电机节能控制器的设计

三相交流电动机的负载功率偏低时,电机运行功率因数也较低,适当调节电动机端电压,可以提高功率因数而降低能耗实现节能。本文介绍一种以89C51单片机实现的功率因数控制装置,通过可控硅调压来调节功率因数实现节能,同时该装置还有软启动和多种电机保护功能。实验表明,该装置对经常处于轻载或变负载情况下的电机能取得较好节能效果。     

电机节能控制器的设计

三相交流电动机的负载功率偏低时,电机运行功率因数也较低,适当调节电动机端电压,可以提高功率因数而降低能耗实现节能.本文介绍一种以89C51单片机实现的功率因数控制装置,通过可控硅调压来调节功率因数实现节能,同时该装置还有软启动和多种电机保护功能.实验表明,该装置对经常处于轻载或变负载情况下的电机能取得较好节能效果.     

PIC单片机在电机调压节能中的应用

三相笼型异步电动机的负载率小于６０％时,适当调节电动机端电压,可以降低能耗,实现电机节能。本文介绍了一种以功率因数角和定子电流作为控制参量并用ＰＩＣ单片机实现的可控硅电机调压节能装置。实验及表明,该装置对于经常工作在轻载或变负勒状况下的电机能取得较好的节能效果。     

基于单片机技术的可控硅调压节能装置

介绍了一种以功率因数角和定子电流作为控制参量 ,并用 80 98单片机实现的微电脑可控硅电机调压节能装置。实验及应用表明 ,该装置对于经常工作在轻载或变负载状况下的电机能取得较好的节能效果。     

基于AT89C51的交流电机调速控制系统设计

设计了以AT89C51单片机为核心的价廉、高效的交流电机调速控制系统;对电机的调速方法和控制电路进行了分析和设计,该方法采用先进的过零调功的方式,以功率调节取代常用的电压调节,通过控制可控硅的通断比来调节电动机输出功率,进而达到调速目的.     

异步电动机的节能控制

本文针对当今三相异步电动机浪费相对严重的实际情况 ,从节能角度详尽的分析了其节能的原理。介绍了一种以单片机为控制装置通过控制可控硅调压来调节功率因数的大小 ,进而实现电动机节能目的的节能装置。并且通过实验表明 ,该装置对经常处于轻载和变负载情况下的电动机有较好的节能效果     

基于单片机的步进电机控制系统设计

单片机控制电机具有系统简单,利用率高,性价比高等优点在步进电机控制领域得到广泛的应用。本文正是通过对单片机MSP430控制步进电机研究,来总结使单片机控制的步进电机达到最佳工作状态的方法。     

微电脑控制大型电机启动,节能

介绍了一种采用8031单片机为控制器，结合可控硅的过零控制方式，实现对大型电机的启动、节能控制。     

基于AT89C52的风扇温控调速器的设计

设计了一个基于单片机AT89C52的电风扇温控调速器.单片机读取温度传感器DS18820测量的温度信息后,通过设定的算法,控制双向可控硅的触发角,进而通过调节电风扇的有效电压值来调节电风扇转速.同时.人体红外模块通过检测一定范围内是否有人存在来自动控制电风扇的转动和停止.     

氩离子激光器单片机控制系统的研制

介绍腔外棱镜选频大功率氢离子激光器的自动控制系统的研制。步进电机通过机械传动机构调节选频棱镜的角度实现输出光波长的转换;通过调节激光器工作电流实现输出光功率控制。在单片机控制下,利用位置敏感器件（PSD）及光功率采样装置提供的信号,实现了棱镜最佳位置的自动技柬与光功率的反馈调节。实际运行表明,该系统调整速度快、运行安全可靠,真正实现了氩离子激光器自动调节。     

桥门式起重机最优调压节能仿真研究

为了实现起重机最优调压节能运行,针对起重机的恒转矩运行和变工况负载特性,基于异步电动机Γ型等效电路,将定子铜耗和铁耗看作是仅与定子电压有关的不变损耗,将转子铜耗看作是随负载转矩变化的可变损耗,得到电气总损耗与定子电压和负载转矩的直接关系。通过求解得出电动机稳定运行条件下使电气总损耗最小的最优电压。研究和仿真结果表明:定子电压和负载转矩共同影响总损耗,按照电动机稳定运行时的近似转差率得出总损耗的精确解和近似解在低于200V时,误差较大,在高于200V时误差几乎为零,而随负载转矩变化的最优电压误差不超过7V;起重机按照负载转矩变化的适时调压运行方式的节能效果是显著的。     

基于单片机异步电动机节能装置的研制

由异步电动机的Γ型等效电路 ,得出为使其损耗最小就应使电源电压随负载的变化而变化并保持Mem/U21为常数 (等于额定转差率sN)。根据这一结论 ,应用单片微机控制双向可控硅的导通角 ,设计出一种节能装置 ,并给出该装置节电率随负载变化的曲线 ,效果较为满意     

一种基于射极输出器关断的声光控LED照明灯

声光控开关的主电流回路一般用可控硅控制.220 V市电输出端串接普通白炽灯;交流电源经过桥式整流后输出的脉动交流开关接可控硅阳极,控制白炽灯的亮与暗.用基于射极输出器关断的声光控开关,控制LED照明灯工作,用于没有220 V市电电网的特殊公共场所的照明.照明方法简便,方便人们生活.     

面向DO-178C的襟缝翼控制系统需求的形式化描述

DO-178C是对机载软件适航认证标准DO-178B的改进和补充,用于对民用飞机机载系统和设备软件质量控制提供指导。SCR(Software Cost Reduction)方法作为一种形式化方法,基于四变量模型,可以对复杂和大型的嵌入式系统进行需求描述。文中基于DO-178C,使用SCR方法对原飞机系统中的襟缝翼控制系统的需求文档进行形式化的需求描述,针对襟缝翼控制系统中的襟翼电机转速控制模块进行详细的案例分析,判断其是否满足DO-178C的相关验证指标。通过分析和验证,提出了SCR方法中的一些应用技巧。该工作可为SCR方法在机载软件系统中的应用提供依据。     

On efficient variable voltage linear power supplies

The computer aided design of variable voltage, single-phase, linear power supplies using an SCR bridge is discussed. The effects of transformer leakage reactance, resistance, filter capacitance, the low power integrated circuit voltage regulator and the current boost circuit used to increase output power from such supplies is taken into account in the design. By controlling the firing angle of the SCR bridge, the resultant linear supply is more energy efficient in power conversion than the traditional diode bridge based linear power supply. The increase in amplitude of the low frequency harmonics in the line current of the SCR bridge based supply is quantified vis-á-vis the diode bridge based supply. A prototype SCR bridge based design is used to experimentally validate the design computations. An implementation of a controller to operate the SCR bridge based supply efficiently is discussed.     

基于六脉波交交变频的分频启动方法研究

在分析六脉波交交变频的基础上及根据软启动中的电压双斜坡启动原理,提出了一种基于六脉波交交变频的分频启动方法。该方法根据交交变频原理和晶闸管触发规律,在电动机启动时,直接在电动机定子侧加电动机启动所需最小转矩所对应的电压值,然后逐级增加变频输出电压值,直至最终所需电压。仿真结果表明,通过合理选择变频输出电压的大小,调节每个等级电压作用的时间,能够有效控制电动机分频启动过程中定子电流的大小,获得良好的转矩变化曲线,改善电动机启动性能。     

An ultra-high-speed motor driver with hybrid modulations

An ultra-high-speed motor driver with hybrid modulations is proposed in this paper. The speed range of a spindle motor is wider and trends to ultra-high, but the traditional driver which provides either sinusoidal pulse width modulation or six-step modulation could not support so wide speed range. Normally, the variable voltage variable frequency control is used to support different type motors, then, sinusoidal pulse width modulation (SPWM) is chosen in low speed range drivers and six-step is picked in high-speed application. In this paper, the hybrid modulation driver with adjustable DC bus voltage is proposed, and the modulation could be selected for different motor and speed by users. For lower switching power loss, the six-step modulation is better when ultra-high-speed application. For low speed range, the trapezoidal pulse width modulation is used to replace the SPWM for the reduction of switching power loss. The experimental results show the performance of proposed driver.     

Vector control for loss minimization of induction motor using GA–PSO

This paper deals with the GA–PSO (genetic algorithm–particle swarm optimization) based vector control for loss minimization operation of induction motor. It is estimated that more than around 50% of the world electric energy generated is consumed by electric machines such as induction motor, dc motor. So, improving efficiency in electric drives is important and control strategy for minimum energy loss is needed as one of optimal operation strategies. The vector control of induction motor has been widely used to operate in a wide speed range by using flux weakening at rated speed. However, it is still necessary to advance because of coupling is behavior between fluxes in motor. In this paper, vector control approach is suggested for an optimal operation of induction motor using variable acceleration and GA–PSO tuning method through simulation. We can obtain satisfactory results for energy saving control.     

Survivability-oriented optimal node density for randomly deployed wireless sensor networks

The survivability is usually critical for wireless sensor networks,which are often deployed in the unattended harsh environment.Lots of technical schemes to improve the survivability depend on the redundant resources of the sensor networks.The amount of resources is usually determined by the node density during the deployment phase.For the random deployment and random node failures,the quantitative relation between the survivability and the node density is studied.Based on the conditional survivability,the node density to meet the required survivability level is presented.Finally,the survivability for unpredictable failures and the optimal node density to maximize the price–performance ratio are also discussed.     

基于LPC2138的异步电动机变频调速系统

本文设计研制了一种以LPC2138高性能ARM7处理器作为主控器,采用SPWM算法和恒压频比控制策略的新型异步电动机变频调速系统.该系统具有处理速度快、控制精度高、结构简单、工作稳定的优点,可实现异步电动机的平滑调速,同时器件开关损耗小,适用于普通工业电机控制场合.