There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

http://ieeexplore.ieee.org/iel5/5610941/5624686/05624745.pdf

Power electronics

The fifth edition of "Numerical Methods for Engineers" continues its tradition of excellence. Instructors love this text because it is a comprehensive text that is easy to teach from. Students love it because it is written for them--with great pedagogy and clear explanations and examples throughout. The text features a broad array of applications, including all engineering disciplines. The revision retains the successful pedagogy of the prior editions. Chapra and Canale's unique approach opens each part of the text with sections called Motivation, Mathematical Background, and Orientation, preparing the student for what is to come in a motivating and engaging manner. Each part closes with an Epilogue containing sections called Trade-Offs, Important Relationships and Formulas, and Advanced Methods and Additional References. Much more than a summary, the Epilogue deepens understanding of what has been learned and provides a peek into more advanced methods. Approximately 80% of the end-of-chapter problems are revised or new to this edition. The expanded breadth of engineering disciplines covered is especially evident in the problems, which now cover such areas as biotechnology and biomedical engineering. Users will find use of software packages, specifically MATLAB and Excel with VBA. This includes material on developing MATLAB m-files and VBA macros.

Numerical methods for engineers

Control in Power Electronics : selected problems

The increased penetration of Distributed Energy Resources (DER) is challenging the entire architecture of conventional electrical power system. Microgrid paradigm, featuring higher flexibility and reliability, becomes an attractive candidate for the future power grid. In this paper, an overview of microgrid configurations is given. Then, possible structure options and control methods of DER units are presented, which is followed by the descriptions of system controls and power management strategies for AC microgrids. Finally, future trends of microgrids are discussed pointing out how this concept can be a key to achieve a more intelligent and flexible power system.

A Review of Power Electronics Based Microgrids

This paper illustrates the importance of control on energy saving opportunity in electrical drives systems. The paper's objective is to develop an optimal control law for an electrical position drive systems with induction machine (IM) using a voltage source inverter. The optimal control provides dynamic regimes with minimum input energy and performs the minimization of the copper losses from IM. The solution of the problem uses optimal control theory and the numerical integration of the matrix Riccati differential equation (RMDE). The synthesis of the optimal energetic control law is accomplished by comparing, via simulation, the two control methods: conventional and optimal.

The optimal control for position drive system with induction machine

In this paper the topology of the grid-connected fuel cell power system and the performances of the front-end three-phase power inverter are presented The proposed topology has been designed and benefits of the small plastic film dc link capacitor thanks to the power balance control of the entire power conditioning system, and thus replacing the bulk dc link electrolytic capacitor By using the load feedforward control the input reference of the current is changed with load and thus a better transient response is obtained The increase in the power response of the dc-ac inverter makes it possible to reduce the size of the DC link capacitor by maintaining the systems' stability The final power conditioning system has the following advantages: independent control of the active and reactive powers, minimize harmonic current distortion offering a nearly unity power factor operation, operation capability, dc link voltage regulation, fast disturbance compensation capability, high reliability, and low cost The proposed control was successfully implemented by the author on quasi direct ac-ac converter and based on the Matlab/Simulink software the simulation test has been performed for the modified topology The performances of the grid power inverter are shown The comparative results between the proposed topology and the ac-ac converter are reported

Inverter Control for Three-Phase Grid Connected Fuel Cell Power System

The paper presents the motion control of a single-beam gantry crane trolley. Nonlinear mathematical model deduction of the gantry-crane, followed by linearization of the gantry-crane trolley mathematical model in order to integrate a linear state-feedback controller by using Ackermann formula have been shown. In order to obtain a zero-steady state error an adequate pre-filter has been designed. The simulation results demonstrates that the system can successfully be handled by using state-feedback controller type, combined with the designed reference filter in order to obtain a zero steady state error.

Motion control of a single-beam gantry crane trolley

Active Power Compensator of Current Harmonics Based on the Instantaneous Power Theory

The main objective of the chapter is the development of technological knowledge, based on Matlab/Simulink programming language, related to grid connected power systems for energy production by using Renewable Energy Sources (RES), as clean and efficient sources for meeting both the environment requirements and the technical necessities of the grid connected power inverters. Another objective is to promote the knowledge regarding RES; consequently, it is necessary to bring contribution to the development of some technologies that allow the integration of RES in a power inverter with high energy quality and security. By using these energetic systems, the user is not only a consumer, but also a producer of energy. This fact will have a direct impact from technical, economic and social point of view, and it will contribute to the increasing of life quality.

/pdf/matlab-simulink-based-grid-power-inverter-for-renewable-2ovm4a7nes.pdf

Marian Gaiceanu

Papers

The optimal control for position drive system with induction machine

Inverter Control for Three-Phase Grid Connected Fuel Cell Power System

Motion control of a single-beam gantry crane trolley

Active Power Compensator of Current Harmonics Based on the Instantaneous Power Theory

MATLAB/Simulink-Based Grid Power Inverter for Renewable Energy Sources Integration