Hydraulic Wind Power Plants: A Nonlinear Model of Low Wind Speed Operation.

The structure of hydraulic wind power plants involves one or several high-pressure hydraulic pumps and a central power generation unit to combine the energy from wind turbines. As the wind speed drops, the energy generation may not be significant enough to run the main generator. Therefore, an auxiliary generator generates power for the storage devices. The system operation at low wind speed is highly nonlinear, as the power generation is not significant. This paper introduces a nonlinear model of hydraulic elements and offers the nonlinear dynamics of system operation at low speed. Nonlinear state-space representation of the hydraulic wind energy transfer is presented and validated by experimental implementations.