Extremum‐seeking control for energy‐harvesting enhancement of wind turbines with hydromechanical drivetrains

Abstract

AbstractEfficiency and reliability enhancement of distributed wind energy systems have been the subject of extensive research effort for the purpose of energy cost reduction and power availability. This work investigates the integration of a hydromechanical power split transmission into the drivetrain of a stall‐regulated wind turbine with a fixed‐speed generator to enhance the overall system efficiency without compromising its reliability. The proposed drivetrain configuration introduces a variable transmission ratio capability, thus enabling the turbine rotor to cope with varying wind speeds independent of the fixed generator speed. An extremum‐seeking control approach is adopted to maximize energy harvesting by controlling a variable geometric volume hydraulic pump without the need for wind speed measurement. Compared with a stall‐regulated fixed‐speed wind turbine, the performance of the proposed wind turbine configuration is evaluated in simulation environment under different wind speed conditions. The results demonstrate the ability of the proposed wind turbine configuration to significantly improve the system overall efficiency in partial and full‐load regions of operation. Consequently, the proposed wind turbine configuration with extremum‐seeking control can be considered as an efficient and reliable possible alternative for future distributed and isolated wind energy systems.