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Showing 1 to 8 of 8 for “"variable frequency modulation"”.
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LLC Resonant Converter Based Single-stage Inverter with Multi-resonant Branches
This paper presents a single-stage inverter with variable frequency modulation (VFM) based on LLC resonant converter. And LLC converter is a common topology of dc/dc conversion. LLC resonant converter can achieve high efficiency and soft-switching performance. Since the dc gain curve of the …
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Unified Three-terminal Switch Model for Current Mode Controls
… Since the inductor current ramp, one of state variables influenced by the input voltage and the output voltage, is used in the modulator in current-mode control without any low pass filter, high order harmonics play important role in the feedback control. This is the reason for the difficulty …
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High-Efficiency and High-Frequency Resonant Converter Based Single-Stage Soft-Switching Isolated Inverter Design and Optimization with Gallium-Nitride (GaN)
… capacitor is needed to attenuate the double line frequency from SPWM for two-stage configuration. Therefore, the single-stage approach including an isolated dc-rectified sine stage and a line frequency unfolder is preferable. Since the unfolder circuit is at line frequency being almost lossless, …
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Fully Soft-Switching Modulation Methods for SRC-Unfolding Inverter
… topology. To figure out the reason, basic modulation methods proposed or implied in the literature are summarized and evaluated through circuit simulation software. It turns out each basic modulation method has at least one critical drawback in modulation range, hard switching, and/or high …
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Padrão vocal de reconhecimento específico em Troglodytes musculus (Aves: Passeriformes: Troglodytidae) no Rio de Janeiro
… one is composed of trills of tonal notes with variable frequency modulation. Trills varied mainly in respect to frequency range and duration. Intersyllable interval and syllable duration were the less variable features of trills, while the minimum frequency and the variation of the frequency …
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Stacked-Switched Electrolytic Capacitor-less AC/DC Power Converters
… factor correction. Closed-loop control based on Variable Frequency Modulation (VFM) is used for voltage regulation, and a secondary-side duty modulation strategy minimizes low-frequency ripple, enabling the use of compact, long-life capacitors. Experimental validation on a 1.1kW prototype …
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Current-Mode Control: Modeling and its Digital Application
… control and voltage-mode control is the PWM modulation. The inductor current, one of state variables, is used in the modulator in current-mode control while an external ramp is used in voltage-mode control. The dynamic nonlinearity of current-mode control results in the difficulty of …
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Equivalent Circuit Model for Current Mode Controls and Its Extensions
… model for current-mode control in the frequency domain. A continuous time domain model was recently proposed as a successful model for current-mode control architectures. However, the model was derived by describing function method, which is very arithmetically complicated, not to …