A Novel Vertical-Axis Wind Turbine for Distributed & Utility Deployment

초록

KR Windpower, Inc. has developed a patented vertical-axis wind turbine line for both utility and distributed applications. Utility-scale turbines (1.5MW) are currently being installed in wind projects in Asia, while concomitant certification is ongoing. The KR wind technology has very high power-to-swept area efficiency and therefore works especially well around houses and buildings and in other applications where traditional three-blade horizontal axis turbines do not. Additionally, due to its low rotor speed (but with high torque, even at low wind speeds) and optimal rotor design, KR’s patented turbine is vitually noiseless, making it especially attractive for installation in residential and recreational areas. Field testing of 1, 3, and 5kW turbines has resulted in cut-in speed of 2.5m/s and rated speeds of 9~12 m/s. Thus, electricity is generated even at low wind speeds. This paper presents measured performances of a small-scale, vertical, wind turbine rated as 1 kW which has a tail consisted of a stabilizer and a rudder. Compared with the maximum power coefficient of 0.59 for a downsized model measured in a closed-type wind tunnel, the maximum turbine power coefficient averaged 0.5 at a tip-speed ratio of 0.5~0.6 in an open-type wind tunnel. The KR small-class turbines are based on IEC wind turbine classIII, which specifies that the highest 10 minute-mean wind speed is 37.5m/s or less for last 50 years. However, steady loadings by the extreme wind model of 52.5m/s were implemented, and the turbine was proven to be safe by its furling tail. A key element of KR Windpower’s strategy is to provide a turbine product, including a wind/solar hybrid concept, which addresses power and aesthetic needs of developers and communities.