A high-resolution interpolator for incremental encoders based on the quadrature PLL method

This paper presents a new high-resolution interpolator for incremental enco ders based on the quadrature phase-locked loop method proposed by Emura, Un til now this method has been applied to controllers of high-precision servo mechanisms and has shown excellent performance. In this paper, we apply the method for the first time to an interpolator for incremental encoders. The experimental results show that high-speed interpolation is possible, with a maximum output frequency of 25 MHz-20 times higher than that of conventio nal interpolators, The interpolator proposed was also tested for noise reje ction with a high-speed numerically controlled gear grinding machine, and h as shown good noise rejection capability. This paper presents the design of the interpolator and the experimental results.