基于STC89C52的高精度数字相位测量方法设计

在电气测量时,为了高精度检测相位,通过过零检相来获取2信号过零点时间间隔,采用脉冲填充法与STC89C52高速单片相结合的测量电路,计算出时间间隔的脉冲个数,进而求得相位差值;并引入锁相倍频电路,使基准填充脉冲随着信号频率而变化,消除了频率变化引起的误差;利用数据选择器对采样通道切换,实现了零点漂移的补偿.结果表明,相位测量精度可达±0.020.

The High-accuracy Digital Phase Place Measurement and Design Based on One-chip Computer

In electric measurement,in order to examine phase place precisely,two over-zero point time in tervals are obtained through over-zero examination.By adopting measurement circuit combining pulse pack with one-chip computer,the number of pulses of time intervals is calculated to get phase place difference.Phase locking double frequency circuit is introduced to make the datum pack pulse change with signal frequency so as to dispel the error caused by frequency change.Sampling passway is made to switch over with the data selector to fulfill the compensation of zero point drifts.The results show that phase place can reach the precision of ±0.20.