CN202075303U - Micro differential pressure type high precision wind measurement apparatus - Google Patents

Abstract

The utility model discloses a micro-differential pressure type high-precision wind measuring device. The wind measuring device of the utility model comprises a pitot tube, a differential pressure sensor, a data acquisition and processing unit, and a fixed bracket. The device uses four pitot tubes perpendicular to each other in the horizontal direction as wind measuring probes, uses four supporting high-precision differential pressure sensors to detect the output of each pitot tube, and uses the data acquisition and processing unit to convert the output of the sensor into differential pressure. pressure value. The utility model has no movable parts, avoids the problems of mechanical wear and the like when relying on the rotating parts to measure the wind speed and direction, and has the characteristics of good instantaneity, high precision, long life, good reliability and less influence by the environment.

Description

A micro-differential pressure type high-precision wind measuring device

technical field

The utility model relates to a micro-differential pressure type high-precision wind measuring device, which belongs to the technical field of meteorological observation.

Background technique

The measurement of wind speed and wind direction provides data for accurate weather forecast and early warning, and provides a basis for the general survey and utilization of wind energy. At present, wind cups/wind vanes or ultrasonic anemometers are commonly used in weather stations to measure wind. Among them, when the wind cup/wind vane measures the wind, the wind cup calculates the wind speed by the number of revolutions of the wind cup within a period of time. The start-up wind speed is large, the hysteresis is large, and the gust can hardly be measured accurately. The problem of lagging wind direction; the ultrasonic wind measuring instrument has the disadvantages of high price and great influence of temperature, precipitation and snowfall.

Contents of the invention

The technical problem to be solved by this utility model is to design a kind of micro-differential pressure type high-precision wind measuring device with Pitot tube as the probe, and adopt the method of BP neural network interpolation processing to obtain the wind speed and wind direction value in view of the defects of the above background technology. It is conducive to improving the measurement accuracy of wind speed and improving the service life due to the elimination of mechanical rotating parts.

The utility model adopts the following technical solutions for solving the above-mentioned technical problems:

A micro-differential pressure high-precision wind measuring device, including four pitot tubes, four micro-differential pressure sensors, a data acquisition and processing unit, and a fixed bracket; the measuring probes of the four pitot tubes are placed vertically and horizontally in four directions On the fixed bracket, the four micro-differential pressure sensors are respectively connected to the upper ports of the four pitot tubes, and the output differential pressures of the four pitot tubes are converted into electrical signals and then input to the data acquisition and processing unit.

Further, the pitot tube of the micro-differential pressure type high-precision wind measuring device of the present invention is L-shaped, one end of which is a measuring probe, and the other end is vertically connected to the micro-differential pressure sensor.

The utility model adopts the above-mentioned technical scheme and has the following beneficial effects:

The measuring device of the utility model uses the pitot tube and the structure of the high-precision differential pressure sensor to measure the wind speed and the wind direction. It avoids the mechanical wear caused by the rotating wind direction measurement, which prolongs the working life; the ultrasonic wind measurement is greatly affected by rain, snow, freezing and other weather conditions.

Description of drawings

Fig. 1 is a structural diagram of the micro-differential pressure type high-precision wind measuring device of the present invention.

Labels in the figure: 1-pitot tube; 2-micro differential pressure sensor; 3-data acquisition and processing unit; 4-fixing bracket.

specific implementation plan

Below in conjunction with accompanying drawing, the technical scheme of utility model is described in detail:

As shown in FIG. 1 , four Pitot tubes 1 installed perpendicular to each other in the horizontal direction are used as measuring probes for wind speed and direction, and output wind total pressure and static pressure values.

High-precision micro-differential pressure sensors 2 are respectively installed on the top of the four pitot tubes, and the total pressure and static pressure generated by the pitot tubes are used as differential pressure inputs of the micro-differential pressure sensors.

The data acquisition and processing unit 3 amplifies and processes the output signal of the micro-differential pressure sensor, converts it into a digital signal, and outputs the actual differential pressure value through calibration.

The wind speed and wind direction measuring device composed of pitot tube, high-precision differential pressure sensor and data acquisition and processing unit is fixedly installed on the fixed bracket 4, and the measuring device is installed at a suitable height by using the fixed bracket.

Obtain the test data of four differential pressure sensors at the standard wind speed and wind direction. After selecting samples, use the output of the four differential pressure sensors as the input of the BP network, and the corresponding standard wind speed and wind direction as the target output of the network. The number of nodes in the input layer, hidden layer and output layer is structured according to the ratio of 4:5:2. The hidden layer adopts hyperbolic tangent s-type as the transfer function, the transfer function of the output layer neurons is purelin, and the training function used is trainscg. Set the error E=0.0001, the learning step size is 0.05, and train the network.

After the BP network training is completed, a BP network interpolation algorithm model with four inputs and two outputs is obtained.

During data processing, the pressure value measured by the differential pressure sensor is used as the input of the model, and the output of the model is the corresponding wind speed and wind direction.

The stored BP network algorithm is directly invoked by the PC to interpolate the collected data, and the corresponding program can also be written according to the mathematical expression of the BP network to be realized by the microprocessor.

The mathematical expression is as follows:

、

、

、

,阈值为

，其中下标表示α、β、γ、η与隐层中的第i个神经元的连接；输出单元风向θ和风速v到隐层单元的权值和阈值分别为 

、

、

、

，下标表示θ、v与隐层中的第i个神经元的连接；tanh为双曲正切s 型传递函数。 Among them, the readings of the four pressure sensors are α, β, γ, and η respectively, and the output wind direction θ and wind speed v after BP network interpolation processing; the weights from the hidden unit to the input unit α, β, γ, and η are respectively

,

,

,

, the threshold is

, where the subscript indicates the connection between α, β, γ, η and the i-th neuron in the hidden layer; the weight and threshold of the output unit wind direction θ and wind speed v to the hidden layer unit are respectively

,

,

,

, the subscript indicates the connection between θ, v and the i-th neuron in the hidden layer; tanh is the hyperbolic tangent s-type transfer function.

、

、

、

、

、和各阈值

、

、

即为常量，传递函数tanh可调用库函数实现，因此，对上述公式进行算法设计及编程，检测到的四个差压传感器信号α、β、γ、η作为模型的输入，则可获得模型的输出，即风速v和风向θ。 After the BP network training is completed, the weights

,

,

,

,

, and each threshold

,

,

It is a constant, and the transfer function tanh can be implemented by calling the library function. Therefore, the algorithm design and programming are carried out on the above formula, and the detected four differential pressure sensor signals α, β, γ, η are used as the input of the model, and the model can be obtained Output, namely wind speed v and wind direction θ.

The above description is only an implementation example of the present utility model, and is not intended to limit the present utility model. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present utility model shall be included in this utility model. within the scope of the new protection.

Claims (2)

1. A micro-differential pressure type high-precision wind measuring device is characterized in that: it comprises four pitot tubes, four micro-differential pressure sensors, a data acquisition processing unit and a fixed support; The two directions are vertically and horizontally placed on the fixed bracket, and the four micro-differential pressure sensors are respectively connected to the upper ports of the four pitot tubes, and the output differential pressure of the four pitot tubes is converted into electrical signals and then input to the data acquisition and processing unit. 2. The micro-differential pressure type high-precision wind measuring device according to claim 1, characterized in that: the pitot tube is L-shaped, one end of which is a measuring probe, and the other end is vertically connected to the micro-differential pressure sensor.