In this work we investigate some computational aspects of the eigenvalue calculation with edge elements; those include: the importance of the grid generator and nodeedge numbering. As the examples show, the sparse structure of the mass and stiffness matrices is highly influenced by the edge numbering. Tetrahedral grid generators are mainly designed for nodal based finite elements so an edge num...

This paper presents a coordinated control strategy for a hybrid wind farm with doubly-fed induction generator (DFIG)and direct-driven permanent-magnet synchronous generator (PMSG)-based wind turbines under symmetrical grid faults. The proposed low-voltage ride-through (LVRT) strategy is based on a novel current allocation principle and is implemented for individual DFIGor PMSG-based wind turbin...

The doubly-fed generators (DFIG) have clear superiority for the applications of large capacity and limited-range speed control case due to the partially rated inverter, lower cost and high reliability. These characteristics enable the doubly-fed wound rotor induction machine to have vast applications in wind-driven generation.In this paper Combined Vector and direct power control (CVDPC) strate...

The matrix converter has many advantages in wind power system applications. Matrix converter is compact and highly efficient because it directly converts generated power from AC generator to AC grid without intermediate DC bus while conventional back-to-back converter systems requires many electrolytic capacitors in DC link bus which are bulky and have short life-time. Matrix converter has both...

Renewable energy is derived from natural processes that are replenished constantly. Included in the definition is electricity and heat generated from solar, wind, ocean, hydropower, biomass, geothermal resources, and bio-fuels and hydrogen derived from renewable resources. Each of these sources has unique characteristics which influence how and where they are used. This paper presents the model...

: Induction generators are gaining the popularity due to its simplicity and no synchronization problem. However the major drawback of this machine is its additional reactive burden on the system, where it is connected. In this paper an attempt is made to explore the performance of a grid connected induction generator (GCIG) due to weak grid conditions i.e. voltage and frequency fluctuations. It...

The article discusses application of AC/DC/AC converter cooperating with an induction generator in small hydroelectric power plants. The induction generator works with power grid or a separated group of receivers, enabling to generate power even at low speeds of the turbine. The article provides also results of the investigation concerning the functioning of the generator coupled with AC/DC/AC ...

Solutions Efficient operation of the gas turbine imposes the demand for very high rotational speed of the generator 240,000 rpm. The permanent magnet machine has been chosen as the generator type since this technology is the most promising for high-speed machines: it offers high efficiency and very high power density at low volumes. A high-frequency power converter is required to enable bi-dire...

In order to meet increasing power demand, taking into account economical and environmental factors, wind energy conversion is gradually gaining interest as a suitable source of renewable energy. In this paper, The modeling of the Wind Energy Conversion System (WECS) with Matrix converter i s p r o p o s e d . The matrix converter, as a power electronic converter, is used to interface the induct...