可编程序控制器逻辑程序设计方法综述

在电气控制领域中，可编程序控制器（ＰＣ）已成为一种不可替代的核心控制器件。针对其逻辑程序设计，概述了数种软件设计方法。这些方法对更好地设计复杂的ＰＣ应用逻辑程序有一定的指导意义。     

A graphical tuning method of fractional order proportional integral derivative controllers for interval fractional order plant

In this paper, a novel graphical tuning method of fractional order proportional integral derivative (FOPID) controllers is proposed for a given interval fractional order plant family. Firstly, an approach is presented to solve the problem of robustly stabilizing the interval fractional order plant using FOPID controller. Moreover, some alternative methods are developed to reduce the computational burden of the presented approach. The results obtained here are general and strict proofs are given on these results. Secondly, a new approach is presented to calculate the complete sets of FOPID controller parameters which guarantee the specified H_∞-norm constraint for the interval fractional order plant. The developed approach is convenient and flexible. Finally, a unified design framework is proposed. The aim of the unified design is to compute the biggest region which can simultaneously provide internal stability, maintain the classical gain and phase margin and guarantee the modern H_∞-norm constraint for the interval fractional order plant. Examples are followed to illustrate the design procedure.     

Megastability in a quasi-periodically forced system exhibiting multistability,quasi-periodic behaviour,and its analogue circuit simulation

In this paper, we present a new quasi-periodically forced system which exhibits coexistence of an infinite number of nested attractors (megastability) along with quasi-periodic and multistable behaviours. The dynamical behaviour of the system is analysed using the Lyapunov exponents, Lyapunov spectrum, bifurcation diagrams, and phase plots. An analogue circuit of the proposed system is designed and simulated using the NI Multisim simulation environment to access the unusual dynamical behaviour of the proposed system.     

副井操车联动闭锁系统的设计

设计了一种以RS扭环步进器为核心部件的井口操车联动闭锁控制系统,实现摇台、安全门和推车机等执行设备的联动控制和罐挡的自动控制。     

Low power, GHz class ADC for broadband applications

The design of ultra-low power (<100 mW), high-speed analogue to digital converter (ADC) is an essential element for the next generation radio telescope, the square kilometre array (SKA). CMOS technology is limited in high precision applications, such as ADCs due to the stringent requirement of device matching. Also to achieve high-speed (f_t>100 GHz) CMOS requires deep sub-micron gates (90 nm or less) where expensive phase shift masks are required. This paper describes the design and simulation of a low-power high-speed (4 GS/s) analogue to digital converter based on an InP/InGaAs heterojunction bipolar transistor (HBT). The technology used was developed at the University of Manchester using MBE growth which relied upon two novel developments. Firstly stoichiometric conditions permitted growth at a fairly low temperature of 420 °C while conserving extremely high-quality materials. Secondly dimeric phosphorus was generated from a gallium phosphide (GaP) decomposition source leading to excellent RF device properties. The DC and RF performance of the fabricated HBTs showed characteristics ideally suited to low-power IC designs, with current gain 70, low offset voltages and achieving an f_t=91 GHz and f_max=83 GHz on a 1.5×5 μm² emitter area device using fairly relaxed optical lithography.     

Control of distributed generation

Summary  Distributed generation (DG), whose installed capacity is increasing rapidly, can be defined as low rating generation that is neither planned nor dispatched centrally and is usually connected to the distribution network. Appropriate control of DG can improve the performance of DG units without violating network constraints, and facilitate the effective participation of DG in power system and market operation. Two control levels, DG unit control and network control, are summarized. DG unit control is introduced based on three technologies: induction generators, synchronous generators and power electric converters. Effective network control can be built based upon active management concept. Finally, three DG control paradigms, MicroGrid, cell and virtual power plant, are discussed.      

A high-linear wide-tunable CMOS transconductor for video frequency applications

In this paper a new CMOS transconductor structure based on a g_m-boosted degenerated differential pair is presented for applications in the video frequency range. The proposed circuit combines two techniques, a switchable array of source degenerating MOS resistors and a programmable output current mirror, in order to widen the G_m tuning range while maintaining linearity. Degeneration MOS resistors are made common-mode voltage independent thanks to a simple control circuit. Post-layout simulation results from a 0.35 μm design supplied at 3.3 V show a wide tuning range (10–100 MHz), good linearity (−58.4 dB for an output signal voltage of 1.1 V_p–p) and low excess phase (<0.5° over the whole tuning range).     

红外线气体分析记录仪模拟校准及检定方法

叙述了模拟校准红外线气体分析记录仪标尺刻度的工作原理，介绍了模拟校准该仪器标尺刻度的方法及其改进的检定方法，提出了该仪器的测量准确度，减少其示值误差和测量不确定度。     

Experimental analysis of battery charge regulation in photovoltaic systems

The influence of charge regulation on batteries for stand‐alone photovoltaic systems is analysed in relation to two factors: battery lifetime and the daily energy service supplied. The regulation thresholds adjusted in the charge controller (for disconnection and reconnection), in overcharge and deep discharge conditions, determine the whole system operation. Laboratory testing procedures are proposed and applied to different components of the photovoltaic rural electrification market. Finally, technical recommendations for charge regulation of lead–acid batteries are presented. Copyright © 2003 John Wiley & Sons, Ltd.     

继旧开新——城市住宅设计

在阿尔多·罗西短暂的瑞士教学后,他的学生们对其思想和设计方法论进行了演绎发展.其中法比奥·莱茵哈特和米洛斯拉夫·锡克从20世纪80年代起所创立的“类比建筑”(Analoge Architektur)教学与实践方法论最为系统化.本文是锡克基于他过去四十年教学与实践,对欧洲城市住宅的类型研究与设计思考.对罗西和他所影响的瑞...