工程型变频器机械制动控制功能应用研究

本文简要介绍了通用变频器和工程型变频器的机械制动控制思想方法以及在负载启动停止时两种机械制动的工作过程,分析了工程型变频器机械制动功能的优点,并结合西门子6SE70变频器机械制动功能在济钢副枪起升机构中的应用,给出一个典型的工程型变频器机械制动控制的实例,可为国内位能型负载机械制动控制功能的设计、应用提供参考。     

变频调速器在单沟提升机中的应用

本文介绍了单沟提升机变频器的工作原理，阐述了该类变频器制作上的难点，指出了回馈制动在变频器制作上的重要意义。通过现场应用，展示了提升机变频器广阔的应用前景。     

抽油机变频器的改进

本文介绍了回馈制动在抽油机变频器上的应用,与传统的能耗制动进行了比较,指出了该类变频器制作的关键点,分析了在节能方面的优势。     

变频器在离心机中的应用

本文主要讲述康沃变频器在工业离心机上的应用及变频器制动单元在该设备上的使用。     

变频器在起重设备上的应用

介绍了ATV58变频器软件设计上内置的一些特殊功能，如制动逻辑顺序控制，低频大力矩等，这是起重行业所必需的，同时应用这些特殊功能设计了在葫芦吊和自行车上的应用。     

变频器的综合应用（六） 第6讲 变频调速系统的制动设计

1引言 在本节中，主要阐述的是变频器的制动设计，阐述了能耗制动、回馈到共用直流母线方式的制动、回馈到交流电网的制动共3种典型制动方式的工作原理，以及应用范围和优缺点。     

变频器在龙门刨床改铣床中的应用

龙门刨床用艾默生变频器改造成铣床，提高生产效率．用RS-485通信，控制四台变频器调速和启停，控制线路简单。     

变频器在印染设备多电机同步调速中的应用

本文概述了变频器在印染设备多电机同步调速中的应用，从通用变频器到伺服变频器，包括有松紧架和无松紧以及卷绕驱动。     

变频器的选型及配置要点

本文针对应用广泛的通用变频器，提出了在变频器选型和外围配置中需要注意的一些问题。     

数字正交上变频器AD9857

AD9857是AD公司生产的一种高性能通用数字正交上变频器，它在内部集成有高速直接数字频率合成器，14位数模转换器，信频电路，数字滤波器以及其它的数字信号处理功以,用于通用I／Q调制器，变频器，单频率DDS等系统中，文中介绍了它的基本原理与使用方法，给出了它在数字电视系统中的一种应用。     

基于单电源IPM模块的变频调速控制器系统综述

本文阐述了U／F控制变频调速的基本原理，分析了变频调速控制器的典型拓扑，进而对采用隔离方案和共地方案设计的变频调速控制器系统进行了介绍。尤其对采用单电源智能功率模块实现共地系统设计进行了详细的阐述，并给出了两者之间设计上的差异和共地系统具有的成本优势，最后对采用单电源智能功率模块实现共地系统的应用给予了展望。     

Comparison of energy-saving on the speed control of the VVVF hydraulic elevator with and without the pressure accumulator

The speed control system of variable voltage variable frequency (VVVF) hydraulic elevator with the pressure accumulator has been designed, which is a kind of the innovation energy-saving hydraulic elevator. The control system of the VVVF hydraulic elevator with the pressure accumulator is analyzed, and the speed control of the VVVF hydraulic elevator with the pressure accumulator is studied using the PID control algorithm. The comparison of the experimental researches of energy-saving is carried out for the speed control of the VVVF hydraulic elevator with and without the pressure accumulator. The experimental results show that the VVVF hydraulic elevator with the pressure accumulator has higher efficiency compared with the VVVF hydraulic elevator without the pressure accumulator.     

Priority shaping of traffic streams sharing a policed virtual path in an ATM network

Traffic streams with differing service requirements, sharing a single contract for use of a policed virtual path in an ATM network, may be jointly shaped to make the best use of bandwidth available in the path. The shaper may use the information about the network policer to perform self-policing with a form of priority service to ensure satisfactory levels of cell loss and delay for both real-time and non-real-time traffic. Two such shapers are considered assuming a mean bit-rate contract with the network in which a leaky-bucket mechanism performs the policing function. The performance of the shapers is analysed using Markov-modulated models of bursty traffic sources and stochastic fluid methods, and the analytical results are corroborated by simulations. The choice of the shaper type and optimization of the shaper design parameters are discussed using correlated and non-correlated source models.     

Creation of a stable and convex static meniscus,which is appropriate for the growth of a single crystal ribbon with specified half thickness

A stable and convex static meniscus is appropriate for the growth of a single crystal ribbon of given half thickness, if the upper half thickness of the meniscus is equal to the ribbon half thickness and the angle between the tangent line to the meniscus and the vertical is equal to the growth angle. In this paper the material parameters, the shaper half thickness, the gas pressure above the meniscus and the half thickness of the ribbon, which has to be grown, are considered prior given. The problem that is solved is the determination of the melt column height (between the horizontal crucible melt level and the shaper top level) such that the resulting meniscus is convex, is static stable and is appropriate for the growth of the desired ribbon. The determination is numerically illustrated for silicon sheet and the dependence of the melt column height on the shaper half thickness is discussed.     

Two-wheeler magnetorheological drum brake operating under hybrid mode for enhancing braking torque: Development and validation

In the present work, a new design of magnetorheological (MR) drum brake for two-wheeler is presented, which can be operated in hybrid mode i.e. compression and shear modes, unlike the conventional one, which only operates in single mode. For compressing the MR fluid zone, a spring-cam-lever mechanism is used. The braking torque of the proposed drum brake in compression and shear mode is analytically derived. The brake performance of the fabricated drum brake is studied experimentally and analytically at different speeds and those braking torque results have been compared. A magnetic field simulation is performed on COMSOL Multiphysics 5.3a in order to get a suitable operating current for the designed MR brake. The torque behaviour of the designed brake is compared with that of a conventional friction drum brake. It is found that brake performance improves with mixed mode compared to single mode and it also depends on the speed of the rotor.     

阿钢炼钢厂电炉除尘风机变频调速装置的应用

本文结合电炉除尘工艺,介绍了阿钢电炉除尘风机变频调速系统控制方案,在冶金行业除尘风机上应用高压变频调速系统的节电效果是非常显著的。     

基于光纤环形镜的全光脉冲整形器

提出了一种基于光纤环形镜的全光脉冲整形器。该全光脉冲整形器利用波分复用器将控制光脉冲引入光纤环形镜中，控制光脉冲由于交叉相位调制在信号光上产生了非线性附加相移。信号光在耦合器中发生干涉，经过整形的信号光脉冲从脉冲整形器的出射端出射，信号脉冲的波形由非线性附加相移的波形决定。实验中．利用对控制脉冲光谱整形和啁啾展宽的方法来对控制脉冲进行时间脉冲的整形，该全光脉冲整形器实现了对单纵模激光的脉冲整形，同时实现了飞秒脉冲和单纵模整形脉冲的精确同步。在理论上数值计算了该全光脉冲整形器的输出特性，理论计算结果和实验结果相一致，并为“快点火”实验提供了一条可行的技术途径。     

现代变压变频（VVVF）驱动装置

本文以异步电动机和永磁同步电动机的同步速度产生原理及控制要求为基础，探讨了一般驱动装置的结构、优点／缺点、控制性能、选用、各种驱动装置的能耗以及正确安装方法，说明了变频装置与矢量控制装置的异同，并对其可靠性进行了研究，提出了变压变频驱动装置的发展趋势。     

DESIGN AND EVALUATION OF GCRA SHAPER AND ENFORCER ARCHITECTURE IN ATM NETWORKS

The leaky bucket scheme has been widely treated as a traffic control mechanism. The corresponding multi-connection shaper, which intends to make the passing traffic comply with the declared parameters in the enforcer, has also been implemented. However, we must point out that the regulated cells may be invalid at the corresponding enforcer, even if the CDV between the shaper and enforcer is neglected. In order to cope with this problem, two enforcing methods, say ALP_LB and GCRA, are tried and evaluated. We modify the GCRA algorithm, which was suggested by ITU-T recommendation I.371 and even extended by ATM Forum ’93, to be suitable for shaping. The shaper and enforcer architecture which is suitable for both ALP_LB and GCRA methods is proposed. Simulation results verify the shaping and UPC functions of GCRA. They also reveal that the GCRA shaper would not introduce long delay and queue length. The proposed shaper architecture does have some merits compared with others. Such a shaper is also suitable for regulating traffic for NPC (network parameter control) at the NNI (network node interface).