阅读说明：本技术 一种风力发电机前置风速管测量风向的方法 (Method for measuring wind direction of wind driven generator with preposed wind speed pipe ) 是由 沈观清 春燕 于 2021-01-27 设计创作，主要内容包括：本发明公开了一种风力发电机前置风速管测量风向的方法,包括以下步骤：在风机中心前安装前置风速管,该前置风速管是经过改进的皮托管,用于获得风车前来风气流的准确风速和风向；按照设定的风速管测定沿风速管周向分布小孔静压的测定位置,并且在特定的风速管转动到设定的角度时进行快速测量；所述测量包括测量所有动压、静压；确认测量结果的有效性；把有效的测量数据送中心计算机进行数据修正；确定风机前来流风和当前风机轴线的夹角,就是风向角；送风向角到转动风机的执行机构去转动机舱对准风向。本发明通过测定每个小孔和来流风形成的夹角以及周向的不同的静压力分布,给风机执行机构提供合理的风向指标,有效提高了风机的发电效率。(The invention discloses a method for measuring wind direction by a preposed wind speed pipe of a wind driven generator, which comprises the following steps: a front air speed pipe is arranged in front of the center of the fan, and the front air speed pipe is an improved pitot tube and is used for obtaining the accurate air speed and the accurate wind direction of the wind flow in front of the fan; measuring the measuring positions of the static pressure of the small holes distributed along the circumferential direction of the wind speed pipe according to the set wind speed pipe, and quickly measuring when the specific wind speed pipe rotates to a set angle; the measurement comprises measuring all dynamic pressure and static pressure; confirming the validity of the measurement result; sending the effective measurement data to a central computer for data correction; determining an included angle between the wind coming from the front of the fan and the axis of the current fan, namely a wind direction angle; the wind direction angle is sent to an actuating mechanism of a rotating fan to rotate the cabin to align the wind direction. The invention provides reasonable wind direction indexes for the fan actuating mechanism by measuring the included angle formed by each small hole and the incoming wind and different circumferential static pressure distributions, thereby effectively improving the generating efficiency of the fan.)

1. A method for measuring wind direction by a preposed wind speed pipe of a wind driven generator is characterized by comprising the following steps: the method comprises the following steps:

the method comprises the following steps that firstly, a front air speed pipe is installed in front of the center of a fan, and the front air speed pipe is an improved pitot tube and is used for obtaining accurate air speed and accurate air direction of wind current in front of the fan;

step two, measuring the measuring position of the static pressure of the small holes distributed along the circumferential direction of the wind speed pipe according to the set wind speed pipe, and quickly measuring when the specific wind speed pipe rotates to a set angle; the measurement comprises measuring all dynamic pressure and static pressure;

step three, confirming the validity of the measurement result;

step four, sending the effective measurement data to a central computer for data correction;

determining an included angle between the forward wind flow of the fan and the current fan axis, namely a wind direction angle;

and sixthly, supplying air to an actuating mechanism of the rotating fan to rotate the cabin to align the wind direction.

2. The method for measuring the wind direction of the wind driven generator front wind speed pipe according to claim 1, is characterized in that: according to the improved pitot tube obtained in the first step, the front row and the rear row of small holes which are uniformly distributed are formed in the side face of the outer tube of the pitot tube, the front row of small holes are used for measuring the wind speed of the wind speed tube and are called wind speed measuring small holes, the rear row of small holes are used for measuring the static pressure distribution in the circumferential direction of the wind speed tube and are called static pressure measuring distribution small holes, bent tubes are respectively inserted into the plurality of static pressure measuring distribution small holes, and each bent tube extends to the central computer along the axial direction of the wind.

3. The method for measuring the wind direction of the wind driven generator front wind speed pipe according to claim 2, is characterized in that: the static pressure distribution pores uniformly distributed on the side surface of the pitot tube outer tube can be 8 (or more) pores which are distributed in a vertical and left-right symmetrical mode, and the static pressure distribution of the upper pores is symmetrical to the static pressure distribution of the lower air measuring pores.

4. The method for measuring the wind direction of the wind driven generator front wind speed pipe according to claim 1, is characterized in that: and step two, measuring all static pressures, including measuring the static pressure of each static pressure distribution pore, wherein the static pressure is different static pressure distributions in the circumferential direction formed by measuring the included angle between the wind speed pipe and the incoming wind, and judging the wind direction by using the distribution value and adopting a corresponding curve of a wind tunnel test to obtain the included angle between the wind direction at that time and the plane of the fan.

5. The method for measuring the wind direction of the wind driven generator front wind speed pipe according to claim 1, is characterized in that: the validity of the confirmation measurement result in the third step is as follows: if the measured static pressures of the upper hole and the lower hole of the cross are the same or the near phases are the same, the calculated wind direction angle alpha is really available, the wind direction angle alpha is corrected, and the corrected angle is used for instructing an execution mechanism to rotate a windmill cabin to correctly face wind; if the currently measured pressures of the upper hole and the lower hole of the cross are different or not nearly the same, the next measurement is performed until the same data is available, and the data can be used to obtain the correct wind angle alpha which is 0 degrees.

6. The method for measuring the wind direction of the wind driven generator front wind speed pipe according to claim 1, is characterized in that: sending the measured data of the step four to a central computer for data correction, wherein the specific process is as follows:

1) and calculating a wind direction angle, namely an included angle between the current wind direction and a fan plane, according to the measured circumferential static pressure distribution numerical value of the wind speed pipe by using a data wind direction curve obtained by a wind tunnel test, wherein the actual angle is measured.

2) According to the measured circumferential static pressure distribution value of the wind speed pipe, a theoretical wind direction angle can be calculated by utilizing an aerodynamic flow field theory, and the theoretical wind direction angle is a theoretical angle; comparing the actual angle and the theoretical angle, and adjusting each other to obtain a corrected wind direction angle; usually the measured angle is accurate enough.

7. The method for measuring the wind direction of the wind driven generator front wind speed pipe according to claim 1, is characterized in that: the sixth step is specifically as follows: and instructing a plane rotating mechanism of a paddle wheel of the fan to change the direction of the paddle wheel to align the wind direction according to the corrected alpha angle.

Technical Field

The invention belongs to the technical field of wind driven generators, and particularly relates to a device and a method for measuring wind direction by a front wind speed pipe of a wind driven generator.

Background

There is still room for improvement in the utilization of wind power generation. The most effective way to reduce the price of wind power and popularize wind power is to improve the efficiency of wind power generation. Although wind power is an unpaid and inexhaustible energy source, the effective electric quantity generated in unit time is the utilization value of wind power.

The quality of the design of the wind driven generator is the most important factor, but another important factor is the accurate and efficient utilization of wind power resources. Firstly, the windmill is aligned to the wind direction at any time, and the wind is fully utilized to generate more electric energy to generate electricity.

One of the methods for aligning a windmill with the wind direction adopted at present is to install a vane type tail wing at the tail part of the small-sized fan. For one, this is not a desirable approach for large high speed fans. Because the large fan has a large moment of inertia, the generator mechanism and weight of the generator is a large damping that attempts to turn to change the direction of the fan. Secondly, the wind vane is influenced by the airflow effect of the windmill, the wind vane is arranged at the tail part of the fan, and the wind vane cannot provide reasonable wind direction indexes for a fan actuating mechanism due to the fact that the wind direction frequently changes to cause the fluctuation of the wind vane, so that the power generation efficiency of the fan is obviously influenced.

Disclosure of Invention

The invention provides a method for measuring wind direction by a front wind speed pipe of a wind driven generator, aiming at solving the problems that the wind vane is arranged at the tail part of a fan, the wind vane swings due to the large rotational inertia of a large fan and the influence of the airflow effect of a windmill on the wind vane, so that a reasonable wind direction index cannot be provided for a fan actuating mechanism and the power generation efficiency of the fan is influenced.

The invention adopts the following technical scheme for solving the problems in the prior art:

a method for measuring wind direction by a preposed wind speed pipe of a wind driven generator is characterized by comprising the following steps: the method comprises the following steps:

the method comprises the following steps that firstly, a front air speed pipe is installed in front of the center of a fan, and the front air speed pipe is an improved pitot tube and is used for obtaining accurate air speed and accurate air direction of wind current in front of the fan;

step two, measuring the measuring position of the static pressure of the small holes distributed along the circumferential direction of the wind speed pipe according to the set wind speed pipe, and quickly measuring when the specific wind speed pipe rotates to a set angle; the measurement comprises measuring all dynamic pressure and static pressure;

step three, confirming the validity of the measurement result;

step four, sending the effective measurement data to a central computer for data correction;

determining an included angle between the forward wind flow of the fan and the current fan axis, namely a wind direction angle;

and sixthly, supplying air to an actuating mechanism of the rotating fan to rotate the cabin to align the wind direction.

According to the improved pitot tube obtained in the first step, the front row and the rear row of small holes which are uniformly distributed are formed in the side face of the outer tube of the pitot tube, the front row of small holes are used for measuring the wind speed of the wind speed tube and are called wind speed measuring small holes, the rear row of small holes are used for measuring the static pressure distribution in the circumferential direction of the wind speed tube and are called static pressure measuring distribution small holes, bent tubes are respectively inserted into the plurality of static pressure measuring distribution small holes, and each bent tube extends to the central computer along the axial direction of the wind.

The static pressure distribution pores uniformly distributed on the side surface of the pitot tube outer tube can be 8 (or more) pores which are distributed in a vertical and left-right symmetrical mode, and the static pressure distribution of the upper pores is symmetrical to the static pressure distribution of the lower air measuring pores.

And step two, measuring all static pressures, including measuring the static pressure of each static pressure distribution pore, wherein the static pressure is different static pressure distributions in the circumferential direction formed by measuring the included angle between the wind speed pipe and the incoming wind, and judging the wind direction by using the distribution value and adopting a corresponding curve of a wind tunnel test to obtain the included angle between the wind direction at that time and the plane of the fan.

The validity of the confirmation measurement result in the third step is as follows: if the measured static pressures of the upper hole and the lower hole of the cross are the same or the near phases are the same, the calculated wind direction angle alpha is really available, the wind direction angle alpha is corrected, and the corrected angle is used for instructing an execution mechanism to rotate a windmill cabin to correctly face wind; if the currently measured pressures of the upper hole and the lower hole of the cross are different or not nearly the same, the next measurement is performed until the same data is available, and the data can be used to obtain the correct wind angle alpha which is 0 degrees.

Sending the measured data of the step four to a central computer for data correction, wherein the specific process is as follows:

1) and calculating a wind direction angle, namely an included angle between the current wind direction and a fan plane, according to the measured circumferential static pressure distribution numerical value of the wind speed pipe by using a data wind direction curve obtained by a wind tunnel test, wherein the actual angle is measured.

2) According to the measured circumferential static pressure distribution value of the wind speed pipe, a theoretical wind direction angle can be calculated by utilizing an aerodynamic flow field theory, and the theoretical wind direction angle is a theoretical angle; comparing the actual angle and the theoretical angle, and adjusting each other to obtain a corrected wind direction angle; usually the measured angle is accurate enough.

The sixth step is specifically as follows: and instructing a plane rotating mechanism of a paddle wheel of the fan to change the direction of the paddle wheel to align the wind direction according to the corrected alpha angle.

Advantageous effects of the invention

According to the invention, the installation position of the wind speed pipe is changed from installation at the tail part of the fan to installation at the front center of the fan, so that the wind speed pipe is far away from the influence of large rotational inertia of the large fan, and the accuracy rate of measuring static pressure is improved; by changing the shape of the wind measuring device, the wind vane (windmill shape) is changed into a wind speed pipe, so that the problem of inaccurate detection caused by the fluctuation of the wind vane due to frequent change of the wind direction is avoided; the wind speed pipe is characterized in that a row of uniformly distributed small holes for measuring the wind direction are additionally arranged on the outer side surface of the wind speed pipe, the included angle formed by each small hole and incoming wind and different circumferential static pressure distributions are measured, the wind direction is judged by adopting a corresponding curve of a wind tunnel test by utilizing the distribution value, the included angle between the current wind direction and the plane of the fan is known, the included angle is sent to a central computer by a wind measuring system to be corrected, the unexpected effect is obtained by changing the shapes, the positions and the mutual relations of the elements, reasonable wind direction indexes are provided for a fan executing mechanism, and the power generation efficiency of the fan is effectively improved.

Drawings

FIG. 1a is a front view of a front wind velocity stack according to the present invention;

FIG. 1b is a simplified front view of the improved forward air velocity stack of the present invention;

FIG. 2 is a right side view of the improved forward anemometer of the present invention;

FIG. 3 is a schematic view of measuring a wind direction angle according to the present invention;

FIG. 4 is a flow chart of a method for pre-anemometer measurement according to the present invention;

in the figure: 1: an outer tube; 2: an inner tube; 3: a small hole for measuring wind speed; 4-1: measuring a static pressure distribution small hole 4-1: and (5) measuring the static pressure distribution bent pipe.

Detailed Description

The invention is further explained below with reference to the drawings:

principle for measuring wind direction by using pitot tube

1. Improve wind measuring device and mounted position. The wind measuring device adopting the conventional wind vane type (windmill) is improved into a wind speed pipe, so that the problem of inaccurate detection caused by the fluctuation of the wind vane due to frequent change of the wind direction is solved; the wind measuring device is installed at the tail of the fan by a conventional method, and is installed at the front end of the center of the fan instead, so that the wind speed pipe is far away from the influence of the large-scale fan rotational inertia at the tail of the fan.

2. Common "pitot tube" before modification: the common pitot tube is a two-layer sleeve for measuring dynamic pressure and static pressure of incoming wind, a circle of small holes for measuring static pressure are uniformly distributed on the side surface of an outer tube of the pitot tube, when a wind speed tube is parallel to the direction of the incoming wind, the pitot tube is used for measuring the static pressure of airflow parallel to the wind direction, and the common pitot tube can only be used for measuring the wind speed.

3. Modified "pitot tube": at present, the small holes on the side surface of a common pitot tube are increased from one row to two rows, the increased small holes in one row are respectively communicated with respective wind pressure measuring small pipes to measure different static pressure distributions around a wind speed pipe, the static pressure is used for integrating flow field characteristics so as to determine the wind direction of wind flow, and the improved pitot tube can measure the wind speed and the wind direction.

To summarize: the invention adopts the improved pitot tube arranged in front of the fan, so that the accurate wind speed and wind direction of the wind flow coming in front of the fan can be obtained. The accurate wind direction can make the fan oar dish be in a reasonable angle all the time to aim at the wind direction, improve windmill generating efficiency.

4. The invention relates to a method for measuring wind direction, which is based on a wind direction measuring system of a wind driven generator front-mounted wind speed pipe. The system derives static pressure distribution data from the wind speed pipe, then connects the derived data with a central computer, and calculates an actual angle and a theoretical angle by the central computer, and compares the actual angle and the theoretical angle with each other, and obtains a corrected wind direction angle after adjusting each other.

Based on the principle, the invention designs a method for measuring wind direction by a preposed wind speed pipe of a wind driven generator, which is characterized by comprising the following steps: the method comprises the following steps:

a method for measuring wind direction by a preposed wind speed pipe of a wind driven generator is characterized by comprising the following steps: the method comprises the following steps:

the method comprises the following steps that firstly, a front air speed pipe is installed in front of the center of a fan, and the front air speed pipe is an improved pitot tube and is used for obtaining accurate air speed and accurate air direction of wind current in front of the fan;

as shown in fig. 1a, 1b, 2, 3 and 4, in the modified pitot tube in the first step, two rows of small holes which are uniformly distributed are arranged on the side surface of the outer tube of the pitot tube, the front row of small holes is used for measuring the wind speed of the wind speed tube and is called as a wind speed measuring small hole 3, the rear row of small holes is used for measuring the static pressure distribution in the circumferential direction of the wind speed tube and is called as a static pressure measuring small hole 4-1, bent pipes 4-2 are respectively inserted into the plurality of static pressure measuring small holes 4-1, and each bent pipe 4-2 extends to a central computer along the axial direction of the wind speed tube.

The static pressure distribution measuring small holes 4-1 uniformly distributed on the side surface of the pitot tube outer tube can be 8 (or more) small holes which are distributed in a vertical and left-right symmetrical mode, and the static pressure distribution of the upper holes is symmetrical to the static pressure distribution of the lower air measuring holes.

Step two, measuring the measuring position of the static pressure of the small holes distributed along the circumferential direction of the wind speed pipe according to the set wind speed pipe, and quickly measuring when the specific wind speed pipe rotates to a set angle; the measurement comprises measuring all dynamic pressure and static pressure;

and step two, measuring all static pressures, including measuring the static pressure of each static pressure distribution measuring small hole 4-1, wherein the static pressure is circumferential different static pressure distributions formed by measuring an included angle between the wind speed pipe and the incoming wind, and judging the wind direction by using a corresponding curve of a wind tunnel test according to the distribution value to obtain the included angle between the current wind direction and the plane of the fan.

Step three, confirming the validity of the measurement result;

the validity of the confirmation measurement result in the third step is as follows: if the measured static pressures of the upper hole and the lower hole of the cross are the same or the near phases are the same, the calculated wind direction angle alpha is really available, the wind direction angle alpha is corrected, and the corrected angle is used for instructing an execution mechanism to rotate a windmill cabin to correctly face wind; if the currently measured pressures of the upper hole and the lower hole of the cross are different or not nearly the same, the next measurement is performed until the same data is available, and the data can be used to obtain the correct wind angle alpha which is 0 degrees.

Step four, sending the effective measurement data to a central computer for data correction;

sending the measured data of the step four to a central computer for data correction, wherein the specific process is as follows:

1) and calculating a wind direction angle, namely an included angle between the current wind direction and a fan plane, according to the measured circumferential static pressure distribution numerical value of the wind speed pipe by using a data wind direction curve obtained by a wind tunnel test, wherein the actual angle is measured.

2) According to the measured circumferential static pressure distribution value of the wind speed pipe, a theoretical wind direction angle can be calculated by utilizing an aerodynamic flow field theory, and the theoretical wind direction angle is a theoretical angle; comparing the actual angle and the theoretical angle, and adjusting each other to obtain a corrected wind direction angle; usually the measured angle is accurate enough.

Determining an included angle between the forward wind flow of the fan and the current fan axis, namely a wind direction angle;

and sixthly, supplying air to an actuating mechanism of the rotating fan to rotate the cabin to align the wind direction.

The sixth step is specifically as follows: and instructing a plane rotating mechanism of a paddle wheel of the fan to change the direction of the paddle wheel to align the wind direction according to the corrected alpha angle.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention; it should be noted that modifications and embellishments within the scope of the invention may occur to those skilled in the art without departing from the principle of the invention, and are considered to be within the scope of the invention.