Abstract：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.
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2012, Vol. 27 
