查询词典 back current

In this paper, the change of back electromotive force current with the different PWM modes are analyzed in detail on the base of BLDCM model. According to theory and experiment ,ON-PWM type restrains the peak value of back electromotive force current and brings the lest effect to the motor control system.

基于无刷直流电动机的数学模型，分析比较了不同PWM调制方式下反电势电流的变化规律，并通过理论推导和仿真实验证明了当电机系统采用ON-PWM调制方式时，能有效地抑制反电势电流的峰值且对电机控制系统造成的影响最小。

The results indicate that back electromotive force increases with increasing current density and decreases by 0.5 V after adding 2% Li2CO3, the feeding period is 15 min measured by the method of electric potential control. Finally, the Al-Li alloy with the lithium content of 7.93% can be obtained by electrolyzing for 3 h at the current density of 0.62 A/cm^2 and at 680 ℃, and the current efficiency can reach 74.1%.

结果表明，反电动势随电流密度增加而增大，加入2%的Li2CO3可使反电动势降低0.5V；通过控制电位法测得加料周期为15 min：在680℃、电流密度为0.62A/平方公分的条件下持续电解3h，最终制得了理含量高达7.93%的铝锉合金，电流效率可达74.1%。

The thesis first probably explains BrushLess Direct Current Motor, and discusses the related control methods, explains the background and Meaning of back electromotive force which is used in the thesis.Then the thesis expounds the basic component parts,the basic running principle,the running characteristic and transfer function of the BLDCM.And then the thesis detailedly dissertates its research pivot: the simulation of BLDCM system in MATLAB based on the method of Back-EMF and the control system of Digital Signal Processor based on the method of Back-EMF.

本文首先对无刷直流电机进行了概述，并对其相关控制方法进行了讨论，说明本文所采用反电动势法的背景和意义；接着论述了无刷直流电机基本组成环节、基本工作原理、运行特性和传递函数，然后是详述本文研究的重点：基于反电动势法的MATLAB调速系统的仿真以及基于反电动势法的DSP控制系统的实现。

The principle of constant power drive is: PD converts the change of output light power of laser diode into the change of diode current, and the change of current is feed back to voltage-current converser which adjusts output current of driver to compensate the laser diode.

这样，当激光器的输出光功率衰减时，驱动器相应的增大输出电流；当激光器的输出光功率增强时，驱动器就相应减小输出电流。对许多激光器应用来说，最希望脉冲输出，因为脉冲输出只有极小的结发热。

Korea put the company at electric power control device - the general type STR (thyratron thyristor power controller) CPU upgrade to system memory type, and early in 2003 to develop cutting-edge new product type constant current, constant voltage type collectively referred to as STR (may silicon-controlled thyristor power controller) the inherent brand. In 2000 to develop the motor starting device - soft starter motor new products and the inherent SMC brand available at the area of power control both at home and abroad alike. Market in 2000 and 2002 patent SSC (packaged solid-state thyratron power controller), as well as sales from the company since its inception back filter with Pulse Timer and other products in the same trade firmly occupy The largest market. Also in 2002 the development of the supply of silicon wafer characterization equipment and sub-Plasma Ion Plating with the most cutting-edge power supply devices and so on, so if the company has high-speed development.

本公司在韩国把电炉电力控制装置-一般型STR升级为CPU系统内存型，与2003年初新开发的尖端产品恒电流型、恒电压型统称为STR 这一固有品牌。2000年开发电动机启动装置-电动机软启动器新产品并以SMC这一固有品牌面市，在电力控制领域受到国内外的一致好评。2000年面市并2002年取得专利的SSC(封装固态闸流功率控制器)，还有从公司创立初期销售至今的 back filter 用 Pulse Timer等产品在同行业中牢牢占据着最大的市场。2002年又开发供应硅wafer分段定性装备及Plasma Ion Plating用最尖端动力供应装置等，因此公司具备了高速发展的依据。

Companies for faster and better development of the cause of flower protocol, we conclude the Protocol on the flower market success abroad, the development and promotion of the concept of protocol in combination with the current domestic flower industry and confusion inferior products, for which the Company decided to our high quality and low price The South Flower Product licensing protocol comprehensively push the domestic market, let · Yen tease pyridaben bad Mei Wan Street, as the spouse happy Bo Mu Mu addiction al-contracting small-minded ¨ú noise penalty Dy fat gray eyes addiction ¨ú back satisfied small-minded Mikasa Island úú properly wood pigeon Mok blown addiction ¨ small-minded exploration helter-skelter to make meal times ¤§ addiction drunk camel small-minded Tam Yiu-mortem veranda Donowaki coarse meal Yong Jue addiction ¨ú small-minded Kang persimmon head back to downtown Terrier turbulent Metaplexis stauntoni enzyme ü meal is cheap · Mu Yen addiction ¨ garrulous small-minded circle back to head-gap ú¨?

公司为了更快更好的发展礼宾花事业，我们总结对国外礼宾花市场成功发展和推广的理念并结合目前国内礼宾花行业产品的低劣和混乱，为此本公司决定把我公司质优价廉的中南牌礼宾花产品全面推向国内市场，让颜哒嬲芄坏玫街视偶哿⒊菩姆判牡睦癖龌ú罚颐窍嘈胖灰癖龌ú返纳笠岛妥鹁吹睦癖龌ㄉ探缤使餐次ず驼湎Ю癖龌ㄕ庑胁担餐粗厥永癖龌ú返闹柿亢头⒄梗湍芄餐酶嗟睦癖龌ㄏ颜叨圆返目隙ā？

In this paper, the sorting of wear, the mechanics of wear particle formed and the characteristics of wear particles are introduced, and morphology characteristics parameter of wear particle are determined, which is particle brim digital feature. Based on image characters, after pre-process, section and extracting of contour parameter of wear particle using image process technique, four shape character parameters are extracted by fourier series expansion. After analyzing fundamental principle and shortcomings of neural network, current BP algorithm is improved in output optimization, network linearization implication optimization and adding momentum, and then astringe speed of BP algorithm.

本文介绍了磨损的分类以及磨粒的生成机理、磨粒的形态特征，应用摩擦学系统分析的观点，确定磨粒边缘数字特征为磨粒的识别特征参数；根据磨粒图像的特征，利用计算机图像处理技术对磨粒图像进行预处理、分割、轮廓参数的提取，采用傅立叶级数展开式提取磨粒四个形状特征参数：圆形度、散射度、凹度、细长度；针对 BP(Back-Propagation)神经网络收敛速度慢的特点，对现行的 BP 算法进行改进，并通过实验验证改进后的网络收敛速度快；研究设计了磨粒图像采集系统；利用 BP 算法建立磨损磨粒自动识别算法模型 AWPRM(Auto Wear Particle Recognition Model)。

A sensing circuit senses a black current level of the electron beam corresponding to the black level of the video signal and feeds back information about the black current level to the black level controlling circuitry for stabilizing the black current level.

检测电路对与视频信号的黑色电平相对应的电子束的黑色电流电平进行检测，并将与黑色电流电平有关的信息反馈给黑色电平控制电路，以便稳定黑色电流电平。

The boost converter is a voltage step-up and current step-down converter .the current source is synthesized from a DC voltage source by adding a large value inductor in series .in DC regulated power supply applications ,the voltage sink represents a large value capacitor in parallel with the load resistance .in the application of the DC motor control ,the voltage sink represents the back emf of the DC motor .the switching action produces a pulsating current .the capacitive filter smoothens the pulsating current and provides a DC voltage to the load

升压转换器是一个升压和降流的转换器。电流源是一个直流电压源添加一个大值电感串联合成的。在直流稳压电源的应用，电压降代表一个大值电容并联一个负载电阻。在直流电机的控制应用中，电压降代表反电动势的直流电机。转换行为产生一个脉动电流。一个滤波电容是这个脉动电流平和并且提供直流的电压负荷。

Just as I had set my Mast and Sail, and the Boat began to stretch away, I saw even by the Clearness of the Water, some Alteration of the Current was near; for where the Current was so strong, the Water was foul; but perceiving the Water clear, I found the Current abate, and presently I found to the East, at about half a Mile, a Breach of the Sea upon some Rocks; these Rocks I found caus'd the Current to part again, and as the main Stress of it ran away more Southerly, leaving the Rocks to the North-East; so the other return'd by the Repulse of the Rocks, and made a strong Eddy, which run back again to the North-West, with a very sharp Stream.

我刚竖起桅杆张好帜，船就开始向前行驶了。我发现四周水色较清，知道那股急流在附近改变了方向。因为，水急水则浊，水缓水则清，我知道那股急流在这儿已成了强弩之末了。不久我果然发现，在半海里以外，海水打在一些礁石上，浪花四溅。那些礁石把这股急流分成两股，主要的一股继续流向南方，另一股被礁石挡回，形成一股强烈的回流，向西北流回来，水流湍急。

Finally, according to market conditions and market products this article paper analyzes the trends in the development of camera technology, and designs a color night vision camera.

最后根据市场情况和市面上产品的情况分析了摄像机技术的发展趋势，并设计了一款彩色夜视摄像机。

Only person height weeds and the fierce looks stone idles were there.

只有半人深的荒草和龇牙咧嘴的神像。