抽油机悬点位移间接测量方法研究  

Research on Indirect Measurement Method of Polished Rod Displacement in Pumping Unit

作　　者：仲志丹[1] 孙勇军 庞永星 ZHONG Zhidan;SUN Yongjun;PANG Yongxing(Mechatronics Engineering College,Henan University of Science & Technology,Luoyang Henan 471003,China;Luo Yang Qian He Instrument Ltd,Luoyang Henan 471003,China)

机构地区：[1]河南科技大学机电工程学院,河南洛阳471003 [2]洛阳乾禾仪器有限公司,河南洛阳471003

出　　处：《机床与液压》2019年第8期151-156,共6页Machine Tool & Hydraulics

基　　金：河南省高等学校重点科研项目(15A460023);国家自然科学基金资助项目(50906022)

摘　　要：针对利用抽油机悬点加速度信号计算位移精度较差的问题,提出自适应噪声的完备集合经验模态分解(CEEMDAN)自适应降噪和极点对称模态分解(ESMD)去趋势项相结合的求解方法。首先使用CEEMDAN分解加速度信号,然后根据模态分量自相关函数与原始信号自相关函数的相关系数,确定噪声分量和有效分量的分界点;进一步采用小波阈值法提取噪声分量中有用信号,并基于排列熵的性质自适应确定小波分解的层数;重构所有模态分量实现降噪;再对消噪的加速度信号进行积分变换得到位移,最后使用ESMD剔除趋势项。仿真分析和实测数据结果表明,该方法比现有方法精度更高、自适应性更好。Aiming at the poor accuracy of displacement calculated by using polished rod acceleration signal in pumping unit, a new method combining complete ensemble empirical mode decomposition with adaptive noise(CEEMDAN) adaptive de-noising and(extreme-point symmetric mode decomposition) ESMD removing trend items was introduced. CEEMDAN was used to decompose acceleration signal;then according to the correlation coefficients between the autocorrelation function of the intrinsic mode functions and the autocorrelation function of the original signals, cut-off point of noise components and effective components was sought out;furthermore, useful signal in the noise component was extracted by using the wavelet threshold method, and the number of wavelet decomposition was determined adaptively based on the property of permutation entropy;all the intrinsic mode functions were reconstructed to realize de-noising;displacement was obtained by using the integral transformation method for de-nosing acceleration;finally ESMD was used to remove trend item. The simulation analysis and measured data show that the proposed method is more accurate and adaptive than the existing methods.

关 键 词：加速度信号 自适应噪声的完备集合经验模态分解 极点对称模态分解 位移信号 

分 类 号：TN911.7[电子电信—通信与信息系统]