Research On Dynamic Balance Technology And System For Rigid Rotor

In the rotating mechanical system, the rotor is an important part. The vibration of unbalanced rotor is the main reason of equipment vibration, noise and damage. Over sixty percents of all the machinery fault are due to unbalanced rotor. Therefore, it is very important to perform dynamic balance test on rotor to reduce fault of equipments and make work safely.There are two ways of dynamic balance:equilibrator and field dynamic balance. Field dynamic balance is used more and more widely because of its convenience, low price and efficience. At the present, most of dynamic balance instruments are based on single chip microcomputer. The low performance on data acquisition and signal processing limits the range of rotator’s speed. The accuracy and speed of dynamic balance of those instruments can not meet the demand of modern dynamic balancing test.this paper has researched the key technologies of dynamic balancing test and developed a balancing system by combining the technique of field dynamic balance, digital signal processing and virtual instruments based on NI data acquisition equipment.Based on the dynamic balance theory, the key technologies were studied, including accurate measurement of speed, adaptive whole cycle sampling of vibration signal, extracting unbalance signal by correlation filter, extracting the amplitude and phase base on traditional FFT, entire cycle intercept DFT, and cross correlation. These algorithms were developed on Lab VIEW platform, and verified by simulation and experiment.The rigid rotor dynamic balance test system was developed on Lab VIEW platform, whose hardware contains NI USB-9234data acquisition device, Personal Computer. The SQL database was employed in the system for managing the test data. Producer/consumer software design mode was used to ensure reliability and improve the test accuracy. The following functions have been accomplished in the system, such as parameters setting, data processing algorithms, dynamic balance diagnosis, single and double dynamic balancing test and the data management, etc.The dynamic balancing test was performed on the ZT-3vibration test equipment, in order to verify the system’s effectiveness. The main works were done, included calibrating sensors, setting up the dynamic balancing test platform, regulating and analyzing the dynamic balance in conditions of different speed. The results indicate that the dynamic balancing test system has good test precision, fast computing speed, better stability and operability.