Download or read book An Investigation of Matrix Converter Losses and Soft Switching Techniques written by Michael Bland and published by . This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Investigation of Matrix Converter Losses and Soft Switching Techniques written by Michael Bland (PhD.) and published by . This book was released on 2003 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Analysis and Design of Matrix Converters for Adjustable Speed Drives and Distributed Power Sources written by Han Ju Cha and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Recently, matrix converter has received considerable interest as a viable alternative to the conventional back-to-back PWM (Pulse Width Modulation) converter in the ac/ac conversion. This direct ac/ac converter provides some attractive characteristics such as: inherent four-quadrant operation; absence of bulky dc-link electrolytic capacitors; clean input power characteristics and increased power density. However, industrial application of the converter is still limited because of some practical issues such as common mode voltage effects, high susceptibility to input power disturbances and low voltage transfer ratio. This dissertation proposes several new matrix converter topologies together with control strategies to provide a solution about the above issues. In this dissertation, a new modulation method which reduces the common mode voltage at the matrix converter is first proposed. The new method utilizes the proper zero vector selection and placement within a sampling period and results in the reduction of the common mode voltage, square rms of ripple components of input current and switching losses. Due to the absence of a dc-link, matrix converter powered ac drivers suffer from input voltage disturbances. This dissertation proposes a new ride-through approach to improve robustness for input voltage disturbances. The conventional matrix converter is modified with the addition of ride-through module and the add-on module provides ride-through capability for matrix converter fed adjustable speed drivers. In order to increase the inherent low voltage transfer ratio of the matrix converter, a new three-phase high-frequency link matrix converter is proposed, where a dual bridge matrix converter is modified by adding a high-frequency transformer into dc-link. The new converter provides flexible voltage transfer ratio and galvanic isolation between input and output ac sources. Finally, the matrix converter concept is extended to dc/ac conversion from ac/ac conversion. The new dc/ac direct converter consists of soft switching full bridge dc/dc converter and three phase voltage source inverter without dc link capacitors. Both converters are synchronized for zero current/voltage switching and result in higher efficiency and lower EMI (Electro Magnetic Interference) throughout the whole load range. Analysis, design example and experimental results are detailed for each proposed topology.

Download or read book Design and Control of Matrix Converters written by Anindya Dasgupta and published by Springer. This book was released on 2017-03-30 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes two target applications for synchronous systems: regulated 3-phase voltage supply and voltage sag mitigation. It presents a detailed design procedure for converter switches and filters considering all steady-state, commutation and dynamic requirements. This work has evolved from previously published research by the authors, which in turn is part of a larger effort to expand the application domain of matrix converters to power systems. The objectives of the work have been categorized into the following: developing a dynamic model that provides adequate design insights; designing filters; and devising a control scheme. The low frequency dynamic model is first analyzed for regulated voltage supplies assuming balanced system. The system is modeled relative to a synchronous rotating (dq) frame linearized around an operating point. The input–output variables are related by non-diagonal transfer function matrices. Individual transfer function sub-matrices are sequentially investigated and it is shown that, depending on the input power, input voltage and filter parameters, the appearance of a set of right half zeros is possible. The book then considers filter design, as well as general issues like ripple attenuation, regulation, reactive current loading, and filter losses. The book also addresses additional constraints that may be imposed by dynamic requirements and commutation. In the third stage, voltage controller design is detailed for a 3-phase regulated voltage supply. In dq domain, output voltage control represents a multivariable control problem. This is reduced to a single variable control problem while retaining all possible right half zeros, thereby preserving the internal stability of the system. Consequently, the standard single variable control design technique has been used to design a controller. The analytically predicted dynamic response has been verified by experimental results. It was possible to operate the system beyond the critical power boundary where the right half zeros emerge. Lastly, the developed control approach has been extended to voltage sag mitigation with adequate modifications. A 3-wire linear load and both symmetrical and asymmetrical voltage sags have been considered. Experimentally obtained response time for sag mitigation was found to be less than the power supply holdup time of most of the sensitive equipment. This book will be useful to both researchers and graduate students.

Download or read book CIEP written by and published by . This book was released on 2000 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dissertation Abstracts International written by and published by . This book was released on 2007 with total page 960 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Power Electronics written by Fang Lin Luo and published by CRC Press. This book was released on 2018-01-02 with total page 671 pages. Available in PDF, EPUB and Kindle. Book excerpt: Power Electronics is a large size technology, mainly covering four categories: the AC/DC rectifiers, DC/DC converters, DC/AC inverters, and AC/AC converters. This book offers approximately 100 novel topologies of all four. The applications are used in sustainable energy generation areas, such as distributed generation (DG), micro-grid (MG), smart grid (SG) systems, and electrical vehicles (EV). With case studies from GE, AEG, Simplatroll Ltd, and Chinese Power Manufacturing Co., the reader will be exposed to practical applications in industry and real-world settings. This new edition features an entirely new chapter on best switching angles to obtain lowest THD for multilevel DC/AC inverters. Additionally, all chapters have been updated and include homework problems throughout.

Download or read book Soft Switching for Improving the Efficiency and Power Density of a Single phase Converter with Power Factor Correction written by Tine Konjedic and published by . This book was released on 2015 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis investigates the possibilities for increasing the power conversion efficiency and power density of a single-phase single-stage AC-DC converter with power factor correction capability. Initially, the limitations are investigated for simultaneous increase of power density and efficiency in hard switched bidirectional converters. The switching frequency dependent turn-on losses of the transistors have been identified as the main limiting factor. In order to avoid the increase in total power losses with increasing the switching frequency, a control approach is proposed for achieving zero voltage switching transitions within the entire operating range of a bidirectional converter that utilizes power transistors in a bridge structure. This approach is based on operation in the discontinuous conduction mode with a variable switching frequency. Operation in the discontinuous conduction mode ensures the necessary reversed current that naturally discharges the parasitic output capacitance of the transistor and thus allows this transistor to be turned on at zero voltage. On the other hand, the varying switching frequency ensures that the converter operates close to the zero voltage switching boundary, which is defined as the minimum required current ripple at which zero voltage switching can be maintained. Operation with the minimum required current ripple is desirable as it generates the lowest magnetic core losses and conduction losses within the power circuit. The performance and effectiveness of the investigated approach were initially verified in a bidirectional DC-DC converter. A reliable zero voltage switching was confirmed over the entire operating range of a bidirectional DC-DC converter, as well as the absence of the reverse recovery effect and the unwanted turn-on of the synchronous transistor. In order to justify its usage and demonstrate its superior performance, the proposed zero voltage switching technique was compared with a conventional continuous conduction mode operation which is characterized by hard switching commutations. After successful verification and implementation in a bidirectional DC-DC converter, the investigated zero voltage switching approach was adapted for usage in an interleaved DC-AC converter with power factor correction capability. Comprehensive analysis of the converter's operation in discontinuous conduction mode with a variable switching frequency was performed in order to derive its power loss model. The latter facilitated the design process of the converter's power circuit. A systematic approach for selecting the converter's power components has been used while targeting for an extremely high power conversion efficiency over a wide operating range and a low volume design of the converter. The final result of the investigations performed within the scope of this thesis is the interleaved AC-DC converter with power factor correction capability. Utilization of interleaving allows for increasing the converter's power processing capability, reduces the conducted differential mode noise and shrinks the range within which the switching frequency has to vary. The proposed zero voltage switching control approach was entirely implemented within a digital signal controller and does not require any additional components within the converter's circuit. The experimental results have confirmed highly efficient operation over a wide range of operating powers. A peak efficiency of 98.4 % has been achieved at the output power of 1100 W, while the efficiency is maintained above 97 % over the entire range of output powers between 200 W and 3050 W.

Download or read book Energy Efficiency in Electric Motors Drives Power Converters and Related Systems written by Mario Marchesoni and published by MDPI. This book was released on 2020-06-25 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: Today, there is a great deal of attention focused on sustainable growth worldwide. The increase in efficiency in the use of energy may even, in this historical moment, bring greater benefit than the use of renewable energies. Electricity appears to be the most sustainable of energies and the most promising hope for a planet capable of growing without compromising its own health and that of its inhabitants. Power electronics and electrical drives are the key technologies that will allow energy savings through the reduction of energy losses in many applications. This Special Issue has collected several scientific contributions related to energy efficiency in electrical equipment. Some articles are dedicated to the use and optimization of permanent magnet motors, which allow obtaining the highest level of efficiency. Most of the contributions describe the energy improvements that can be achieved with power electronics and the use of suitable control techniques. Last but not least, some articles describe interesting solutions for hybrid vehicles, which were created mainly to save energy in the smartest way possible.

Download or read book Proceedings of the 4th International Conference on Electrical and Information Technologies for Rail Transportation EITRT 2019 written by Limin Jia and published by Springer Nature. This book was released on 2020-04-07 with total page 869 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reflects the latest research trends, methods and experimental results in the field of electrical and information technologies for rail transportation, which covers abundant state-of-the-art research theories and ideas. As a vital field of research that is highly relevant to current developments in a number of technological domains, the subjects it covered include intelligent computing, information processing, Communication Technology, Automatic Control, etc. The objective of the proceedings is to provide a major interdisciplinary forum for researchers, engineers, academicians as well as industrial professionals to present the most innovative research and development in the field of rail transportation electrical and information technologies. Engineers and researchers in academia, industry, and the government will also explore an insight view of the solutions that combine ideas from multiple disciplines in this field. The volumes serve as an excellent reference work for researchers and graduate students working on rail transportation, electrical and information technologies.

Download or read book Auxiliary Circuit assisted Soft Switching Techniques and Their Application to Power Converters written by Ranganathan Gurunathan and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The need to incorporate significant improvements in power supplies is driven by customer demands, industry requirements and regulatory standards. For reduction in size and weight, it is imperative to process the power at a higher switching frequency. High frequency processing of power requires soft switching techniques to reduce the switching losses. Many soft switching techniques are reported in the literature to enhance the high frequency operation of power supplies. This thesis proposes novel high frequency, auxiliary circuit assisted, (a) soft-switched boost converters and their application to DC-to- DC converters and AC-to-DC front-end power factor corrected converters; and (b) zero-voltage switching (ZVS) dc link DC-to-AC inverters. In auxiliary circuit assisted soft transition converters, the auxiliary circuit processes the power during switching transitions, creating a soft transition path. In most of the proposed converters in the literature, the auxiliary circuit suffers from severe switching losses and switching stress. Discontinuous current operation of the auxiliary circuit results in parasitic oscillations between the switch capacitance and the resonant inductors increasing the stress on the devices. A zero-current switching (ZCS) auxiliary circuit and ZVS auxiliary circuit are proposed in this thesis to achieve soft transitions for the main circuit. A ZCS auxiliary circuit assisted soft transition boost converter is proposed. Operating intervals of the proposed technique in various intervals of operation are analyzed. Design constraints and considerations are discussed. A 300 W dc-to-dc boost converter and a 600 W, ac-to-dc power factor correction front-end boost converter prototype models are built in the laboratory. The experimental results confirm the theory. The resonant inductor used in the auxiliary circuit is coupled weakly to the boost inductor. Although parasitic oscillations are reduced due to the coupling, they are not completely eliminated. Hence, RC snubbers are required to suppress the oscillations. A ZVS auxiliary circuit assisted soft transition boost converter is also presented. Operating intervals of the proposed converter in various intervals of operation are analyzed. As all the parasitic elements in the circuit are accounted, parasitic oscillations are eliminated. A 300 W dc-to-dc converter operating at 250 kHz is built in the laboratory to verify the theory. A modified gating scheme to utilize the soft switching auxiliary circuit in the main power processing is also proposed. A 600 W, 100 kHz, 380 V dc, operating with universal input line voltage, ac-to-dc power factor corrected (PFC) boost converter is built using the proposed technique with modified gating algorithm. Large signal analysis to analyze the soft switching characteristics of the proposed technique during load and input voltage transients is also presented. PSPICE simulation results are presented to verify the theory. The proposed converter maintains soft switching during load and input voltage transients. The proposed auxiliary network is also extended to a family of pulse width modulated (PWM) converters. A two-switch soft switching boost converter is derived from the proposed converter. By integrating the proposed auxiliary network with a full bridge inverter, a ZVS dc link voltage source inverter (VSI) is obtained. Operating intervals of the proposed inverter in various intervals of operation for the forward power flow and reverse power flow are presented. A modified unipolar switching scheme to achieve ZVS during reverse power flow is also presented. The voltage stress on the VSI is clamped to the dc bus voltage in the proposed converter. The conduction losses are reduced as compared to other soft switching converters in the literature. As the proposed technique requires synchronized PWM operation, sine-ramp modulated PWM signals are used. Experimental results from a 120 V, 60 Hz, 300 VA, single phase VSI switching at 50 kHz are presented to verify the theory.

Download or read book Index to Theses with Abstracts Accepted for Higher Degrees by the Universities of Great Britain and Ireland and the Council for National Academic Awards written by and published by . This book was released on 2007 with total page 676 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Renewable Energy and the Environment written by Md. Rabiul Islam and published by Springer. This book was released on 2017-12-16 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses a number of important topical technical and non-technical issues related to the global energy, environment and socio-economic developments for professionals and students directly and indirectly involved in the relevant fields. It shows how renewable energy offers solutions to mitigate energy demand and helps achieve a clean environment, and also addresses the lack of a clear vision in the development of technology and a policy to reach the mandatory global renewable energy targets to reduce greenhouse gas emissions and stimulate socio-economic development. The book is structured in such a way that it provides a consistent compilation of fundamental theories, a compendium of current research and development activities as well as new directions to overcome critical limitations; future technologies for power grids and their control, stability and reliability are also presented.

Download or read book Analysis Optimization and Control of Grid Interfaced Matrix Based Isolated AC DC Converters written by Jaydeep Saha and published by Springer Nature. This book was released on 2022-11-05 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents novel contributions in the development of solid-state-transformer (SST) technology both for medium-voltage (MV) and low-voltage (LV) utility grid interfaces, which can potentially augment the grid modernization process in the evolving power system paradigm. For the MV interface, a single-stage AC-DC SST submodule topology has been proposed, and its modulation and soft-switching possibilities are analysed, experimentally validated and adequately benchmarked. A control scheme with power balance capability among submodules is developed for MV grid-connected single-stage AC-DC SST for smooth operation under inevitable parameter drift scenario, and experimental validation shows excellent performance under drastic load change conditions. A novel machine learning-aided multi-objective design optimization framework for grid-connected SST is developed and experimentally validated, which equips a power electronics design engineer with meagre computational resources to find out the most optimal SST design in a convenient time-frame. This book has also contributed towards the development of dual-active-bridge (DAB)-type and non-DAB-type LV grid-interfaced isolated AC-DC converters by providing solutions to specific topology and modulation-related shortcomings in these two types of topologies. A comprehensive comparison of the DAB and non-DAB-type LVAC-LVDC converters reveals the superiority of DAB-type conversion strategy.

Download or read book Loss Analysis and Design of a Novel Soft Switching Converter written by 何永財 and published by Open Dissertation Press. This book was released on 2017-01-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Loss Analysis and Design of a Novel Soft Switching Converter" by 何永財, Wing-choi, Ho, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. DOI: 10.5353/th_b3123702 Subjects: Electric current converters - Design

Download or read book Power Electronics and Motor Drives written by Bimal K. Bose and published by Academic Press. This book was released on 2020-11-13 with total page 1110 pages. Available in PDF, EPUB and Kindle. Book excerpt: Power Electronics and Motor Drives: Advances and Trends, Second Edition is the perfect resource to keep the electrical engineer up-to-speed on the latest advancements in technologies, equipment and applications. Carefully structured to include both traditional topics for entry-level and more advanced applications for the experienced engineer, this reference sheds light on the rapidly growing field of power electronic operations. New content covers converters, machine models and new control methods such as fuzzy logic and neural network control. This reference will help engineers further understand recent technologies and gain practical understanding with its inclusion of many industrial applications. Further supported by a glossary per chapter, this book gives engineers and researchers a critical reference to learn from real-world examples and make future decisions on power electronic technology and applications. - Provides many practical examples of industrial applications - Updates on the newest electronic topics with content added on fuzzy logic and neural networks - Presents information from an expert with decades of research and industrial experience

Download or read book Design and Control of Power Converters 2020 written by Manuel Arias and published by MDPI. This book was released on 2021-06-04 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, nine papers focusing on different fields of power electronics are gathered, all of which are in line with the present trends in research and industry. Given the generality of the Special Issue, the covered topics range from electrothermal models and losses models in semiconductors and magnetics to converters used in high-power applications. In this last case, the papers address specific problems such as the distortion due to zero-current detection or fault investigation using the fast Fourier transform, all being focused on analyzing the topologies of high-power high-density applications, such as the dual active bridge or the H-bridge multilevel inverter. All the papers provide enough insight in the analyzed issues to be used as the starting point of any research. Experimental or simulation results are presented to validate and help with the understanding of the proposed ideas. To summarize, this book will help the reader to solve specific problems in industrial equipment or to increase their knowledge in specific fields.