A critical review of voltage and reactive power management of wind farms

Wind generation is currently the major form of new renewable, generation in the world. The wind power is totally dependent on wind flow, due to randomness and uncertainty of wind flow, the wind power generation is quite fluctuating in nature and large scale wind farms may cause significant impact to the power system safety, quality and stability. The active power mainly depends upon the potential of the wind power produced and wind turbine generator design. The reactive power demand on the other hand depends upon conversion devices and recovered power quality fed to the grid. The wind farms which accesses to power grid cause fluctuations and reactive power redistribution and sometimes lead to voltage collapse. Similarly, the dynamic voltage stability is a major challenge faced by distribution network operators. The easy solution comes into picture is to install reactive power source devices with optimization of the existing assets to deliver enhanced reactive power to the grid. With solution to reliability, voltage regulation, reactive power requirements, grid integration problems, weak grid interconnection, off grid wind power generation and its integration to power grid, wind power penetration in distribution grid, wind power uncertainty, flicker and harmonics etc. The categorization of issue considered the goal of our work is the reactive power management of wind farm in most technical and economical way without compromising quality power system voltage, and considering the wind turbine technology for already commissioned wind farm, and change in WT technology in present scenario. More than 100 research publications on voltage and reactive power control of wind farms, extending from year 2003 to 2013 have been critically examined, classified and listed for quick reference.