A white LED boost IC for backlight of TFTLCD based on a current-limited pulse-width modulation

This study is devoted to the consideration of a method for assessing the stability of systems with pulse-width modulation, based on the linearization of its equivalent system with pulse-width modulation. An approximate study of the dynamic modes of operation of systems with pulse-width modulation, taking into account the stability for the system of automatic control of the supply current of electromagnets under the conditions of external and internal interference, is carried out. Variants of execution of schemes of pulse-width regulators for the power supply of an electromagnet based on a unipolar and bipolar element with pulse-width modulation are presented. The possibility of linearization of systems with pulse-width modulation for the subsequent detailed assessment of the stability of such systems is shown. The prospects of using functional differential equations for stability analysis of automatic systems with pulse-width modulation are shown. The frequency characteristics of an equivalent pulse system are analyzed using the example of a current stabilization system of high-power electromagnets with a pulse-width regulator, taking into account the replacement of the latitude modulation by the amplitude one. Based on the analysis of the resulting transfer function, which is a stable linearized equivalent open system, the ways of evaluating the stability of the original system with pulse-width modulation using the Nyquist stability criterion are proposed. The conclusion is made about the advantage of a system with PWM, in relation to a system with AIM, in terms of stability, and recommendations are given for the use of the obtained data in the analysis oftransients in such systems.

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Comparative evaluation of control laws based on pulse-width modulation and on hysteresis: application on a current-injection-based three-phase rectifier

Canadian Journal of Electrical and Computer Engineering ◽

10.1109/cjece.2005.1541754 ◽

2005 ◽

Vol 30 (4) ◽

pp. 215-223 ◽

Cited By ~ 2

Author(s):

H. Kanaan ◽

K. Al-Haddad

Keyword(s):

Comparative Evaluation ◽

Pulse Width ◽

Pulse Width Modulation ◽

Current Injection ◽

Control Laws ◽

Three Phase ◽

A Current

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Control of Circulating Current for Direct-Parallel Connected PWM Inverters

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.756-759.612 ◽

2013 ◽

Vol 756-759 ◽

pp. 612-617

Author(s):

Chun Xue Wen ◽

Kun Kun Fang

Keyword(s):

Pulse Width ◽

Pulse Width Modulation ◽

Operation Time ◽

Maximum Power ◽

Parallel Structure ◽

Space Vector ◽

Circulating Current ◽

Simulation Results ◽

A Current

It can not only make the system more flexibly, but also can make the maximum power higher by using the direct-parallel connected inverters. However, when grid-connected inverters operate in direct-parallel structure, it may lead to potential circulating current. So its important to inhibit circulating current. Its found that the circulating current can be suppressed by controlling the operation time of zero vectors during every PWM cycle of space vector pulse width modulation (SVPWM). Meanwhile, we can add a current-average loop to the system so as to make the circulating current smaller. Simulation results in MATLAB are presented to prove the effectiveness of this method in this paper.

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A Study on the Working Performance of Dimming Methods for Single- and Multichip Power LEDs

International Journal of Photoenergy ◽

10.1155/2012/513768 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

İsmail Kıyak

Keyword(s):

Pulse Width ◽

Energy Savings ◽

Pulse Width Modulation ◽

Low Power Consumption ◽

Passive Cooling ◽

Multichip Module ◽

Light Emitting ◽

Current Variation ◽

Working Performance ◽

A Current

Light emitting diodes (LEDs) have many positive features, such as long life, low power consumption, and high luminous efficacy. Consequently, they are very attractive for use in many applications. Also, the use of LEDs ensures energy savings. Power LEDs have increasingly been used for general lighting via multichip module technology. The output of power LEDs should be controlled to obtain life and illuminance values in catalog. In this study, the effects of different dimming methods are investigated for single-and multichip LEDs. To achieve this aim, pulse width modulation (PWM) and current variation (CV) dimming methods are applied to single and multichip power LEDs during ten stages of dimming. A current-regulated DC source is used for current variation (CV) dimming, and a driver designed by the researcher is used for pulse width modulation (PWM) dimming. Moreover, all of the applications are made for active and passive cooling. Finally, the results are compared.

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A current regulated pulse width modulation method with new series resonant inverter

10.1109/ias.1989.96771 ◽

2003 ◽

Author(s):

Sun-Soon Park ◽

Gyu-Hyeong Cho

Keyword(s):

Pulse Width ◽

Pulse Width Modulation ◽

Modulation Method ◽

Resonant Inverter ◽

Series Resonant ◽

Series Resonant Inverter ◽

A Current

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The 1-Bit Instrument

Journal of Sound and Music in Games ◽

10.1525/jsmg.2020.1.1.44 ◽

2020 ◽

Vol 1 (1) ◽

pp. 44-74

Author(s):

Blake Troise

Keyword(s):

Pulse Width ◽

Pulse Width Modulation ◽

Interleaving Techniques ◽

Sonic Environment

The 1-bit sonic environment (perhaps most famously musically employed on the ZX Spectrum) is defined by extreme limitation. Yet, belying these restrictions, there is a surprisingly expressive instrumental versatility. This article explores the theory behind the primary, idiosyncratically 1-bit techniques available to the composer-programmer, those that are essential when designing “instruments” in 1-bit environments. These techniques include pulse width modulation for timbral manipulation and means of generating virtual polyphony in software, such as the pin pulse and pulse interleaving techniques. These methodologies are considered in respect to their compositional implications and instrumental applications.

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