基于ACS712的直流电机电流监测系统的设计

设计了直流电机运行电流的硬件采集电路,解决了高速下电枢绕组电流的采集问题。利用霍尔电流传感器ACS712通过AD转换将采集到的绕组电流数据,通过串口和上位机进行通信,实现了本机LCD液晶显示和基于LabVIEW的软件界面显示电流数据,具有实际的工程意义。     

汽车空调风门耐久试验装置设计

设计一种用于空调风门耐久试验的装置,该装置使用STM32F103RCT6微控制器作为系统控制核心,包含ACS712电流传感器采集电路及全桥驱动电路模块RZ7899。采集电路采集与风门执行电机相连的实时电流,输出电压确定风门的位置情况,反馈控制系统,由驱动电路模块实现风门任意位置的启停,避免耐久试验过程中因风门故障被卡住,电流突然增加而损坏电机的危险;采用电驱RZ7899,基于H桥控制原理,实现电机正反转的功能。     

基于C8051F380单片机的数据采集控制器设计

在广播发射台站管理与监控系统中,很多广播发射机都无远程监控接口。设计了一种基于C8051F380单片机的数据采集控制器,对无远程监控接口的发射机进行加装后,实现了发射机的多个运行参数的数据采集和控制,通过串口按所定义的通信协议同数据采集控制器进行通信,并可以通过LCD进行同步数据显示。     

LMV651提高系统设计的质量与效率

以便携式电子产品为例,系统设计工程师要面对成本压力,因为产品价格必须尽量降低,才可凭借价格优势,抢占更大的市场。放大器是这类便携式系统的重要组成部分,因为这类器件可以执行信号放大、滤波、转换及其他功能。     

Effect of laser induced rapid solidification structures on adhesion and bonding characteristics of alumina/silica based oxide to vitreous enamel

Abstract

The present work is concerned with investigating the effects of high power diode laser (HPDL) radiation on the microstructure of an amalgamated alumina/silica based oxide compound (AOC). The main rapid solidification theories, namely constitutional supercooling and the theory of morphological stability, are used to explain the observed microstructural changes in the AOC resulting from HPDL interaction. Without laser treatment of the AOC surface it was impossible to fire the enamel onto the AOC. However, wetting experiments, using a number of control liquids and the sessile drop technique, revealed that laser treatment of the AOC surface significantly altered the wetting characteristics of the AOC and allowed the enamel to bond to the AOC. Accordingly, HPDL treatment was identified as allowing the vitreous enamel to wet the surface by causing a decrease in the enamel contact angle from 118° to 33°. Moreover, no discernible difference was seen in the change in contact angle across the range of rapid solidification microstructures obtained. The actual incidence of rapid surface resolidification, and not the degree of rapid surface resolidification, was therefore identified as being the primary factor governing changes in contact angle. The bonding mechanisms were identified as being principally owing to van der Waals forces, however, some evidence of chemical bonding was also observed. The work has clearly shown that laser radiation can be used to alter the wetting characteristics of the AOC.     

APPLICATION OF EXTENDED EVOLUTIONARY PROGRAMMING TO SVC PLACEMENT

An extended evolutionary programming (EXEP) technique is proposed for optimal solution of the SVC placement in voltage stability enhancement. Multiple genetic transformation operators are used to ensure that the global optimal solution can be obtained. The problem is posed as the minimization of the function whose objectives are to increase the reactive power margin, the reactive power spinning reserve and the system voltage profile. At the same time it is required that the transmission losses are reduced and the additional cost of new SVC devices is minimal. All the operational inequality constraints are transformed to the objective function by using quadratic and cosine penalty functions. Numerical results show that EXEP technique is superior to simulated annealing(SA) technique.     

基于SVME/DMV-712的Vxworks系统下图形用户界面开发

当前，图形用户界面已成为人机界面研究的一个重要方面，在Vxworks操作系统下进行应用软件开发．通常也要进行图形和界面设计。X-Windows／Motif是一个符合国际开放标准且应用非常广泛的图形开发环境，在其环境下实现应用程序人-机界面的设计在国内已日趋重要。本文通过对基于SVME／DMV-712的Vxworks系统下图形界面开发技术的研究，提出了图形用户界面的层次结构，在此基础上又总结出Vxworks平台下基于X接口．Motif接口和Motif与OpenGL混合编程的三种图形用户界面开发模式．并给出了基本的实现步骤。     

基于涓电流检测的节能插座设计

为了能够在电器设备关机或待机情况下有效切断外设电源,达到节能的目的,以低功耗STC89C52RC微控制器作为控制电路的核心,通过检测回路的涓电流以及红外遥控信号,设计了一种节能插座,实现对电器电源的智能控制.本节能插座使用方便有效,实现了外设的零待机功耗,顺应了节能减排的时代潮流.     

齿轮钢20CrMnTi水口堵塞原因分析与改进

通过对齿轮钢熔炼成分及生产工艺流程的介绍,阐述了水口堵塞对齿轮钢生产带来的主要危害。针对齿轮钢水口堵塞的原因及改进措施进行了分析研究,重点对钢水处理时钙的加入量进行了理论计算与分析。