Yaw Control of Small Wind Turbines With a New Passive Tail Device: Part 1 — Steady-State Case

This paper describes the behavior of a new tail device to yaw smoothly small wind turbine rotors out of the wind during strong wind or gusts. The passive tail device consists of a rigid short tail, an aerodynamic rotating vane, a tail bumper, and a spring. This passive tail device reduces gyroscopic loads, is easy to adjust, can be manufactured in smaller sizes, and is much stronger than conventional vanes used in small wind machines. Besides, the energy collected with it is greater. Field test results indicate that its behavior agrees very well with simulations, and that the regulator can be advantageously utilized, as compared with conventional vanes and other mechanical or electromechanical means, in horizontal-axis wind turbines with diameters of 12 m or smaller. Here the steady-state case (quasi-steady wind velocity is assumed) is analyzed, showing the technical viability of the regulator proposed.Copyright © 2003 by ASME