An Estimation Technique of Windmill Torque Loss Coefficients (Torque Coefficient) for Propeller Type Windmill

Abstract

There are a number of possible applications of the technique whenever a computer or microprocessor is available for control of a windmill or a sub-system of it, and also for control of more complex wind turbine systems. To simulate or/and control windmill power system by control sequence, we need to obtain the accurate values of the system parameters previously.
This paper describes a new method estimating windmill torque loss coefficients or torque coefficient of a propeller type windmill. In the method, time series data representing wind and windmill speed of a windmill power system are used for estimation. This paper is organized as follows; Paying attention to the energy flow of the propeller type windmill, we firstly discuss the mathematical windmill model and define the windmill torque loss coefficients, which are treated as a function of wind and windmill speed. Next, an estimation technique based on recursive estimation technique has been developed for determination of the values of these coefficients.
We manifested the validity of the proposed method by estimated results used from both the simulated results and the experimental data for step or natural changes in wind speed.