The Measurement And Analysis System Of Electrical Machine's Vibration And Noise Based On LabVIEW

The requirement to measure, analyze and reduce the noise and vibration of electrical machines involves great concern around the world as the electrical machines are more and more widely used in industry, agriculture and other fields. And compared with traditional instrument technology, virtual instrument technology is widely used in engineering measurement because of many advantages, such as better performance and strong expansibility. Thus, it is an available solution to develop a system to measure and analysis noise and vibration of electrical machines using virtual instrument technology.In this dissertation a measurement and analysis system of noise and vibration of electrical machines is developed using virtual instrument technology. The main works can be divided into three parts. The components of the hardware and software of the system are discussed in the first and second part. And three experiment are designed to verify the correctness and validity of the system. Following are the main works of this dissertation.1. The hardware. The components of the hardware are discussed, and a system including sensors, signal conditioning circuit and data acquisition card is established. It is the foundation of the whole system, and is used to acquire the noise and vibration signals of the electrical machines.2. The software. A software is developed using the virtual instrument programming language LabVIEW, and several functions are realized including signal acquisition, signal display, signal processing, fault diagnosis, report generation. Four signal processing tools are studied, including fast fourier transformation, power spectrum analysis, fractional octave analysis, wavelet transform analysis, and their application in noise and vibration signal processing is conducted. SVM in electrical machines fault diagnosis is studied, And a Least Square-Support Vector Machine(LS-SVM) based on fault diagnosis system is designed.3. Experiments research. The correctness of the signal acquisition, signal processing and the fault diagnosis is verified,, and the validity to fault diagnosis is studied using LS-SVM.At last, the dissertation concludes with a summary and perspectives of future research of the measurement and analysis system.