Predictive Direct Power Control of Doubly Fed Induction Generators to Reduce the Power Ripple During the Grid Synchronization

Abstract

This paper presents a new method of predicting power based on predictive direct power control. This method reduces power ripple in a doubly fed induction generator, which makes it possible to have a smoother synchronization with the grid in low constant frequency switching. To achieve fast and smooth grid synchronization without any over current, the difference between the measure, frequency, and the phase of the stator voltage and the grid voltage should be minimized. This condition can be achieved by minimizing the error between active and reactive virtual power and their references. By predicting the virtual active and reactive power behavior and choosing different active voltage vectors and using each of them at different times among each period time, the best switching of the rotor side converter in doubly fed induction generator to have a smoother condition can be chosen. In this paper, a 15kw generator is simulated by the classic method which is direct power control, and this new method, predictive direct power control, and it will be shown how much the new method reduces the power ripple to have a smoother synchronization that doesn’t cause mechanical or electrical pressure for none of the grid and the doubly fed induction generator.