發(fā)布時間：2018-10-04 21:35

【摘要】：目前,隨著氣體絕緣組合開關(guān)(GIS)在高壓系統(tǒng)中應(yīng)用得越來越廣泛,人們對GIS局部放電檢測的研究也越來越多。本文通過對超高頻(UHF)局部放電檢測法進(jìn)行研究,總結(jié)了該檢測法所存在的問題。由于局部放電發(fā)生時產(chǎn)生的脈沖信號強(qiáng)度較弱,空間電磁環(huán)境對放電信號檢測產(chǎn)生的干擾比較大,因此,應(yīng)用ADS仿真軟件設(shè)計了帶通、高通和帶阻濾波器,濾除不同頻段的干擾信號。通過對空間電磁環(huán)境以及局部放電信號的特性進(jìn)行研究,給出了低噪聲放大器和檢波器的最佳工作頻率�；诶碚摲治鲈谧罴压ぷ黝l率處設(shè)計低噪聲放大器和檢波器的匹配電路,使UHF局部放電傳感器在該頻率處于最佳工作狀態(tài)。最后對所設(shè)計的射頻電路進(jìn)行測試,測試結(jié)果表明前端射頻電路能有效濾除空間干擾信號,提高UHF局部放電傳感器的信噪比。論文主要內(nèi)容如下:(1)介紹了GIS設(shè)備的應(yīng)用背景和局部放電形成的機(jī)理以及引起局部放電的主要原因,重點闡述了超高頻局部放電檢測法的現(xiàn)狀以及其優(yōu)缺點。(2)對射頻電路設(shè)計的理論知識進(jìn)行簡要介紹。對濾波器與匹配電路設(shè)計的基本原理進(jìn)行分析,為實際濾波器和匹配電路設(shè)計奠定理論基礎(chǔ)。(3)介紹了超高頻局部放電傳感器前端射頻電路的組成以及功能。由于空間電磁信號對局部放電檢測造成的干擾較大,因此,應(yīng)用ADS仿真軟件設(shè)計帶通、高通和帶阻濾波器,濾除空間干擾信號。通過對空間電磁環(huán)境以及局部放電信號的特性進(jìn)行研究,給出了低噪聲放大器和檢波器的最佳工作頻率。在該頻率分別對低噪聲放大和對數(shù)檢波進(jìn)行匹配電路設(shè)計,實現(xiàn)UHF局部放電傳感器在該頻率處于最佳工作狀態(tài)。(4)在實驗室對UHF局部放電傳感器前端射頻模塊的匹配電路以及濾波器性能進(jìn)行測試,將實測結(jié)果與仿真模擬結(jié)果進(jìn)行對比分析。將不同濾波器加在UHF局部放電傳感器前端,在現(xiàn)場對GIS設(shè)備中局部放電信號進(jìn)行測試,測試結(jié)果表明本文所設(shè)計的濾波器能有效濾除空間電磁信號干擾,提高傳感器的信噪比。
[Abstract]:At present, with the application of gas insulated composite switch (GIS) in high voltage system, there are more and more researches on GIS partial discharge detection. In this paper, the UHF (UHF) partial discharge detection method is studied, and the existing problems of this method are summarized. Because of the weak intensity of pulse signal generated when partial discharge occurs and the large interference of space electromagnetic environment to the detection of discharge signal, band-pass, high-pass and band-stop filters are designed by using ADS simulation software. Filter out interference signals in different frequency bands. By studying the space electromagnetic environment and the characteristics of partial discharge signal, the optimum working frequency of low noise amplifier and detector is given. Based on the theoretical analysis, the matching circuit of low noise amplifier and detector is designed at the optimum operating frequency, which makes the UHF partial discharge sensor in the optimal working state at this frequency. Finally, the designed RF circuit is tested. The test results show that the front-end RF circuit can effectively filter the spatial interference signal and improve the signal-to-noise ratio of the UHF partial discharge sensor. The main contents of this paper are as follows: (1) the application background of GIS equipment, the mechanism of partial discharge and the main causes of partial discharge are introduced. The present situation of UHF PD detection method and its advantages and disadvantages are described. (2) the theoretical knowledge of RF circuit design is briefly introduced. The basic principle of filter and matching circuit design is analyzed in order to lay a theoretical foundation for practical filter and matching circuit design. (3) the composition and function of RF circuit in front end of UHF partial discharge sensor are introduced. Because of the large interference caused by the space electromagnetic signal to PD detection, the ADS simulation software is used to design bandpass, high-pass and band-stop filters to filter the spatial interference signals. By studying the space electromagnetic environment and the characteristics of partial discharge signal, the optimum working frequency of low noise amplifier and detector is given. The matching circuit of low noise amplification and logarithmic detection is designed at this frequency. The UHF partial discharge sensor is in the optimal working condition at this frequency. (4) the matching circuit and filter performance of the RF module in the front end of the UHF partial discharge sensor are tested in the laboratory. The measured results are compared with the simulation results. Different filters are added to the front end of the UHF partial discharge sensor and the partial discharge signals in the GIS equipment are tested in the field. The test results show that the filter designed in this paper can effectively filter the spatial electromagnetic signal interference and improve the signal-to-noise ratio of the sensor.
【學(xué)位授予單位】：西安電子科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TM595

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 唐炬,朱偉,孫才新,侍海軍,魏鋼;GIS局部放電的超高頻檢測[J];高電壓技術(shù);2003年12期

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本文編號：2251960