This paper discusses the problem of robust H∞ control for a class of nonlinear uncertain singular systems with time delays.Considering the nonlinear disturbance link to uncertain singular systems with time delays effects,the design idea of robust H∞ controller is presented.Using Lyapunov stability theory and linear matrix inequality (LMI) method,a robust H∞ controller design example of such nonlinear uncertain singular systems with time delays both in state and output is given.Under nonlinear uncertain functions satisfying Lipschitz condition,a sufficient condition of such nonlinear uncertain singular systems which are asymptotically stable and satisfy the robust H∞ performance is obtained.Finally,a numerical example is given to show the applicability of the proposed method.

关键词：控制器；时滞；非线性；奇异系统

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In many real world scenarios, the model of the controlled process changes over time. Clearly in such situations the parameters of the controller need to be adjusted to give an acceptable level of control system performance. Many adaptive control techniques exist to cope with such changes in system dynamics. Traditionally since PID controllers have been extensively used in industrial processes, the adaptation laws looked at changing the proportional, integral and derivative gains of the controllers. With the use of Fractional order PID controllers, both the gains and the differentiation and integration orders may be fine-tuned online, to achieve a better system performance. This chapter looks at integration of computational intelligence paradigms with fractional order adaptive control and the various advantages that this synergism can offer.

关键词：控制器；分数阶；增益调度；整序

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X-ray diffraction (XRD) is a powerful analysis method that allows researchers to noninvasively probe the crystalline structure of a material. This includes the ability to determine the crystalline phases present, quantify surface residual stresses, and measure the distribution of crystallographic orientations. The Structures and Materials Division at the NASA Glenn Research Center (GRC) heavily uses the on-site XRD lab to characterize advanced metal alloys, ceramics, and polymers. One of the x-ray diffractometers in the XRD lab (Bruker D8 Discover) uses three different x-ray tubes (Cu, Cr, and Mn) for optimal performance over numerous material types and various experimental techniques. This requires that the tubes be switched out and aligned between experiments. This alignment maximizes the x-ray tube s output through an iterative process involving four set screws. However, the output of the x-ray tube cannot be monitored during the adjustment process due to standard radiation safety engineering controls that prevent exposure to the x-ray beam when the diffractometer doors are open. Therefore, the adjustment process is a very tedious series of blind adjustments, each followed by measurement of the output beam using a PIN diode after the enclosure doors are shut. This process can take up to 4 hr to perform. This technical memorandum documents an in-house project to motorize this alignment process. Unlike a human, motors are not harmed by x-ray radiation of the energy range used in this instrument. Therefore, using motors to adjust the set screws will allow the researcher to monitor the x-ray tube s output while making interactive adjustments from outside the diffractometer. The motorized alignment system consists of four motors, a motor controller, and a hand-held user interface module. Our goal was to reduce the alignment time to less than 30 min. The time available was the 10-week span of the Lewis' Educational and Research Collaborative Internship Project (LERCIP) summer internship program and the budget goal was $1200. In this report, we will describe our motorization design and discuss the results of its implementation.

关键词：控制器；X射线衍射仪；机动光束对准

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2014年2季度，汽车行业政策变化主要有两个方面：首先，为促进大气污染防治，工信部定于2014年底废止国三柴油车产品公告，自2015年起国三柴油车产品将不得销售。同时，国务院在车用成品油配套升级方面也做出了进一步的部署，我国柴油车国三时代宣告结束，国四大幕正式拉开。第二，工信部发布《轮胎行业准入条件》（征求意见稿），从企业布局和规模要求、工艺、质量和装备、能源和资源消耗、环境保护、安全生产和职业卫生、公告管理等多个方面提出了准入要求。准入门槛的设定将加快推动轮胎行业结构调整，规范生产经营秩序，抑制低水平重复建设，引导行业持续健康发展。

关键词：汽车行业；环境综述

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This document specifies the data interface for TSAFE, the Tactical Separation-Assured Flight Environment. TSAFE is a research prototype of a software application program for alerting air traffic controllers to imminent conflicts in enroute airspace. It is intended for Air Route Traffic Control Centers ('Centers') in the U.S. National Airspace System. It predicts trajectories for approximately 3 minutes into the future, searches for conflicts, and sends data about predicted conflicts to the client, which uses the data to alert an air traffic controller of conflicts. TSAFE itself does not provide a graphical user interface.

关键词：控制器；TSAFE接口；控制文档

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Shunt active power filters have been introduced as a way to overcome the power quality problems caused by nonlinear and reactive loads [9, 14, 23]. These power electronics devices are designed with the goal of obtaining a power factor close to 1 and achieving current harmonics and reactive power compensation [5, 6, 15]. The usual approaches [5, 15] for the control of shunt active filters are based on two hierarchical control loops: an inner one that assures the desired current and an outer one in charge of determining its required shape and the appropriate power balance as well. The control structure followed in this Chapter is the one in [7], in which the current controller is composed of a feedforward action that provides very fast transient response, and also of a feedback loop which includes an odd-harmonic repetitive control that yields closed-loop stability and a very good harmonic correction performance. In turn, the outer control law is based on the appropriated computation of the amplitude of the sinusoidal current network and, aiming at a robustness improvement, this is combined with a feedback control law including an analytically tuned PI controller. However, although the control system performance is very good, it shows a dramatic performance decay when the network frequency value is not accurately known or changes in time. For a better assessment of this issue this Chapter shows the experimental behaviors under constant and varying network frequency. This performance degradation is also presented and analyzed in terms of the THD, PF and cosφ. The Chapter organization is as follows. Section 7.1 introduces the plant, the control objectives and the two hierarchical control loops. Section 7.2 shows the odd harmonic controller designed for constant network frequency, also analysing the performance degradation through the THD, PF and cosφ. Section 7.3 details the results for the varying sampling time repetitive controller including the stability analysis by means of robust control theory. It is worth to say that the stability analysis using the LMI approach introduced in Section 3.3 can not be applied in this implementation since the size of the resulting matrices makes the problem computationally unsolvable. Section 7.4 and Section 7.5 present the implementation of the adaptive pre-compensation scheme and the robust design respectively and, finally, a second order HORC is applied in Section 7.6.

关键词：控制器；并联有源；电力滤波器

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报告从行业事件分析、市场环境、政策环境、分类环境、区域环境、国内对手情报、国外对手动向以及相关行业数据方面对汽车行业进行了分析评论。

关键词：汽车；战略性分析；竞争环境；竞争对手；行业数据

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A novel double-loop control approach for reducing excess torque of the servo loading system based on disturbance observer is proposed.The mathematical model of the loading system is established by mechanism theory and the reasons causing the excess torque are analyzed,the nominal model and disturbance weighting function are determined based on an approximate method.Disturbance observer based the inner loop controller is designed by H∞ mixed sensitivity method and the external-loop controller is designed as the classical PID controller.Both the simulation and experiments results show that disturbance observer is feasible and effective to eliminate the excess torque,accuracy of the loading system is improved.

关键词：控制器；干扰观测器；电动伺服加载系统

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In this paper, the methodology for the design of fuzzy controllers for softcore processors, such as the Xilinx Microblaze embedded in the VIRTEX5 FPGA, is proposed to regulate the angular position of the axes of an experimental platform. The platform uses servomotors to control the rotational movements of the X-Y-Z axes, this with respect to the earth horizon. The angular position is feedback using three inclinometers sensors based on MEMS technology with SPI interface. The desired position is regulated using three independent fuzzy PD+I controllers, which use the error and change of error as input signals. The proposed methodology consists in the design and evaluation of the fuzzy controllers using the Fuzzy Logic Toolbox of Matlab.

关键词：控制器；FPGA；软核；模糊逻辑控制器

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A brushless DC (BLDC) motor achieves higher energy efficiency and endures less wear and tear than a traditional brushed DC motor due to the lack of friction between current coils and motor brushes; it requires additional control logic, however, often implemented using a microcontroller, to perform motor commutation. Standard drive circuitry consists of a rail voltage applied to a three-phase inverter and a pulse width modulated (PWM) signal applied to MOSFET gates in accordance with the commutation pattern. Typically, motor speed control is achieved by varying the pulse width applied to the gates while maintaining a fixed rail voltage. We implemented a proportional-integral (PI) feedback system to control motor speed while varying rail voltage. Using this PI controller, we examined the relationship between steady-state power consumption and rail voltage for a fixed reference, as well as the effect of variable rail voltage on transient controller response and total transient power consumption.

关键词：控制器；无刷直流电机；可变电压轨

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