基于SDFT和自适应三参数陷波器的快速机械谐振抑制

Fast Suppression of Mechanical Resonance Based on SDFT and Adapting Three Parameters Notch Filter

伺服系统中发生中高频机械谐振时一般采用自适应陷波器进行抑制。传统的两参数陷波器方案易引入较大的相位延迟,而且抑制速度难以满足高性能伺服的需求。针对此问题,提出了一种改进的陷波器方案,通过加入陷波深度参数来调整陷波中心频率处的振幅衰减,降低了陷波器带来的相位滞后。并提出了一种基于SDFT算法的谐振频率检测方案,通过在每次采样后获取系统幅频谱的变化过程来检测系统谐振频率,大大缩短了谐振频率检测耗时。理论和实验证明新方案能更快、更稳定的实现机械谐振的自适应抑制。

Adaptive notch filter is generally used to suppress the high-frequency mechanical resonance in servo system. However,the traditional scheme will bring large phase delay and is difficult to meet the highperformance servo＇sneeds of suppression speed. To solve this problem,the notch depth parameter was brought to adjust the amplitude attenuation at the notch center frequency and reduce the phase delay. Then,a detection scheme of resonant frequency based on SDFT was proposed. The system resonant frequency was detected by acquiring the variation of system amplitude spectrum after each sampling,which greatly shortens the detection time of the traditional scheme. It is shown experimentally and theoretically the new scheme is faster and more stable.