增量式编码器测速的典型问题分析及应对策略

作为一种常用的测速设备,增量式编码器在电机控制中发挥着重要作用。为了能够更好地利用编码器提高测速和控制效果,本文讨论了编码器应用中常见的几种典型问题。首先,本文根据T法和M法测速原理确定了测速方法的选择依据,根据查询方式和中断方式程序执行的特点分析了如何合理选择软件实现方式。然后,针对低分辨率编码器的情况,提出了一种连续中断T法测速方法,该方法实现比较简单,可以最大程度地利用编码器脉冲、减小测速延时。同时以科研过程中实际遇到的问题展示了编码器安装误差对测速精度的影响,并分析了这种情况下如何选取测速方法。最后,在异步电机试验台上进行了实验,实验结果证明了本文对上述问题的分析及所提应对策略的合理性和有效性。

Typical Issues Analysis and Corresponding Strategy for Incremental Encoder Speed Measurement

Incremental encoder plays an important role in motor drive system.In order to reveal the potential problems in encoder speed measurement,this paper studied several typical issues.First,the basic measurement methods and their merits/demerit are given,and how to choose measurement method and software realization pattern are discussed.Then,for low resolution encoder,a consecutive interrupt T-method(CIT-method) is proposed,with which speed sample frequency can be increased and close-loop control performance is improved.As for installation errors of high resolution encoder,this paper gives a way to elude feedback error by choosing suitable measurement method,and it does work to obtain a better result with the same encoder.At last,experiment results are listed to imply the validity of these analysis and strategies.