CAJ | 학술논문

针对碰摩故障诊断中转静碰摩响应消噪及特征提取构造分段圆弧平滑阈值函数，利用小波、小波包及双树复小波（Dual-tree Complex Wavelet）分别对非平稳信号降噪处理，以信噪比为指标判断降噪效果。结果表明，构造的阈值函数消噪具有高效性。通过计算单转子局部碰摩动态响应，用双树复小波对位移响应进行特征提取。与小波及小波包相比，双树实小波近似解析性及采样插值具有互补特点，能完整提取动态响应特征，减少信息丢失。并用仿真及转子碰摩实验验证该方法的有效性。
침대팽마고장진단중전정팽마향응소조급특정제취구조분단원호평활역치함수，이용소파、소파포급쌍수복소파（Dual-tree Complex Wavelet）분별대비평은신호강조처리，이신조비위지표판단강조효과。결과표명，구조적역치함수소조구유고효성。통과계산단전자국부팽마동태향응，용쌍수복소파대위이향응진행특정제취。여소파급소파포상비，쌍수실소파근사해석성급채양삽치구유호보특점，능완정제취동태향응특정，감소신식주실。병용방진급전자팽마실험험증해방법적유효성。
The de-noising of rub-impact response signals of a rotor-stator system and its characteristics extraction are key problems of rub fault diagnosis.A piecewise smooth threshold function was constructed for wavelet de-noising,and non-stationary signals were de-noised separately by using Wavelet,Wavelet packets and dual-tree complex wavelet transform(DTCWT).SNR (signal to noise ratio)was taken as an index to evaluate the de-noising effect.The results reveal that the constructed threshold function is highly active in de-noising.As an example,the dynamic response of a single rotor under rub-impact was calculated and decomposed by DTCWT.The simulation and experiment results show that the dynamic response can be exactly derived due to the complementary property between approximate analyticity and sampling interpolation of DTCWT.It is also proved that the proposed method is effective.