Numerical solution of the stationary navier-stokes equations by means of a multiple grid method and newton iteration. Distributive iterationen f ur indeenite Systeme als Gll atter in Mehrgitter-verfahren am Beispiel der Stokes-und Navier-Stokes-Gleichungen mit Schwerpunkt auf unvollstt andingen Zerlegungen. PhD thesis, Christan-Albrechts Universitt at, Kiel, 1986. 145. G. Wittum. Linear iterati...

This paper presents a control strategy for a grid connected doubly fed induction generator (DFIG)-based wind energy conversion system (WECS).Control strategies for the grid side and rotor side placed in the rotor circuit of the Doubly Fed Induction Generator (DFIG) are presented along with the mathematical modeling of the Wind Energy Conversion System. In this control approach, wind generators ...

Wind energy is a leader area of application for variable-speed generators operating on the constant grid frequency. This paper depicts the power quality enhancement in wind power system using permanent magnet synchronous generator (PMSG) and Quasi Z-source Inverter. The PMSG is connected to the power network by means of a quasi z-source inverter (qZSI). The PMSG are used by these technologies d...

The paper proposes a back-to-back 2L-3L grid connection topology for a marine current energy converter. A prototype marine current energy converter has been deployed by a research group at Uppsala University. The concept behind the prototype revolves around a fixed pitch vertical axis turbine directly connected to a permanent magnet synchronous generator (PMSG). The proposed grid connection sys...

In this paper, based on the similarity, in structure and principle, between a grid-connected converter for a direct-driven permanent magnet synchronous generator (D-PMSG) and an active power filter (APF), a new D-PMSG-based wind turbine (WT) system configuration that includes not only an auxiliary converter in parallel with the grid-side converter, but also a coordinated control strategy, is pr...

This paper proposes a variable speed control scheme of grid-connected wind energy conversion system, WECS, using permanent magnet synchronous generator. The control algorithm tracking the maximum power for wind speeds below rated speed of wind turbines (WTs) and ensure the power will not exceed the rated power for wind speeds higher than the rated speed of wind turbine. The control algorithm em...

The formulation of a grid point shallow-water model proposed by C^ ot e and Stan-iforth is described. The model employs a hybrid nite-volume//nite-element spatial discretisation on a staggered Arakawa B type grid, where the geopoten-tial is computed at grid points and the wind u is found at grid cell centers. Time integration is based upon a two-time-level semi-implicit, semi-Lagrangian scheme....

In this thesis we study so-called two-grid hp-version discontinuous Galerkin finite element methods for the numerical solution of quasilinear partial differential equations. The two-grid method is constructed by first solving the nonlinear system of equations stemming from the discontinuous Galerkin finite element method on a coarse mesh partition; then, this coarse solution is used to linearis...