本应用笔记介绍一种采用dsPIC数字信号控制器（Digital Signal Controller，DSC）或PIC24单片机来实现无刷直流（Brushless Direct Current，BLDC）电机无传感器控制的算法。该算法利用对反电动势（Back-Electromotive Force，BEMF）进行数字滤波的择多函数来实现。通过对电机的每一相进行滤波来确定电机驱动电压换相的时刻。这一控制技术省却了分立的低通滤波硬件和片外比较器。需指出，这里论述的所有内容及应用软件，都是假定使用三相电机。该电机控制算法包括四个主要部分：·利用DSC或单片机的模数转换器（analog-TO-DIGITAL Converter，ADC）来采样梯形波BEMF信号·PWM导通侧ADC采样，以降低噪声并解决低电感问题·将梯形波BEMF信号与VBUS/2进行比较，以检测过零点·用择多函数滤波器对比较结果信号进行滤波·以三种不同模式对电机驱动电压进行换相：-传统开环控制器·传统闭环控制器比例-积分（Proportional-Integral，Pl）闭环控制器
标签： BLDC
上传时间： 2022-07-01
上传用户：
本压缩包上传的源程序使用C语言编写，可以进行二次开发，可移植性强！ADC（analog to digital converter）即模数转换器，它可以将模拟信号转换为数字信号。按照其转换原理主要分为逐次逼近型、双积分型、电压频率转换型三种。STM32F1 的 ADC 就是逐次逼近型的模拟数字转换器。STM32F103 系列一般都有 3 个 ADC，这些 ADC 可以独立使用，也可以使用双重/三重模式（提高采样率）。STM32F1 的 ADC 是 12 位逐次逼近型的模拟数字转换器。它具有多达 18 个复用通道，可测量来自 16 个外部源、2 个内部信号源。 这些通道的 A/D 转换可以单次、连续、扫描或间断模式执行。ADC 的结果可以左对齐或右对齐方式存储在 16 位数据寄存器中。ADC 具有模拟看门狗特性，允许应用程序检测输入电压是否超出用户定义的阀值上限或者下限。
上传时间： 2022-07-25
上传用户：zhanglei193
Java Clock is a FREE Java applet used to display a clock on your Web pages. You can display either analog or digital clock. The full source code of this applet is also available (visit my home page to download it). You may use this applet on your Web pages WITHOUT paying me fee or royalty as long as credit is given (a link to my home page is enough).
标签： display Java applet either
上传时间： 2014-01-12
上传用户：woshiayin
A few short years ago, the applications for video were somewhat confined—analog was used for broadcast and cable television, VCRs, set-top boxes, televisions and camcorders. Since then, there has been a tremendous and rapid conversion to digital video, mostly based on the MPEG-2 video compression standard. Today, in addition to the legacy DV, MPEG-1 and MPEG-2 audio and video com- pression standards, there are three new high- performance video compression standards. These new video codecs offer much higher video compression for a given level of video quality.
标签： applications for confined somewhat
上传时间： 2016-10-29
上传用户：bjgaofei
A large body of computer-aided techniques has been developed in recent years to assist in the process of modeling, analyzing, and designing communication systems . These computer-aided techniques fall into two categories: formula-based approaches, where the computer is used to evaluate complex formulas, and simulation-based approaches, where the computer is used to simulate the waveforms or signals that flow through the system. The second approach, which involves “waveform”-level simulation (and often incorporates analytical techniques), is the subject of this book. Since performance evaluation and trade off studies are the central issues in the analysis and design of communication systems, we will focus on the use of simulation for evaluating the performance of analog and digital communication systems with the emphasis on digitalcommunication systems.
标签： computer-aided techniques developed assist
上传时间： 2014-01-01
上传用户：541657925
Main program running when workpiece is ready on deferent belt(deferent_ready=ture). * Call Square_Wave subroutine to generate 0.5ms square wave on P1.2 to drive * electromotor,then drive deferent belt step forward. When it steps to the measure * zone, it stops to be measured. Then call A_D subroutine to transform analog * signals to digital signals , after then call serial subroutine to transfer * digital signals to PC. Call square wave subroutine to drive deferent belt step to * original position waitting for defere ready flag to run the next circle.
标签： deferent_ready workpiece deferent program
上传时间： 2017-08-31
上传用户：baiom
The bookl tell the analog Analog and Digital Communications and Analog and Digital Communications Laboratory
标签： Communication Digital Systems
上传时间： 2020-05-27
上传用户：shancjb
In Helsinki during a visiting lecture, an internationally well-known professor in communica- tionssaid,‘Inthecommunicationssocietywehavemanagedtoconvertourproposalsandideas to real products, not like in the control engineering society. They have very nice papers and strong mathematics but most of the real systems still use the old PID controllers!’. As our background is mainly in control as well as communications engineering, we know that this thought is not very accurate. We agree that most of the practical controllers are analog and digital PID controllers, simply because they are very reliable and able to achieve the required control goals successfully. Most of the controllers can be explained in terms of PID. The reasons behind this impressive performance of PID will be explained in Chapter 2.
标签： Communications Engineering Wireless Systems in
上传时间： 2020-06-01
上传用户：shancjb
This edition of Digital Image Processing is a major revision of the book. As in the 1977 and 1987 editions by Gonzalez and Wintz, and the 1992, 2002, and 2008 editions by Gonzalez and Woods, this sixth-generation edition was prepared with students and instructors in mind. The principal objectives of the book continue to be to provide an introduction to basic concepts and methodologies applicable to digital image processing, and to develop a foundation that can be used as the basis for further study and research in this field. To achieve these objectives, we focused again on material that we believe is fundamental and whose scope of application is not limited to the solution of specialized problems. The mathematical complexity of the book remains at a level well within the grasp of college seniors and first-year graduate students who have introductory preparation in mathematical analysis, vectors, matrices, probability, statistics, linear systems, and computer programming. The book website provides tutorials to support readers needing a review of this background material
标签： Processing Digital Image
上传时间： 2021-02-20
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This texts contemporary approach focuses on the concepts of linear control systems, rather than computational mechanics. Straightforward coverage includes an integrated treatment of both classical and modern control system methods. The text emphasizes design with discussions of problem formulation, design criteria, physical constraints, several design methods, and implementation of compensators.Discussions of topics not found in other texts--such as pole placement, model matching and robust tracking--add to the texts cutting-edge presentation. Students will appreciate the applications and discussions of practical aspects, including the leading problem in developing block diagrams, noise, disturbances, and plant perturbations. State feedback and state estimators are designed using state variable equations and transfer functions, offering a comparison of the two approaches. The incorporation of MATLAB throughout the text helps students to avoid time-consuming computation and concentrate on control system design and analysis
标签： 控制系统
上传时间： 2021-12-15
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