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vector-space

  • vector调用

    关于使用vector调用参数的小程序,希望可以提供参考。(Eigen库)

    标签: vector

    上传时间: 2015-06-03

    上传用户:aikingke

  • svpwm matlab

    空间矢量脉宽调制(Space Vector Pulse Width Modulation)    SVPWM的主要思想是:以三相对称正弦波电压供电时三相对称电动机定子理想磁链圆为参考标准,以三相逆变器不同开关模式作适当的切换,从而形成PWM波,以所形成的实际磁链矢量来追踪其准确磁链圆。传统的SPWM方法从电源的角度出发,以生成一个可调频调压的正弦波电源,而SVPWM方法将逆变系统和异步电机看作一个整体来考虑,模型比较简单,也便于微处理器的实时控制。    普通的三相全桥是由六个开关器件构成的三个半桥。这六个开关器件组合起来(同一个桥臂的上下半桥的信号相反)共有8种安全的开关状态. 其中000、111(这里是表示三个上桥臂的开关状态)这两种开关状态在电机驱动中都不会产生有效的电流。因此称其为零矢量。另外6种开关状态分别是六个有效矢量。它们将360度的电压空间分为60度一个扇区,共六个扇区,利用这六个基本有效矢量和两个零量,可以合成360度内的任何矢量。    当要合成某一矢量时先将这一矢量分解到离它最近的两个基本矢量,而后用这两个基本矢量矢量去表示,而每个基本矢量的作用大小就利用作用时间长短去代表。    在变频电机驱动时,矢量方向是连续变化的,因此我们需要不断的计算矢量作用时间。为了计算机处理的方便,在合成时一般是定时去计算(如每0.1ms计算一次)。这样我们只要算出在0.1ms内两个基本矢量作用的时间就可以了。由于计算出的两个时间的总合可能并不是0.1ms(比这小),而那剩下的时间就按情况插入合适零矢量。 由于在这样的处量时,合成的驱动波形和PWM很类似。因此我们还叫它PWM,又因这种PWM是基于电压空间矢量去合成的,所以就叫它SVPWM了。 

    标签: matlab svpwm

    上传时间: 2016-04-25

    上传用户:bijiaohao22

  • Bi-density twin support vector machines

    In this paper we present a classifier called bi-density twin support vector machines (BDTWSVMs) for data classification. In the training stage, BDTWSVMs first compute the relative density degrees for all training points using the intra-class graph whose weights are determined by a local scaling heuristic strategy, then optimize a pair of nonparallel hyperplanes through two smaller sized support vector machine (SVM)-typed problems. In the prediction stage, BDTWSVMs assign to the class label depending on the kernel density degree-based distances from each test point to the two hyperplanes. BDTWSVMs not only inherit good properties from twin support vector machines (TWSVMs) but also give good description for data points. The experimental results on toy as well as publicly available datasets indicate that BDTWSVMs compare favorably with classical SVMs and TWSVMs in terms of generalization

    标签: recognition Bi-density machines support pattern vector twin for

    上传时间: 2019-06-09

    上传用户:lyaiqing

  • Complex Orthogonal Space-Time Processing

    Multiple-Input Multiple-Output (MIMO) systems have recently been the subject of intensive consideration in modem wireless communications as they offer the potential of providing high capacity, thus unleashing a wide range of applications in the wireless domain. The main feature of MIMO systems is the use of space-time processing and Space-Time Codes (STCs). Among a variety of STCs, orthogonal Space-Time Block Codes (STBCs) have a much simpler decoding method, compared to other STCs

    标签: Orthogonal Space-Time Processing Complex

    上传时间: 2020-05-26

    上传用户:shancjb

  • Free+Space+Optical+Communication+System

    Free Space Optical Communication (FSOC) is an effective alternative technology to meet the Next Generation Network (NGN) demands as well as highly secured (mili- tary) communications. FSOC includes various advantages like last mile access, easy installation, free of Electro Magnetic Interference (EMI)/Electro Magnetic Compatibil- ity (EMC) and license free access etc. In FSOC, the optical beam propagation in the turbulentatmosphereisseverelyaffectedbyvariousfactorssuspendedinthechannel, geographicallocationoftheinstallationsite,terraintypeandmeteorologicalchanges. Therefore a rigorous experimental study over a longer period becomes significant to analyze the quality and reliability of the FSOC channel and the maximum data rate that the system can operate since data transmission is completely season dependent.

    标签: Communication Optical System Space Free

    上传时间: 2020-05-27

    上传用户:shancjb

  • Space-Time+Processing

    Driven by the desire to boost the quality of service of wireless systems closer to that afforded by wireline systems, space-time processing for multiple-input multiple-output (MIMO) wireless communications research has drawn remarkable interest in recent years. Excit- ing theoretical advances, complemented by rapid transition of research results to industry products and services, have created a vibrant and growing area that is already established by all counts. This offers a good opportunity to reflect on key developments in the area during the past decade and also outline emerging trends.

    标签: Space-Time Processing

    上传时间: 2020-06-01

    上传用户:shancjb

  • Space-Time+Processing+for+Wireless+Communications

    In this thesis several asp ects of space-time pro cessing and equalization for wire- less communications are treated. We discuss several di?erent metho ds of improv- ing estimates of space-time channels, such as temp oral parametrization, spatial parametrization, reduced rank channel estimation, b o otstrap channel estimation, and joint estimation of an FIR channel and an AR noise mo del. In wireless commu- nication the signal is often sub ject to intersymb ol interference as well as interfer- ence from other users. 

    标签: Communications Space-Time Processing Wireless for

    上传时间: 2020-06-01

    上传用户:shancjb

  • Star Trek_ Deep Space Nine - A Stitch in Time

    Star Trek_ Deep Space Nine - A Stitch in Time - Andrew J. Robinson 英文版 格式 epub

    标签: Stitch Space Star Deep Nine Trek Time in

    上传时间: 2021-06-17

    上传用户:potato

  • 基于TMS320F28035芯片为控制核心的空间矢量异步电机变频器

    基于TMS320F28035芯片为控制核心的空间矢量异步电机变频器  我们设计的异步电机变频调速器以TMS320F28035芯片为控制核心,通过输出三相PWM波控制智能功率模块IPM驱动三相异步电机。我们使用空间矢量SVPWM算法,并对其进行了优化。采用检测反电势的方法省去了昂贵的光电编码器,大大节省了成本。同时开创性的研发了自动根据运行环境调节的自适应变频算法,使我们的变频调速器可以在电网条件恶劣的乡村山区工作,由此该变频器已被一家民用水泵生产企业预订。关键字 变频器 TMS320f28035 IPM SVPWM In our design, the asynchronous machine inverter based on the chip of TMS320F28035 drives the three-Phase asynchronous machine by sending three-phase PWM waves to the IPM, which is short for the Intelligent-Power-Module. The SVPWM (space vector pulse width modulation) strategy is applied to our control algorithm and we optimize it mainly in two aspects. Firstly the inverter detects the speed by measuring the Back EMF instead of installing an expensive photoelectric encoder for costs reduction. 

    标签: tms320f28035 芯片

    上传时间: 2022-05-08

    上传用户:zhanglei193

  • 使用dsPIC30FDSC实现PMSM电机的正弦驱动

    简介本文档介绍了如何使用dsPIC30F数字信号控制器(Digital Signal Controller,DSC)控制正弦电流来驱动具有位置传感器的永磁同步电机(Permanent Mag-net Synchronous Motor,PMSM).电机控制固件使用dsPIC30F外设,而数学运算则由DSP引擎完成。为充分利用dsPIC30F的特殊DSP运算性能,固件采用C语言编写,只有某些子程序采用汇编语言编写。应用特性·使用空间矢量调制(Space Vector Modulation,SVM)方法产生用于驱动PMSM电机各相的正弦电流·正弦电压与PMSM电机转子位置同步·四象限运行,可实现正向、反向和制动运行·基于数字比例一积分一微分(Proportional Integral Derivative,PID)控制的闭环转速控制·相位超前技术可实现更宽的调速范围·由dsPICODSC的DSP引擎实现小数数学运算

    标签: pmsm 电机

    上传时间: 2022-07-05

    上传用户: