光纤参量振荡器的自动反馈控制技术研究

为了实现光纤参量振荡器(FOPO)的高精度稳定时钟信号提取,该文首次开展了基于闲频光功率的自动反馈控制实验,其中自动反馈控制单元由闲频光采集模块、自动控制信号处理模块以及延迟线驱动模块组成。测量了12.5 Gb/s归零(RZ)信号输入时自动反馈控制FOPO提取的时钟信号质量,其均方根(RMS)相位抖动值为0.92 ps,时钟提取精度明显高于之前的手动反馈控制系统。

反馈式数字AGC的FPGA优化实现

新的全数字式反馈自动增益控制(AGC)算法,采用硬件描述语言VHDL进行FPGA实现,MODELSIM仿真测试实验结果表明,该新方案实现简单、速度快,具有更小的资源占用、更快的收敛速度,有效地解决了无线通信系统中各种因素(距离、信道衰减、电磁干扰等)所造成的数字信号传输问题,具有良好的工业应用前景。

夹层玻璃生产线预压温度自适应控制系统

长期以来夹层玻璃生产线自动化程度不高,质量难以控制。本文通过在玻璃出口安装的2个红外温度探测传感器反馈的出口玻璃温度来自动控制3个加热室的温度,人为干预的程度低,实现温度速度控制的全自动化,从而提高生产效率及产品合格率。

液压AGC控制在轧钢中的研究

精轧控制主要包括以下几方面的控制:主速度控制、活套控制、厚度控制和板型控制。液压AGC控制系统对带钢生产线来说有着至关重要的作用,直接影响到产品的厚度精度。文章介绍了精轧机组液压AGC软件包控制思想的实现,对轧钢设计具有参考价值。

光反馈双路自动控制声光调Q驱动器

提出了新型的光反馈双路自动控制声光调Q驱动器方案。它能够同步控制声光Q开关和LD抽运源的运转,实现根据测出的上一次Q开关打开至光脉冲产生间隔自动控制下一次调Q持续时间的功能,并具有10W以上的功率输出和15 ns(1个射频驱动振荡周期)内的声光Q开关响应时间的优良性能。可以在保持光脉冲性能、节省能源、高热稳定性的前提下,提升声光调Q全固态激光器在各种环境下的稳定性和易调节性。

基于PLC和组态王的HCN双激光器功率稳定监控系统

HCN单激光器和转动光栅形成的差频信号一般不大于100 k Hz.HCN双激光器较之单激光器和转动光栅系统可以很容易的获得MHz量级的差频信号,进而可以研究更高时间分辨率的物理现象.但是HCN双激光器功率和频率都不稳定,功率稳定是频率稳定的前提,所以必须先保证HCN双激光器功率的稳定.本文以稳定功率为目标结合双激光器的特点,设计了一套双激光器功率的自动反馈控制系统及远程控制系统.本系统主要有西门子S7-200PLC、电动平台、肖特基势垒二极管和上位机等组成.实验表明这种方法可以长时间地使HCN双激光器稳定在高功率状态.

联合收割机工作效率的研究

我国作为一个农业大国,伴随着工业自动化的飞速发展,新生代农业对农业生产工具提出了更高的要求,要求生产机械化、自动化。联合收割机就是在该背景下应运而生。但随着联合收割机应用场合日益广泛,整体上联合收割机的工作效率不高,甚至在不同工况下按同一模式工作,使得收割机故障频发、机械损耗严重,甚至损坏收割机。因此,需要结合收割机工作负荷、实际工况,尽可能的实现对其自动化控制,保障收割机工作在较理想的工作状态,就是结合自动反馈控制系统,实现对收割机自动化控制,提高收割机工作效率,从何实现节能、环保、高效的农业自动化生产。

半钢子午线轮胎挤出胎侧合格率的提升

分析影响半钢子午线轮胎挤出胎侧合格率的因素,并提出相应的解决方法。通过修改口型流道和重新设计预口型,解决了左右两条挤出胎侧宽度差较大问题。通过采用胎侧宽度自动反馈控制系统,胎侧宽度波动误差从±2 mm减小到±1 mm,提高了胎侧宽度的精度和扫描合格率,显著减少了胎侧返回胶。通过合理匹配各挤出螺杆转速及对口型板局部进行倒角,有效降低了香蕉形胎侧的产生几率。通过安装热刺孔机,解决了成品轮胎产生较多气泡问题。

Adaptive Neural Network-Based Control for a Class of Nonlinear Pure-Feedback Systems With Time-Varying Full State Constraints

Abstract--In this paper, an adaptive neural network （NN） control approach is proposed for nonlinear pure-feedback sys- tems with time-varying full state constraints. The pure-feedback systems of this paper are assumed to possess nonlinear function uncertainties. By using the mean value theorem, pure-feedback systems can be transformed into strict feedback forms. For the newly generated systems, NNs are employed to approximate unknown items. Based on the adaptive control scheme and backstepping algorithm, an intelligent controller is designed. At the same time, time-varying Barrier Lyapunov functions （BLFs） with error variables are adopted to avoid violating full state constraints in every step of the backstepping design. All closed- loop signals are uniformly ultimately bounded and the output tracking error converges to the neighborhood of zero, which can be verified by using the Lyapunov stability theorem. Two simulation examples reveal the performance of the adaptive NN control approach. Index TermsmAdaptive control, neural networks （NNs）, non- linear pure-feedback systems, time-varying constraints.

Improved Smith prediction monitoring AGC system based on feedback-assisted iterative learning control

The performance of Smith prediction monitoring automatic gauge control(AGC) system is influenced by model mismatching greatly in strip rolling process. Aiming at this problem, a feedback-assisted iterative learning control strategy, which learned unknown modeling error by using previous control information repeatedly, was introduced into Smith prediction monitoring AGC system. Firstly, conventional Smith predictor and improved Smith predictor with PI-P controller were analyzed. Secondly, on the basis of establishing of feedback-assisted iterative learning control strategy for improved Smith predictor, process control signal update law and control error were deduced, then convergence condition of this strategy was put forward and proved. Finally, after modeling the automatic position control system, the PI-P Smith prediction monitoring AGC system with feedback-assisted iterative learning control was researched through simulation. Simulation results indicate that this system remains stable during model mismatching. The robustness and response of monitoring AGC is improved by development of feedback-assisted iterative learning control strategy for PI-P Smith predictor.

航空蓄电池放电检验试验机的研制

本文详细介绍了新型航空蓄电池放电检验试验机的控制方案和系统工作原理 ,特别提到了单片机在该控制系统中的作用 。

Dynamical output feedback stabilization for neutral systems with mixed delays

This paper is concerned with the issue of stabilization for the linear neutral systems with mixed delays. The attention is focused on the design of output feedback controllers which guarantee the asymptotical stability of the closed-loop systems. Based on the model transformation of neutral type, the Lyapunov-Krasovskii functional method is employed to establish the delay-dependent stability criterion. Then, through the controller parameterization and some matrix transformation techniques, the desired parameters are determined under the delay-dependent design condition in terms of linear matrix inequalities (LMIs), and the desired controller is explicitly formulated. A numerical example is given to illustrate the effectiveness of the proposed method.

透析相关性低血压防治研究进展

透析相关性低血压（IDH）会降低透析的疗效,给患者带来不适,其发生率为20%~30%[1]。IDH的诊断必须满足下述两个条件之一：透析过程中收缩压至少下降20 mm Hg（1mm Hg=0.133k Pa）,或平均动脉压至少下降10 mm Hg。IDH与多种临床事件相关,如心律失常、血管通路栓塞和脑血管循环、肠系膜循环和冠脉循环缺血[2]。

Adaptive Stabilization for a Class of Feedforward Systems with Zero-Dynamics

This paper investigates adaptive state feedback stabilization for a class of feedforward nonlinear systems with zero-dynamics, unknown linear growth rate and control coefficient. For design convenience, the state transformation is first introduced and the new system is obtained. Then, the estimation law is constructed for the unknown control coefficient, and the state feedback controller is proposed with a gain updated on-line. By appropriate choice of the estimation law for the control coefficient and the dynamic gain, the states of the closed-loop system are globally bounded, and the state of the original system converges to zero. Finally, a simulation example is given to illustrate the correctness of the theoretical results.

新型数字电位器在NM7000B型仪表着陆设备中的应用

NM7000B型仪表着陆系统为挪威挪马克公司在NM7000A型设备基础上的升级产品，它区别于NM7000A型设备的一个最大特点就是，通过SDR（软件定义无线电）技术实现设备调整的数字软件化。为了实现SDR技术，NM7000B型设备广泛应用了新型的数字电位器。本文就是通过介绍X9258数字电位器的原理和在NM7000B中的具体应用，来使导航技术人员进一步了解和掌握该新型电位器，提高设备的维护能力。