INDEPENDENT OPERATING SHAPE DETERMINATION ON ROTATING MACHINERY, BASED ON ORDER TRACK MEASUREMENTS

摘要

Operating shape analysis of vibration problems on rotating machinery has traditionally been limited to either steady state conditions or those run up/down conditions where the rotational force inputs (orders) are well separated in frequency. Recently new order tracking techniques based on both the Vold-Kalman tracking filter and the Time Variant Discrete Fourier Transform have been developed which allow the separation of very close or crossing orders. This paper presents a technique that has been developed for processing these order track results into linearly independent operating shapes. These results give the engineer an estimation of which and how many modes or independent inputs, the lesser of the two, are excited by the rotational inputs of an operating machine. This technique is based upon the singular value decomposition and the CMIF parameter estimation technique commonly used in modal analysis.