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Under the condition of late spring cold in early spring, tea plant suffers much damaged by frost, which causes low production and quality. On this occasion, temperature inversion occurs, which can be utilized to push upper warmer air downward to the cold tea plants so as to increase the temperature of tea canopy and prevent frost damage. Based on the principle, elevated wind machine system for frost protection was designed, of which axial-flow fan was a key component. The control sub-system was developed to make the whole system automatic start or stop based on the difference between the upper and lower temperature. Experiments were conducted to test effective range and frost protection effects. The results showed that one system of 3 kW power could cover effective range of 1 000 m2 and increased temperature by 4℃ around tea canopy when ambient temperature was about -4℃. Therefore, the developed elevated wind machine system can effectively prevent frost damage. 