【摘要】 在非接触式高速旋转叶片振动实时监测系统中 ,要求 2 5 μm的振动位移测量分辨率 ,为采集电路的设计增加了很大的难度。由于信号处理系统采用固定频率脉冲填充法计数 ,实现定时时间的测量。因此采集系统的设计中要解决两个关键问题 ,一是计数频率达 10 0MHz的 2 4bit高速计数器的设计 ,二是要专门设计一种两次脉冲锁存的方法 ,对每个计数器的输出数据在 30ns时间间隔内锁存两次 ,完全解决了由于计数频率太高造成的数据锁存失误问题。锁存的数据由EPP接口采集到计算机中进行处理。实验证实了该系统性能良好 ,达到预定精度要求。更多还原

【Abstract】 In the non contact real time detection of high speed rotating blade,because of the required 25μm measurement accuracy of vibration distance,the design of data acquisition circuit is rather difficult.Fixed frequency pulses filling method is adopted to realize the measurement of tip timing.Two key points are solved in the design,one is the realization of 24 bit high speed counter whose counting clock is 100MHz;the other is a double pulse latching method being used to successively acquire the output data from counter twice at a interval of 30 ns each time,with the result that the error latching caused by too high counting frequency is eliminated.The data is acquired through EPP and then processed by computer.It has been proved by the experiment that the system is able to obtain the required accuracy.更多还原