pulse width modulation and inverter

... 229 230 231 233 233 240 242 242 247 254 255 257 257 258 10 Pulse- Width Modulation and Inverter 10.1 Switching Functions and Six-Step Operation 10.2 PWM Methods ... microcontroller i) command holder, ii) computing cycle time, iii) pulse- width modulation (PWM) execution delay, iv) value detection The command is refreshed every sampling period Since the command value is ... Ti and ω2 = τ1 , and divide the whole frequency range into three parts: σ [0, ω1 ), [ω1 , ω2 ), and [ω2 , ∞) Note that [0, ω2 ] representing the current bandwidth / is larger than the speed bandwidth...

Ngày tải lên: 24/07/2015, 13:53

... bandwidth demand exceeds available bandwidth or if there is contention on the line between different types of traffic Enterprises that are in the former situation simply need to add more bandwidth ... must scale to support an ever-increasing pool of users and demands for processing and bandwidth Systems need to support load balancing and fault tolerance so that end users perceive that the ... apply bandwidth management techniques to prioritize and shape traffic more effectively Remote user access to the campus network is very diverse In some cases, the enterprise can control the bandwidth...

Ngày tải lên: 24/10/2013, 07:20

Ngày tải lên: 21/02/2014, 13:20

... ĐIỆN TỬ/ MATERIALS AND MICROELECTRONIC PROCESSES IV THIẾT KẾ LINH KIỆN VÀ XÂY DỰNG QUY TRÌNH CHẾ TẠO/ MEMS DESIGN V VI CHẾ TẠO VÀ PHÂN LOẠI CÔNG NGHỆ MEMS/ MICROFABRICATION AND MEMS TECHNOLOGY ... thu nhỏ kích thước / Scaling issues for MEMS g Mô hình hóa mô phỏng/ Modeling d Simulation M d li and Si l ti Thiết kế qui trình chế tạo/ Process integration Kết luận/Conclusions 4.1 Mở đầu 4.1.1.Vai ... thước / Scaling issues for MEMS design g g Mô hình hóa mô phỏng/ Modelling d Simulation M d lli and Si l ti Thiết kế qui trình chế tạo/ Process integration Kết luận/Conclusions 4.2 Các hệ thu...

Ngày tải lên: 23/04/2014, 10:18

... thu nhỏ kích thước / Scaling issues for MEMS g Mô hình hóa mô phỏng/ Modeling d Simulation M d li and Si l ti Thiết kế qui trình chế tạo/ Process integration Kết luận/Conclusions 4.3 Mô hình hóa ... (effort): e(t) Biến liên hợp: e(t).f(t) = NL Biến đổi (flow): f(t) Xung lượng chuyển vị (momentum and displacement) t Xung lượng p (t ) = ∫ e(t )dt t t0 Chuyển vị q (t ) = ∫ f (t )dt t0 ⇒ e(t).q(t) ... thu nhỏ kích thước / Scaling issues for MEMS g Mô hình hóa mô phỏng/ Modeling d Simulation M d li and Si l ti Thiết kế qui trình chế tạo/ Process integration Kết luận/Conclusions 4 Thiết kế qui...

Ngày tải lên: 23/04/2014, 10:18

... Example Energy and Coenergy Energy and coenergy in singly excited systems Energy and coenergy in doubly excited systems Coenergy in the presence of a permanent magnet Force, Torque, and Power Basic ... opportunities provided by Mike and his staff Moreover, it would not have been possible without the commitment and dedication of my wife Pamela and our children Ruth, Sarah, and Kevin Duane C Hanselman ... Includes bibliographical references and index ISBN 0-07-026025-7 (alk paper) Electric motors, Permanent magnet—Design and construction Electric motors, Brushless—Design and construction I Title TK2537.H36...

Ngày tải lên: 02/07/2014, 08:20

... the numerator and denominator of (2.27) by AmAg and simplifying gives P - - V t k (2'28) where Vm and Vg are the magnet and air gap volumes, respectively Now if Crf, is doubled to 2C and the air ... and (2.15) applies strictly to materials that are linear, homogeneous (have uniform properties), and isotropic (have the same properties in all directions) Despite this fact, however, (2.1) and ... small for low excitations, increases and peaks at medium excitations, and finally decreases for high excitations At very high excitations, ¡xd approaches 1, and the material is said to be in hard...

Ngày tải lên: 02/07/2014, 08:20

... slot bottom width The unknown parameters in this design are the slot dimensions The width of the stator teeth varies with radius After the tooth width at the slot bottom and back iron width are ... insertion into a slot The unknowns in the above equations are the back iron widths of the rotor and stator wbl and the tooth width wtb- Given these two dimensions, all other dimensions can be found ... (4.11) and (4.12), respectively, and can be evaluated using thefixed and known geometric parameters given above As discussed in Chap 4, the flux from each magnet splits equally in both the stator and...

Ngày tải lên: 02/07/2014, 08:20

... understand is the turnoff behavior of the H bridge and how phase current is controlled to limit its magnitude Current control is accomplished by chopping, i.e., employing pulse- width- modulation ... simple and inexpensive In many applications, the cost of higher performance cannot be justified H-bridge circuitry Based on Figs 7.3 and 7.4 it is necessary to send positive and negative current pulses ... as Leonhard (1985), and Murphy and Turnbull (1988) With this intuitive understanding, more complex drive schemes are readily understood Two-Phase Motors Until now, torque and back emf expressions...

Ngày tải lên: 02/07/2014, 08:20

... Holtz, J (1992), "Pulsewidth Modulation A Survey," IEEE Transactions on Industrial Electronics vol 39, no 5, pp 410-420 Huang, H W M Anderson, and E F Fuchs (1990), "High-Power Density and High Efficiency ... W/m2) Q r Radius (m) V Velocity (m/s) Back iron width (m) Wbi ws Slot width (m) Slot bottom width (m) Wsb Tooth width (m) Wt Wtb Tooth bottom width (m) r acp «m OTS a sd P PR Pa Pd Pr Po Core ... influence and limit motor design and performance Hanselman also discusses brushless DC and synchronous motor design for both cylindrical (radial) and pancake (axial) topologies All the concepts and...

Ngày tải lên: 02/07/2014, 08:20

... containing ns conductors connected in series is where L is the slot length, ws and ds are the slot width and height, respectively, and kcp, the conductor packing factor, is the ratio of crosssectional ... rectangular area having height d2 and average width (ws + wsbV2, and the third term is the permeance of the shoe tip area In some texts, /JL0L is factored out and the terms remaining inside the ... the torque and back emf produced must be computed by applying the BLi and BLv laws, respectively, to each coil in every winding Clearly this is an overwhelming task to perform by hand, and the resulting...

Ngày tải lên: 02/07/2014, 08:20

... voltage controllers ♦ Rectifier -inverter systems with line commutation ♦ Rectifier -inverter systems with self-commutation ♦ Pulse- width modulation systems Pulse- width modulation systems are the only ... considered for this thesis as the motor controller is specifically designed for Pulse- width modulation The text by Mohan, Undeland and Robbins [2] gives good explanations on the operating principles of ... PWM (Pulse Width Modulation) outputs Six of these will be utilized to drive the three-phase MOSFET bridge inverter on the motor controller board • UART (Universal Asynchronous Receiver and Transmitter),...

Ngày tải lên: 27/10/2013, 23:15

Ngày tải lên: 23/03/2014, 23:20

... that sometimes encumbers this shorthand label, and when we talk of the National Curriculum we mean the England and Wales curriculum – Scotland and Northern Ireland have their own versions However, ... understanding of aesthetics, social and environmental issues, function and industrial practices As they so, they reflect on and evaluate present and past design and technology, its uses and effects ... autonomous and creative problem solvers, as individuals and members of a team They must look for needs, wants and opportunities and respond to them by developing a range of ideas and making products and...

Ngày tải lên: 24/03/2014, 02:20

... Giangrandi, P., and Tasso, C (1988) The ET Project: Artificial intelligence in second language teaching.In: F Lovis and E.D Tagg (Eds), Computers in Education Amsterdam, The Netherlands: NorthHolland, ... 1987): deictic (between reference time and speaking time: RT-ST), intrinsic (between event time and reference time: ET-RT) and ordering (between event time and speaking time: ETST) When these relations ... illustrates the ET general architecture and mode of operation Section four constitutes the core of the paper and presents the design requirements, knowledge bases and reasoning algorithms of the verb...

Ngày tải lên: 01/04/2014, 00:20

... configuration of machines and servers and a certain budget for storing items In Chapter 11, Van Nyen, Bertrand, van Ooijen, and Vandaele present a heuristic that minimizes the relevant costs and satisfies ... production-inventory systems with job shop routings and stochastic arrival, set-up and processing times P L M van Nyen, J W M Bertrand, H P G van Ooijen and N J Vandaele 253 Performance analysis of ... (there can be hundreds) and their input rates and raw material requirements, the constraint relationships with the machines, people, resources, and materials handling equipment, and the functional...

Ngày tải lên: 08/04/2014, 12:26

... multiple operating points that have different power consumption and quality of MV search 3.3.4 Bandwidth and storage Memory bandwidth and on-chip memory capacity are limiting factors for many multimedia ... modules and between modules and memory is so frequent, dedicated bus between modules is a better solution and local memory is required to reduce the bandwidth requirement between modules and memory ... forms the basis of image and video coding standards For image coding standards, JPEG selects DCT [7] as its transformation, and JPEG 2000 adopts DWT For current video coding standards, DCT is the...

Ngày tải lên: 05/05/2014, 13:35

... schedule with frequent rest periods) and random ordering of taskrelated exercises improves performance and learning [3,80] A good interchange between loading and adequate rest intervals are necessary ... feedback, BW = bandwidth) Page of 18 (page number not for citation purposes) Journal of NeuroEngineering and Rehabilitation 2009, 6:1 http://www.jneuroengrehab.com/content/6/1/1 attention and awareness ... patient's hand through a handle that is connected to the end-effector of the robot This robot treatment focuses on shoulder and elbow function The MIME system can work in preprogrammed position and...

Ngày tải lên: 19/06/2014, 08:20

... Finland Hilkka Merisalo-Rantanen, Helsinki School of Economics, Finland Tuure Tuunanen, The University of Auckland, New Zealand Chapter II Understanding Agile Software, Extreme Programming, and ... has evolved and become more and more streamlined The working methods and standards are discussed and, if necessary, changed by developers weekly Coding rules especially are strictly standardized ... analysis and design, databases and software development / Keng Siau, editor p cm Summary: "This book is designed to provide understanding of the capabilities and features of new ideas and concepts...

Ngày tải lên: 27/06/2014, 06:20