流动式架桥机制动液压系统设计及动态特性分析

随着桥梁制造业的发展,建筑材料的运输安全获得关注。但工程中的路况复杂,流动式架桥机在行驶中存在安全隐患。为了防止这种情况发生,研究在比例积分微分控制算法中添加感应电磁铁,并在制动液压系统中添加磁屏蔽装置,用以削弱电磁铁产生的励磁电流。最后,将混合系统在Bemach数据集上进行实验,并与极限梯度提升等3种系统进行比较。在下坡时4种系统的制动时间分别为14,25,19,21 s,混合系统的制动位移为8 m;上坡时混合系统的制动时间和位移分别为8 s和3 m,在4种系统中表现最优。实验结果表明,研究提出的混合系统具有显著优势,能对架桥机进行有效制动。

Influence of DSP controller on performance of a permanent magnet brushless AC drive in flux-weakening mode

The flux-weakening performance of a permanent magnet brushless AC drive was investigated using both floating-point and fixed-point DSP controllers. A significant current oscillation was observed when the drive was operated at high-speed in the flux-weakening mode with the fixed-point DSP. The investigation showed that this was due to the on-line compensation of the winding resistance voltage drop and quantisation errors associated with the fixed-point architecture of the DSP. A simple look-up table scheme is proposed to eliminate the oscillation and to achieve extended flux-weakening capability.