基于压电传感器的管道泄漏信号可靠性识别技术研究

Research on Pipeline Leak Signal Reliably Identification Based on Piezoelectric Sensor

管道泄漏检测的可靠性主要取决于泄漏信号的信噪比,泄漏信号信噪比的提高主要由传感器和对信号的处理方法决定。在定量分析的基础上,得出了基于压电传感器的管道泄漏检测方法具有比基于压力传感器的负压波法更高的泄漏信号信噪比。通过信号分析,论证了平滑滤波对于提高泄漏信号信噪比的必要性,提出了用区间信号能量来突出泄漏信号的方法。分析比较了实际检测信号幅值、区间信号能量和区间信号平均能量的平方3种方法下泄漏信号的信噪比,提出了用基于区间信号平均能量平方的顺序能量比率法进行管道泄漏信号识别的方法。结果表明该方法可以极大地提高泄漏信号信噪比和泄漏检测可靠性。

The reliability of leak detection depends on signal noise ratio （SNR）, but the sensor and signal processing determine the SNR of leak signal. Based on quantitative analysis, it is concluded that piezoelectric sensor based leak detection has higher SNR than that of pressure transducer based negative pressure wave leak detection. Through signal processing, the necessity of moving average filter for SNR is demonstrated, and the method for characterizing leak signal with interzone signal energy is proposed. The SNRs of detected signal, interzone signal energy and the square of average interzone signal energy are compared. A leak detection method with sequential energy percentage based on the square of average interzone signal energy is proposed. Analysis results showed that the SNR of leak signal and reliability of system are improved greatly with this novel method.