การพัฒนากังหันลมขนาดเล็กเพื่อผลิตพลังงานไฟฟ้าที่เหมาะกับความเร็วลมต่ำในประเทศไทย

Abstract

This research studies how to develop a small wind turbine suitable for low wind speed conditions in Thailand. By developed a number of elements such as wind turbine shapes and generators for that small wind turbines can actually generate electricity under low wind speeds. The types of wind turbines that were Vertical Axis Wind Turbine which are S Shape Wind Turbine and Leaf Shape were developed by using the propeller radial overlap ratio and Aspect Ratio and end plates area theory to improve the shape and increase the efficiency of the wind turbines and use the wind speed data from the meteorological station and the wind speed data from measurement in outside area to analyze and design the wind turbine. At the selected area in Chiang Mai found that the wind speed was the lowest in the winter and an average of 1.15 meters per second. The test was performed in the wind tunnel and connected with a Axial Flux Permanent Magnet Generator. In the test, the blade radius distortion theory and head and tail cover theory were used only for wind turbine design due to wind tunnel height restrictions measuring and recording the starting wind speed, wind turbine speed (RPM), and DC Voltage, the tested values were analyzed to improve efficiency and test the area. Outside area It was found that the S shape wind turbines start to spin at a wind speed of 0.63 meters per second turbine have speed was 48.31 rpm, Leaf shape wind turbine start to spin at 0.81 meters per second. The S shape wind maximum power was 0.479 watts and a maximum efficiency was 2.873 percent, which was 0.143 percent higher than the maximum efficiency of the leaf turbine at 0.143 watts and the highest efficiency of 1.443 percent. The theory that affects the efficiency of wind turbines in wind tunnel testing is area of end plates wind turbine which of the S-shaped windmills have more area than leaf-shaped windmills from wind tunnel testing, the S wind turbine was selected to improve efficiency by adjusting the size and design of the generator to suit the wind turbine and using the height-to-diameter ratio theory to improve the shape of the wind turbine by conducted tests in a closed room and compared the connected and disconnected generators. It was found that without connecting, the generator began to spin at 0.54 m / s. When connected, the generator began to spin at 0.61 m / s. It was found that there was a 1.29 per cent difference in speed at a wind speed of 6.65 m / s. Which close to the average wind speed in the summer in Chiang Mai province and at the same wind speed, the wind turbine can generate 32.28 watts of electrical power Coefficient or efficiency as high as 13.21 percent, and at wind speed 5.64 meters per minute produces a voltage of 14.64 volts, which is sufficient to charge a 12 volt rated battery. From outside testing of wind speed in winter, it was found that the average wind speed was only 2.12 m/s. Thus, the improved wind turbines produced only 1.326 watts of electricity, but compared to the design discrepancy, it was only 1.13 percent false, compared to the electrical energy produced with measured wind power. Based on the improvements of the wind turbines in this research, the methods that enable the wind turbines to start rotating at low wind speeds are: Increasing the area of the end plates (End Plates Area) and the way to increase efficiency is to adjust the aspect ratio of the height to diameter (Aspect Ratio), another factor affecting performance is To design a generator to suit the wind turbine by using the wind speed measurement. It can be concluded that three wind turbines from the improvement in this research can be started at low wind speeds in winter in Chiang Mai province and have the possibility of generating electricity at wind speed in summer. In the winter, the wind speed is not high enough and the design data is misleading, that is wind speed in winter which must be measured at least 1 year for more accuracy in designs to suit low wind speeds in winter.