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Showing 1 to 20 of 246 for “"pulse width"”.
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Pulse-width and pulse-time modulators
Thesis (M.S.) Massachusetts Institute of Technology. Dept. of Electrical Engineering, 1947.
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Design of high fidelity pulse width modulation inverter
Pulse-width modulation (PWM) is well established in power electronics as a basis for inverters with sinusoidal output voltages. It provides two crucial advantages: high power delivery efficiency and easy digital-to-analog demodulation. Thus PWM can be applied in audio signal processing chain as a …
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Digital Pulse Width Modulation: Analysis, Algorithms, and Applications
When the input to a PWM modulator is a sequence of uniformly spaced samples of the original signal, the resulting uniform-sampling PWM signal has high distortion. It is possible to eliminate the distortion completely by converting the uniform-sampling input sequence into a natural-sampling sequence …
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Optimization of Systems With Pulse-Width-Modulated Control
Made available in DSpace on 2014-12-08T22:23:47Z (GMT). No. of bitstreams: 1 6511810.pdf: 1902352 bytes, checksum: b1b3adcd3bc0f358880ff859dba2af5d (MD5) Previous issue date: 1965
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Linearization of a pulse width modulated power amplifier
… goal of this thesis is to investigate the use of pulse width modulation in a high efficiency integrated CMOS power amplifier for a wireless application. Though high efficiency CMOS power amplifiers exist in academia, the goal of this project is to explore pulse width modulation as a method of …
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A pulse-width-modulated controlled-transformer post regulator
The theory of operation of a controlled transformer is described. A PWM controlled transformer is proposed and implemented in a forward converter to provide post regulation. Experimental results are presented to verify the new control scheme. Overall efficiency of 82%-86% is achieved in a 200khz, …
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Soft-switching techniques for pulse-width-modulated converters
The concept of soft-switching pulse-width-modulated (PWM) technique was proposed aimed at combining the advantages of both the conventional PWM technique and the resonant technique. This work presents four new families of soft-switching PWM converters: the zero-voltage-switched (ZVS) PWM …
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The Application of Microprocessors to Pulse-Width-Modulated Inverters
The introduction gives consideration to the aspects of communication principles, power converters, PWM modulation techniques and the application of LSI intergrated circuits as regards their effect on the design of variable speed AC drives. <br/><br/>Chapter 1 includes background material where …
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Suppression of Noise Effects in Pulse Width Modulated Systems
Made available in DSpace on 2014-12-08T22:23:31Z (GMT). No. of bitstreams: 1 6408439.pdf: 1499591 bytes, checksum: d59356dd518a4a8c85e537d9a7acc4dd (MD5) Previous issue date: 1964
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The application of communication principles to pulse-width modulated inverters
… principles may be usefully applied to pulse-width modulated inverters to increase their useable frequency range, without increasing the switching frequency of the power devices.<br/><br/>The prior-art techniques of reducing harmonic distortion in pulse-width-modulated inverters is …
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An Exploratory Study of Pulse Width and Delta Sigma Modulators
… qualities of Delta-Sigma Modulators (DSM) and Pulse-Width Modulators (PWM). DSM has long been dominant in the Delta Sigma Analog-to-Digital Converter (DSADC) as a noise-shaped quantizer and time discretizer, while PWM, with a similar self oscillating structure, has seen use in Class D Power …
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Full software AC servo controllers with dynamic pulse width modulation
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1999.
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Driver Based Soft Switch for Pulse-Width-Modulated Power Converters
The work in this dissertation presents the first attempt in the literature to propose the concept of "soft switch". The goal of "soft switch" is to develop a standard PWM switch cell with built-in adaptive soft switching capabilities. Just like a regular switch, only one PWM signal is needed to …
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Novel zero-voltage switching techniques for pulse-width-modulated converters
Two new classes of soft switching pulse-width-modulated (PWM) converters, named zero-voltage-switched (ZVS) PWM converters and zero-voltage-transition (ZVT) PWM converters, are proposed. The proposed ZVS-PWM converters combine the merits of conventional PWM and ZVS-QRC techniques. They are capable …
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Switching frequency reduction in pulse-width modulated multilever converters and systems
… by their unique structures. Along with proper Pulse-Width Modulation (PWM) control scheme, they can also provide lower cost, higher performance, lower Electro-Magnetic Interference (EMI), and higher efficiency than the traditional PWM converters. However, switching losses become a serious issue …
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A modified asymmetrical pulse-width modulated series resonant DC/DC converter
… that can offer this, but the asymmetrical pulse-width modulated (APWM) resonant DC/DC converter is a simple topology that operates at a constant frequency and with near-zero voltage switching losses. However, the range of input voltage where high efficiency is maintained is narrow. After a …
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Analog Single Sideband-Pulse Width Modulation Processor for Parametric Acoustic Arrays
… processor which encodes the audio into two Pulse Width Modulated (PWM) signals in quadrature phase and sums them together to produce a Single Sideband (SSB) spectrum around the fundamental frequency of the PWM signals. The two signals are modulated between 8% and 24% duty cycle to maintain a …
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Design and Analysis of Pulse -Width Modulation Techniques for Spectrum Shaping
The ultimate goal of spectrum-shaping technology is to provide the designer with the ability to specify a desired harmonic spectrum and then to realize it using a proper modulation scheme. The results of Pd-PWM and FM-PWM bring us one step closer to understanding how to meet this goal.
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High-resolution Digital Pulse width Modulation Techniques for Digitally Controlled Power Supplies
L'abstract è presente nell'allegato / the abstract is in the attachment
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Controlling the Vienna rectifier using a simplified space vector pulse width modulation technique
In this thesis, a simplified Space-Vector Pulse-Width-Modulation (SVPWM) technique for the Vienna rectifier is introduced to reduce the computational burden, the switching losses and the Total-Harmonic-Distortion (THD). Furthermore, the robustness of this modulation technique is tested under …
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