Rotor Inertia, Ultracapacitors and Batteries for Wind Power Smoothing
The US wind power industry experienced growth of 45% in 2007, with over 5,200MW installed. According to a new technical report published by the US Department of Energy, the installed wind energy capacity could reach 300GW to meet 20% of the US electricity demand by the year 2030. However, the availability of wind energy is estimated at around 15 to 30%. To avoid frequency and voltage drifts due to short-term wind variations, and to lower the need for spinning reserves due to the intermittent nature of the wind in a system with higher wind energy penetration, different techniques may be utilised. Some tools that can be employed are rotor inertia, in variable speed wind turbines, and ultracapacitors for short-term and battery energy storage for long-term, power levelling.By Adel Nasiri, Assistant Professor, Power Electronics and Electric Motor Drives Laboratory, University of Wisconsin-Milwaukee, USA .
