BQK-50型动平衡机的测量电路

The Measuring Circuit for BQK-50 Type Dynamic Balancing Machine

本文研究了设计半硬支承动平衡机测量电路的技术关键,论述了其关键电路——跟踪带通滤波器、锁相环和相敏检波器的功能及设计原理。

In the measuring circuit proposed, a bandpass tracking filter is arranged in front of the phase-sensitive detector (PSD). The central frequency of the filter is capable of tracking the variation of the signal frequency. Value Q of the filter can be made high to improve the signal-to-noise ratio of the unbalanced signal. By a phase-locked loop, a reference pulse is converted into two orthogonal square waves as reference signals for the PSD. The signals are of good orthogonality and duty ratio and are capable of tracking the variation of the rotor speed as well. Both the amplitude and phase of the unbalanced signal are detected by the PSD with coherent detection.