基于GAL的五相步进电机驱动器

介绍了一种五相混合式步进电机驱动方法,及五边形绕组联接方式。用GAL器件产生脉冲分配信号。步进电机采用恒频斩波、恒总电流驱动,电路性能可靠、简单。     

Playful reflection: an investigation into the kindergarten project ‘Play in physiotherapy with children’

This article investigates adult learning in an action research (AR) project called ‘Play in physiotherapy with children’, conducted in Tromsoe Municipality, Norway, in 2010–2011. The project's objective was to explore how a play-based intervention approach would affect professional collaboration and child development. It was designed as a small-scale project, organized around two children with motor delay and their professional teams of teachers, physiotherapists and special pedagogue in two different kindergartens. It was situated in the kindergartens, and lasted for 16 weeks. The professional participants were invited into a process of action–reflection cycles as co-researchers. Video was a core tool in the design. Treatment sessions with the children were filmed during the action phases, and were the focus of attention in the reflection meetings. The two professional teams evaluated the video-reflection meetings as crucial to their learning and change. The focus in the article is on the learning in the reflection meetings during the AR process. We discuss two aspects of the space of reflection that was created during the project. First, we look into the role of video in reflection, and discuss how this can be understood with the help of concepts from Bourdieu's ‘theory of practice’. Second, we reflect on the role of play and playfulness in reflection and change among grown-ups. To do this, we use perspectives from phenomenological theory on play and playfulness from Buytendijk and Gadamer. We conclude that the use of video-reflection is a potent tool in AR processes. Concepts from Bourdieu's ‘theory of practice’ illuminate why, and also contribute to the understanding of the experienced change. Further, we argue that theory on play can help AR practitioners to understand the mechanisms of engagement and involvement that are crucial in AR processes.     

两相步进电机的双极细分驱动及Proteus仿真

从软件仿真的角度,论述了两相步进电机的双极细分驱动原理,给出了细分驱动的波形、C语言编程方法及其Protues仿真结果。     

浅谈电气口诀在实际项目中的应用

本文主要介绍了用电气口诀估算交流电机的用电容量,阐述了估算公式的来源。以＂监控组态技术在大型广告屏上的应用＂项目为例,指出了实践经验与理论知识相结合,能够方便、快速、准确地对交流电机控制系统进行设计、安装、运行和维护。     

电动机正反转Y-△起动程序设计与仿真

这是一个用可编程控制器（PLC）来控制三相交流异步电动机进行正反转Y-△降压起动的教学实例。从控制要求出发,详细地介绍了I/O分配接线图、电动机主电路图、PLC程序设计的原理及梯形图逻辑测试等内容。通过这个教学实例,学生不仅能了解到怎样用PLC程序来满足用户所提出的控制要求,还能自己动手用仿真软件所具有的梯形图逻辑测试功能来对自己所设计的程序进行梯形图逻辑测试（仿真）。在通过了测试以后,学生还能根据I/O分配接线图和电动机主电路图,练习实际的接线和调试。     

基于DSP56F805的数字多联变频空调控制系统设计

研究了以DSP56F805控制芯片为核心的数字多联变频空调控制系统,并详细阐述了各个主要电路的组成与作用,最后对系统软件设计进行了说明.     

基于PLC的步进电动机控制系统研究

依据步进电动机的工作原理以及控制方法,提出了步进电动机控制系统的设计方案。使用西门子CPU224可编程控制器作为核心控制器设计出步进电动机控制系统,可以实现对三相步进电动机速度、正反转、三相单三拍、三相六拍等多种运方式的控制。给出控制系统软硬件的实现方法,整个控制系统结构简单,功能较强,可靠性高。     

步进电机的单片机驱动控制

以步进电机作为动力装置,介绍了系统的组成.采用STC89C52作为主控制芯片,红外避障传感器型号为E18-D80NK,黑白线检测传感器型号为TK-20,步进电机型号为SST42D1070,通过红外避障传感器和黑白线检测传感器的协同工作,将采集得到的数据经主控制芯片分析处理后对步进电机做出指示,并将小车的行程和速度通过1...