液压机批量成形控制策略

为了提高批量成形金属产品的塑性成形性能,建立了金属液压成形系统的数学模型,并针对追踪周期性位移信号存在滞后和周期性误差的问题,提出了一种基于重复控制和输出反馈的复合控制策略(ROF控制),以提高系统性能,并在金属成形模拟液压实验平台上验证了在ROF控制策略作用下的液压缸位移、速度和加速度响应特性,与PID控制进行了对比分析。实验结果表明,采用ROF控制策略,其系统追踪精度能达到0. 05 mm,两个工作循环周期后,追踪过程基本无滞后,能保证金属按指定谐波信号成形,最终能有效地提高批量成形金属件的性能。

Batch forming control strategy of hydraulic press

In order to improve the plastic forming performance of metal products by batch forming,a mathematical model of metal hydraulic forming system was established. Aiming at the problem of hysteresis and periodic error in tracking periodic displacement signals,a compound control strategy( ROF control) based on repeated control and output feedback was proposed to improve the system performance.Then,the hydraulic cylinder displacement,velocity and acceleration response characteristics under the ROF control strategy were verified by the experimental platform for simulating metal hydraulic forming,and it was compared and analysed with the PID control strategy. The experimental results show that the system tracking accuracy achieves 0. 05 mm by the ROF control strategy,and after two working cycles,there is almost no hysteresis in the tracking process. Thus,it ensures that the metal is shaped by the specified harmonic signals to improve the performance of metal parts by batch forming effectively.