Development of a grid-connected wind generation system utilizing high frequency-based three-phase semicontrolled rectifier-current source inverter

In this paper, a high frequency (HF)-based three-phase Semicontrolled rectifier-current source inverter system is proposed for grid-connected permanent magnet wind generators. The main advantages of the topology are: high efficiency due to less power losses and reduced number of switching elements, high output power density realization, reduced passive component ratings proportionally to the frequency, robustness, as short-circuit through a leg is not possible, and harmonics are of higher orders and are easily filtered out. As a disadvantage, higher but acceptable total harmonic distortion of the generator currents is introduced. A maximum power point tracking (MPPT) algorithm is achieved through a hysteresis control for the rectifier operation. Additionally, a sinusoidal pulse width modulation (SPWM) three phase current source inverter (CSI) is also employed in the grid connection. The complete operation of the rectifier-inverter and theoretical analysis are presented. Test results on 5-kW wind generation system are presented and discussed to confirm the effectiveness of the proposed topology for grid connected systems.