Adaptive speed regulation of gearless wind energy transfer systems

The energy of wind can be transferred to the generator either by direct connection through a gearbox or by employing an intermediate medium such as hydraulic fluid. Gearless hydraulic wind power transfer systems are considered noble candidates to transfer wind energy to generators since they can collect the energy of multiple wind turbines in one generation unit. However, non-ideal dynamics of hydraulic systems imposed by pressure drops, leakage coefficient variations, and motor/generator damping coefficient, degrade the performance of power generation. This paper introduces a model reference adaptive controller (MRAC) to maintain and track a reference speed profile at the generator of a hydraulic wind power transfer. The mathematical modeling of a gearless hydraulic wind power transfer is presented and used to generate an accurate model of the plant. The control performance is verified with simulation results, which demonstrates a close tracking profile.