CONTROL METHOD AND APPARATUS OF WIND MACHINE FOR PLANT FROST PROTECTION

• US 20110247263A1
• Filed: 09/05/2008
• Published: 10/13/2011
• Est. Priority Date: 07/16/2008
• Status: Active Grant

• Current Assignee: Jiangsu University (Jiangsu Education Department), Jiangsu Yinchunbiya Tea Research Institute Co., Ltd.
• Original Assignee: Jiangsu University (Jiangsu Education Department)
• Inventors: Zhang, Xiliang, Wang, Xiuhong, Li, Pingping, Hu, Yong-guang
• Granted Patent: US 8,701,341 B2
• Time in Patent Office: Days
• US Class Current: 47/2
• CPC Class Codes: A01G 13/08 Mechanical apparatus for circulating the air

Abstract

This invention relates to control method and apparatus of wind machine for plant frost protection, and belongs to the domain of agro-meteorological disaster monitoring and control. Existing wind machines for plant frost protection only rely on critical damage temperature or wind speed as a condition to start. If there is no thermal inversion, operation of the wind machine will aggravate freezing injury to plants. If the strength of thermal inversion is weak, the effect will be minimal The feature of this invention is that when temperature at the plant canopy is lower than the critical damage temperature of a certain plant and temperature difference between the top and bottom of the thermal inversion layers exceeds set threshold, wind machine will start automatically. Otherwise it will remain off. The control apparatus mainly consists of sensor 5 at the top of thermal inversion layer, sensor 7 at bottom of thermal inversion layer, and controller 4. This invention of the control of frost protection wind machine ensures rational and effective operation and avoids aggravated freezing risk due to misuse of energy and incorrect operation.

Claims

1. A control method for wind machines used to mitigate and potentially prevent frost and freeze damage to plants, wherein wind machines will automatically start when the temperature at plant canopy is lower than the critical damage temperature and temperature difference through thermal inversion layer exceeds a certain threshold, and will automatically stop otherwise.

2. The control method for wind machines used to mitigate and potentially prevent frost and freeze damage to plants of claim 1, wherein said thermal inversion temperature different threshold is set to 1.5˜

6.0°

C.

3. The control method for wind machines used to mitigate and potentially prevent frost and freeze damage to plants of claim 1, wherein the control device mainly comprises of temperature sensor (5) at the top of near-ground atmospheric thermal inversion layer (8), temperature sensor (7) at the bottom of thermal inversion layer (8), and controller (4). Said temperature sensors (5) and (7) are used to detect temperature in real time and transmit temperature information to controller (4). Said controller (4) is used for sensing temperature, data analysis and automatic control of the start or stop of wind machines according to current conditions.

4. The control device for wind machines used to prevent and mitigate frost and freeze damage to plants of claim 3 wherein temperature sensor at the top of thermal inversion layer is installed within the range of 4˜

10 m above ground.

5. The control device for wind machines used to prevent and mitigate frost and freeze damage to plants of claim 4, wherein temperature sensor at the bottom of thermal inversion layer is installed at plant canopy.

6. The control device for wind machines used to prevent and mitigate frost and freeze damage to plants of claim 3, wherein said present conditions are:

If canopy temperature is lower than critical damage temperature and temperature difference through the thermal inversion layer exceeds the threshold, wind machines will start. Otherwise they remain turned off.