ABSTRACT
This chapter discusses the general design approach of horizontal axis wind turbine rotors, regardless of the same being slow or fast. The input data to design a wind turbine rotor are: the desired kind of turbine (slow for water pumping, fast for electrical generation), the required nominal power, and the nominal wind speed, which is a characteristic of the site. The chapter explains step by step the calculation sequence. A common design criterion consists in limiting the blade tip's speed to 80 m/s, not only for structural but also for acoustical reasons. The chapter presents the strategies of speed control for fixed pitch turbines. It explains three methods to control the pitch of the blades. They are: variation of the pitch by means of servomechanisms; variation of the pitch by means of centrifugal force; and sketch of pitch control by independent centrifugal masses attached to each blade.
