电动机

A design of controller using TIMSP430F149 for three-position isolation switch is presented.

在中高压电力系统中，由于三工位隔离开关的操作力矩较大，为了实现由外部保护装置控制，必须采用电动机操纵。

The article presents the developing condition of PWM and SVPWM first.Then the theory of SVPWM is discussed in detail.The SVPWM is based on the thought of magnetic chain tracking.It makes the ideal magnetic chain circle of three-phased sysmmetry electric motor supplied by three-phased sysmmetry sine wave voltage for basis,uses the practical magnetic chain vector formed by the different switch modes of three-phased inverter to track the basic magnetic chain circle.During the course of tracking,the inverter changes the switch modes properly to form the PWM waves.Then the modulation wave of SVPWM is analyzed in detail.The modulation wave of SVPWM is implicit,but the analogous modulation wave in A-B-C axis needs to be calculated in order to expose the internal relation of SVPWM and SPWM.That is to show the implicit modulation wave of SVPWM. SVPWM actually is a transformed SPWM ruly sampled by the modulation wave which is injected by the zero prefaces based on space vectors.

本文首先对脉宽调制技术的发展现状进行了综述，在此基础上分析了电压空间矢量脉宽调制技术的发展现状；接着对空间电压矢量脉宽调制技术的基本原理进行了详细的分析和推导，SVPWM是基于磁链追踪的思想，它以三相对称正弦波电压供电下三相对称电动机定子理想磁链圆为基准，由三相逆变器不同开关模式下所形成的实际磁链矢量来追踪基准磁链圆的，在追踪的过程中，逆变器的开关模式作适当的切换，从而形成PWM波；然后详细分析了电压空间矢量脉宽调制技术的调制波，虽然SVPWM法的调制波是隐含的，但是为了揭示SVPWM法与SPWM法的内在联系，需要求出SVPWM在A-B-C坐标系上的等效调制波，也就是将SVPWM的隐含调制波显化；SVPWM实质是一种基于空间矢量在三相正弦波中注入了零序分量的调制波进行规则采样的一种变形SPWM。

Hangzhou Electric Co., Ltd. is a±has more than thirty-year history after a restructuring of private enterprises, professional production of small and medium-sized motors.

杭州江潮电机有限公司是一家有三十余年历史经过改制的民营企业，专业生产中小型电动机。

Using a drum Cr18Ni9Ti furnace tank made of stainless steel cylinder, or a Cr-Mn nitrogen heat-resistant steel castings, by the end of the furnace body, bearing bearing supports, and with a motor-reducer for use furnace tank to the slow rotation, with drum parts Rotation of the tank furnace heated evenly, and the workpiece between each other without coverage phenomenon, the same color after heat treatment furnace can feed the other end to the mouth from two roller bearing.

滚筒炉罐采用1Cr18Ni9Ti不锈钢制成圆柱型，或采用铬锰氮耐热钢铸件，一端由轴承支座在炉体外支承，并采用电动机带减速机进行传用，使炉罐缓慢旋转，工件随滚筒炉罐旋转使之受热均匀，并且工件互相之间无复盖现象，热处理后色泽一致，炉罐另一端为进料口，由二只滚轮支承。

According to process discipline,the two mainshaft tail-wagging by electromotor.At the same time,two gun-barrel are ream processed by the reamer of the principal axes overlapping.

根据加工要求，由电动机带动两根主轴高速旋转，同时，连接在主轴上的铰刀对两根枪管同时进行铰削加工。

Suction valve and pressing-discharge valve must be closed up after the motor being shutted down .

1关闭电动机后，必须关闭吸入阀和压出阀。

To adopt band type rail rolled by stainless steel and chain type drive method run circumferential movement along with the pipe to be cut by flame cutting carriage,cutting torch will run radial movement driven by ball bearing screw by step motor along with the pipe to be cut,the above two dimension movement compose to inclined cutting movement of cutting torch,the inspection of circumference position of cutting torch,the determination of radial position and return point of cutting torch all controlled by SCM.

为了满足钢管斜截切割的要求，建立了钢管斜截切割的数学表达式，采用不锈钢轧制的带形轨道和链式传动的方式使火焰切割小车沿被切钢管做周向运动，割炬沿被切钢管的轴向运动由步进电动机带动滚珠丝杠完成，上述两维运动合成为割炬的斜切运动，割炬周向位置的检测、割炬轴向位置及折返点的确定均由单片机控制完成。

50Hz - 60Hz to get high rotary torque at low starting current, and also the motor at a lower starting

相交流电动机上作起动用，使电动机在较低的起动电流下得到较高的转矩。

Combing the SCM hardware resources with the software process,the system design completes the control functions such as digital impulse spring,digital logical switch and digital feedback,achieves a reversible adjustable-speed regulating control of DC electromotor,and improves the precision and control capability of reversible adjustable-speed regulating system.

利用单片机的硬件资源与软件程序相结合，完成数字脉冲触发、数字逻辑切换及数字反馈等方面的控制功能，实现对直流电动机的可逆调速控制，提高可逆调速系统的精度和控制性能。

The rotational spring includes a base member which is in the form of a ring and includes elements for fixedly attaching it to a body of an appliance, such as a power toothbrush, which includes a drive element such as a drive shaft portion of a motor.

一种旋转弹簧，包括形式为环件的底部件，并包括用于将其固定地连接到器具如电动牙刷的主体上的零件，该电动牙刷包括驱动件如电动机的驱动轴部分。

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。