• Pravin Bhagwanrao Bhad
• Prof. Chandra O. Reddy
• Prof. Pankaj Bhakre

Power quality can be affected both due to utility side as well as the customer side abnormalities. The increasing gap of generation and demand has raised many options for the power generation. The use of renewable energy sources is increasing. One of the major researches in the area of wind turbine generator is Doubly Fed Induction Generator (DFIG). The DFIG is variable speed wind turbine facilitating the constant generation throughout the changing wind velocities. When these types of wind farms are connected to the microgrid, then it is difficult to predict their time of uninterrupted operation. Because, when wind farms are connected to grid, the grid codes are to be satisfied. One of the important requirements is the fault ride through ability of the wind farm. Faults in the power system affect the magnitude of current and voltage of the system. These fluctuations in the parameters create disturbance in the operation of the generators. The fluctuations bring generators into instability which may in turn result into loss of synchronism. The problems related to the voltage stability may be cleared by the use of custom power devices having ability to control the power in the circuits. One such reliable customer power device used to recover the problems related to the voltage is the Dynamic Voltage Restorer (DVR). It is a series connected custom power device, which is considered to be a reliable alternative when compared with other commercially available voltage sag/swell compensation devices. The main function of the DVR is to monitor the load voltage waveform constantly and if any sag or swell occurs, the balance voltage is injected to the load voltage. To achieve the above function a reference waveform of voltage has to be generated which is similar in magnitude as well as phase angle to that of the supply voltage. Thereby during any abnormality of the voltage waveform it can be detected by comparing the reference and the actual voltage waveforms. The DVR is applied to DFIG for maintaining the voltage output constant. The DVR compensates the faulty line voltage, during that the DFIG wind turbine continues its nominal operation as demanded in actual grid codes. So the reliability is improved with the use of DVR, and the DFIG is available for the production of electricity continuously. Simulation results for a 2 MW wind turbine are presented, for symmetrical and unsymmetrical grid faults.

Doubly Fed Induction Generator (DFIG), Dynamic Voltage Restorer (DVR), Low Voltage Ride Through (LVRT), MATLAB/Simulink.

"Fault Ride Through Technique of DFIG Under Faults by Using DVR", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 6, page no.339-344, June 2019, Available :http://www.jetir.org/papers/JETIR1906W43.pdf

"Fault Ride Through Technique of DFIG Under Faults by Using DVR", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 6, page no. pp339-344, June 2019, Available at : http://www.jetir.org/papers/JETIR1906W43.pdf