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Full-Text Articles in Engineering
A Soft-Switched Three-Port Dc-Dc Converter For A Pv/ Battery System, Mohamedelfatih Dosa
A Soft-Switched Three-Port Dc-Dc Converter For A Pv/ Battery System, Mohamedelfatih Dosa
All Graduate Theses, Dissertations, and Other Capstone Projects
This thesis proposed a soft-switched three-port bidirectional DC-DC converter for managing the power flow of a photovoltaic (PV) and battery system. The proposed converter consists of three ports connected to a PV panel, battery, and load. These three ports are interfaced through the high-frequency transformer and use phase-shift control to achieve soft-switching for all converter switches. Compared with the traditional multiport converters, the proposed three-port converter uses the least number of power switches, and zero-voltage switching (ZVS). Simulation and experimental results validate the design and effectiveness of soft switching and power flow control. The converter can work in different scenarios …
Analysis Of Three-Phase Rectifier Via Three Different Control Methods And Switch Power Loss Comparison, Yichao Wang
Analysis Of Three-Phase Rectifier Via Three Different Control Methods And Switch Power Loss Comparison, Yichao Wang
All Graduate Theses, Dissertations, and Other Capstone Projects
Traditional uncontrolled or phase-controlled rectifiers have the defects of lower power factor and nontrivial higher harmonics which causes the low efficiency of power, bad power quality, and so on. However, PWM rectifiers overcome the drawbacks mentioned above. They reduce the higher harmonics yielding better sinusoidal current on the grid side, achieve unity power factor and bidirectional power flow, and have better dynamic performance. So, it is favored more by academia and widely applied in high-performance power electronics devices. In this paper, the PWM rectifier is analyzed and a comparison of the switch loss on three-phase rectifier using three different control …
Implementation Of Model-Free Adaptive Power Flow Control For Dual-Active-Bridge-Based Ac-Dc Converters, Qinghang Shen
Implementation Of Model-Free Adaptive Power Flow Control For Dual-Active-Bridge-Based Ac-Dc Converters, Qinghang Shen
All Graduate Theses, Dissertations, and Other Capstone Projects
With the rising energy consumption and environment destruction problems worldwide, the development of renewable energy and energy recapture methods to improve the energy utilization rate has become more important as two of the most efficient processes to solve those problems. Bidirectional AC/DC converter and its modulation strategies are widely used as the essential part of implementing bidirectional power conversion between power grid and energy storage systems. To improve the efficiency and accuracy of the power conversion within AC/DC converters, a stable, robust power flow control system with quick response and disturbance rejection ability is desired. This thesis proposes a model-free …
A Wavelet Transform Module For A Speech Recognition Virtual Machine, Euisung Kim
A Wavelet Transform Module For A Speech Recognition Virtual Machine, Euisung Kim
All Graduate Theses, Dissertations, and Other Capstone Projects
This work explores the trade-offs between time and frequency information during the feature extraction process of an automatic speech recognition (ASR) system using wavelet transform (WT) features instead of Mel-frequency cepstral coefficients (MFCCs) and the benefits of combining the WTs and the MFCCs as inputs to an ASR system. A virtual machine from the Speech Recognition Virtual Kitchen resource (www.speechkitchen.org) is used as the context for implementing a wavelet signal processing module in a speech recognition system. Contributions include a comparison of MFCCs and WT features on small and large vocabulary tasks, application of combined MFCC and WT features on …