater than a preset amplitude, and it is a pulse current;

[0058] The core grounding current that meets the preset conditions is used as the target current.

[0059] The preset frequency and the preset amplitude are preset based on experience or experiments, and are not specifically limited here. In this embodiment, during the operation of the transformer, the working current on the core grounding copper bar of the transformer can be sensed by a current transformer, and then the controller is connected to the current transformer for communication, so that the controller can obtain the target current of the transformer.

[0060] 120. Based on the target current and the iron core signal transfer function of the transformer, determine the amplitude-frequency characteristic of the voltage signal of the transformer.

[0061] The core signal transfer function is determined by the test overvoltage waveform and the test core grounding current waveform obtained when the transformer is subjected to an overvoltage test.

[0062] Specifically, the iron core signal transfer function of the same transformer is unchanged. Based on this, after the iron core signal transfer function of the transformer is determined based on the test overvoltage waveform and the test iron core grounding current waveform obtained when the transformer to be monitored is subjected to an overvoltage test, the amplitude-frequency characteristics of the voltage signal of the transformer can be obtained by combining the target current of the transformer obtained and the iron core signal transfer function of the transformer during the actual operation of the transformer.

[0063] In an optional embodiment, a method for determining the core signal transfer function by using a test overvoltage waveform and a test core grounding current waveform obtained when performing an overvoltage test on a transformer is specifically described, that is, Figure 2 As shown, the following steps are included:

[0064] 210. Obtain the test overvoltage waveform and the test core grounding current waveform;

[0065] 220. Perform frequency domain transformation on the test overvoltage waveform and the test core grounding current waveform respectively to obtain the test amplitude-frequency characteristics of the test overvoltage waveform and the test core grounding current waveform;

[0066] 230. Based on the test amplitude-frequency characteristics of the test overvoltage waveform and the test core grounding current waveform, obtain the core frequency response characteristic function;

[0067] 240. Determine the core signal transfer function based on the core frequency response characteristic function.

[0068] In this embodiment, by performing an overvoltage test on the transformer to be monitored for overvoltage, the overvoltage waveform U(t) suffered by the transformer winding and the transformer core grounding current waveform I(t) can be measured and recorded during the test.

[0069] Furthermore, by performing frequency domain transformation on the overvoltage waveform U(t) suffered by the transformer winding and the core grounding current waveform I(t) of the transformer, the amplitude-frequency characteristic U(w) of the overvoltage waveform U(t) suffered by the transformer winding and the amplitude-frequency characteristic I(w) of the core grounding current waveform I(t) of the transformer can be obtained respectively.

[0070] Furthermore, based on the amplitude-frequency characteristics U(w) and I(w), the core frequency response characteristic function G(w) can be calculated as shown in formula (1):

[0071] G(w)=I(w) / U(w) (1)

[0072] Finally, the core signal transfer function G(s) can be calculated from the core frequency response characteristic curve G(w):

[0073] G(s)=1 / G(w) (2)

[0074] That is, the core signal transfer function G(s) is determined by the amplitude-frequency characteristics of the overvoltage waveform and the core grounding current waveform when the transformer is subjected to overvoltage. However, during the operation of the transformer, the controller obtains the core grounding current of the transformer, rather than the amplitude-frequency characteristics of the core grounding current waveform. When determining the voltage signal received by the transformer based on the core grounding current, the amplitude-frequency characteristics of the core grounding current must also be determined first.

[0075] Based on this, in an optional embodiment, a method for determining the amplitude-frequency characteristic of the voltage signal of the transformer based on the target current and the iron core signal transfer function of the transformer is specifically described, that is:

[0076] Based on the target current, an amplitude-frequency characteristic of the target current is obtained;

[0077] Based on the amplitude-frequency characteristic of the target current and the core signal transfer function, the amplitude-frequency characteristic of the voltage signal of the transformer is determined.

[0078] In this embodiment, during the operation of the transformer, the target current If(t) of the transformer is converted into the amplitude-frequency characteristic If(w) of the target current, which is used as input and input into the core signal transfer function G(s). Then, the amplitude-frequency characteristic Uf(w) of the voltage signal received by the transformer can be calculated through the core signal transfer function G(s).

[0079] 130. Based on the amplitude-frequency characteristics of the voltage signal, determine the overvoltage waveform of the transformer.

[0080] Specifically, after the amplitude-frequency characteristic Uf(w) of the transformer voltage signal is determined based on the core signal transfer function G(s) and the target current If(t) during transformer operation, the overvoltage waveform Uf(t) exerted on the transformer can be obtained based on the inversion of the amplitude-frequency characteristic Uf(w) of the voltage signal.

[0081] 140. Based on the overvoltage waveform, obtain the overvoltage state of the transformer.

[0082] In an optional embodiment, a method for determining the waveform of the voltage received by the transformer based on the amplitude-frequency characteristic of the voltage signal is specifically described, namely:

[0083] The amplitude-frequency characteristics of the voltage signal are transformed in the time domain to obtain the overvoltage waveform of the transformer.

[0084] The transformer overvoltage monitoring method provided by the above-mentioned embodiment of the present invention is based on the characteristic that the iron core signal transfer function of the same transformer remains unchanged. After the iron core signal transfer function of the transformer is determined based on an overvoltage test on the transformer, the port overvoltage of the transformer winding is inverted by using the working current on the iron core grounding copper busbar. Compared with the currently commonly used recording method, the overvoltage waveform suffered by the incoming end of the transformer winding can be more intuitively observed, which is more conducive to judging the overvoltage situation of the transformer port, that is, the high-frequency signal of the iron core grounding current of the transformer is used to accurately monitor the overvoltage of the transformer winding.

[0085] The transformer overvoltage monitoring system provided in an embodiment of the present invention is introduced below. The transformer overvoltage monitoring system described below can be considered as a module architecture for implementing the transformer overvoltage monitoring method provided in an embodiment of the present invention; the content described below can be cross-referenced with the above.

[0086] Optional, see Figure 3 , Figure 3 : is a structural block diagram of a transformer overvoltage monitoring system provided by an embodiment of the present invention, and the system may include:

[0087] The acquisition unit 10 is used to obtain a target current, where the target current is the core grounding current of the transformer under an overvoltage state obtained during the operation of the transformer;

[0088] A first processing unit 20, configured to determine an amplitude-frequency characteristic of a voltage signal of the transformer based on a target current and a core signal transfer function of the transformer;

[0089] The core signal transfer function is determined by the test overvoltage waveform and the test core grounding current waveform obtained when the transformer is subjected to an overvoltage test;

[0090] The second processing unit 30 determines the overvoltage waveform of the transformer based on the amplitude-frequency characteristic of the voltage signal;

[0091] The state determination unit 40 is used to obtain the overvoltage state of the transformer based on the overvoltage waveform.

[0092] Optionally, the collection unit 10 is specifically used for:

[0093] Monitor the core grounding current of the transformer; determine whether the core grounding current meets preset conditions, the preset conditions are: the frequency is greater than the preset frequency, the amplitude is greater than the preset amplitude, and it is a pulse current; use the core grounding current that meets the preset conditions as the target current.

[0094] Optional, see Figure 4 , Figure 4FIG. 1 is a structural block diagram of another transformer overvoltage monitoring system provided by an embodiment of the present invention. Figure 3 Based on the embodiment shown, the system further includes:

[0095] The third processing unit 50 is used to obtain the test overvoltage waveform and the test core grounding current waveform; perform frequency domain transformation on the test overvoltage waveform and the test core grounding current waveform respectively to obtain the test amplitude-frequency characteristics of the test overvoltage waveform and the test core grounding current waveform; and obtain the core frequency response characteristic function based on the test amplitude-frequency characteristics of the test overvoltage waveform and the test core grounding current waveform.

[0096] Optionally, the first processing unit 20 is specifically used to obtain the amplitude-frequency characteristics of the core grounding current based on the core grounding current; determine the amplitude-frequency characteristics of the voltage signal of the transformer based on the amplitude-frequency characteristics of the core grounding current and the core signal transfer function; and determine the core signal transfer function based on the core frequency response characteristic function.

[0097] Optionally, the second processing unit 30 is specifically configured to perform a time domain transformation on the amplitude-frequency characteristic of the voltage signal to obtain a waveform of the voltage received by the transformer.

[0098] Below, reference Figure 5 To describe the electronic device provided by the embodiment of the present application, the electronic device provided by the embodiment may include: at least one processor 100, at least one communication interface 200, at least one memory 300 and at least one communication bus 400;

[0099] In the embodiment of the present invention, the number of the processor 100, the communication interface 200, the memory 300, and the communication bus 400 is at least one, and the processor 100, the communication interface 200, and the memory 300 communicate with each other through the communication bus 400; obviously, Figure 5 The communication connections shown for the processor 100, the communication interface 200, the memory 300, and the communication bus 400 are merely optional;

[0100] Optionally, the communication interface 200 may be an interface of a communication module, such as an interface of a GSM module; the processor 100 may be a central processing unit CPU, or an application specific integrated circuit ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of the present invention.

[0101] The memory 300 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0102] The processor 100 is specifically used to execute the application program in the memory to implement the steps of the above-mentioned crane hoisting wire rope installation control method.

[0103] The above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A transformer overvoltage monitoring method, characterized in that: include: Obtaining a target current, wherein the target current is a core grounding current of the transformer under an overvoltage state obtained during operation of the transformer; Based on the target current and the iron core signal transfer function of the transformer, the amplitude-frequency characteristic of the voltage signal of the transformer is determined; wherein the iron core signal transfer function is determined by a test overvoltage waveform and a test iron core grounding current waveform obtained when an overvoltage test is performed on the transformer; Determining the overvoltage waveform of the transformer based on the amplitude-frequency characteristic of the voltage signal; Based on the overvoltage waveform, acquiring an overvoltage state of the transformer; Wherein, the method for determining the core signal transfer function comprises: Obtaining the test overvoltage waveform and the test core grounding current waveform; Performing frequency domain transformation on the test overvoltage waveform and the test core grounding current waveform respectively to obtain test amplitude-frequency characteristics of the test overvoltage waveform and the test core grounding current waveform; Based on the test amplitude-frequency characteristics of the test overvoltage waveform and the test iron core grounding current waveform, obtaining an iron core frequency response characteristic function; The core signal transfer function is determined based on the core frequency response characteristic function.

2. The transformer overvoltage monitoring method according to claim 1, characterized in that: The obtaining of the target current comprises: Determine whether the core grounding current of the transformer meets preset conditions, wherein the preset conditions are: the frequency is greater than a preset frequency, the amplitude is greater than a preset amplitude, and it is a pulse current; The core grounding current that meets the preset condition is used as the target current.

3. The transformer overvoltage monitoring method according to claim 1, characterized in that: The step of determining the amplitude-frequency characteristic of the voltage signal of the transformer based on the target current and the iron core signal transfer function of the transformer comprises: Based on the target current, acquiring an amplitude-frequency characteristic of the target current; Based on the amplitude-frequency characteristic of the target current and the core signal transfer function, the amplitude-frequency characteristic of the voltage signal of the transformer is determined.

4. The transformer overvoltage monitoring method according to claim 1, characterized in that: The step of determining the overvoltage waveform of the transformer based on the amplitude-frequency characteristic of the voltage signal comprises: The amplitude-frequency characteristic of the voltage signal is transformed in the time domain to obtain the overvoltage waveform received by the transformer.

5. A transformer overvoltage monitoring system, characterized in that: include: A collection unit, used to obtain a target current, wherein the target current is a core grounding current of the transformer under an overvoltage state obtained during the operation of the transformer; a first processing unit, configured to determine the amplitude-frequency characteristic of the voltage signal of the transformer based on the target current and the iron core signal transfer function of the transformer, and to determine the iron core signal transfer function based on an iron core frequency response characteristic function; Wherein, the core signal transfer function is determined by a test overvoltage waveform and a test core grounding current waveform obtained when an overvoltage test is performed on the transformer; a second processing unit, for determining an overvoltage waveform received by the transformer based on the amplitude-frequency characteristic of the voltage signal; a state determination unit, configured to obtain an overvoltage state of the transformer based on the overvoltage waveform; Wherein, the system further comprises: The third processing unit is used to obtain the test overvoltage waveform and the test core grounding current waveform; perform frequency domain transformation on the test overvoltage waveform and the test core grounding current waveform respectively to obtain the test amplitude-frequency characteristics of the test overvoltage waveform and the test core grounding current waveform; and obtain the core frequency response characteristic function based on the test amplitude-frequency characteristics of the test overvoltage waveform and the test core grounding current waveform.

6. The transformer overvoltage monitoring system according to claim 5, characterized in that: The acquisition unit is specifically used for: Monitor the core grounding current of the transformer; determine whether the core grounding current meets preset conditions, wherein the preset conditions are: the frequency is greater than the preset frequency, the amplitude is greater than the preset amplitude, and it is a pulse current; and use the core grounding current that meets the preset conditions as the target current.

7. The transformer overvoltage monitoring system according to claim 5, characterized in that: The first processing unit is specifically used to obtain the amplitude-frequency characteristic of the target current based on the target current; and determine the amplitude-frequency characteristic of the voltage signal of the transformer based on the amplitude-frequency characteristic of the target current and the core signal transfer function.

8. An electronic device, characterized in that: The electronic device comprises: processor; a memory for storing instructions executable by the processor; The processor is used to execute the transformer overvoltage monitoring method described in any one of claims 1 to 4 above.

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