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Showing 1 to 20 of 24 for “"PWM Converters"”.
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Soft-switching techniques for high-power PWM converters
… several soft-switching topologies for high power PWM converters. These new topologies achieve soft-switching functions with minimum increase of device voltage/current stresses and converter circulating energy, and thus have advantages over conventional techniques in efficiency, power density, …
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Modeling and control of three-phase PWM converters
… models are developed for major three-phase PWM converters. The models are correct for the case when the voltage sources or capacitors with nonzero parasitic resistances are placed across the converter dc port or ac terminals. The effects of the parasitic resistances are described by …
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Modeling and Control of Parallel Three-Phase PWM Converters
… of parallel three-phase pulse-width modulated (PWM) converters. The converters include three-phase boost rectifiers, voltage source inverters, buck rectifiers and current source inverters. The averaging of the parallel converters is performed based on a generic functional switching unit, which …
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Average current-mode control and charge control for PWM converters
Two control schemes for PWM converters, average current-mode (ACM) control and charge control, are studied in this dissertation. The small-signal models are derived for continuous-conduction mode PWM converters employing these two controls. Sampled-data modeling is applied to the current loop …
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Active-clamp PWM converters: design-oriented analysis and small-signal characterization
… an active clamp (ACL) circuit in high-frequency PWM converters with an electrical isolation. Existing design guidelines and design trade-offs for the ACL in forward and flyback converters are reviewed, and specific properties of both circuits that are caused by the ACL are highlighted. Based on …
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Application of High-Power Snubberless Semiconductor Switches in High-Frequency PWM Converters
… to perform high frequency switching. Low-power converters, such as computer power supplies and low horsepower motor drives, have employed high-frequency switching for years and have benefited from very nice output waveforms, good control dynamic performance, and many other advantages compared to …
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Unified Large And Small Signal Discrete-space Modeling For Pwm Converters In Ccm
… a Unified Discrete State-Space Model for power converters in CCM is presented. Two main approaches to arriving at the discrete model are used. The first approach involves an impulse function approximation of the duty cycle modulations of the converter switches , and this approach results in a …
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Zero-voltage switched resonant and PWM converters: design-oriented analysis and performance evaluation
… is developed to optimize implementation of the converters in terms of efficiency. Efficiency optimization requires minimizing the circulating currents which are directly proportional to the reactive energy required by the resonant tank. The comparison of the different converters is based on the …
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Nonlinear Analysis and Control of Standalone, Parallel DC-DC, and Parallel Multi-Phase PWM Converters
… a stable design. Conventional analyses of power converters are based on averaged models, which ignore the fast-scale instability and analyze the stability on a reduced-order manifold. As such, validity of the averaged models varies with the switching frequency even for the same topological …
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Soft-switching techniques for pulse-width-modulated converters
… 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 converters, …
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Novel zero-voltage switching techniques for pulse-width-modulated converters
… 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 of …
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Use of IGT/COMFET in zero current quasi resonant converters
… problems associated with IGT/COMFET devices in PWM converters, such as turn off current tailing and latching are largely avoided in a resonant converter. Dynamic saturation loss is identified as the predominant power loss in IGT/COMFET devices for very high frequency resonant operation. Device …
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Three-phase power conversion using soft-switching PWM techniques
… issues related to high-frequency soft-switching PWM three-phase power converters. These are: 1. Analysis, synthesis, and design of three-phase soft-switching PWM power converter topologies 2. Design of input EMI filters for three-phase converters 3. Design of microprocessor controllers for …
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Switching frequency reduction in pulse-width modulated multilever converters and systems
Multilevel converters have attracted a great deal of interest in recent years since they offer a number of advantages in many high voltage and high power applications, such as adjustable speed electric motor drives and power systems through Flexible Alternating Current Transmission Systems (FACTS) …
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Improved Resonant Converters with a Novel Control Strategy for High-Voltage Pulsed Power Supplies
… magnetic volume. For non-isolation topologies, PWM converters can achieve soft switching to increase switching frequency. However, for this application, due to the large voltage regulation range and high voltage transformer nonidealities, it is difficult to optimize PWM converters. Secondary …
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Stability analysis of large-scale power electronics systems
… is verified through stability analysis of PWM converters and a typical power electronics system.
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Small-signal analysis and design of a distributed power system
… power system is composed of conventional PWM converters, the analysis methods can be extended to systems using other converter topologies. The analysis focuses on two important features of a two-stage distributed power system: parallel power modules and cascaded regulators. The …
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State-Trajectory Analysis and Control of LLC Resonant Converters
… time operation capability. However, unlike PWM converters, the control of the LLC resonant converter is much more difficult because of the fast dynamic characteristic of the resonant tank. In some highly dynamic processes like the load transient, start-up, over-load protection and burst …
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Optimal vertical plane booster guidance including pitch dynamics
… several soft-switching topologies for high power PWM converters. These new topologies achieve soft-switching functions with minimum increase of device voltage/current stresses and converter circulating energy, and thus have advantages over conventional techniques in efficiency, power density, …
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Topology investigation of front end DC/DC converter for distributed power system
… density, lower profile and higher efficiency. PWM topologies have been widely used for this application. Unfortunately, hold up time requirement put huge penalties on the performance of these topologies. Also, high switching loss limited the power density achievable for these topologies. Two …
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