Associated Press: China’s Goldwind Science & Technology Ltd. is one of the world’s biggest makers of wind turbines — a cornerstone of the booming clean power business — but is unknown outside its home country. Goldwind aims to change that. In a Minnesota farmer’s cornfield, the company is erecting three 20-story-tall windmills in its first American project and hopes it will help to woo other buyers. “There are a lot of leads and we are following them up,” said Kerry Zhou, Goldwind’s …