Wireless distributed transformer winding deformation diagnosis device

Abstract

The invention discloses a wireless distributed transformer winding deformation diagnosis device, which comprises a front-end sensing module, a wireless transmission module and an upper computer, and is characterized in that a shell of the front-end sensing module adopts a shielding shell, and an onboard low-power-consumption frequency sweeping test circuit is arranged in the front-end sensing module; rotary clamping pieces are arranged on the back face of the shell in pairs, a rotary handle is arranged on the shell, the rotary handle and the rotary clamping pieces form a ratchet wheel clamping mechanism, and the rotary handle is used for controlling the rotary clamping pieces to be opened and closed in the axial direction. Compared with the prior art, the integrated packaging structure is adopted, the shielding performance is good, use is convenient, battery power supply is achieved, power supply interference is eliminated, long-distance wiring is omitted through the ratchet wheel clamping mechanism, the detection accuracy and consistency are improved, and three-phase synchronous detection is achieved; meanwhile, an edge computing network formed by an upper computer and a plurality of front-end sensing modules can be established, the detection range is expanded, and the detection efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of transformer winding deformation detection, and particularly to a wireless distributed transformer winding deformation diagnosis device. Background Art

[0002] Power transformers are the core equipment of the power system. Due to deficiencies in early transformer design, short-circuit resistance calculation, transformer manufacturing and material selection, as well as a large number of foreign objects in the transmission channels near substations, the cumulative effect of multiple sudden short-circuit impacts on transformers has led to prominent problems of winding deformation faults. Its harms are mainly manifested in two aspects: When a transformer suddenly short-circuits, a large short-circuit current will be generated. Although the duration is short, before the circuit breaker has time to cut off, the transformer will be impacted by the short-circuit current, affecting thermal stability and possibly damaging the transformer; when a transformer suddenly short-circuits, the overcurrent will generate a large electrodynamic force, affecting dynamic stability, deforming the winding, damaging the winding insulation, and other components will also be damaged. If a transformer short-circuit fault occurs simultaneously with a substation protection or DC system failure fault, it often causes a vicious accident of transformer combustion and explosion. Such as transformer explosion, etc.

[0003] Transformer winding deformation is one of the important reasons for transformer damage accidents. Conventional electrical tests such as resistance measurement, ratio measurement, and capacitance measurement are difficult to detect winding deformation. The detection device cannot be connected near the winding measurement end, resulting in low detection accuracy and consistency, difficult power supply acquisition on-site, signal distortion during long-distance transmission, susceptibility to interference, cumbersome operation, low detection efficiency, and other adverse factors, all of which affect the safe operation of the power grid. Therefore, it is very necessary to develop a measurement and diagnosis device that can be connected near the winding measurement end and can measure the winding deformation of transformers that have withstood mechanical and electrodynamic forces. Summary of the Invention

[0004] To solve the deficiencies in the prior art, the present invention provides a wireless distributed transformer winding deformation diagnosis device. To achieve the invention purpose of the present invention, the technical solutions adopted by the present invention are as follows: A wireless distributed transformer winding deformation diagnosis device includes a front-end sensing module, a wireless transmission module, and a host computer. The housing of the front-end sensing module is a shielding housing, and an on-board low-power frequency-sweeping test circuit is arranged inside; a pair of rotary clamps are arranged on the back of the housing, and a rotary handle is arranged on the top of the housing. The rotary handle and the rotary clamp form a ratchet clamping mechanism, and the rotary handle is used to control the axial opening and closing of the rotary clamp.

[0005] Further, the rotating screw is arranged on the rotating clamp. The screw rod of the rotating screw penetrates through the pair of rotating clamps, and the head of the rotating screw is arranged on one side of the rotating clamp. The rotating screw is used to further control the axial opening and closing of the rotating clamp.

[0006] Further, a grounding ring is arranged at the bottom of the front-end sensing module.

[0007] Further, the grounding ring is of a rotating grounding ring structure, and is used to clamp one end of the grounding wire at the port of the grounding ring.

[0008] Further, a receiving antenna for wireless communication is arranged at the bottom of the front-end sensing module and is electrically connected to the wireless communication unit in the front-end sensing module, and is used to wirelessly transmit the data on the sensing module to the upper computer, and realize real-time online monitoring through the software of the upper computer.

[0009] Further, there are a power indicator light and a power switch at the bottom edge of the front-end sensing module.

[0010] Further, the internal board-mounted low-power sweep frequency test circuit of the front-end sensing module is a detection circuit formed by the integrated design of key functional components, and is powered by a 12V battery, and the battery life is not less than 10 hours.

[0011] Further, the internal board-mounted low-power sweep frequency test circuit of the front-end sensing module includes an excitation signal generation part, a response signal acquisition part, and a control and digital processing part, which are implemented by an FPGA chip; the excitation signal is generated by a sweep frequency signal generator, and its output frequency is controlled by the state machine of the FPGA. After the generated excitation signal is filtered and amplified, it is output externally by the drive circuit. At the same time, the analog signal of the sweep frequency signal generator is converted into a digital signal by an analog-to-digital converter and input into the FPGA; the sine response signal of the measured transformer winding is preprocessed by an analog circuit and amplified in gain, and then input into the analog-to-digital converter for sampling, converted into a digital signal, and input into the FPGA for calculation.

[0012] Further, the excitation signal generation part includes an excitation signal output end, which is used to output a sine excitation signal and inject it into the neutral point of the measured transformer.

[0013] Further, the response signal acquisition part includes two synchronous acquisition ends, which are used to respectively acquire the original excitation signal and the response signal of the measured winding.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: Adopt an integrated encapsulation structure, with good shielding performance, convenient use, battery-powered, eliminating power interference. The ratchet clamping mechanism is adopted to eliminate long-distance wiring, improving the detection accuracy and consistency, achieving three-phase synchronous detection. At the same time, it can form an edge computing network composed of one host computer and multiple front-end sensing modules, expanding the detection range and improving the detection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of the embodiments in conjunction with the accompanying drawings, where: Figure 1 It is a schematic diagram of the overall structure of the front-end sensing module of the present invention; Figure 2 It is a front view structural schematic diagram of the front-end sensing module of the present invention; Figure 3 It is a side view structural schematic diagram of the side view of the front-end sensing module of the present invention; Figure 4 It is a structural schematic diagram of the ratchet clamping mechanism of the front-end sensing module of the present invention; Figure 5 It is a diagnostic measurement schematic diagram of a wireless distributed transformer winding deformation diagnosis device; In the figure: 1. Power supply indicator light, 2. Power switch, 3. Grounding ring, 4. Receiving antenna for wireless communication, 5-1. Rotating handle, 5-2. Rotating clip, 5-3. Rotating screw, 6. Outer shell, 7. Charging interface. EMBODIMENTS

[0016] In order to more clearly understand the above objects, features and advantages of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments in the embodiments of the present invention. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0017] Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention may be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below. EXAMPLE

[0018] As Figures 1-4 shown, the front-end sensing module is installed at the bushing electrode of the measured winding to achieve seamless docking of the test ports. The main parameters and other information are displayed on the nameplate of the outer shell 6 of the front-end sensing module. During the test installation process, the wireless ID numbers of each sensing unit need to be recorded and corresponding to them one by one in the acquisition software of the host computer.

[0019] When in use, after pressing the power switch of the sensing unit, the power indicator light will turn on. The power indicator light has three different colors, corresponding to three power states respectively. When the power indicator light is green, the power is sufficient at this time; when the power indicator light is blue, the power is normal and charging can be considered; when the power indicator light is red, the power is insufficient and charging is required immediately. When the power is insufficient, it can be charged using a charger.

[0020] A grounding ring 3 is provided at the bottom end of the housing 6. By rotating the grounding ring 3, one end of the grounding wire is clamped on the grounding ring 3 to achieve a reliable connection nearby. Embodiment

[0021] As Figure 4 As shown, the front-end sensing module is provided with a ratchet clamping mechanism, including a rotating handle 5-1, a rotating clip 5-2 and a rotating screw 5-3. Before use, the two rotating clips 5-2 are in a closed state. By rotating the rotating handle 5-1, the two rotating clips 5-2 are in an open state. Then, the copper sheet on the high-voltage and low-voltage bushings of the transformer is placed between the two rotating clips 5-2, and then the rotating handle 5-1 is rotated to close the two rotating clips 5-2 to clamp the copper sheet. If fine adjustment is needed, the rotating screw 5-3 can be rotated for further adjustment to make the rotating clip 5-2 and the copper sheet closer and more reliable in closing, so as to ensure that the rotating clip 5-2 and the copper sheet will not become loose during the test. Embodiment

[0022] The front-end sensing module transmits the collected data to the host computer through wireless communication. The host computer is installed with software for the diagnostic system to analyze and diagnose the internal structure of the transformer winding to confirm whether the internal structure is intact. Embodiment

[0023] Inside the front-end sensing module is a detection circuit formed by the integrated design of key functional components, powered by a 12V battery, and the battery life is not less than 10 hours. To improve the shielding performance and use convenience of the circuit, a special shielding housing is used to encapsulate the detection circuit main board and the interface module, forming a wireless low-power distributed detection device that can be used for detecting winding deformation by the frequency response method. Embodiment

[0024] As Figure 5As shown, a 380V / 25kVA isolation transformer is used as the test object. When the front-end sensing module, as the lower computer, communicates interactively with the winding under test and the upper computer through a wireless network, a sinusoidal excitation signal Vs is generated under the control of the upper computer. The sinusoidal excitation signal Vs is injected from the neutral point of the transformer under test. The response signal V2 of the winding under test and the original excitation signal V1 respectively enter the synchronous acquisition end of the front-end sensing module for data acquisition. By extracting basic parameters such as the amplitude and frequency of the measured signal, the amplitude-frequency characteristic curve of the winding under test is calculated, so as to obtain the deformation situation of the transformer winding. After the detection device completes the above detection and calculation, the calculated data is uploaded to the upper computer, and the operator conducts in-depth analysis of the uploaded data through the human-computer interaction interface. Embodiment

[0025] The front-end sensing module includes an excitation signal output end and two synchronous acquisition ends. The excitation signal output end outputs a sinusoidal excitation signal and injects it into the neutral point of the transformer under test; the two synchronous acquisition ends respectively collect the original excitation signal and the response signal of the winding under test. The front-end sensing module injects the excitation signal from the tail end of the winding under test under the wireless control of the upper computer, obtains the response signal from the head end of the winding under test, automatically processes the detection data, and uploads the data processing result to the upper computer through the wireless network after the frequency sweep ends. The detection result can be viewed and analyzed through the human-computer interaction interface. Embodiment

[0026] The internal board-mounted low-power frequency-sweeping test circuit of the front-end sensing module includes an excitation signal generation part, a response signal acquisition part, and a control and digital processing part, which are implemented by an FPGA chip; the excitation signal is generated by a frequency-sweeping signal generator, and its output frequency is controlled by the state machine of the FPGA. After the generated excitation signal is filtered and amplified, it is output externally by the drive circuit. The analog signal of the frequency-sweeping signal generator is simultaneously converted into a digital signal by an analog-to-digital converter and input into the FPGA; the sinusoidal response signal of the transformer winding under test is preprocessed by an analog circuit and amplified in gain, and then input into the analog-to-digital converter for sampling, converted into a digital signal, and input into the FPGA for calculation.

[0027] The frequency-sweeping signal generator adopts the direct digital frequency synthesis (DDS) technology, which can quickly and accurately process the frequency and phase under the action of the processor to achieve fast signal transformation. According to the requirements of the frequency response method for detecting winding deformation, the working clock frequency of the DDS sinusoidal signal generator is 50MHz, the output frequency band range is 1kHz~1MHz, and the output frequency resolution is 0.11Hz.

[0028] The board-mounted low-power frequency-sweeping test circuit also includes a wireless communication module, which wirelessly transmits data with the upper computer through a wireless network. It can generate a sinusoidal excitation signal under the control of the upper computer, and the obtained detection result can also be uploaded to the upper computer through the wireless network. Embodiment

[0029] The wireless communication module uses the nRF401 chip for wireless data transmission. The highest working rate of this chip can reach 20k, and the maximum transmitting power is 10dBm. Embodiment

[0030] During detection, the front-end sensing module is seamlessly docked with the transformer winding under test, and the signal transmission distance is no more than 20 cm. Embodiment

[0031] A wireless distributed transformer winding deformation diagnosis device includes a front-end sensing module, a wireless transmission module, and a host computer. The housing 6 of the front-end sensing module is a shielding housing, and an on-board low-power sweep test circuit is arranged inside; Rotating clamps 5-2 are arranged in pairs on the back of the housing 6, and a rotating handle 5-1 is arranged on the housing 6. The rotating handle 5-1 and the rotating clamp 5-2 form a ratchet clamping mechanism, and the rotating handle 5-1 is used to control the axial opening and closing of the rotating clamp 5-2. Embodiment

[0032] The rotating screw 5-3 is arranged on the rotating clamp 5-2. The screw rod of the rotating screw 5-3 penetrates through the paired rotating clamps 5-2, and the head of the rotating screw 5-3 is arranged on one side of the rotating clamp 5-2. Embodiment

[0033] A grounding ring 3 is arranged at the bottom of the front-end sensing module; The grounding ring 3 is a rotating grounding ring structure, which is used to clamp one end of the grounding wire at the port of the grounding ring 3. Embodiment

[0034] A receiving antenna 4 for wireless communication is arranged at the bottom of the front-end sensing module and is electrically connected to the wireless communication unit in the front-end sensing module, which is used for wireless communication with the host computer. Embodiment

[0035] A power indicator light 1 and a power switch are arranged at the bottom edge of the front-end sensing module. Embodiment

[0036] The on-board low-power sweep test circuit inside the front-end sensing module is a detection circuit formed by the integrated design of key functional components and is powered by a battery. Embodiment

[0037] The on-board low-power sweep test circuit inside the front-end sensing module includes an excitation signal generation part, a response signal acquisition part, and a control and digital processing part, which are implemented by an FPGA chip. Embodiment

[0038] The excitation signal generation part includes an excitation signal output terminal, which is used to output a sine excitation signal and inject it into the neutral point of the transformer under test. Embodiment

[0039] The response signal acquisition part includes two synchronous acquisition terminals for respectively acquiring the original excitation signal and the response signal of the winding under test. Embodiment

[0040] Heat dissipation holes are provided on both sides of the housing 6 of the front-end sensing module.

[0041] In the present invention, terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present invention is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention. In addition, terms such as "horizontal", "vertical", "hanging", etc. do not mean that the component must be absolutely horizontal or hanging, but can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined.

[0042] In the present invention, unless otherwise clearly defined and limited, terms such as "installation", "connection", "connection", "fixation", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] In the description of the present invention, it should be understood that the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0044] The applicant of the present invention has made a detailed description and illustration of the embodiments of the present invention in combination with the accompanying drawings of the specification. However, those skilled in the art should understand that the above embodiments are only the preferred implementation schemes of the present invention, and the detailed description is only to help readers better understand the spirit of the present invention, rather than a limitation on the protection scope of the present invention. On the contrary, any improvement or modification based on the spirit of the present invention should fall within the protection scope of the present invention.

Claims

1. A wireless distributed transformer winding deformation diagnosis device, comprising a front-end sensing module, a wireless transmission module and a host computer, characterized in that: The housing (6) of the front-end sensing module is a shielded housing, and an on-board low-power sweep test circuit is arranged inside; a pair of rotary clamps (5-2) are arranged on the back of the housing (6), a rotary handle (5-1) is arranged on the housing (6), and the rotary handle (5-1) and the rotary clamp (5-2) form a ratchet clamping mechanism, and the rotary handle (5-1) is used to control the axial opening and closing of the rotary clamp (5-2).

2. The wireless distributed transformer winding deformation diagnosis device according to claim 1, characterized in that: The rotary screw (5-3) is arranged on the rotary clamp (5-2), the screw rod of the rotary screw (5-3) penetrates through the pair of rotary clamps (5-2) arranged in pairs, and the head of the rotary screw (5-3) is arranged on one side of the rotary clamp (5-2).

3. A wireless distributed transformer winding deformation diagnosis device according to claim 1, characterized in that: A grounding ring (3) is arranged at the bottom of the front-end sensing module.

4. The wireless distributed transformer winding deformation diagnosis device according to claim 2, characterized in that: The grounding ring (3) is a rotary grounding ring structure, and is used to clamp one end of the grounding wire at the port of the grounding ring (3).

5. A wireless distributed transformer winding deformation diagnosis device according to claim 1, characterized in that: A receiving antenna (4) for wireless communication is arranged at the bottom of the front-end sensing module and is electrically connected to the wireless communication unit in the front-end sensing module, and is used for wireless communication with the upper computer.

6. The wireless distributed transformer winding deformation diagnosis device according to claim 1, characterized in that: A power indicator light (1) and a power switch (2) are arranged at the bottom edge of the front-end sensing module.

7. The wireless distributed transformer winding deformation diagnosis device according to claim 1, characterized in that: The on-board low-power sweep test circuit inside the front-end sensing module is a detection circuit formed by the integrated design of key functional components and is powered by a battery.

8. The wireless distributed transformer winding deformation diagnosis device according to claim 7, characterized in that: The on-board low-power sweep test circuit inside the front-end sensing module includes an excitation signal generation part, a response signal acquisition part, and a control and digital processing part, and is implemented by an FPGA chip.

9. The wireless distributed transformer winding deformation diagnosis device according to claim 8, wherein: The excitation signal generation part includes an excitation signal output end, which is used to output a sine excitation signal and inject it into the neutral point of the transformer under test.

10. The wireless distributed transformer winding deformation diagnosis device according to claim 7, characterized in that: The response signal acquisition part includes two synchronous acquisition ends, which are used to respectively acquire the original excitation signal and the response signal of the winding under test.

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