In today's environment, resource shortages, environmental degradation has become a very prominent problem throughout the country, how to rationally develop and utilize renewable energy has become a hot spot of widespread concern. Wind energy as a non-polluting renewable energy has great potential for development, the wind industry has become a new energy field, very mature and promising industries, while wind speed and wind direction sensors and ultrasonic wind speed and wind direction sensors have also been widely used.
First, the application of wind speed and wind direction sensor
Wind speed and wind direction sensors are widely used in wind power generation; the wind's kinetic energy into mechanical kinetic energy, and then the mechanical energy into electrical kinetic energy, which is wind power generation. The principle of wind power generation is to use the wind to drive the windmill blade rotation, and then through the speed booster will rotate the speed to promote generator power generation.
Although the wind power generation process is extremely environmentally friendly, but the lack of stability of wind power generation makes the wind power generation than other energy sources to generate high cost, so to control the wind turbine power generation, so that it follows the changes in the wind to obtain the limit of power generation to reduce costs must be accurately and timely measurement of the wind direction and speed of the wind in order to wind turbine control accordingly; In addition, the location of wind farms also requires wind speed and wind direction to have a In addition, the siting of wind farms also requires an advance prediction of wind speed and direction to provide a reasonable basis for analysis. Therefore, the use of wind speed and wind direction sensors to accurately measure the wind parameters in wind power generation is crucial.
Second, the principle of wind speed and wind direction sensor
1, mechanical wind speed and wind direction sensor
Mechanical wind speed and wind direction sensor due to the existence of mechanical shaft, so it is divided into wind speed sensor and wind direction sensor two devices:
Wind speed sensor
Mechanical structure of the wind speed sensor is a kind of use can continuously measure the wind speed and wind volume (wind volume = wind speed × cross-sectional area) size of the sensor. The more common wind speed sensor is the wind cup wind speed sensor, which is rumored to have been first invented by Robinson in England. The measuring part consists of three or four hemispherical wind cups, which are mounted at equal angles in one direction on a rotating support that is perpendicular to the ground.
Wind Sensor
Wind Sensor is a physical device that detects and senses the wind direction information of the outside world by the rotation of the wind arrow, and transmits it to the coaxial code disk, and outputs the numerical value corresponding to the wind direction; the main body of it adopts the mechanical structure of the wind vane, and when the wind blows towards the tail of the vane, the arrow of the vane points to the direction of the wind blowing towards the vane. In order to maintain the sensitivity of the direction, but also use different internal mechanisms to give the wind speed sensor to identify the direction.
2,Ultrasonic wind speed and direction sensor
The working principle of ultrasonic wave is to use ultrasonic time difference method to realize the measurement of wind speed and direction. Because the sound propagation speed in the air, and the wind direction will be superimposed on the air velocity. If the propagation direction of the ultrasonic wave is the same as the wind direction, then its speed will be accelerated; on the contrary, if the propagation direction of the ultrasonic wave if the opposite direction of the wind direction, then its speed will be slowed down. Therefore, under fixed detection conditions, the speed of ultrasonic wave propagation in the air can correspond to the wind speed function. The precise wind speed and direction can be obtained by calculation. Since the speed of the sound wave propagating in the air is greatly affected by the temperature; the wind speed sensor detects two opposite directions on two channels, so the effect of temperature on the speed of the sound wave is negligible.
Wind speed and wind direction sensors, as an indispensable and important part of wind power development, directly affect the reliability of the wind turbine and power generation efficiency, but also directly related to the wind power industry's profits, profitability, satisfaction. At present, most of the wind power plants are located in the field in the harsh natural environment, low temperature, sand and dust environment, the working temperature of the system and resistance to folding requirements are very demanding. Existing mechanical products are slightly lacking in this regard. For this reason, ultrasonic wind speed and direction sensors in the wind power industry or a broad application prospects.