PSI - Issue 27

Dandun Mahesa Prabowoputra et al. / Procedia Structural Integrity 27 (2020) 155–162 Prabowoputra et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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Wind turbines generally consist of two types, namely Horizontal Axis and Vertical Axis. Fig. 2 shows the distribution of types of wind turbines and Fig. 3 shows the Performances of the main conventional wind machines. Horizontal axis wind turbine (HAWT) is a turbine that rotates on the horizontal axis and parallels the direction of airflow. The Vertical Axis Wind Turbine (VAWT) is a turbine that rotates in a vertical direction and is perpendicular to the direction of the airflow (Zhao et al., 2019). HAWT has a higher efficiency than VAWT (Cengel and Cimbala, 2017). HAWT has several advantages over VAWT is (Zhao et al., 2019):  HAWT is the most stable wind turbine design to be applied  HAWT can operate at relatively lower cut-in wind velocity and result in higher energy conversion efficiency.  HAWT has excellent performance at fluctuating wind velocity, due to better attack angle control. HAWT has disadvantages, among others (Zhao et al., 2019):  HAWTs require yaw drives to turn the turbine toward the oncoming wind.  More substantial structural support is needed for massive generators and gearboxes.  Installation and maintenance costs are higher because of the taller tower height.

Horizontal Axis

Three-blades

Wind Turbine

Savonius

Vertical Axis

Darrieus

Giromill

Fig. 2. Classification of Wind Turbine (Zhao et al., 2019).

Fig. 3. Performances of primary conventional wind machines (Menet, 2004).