高压直流输电线路可听噪声测量数据有效性判定方法

Effectiveness Determination Method of Audible Noise Test Data for High Voltage DC Transmission Lines

在户外测试高压直流输电线路的可听噪声时,由于受到背景噪声的影响经常测得较多的无效数据,给后期的数据分析造成了较大的困难。为此,对特高压直流可听噪声信号的时域特性进行了统计和分析,设计了有限长单位冲击响应(FIR)数字滤波器,基于滤波后得出的阀值来判定数据的有效性。最后基于人工测量的方法对提出的无效数据判定方法进行了验证。结果表明:利用提出的输电线路可听噪声测试数据有效性的判定方法,将可听噪声测试数据中无效数据剔除后,仅会降低无效数据的最大值,而对50%值和95%值基本无影响,在工程误差允许范围内不会对后续的数据处理带来不良后果。因此提出的无效数据判定方法可为可听噪声测量和数据处理提供较大的帮助。

In tests of audible noises of transmission lines, a lot of invalid audible noise data due to the impact of back- ground noise obviously trouble the subsequent analysis of the test results. Therefore, we analyzed the time-domain characteristics of audible noise signals obtained from UHVDC lines, and designed a finite impulse response （FIR） filter to obtain threshold values for determining the validity of these data. This method for determining invalid audible noise data was also verified using some manual test data. The results show that using the proposed method to determine the effective audible noise data can only reduce the peak value which is invalid data; after eliminating invalid data from the audible noise test data, the 50% and 95% values are not affected. Thus, there is no adverse consequences for the follow-up data processing while keeping errors within the engineering allowance. Therefore, the proposed determination method of invalid audible noise data can help to measure audible noise and to process the test data.