Constrained Power Reference Control for Wind Turbines

TL;DR

This paper presents a control strategy for wind turbines that dynamically adjusts power output to optimize energy capture while maintaining load constraints, leading to increased efficiency and safety.

Contribution

The paper introduces a constrained power reference control method that adaptively manages turbine power output based on transient estimates, improving energy capture without exceeding load limits.

Findings

Generator speeds and blade loads stay within original limits.

Increases annual energy production by 5%.

Tower fore-aft damage loads increase by only 1%.

Abstract

The cost of wind energy can be reduced by controlling the power reference of a turbine to increase energy capture, while maintaining load and generator speed constraints. We apply standard torque and pitch controllers to the direct inputs of the turbine and use their set points to change the power output and reduce generator speed and blade load transients. A power reference controller increases the power output when conditions are safe and decreases it when problematic transient events are expected. Transient generator speeds and blade loads are estimated using a gust measure derived from a wind speed estimate. A hybrid controller decreases the power rating from a maximum allowable power. Compared to a baseline controller, with a constant power reference, the proposed controller results in generator speeds and blade loads that do not exceed the original limits, increases tower fore-aft damage equivalent loads by 1%, and increases the annual energy production by 5%.