Method for multi-channel detection of ultrasonic partial discharge signals

Abstract

An ultrasonic partial discharge signal multi-channel detection method is disclosed. In the method, a first ultrasonic sensor collects a first ultrasonic signal and converts it into a first electrical signal, a first signal amplifier amplifies the first electrical signal, and a signal delay device receives the first electrical signal and delays it; a second ultrasonic sensor collects a second ultrasonic signal and converts it into a second electrical signal, and a second signal amplifier amplifies the second electrical signal; a signal convergence point is respectively connected to the signal delay device and is connected to the second signal amplifier via a wire to collect the first electrical signal and the second electrical signal with a timing difference.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrical equipment detection, and particularly relates to a method for multi-channel detection of ultrasonic partial discharge signals. Background Art

[0002] Ultrasonic partial discharge detection is widely used in equipment such as transformers and gas-insulated switchgears, and has the characteristics of convenient use and strong anti-interference ability. When using ultrasonic partial discharge detection, it is often necessary to collect signals from multiple sensors simultaneously. At this time, multiple collector devices are required to collect each path of signals separately, which results in a large volume, high cost, and difficulty in ensuring synchronization of the collection device.

[0003] The above information disclosed in the background art section is only used to enhance the understanding of the background of the present invention, and therefore may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for multi-channel detection of ultrasonic partial discharge signals, which uses a time delay device to converge multiple signals into a signal with different time sequences and send it to the collection device, realizing the collection of multiple signals by one collection device, reducing the cost, and improving the synchronization.

[0005] In order to achieve the above purpose, the present invention provides the following technical solutions:

[0006] A method for multi-channel detection of ultrasonic partial discharge signals of the present invention includes:

[0007] The first ultrasonic sensor collects the first ultrasonic signal and converts it into the first electrical signal, the first signal amplifier amplifies the first electrical signal, and the signal delay device receives the first electrical signal and delays it;

[0008] The second ultrasonic sensor collects the second ultrasonic signal and converts it into the second electrical signal, and the second signal amplifier amplifies the second electrical signal;

[0009] The signal convergence point is respectively connected to the signal delay device and connected to the second signal amplifier via a wire to collect the first electrical signal and the second electrical signal with different time sequences.

[0010] In the method for multi-channel detection of ultrasonic partial discharge signals, the signal delay device includes a metal shell with openings at both ends and an insulating seal for sealing the metal shell at the openings. The signal delay device is filled with a filler, and a conductor is introduced and passes through the signal delay device.

[0011] In the method for multi-channel detection of ultrasonic partial discharge signals, the filler is formed by doping permalloy powder into epoxy resin and curing.

[0012] In the described multi-channel detection method for ultrasonic partial discharge signals, the relative magnetic permeability of the permalloy powder is 100,000, the relative dielectric constant of the epoxy resin is 5, and the wave velocity of the first electrical signal after passing through the signal delay device is where v is the speed of light, μ r is the relative magnetic permeability of the filler, which is determined by the relative magnetic permeability of the permalloy powder; ε r is the relative dielectric constant of the filler, which is determined by the relative dielectric constant of the epoxy resin.

[0013] In the described multi-channel detection method for ultrasonic partial discharge signals, the wave velocity of the first electrical signal in the signal delay device is 1 / 707 of the speed of light.

[0014] In the described multi-channel detection method for ultrasonic partial discharge signals, the amplification factor of the second signal amplifier is the same as that of the first signal amplifier.

[0015] In the described multi-channel detection method for ultrasonic partial discharge signals, the multi-channel detection method simultaneously measures multiple ultrasonic signals to form electrical signals with time sequence differences.

[0016] In the described multi-channel detection method for ultrasonic partial discharge signals, both the first ultrasonic sensor and the second ultrasonic sensor are piezoelectric ultrasonic sensors.

[0017] In the described multi-channel detection method for ultrasonic partial discharge signals, the measuring device of the first ultrasonic sensor or the second ultrasonic sensor is a gas-insulated fully enclosed combined electrical apparatus.

[0018] In the above technical solution, the multi-channel detection method for ultrasonic partial discharge signals provided by the present invention has the following beneficial effects: The present invention uses a time delay device to converge multiple signals into a signal with time sequence differences and sends it to the acquisition device, achieving the purpose of simultaneously collecting at least two ultrasonic detection signals with one set of acquisition system, and can realize the low-cost and high-synchronization acquisition of ultrasonic detection signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0020] Figure 1 It is a layout schematic diagram of the multi-channel detection method for ultrasonic partial discharge signals in the present invention;

[0021] Figure 2Schematic diagram of the signal delay device for the multi-channel detection method of ultrasonic partial discharge signals in the present invention;

[0022] Figure 3 Schematic diagram of signal aggregation for the multi-channel detection method of ultrasonic partial discharge signals in the present invention. Specific embodiments

[0023] To make the purpose, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0024] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0025] It should be noted that similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. 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 of the present invention.

[0027] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more, unless otherwise specifically defined.

[0028] In the present invention, unless otherwise clearly specified or limited, the terms "mounted", "connected", "coupled", "fixed", etc. shall be construed in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral body; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two components or the interaction relationship between two components. 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.

[0029] In the present invention, unless otherwise clearly specified or limited, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely means that the horizontal height of the first feature is lower than that of the second feature.

[0030] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0031] As Figures 1 to 3 shown, in one embodiment, the multi-channel detection method for ultrasonic partial discharge signals includes,

[0032] The first ultrasonic sensor 1 collects the first ultrasonic signal and converts it into a first electrical signal. The first signal amplifier 3 amplifies the first electrical signal. The signal delay device 5 receives the first electrical signal and delays it;

[0033] The second ultrasonic sensor 2 collects the second ultrasonic signal and converts it into a second electrical signal. The second signal amplifier 4 amplifies the second electrical signal,

[0034] The signal convergence point 7 is respectively connected to the signal delay device 5 and is connected to the second signal amplifier 4 via the wire 6 to collect the first electrical signal and the second electrical signal with a time sequence difference.

[0035] In a preferred embodiment of the multi-channel detection method for ultrasonic partial discharge signals, the signal delay device 5 includes a metal shell 8 with openings at both ends and an insulating seal 9 provided at the openings to seal the metal shell 8. The signal delay device 5 is internally provided with a filler 11, and a conductor 10 is introduced and passes through the signal delay device 5.

[0036] In a preferred embodiment of the multi-channel detection method for ultrasonic partial discharge signals, the filler 11 is formed by doping permalloy powder into epoxy resin and curing.

[0037] In a preferred embodiment of the described multi-channel detection method for ultrasonic partial discharge signals, the relative magnetic permeability of the permalloy powder is 100,000, the relative dielectric constant of the epoxy resin is 5, and the wave velocity of the first electrical signal after passing through the signal delay device 5 is where v is the speed of light, μ r is the relative magnetic permeability of the filler 11, which is determined by the relative magnetic permeability of the permalloy powder; ε r is the relative dielectric constant of the filler 11, which is determined by the relative dielectric constant of the epoxy resin.

[0038] In a preferred embodiment of the described multi-channel detection method for ultrasonic partial discharge signals, the wave velocity of the first electrical signal in the signal delay device 5 is 1 / 707 of the speed of light.

[0039] In a preferred embodiment of the described multi-channel detection method for ultrasonic partial discharge signals, the amplification factor of the second signal amplifier 4 is the same as that of the first signal amplifier 3.

[0040] In a preferred embodiment of the described multi-channel detection method for ultrasonic partial discharge signals, the multi-channel detection method simultaneously measures multiple ultrasonic signals to form electrical signals with time-sequence differences.

[0041] In a preferred embodiment of the described multi-channel detection method for ultrasonic partial discharge signals, both the first ultrasonic sensor 1 and the second ultrasonic sensor 2 are piezoelectric ultrasonic sensors.

[0042] In a preferred embodiment of the described multi-channel detection method for ultrasonic partial discharge signals, the measuring device of the first ultrasonic sensor 1 or the second ultrasonic sensor 2 is a gas-insulated fully enclosed combined electrical apparatus.

[0043] In one embodiment, the signal convergence point 7 is connected to a filter to filter the electrical signals with time-sequence differences.

[0044] In one embodiment, the conductor 10 sequentially passes through the insulating seal at one end, the filler, and the insulating seal at the other end.

[0045] In one embodiment, the method includes a first ultrasonic sensor 1 and a second ultrasonic sensor 2, a first signal amplifier 3 and a second signal amplifier 4, a signal delay device 5 connected in series with the first signal amplifier 3, a wire 6 and a signal convergence point 7 connected in series with the second signal amplifier 4. Two ultrasonic signals form a signal with a difference in time sequence at the signal convergence point 7 and are sent to the acquisition system. The purpose of simultaneously collecting two ultrasonic detection signals by one set of acquisition system is achieved, and low-cost and high-synchronization acquisition of ultrasonic detection signals can be realized. The multiple ultrasonic detection signals are amplified and then sent to delay devices with different delay times, and are converged into one signal and sent to the acquisition device, so as to realize the acquisition of multiple signals by one acquisition device, thereby achieving the purpose of reducing costs and improving synchronization.

[0046] In one embodiment, the first ultrasonic sensor 1 and the second ultrasonic sensor 2 are piezoelectric ultrasonic sensors. The detected ultrasonic signals are converted into electrical signals and amplified by the first amplifier 3 and the second amplifier 4. The amplification factor of the amplifier can be arbitrarily selected. The first electrical signal amplified by the first amplifier 3 is sent to the signal delay device 5. The specific structure of the signal delay device is as Figure 2 shown. Among them, the metal shell 8 is of a cylindrical structure, the insulating seal 9 seals the metal shell 8, the conductor 10 is introduced and passes through the signal delay device, and the inside of the delay device is filled with a filler 11, where the filler is formed by curing permalloy powder doped with epoxy resin. The relative magnetic permeability of the permalloy powder is 100,000, and the relative dielectric constant of the epoxy resin is 5. Then the wave velocity of the signal after passing through the delay device is where v is the speed of light, μ r is the relative magnetic permeability of the filler, which is determined by the relative magnetic permeability of the permalloy powder; ε r is the relative dielectric constant of the filler, which is determined by the relative dielectric constant of the epoxy resin. Then the wave velocity of the signal in the delay device is v1 = v / 707, that is, its speed is 1 / 707 of the speed of light. The other signal is directly sent to the convergence point through the wire 6 after being amplified by the second signal amplifier 4. The propagation speed of the signal in the wire is the speed of light. Then the two signals form one signal after converging at the convergence point 7. The signal contains signals with a time sequence difference from the first ultrasonic sensor 1 and the second ultrasonic sensor 2. The schematic diagram is as Figure 3As shown. The magnitude of the time difference between the two signals is determined by the length of the delay device, which can be arbitrarily selected according to the situation. Through the above operations, multiple signals can pass through signal delay devices with different lengths respectively and finally be aggregated into one signal. This signal contains multiple ultrasonic partial discharge signals with different time delays, and sampling can be achieved through a sampling device, which reduces the cost and at the same time avoids the synchronization error caused by the differences of multiple sampling devices themselves, improving the synchronization accuracy. In practical applications, various parameters can be flexibly adjusted. For example, the number of signal channels can be collected according to needs, the amplification factor of the amplifier can be designed according to needs, and the magnitude of the time delay can be designed according to actual needs, etc.

[0047] Finally, it should be noted that the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0048] Only some exemplary embodiments of the present invention have been described by way of illustration above. Without doubt, for those of ordinary skill in the art, the described embodiments can be modified in various different ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A method for multiplex detection of ultrasonic partial discharge signals, characterized in that It includes the following steps: The first ultrasonic sensor collects the first ultrasonic signal and converts it into a first electrical signal. The first signal amplifier amplifies the first electrical signal. The signal delay device receives the first electrical signal and delays it. The second ultrasonic sensor collects the second ultrasonic signal and converts it into a second electrical signal. The second signal amplifier amplifies the second electrical signal. Among them, there is a timing difference between the first electrical signal and the second electrical signal. The signal delay device and the second signal amplifier connected via a wire are respectively connected through a signal convergence point to collect the first electrical signal and the second electrical signal with a timing difference. The signal delay device includes a metal shell with openings at both ends and an insulating seal provided at the openings to seal the metal shell. The signal delay device is filled with a filler. A conductor is introduced and passes through the signal delay device. The magnitude of the time difference between the two signals is determined by the length of the delay device. The signal convergence point is connected to a filter to filter the electrical signals with a timing difference. Among them, The method uses the signal delay device to converge multiple signals into a signal with a timing difference and sends it to the acquisition device, realizing the acquisition of multiple signals by one acquisition device. The filler is formed by doping Permalloy powder into epoxy resin and curing. The relative magnetic permeability of the Permalloy powder is 100,000, and the relative dielectric constant of the epoxy resin is 5. The wave velocity of the first electrical signal after passing through the signal delay device is , where v is the speed of light, μ r is the relative magnetic permeability of the filler, which is determined by the relative magnetic permeability of the Permalloy powder; ε r is the relative dielectric constant of the filler, which is determined by the relative dielectric constant of the epoxy resin; The wave velocity of the first electrical signal in the signal delay device is 1 / 707 of the speed of light.

2. The multiplex detection method for ultrasonic partial discharge signals according to claim 1, wherein The amplification factor of the second signal amplifier is the same as that of the first signal amplifier.

3. A method for multiplex detection of ultrasonic partial discharge signals according to claim 1, characterized in that The multi-channel detection method simultaneously measures multiple ultrasonic signals to form electrical signals with a timing difference.

4. A method for multiplex detection of ultrasonic partial discharge signals according to claim 1, characterized in that Both the first ultrasonic sensor and the second ultrasonic sensor are piezoelectric ultrasonic sensors.

5. A method for multiplex detection of ultrasonic partial discharge signals according to claim 1, characterized in that, The measuring device of the first ultrasonic sensor or the second ultrasonic sensor is a gas-insulated fully enclosed combined electrical appliance.

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