Download or read book Modeling and Control of Three phase Grid connected PV Inverters in the Presence of Grid Faults written by Paresh Vinubhai Patel and published by . This book was released on 2018 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: "A two-stage photovoltaic grid-connected microgrid modeling approach is presented in this work. The purpose of the modeling is the behavior study of the microgrid during the low-voltage event on the grid. A complete mathematical model is discussed for each component of the system. The MPPT of the photovoltaic system is integrated with the boost controller to inject the constant current in the DC-link. The boost converter and the inverter control is implemented using the cascaded PI control. A dual second-order generalized integrator (DSOGI) method is implemented for the sequence extraction. The inverter controller is designed to meet the grid-code requirement of low-voltage ride through (LVRT) and reactive power injection. The simulation model is designed in a MATLAB/PLECS environment, and the controller design is validated by running a low-voltage event on the grid. To observe the interaction of a multiple PV system with the grid, a nonlinear average model of the two-stage grid-connected PV system was designed and validated against the switching model. A low voltage event on the grid was simulated to observe the impact on the multiple PV system. A power quality event of voltage dip during the unbalance voltage on the grid is presented. The implication of the ungrounded system during the low-voltage event is explained. In addition, the importance of grounding and the effect of the line impedance for the why-connected system is described in detail"--Abstract, page iii.

Download or read book Modeling and Simulation of Three Phase Inverter to Investigate Fault Detection in Distribution Systems written by Shiva Prasad Pokharel and published by . This book was released on 2014 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ever increasing integration of distributed generators (DGs) is bringing new challenges to the protection and control of electric power distribution systems. Connections of power electronics (PE) based DGs bring further challenges in detection of disturbance events and distinguishing faults because of the the active current limiting feature of these inverters. Control of PE based DGs has been discussed in literature with different control approaches and algorithms for grid connected and standalone modes of operation. This thesis presents per phase based control of three phase inverter in dq frame of reference. A simulation model is built in PSCAD for the grid connection operation of this inverter using the standard IEEE 13 node test feeder. Performance of the inverter is extensively tested during different types of disturbances: faults, capacitor switching and load switching. Finally, recorded waveforms obtained during such disturbances are analyzed in order to detect and differentiate faults from load and capacitor switching events.

Download or read book Grid Connected PV Inverters written by Jordana Bratt and published by . This book was released on 2011 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: The need for a cleaner environment and the continuous increase in power demands makes renewable energy production like solar and wind increasingly interesting. Energy production using solar energy could be a solution for the ever increasing power demands. This demand overloads the distribution grids as well as the power stations having a negative impact on power quality and availability. One solution to this problem is grid-connected photovoltaic (PV) systems. A PV array has an optimum operating point, known as the maximum power point, which varies according to cell temperature and insulation level and array voltage. A maximum power point tracker (MPPT) is needed to operate the PV array at the optimal point enabling the system to extract the maximum amount of energy available. Once the system is in place it can be either connected to a charge a battery or to the grid through an inverter. This research explores the different methods for modeling a PV array and simulates in Simulink a comprehensivemodel of a PV cell that can be expanded into arrays, modules and panels, allowing the user to edit the PV model based solely on the datasheet parameters. This model is coupled to a DC-DC booster (step up converter). By manipulating the duty cycle of the DC-DC booster the system implements two of the most popular MPPT methods to extract maximum power: Incremental Conductance and Perturb and Observe. The model is then tested under various conditions for different loads, irradiance and temperature comparing it to the values provided by the manufacture's datasheet. The system is then connected to either a Single Phase Inverter or a Three Phase Inverter implemented in Simulink. The final step is the grid synchronization through two proposed methods of NREL: voltage control and current control. Several simulations were performed to make sure the system complied with all IEEE 1547 standards. The overall PV model system has an efficiency of 98.2% with the best performance under the Incremental Conductance algorithm. The inverter model complies with all IEEE 1547 standards varying a maximum of 5% under different testing conditions.

Download or read book Distributed Photovoltaic Grid Transformers written by Hemchandra Madhusudan Shertukde and published by CRC Press. This book was released on 2017-12-19 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt: The demand for alternative energy sources fuels the need for electric power and controls engineers to possess a practical understanding of transformers suitable for solar energy. Meeting that need, Distributed Photovoltaic Grid Transformers begins by explaining the basic theory behind transformers in the solar power arena, and then progresses to describe the development, manufacture, and sale of distributed photovoltaic (PV) grid transformers, which help boost the electric DC voltage (generally at 30 volts) harnessed by a PV panel to a higher level (generally at 115 volts or higher) once it is inverted to the AC voltage form by the inverter circuit. Packed with real-life scenarios and case studies from around the globe, Distributed Photovoltaic Grid Transformers covers the key design, operation, and maintenance aspects of transformers suitable for solar energy. Topics include islanding, voltage flicker, voltage operating range, frequency and power factor variation, and waveform distortion. Multiple homework questions are featured in each chapter. A solutions manual and downloadable content, such as illustrated examples, are available with qualifying course adoption.

Download or read book Control of Power Inverters in Renewable Energy and Smart Grid Integration written by Qing-Chang Zhong and published by John Wiley & Sons. This book was released on 2012-11-16 with total page 407 pages. Available in PDF, EPUB and Kindle. Book excerpt: Integrating renewable energy and other distributed energy sources into smart grids, often via power inverters, is arguably the largest “new frontier” for smart grid advancements. Inverters should be controlled properly so that their integration does not jeopardize the stability and performance of power systems and a solid technical backbone is formed to facilitate other functions and services of smart grids. This unique reference offers systematic treatment of important control problems in power inverters, and different general converter theories. Starting at a basic level, it presents conventional power conversion methodologies and then ‘non-conventional’ methods, with a highly accessible summary of the latest developments in power inverters as well as insight into the grid connection of renewable power. Consisting of four parts – Power Quality Control, Neutral Line Provision, Power Flow Control, and Synchronisation – this book fully demonstrates the integration of control and power electronics. Key features include: the fundamentals of power processing and hardware design innovative control strategies to systematically treat the control of power inverters extensive experimental results for most of the control strategies presented the pioneering work on “synchronverters” which has gained IET Highly Commended Innovation Award Engineers working on inverter design and those at power system utilities can learn how advanced control strategies could improve system performance and work in practice. The book is a useful reference for researchers who are interested in the area of control engineering, power electronics, renewable energy and distributed generation, smart grids, flexible AC transmission systems, and power systems for more-electric aircraft and all-electric ships. This is also a handy text for graduate students and university professors in the areas of electrical power engineering, advanced control engineering, power electronics, renewable energy and smart grid integration.

Download or read book Solar Photovoltaic Power Plants written by Radu-Emil Precup and published by Springer. This book was released on 2019-02-07 with total page 263 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book discusses control and optimization techniques in the broadest sense, covering new theoretical results and the applications of newly developed methods for PV systems. Going beyond classical control techniques, it promotes the use of more efficient control and optimization strategies based on linearized models and purely continuous (or discrete) models. These new strategies not only enhance the performance of the PV systems, but also decrease the cost per kilowatt-hour generated.

Download or read book Modeling techniques and control strategies for inverter dominated microgrids written by Gkountaras, Aris and published by Universitätsverlag der TU Berlin. This book was released on 2017-02-15 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: The character of modern power systems is changing rapidly and inverters are taking over a considerable part of the energy generation. A future purely inverter-based grid could be a viable solution, if its technical feasibility can be first validated. The focus of this work lies on inverter dominated microgrids, which are also mentioned as 'hybrid' in several instances throughout the thesis. Hybrid, as far as the energy input of each generator is concerned. Conventional fossil fuel based generators are connected in parallel to renewable energy sources as well as battery systems. The main contributions of this work comprise of: The analysis of detailed models and control structures of grid inverters, synchronous generators and battery packs and the utilization of these models to formulate control strategies for distributed generators. The developed strategies accomplish objectives in a wide time scale, from maintaining stability during faults and synchronization transients as well as optimizing load flow through communication-free distributed control. Die Struktur der modernen Energieversorgung hat sich in den letzten Jahrzehnten massiv geändert. Dezentrale Generatoren, die auf Wechselrichtern basieren, übernehmen einen großen Teil der Energieerzeugung. Ein ausschließlich wechselrichterbasiertes Netz wäre ein realistischer Ansatz, wenn seine technische Machbarkeit verifiziert werden könnte. Die wichtigste Beiträge dieser Arbeit sind: Die Analyse von Modellen und Regelstrukturen von Netzwechselrichtern, Synchrongeneratoren und Batterieanlagen. Die entwickelten Modelle werden verwendet, um Regelstrategien für dezentrale Generatoren in Mittelspannungsinselnetzen zu formulieren. Die erste Strategie ist eine Synchronisationsmethode für netzbildende Wechselrichter. Zweitens wird die Leistungsaufteilung in Mittelspannungsinselnetzen mittels Droop Regelung analysiert. Weiterhin erfolgt die Untersuchung der transienten Lastaufteilung zwischen netzbildenden Einheiten mit unterschiedlichen Zeitkonstanten. Beim Betrieb mehrerer paralleler Wechselrichter wird der Einfluss der Netzimpedanz auf die transiente Lastaufteilung analysiert. Die dritte entworfene Regelstrategie umfasst die Integration der Sekundärregelung in die Primärregelung. Der Ladezustand von Batterien wird mit der Lastaufteilung gekoppelt, um die Autonomie des Netzes zu stärken. Abschließend wird eine Kurzschlussstrategie für netzbildende und netzspeisende Wechselrichter entwickelt. Ziel der Strategie ist die Maximierung des Kurzschlussstromes. Als zusätzliche Randbedingung soll keine Kommunikation zwischen Generatoren stattfinden.

Download or read book Initial Guidelines on Representation of Grid tied Inverters Under Fault Scenarios written by Javier Hernández-Alvídrez and published by . This book was released on 2018 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work in this thesis focuses on deriving and proposing comprehensive analytical models of grid-tied, dq-controlled inverters (single-phase and three-phase) under balanced and unbalanced fault conditions. Each model derivation relies on reasonable approximations (which were observed under simulation) of the dynamics of the Phase Locked Loop (PLL) and the controller response under fault scenarios. The derived models are: simple, accurate, consistent in format with models of rotating machines, and compatible with typical fault calculation programs. One of the novelties presented in the three-phase analytical model relies on the fact that it can be used not only for balanced faults, but also for unbalanced faults scenarios, where most of the recently proposed models do not behave accurately with respect to the corresponding dynamics under fault conditions. The proposed models also bridge the analytical gap that exists between studies and reports that represent the inverters as limited current sources during fault occurrences.

Download or read book Advanced Technologies for Modeling Optimization and Control of the Future Distribution Grid written by Ningyi Dai and published by Frontiers Media SA. This book was released on 2022-04-20 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Integration of Distributed Generation in the Power System written by Math H. J. Bollen and published by John Wiley & Sons. This book was released on 2011-08-09 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: The integration of new sources of energy like wind power, solar-power, small-scale generation, or combined heat and power in the power grid is something that impacts a lot of stakeholders: network companies (both distribution and transmission), the owners and operators of the DG units, other end-users of the power grid (including normal consumers like you and me) and not in the least policy makers and regulators. There is a lot of misunderstanding about the impact of DG on the power grid, with one side (including mainly some but certainly not all, network companies) claiming that the lights will go out soon, whereas the other side (including some DG operators and large parks of the general public) claiming that there is nothing to worry about and that it's all a conspiracy of the large production companies that want to protect their own interests and keep the electricity price high. The authors are of the strong opinion that this is NOT the way one should approach such an important subject as the integration of new, more environmentally friendly, sources of energy in the power grid. With this book the authors aim to bring some clarity to the debate allowing all stakeholders together to move to a solution. This book will introduce systematic and transparent methods for quantifying the impact of DG on the power grid.

Download or read book Control of Grid connected Three phase Three wire Voltage sourced Inverters Under Voltage Disturbances written by Miguel Andrés Garnica López and published by . This book was released on 2019 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present doctoral thesis focuses on designing control schemes for three-phase three-wire voltage-sourced inverters connected to the grid under voltage disturbances. The research recognizes the large-scale integration of distributed power generation systems into the network and takes advantage of this circumstance to investigate and develop new control strategies in order to provide better support to the modern power grid. As a first contribution, a new algorithm to maximize power delivery capability of the inverter has been developed and experimentally tested under voltage imbalance conditions, i.e., during slight/shallow and deep asymmetrical sags. The algorithm of this control strategy meets grid code requirements, performs active power control, limits the maximum current injected by the inverter, and eliminates active power oscillations. As a result, six different cases of current injection were identified in this work, considering restrictions imposed by grid codes as well as different active-power production scenarios. The second contribution of this research work has provided an experimental analysis of a low-voltage ride-through strategy whose voltage support capability had not been tested when voltage sags occur. This study was performed considering a scenario of multiple grid-connected inverters, different profiles of active power injection, and the equivalent grid impedance seen from the output side of each converter. In the third contribution has been proposed a closed-loop controller for low-power distributed inverters that maximizes the current injection when voltage sag occurs. The control algorithm has been designed to meet grid code requirements and avoid overvoltage in non-faulty phases during grid faults. The controller is responsible for meeting coordinately several objectives and addressing the interactions that appear among them. In the last two chapters, the argument of this doctoral thesis is complemented, the obtained experimental results are globally analyzed, finally, the present research work is concluded.

Download or read book Modeling and control of power converters in weak and unbalanced electric grids written by Just, Hendrik and published by Universitätsverlag der TU Berlin. This book was released on 2021-11-25 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt: Grid converters increasingly affect power system operation due to the increasing share of renewable energy sources and less conventional power plants. This shift in power generation leads to converter-dominated weak grids, which show critical stability phenomena but also enable converters to contribute to grid stability and voltage support. This thesis presents critical parts of converter controls and describes models to assess their characteristics. These models are used to derive design criteria and dedicated stability analysis methods for grid converter controls. Der steigende Anteil an erneuerbaren Energien in den Energieversorgungsnetzen führt zur Verdrängung konventioneller Kraftwerke. Diese Entwicklung lässt umrichterdominierte und schwache Netzabschnitte entstehen, die kritischen Stabilitätsmechanismen unterliegen, allerdings auch ermöglichen, dass Umrichter aktiv zur Netzstützung und Netzstabilität beitragen können. Die vorliegende Arbeit beschreibt kritische Regelungskomponenten der Umrichter und deren Modellierung. Auf Basis der Modelle werden Auslegungskriterien für die Regelungen abgeleitet und dedizierte Stabilitätsanalysemethoden präsentiert.

Download or read book Power Converter of Electric Machines Renewable Energy Systems and Transportation written by Adolfo Dannier and published by MDPI. This book was released on 2021-09-02 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: Power converters and electric machines represent essential components in all fields of electrical engineering. In fact, we are heading towards a future where energy will be more and more electrical: electrical vehicles, electrical motors, renewables, storage systems are now widespread. The ongoing energy transition poses new challenges for interfacing and integrating different power systems. The constraints of space, weight, reliability, performance, and autonomy for the electric system have increased the attention of scientific research in order to find more and more appropriate technological solutions. In this context, power converters and electric machines assume a key role in enabling higher performance of electrical power conversion. Consequently, the design and control of power converters and electric machines shall be developed accordingly to the requirements of the specific application, thus leading to more specialized solutions, with the aim of enhancing the reliability, fault tolerance, and flexibility of the next generation power systems.

Download or read book Integration of Green and Renewable Energy in Electric Power Systems written by Ali Keyhani and published by John Wiley & Sons. This book was released on 2009-12-14 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: A practical, application-oriented text that presents analytical results for the better modeling and control of power converters in the integration of green energy in electric power systems The combined technology of power semiconductor switching devices, pulse width modulation algorithms, and control theories are being further developed along with the performance improvement of power semiconductors and microprocessors so that more efficient, reliable, and cheaper electric energy conversion can be achieved within the next decade. Integration of Green and Renewable Energy in Electric Power Systems covers the principles, analysis, and synthesis of closed loop control of pulse width modulated converters in power electronics systems, with special application emphasis on distributed generation systems and uninterruptible power supplies. The authors present two versions of a documented simulation test bed for homework problems and projects based on Matlab/Simulink, designed to help readers understand the content through simulations. The first consists of a number of problems and projects for classroom teaching convenience and learning. The second is based on the most recent work in control of power converters for the research of practicing engineers and industry researchers. Addresses a combination of the latest developments in control technology of pulse width modulation algorithms and digital control methods Problems and projects have detailed mathematical modeling, control design, solution steps, and results Uses a significant number of tables, circuit and block diagrams, and waveform plots with well-designed, class-tested problems/solutions and projects designed for the best teaching-learning interaction Provides computer simulation programs as examples for ease of understanding and platforms for the projects Covering major power-conversion applications that help professionals from a variety of industries, Integration of Green and Renewable Energy in Electric Power Systems provides practical, application-oriented system analysis and synthesis that is instructional and inspiring for practicing electrical engineers and researchers as well as undergraduate and graduate students.

Download or read book Advanced Control Methods on Three phase Inverters in Distributed Energy Resources written by Sara Yazdani and published by . This book was released on 2020 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This research is an endeavor to apply new and well-established control methodologies to improve transient response, stability and reliability of three-phase inverters in grid-connected and isolated mode of operation. In the course of studying the effect of these methodologies, model-based control is introduced and is extensively applied which is relatively a new approach. In addition, the application of this concept has been studied on developing ''grid-forming'' controls to allow wind and solar inverters to support voltage and frequency levels like traditional generators. This research encloses the details of three major works of this research and their possible contributions on improving the performance of three-phase inverters in grid-connected and isolated mode of operation. The first one employs the concept of adaptive control using multiple models and a hierarchical control approach to smoothly switch between isolated and grid-connected modes of operation. In the second work, the features of the first research work have been applied and more nourished to control a ''grid-forming'' unit. The interactions of this grid-supporting converter with a ''grid- forming'' unit is the main subject of discussion in this work. The last work applies the concept of internal-model control to introduce a new control methodology in power-synchronization method. This approach has tackled the non-minimum phase issue attributed to power-synchronization methodology and offers a robust solution. Furthermore, in this research, detailed stability analysis of all the proposed control structures have been presented. Along with all simulation verification, FPGA-Based Hardware-in-the-Loop (HIL) has been utilized to verify the performance of the discrete control structure. The details of plant modeling, controller design, HIL and experimental results are presented for all of the proposed schemes in each section"--Abstract, page iv

Download or read book Design Control and Harmonic Compensation for Stand Alone and Grid Connected Voltage Source Converters Simulation and Experimental Validations written by Ahmed Ali Nazeri and published by BoD – Books on Demand. This book was released on 2024-01-01 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Voltage source converters (VSCs), among other power converters, play a crucial role in supplying power to both local loads and the grid at the PCC. During stand-alone operation, VSCs ensure stable power for loads by regulating the output voltage. In grid-connected mode, the regulation shifts to controlling output current, such as converter side current (CSC) or grid side current (GSC), to inject sinusoidal current into the electrical grid. The nonlinear characteristics of the loads connected to the power converters result in significantly distorted output voltages. This capability is crucial for applications such as uninterruptible power supply (UPS), emphasizing the importance of precise output voltage control. Similarly, in grid-connected mode, the CSC or the GSC is regulated to inject low THD current. The aim is to mitigate grid current harmonics arising from dead time and distorted grid voltages. Therefore, the harmonic mitigation of the grid current control is investigated in this work. This work presents the implementation of the proportional resonant plus multi-resonant (PR-MR) and practical proportional resonant plus multi-resonant (PMR-MR) harmonic controllers in the voltage and current control loops to mitigate the high-order harmonic currents.

Download or read book Grid Forming Power Inverters written by Nabil Mohammed and published by CRC Press. This book was released on 2023-02-28 with total page 307 pages. Available in PDF, EPUB and Kindle. Book excerpt: Grid-Forming Power Inverters: Control and Applications is the first book dedicated to addressing the operation principles, grid codes, modelling and control of grid-forming power inverters. The book initially discusses the need for this technology due to the substantial annual integration of inverter-based renewable energy resources. The key differences between the traditional grid-following and the emerging grid-forming inverters technologies are explained. Then, the book explores in detail various topics related to grid-forming power inverters, including requirements and grid standards, modelling, control, damping power system oscillations, dynamic stability under large fault events, virtual oscillator-controlled grid-forming inverters, grid-forming inverters interfacing battery energy storage, and islanded operation of grid-forming inverters. Features: Explains the key differences between grid-following and grid-forming inverters Explores the requirements and grid standards for grid-forming inverters Provides detailed modeming of virtual synchronous generators Explains various control strategies for grid-forming inverters Investigates damping of power system oscillations using grid-forming converters Elaborates on the dynamic stability of grid-forming inverters under large fault events Focuses on practical applications