fundamentals of digital video coding

... speed The LRC of a motor can range from 500% of Full-Load Current (FLC) to as high as 1400% of FLC Typically, good motors fall in the range of 550% to 750% of FLC The starting torque of an induction ... as 350% of FLT The pull-up torque can be as low as 40% of FLT and the breakdown torque can be as high as 350% of FLT Typically, LRTs for medium to large motors are in the order of 120% of FLT ... period of operation at no-load There is no rest period S7 Continuous operation A sequence of identical duty cycles, each consisting of a period of starting, a periodic duty with electric period of...

Ngày tải lên: 25/01/2014, 13:20

... the frequency of the output voltage of the inverter The frequency of the carrier triangle wave of the PWM determines the frequency of the transistor switches and the resulting number of square notches ... transistors turn on and off The frequency of the fundamental sine wave of the PWM determines the frequency of the output waveform to the motor The frequency of the carrier triangle wave of the PWM determines ... will improve the shaping of the switching trajectory of the switch as it turns off The turn-off snubber provides zero voltage across the transistor while the current turns off A configuration for...

Ngày tải lên: 17/12/2013, 18:06

... features of our products Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act If such acts allow unauthorized access to your software ... Programmable digital noise filters on inputs - Alternate 16-bit Timer/Counter mode - Interrupt on position counter rollover/underflow Table lists the most important software modules: SOFTWARE DMCI ... to be normalized to fit the software control algorithm - in order to support the ease of actual control solution porting for other system components within the software archive it may be found...

Ngày tải lên: 11/01/2016, 16:47

... operation: The determination of magnetizing current as a function of rotor speed is achieved with a series of open loop V/ Hz, no load experiments For each series of experiments, the V/Hz ratio ... features of our products Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act If such acts allow unauthorized access to your software ... ratio, it is recommended to put most of the current increase in the torque-producing current component The power limit of the inverter and the necessity of speed increase can be achieved by delivering...

Ngày tải lên: 11/01/2016, 17:01

... quarter of the resonance period of L and C of the MERS, vmers, becomes sinusoidal, consequently the terminal voltage,vterm, also becomes sinusoidal Fig shows simulated waveforms of 'dc-offset ... Applications of voltage control of induction motor were investigated Stability problem because of self-excitation of series com- 924 Authorized licensed use limited to: TOKYO INSTITUTE OF TECHNOLOGY ... cycle of the ac power source and controlled synchronously The phase difference between the voltage of the power source and the switching can be controlled The principle of the operation of the...

Ngày tải lên: 15/10/2013, 16:10

... Head of School, School of Information Technology and Electrical Engineering, University of Queensland, St Lucia, Qld, 4072 Dear Professor Simon Kaplan, In accordance with the requirements of the ... supervision of Dr Geoff Walker, a group of Computer Science and Electrical Engineering Ph.D students at the University of Queensland are constructing a hybrid or an electric car Both of these types ... per revolution Based on this, the software section of the design must interrupt the speed of the rotor based on the number of pulses it receives The rated speed of the induction motor used in this...

Ngày tải lên: 27/10/2013, 23:15

... method Figure 4.11: Variation of DC bus voltage of a 3-in case of open loop PI control for constant V/f control method Figure 4.12: Variation of Torque of a 3-in case of open loop PI control for ... Figure 4.15: Variation of Stator current of a 3-in case of closed loop PI control for constant V/f control method Figure 4.16: Variation of DC Bus Voltage of a 3-in case of closed loop PI control ... method Figure 4.17: Variation of Torque of a 3-in case of closed loop PI control for constant V/f control method Figure 4.18: Variation of Rotor Speed of a 3-in case of closed loop PI control...

Ngày tải lên: 18/12/2013, 22:06

... plots of (5) and (6) in mode which are at higher voltages Note that the curves are not symmetrical because of saturation The saturation of in sector mode is eviat dent from the waveforms of Fig ... availability of a large economical digital ASIC chip with high resolution MONDAL et al.: A NEURAL-NETWORK-BASED SPACE VECTOR PWM CONTROLLER ACKNOWLEDGMENT The authors wish to acknowledge the help of Prof ... Chairman of the IEEE Industry Applications Society (IAS) Industrial Power Converter Committee, and IAS member of the Neural Network Council He has been a Member of the Editorial Board of the PROCEEDINGS...

Ngày tải lên: 22/12/2013, 08:16

... bearings Bearing type of D-end Bearing type of ND-end Lubrication interval Quantity of grease for D-end bearing Quantity of grease for ND-end bearing Additional information Type of grease delivered ... Scope of delivery 3.5.2 Check of foundation 3.5.3 Erection of machines 3.5.4 Alignment 3.5.5 Final installation and inspection 3.5.5.1 Doweling of ... maintenance of rotating electrical machines manufactured by ABB This manual provides information regarding all aspects of operation, maintenance and supervision of the machine Careful study of the...

Ngày tải lên: 26/01/2014, 09:20

... CONTROL One of the problems of the control strategy presented is that it is a function of the parameters of the machine Because of magnetic nonlinearities and the distributed nature of the machine ... unity regardless of the actual value of the parameters Hence, this term will not be a strong function of the parameters of the machine The second term in (13.6-1) is a strong function of the leakage ... density, i is the current, N is the number of turns, L is the length of the coil into the page, and r is the radius of the coil Clearly, the magnitude of the torque is maximized when the current...

Ngày tải lên: 16/02/2014, 18:54

... on the business of fashion The CFDA is committed to working hard on behalf of the fashion industry to help designers succeed As president of the Council of Fashion Designers of America, I represent ... Arnold, the former executive director of the Council of Fashion Designers of America (CFDA), now president and CEO of Cynthia Rowley, says, “Virtually all of today’s successful designers have ... the more your design will reflect this sense of liberty, which is after all, one of the essences of fashion Fashion tends to represent different points of view and meaning, and at its best should...

Ngày tải lên: 03/04/2014, 18:02

... determine the sector of the desired input current ii This controller is also necessary for active damping of oscillations of the input current which arise from the low cutoff frequency of the input filter ... Improvement of the Input Line Current Quality,” Proc of EPE’01, Graz, Austria, CD-ROM paper [9] D Casadei, G Serra and A Tani, “The Use of Matrix Converters in Direct Torque Control of Induction ... small hexagon at the tip of this vector indicates the directions ∆ Ψ S , in which the stator flux vector may be changed within one switching period T by application of one of the voltage vectors...

Ngày tải lên: 13/05/2014, 00:55

... principle of operation of an AC-AC controller is very simple, analysis of the system of Fig 6.5 is extremely tedious even for steady-state operation This is so because of the inductive nature of the ... control of induction motors The second one, current source inverter (CSI), is beyond the scope of interest here Principle of operation of a threephase VSI is explained next Three-phase version of ... 0.816VDC Rms values of the fundamental and of the whole waveform are given in (6.17) as well Selection of appropriate DC voltage for V/f control is done on the basis of the rms of the fundamental...

Ngày tải lên: 11/07/2014, 05:20

... current per phase at a slip of 0.04, (d) the phase difference between the rotor emf and current at a slip of 0.04 Answer: 0.01565 Wb/pole, 80 V, 243.5 A, 8.45o The parameters of the equivalent circuit ... and core losses may be assumed to be constant at 403 W, independent of load Neglect the impedance of the power supply For a slip of 2.0% and when the motor is operated at the rated voltage and frequency, ... (b) the rotor current frequency, (c) the speed of the rotor rotating magnetic field with respect to the stator frame in rev/min, (d) the speed of the rotor rotating magnetic field with respect...

Ngày tải lên: 11/07/2014, 05:20

... the examiners of this thesis, Professor Young-Soo Suh, Professor Jin Hur, Professor Myeong-Jae Yi, and Professor Heung-Geun Kim for their valuable comments and corrections ii Table of Contents ... submitted to the School of Electrical Engineering in fulfillment of the thesis requirements for the degree of Doctor of Philosophy in the Graduate School, University of Ulsan December 2008 Abstract ... School of Electrical Engineering, University of Ulsan The work has been done during 20052008 under the support of the Research Fund of University of Ulsan and the Network-based Automation Research...

Ngày tải lên: 13/11/2014, 06:43

... MONITORING OF INDUCTION MOTOR LU WENJING (B.ENG NUS) A THESIS SUBMITTED FOR THE DEGREE OF MASTER OF ENGINEERING DEPARTMENT OF ELECTRICAL AND COMPUTER ENGINEERING NATIONAL UNIVERSITY OF SINGAPORE ... of Contents Summary List of Figures List of Tables List of Symbols Chapter Introduction 1.1 1.2 1.3 1.4 Chapter Motivation and Objectives Earlier Work and Contribution of ... index of feature are above the baseline, the higher possibility of the presence of broken rotor bar fault [4][13][18] The STD and M are important measurements of the statistical distribution of...

Ngày tải lên: 26/09/2015, 10:59

... magnitudes of two kinds of faulty motors, where N is the number of the frequency components 1,2, … , The frequency spectrum of the bearing-fault motor has the frequency signatures of the bearing ... row of (3.1.7) represents the magnitudes of frequency signatures of broken rotor bar motor, and the magnitudes of bearing-fault frequency components equal zero 33 Similarly, the third row of (3.1.7) ... information of fault induction motors and electromechanical systems 3.2.2 Definition of Hilbert Transformation Theory of Hilbert Envelope Analysis is the envelope of the absolute value of signatures,...

Ngày tải lên: 30/09/2015, 13:41

... density of steel and 2.3 times the specific heat of copper Additionally, the measuring equipment is needed to detect it Frequency is the repetition rate of vibration per unit of coefficient of thermal ... criticality of the application, the end user must decide what values of Not mentioned Not mentioned Yes, at machine feet, vibration

Ngày tải lên: 26/11/2015, 09:41