电力电容器噪声控制关键技术研究

发布时间：2019-04-28 07:14

【摘要】：随着我国电力行业的不断发展,特别是高压、特高压直流输电项目的快速发展,电力电容器作为滤波与无功补偿装置被广泛用于直流输电的换流站中。换流站的电容器装置通常由多个电容器塔架组成,每个电容器塔架又由上百台电容器阵列构成,其中单台电容器辐射的噪声约为60d B。因此,由成千数百台电容器叠加辐射的噪声则高达90d B。目前,对于换流站中的电容器装置噪声污染问题主要采取声屏障的被动隔声办法,声屏障治理办法不仅造价高而且没有从噪声源上进行降噪,因此研究单台电力电容器的可听噪声控制方法具有重要的意义。本文的主要研究内容如下:1、研究了基于有限元理论的电力电容器振动与噪声仿真方法。首先对电力电容器的内部构造进行分析得到其振动仿真的激励条件,然后在LMS Virtual.lab软件中建立电容器有限元模型并进行振动仿真,紧接着将电容器结构振动仿真得到的电容器外表面法向振速与声学边界元法理论作为基础对电力电容器进行声学仿真,最后通过实验测试的方式验证仿真方法的可行性。2、研究了电流激励下电力电容器的噪声辐射比,有利于准确估算单台电力电容器的辐射噪声。首先在分析噪声辐射比理论的基础上应用振声频响函数法设计了电流激励下电力电容器噪声辐射比的测试与验证实验,并对测试结果进行分析研究。3、研究了电力电容器的芯子底面与壳体间设置减振器的噪声控制方法。首先基于机械阻抗法建立电容器结构振动的简化振动模型,然后根据电容器降噪量与电容器壳体振动之间的关系,以及波纹管的性能要求设计了一种波纹管减振器,最后制造含波纹管减振器的电容器样品,并对电容器样品进行降噪效果测试实验。实验结果表明:所设计的波纹管减振器件具有良好的减振降噪效果并与设计预期相符合,其中电容器底面方向降噪量最大,电容器底面对应的噪声测试场点降噪量达9d B。
[Abstract]:With the continuous development of power industry in China, especially the rapid development of high voltage and ultra-high voltage HVDC transmission projects, power capacitors are widely used in HVDC converter stations as filtering and reactive power compensation devices. The capacitor device of the converter station is usually composed of several capacitor towers, each of which consists of hundreds of capacitor arrays, in which the noise emitted by a single capacitor is about 60 dB. As a result, the noise emitted by the superposition of hundreds of capacitors is as high as 90 dB. At present, for the noise pollution of capacitor installation in converter station, the passive noise insulation method of sound barrier is mainly adopted. The control method of noise barrier is not only high cost but also does not reduce noise from the noise source. Therefore, it is of great significance to study the audible noise control method of a single power capacitor. The main contents of this paper are as follows: 1. The simulation method of vibration and noise of power capacitor based on finite element theory is studied. Firstly, the internal structure of the power capacitor is analyzed and the excitation conditions of its vibration simulation are obtained. Then the finite element model of the capacitor is established in the LMS Virtual.lab software and the vibration simulation is carried out. Then, based on the theory of normal vibration velocity and acoustic boundary element method of capacitor structure vibration simulation, the power capacitor is simulated. Finally, the feasibility of the simulation method is verified by the experimental test. The noise radiation ratio of power capacitor under current excitation is studied in this paper, which is helpful to accurately estimate the radiation noise of a single power capacitor. On the basis of analyzing the theory of noise radiation ratio, the measurement and verification experiment of noise radiation ratio of power capacitor under current excitation is designed by using the method of vibroacoustic frequency response function, and the test results are analyzed and studied. The noise control method of setting shock absorber between core bottom and shell of power capacitor is studied. Firstly, the simplified vibration model of capacitor structure vibration is established based on mechanical impedance method, and then a corrugated tube damper is designed according to the relationship between capacitor noise reduction and capacitor shell vibration, and the performance requirements of corrugated tube, and then a kind of corrugated tube vibration absorber is designed according to the relationship between capacitor noise reduction and capacitor shell vibration. Finally, the capacitor sample with corrugated tube damper is manufactured, and the noise reduction effect of the capacitor sample is tested. The experimental results show that the designed bellows damping device has a good damping and noise reduction effect and accords with the design expectations, in which the capacitor bottom direction noise reduction is the largest, the noise corresponding to the bottom surface of the capacitor noise test field point noise reduction amount up to 9 dB.
【学位授予单位】：桂林电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TM531.4

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