Stajuda Mateusz, García Cava David, Liśkiewicz Grzegorz
School of Engineering, Institute for Infrastructure and Environment, University of Edinburgh, Thomas Bayes Road, Edinburgh EH9 3FG, UK.
Institute of Turbomachinery, Lodz University of Technology, Wólczanska 219/221, 90-924 Lodz, Poland.
Sensors (Basel). 2022 Mar 7;22(5):2063. doi: 10.3390/s22052063.
Aerodynamic instabilities in centrifugal compressors are dangerous phenomena affecting machine efficiency and in severe cases leading to failure of the compressing system. Quick and robust instability detection during compressor operation is a challenge of utmost importance from an economical and safety point of view. Rapid indication of instabilities can be obtained using a pressure signal from the compressor. Detection of aerodynamic instabilities using pressure signal results in specific challenges, as the signal is often highly contaminated with noise, which can influence the performance of detection methods. The aim of this study is to investigate and compare the performance of two non-linear signal processing methods-Empirical Mode Decomposition (EMD) and Singular Spectrum Analysis (SSA)-for aerodynamic instability detection. Two instabilities of different character, local-inlet recirculation and global-surge, are considered. The comparison focuses on the robustness, sensitivity and pace of detection-crucial parameters for a successful detection method. It is shown that both EMD and SSA perform similarly for the analysed machine, despite different underlying principles of the methods. Both EMD and SSA have great potential for instabilities detection, but tuning of their parameters is important for robust detection.
离心式压缩机中的气动不稳定是影响机器效率的危险现象，在严重情况下会导致压缩系统故障。从经济和安全的角度来看，在压缩机运行期间快速且可靠地检测不稳定是一项极其重要的挑战。利用来自压缩机的压力信号可以快速指示不稳定情况。使用压力信号检测气动不稳定会带来特定的挑战，因为该信号通常被噪声严重污染，这可能会影响检测方法的性能。本研究的目的是研究和比较两种非线性信号处理方法——经验模态分解（EMD）和奇异谱分析（SSA）——用于气动不稳定检测的性能。考虑了两种不同特性的不稳定情况，即局部进气回流和整体喘振。比较集中在检测的稳健性、灵敏度和速度上，这些是成功检测方法的关键参数。结果表明，尽管这两种方法的基本原理不同，但对于所分析的机器，EMD和SSA的性能相似。EMD和SSA在不稳定检测方面都有很大潜力，但对其参数进行调整对于稳健检测很重要。
