<table id="iiomc"></table> 本應用筆記介紹一種采用dsPIC數字信號控制器（Digital Signal Controller，DSC）或PIC24單片機來實現無刷直流（Brushless Direct Current，BLDC）電機無傳感器控制的算法。該算法利用對反電動勢（Back-Electromotive Force，BEMF）進行數字濾波的擇多函數來實現。通過對電機的每一相進行濾波來確定電機驅動電壓換相的時刻。這一控制技術省卻了分立的低通濾波硬件和片外比較器。需指出，這里論述的所有內容及應用軟件，都是假定使用三相電機。該電機控制算法包括四個主要部分：·利用DSC或單片機的模數轉換器（Analog-to-Digital Converter，ADC）來采樣梯形波BEMF信號·PWM導通側ADC采樣，以降低噪聲并解決低電感問題·將梯形波BEMF信號與VBUS/2進行比較，以檢測過零點·用擇多函數濾波器對比較結果信號進行濾波·以三種不同模式對電機驅動電壓進行換相：-傳統開環控制器·傳統閉環控制器比例-積分（Proportional-Integral，Pl）閉環控制器
標簽： BLDC
上傳時間： 2022-07-01
上傳用戶：
本壓縮包上傳的源程序使用C語言編寫，可以進行二次開發，可移植性強！ADC（analog to digital converter）即模數轉換器，它可以將模擬信號轉換為數字信號。按照其轉換原理主要分為逐次逼近型、雙積分型、電壓頻率轉換型三種。STM32F1 的 ADC 就是逐次逼近型的模擬數字轉換器。STM32F103 系列一般都有 3 個 ADC，這些 ADC 可以獨立使用，也可以使用雙重/三重模式（提高采樣率）。STM32F1 的 ADC 是 12 位逐次逼近型的模擬數字轉換器。它具有多達 18 個復用通道，可測量來自 16 個外部源、2 個內部信號源。 這些通道的 A/D 轉換可以單次、連續、掃描或間斷模式執行。ADC 的結果可以左對齊或右對齊方式存儲在 16 位數據寄存器中。ADC 具有模擬看門狗特性，允許應用程序檢測輸入電壓是否超出用戶定義的閥值上限或者下限。
上傳時間： 2022-07-25
上傳用戶：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).
標簽： display Java applet either
上傳時間： 2014-01-12
上傳用戶：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.
標簽： applications for confined somewhat
上傳時間： 2016-10-29
上傳用戶：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.
標簽： computer-aided techniques developed assist
上傳時間： 2014-01-01
上傳用戶：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.
標簽： deferent_ready workpiece deferent program
上傳時間： 2017-08-31
上傳用戶：baiom
The bookl tell the analog Analog and Digital Communications and Analog and Digital Communications Laboratory
標簽： Communication Digital Systems
上傳時間： 2020-05-27
上傳用戶：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.
標簽： Communications Engineering Wireless Systems in
上傳時間： 2020-06-01
上傳用戶：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
標簽： Processing Digital Image
上傳時間： 2021-02-20
上傳用戶：
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
標簽： 控制系統
上傳時間： 2021-12-15
上傳用戶：
