In today’s environment, the shortage of resources, environmental degradation has become a very prominent problem all over the country, how to reasonably develop and use renewable energy has become a hot topic. Wind energy as a non polluting renewable energy has great development potential. Wind industry has become a mature and promising industry in the field of new energy. At the same time, wind speed and direction sensor and ultrasonic wind speed and direction sensor have also been widely used.
1、 Application of wind speed and direction sensor
Wind speed and direction sensor is widely used in wind power generation; wind kinetic energy is converted into mechanical kinetic energy, and then mechanical energy is converted into electrical kinetic energy, which is wind power generation. The principle of wind power generation is to use the wind to drive the blades of the windmill to rotate, and then increase the rotating speed through the speed increasing engine to promote the generator to generate electricity.
Although the process of wind power generation is extremely environmentally friendly, the lack of stability of wind power generation makes the cost of wind power generation higher than other energy sources. Therefore, in order to control the wind turbine power generation well and make it obtain the limit power generation with the change of wind, so as to reduce the cost, it is necessary to accurately and timely measure the wind direction and wind speed, so as to control the wind turbine accordingly; in addition, the control of wind farm In order to provide a reasonable basis for analysis, it is also necessary to predict the wind speed and direction in advance. Therefore, using wind speed and direction sensor to accurately measure wind parameters is very important in wind power generation.
2、 Principle of wind speed and direction sensor
1. Mechanical wind speed and direction sensor
The mechanical wind speed and direction sensor can be divided into two types: wind speed sensor and wind direction sensor
Wind speed sensor
The mechanical structure wind speed sensor is a kind of sensor which can continuously measure wind speed and air volume (air volume = wind speed × cross-sectional area). The more common wind speed sensor is the wind cup type wind speed sensor, which is said to be invented by Robinson in the UK. The measuring part is composed of three or four hemispherical air cups, which are installed on the rotating support perpendicular to the ground at an equal angle in one direction.
Wind direction sensor
The wind direction sensor is a kind of physical device which detects and senses the external wind direction information by the rotation of the wind direction arrow, transmits it to the coaxial code disk, and outputs the corresponding wind direction related values at the same time; its main body adopts the mechanical structure of the wind vane, when the wind blows to the tail of the wind vane, the arrow of the wind vane will point to the direction of the wind. In order to maintain the sensitivity to the direction, different internal mechanisms are used to identify the direction of the wind speed sensor.
2. Ultrasonic wind speed and direction sensor
The working principle of ultrasonic is to use ultrasonic time difference method to measure wind speed and direction. Because of the speed of sound in the air, it will be superimposed with the wind speed. If the propagation direction of the ultrasonic wave is the same as the wind direction, its speed will increase; on the contrary, if the propagation direction of the ultrasonic wave is opposite to the wind direction, its speed will slow down. Therefore, under the fixed detection conditions, the speed of ultrasonic propagation in the air can correspond to the wind speed function. Accurate wind speed and direction can be obtained by calculation. When the sound wave propagates in the air, its speed is greatly affected by the temperature; the wind speed sensor detects two opposite directions on the two channels, so the influence of temperature on the sound wave speed can be ignored.
As an indispensable part of wind power development, wind speed and direction sensor has a direct impact on the reliability and power generation efficiency of wind turbine, and also directly related to the profit, profitability and satisfaction of wind power industry. At present, most wind power plants are located in the harsh natural environment, low temperature, dust environment, the working temperature and bending resistance of the system are very strict. The existing mechanical products are slightly deficient in this aspect. Therefore, the ultrasonic wind speed and direction sensor may have broad application prospects in the wind power industry.
Editor in charge: CC