Generator partial discharge on-line monitoring system

Abstract

The utility model discloses a generator partial discharge on-line monitoring system, which belongs to the field of generator partial discharge monitoring and comprises a microstrip patch Hilbert fractal antenna, a high-pass filter, a signal amplifier and a signal processing unit. The microstrip patch Hilbert fractal antenna is connected with the high-pass filter and is used for acquiring a partial discharge ultrahigh frequency signal and transmitting the partial discharge ultrahigh frequency signal to the high-pass filter; the high-pass filter is connected with the signal amplifier and is used for filtering the partial discharge ultrahigh frequency signal and then transmitting the partial discharge ultrahigh frequency signal to the signal amplifier; the signal amplifier is connected with the signal processing unit and is used for amplifying the filtered partial discharge ultrahigh frequency signal and transmitting the amplified partial discharge ultrahigh frequency signal to the signal processing unit; and the signal processing unit is used for recording and analyzing the amplified partial discharge ultrahigh frequency signal to obtain a partial discharge result and storing the partial discharge result. According to the utility model, ultrahigh frequency signals of partial discharge can be monitored, and the monitoring accuracy is improved.

Description

Technical Field

[0001] This utility model belongs to the field of generator partial discharge monitoring, specifically relating to an online monitoring system for generator partial discharge. Background Technology

[0002] The electrical insulation level of a generator is one of the main factors affecting its safe operation, and partial discharge is closely related to its insulation degradation and breakdown. Partial discharge can both reflect the generator's insulation level and accelerate its degradation. Online monitoring of partial discharge in generators can effectively assess the stator winding insulation condition and improve generator operational safety.

[0003] Partial discharge has a wide frequency distribution, and can be monitored in low-frequency (<3MHz), high-frequency (3~30MHz), high-frequency (30~300MHz), and ultra-high-frequency (300~3000MHz) bands. Currently, generator partial discharge monitoring mainly focuses on the low-frequency to high-frequency range, but external pulse interference also falls within this band, which can affect the monitoring results. Therefore, it is necessary to acquire ultra-high-frequency signals of partial discharge to improve the reliability of online monitoring results. Utility Model Content

[0004] The purpose of this invention is to provide an online monitoring system for partial discharge of generators, which can monitor ultra-high frequency signals of partial discharge and improve monitoring accuracy.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] In a first aspect, a generator partial discharge online monitoring system includes: a microstrip patch Hilbert fractal antenna, a high-pass filter, a signal amplifier, and a signal processing unit;

[0007] A microstrip patch Hilbert fractal antenna is connected to a high-pass filter to acquire and transmit partial discharge UHF signals to the high-pass filter.

[0008] A high-pass filter is connected to a signal amplifier to filter the partial discharge ultra-high frequency signal before transmitting it to the signal amplifier;

[0009] The signal amplifier is connected to the signal processing unit and is used to amplify the filtered partial discharge ultra-high frequency signal and transmit it to the signal processing unit.

[0010] The signal processing unit is used to record and analyze the amplified partial discharge ultra-high frequency signal to obtain the partial discharge result and save it.

[0011] In some embodiments, a monitoring and display module is also included, which is connected to the signal processing unit via a data cable to receive and display the partial discharge results.

[0012] In some implementations, the high-pass filter includes terminating impedance Z1, terminating impedance Z2, capacitor C1, capacitor C2, capacitor C3, inductor L1, and inductor L2.

[0013] The terminating impedance Z1 is connected to capacitor C1. Capacitor C1 is connected in parallel with capacitor C2 and inductor L1. Capacitor C2 is connected in parallel with capacitor C3 and inductor L2. Inductor L2 is connected to the terminating impedance Z2. Terminating impedance Z1, terminating impedance Z2, inductor L1 and inductor L2 are grounded.

[0014] In some implementations, both the terminating impedance Z1 and the terminating impedance Z2 are 50Ω.

[0015] In some implementations, capacitors C1 and C3 have the same capacitance value, and inductors L1 and L2 have the same inductance value.

[0016] In some implementations, the amplification gain of the signal amplifier is greater than or equal to 20 dB.

[0017] In some implementations, the frequency amplification range of the signal amplifier is 20MHz to 6GHz.

[0018] In some implementations, the high-pass filter has a bandwidth of 300MHz to 1000MHz.

[0019] In some implementations, the signal processing unit employs a central processing unit.

[0020] In some implementations, the monitoring and display module includes an embedded processor and a display, wherein the embedded processor receives the partial discharge results, draws them, and then displays them on the display.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] This invention provides an online monitoring system for partial discharge in generators, comprising: a microstrip patch Hilbert fractal antenna, a high-pass filter, a signal amplifier, and a signal processing unit. The microstrip patch Hilbert fractal antenna is connected to the high-pass filter to acquire and transmit ultra-high frequency (UHF) signals of partial discharge. The high-pass filter is connected to the signal amplifier to filter the UHF signals before transmitting them to the signal amplifier. The signal amplifier is connected to the signal processing unit to amplify the filtered UHF signals and transmit them to the signal processing unit. The signal processing unit records and analyzes the amplified UHF signals to obtain and save the partial discharge results. This invention, by employing a microstrip patch Hilbert fractal antenna, can efficiently and accurately acquire UHF signals generated locally by the generator, which is beneficial for capturing weak and high-frequency discharge signals, improving monitoring sensitivity. Combined with the high-pass filter and signal amplifier, it can automatically filter out external interference, improving monitoring accuracy.

[0023] Furthermore, the high-pass filter of this invention includes a terminating impedance Z1, a terminating impedance Z2, capacitors C1, C2, and C3, and inductors L1 and L2. The terminating impedance Z1 is connected to capacitor C1, capacitor C1 is connected in parallel with capacitor C2 and inductor L1, capacitor C2 is connected in parallel with capacitor C3 and inductor L2, and inductor L2 is connected to the terminating impedance Z2. The terminating impedances Z1 and Z2, inductors L1 and L2 are grounded. This high-pass filter can effectively filter out lower frequency components in the partial discharge ultra-high frequency signal, reduce background noise interference, and improve signal quality.

[0024] Furthermore, the signal amplifier of this invention has an amplification gain greater than or equal to 20dB and a frequency amplification range of 20MHz~6GHz, which can match the output of the high-pass filter and ensure that the partial discharge ultra-high frequency signal is not distorted during amplification, thereby enhancing the analyzability of the partial discharge ultra-high frequency signal.

[0025] Furthermore, the high-pass filter of this invention has a frequency band of 300MHz~1000MHz, which is the main frequency band of the partial discharge ultra-high frequency signal, and is beneficial for capturing key information. Attached Figure Description

[0026] Figure 1 This is a curve fill diagram of the Hilbert fractal antenna used in Example 1;

[0027] Figure 2 This is a schematic diagram of the high-pass filter used in Example 1;

[0028] Figure 3 This is a schematic diagram of the structure of an online monitoring system for partial discharge of a generator provided in Embodiment 1;

[0029] In the figure, 1. Microstrip patch Hilbert fractal antenna; 2. High-pass filter; 3. Signal amplifier; 4. Signal processing unit; 5. Monitoring and display module. Detailed Implementation

[0030] In the following description, only certain exemplary embodiments are briefly described. The described embodiments can be modified in various ways without departing from the spirit or scope of this invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0031] 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 utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0032] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0033] The accompanying drawings show structural schematic diagrams according to embodiments of the present invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0034] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0035] Example 1

[0036] like Figure 3 As shown, this embodiment provides an online monitoring system for partial discharge of a generator. It uses a Hilbert fractal antenna to monitor partial discharge of the generator. The system can use ultra-high frequency partial discharge monitoring to automatically filter out external interference and improve the accuracy of monitoring. The system includes: a signal acquisition module, a signal filtering module, a signal amplification module, a signal processing module, and a monitoring display module.

[0037] The signal acquisition module uses a microstrip patch Hilbert fractal antenna 1 to acquire the partial discharge ultra-high frequency signal of the generator and transmit it to the signal filtering module.

[0038] The signal filtering module filters out low-frequency signals or interference signals in the partial discharge ultra-high frequency signal through high-pass filter 2 before transmitting it to the signal amplification module. The frequency band of high-pass filter 2 is 300MHz~1000MHz.

[0039] The signal amplification module uses signal amplifier 3 to amplify the obtained partial discharge ultra-high frequency signal and then transmit it to signal processing unit 4;

[0040] Specifically, after amplifying weak ultra-high frequency signals, the signal amplifier has an amplification gain of not less than 20dB and can amplify frequencies ranging from 20MHz to 6GHz.

[0041] The signal processing unit analyzes and records the obtained partial discharge ultra-high frequency signals.

[0042] The monitoring and display module displays and stores the partial discharge ultra-high frequency signal in the signal processing unit 4.

[0043] Specifically, the microstrip patch Hilbert fractal antenna 1 is mounted on the surface of the generator stator bar. The curves in the Hilbert fractal antenna are continuous curves without any intersections. Each higher-order Hilbert fractal curve is composed of copies, arrangements, and connections of the previous-order curve. These curves gradually fill the space at a higher rate using new curve structures with self-similarity, such as... Figure 1 As shown.

[0044] Hilbert fractal curve outer dimensions L The length of each line segment is d , n Total length of fractal curve s Calculate using formulas (1) and (2):

[0045] (1)

[0046] (2)

[0047] Given a fixed width for the Hilbert antenna material, it is possible to determine based on different... n , L To determine the resonant frequency of the fractal antenna.

[0048] Specifically, the ultra-high frequency signal acquired by the microstrip patch Hilbert fractal antenna 1 is transmitted to a high-pass filter 2 to eliminate relatively low-frequency signals. The structure of the high-pass filter 2 is as follows: Figure 2As shown, the system includes terminating impedance Z1, terminating impedance Z2, capacitor C1, capacitor C2, capacitor C3, inductor L1, and inductor L2. Terminating impedance Z1 is connected to capacitor C1, capacitor C1 is connected in parallel with capacitor C2 and inductor L1, capacitor C2 is connected in parallel with capacitor C3 and inductor L2, inductor L2 is connected to terminating impedance Z2, and terminating impedance Z1, terminating impedance Z2, inductor L1, and inductor L2 are grounded.

[0049] The terminating impedances Z1 and Z2 are both 50Ω, the capacitances of capacitors C1 and C3 are equal, and the inductances of inductors L1 and L2 are equal. The capacitances of capacitors C1, C2, C3, L1, and L2 can be adjusted according to the required cutoff frequency.

[0050] The specific working process of the generator partial discharge online monitoring system provided in this embodiment is as follows:

[0051] A microstrip patch Hilbert fractal antenna 1 is mounted on the surface of the generator stator bar (pre-installed with the manufacturer) to acquire the generator's partial discharge UHF signal and transmit it to a high-pass filter 2. The high-pass filter 2 filters out the lower frequency signals in the signal and transmits the filtered partial discharge UHF signal to a signal amplifier 3 for amplification. The amplified signal is then sent to a signal processing unit 4 for analysis and recording. The analyzed data results are transmitted to a monitoring and display module 5 via a data cable for plotting, displaying, and storing the partial discharge results for learning and comparison.

[0052] This embodiment provides a system for monitoring partial discharge in a generator using a Hilbert fractal antenna. A microstrip patch Hilbert fractal antenna is mounted on the surface of the generator stator bars (pre-installed in conjunction with the manufacturer) to obtain ultra-high frequency (UHF) signals of partial discharge. After filtering, amplification, and analysis, the partial discharge signals are displayed on a monitoring module, and the partial discharge signal data is stored. This system acquires UHF signals of partial discharge and features strong anti-interference capabilities, high sensitivity, and high resolution.

[0053] Example 2

[0054] This embodiment provides an online monitoring system for partial discharge of a generator, including a microstrip patch Hilbert fractal antenna 1, a high-pass filter 2, a signal amplifier 3, and a signal processing unit 4;

[0055] The microstrip patch Hilbert fractal antenna 1 is connected to the high-pass filter 2 to collect and transmit the partial discharge ultra-high frequency signal to the high-pass filter 2.

[0056] The high-pass filter 2 is connected to the signal amplifier 3 and is used to filter the partial discharge ultra-high frequency signal before transmitting it to the signal amplifier 3;

[0057] The signal amplifier 3 is connected to the signal processing unit 4 and is used to amplify the filtered partial discharge ultra-high frequency signal and transmit it to the signal processing unit 4.

[0058] The signal processing unit 4 is used to record and analyze the amplified partial discharge ultra-high frequency signal to obtain the partial discharge result and save it.

[0059] The monitoring and display module 5 is connected to the signal processing unit 4 via a data cable, and is used to receive and display the partial discharge results.

[0060] The high-pass filter 2 includes terminating impedance Z1, terminating impedance Z2, capacitors C1, C2, and C3, and inductors L1 and L2. Terminating impedance Z1 is connected to capacitor C1, capacitor C1 is connected in parallel with capacitor C2 and inductor L1, capacitor C2 is connected in parallel with capacitor C3 and inductor L2, and inductor L2 is connected to terminating impedance Z2. Terminating impedance Z1, terminating impedance Z2, inductor L1, and inductor L2 are grounded. Terminating impedance Z1 and terminating impedance Z2 are both 50Ω, capacitors C1 and C3 have the same capacitance value, and inductors L1 and L2 have the same inductance value.

[0061] The amplification gain of signal amplifier 3 is greater than or equal to 20dB, and the frequency amplification range of signal amplifier 3 is 20MHz~6GHz.

[0062] The high-pass filter 2 has a bandwidth of 300MHz to 1000MHz. The signal processing unit 4 uses a central processing unit. The monitoring and display module 5 includes an embedded processor and a display. The embedded processor receives the partial discharge results, plots them, and then displays them on the display.

[0063] The generator partial discharge online monitoring system provided in this embodiment can efficiently and accurately acquire ultra-high frequency signals generated locally by the generator by using a microstrip patch Hilbert fractal antenna. This is beneficial for capturing weak and high-frequency discharge signals, improving monitoring sensitivity. In addition, combined with a high-pass filter and signal amplifier, it can automatically filter out external interference and improve monitoring accuracy.

[0064] As is known from common technical knowledge, this utility model can be implemented through other embodiments that do not depart from its spirit or essential characteristics. Therefore, the above-disclosed embodiments are merely illustrative in all respects and are not the only ones. All changes within the scope of this utility model or equivalent to this utility model are included in this utility model.

Claims

1. A generator partial discharge online monitoring system, characterized in that, include: Microstrip patch Hilbert fractal antenna (1), high-pass filter (2), signal amplifier (3), signal processing unit (4); A microstrip patch Hilbert fractal antenna (1) is connected to a high-pass filter (2) to collect partial discharge ultra-high frequency signals and transmit them to the high-pass filter (2). The high-pass filter (2) is connected to the signal amplifier (3) to filter the partial discharge ultra-high frequency signal and then transmit it to the signal amplifier (3). The signal amplifier (3) is connected to the signal processing unit (4) to amplify the filtered partial discharge ultra-high frequency signal and transmit it to the signal processing unit (4). The signal processing unit (4) is used to record and analyze the amplified partial discharge ultra-high frequency signal to obtain the partial discharge result and save it. The high-pass filter (2) includes a terminal impedance Z1, a terminal impedance Z2, a capacitor C1, a capacitor C2, a capacitor C3, an inductor L1, and an inductor L2; The terminal impedance Z1 is connected to capacitor C1, capacitor C1 is connected in parallel with capacitor C2 and inductor L1, capacitor C2 is connected in parallel with capacitor C3 and inductor L2, inductor L2 is connected to terminal impedance Z2, and terminal impedance Z1, terminal impedance Z2, inductor L1 and inductor L2 are grounded; the amplification gain of signal amplifier (3) is greater than or equal to 20dB; the frequency amplification range of signal amplifier (3) is 20MHz~6GHz.

2. The generator partial discharge online monitoring system according to claim 1, characterized in that, It also includes a monitoring and display module (5), which is connected to the signal processing unit (4) via a data line to receive and display the partial discharge results.

3. The generator partial discharge online monitoring system according to claim 1, characterized in that, Both the terminating impedance Z1 and the terminating impedance Z2 are 50Ω.

4. The generator partial discharge online monitoring system according to claim 1, characterized in that, Capacitors C1 and C3 have the same capacitance value, and inductors L1 and L2 have the same inductance value.

5. The generator partial discharge online monitoring system according to claim 1, characterized in that, The bandwidth of the high-pass filter (2) is 300MHz~1000MHz.

6. The generator partial discharge online monitoring system according to claim 1, characterized in that, The signal processing unit (4) uses a central processing unit.

7. The generator partial discharge online monitoring system according to claim 1, characterized in that, The monitoring and display module (5) includes an embedded processor and a display. The embedded processor receives the partial discharge results, draws them, and then displays them on the display.

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