Horizontal axis wind turbine and method for measuring upflow angle

摘要

A horizontal axis wind turbine (1) comprises the following components: a horizontal plate (7) disposed on the upwind side of a rotational central portion of a rotor (4); a first anemometer (6) disposed at an upper position of the upwind side of the horizontal plate (7); a second anemometer (8) disposed at a lower position of the horizontal plate (7); and an upflow angle measuring section (100) for measuring an upflow angle based on a wind speed difference or a wind speed ratio obtained from wind speeds measured by the first anemometer (6) and the second anemometer (8).