滞后相位

Generalized predictive control is a kind of advance control methods that is of strong robustness, can overcome the time delay of system effectively and is suitable to unstable non-minimum phase system. But it has the shortcoming of large computation load because of online solving the Diophantine equation, inverse matrix and recursion solution by Least squares. So four kinds of fast algorithms of GPC that don't need the mathematical model of plant and are highly real-time are proposed in the paper. They have laid the rationale for the application of GPC to systems that need fast response.

广义预测控制是一种鲁棒性强、能够有效地克服系统滞后、可应用于开环不稳定非最小相位系统的先进控制算法，但由于它需要Diophantine方程计算、矩阵求逆和最小二乘的递推求解，因此计算量很大，本文针对此缺陷提出四种不基于对象模型且实时性高的广义预测控制快速算法，为广义预测控制应用于实时性要求高的快速系统奠定了理论基础，具体研究工作如下。

Results show:(1) coupling of elastic deflections with rigid motions is distinctive;(2) computations of two methods are in good agreement with test data, when rotation angle is small;(3) when rotation angle is large, couplings increase distinctly and the differences between the results of the two computational methods increase;(4) the bending stiffness has evident effect on the coupling, and the coupling will increase with the decrease of bending stiffness;(5) in case of the blade is relatively soft, the calculated values of phase lag and amplitude augment based on infinitesimal rotation will exist.

计算分析表明：(1)弹性桨叶存在较明显的刚性运动和弹性变形耦合；2）挥舞角较小时，两种处理方法计算结果一致，均与试验数据吻合较好；(3挥舞角较大时，刚柔耦合增强，两种处理方法的计算值差别较为明显；(4)桨叶弯曲刚度对桨叶刚柔耦合特性有较明显影响，刚度越小，耦合越强；(5)桨叶如果比较柔软，小转角处理方法计算值相对有限转角处理方法，相位滞后、幅值增加均较为明显，计算桨叶动响应时需引起注意。

Based on the test and analysis of phase lag property, the dyramie property of the system is corrected by circuit.

执行系统经硬件电路校正后，仍存在一定的相位滞后。

The closed-loop bandwidth of the system reaches 10Hz which assures the error of amplitude less than ±10% and the lag of phase less than 10°.

系统的性能指标达到幅值误差在±10%以内、相位滞后小于10°时，闭环频宽为10Hz。

In the AC servo control system, using digital low-pass filter can restrain current feedback noise and improve the resolving power of speed feedback, but it may lead to phase lag of feedback signal and directly influence the response speed.

交流伺服控制中采用数字低通滤波可以抑制电流反馈噪声，提高速度反馈分辨率，但同时会带来反馈信号的相位滞后，将直接影响响应速度。

The numerical results show that the ocean models in diurnal band are more stable than those in semidiurnal band, and the correction of the change in tidal height plays a significant role in determining accurately the phase lag of the tidal gravity.

数值结果说明周日频段内的海潮模型要比半日频段内的模型更加稳定，实施验潮站潮位高变化改正对精密确定重力固体潮相位滞后起重要作用。

However, phase lead may also improve accuracy, and phase lag may improve

确性，相位滞后补偿也可以提高系统的稳定性。

In terms of hardware bring forward the zero-crossing detection to compensate for the phase lag caused by filter.

硬件上通过提前过零检测来补偿加重滤波器带来的相位滞后；软件上加入判定过零点真伪的功能。。。

In terms of hardware, bring forward the zero-crossing detection to compensate for the phase lag caused by filter.

硬件上通过提前过零检测来补偿加重滤波器带来的相位滞后；软件上加入判断过零点真伪的功能，以及先检测过零点再切换后级逆变桥的方法有效避免错误过零点造成的锁相失败问题，达到了很好的效果。

Secondly, signal after filtered is discussed from several respects of time domain, frequency domain and phase lag. We can conclude practical range of each filter with respect to different applied condition.

从时域、频域和相位滞后等几方面对滤波处理后的信号进行了分析，得出了各种滤波法适用的范围以及在实际使用中应注意的问题。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。