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Wind turbine output power can be maximized using maximum power point tracking (MPPT). By estimating wind speed, the MPPT can be achieved easily by adjusting the speed of DFIG based wind turbine through back-to-back converter. The grid side unity power factor can be simply achieved using PI controller on hybrid inverter. The aerodynamic power captured by wind turbine is the cosine function of pitch angle. In this paper, the pitch angle is kept zero, which is a valid assumption for lower to medium wind velocities .The machine side converter (MSC) is used to track the maximum power point for different wind speed. The grid side converter (GSC) uses a vector current controller to supply power at unity power factor to the grid. The simulations have been performed using MATALB/SIMULINK. The effectiveness of proposed control methods validated.

Microgrids are becoming more popular and irresistible options for increasing system reliability and operation. One of the most important challenges in microgrid operation is the unintentional islanding occurrence. Unintentional islanding can cause serious safety hazards and technical issues. Islanding detection methods can be classified into active and passive methods. The proposed passive approach is based on Discrete Fourier Transform and decision-tree for detecting the intentional and nonintentional microgrid islanding. The proposed microgrid islanding detection approach is tested on a microgrid equipped with synchronous generator-based DGs. The proposed method is capable of detecting islanding with a speed accuracy less than three cycles from the islanding inception. The results of proposed method are compared with other existing techniques in terms of fast islanding detection, dependability, security and accuracy. The simulation results show that the proposed approach is effective in detecting islanding phenomenon possesses compared to existing islanding detection techniques.

Energy saving is considered one of the important factors for industrial and commercial applications. Induction motors are the mostly preferred motor in the industry due to their reliability, robustness, price and rugged construction. The largest percentage of consumed energy in the industrial section is consumed by induction motors. So, Energy conservation in induction motor drive leads to reduction in power consumption and electricity cost. This paper studies an energy saving technique for squirrel cage induction motor. The energy saving is achieved by controlling the voltage applied to the stator winding using the three phase AC voltage controller. The simulation verifications were performed using MATLAB/Simulink. The results show that the proposed scheme gives rise to considerable energy savings.