基于耦合随机共振的涡街信号检测方法研究  

Research on the Vortex Signal Detection Method Based on Coupled Stochastic Resonance

作　　者：章圣意 黄咏梅 ZHANG Shengyi;HUANG Yongmei(Zhejiang Cangnan Instrument Group Co.,Ltd.,Cangnan 325800,China;College of Metrology Technology and Engineering,China Jiliang University,Hangzhou 310018,China)

机构地区：[1]浙江苍南仪表集团股份有限公司,浙江苍南325800 [2]中国计量大学计量测试工程学院,浙江杭州310018

出　　处：《自动化仪表》2018年第7期65-69,共5页Process Automation Instrumentation

摘　　要：涡街流量计在工业现场使用时,输出信号中会叠加噪声信号。涡街信号容易被噪声淹没,使小流量测量受限。近年来,基于非线性理论的随机共振(SR)方法为微弱信号检测提供了新途径。非线性系统设计及参数确定是其成功应用的关键。提出了一种基于遗传算法的耦合随机共振系统优化控制方法。对耦合系数、控制系统参数以及变换尺度3个参数进行并行优化,提高了输出信号的功率谱幅值,增强了对微弱信号的检测能力。理论分析和数值仿真结果表明:该方法能够自适应地对不同频率周期信号进行处理,快速搜索到参数最优值。将该方法用于小流量涡街信号分析,能够在信号微弱、噪声强的情况下有效提取涡街信号的特征频率,并获取流量值。该研究成果适用于其他涉及强噪声中微弱信号检测领域,对拓宽随机共振应用范围、解决工程实际问题具有重要意义。In practical application,noise signal may superimpose on the output signal of vortex flowmeter,especially in the low flow rate measurement,the vortex signal is easily submerged by noise. In recent years,the stochastic resonance（ SR） method based on nonlinear theory provides the new method for weak signal detection. The key points of the successful SR application are the design of the nonlinear system and the determination of parameters. An optimal control method of coupled stochastic resonance system based on genetic algorithm is proposed. Three kinds of parameters,the coupling coefficient,control system parameters and transformation scale are optimized in parallel to improve the power spectrum amplitude of the output signal and enhance the detectability of weak signal. The theoretical analysis and numerical simulation show that the method can adaptively process the periodic signal with different frequency and obtain the optimum parameters quickly. The method is applied to analyze the lower flow rate vortex signal. It can effectively extract the characteristic frequency of vortex signal from the weak signal with strong noise and obtain the flow rate. The research achievement can be used in other weak signal detection areas related to the strong noise.The result is meaningful to broaden the application area of SR and it is of great significance to solve practical engineering problems.

关 键 词：涡街流量计 频率检测 随机共振 遗传算法 降噪 微弱信号检测 

分 类 号：TH814[机械工程—仪器科学与技术] TP274[机械工程—精密仪器及机械]