Review of mathematical models of both the power coefficient and the torque coefficient in wind turbines

This paper presents a review of different mathematical models of both the power coefficient and torque coefficient in wind turbines. These coefficients are used to realize the analysis of a wind turbine, depending on the type of turbine, which is used. The coefficients of power and torque establish the relationship between wind power and power obtained in the turbine. In the review were found various models, the goal of this paper is to classify to find a general model, however, due to the characteristics of the models found, the models were classified into three general groups. Each group was classified according to their mathematical expression, which was exponential, sinusoidal and polynomial. The exponential and sinusoidal models include variations in relation to the specific speed and the pitch angle; and the polynomial models only depend on the specific speed. The models consider the real characteristics of wind turbines. The purpose of this review is to establish mathematical models of power coefficient and torque coefficient, in order to evaluate different models of wind turbines on the emulator.