Sergio Daher was born in Fortaleza-Brazil on the 3rd of August 1971; son of Elias Daher and Josephina Sophia Lira Daher. Since young, he showed interest in sciences and latter he gave special attention to the electrical and electronic engineering areas, what remains until today. His main areas of interest are: Power Electronics, Renewable Energy Systems, Electronic Instrumentation and Control Systems.
He believes that is possible to make the world better: all together, starting now, within our life context, doing small daily contributions.
Technical in Electricity (15th January 1990)
Federal Technical School of Ceara – ETFCe – Fortaleza – Brazil
Graduation in Electrical/Electronic Engineer (28th January 1995) Universidade Federal da Paraiba – UFPb – Campina Grande – Brazil
Msc. in Electrical Engineer (12th September 1997)
Universidade Federal do Ceara – UFC – Fortaleza – Brazil
"A Small Wind Generator Based on a Three-phase Induction Machine for Isolated Operation"
Dr. – Ing. in Electrical Engineer (Defense day: 28th June 2006)
Universitat Kassel – Kassel – Germany
"Analysis, Design and Implementation of a High Efficiency Multilevel Converter for Renewable Energy Systems”
2000 – 2003 Assistant Lecturer – Department of Electrical Engineering – 20 hours
Universidade Federal do Ceara – UFC – Fortaleza – Brazil
Electrical Machines, Electrical Measurements, Micro controlled Systems.
2001 – 2004 Assistant Lecturer – Department of Electronic Engineering – 12 hours
Universidade de Fortaleza – UNIFOR – Fortaleza – Brazil
Analog Control Systems, Discrete Control Systems, Orientation of Works.
1996 – 1998 Founder/Director/Engineer
Elementar Engenharia Ltda – Fortaleza – CE – Brazil
Head of diverse projects: Electronic Traffic Controller, Monitored Security Access Control, Microcontroller Development Boards and others.
1999 – 2005 Founder/Director/Engineer
Dahaco Engenharia e Rep. Ltda – Fortaleza – CE – Brazil
Head of diverse projects: Industrial Controller for Wheat Mill Factory, Outdoor Electronic Panel, Dedicated Data-Acquisition System, Wireless Automation Syst. for Restaurants, Advanced Traffic Controller, and others.
Contact Information
E-mails: sdaher@secrel. com. br or serdaher@gmail. com
CV in Internet: http://lattes. cnpq. br/7235893980985596 or thought search within http://lattes. cnpq. br/
Kassel, 08thAugust 2006
[1] Are considered conventional sources: fossil-fuels, nuclear, geo-thermal and large hydro-power,
[2] Are considered renewable sources: solar, wind, marine and small hydro.
[3] For example, in a region where natural source of vegetable oil is available, it could be used as combustible to feed a motor-generator instead of conventional diesel. In turn, production of the oil can also generate sub-products that can improve the local economy.
[4] In this work, it is considered systems for general purpose applications, where the load nature can be diverse, subjected to changes or not precisely defined.
[5] Standard AC voltage used in utility distribution systems. Frequency and voltage can vary from country to country. Typical voltages are 110, 115, 120, 220, 230 and 240 VAC. Frequencies are worldwide fixed in 50 Hz or 60 Hz.
[6] Th e most commonly energy storage devices used in SARES are batteries and full-cells.
[7] In terms of reliability, efficiency, surge power and cost.
[8] High power: > 1 MW.
[9] Mini-grids are larger SARES that combines several generators (usually distributed) in order to form a small grid.
[10] Several RE sources are highly intermittent, such as solar and wind energy. Several others can be seasonal, including small hydropower, biomass and marine waves. Exceptions are geothermal and marine tide, which can present continuous or almost continuous capacity, respectively.
[11] Power can flow in both directions: from the DC side to the consumer side (inverter operation) and from de AC side to the battery (battery-charge-mode).
[12] There is lack of standards for RES inverters. Therefore, some specifications, such as maximum voltage THD of 5%, have been widely accepted and are copied from diverse other standards.
[13] Some are: reliability, efficiency, surge power capability and degree of protection: in order of importance.
[14] For example: communication features, operation modes and utility interaction capability.
[15] The Bathtub curve plots the failure rate over time and it is divided in three intervals that are modeled by three distinct Weibull distribution functions.
[16] In practice, it was observed that the transformer may present an asymmetric magnetizing current even if it is supplied with a zero dc level voltage. In other words, the balanced transformer operation can be only ensured by using closed loop control, such as the one described in this work.
[17] This is the origin of the term "floating".
