A measurement system based on virtual instrumentation for field dynamic balancing of rotors

A network system for measuring the vibration caused by unbalance in the rotor is designed based on virtual instrumentation. A novel method which integrated the influence coefficient method (ICM) and mode-balancing method (MBM) is presented, which is used for field balancing of both the rigid and flexible rotors. Adopting a modular design concept, we developed a field dynamic balancing instrument consisting of both hardware and software components. The modules include switched-capacitor tracking filter, differential amplifier, multiple frequency phase-locked circuit and data transmission and are designed in a hardware system. The procedures in the software system are composed of spectrum analysis, dynamic balancing calibration, dynamic balancing test, video device driver and network transmission. Experimental results illustrate the hardware circuit can effectively reduce the error caused by white noise and temperature change. The software system responds rapidly with an excellent human-computer interaction interface. The percent of removed unbalance amount of one correction can reach 90% and the dynamic range can be as much as 90 dB.