Author: Fariborz MusaviPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Investigation of High Performance Single-phase Solutions for AC-DC Power Factor Corrected Boost Converters
Author: Fariborz MusaviInvestigation of Power Factor Correction in Single Phase AC-DC Converters
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
An ac to dc converter is an integral part of any power supply unit used in the all electronic equipments. These electronic equipments form a major part of load on the utility. Generally, to convert line frequency ac to dc, a line frequency diode bridge rectifier is used. To reduce the ripple in the dc output voltage, a large capacitor is used at the rectifier output. But due to this large capacitor, the current drawn by this converter is peaky in nature. This input current is rich in low order harmonics. Also, as power electronics equipments are increasingly being used in power conversion, they inject low order harmonics into the utility. Due to the presence of these harmonics, the total harmonic distortion is high and the input power factor is poor. Because of the problems associated with low power factor and harmonics, utilities will enforce harmonic standards and guidelines, which will limit the amount of current distortion allowed into the utility, and thus the simple diode rectifier may not be in use. So, there is a need to achieve rectification at close to unity power factor and low input current distortion. Initially, power factor correction schemes have been implemented mainly for heavy industrial loads like induction motors, induction heating furnaces etc., which forms a major part of lagging power factor load. Hence, PFC is becoming an important aspect even for low power application electronic equipments. There are two types of PFC"s. 1) Passive PFC, 2) Active PFC. The active PFC is further classified into low-frequency and high-frequency active PFC depending on the switching frequency. Different techniques in passive PFC and active PFC are presented here. Among these PFC"s, we will get better power factor by using high-frequency active PFC circuit. Any DC-DC converters can be used for this purpose, if a suitable control method is used to shape its input current or if it has inherent PFC properties. The DC-DC converters can operate in Continuous Inductor C
A New High-Efficiency Single- Stage AC/DC Converter with Power Factor Correction
Author: 王任浩Stability of Different Types of Power Factor Correction
Author: Reham Haroun MohamedPublisher: LAP Lambert Academic Publishing
ISBN: 9783659115455
Category :
Languages : en
Pages : 184
Book Description
Single phase high power factor rectification is the most frequently accomplished using a boost converter. The input current shaping approach results in low line currents harmonic distortion and a power factor close to unity at the interface between the ac line and the rectifier. Various techniques are available for active current shaping, average current mode control, nonlinear control and one cycle control. Most of them are now supported by dedicated integrated circuits. Average-current-mode control is the regular control where the inductor current is forced to follow the input voltage. Recently nonlinear phenomena have been obvious in AC/DC converters which results in unstable regime such as period doubling and chaos. During these operating regimes, the input current distorts and therefore, breaks the operation of PFC converters. In this book, a study for stability for the three practical controls of boost PFC converter is introduced. Each technique has been tested to determine the practical limitation for stable regions. Design guidelines are made clear for stable operation in the examined control techniques. Experimental results confirm simulation with good matching.
Soft Switching for Improving the Efficiency and Power Density of a Single-phase Converter with Power Factor Correction
Author: Tine KonjedicPublisher:
ISBN:
Category :
Languages : en
Pages : 169
Book Description
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.
A Single Stage Power Factor Corrected AC/DC Converter
Author: Matteo DanieleA Single Stage Full Bridge Power Factor Corrected AC/DC Converter
Author: Nasser IsmailPower Electronics and Renewable Energy Systems
Author: C. KamalakannanPublisher: Springer
ISBN: 8132221192
Category : Technology & Engineering
Languages : en
Pages : 1546
Book Description
The book is a collection of high-quality peer-reviewed research papers presented in the Proceedings of International Conference on Power Electronics and Renewable Energy Systems (ICPERES 2014) held at Rajalakshmi Engineering College, Chennai, India. These research papers provide the latest developments in the broad area of Power Electronics and Renewable Energy. The book discusses wide variety of industrial, engineering and scientific applications of the emerging techniques. It presents invited papers from the inventors/originators of new applications and advanced technologies.
Second Harmonic Current Reduction Techniques for Single-Phase Power Electronics Converter Systems
Author: Xinbo RuanPublisher: Springer Nature
ISBN: 9811915474
Category : Technology & Engineering
Languages : en
Pages : 304
Book Description
Two-stage single-phase converters, including two-stage single-phase dc-ac inverters and two-stage single-phase PFC converters, are interfacing power converters between dc and ac voltage/current sources, which have been widely applied for dc-ac and ac-dc power conversion. For the two-stage single-phase converter, the ac-side power pulsates at twice the ac voltage frequency, resulting in second harmonic current (SHC) which might flow into the dc-dc converter, the dc voltage source, and dc load. This book clarifies the generation, propagation, and side-effects of this SHC and proposes the SHC reduction control schemes for the dc-dc converter, with different topologies and/or different operating modes, in the single-phase converter. On this basis, the second harmonic current compensator (SHCC) is proposed to compensate the SHC, significantly reducing the dc bus capacitance. In doing so, the electrolytic capacitors, with short lifetimes, are removed from the two-stage single-phase converter, leading to extended system lifetime and enhanced system stability. For having flawless SHC compensation performance, the port-current control schemes are proposed for the SHCC. Additionally, the stability analysis is carried out for the two-stage single-phase converter with the addition of SHCC. This book is a monograph combining theoretical analysis and engineering design, which could not only be a reference book for master students, Ph.D. students, and teachers majoring in power electronics but also be a handbook for the electrical engineers working on the research and development of LED drivers, EV on-board chargers, railway auxiliary power supplies, aviation power supplies, renewable energy generation systems, etc.
Smart Buildings Digitalization
Author: O.V. Gnana SwathikaPublisher: CRC Press
ISBN: 1000537935
Category : Computers
Languages : en
Pages : 363
Book Description
This book explains the concept of data centers, including data collection, public parking systems, smart metering, and sanitizer dispensers. Electric urban transport systems and effective electric distribution in smart cities are discussed as well. The extensive role of power electronics in smart building applications, such as electric vehicles, rooftop terracing, and renewable energy integration, is included. Case studies on automation in smart homes and commercial and official buildings are elaborated. This book describes the complete implication of smart buildings via industrial, commercial, and community platforms. FEATURES Systematically defines energy-efficient buildings employing power consumption optimization techniques with the inclusion of renewable energy sources Covers data centers and cybersecurity with excellent data storage features for smart buildings Includes systematic and detailed strategies for building air-conditioning and lighting Details smart building security propulsion This book is aimed at graduate students, researchers, and professionals in building systems engineering, architectural engineering, and electrical engineering.