电动机

A control system of stepmotor that enable operator to control displacement and adjust velocity discretionarily was designed, using the TMS320LF2407 chip and the step motor drive. This control system can control step motors.

论文从工程应用的角度出发，以TMS320LF2407A DSP芯片作为控制核心，结合专用步进电动机驱动器，设计了一套可控制的电动机，且具有位移控制和多级调速功能的步进电动机控制系统。

In the performance of electric control system,it is an important mean to use low voltage motor protector for protecting and monitoring electromotor in power plant.

1引言随着电动机控制中心技术的发展，模块化的智能电动机保护器得到了越来越广泛的应用，同时也对电动机保护提出了更高的要求。

The Series are the newly products with premium efficiency, The whole range motors efficiency are designed and manufactured according to America NEMA Premium Efficiency Standard, The efficiency is much higher tnan of NEMA Standard Epact high-efficiency motors.

NEP系列高效率三相异步电动机是全新设计的超高效率电动机，整个系列的效率是按美国NEMA超高效率标准进行设计的，整个系列的电动机效率高于NEMA标准的Epact高效电机的效率。

It is presented that the design features of terminal box for Series YBK2 flameproof three-phase induction motor,comparing with Series YBK and a design proposal is given in this article.

文章对YBK系列电动机和YBK2系列电动机接线盒的规格进行了比较，介绍了YBK2系列电动机接线盒的设计特点，最后给出设计方案。

In last several years, there have been numerous publications on sensorless operation, but most of these techniques only rely on the fundamental machine equations, which limits the low speed and zero speed operation of the machine, and are sensitive to the machine parameters.

目前，永磁同步电动机无位置传感器控制技术的研究已经取得了丰硕的成果，但大多依赖于对电动机基波方程的分析，不适于低速及零速下应用，而且对电动机的参数非常敏感。

Pole and slot and indicates the rule followed, depending on the structure features and performance characteristic of DC motor, and design 240w brush less DC motor based on armature reaction, and analyzes detailed Hoer position sensor and the control and drive of rush less DC motor.

而且针对直流电动机结构特点和工作性能，在电枢反应理论基础上设计出功率为240w的无刷直流电动机，并对霍尔位置传感器和无刷电动机的控制及驱动做了详细的分析。

As the main conversional device of mechanical energy to electrical energy, the motor has mainly three types, such as,the DC motor, the synchronous motor, the asynchronous motor .

电动机作为机电能量转换的主要装置，其主要类型有直流电动机、异步电动机和同步电动机三种。

The engine main circuit have to be gurranteed drawing the torque of electric motor and rotation speed wholly to do regulateing of independence ,But also possess extensive setting range SS7's mould electric locomotive adopts Quan Kongqiao and semi bridge accuseeing series connection to make up the monophase bridge style commutation electric circuit ,The coil power supply is encouraged against the stringtrain by the electric motor the drawing armature to 3 parallels operation ,Still there is an excitation commutation bridge ,He encourages the coil power supply with 3 electric motors drawing together to the series connection ,Moreover has one another accuses the regulating action .

机车主电路必须保证牵引电动机的转矩和转速都可作独立的调节，而且要有宽广的调节范围。SS7型电力机车采用一个全控桥和一个半控桥串联组成单相桥式整流电路，向3台并联工作的牵引电动机电枢与串励绕组供电，还有一个励磁整流桥，向串联在一起的3台牵引电动机他励绕组供电，并具有相控调节作用。可以实现机车无级调速和无级削磁。SS7型电力机车采用再生制动方式，再生制动时，牵引电动机作直流发电机工作，并且将电能馈送回接触网，此时电力机车相当于一个移动的发电站。

That is to say, during the starting process of induction motor, hold-off angle of current has gradually decreased from initial value to zero. The method can always make the displacement angle less than thyristor's firing angle. So the voltage of the induction motor won't oscillate. Therefore, the oscillation of current, electromagnetic and speed can be eliminated during the soft-starting process of induction motor. This paper verifies the correctness of the method by simulation at first.

根据上述原因，本文提出了采用关断角控制的新型控制策略，这种控制策略是使电动机在起动过程中的电流关断角由某一初始值逐渐减小到零，利用该方法可以使感应电动机起动过程中的续流角始终小于晶闸管的触发角，这样续流角的变化就不会引起电动机端电压的振荡，因而就从根本上消除了感应电动机软起动过程中的振荡现象。

The following functions can be realized: Measuerment:the effective values of three phase current and voltage, power frequency, active power, reactive power, power factor etc. Motor control: direct starting, converse starting, star and triangle starting, self-starting. Protection:thermal overload protection, current leakage protection, open-phase protection, three-phase unbalance protection, over voltage protection, loss voltage protection, low load protection and fault warning and fault dates memory. Communication: communication of the computer in control room and the microcomputer monitor in the spots is realized by the interface of RS-485. The motor is not only controlled in the spots but also in control room. The dates, information and some functions are shared by the spots and control room too.

该电动机监控器以80C196KC单片机为核心，通过采样三相电流﹑电压信号来实现以下功能：三相电流﹑电压有效值，电网频率，有功功率，无功功率及功率因数等的测量；对电动机实现直接、正反转、星三角及自起动控制；对电动机实现热过载、漏电、断相、三相不平衡、过压、欠压及轻载保护，对故障进行报警及数据记忆；通过RS-485串行接口与中央控制室计算机实现通信功能，对电动机既可本地，也可远程控制；实现控制现场与控制室之间数据、信息、功能共享。

I am accused of being overreligious," she said in her quiet, frank manner,"but that does not prevent me thinking the children very cruel who obstinately commit such suicide.""

客人们在卡罗利娜·埃凯家里，举止就文雅一些，因为卡罗利娜的母亲治家很严厉。

Designed by French fashion house Herm è s, this elegant uniform was manufactured in our home, Hong Kong, and was the first without a hat.

由著名品牌 Herm è s 设计，这件高贵的制服是香港本土制造，是我们第一套不配帽子的制服。