6自由度电液振动台控制策略研究

Control strategy of a 6-DOF hydraulic shaker

为提高6自由度电液振动台的控制精度,在传统6自由度控制回路中增加两路扭曲控制回路,采用扭曲控制策略控制平台振动。基于扭曲控制策略,对传统压力镇定控制器进行改进,将相互关联的8个参数缩减为2个相互独立的参数。正弦振动试验结果表明,采用扭曲控制策略能够明显改善振动台系统低频段的加速度均匀度和横向分量指标,改进后的压力镇定控制器能够有效削弱系统中各液压缸之间的内力。

Torsion control strategy of a 6-DOF(degree-of-freedom)hydraulic shaker was presented to improve the control precision of the system.Two torsion control loops were added to the original 6-DOF control loops.The force balance controller was improved based on the torsion control strategy.The number of the controller parameters was reduced from eight to two,and the two parameters were independent and could be adjusted individually.Sine vibration tests were run in one 6-DOF hydraulic shaker with the new algorithm.Test results showed that the torsion control strategy is favorable to improve the performance indices of acceleration evenness degree and acceleration transverse components in the lower-frequency band of the system;the improved force balance controller can reduce the inner forces among the eight cylinders effectively.