基于光电编码器的电机变周期速度观测器设计

针对光电编码器在伺服系统应用中速度估计易受系统振动干扰和存在量化误差的问题，设计了一种基于变采样周期观测器的速度估计算法.通过观测器的积分运算抑制振动干扰；通过采样周期和光电编码器脉冲的同步，使量化误差最小；为了减小观测器离散域极点变化对算法性能的影响，保证变周期观测器在较大速度范围保持较高精度，给出了一种观测器增益系数的计算方法.实验表明该算法可以在保证动态性能的同时，有效抑制振动和量化误差引起的估计误差，提高速度估计精度. 

Variable-sampling-rate observer for speed estimation of servo motors with optical encoders

Incremental encoders are heavily used as speed measurement sensors in servo motor systems. Speed estimation in these applications is frequently affected by system vibrations and quantization errors. To avoid this problem, a variable-sampling-rate observer was proposed. Instead of numerical differential operation used in the M/T method, the proposed procedure was based on numerical integration, so vibration noise could be effectively suppressed. In order to eliminate quantization errors, the observer adapts its sampling period with the generated encoder pulses in each calculation cycle. Varying sampling period changes the poles of the observer, which deteriorates the stability of the system, so a gain calculation procedure was given in order to maintain stability in wide speed range. Experimental result shows that the proposed observer can effectively reduce estimation error caused by quantization error and vibration, and obtain better precision while guaranteeing good dynamical performance.