Power performance enhancement of vortex-induced vibration wind turbines using a semi-active control approach

ABSTRACT

Bladeless wind turbines based on vortex-induced vibration usually consist of a cylindrical body mounted on a flexible support. An inherent feature of this kind of turbines is that the power generation is considerable only in a narrow wind speed band, when the frequency of shedding vortices is close to the structural natural frequency. The present study proposes a novel semi-active approach for tuning the turbine response to widen the effective power generation region. Based on numerical modeling of aeroelasticity interaction phenomenon, a parametric analysis is done and the effective parameters on the turbine performance are highlighted. The proposed tuning technique then works to maintain the effective parameters at the optimum value from the power generation point of view. To realize this, a supporting mechanism is suggested that can change the elastic member length and consequently structural natural frequency. However, to avoid phenomenon attenuation due to power extraction process, a second level of tuning the structure damping ratio is added. Results of numeric simulations showed that, compared to previous work, the proposed approach has considerably broadened the effective wind speed range. The conversion efficiency is greater than or equal 15% over a wind speed range of 3.3–6 m/s.

KEYWORDS:

• Vortex-induced vibration
• bladeless wind turbine
• lock-in phenomenon
• wind energy harvesting
• semi-active control

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Notes on contributors

Magdy Roman

Magdy Roman, an assistant professor dynamic systems modeling and control at Mechanical Power Engineering department, Helwan Uni, Egypt.

Rowida Sobh

Rowida Sobh, is a teaching assistant at the mechatronics and robotics department, Egyptian Russian Uni, Egypt.

Momtaz Sedrak

Momtaz Sedrak, professor of fluid mechanics at Mechanical Power Engineering department, Helwan Uni, Egypt.

Mohamed Ali

Mohamed Ali, an assistant professor of automatic control systems at Mechanical Power Engineering department, Helwan Uni, Egypt.