Study of Pivot Panel Mechanism on the Self Start-Ability of a Darrieus Wind Turbine

Abstract

In South East Asia countries such Malaysia, wind turbine is generally not suitable to be used in large scale to generate electricity due to inconsistent wind speed and suitable land site availability. However, a small scale application is of preference as the wind speed in the region lies within the low speed range of approximately 2-5 ms-1 with intermittent highs up to 8 ms-1. The performance of Vertical Axis Wind Turbines (VAWTs) is known to be better compared to Horizontal Axis Wind Turbines (HAWTs) in urban conditions due to its omnidirectionality, which allows it to operate in fluctuating turbulent wind conditions. However, the major drawback of VAWTs is the inability to self-start under low wind speed conditions. Hence, the objective of this work is to investigate the Pivoting Panel Mechanism (PPM) which aims to assist VAWT models to self-start at low wind speed condition. Three sets of PPM width configurations (70mm, 80mm, 90mm) are used to study the effect of increasing the pivot panel surface area on the VAWT performance. Performance test showed that the PPM model improved the power coefficient values at the tip wind speed range of TSR<0.75 (PPM 70mm>80mm>90mm). Further investigation revealed that the larger PPM surface area (90mm) was able to assist the VAWT model to achieve a shorter RPM response time at wind speed of v = 2.5ms-1 and 2.9ms-1. These findings have considerable implications for future researches for the optimization of PPM design parameters and its adaptations in VAWT turbine design.