Rotating Machinery Signal Processing Technology And Its Application In High Speed Auto-Balancing

In order to obtain higher machining precision and efficiency, rotating machines such as machine tool's spindle or turbo-machine are getting more intelligent and speedup. However, the centrifugal force resulting from unbalance mass is proportional to the square of the working speed. With the increase of working speed, a tiny unbalance mass of the cutting tool or grinding wheel will generate a huge unbalance force, which will result in sever vibration of high-speed machine tools and thus seriously affecting the machining precision. Therefore, it is of great importance to seek an efficient auto-balancing technique. Initially, accurate extraction of the amplitude and phase of the vibration signal is an important prerequisite for the realization of the system, which has a great influence on the balanced speed and accuracy of the system. Moreover, the weight number has also become a factor affecting the balance of efficiency. In order to achieve fast dynamic balance, no-trail weight balancing method has become the preferred one. Taking the above into consideration, the main contributions of this dissertation were summarized as follows:(1) Firstly, this dissertation describes the overview of the signal processing technology; secondly, this dissertation describes the integration method of acceleration signal which has been studied by domestic and foreign scholars, and the discussion is carried out from the time-domain method and frequency-domain method respectively. Finally, the current state of the no-trail weight balancing method is analyzed in detail, which lays the direction of this topic research.(2) A data collector is designed which has features such as spectrum analysis, partial swing compensation, full cycle data acquisition, the same frequency signal extraction and vibration overrun alarm, and three algorithms of tracking filter, mutual power and sinusoidal approximation are introduced.(3) According to a series of problems that frequently happen in the actual project site in the speed sensor and the displacement sensor, the acceleration signal integral method is studied.(4) In engineering field, the process of trail weight would lead to the waste of time and money. Thus, based on the finite element software, the dynamic analysis of the rotor is carried out from the aspects of critical speed, vibration mode, weighted response and so on.(5) Aiming at the three extraction algorithms of signal amplitude and phase, based on the pneumatic liquid type automatic balancing test platform for verification; according to the acceleration signal of two integral method, the integration accuracy of the two algorithms were compared on the electromagnetic type double disc balancing counterweight system test platform; in view of the dynamic characteristics of the rotor of the pneumatic liquid automatic balance system, the automatic balance experiment was carried out on the pneumatic liquid type automatic balancing test platform, which verified the correctness of the simulation results.