Abstract
Stand-alone small-scale wind turbine-generator systems have many problems on maintenance because they are operated in regions with less accessibility. In our target system, a straight-wing vertical axis wind turbine (with self-starting capability) is mainly operated at a constant tip speed ratio, which means a maximum power coefficient, by a rotational speed-squared load torque control. The previous studies clarified that this system possesses high power generation capability; however, it is significantly deteriorated due to performance deterioration of the wind turbine. This study develops an indicator for searching a rotational speed-squared load torque characteristic for a constant tip speed ratio operation adapted to performance deterioration of the wind turbine through a numerical simulation.
