基于频域辨识模型的新型幂次趋近律滑模控制

Novel sliding mode control with power reaching law based on frequency domain identification models

针对刚柔耦合系统传统理论建模过程复杂、模型不准确问题,采用频域子空间方法来辨识实验系统中的电机模型和压电片模型。同时针对传统趋近律的到达时间较长以及抖振问题,提出一种新型幂次趋近律的滑模控制。理论分析表明在不影响抖振情况下可缩短到达时间和扩大传统幂次趋近律参数α的范围。考虑柔性梁振动特性对系统性能的影响,采用子滑模面的方法来设计滑模控制器。最终,实验结果表明所设计控制器能够实现对中心刚体角度的快速跟踪,并且能够快速抑制柔性梁的振动。

Considering the complexity and inaccuracy of traditional theoretical modeling for rigid-flexible couple system, the frequency domain subspace method was used to identify the motor＇ s model and piezoelectric ceramic piece＇ s model in the experimental system. Due to the problem of chattering and long reaching time of traditional reaching law, a novel sliding mode control with power reaching law was proposed. Theoretical analysis shows that the reaching time can be shortened and the range of traditional power reaching law＇ s parameter α can be expanded, which will not affect the chattering. Considering the effect of vibration characteristics of flexible beam on system performance, the method of sub-sliding surface was used to design the sliding mode controller. Lastly, experimental results show that the designed controller can track the angle of the center of the rigid body rapidly and suppress the vibration of the flexible beam quickly.