Performance of Doubly Fed Induction Generator Driven by Wind Energy at Constant Stator Power and Current

Abstract

This paper discusses the performance of a wind-driven doubly-fed induction generator when connected to the grid. The stator is directly connected to the grid, while the rotor side connection happens via a back-to-back converter. The performance and the steady-state analysis of the Doubly Fed Induction Generator (DFIG) when running at constant stator power and when running at constant stator current will be discussed. Laboratory experiments are performed using a testing bench for the Lucas-Nülle wind power system and the results are analyzed using Lucas-Nülle WindSim software. DFIG analysis and laboratory experiment performance were performed for two different cases; the first case is when DFIG is running at a speed lower than the synchronous speed and the second case is when DFIG is running at a speed above the synchronous speed. In both cases, the values of rotor voltage, stator current, rotor current, and the total generated power from the stator and rotor for DFIG are calculated from the analysis using MATLAB file (mfile) and compared with the practical results.