Power Kites for Wind Energy Generation [Applications of Control]

To overcome the limitations of current wind power technology, the KiteGen project was initiated at Politecnico di Torino, Italy, to design and build a new class of wind energy generators in collaboration with Sequoia Automation, Modelway, and Centro Studi Industriali. The project focus is to capture wind energy by means of controlled tethered airfoils, that is, kites. The KiteGen project has designed and simulated a small-scale prototype. The two kite lines are rolled around two drums and linked to two electric drives, which are fixed to the ground. The flight of the kite is controlled by regulating the pulling force on each line. Energy is collected when the wind force on the kite unrolls the lines, and the electric drives act as generators due to the rotation of the drums. When the maximal line length of about 300 m is reached, the drives act as motors to recover the kite, spending a small percentage (about 12%, see the "Simulation Results" section for details) of the previously generated energy. This yo-yo configuration is under the control of the kite steering unit (KSU), which includes the electric drives (for a total power of 40 kW), the drums, and all of the hardware needed to control a single kite. The aims of the prototype are to demonstrate the ability to control the flight of a single kite, to produce a significant amount of energy, and to verify the energy production levels predicted in simulation studies.