Fuzzy Logic PI controller based Direct Torque control of a Self-Excited Induction Generator through a three-level Rectifier

The main goal of this work is to control the terminal voltage of a Self-excitation induction generator (SEIG) that supplies autonomous load and is driven by a variable speed wind turbine. More advanced strategies of control have been suggested and applied these through a two-level converter. However, in this paper, we propose to study a modified DTC approach which based on the use of three-level converter (NPC structure) and instead of the traditional PI controller, we use a PI fuzzy controller to reduce torque and flux ripples, the induction generator's stator flux and electromagnetic torque are controlled using voltage space vector selection. The proposed control strategy has to maintain constant DC bus voltage regardless of load or wind speed variations. Finally, it should be noted that this control accounts for the induction generator's magnetic saturation phenomenon

Energy Management of a Photovoltaic System with Hybrid Energy Storage Battery-Super capacitor

This paper describes a method for regulating the voltage of a DC bus of the hybrid power system pv/wind associated with storage devices. A hybrid energy storage system (HESS) that combines batteries and super capacitors (SCs) is an interesting solution. The batteries are employed to meet long-term energy requirements, while the using of SCs, to meet immediately the demand for instantaneous power. In this paper, we propose a new management strategy that manages energy flows between storage devices, by maintaining the SOC of super capacitor and the SOC of the batteries at acceptable levels and to reduce stress on batteries and improve their life cycle. the simulation results demonstrate the efficiency of the proposed energy management strategy for the sudden change in power generation and load demand