Today through Wind Volt-Amp-Reactive (“WindVAR”) electronics, voltage is controlled and regulated in real-time. Similar to conventional utility generator, WindVAR supplies reactive power to the grid at the time its needed. in a fraction of a second , regulating system voltage and stabilizing weak grids. With the ability to supply reactive power to the grid Wind VAR opens the door to new opportunities in areas where weak rural distribution systems had discouraged new wind power applications. The addition of a wind project equipped with WindVAR electronics can actually strengthen a weak grid. This system also has the potential to provide emergency back-up support and support to weak grids in need of transmission and distribution capital improvements. The turbine’s power electronics also reduces the in rush current to about 75% of full load current during the wind turbine’s start-up, and provides ride-through capability.
How It Works
WindVAR system is provided through the same power electronics employed in achieving variable speed operation. The variable speed technology which reduces torque transients and increase the blades ability to capture more of the kinetic energy available in the wind.
A voltage controller placed at the Point of Interconnect measures utility line voltage, compares it to the desired level, and computes the amount of reactive power needed to bring the line voltage back to the specified range. To reach the desired voltage level at the substation, the VAR Controller communicates the reactive power requirement to each of the projects wind turbines via a distributed control network. Individually each wind turbines power processor excites the generator to produce the commanded power factor. As the power factor changes, the measured line voltage moves toward the desired voltage level, forming a closed loop voltage control system.