WO2013044848A1

WO2013044848A1 - Calibration system and calibration method for heliostat in solar power station

Info

Publication number: WO2013044848A1
Application number: PCT/CN2012/082325
Authority: WO
Inventors: 孙海翔; 朱亮
Original assignee: Sun Haixiang
Priority date: 2011-09-29
Filing date: 2012-09-28
Publication date: 2013-04-04
Also published as: CN102354227B; CN102354227A

Abstract

A calibration system for a heliostat in a solar power station and a calibration method for the calibration system. The calibration system comprises: a receiver (1); a heliostat field mounted around the receiver (1); an image sensor group for capturing and calibrating a reflected light spot irradiated on a heliostat (2) by a light source; and a control unit. The image sensor group is movably arranged in the heliostat field. The control unit controls rotation of the heliostat (2), so that a reflected image of the heliostat (2) falls in a collection range of the image sensor group, the image sensor group moves to obtain a central position of a light spot reflected by the heliostat (2), and finally an error value required for calibration of the heliostat (2) is obtained. In the calibration system, the image sensor group moves to determine the central position of the reflected light spot of the heliostat, the calibration action is quick, the mechanical error is small, and the calibration accuracy is improved.

Description

Description of the heliostat calibration system and calibration method for solar power stations

The invention belongs to the field of solar power generation, and particularly relates to a heliostat calibration system and a tracking method for a solar power station.

Background technique

In a central tower receiver power station, the receiver at the top of the tower receives sunlight from the heliostat group. The receiver converts incident radiant energy to output high-pressure, high-temperature steam, which can then be sent to a turbine for electrical power generation. Heliostats are typically installed on the ground around the tower. Each heliostat has a rigid reflective surface that tracks the sun, and the surface uses a sunny position during the day to keep the reflected sunlight moving to the receiver. It is necessary to track the sun with high accuracy and reduce the reflected light that overflows around the receiver. Therefore, it is a technical problem that the field personnel need to solve in order to provide a heliostat calibration system capable of accurately tracking the sun to achieve a small loss.

In order to solve the above problems, the conventional calibration method for the heliostat calibration system is as follows: The image sensor detects the spatial position of the spot reflected by the heliostat, that is, the center position of the spot, and the rotation of the corresponding heliostat. Angle, where the rotation angle is the pitch angle Φ and the angle of the specified 曰 mirror, the error value of the calibration required by the heliostat is obtained, and the parameters of the heliostat in the database are updated according to the obtained error value, according to These parameters, along with the position of the receiver and the sun, calculate the angle at which the heliostat reflects the sunlight on the receiver and begins tracking.

For example, Chinese Patent No. CN101918769A discloses a heliostat calibration and tracking control method in a central tower receiver solar power plant, which includes a heliostat field that reflects sunlight to a receiver, and a camera that points to a mirror group of at least a certain day. . The camera is configured to produce multiple sunlight images that are reflected by the heliostats. The system is calibrated by the above calibration method. During the calibration process, the process of determining the center position of the spot is as follows: First, the spot reflected by the heliostat is captured by the camera, and the heliostat is in the initial configuration, in order to enable the camera to find the center position of the reflected spot of the fixed mirror, the control system controls The heliostat rotates, eventually turning the heliostat to the position where the camera captures the center of the spot. Figure 1 is a trajectory diagram of the heliostat rotation performed when the spot center sample is obtained using a camera. The orientation of the heliostat is controlled by two rotation angles, a pan angle ω and a pitch angle (?. pan angle ω along the horizontal axis The pitch angle φ is represented along the vertical axis. It can be concluded from the trajectory map that the system needs multiple rotations of the heliostat to reach the position where the camera can detect the center of the spot. The control scheme is complicated and the calibration action is slow; The multiple trajectory rotation of the frog mirror introduces mechanical errors, and the calibration accuracy is reduced. Increasing the camera can obtain the heliostat spot, but the cost of such a system will greatly increase the force. For example, in the US patent US20100139644, although calibration, The trajectory of the heliostat is simplified compared to CN101918769A. However, in order to obtain the position of the speckle spot reflected by the heliostat, it is still necessary to control the rotation of a large number of heliostats by the control system to enable the camera to capture the position of the center of the spot.

Summary of the invention

Therefore, the technical problem to be solved by the present invention is that the calibration operation of the existing heliostat calibration system is slow, and a heliostat calibration system capable of high calibration accuracy, fast calibration speed, and low running cost is provided. .

To achieve the above object, a heliostat calibration system for a solar power plant of the present invention includes: a receiver for receiving sunlight reflected by a fixed mirror; and a heliostat field composed of at least one heliostat: It is mounted around the receiver; an image sensor group consisting of at least one image sensor: a calibration light source reflection image for collecting heliostats; and a control unit: for processing the image sensor group Description

The obtained image information, and calibrating the parameters of the heliostat tracking the sun while controlling the rotation of the heliostat; the image sensor group is movably set within the field of the heliostat.

The reflected image of the heliostat collected by the image sensor group is a spot for obtaining a contour of the heliostat reflection spot; the control unit controls the rotation of the heliostat to make the reflected image of the heliostat fall And entering the image sensor group acquisition range; and obtaining the spot center position reflected by the heliostat by the movement of the image sensor group, and finally obtaining an error value of the calibration required by the heliostat.

The image acquisition range of the image sensor group is isolated from the receiving range of the receiver.

The image sensor is mounted on a planar mounting bracket, the image sensors are arranged in a horizontal direction, and the planar mounting bracket is mounted up and down on a support tower of the receiver.

The image sensor group is an image sensor, and the image sensor moves in a horizontal direction along a plane mounting bracket, which moves up and down with the plane mounting bracket.

The image sensor group is a plurality of image sensors mounted on the heliostat field mounting brackets that move up and down along the mounting brackets.

The image sensor group is provided with a dimming device for attenuating the light intensity, the dimming device comprising a light reflecting means and/or a light absorbing means.

The dimming device is a dimming device with adjustable dimming intensity.

The image sensor group is provided with a shading device for shielding sunlight.

The image sensor group is configured with a light intensity sensor for measuring light intensity.

The image sensor group is provided with a cooling device, which is an air-cooled or water-cooled device.

The heliostat is configured with two rotating shafts, and the heliostat performs a pitch rotation and a panning rotation about the rotating shaft; the double rotating shaft is equipped with an angle sensor for accurately measuring two rotating shafts. The actual angle.

The heliostat is configured with two rotating shafts, and the heliostats respectively perform pitch rotation about two rotating shafts; the double rotating shaft is provided with an angle sensor for accurately measuring the actual rotation of the two rotating shafts angle.

The calibration system also includes a day-of-day tracking sensor for tracking the sun position in real time.

The calibration system also includes a position sensor mounted on the moving track of the image sensor group for determining the position of the receiver and the image sensor.

The calibration source is a solar light source or an artificial light source.

The invention also discloses a calibration method for applying the heliostat calibration system of the above solar power station, comprising the following steps: a. The control unit controls the rotation of the heliostat to make the position of the reflection spot of the heliostat fall into The image sensor group acquires a range; b. the image sensor group collects a reflected image of the heliostat, and the control unit determines a spot center position and a corresponding heliostat according to the spot detected by the image sensor group, and passes through the Deriving the measured value of the angle sensor or the command of the control unit to obtain the rotation angle of the fixed mirror;

c control unit controls the rotation of the heliostat, so that the reflected spot of the heliostat reaches the position that the image sensor can detect; d. repeats at least n/2 times step bc according to the number n of error values to be calibrated;

e. Calculate the error value of the required calibration based on the obtained spot center position and the rotation angle information of the heliostat, and store the corrected error value to the control unit. Instruction manual

The image sensor group of step b acquires a reflection image of the heliostat by moving up or down or rotating, so that at least a part of the reflection image of the heliostat to be calibrated falls within the collection range of the image sensor group. .

The above technical solution of the present invention has the following advantages over the prior art:

(1) The present invention determines the center position of the reflected spot of the heliostat by first rotating the heliostat to a position where the reflected spot is at the image acquisition range of the sensor, which is compared with the prior art by the movement of the image sensor group. In the manner in which the center of the heliostat is aligned with the image sensor by the rotation of the heliostat, and finally the image sensor captures the center position of the spot, the calibration action of the present invention is fast, the mechanical error is small, and the calibration accuracy is improved.

(2) In addition, the present invention collects all the heliostat reflection spots in the heliostat field by means of less image sensor movement, which improves the calibration without increasing the cost compared with the prior art. Accuracy; At the same time, the image acquisition range covered by the moving track of the image sensor group is isolated from the acceptance range of the receiver for implementing calibration and power generation step by step.

(3) The calibration light source of the present invention can be selected from sunlight or artificial light source, and can be calibrated by sunlight on a sunny day, and the artificial light source can also be calibrated on a cloudy or nighttime.

DRAWINGS

In order to make the content of the present invention easier to understand, the present invention will be further described in detail below with reference to the accompanying drawings

1 is a trajectory diagram of a heliostat rotation performed when a camera is used to obtain a spot center sample in the prior art;

2 is a schematic view of a heliostat calibration system in Embodiment 1;

Figure 3 is a spot diagram obtained when the image sensor is moved;

4 is a schematic structural view of an image sensor having a dimming device;

Figure 5 is a schematic structural view of an image sensor having a light reducing device and a light blocking device;

Figure 6 is a flow chart of the information flow of the control unit;

Figure 7 is a schematic view of a heliostat calibration system of Embodiment 2;

Figure 8 is a schematic illustration of the heliostat calibration system of Embodiment 3.

The reference numerals in the figure are indicated as:

1-receiver 2 - heliostat 3 - image sensor 4 - mounting bracket 5 - dimming device 6 - solar light source 9 - support tower 10 - plane mounting bracket 12 - day tracking sensor 13 - light intensity sensor 14, 14 '-Motor 15 - Cooling device 51 - Light reduction disc 52 - Shading device

detailed description

The invention will be further illustrated by the following examples in conjunction with the accompanying drawings.

Example 1

2 shows a heliostat calibration system for a solar power plant, comprising a receiver 1 mounted on a support tower 9, the receiver 1 receiving sunlight reflected by the heliostat 2 to directly generate steam or electricity; The height of the receiver 1 from the ground ensures that the heliostats 2 in the heliostat field can be reflected onto the receiver 1.

Also included is a heliostat field mounted around the receiver; the heliostat field includes at least one heliostat 2; the heliostat 2 is configured with two axes of rotation, and the heliostat 2 is wound The rotating shaft performs a pitching rotation and a panning rotation; the double rotating shaft is provided with an angle sensor, Instruction manual

It is used to accurately measure the actual pitch angle φ and the pan angle ω of the two rotating shafts. The heliostat 1 tracks the moving sun by adjusting the mirror orientation so that the sunlight is continuously reflected onto the receiver 1. In this embodiment, the heliostat field is disposed on the receiver 1 and an image sensor group for capturing a reflected spot of the calibration light source on the heliostat 1 , the image sensor group including at least one image sensor 3. The calibration light source in this embodiment is a solar light source 6, the image sensor 3 is a camera mounted on the plane mounting bracket 10, and the plane mounting bracket 10 is located on the support tower 9 of the receiver 1, the image The sensors are arranged in a horizontal direction that moves up and down with the planar mounting bracket 10. The range of movement of the planar mounting bracket 10, i.e., the acquisition range of the image sensor, is isolated from the acceptance range of the receiver 1.

In this embodiment, the image sensor group is provided with a dimming device 5 for reducing the light intensity; the dimming device 5 is a combination of a light reflecting device and a light absorbing device for protecting the image sensor group from strong light. . The degree of dimming of the dimming device 5 in this embodiment is variable. As shown in FIG. 4, the dimming device 5 includes a dimming disk 51 which is disposed in front of the image sensor 3 and is circumferentially Divided into six blocks, each of which has a different dimming rate, the light intensity sensor 13 detects that the light intensity is strong, and the control motor 14 rotates the dimming disk 51 to a block having a high dimming rate; the light intensity sensor 13 detects the light. Stronger and weaker, the control motor 14 rotates the dimming disk 51 to a block having a low dimming rate.

More preferably, a light blocking device 52 coaxial with the dimming disc 51 may be disposed in front of the dimming disc 51, as shown in FIG. The shading device 52 is provided with a light-passing hole to allow all sunlight to pass through, and the other portion shields all sunlight. In operation, the shading device 52 is continuously rotated by the motor 14', asynchronously with the dimming disc 51, and the image sensor completes the acquisition when the light passing hole is aligned with the image sensor. The shading device 52 can reduce the exposure time and further reduce the effect of strong light on the image sensor.

The image sensor group is also provided with a cooling device 15, which is an air-cooled or water-cooled device for preventing damage to the image sensor passing through the receiver due to heat radiation.

The calibration system also includes a day-of-day tracking sensor 12 for tracking the sun position in real time to obtain a solar ray vector.

The calibration system also includes a control unit. As shown in FIG. 6, the control unit receives the heliostat image information collected by the image sensor group, the position information of the image sensor 3 collected by the position sensor, the position information of the sunlight collected by the day tracking sensor 12, and the position information collected by the angle sensor. The heliostat 2 rotates the angle information; and controls the movement of the image sensor 3 and the rotation of the heliostat 2. The control unit controls the rotation of the heliostat 2, the image sensor group 3 collects an image of the heliostat reflection spot, and the control unit determines the heliostat according to image information collected by the image sensor group. 2 The center position of the reflected spot is calibrated for the heliostat 2.

The control unit obtains a spot center position reflected by the heliostat by continuous movement of the image sensor group. When the serial image sensor group is used 30 seconds from the one end of the guide rail to the other end, the two-dimensional map shown in Fig. 3 can be obtained, which reflects the image sensor that can capture the reflected spot in the entire time period. According to this figure, the spatial position of the center of the reflected spot, that is, the centroid position of the spot map, can be derived.

The calibration system obtains the rotation angle of the heliostat through an angle sensor mounted on the rotation axis of the heliostat, that is, the pitch angle φ and the pan angle ω information, thereby obtaining the error value of the calibration required for the heliostat. . Wherein, the pitch angle φ of the heliostat is the rotation angle of the heliostat about the axis parallel to the horizontal plane, and the panning angle of the heliostat is the angle of rotation of the heliostat about the axis perpendicular to the horizontal plane.

In the calibration of heliostats, first determine the error that needs to be calibrated. The errors that need to be calibrated in this embodiment are: pitch angle and panning angle (φ., ω ₀ ), non-perpendicularity of the two rotating axes i, heliostat The spatial position (x, y, z) of the center 0 of the mirror, and the coordinate system of the heliostat itself relative to the global coordinate system Description

Three Euler corners ( ₀ 13. ^.). In other embodiments, more error parameters can be introduced to improve calibration accuracy.

Wherein, the pitch angle φ of the heliostat is the rotation angle of the heliostat about the axis parallel to the horizontal plane, and the panning angle of the heliostat is the rotation angle of the heliostat about the axis perpendicular to the horizontal plane, the center of the heliostat The position is the position coordinate (x, y, z) of the mirror center of the heliostat, and the non-perpendicular error II of the rotation axis is the actual angle of the two rotation axes. The Euler angle (α., β., γ.) is The off-angle of the heliostat's own coordinate system relative to the three coordinate axes of the global coordinate system.

The calibration method of the heliostat calibration system includes the following steps according to the error of the required calibration:

a control unit controls the rotation of the heliostat to cause the position of the reflected spot of the heliostat to fall into the image sensor group acquisition range; b. the image sensor group moves once from top to bottom, and the image sensor group detects To the spot reflected by the heliostat, the control unit determines the spot center position of the fixed mirror, and obtains the pitch angle and the pan angle of the heliostat through the angle sensor;

c. The control unit controls the rotation of the heliostat so that the reflected spot of the heliostat reaches a position detectable by the image sensor; d. repeats step bc five times to obtain five sets of spot center positions and heliostat pitch angles and Pan angle value;

e. Calculate the error value of the required calibration based on the above five sets of data: the pitch angle error, the pan angle error, the rotation non-perpendicular error, the heliostat center position error, and the Euler angle error, and The above error value is stored to the control unit. The above error calibration formula is:

g:; . , ~ ⁸ ',. where ω is the panning angle of the heliostat rotating around the axis of rotation;

φ is the pitch angle of the heliostat rotating about the axis of rotation;

a unit vector that is perpendicular to the horizontal plane;

£ is the sun light ray vector;

k is the position coordinate of the spot center;

0 is the coordinate of the center position of the mirror surface of the heliostat.

In order to improve the calibration accuracy, more steps bc can be repeated to obtain more sets of spot center position and heliostat pitch angle and pan angle value. According to multiple sets of data, the error value of the required calibration is calculated by the error calibration formula. .

Example 2

FIG. 7 shows a heliostat calibration system of the present embodiment, which is different from the calibration system of the first embodiment in that: one image sensor of the embodiment is mounted on the planar mounting bracket 10. It moves horizontally along the planar mounting bracket 10 and can move up and down with the planar mounting bracket 10. The range of movement of the planar mounting bracket 10, i.e., the acquisition range of the image sensor, is isolated from the receiving range of the receiver 1.

When the heliostat error is small, it is only necessary to calibrate the pitch angle and the roll angle error of the heliostat. In this embodiment, the error that needs to be calibrated is: the pitch angle and the roll angle error of the fixed mirror, and the calibration process of the heliostat calibration system includes the following steps:

a control unit first controls the rotation of the heliostat to cause the position of the reflected spot of the heliostat to fall into the collection range of the image sensor group;

b. The image sensor moves from left to right, then moves down a distance and then moves from right to left; making the image sensor move track Description

In a zigzag shape, the image sensor has a larger imaging range than the reflected image of the heliostat to be calibrated; c the image sensor group collects the spot reflected by the heliostat, and the control unit determines the spot center position of the heliostat, At the same time, the pitch angle and the pan angle of the heliostat are obtained;

d. The control unit controls the heliostat rotation such that the reflected spot of the heliostat reaches a position detectable by the image sensor: e. the image sensor group moves a second time from the lower portion of the receiver to the upper portion of the receiver: The image sensor moves from left to right, then moves upward by a distance, and then moves from right to left; the image sensor's movement trajectory is zigzag, the control unit determines the new spot center position, and the measurement by the angle sensor is worth a pitch angle and a pan angle to the heliostat;

f. Calculate the error value of the desired calibration by the calibration formula described in Example 1 based on the above two sets of data: pitch angle error, pan angle error and store the calibrated error value to the control unit.

The error value of the Euler angle (^, . . . , ^), the error value of the spatial position (x, y, z) of the center ₀ of the heliostat mirror, and the non-perpendicularity η of the two rotation axes. The error value calls the stored value in the control unit.

The calibration error in this embodiment is obtained by the two sets of spot position data obtained by the image sensor and the pitch angle and panning angle data of the heliostat, and the calibration accuracy is high. It should be readily apparent to those skilled in the art that the above calibration error can also be obtained from a set of spot position data obtained by one movement of the sensor and the pitch angle and pan angle data of the heliostat.

Example

FIG. 8 is a calibration system in the embodiment, which is substantially identical to the calibration system of Embodiment 1. The difference is that: the image sensor group is three groups, and the mounting bracket 4 is mounted in the heliostat field. The upper two sets of image sensors move up and down along the mounting bracket 4. Also included is a set of image sensors mounted on the planar mounting bracket 10, the planar mounting bracket 10 being located on the support tower 9 of the receiver 1, the image sensors being arranged in a horizontal direction with the planar mounting bracket 10 move up and down. In this embodiment, three sets of image sensors can calibrate image sensors in different areas of the heliostat field.

In this embodiment, the errors that need to be calibrated are: the pitch angle and the pan angle (ω _{φ ΰ} ), the spatial position (x, y, z) of the center 0 of the non-perpendicular heliostat mirror of the two rotating axes, and the date mirror coordinate system relative to its own global coordinate system of the three Euler angle (cr _¾ | 3 _q). The calibration process of the heliostat calibration system includes the following steps:

a control unit first controls the rotation of the heliostat to cause the reflected spot position of the heliostat to fall into the collection range of the image sensor group mounted on the plane mounting bracket 10;

b. The image sensor moves from top to bottom, the image sensor group detects the spot reflected by the heliostat, the control unit determines the spot center position of the heliostat, and obtains the heliostat through the measured value of the angle sensor The pitch angle and the pan angle; c control unit controls the rotation of the heliostat to make the reflected spot of the heliostat reach the position detectable by the image sensor; d. repeating step bc 9 times to obtain 9 sets of data, Calculate the error value of the required calibration according to the calibration formula described in Embodiment 1: pitch angle error, pan angle error, non-perpendicular error of the rotating axis, space position error of the heliostat mirror center 0, and Euler angle error, and The calibrated error value is stored to the control unit.

For the setting position of different calibration light sources, it is also possible to select the two sets of image sensors to collect the reflected light spot of the calibration light source of the heliostat. In this case, the control unit first controls the rotation of the heliostat to make the predetermined The reflected spot position of the day mirror falls within the acquisition range of the image sensor group mounted on the mounting bracket 4, and then the reflected spot of the heliostat is collected by the movement of the image sensor, and the control unit determines the spot center of the heliostat. After the position, the heliostat is calibrated. Instruction manual

It is apparent that the above-described embodiments are merely illustrative of the examples, and are not intended to limit the embodiments. Other variations or modifications of the various forms may be made by those skilled in the art in light of the above description. There is no need and no way to exhaust all of the implementations. Obvious changes or variations resulting therefrom are still within the scope of the invention.

Claims

Quanhe ij 8 request

A heliostat calibration system for a solar power plant, comprising:

a receiver (1), the receiver (1) for receiving sunlight reflected by the heliostat;

a heliostat field consisting of at least one heliostat (2): mounted around the receiver;

An image sensor group composed of at least one image sensor (3): a calibration light source reflection image for collecting heliostats; and a control unit: for processing image information obtained by the image sensor group, and calibrating parameters of the heliostat tracking the sun Simultaneously controlling the rotation of the fixed mirror; it is characterized by:

The image sensor group is movably disposed within the heliostat field.

2. The heliostat calibration system of a solar power plant according to claim 1, wherein:

The reflected image of the heliostat collected by the image sensor group is a spot for obtaining a contour of the heliostat reflection spot; the control unit controls the rotation of the heliostat to make the reflected image of the heliostat fall Entering the image sensor group collection range; obtaining the spot center position reflected by the heliostat (2) by the movement of the image sensor group, and finally obtaining the calibration error of the heliostat (2) value.

3. A heliostat calibration system for a solar power plant according to claim 1 or 2, characterized in that:

The image acquisition range of the image sensor group is isolated from the reception range of the receiver (1).

4. A heliostat calibration system for a solar power plant according to claim 1 or 2, characterized in that:

The image sensor (3) is mounted on a planar mounting bracket (10), the image sensors are arranged in a horizontal direction, and the planar mounting bracket (10) is movably mounted to a support tower of the receiver (1) (9) Upper.

5. The heliostat calibration system of a solar power plant according to claim 4, wherein:

The image sensor group is an image sensor (3) that moves horizontally along a planar mounting bracket (10) that moves up and down with the planar mounting bracket (10).

6. A heliostat calibration system for a solar power plant according to claim 1 or 2, characterized in that:

The image sensor group is a plurality of image sensors (3) mounted on the heliostat field mounting bracket (4), which move up and down along the mounting bracket (4).

7. A heliostat calibration system for a solar power plant according to claims 1-6, characterized in that:

The image sensor group is provided with a dimming device (5) for attenuating the light intensity, the dimming device (5) comprising a light reflecting device and/or a light absorbing device.

8. The heliostat calibration system of a solar power plant according to claim 7, wherein:

The dimming device is a dimming device (5) with adjustable dimming intensity.

9. A heliostat calibration system for a solar power plant according to any of claims 1-8, characterized in that:

The image sensor group is provided with a shading device (52) for shielding sunlight.

10. A heliostat calibration system for a solar power plant according to any of claims 1-9, characterized in that:

The image sensor group is provided with a light intensity sensor (13) for measuring light intensity.

The heliostat calibration system for a solar power plant according to any one of claims 1 to 10, characterized in that:

12. A heliostat calibration system for a solar power plant according to any of claims 1-11, characterized in that: Quanhe ij ⁹ request

13. A heliostat calibration system for a solar power plant according to any of claims 1-12, characterized in that:

14. A heliostat calibration system for a solar power plant according to any of claims 1-13, characterized in that:

The calibration system also includes a day-of-day tracking sensor (12) for tracking the sun position in real time.

15. A heliostat calibration system for a solar power plant according to any of claims 1-14, characterized in that:

16. A heliostat calibration system for a solar power plant according to any of claims 1-15, characterized in that:

The calibration source is a solar light source (6) or an artificial light source.

17. A method of calibrating a heliostat calibration system for a solar power plant according to any of claims 1-16, characterized by the following steps:

a control unit controls the rotation of the heliostat to cause the reflected spot position of the heliostat to fall into the image sensor group acquisition range; b. The image sensor group collects a reflection image of the heliostat, the control The unit determines a spot center position and a corresponding heliostat according to the spot detected by the image sensor group, and obtains the fixed mirror rotation angle by using the measured value of the angle sensor or a command of the control unit;

c control unit controls the rotation of the heliostat, so that the reflected spot of the heliostat reaches the position that the image sensor can detect: d. repeats at least n/2 times step bc according to the number n of error values to be calibrated;

e. Calculate the error value of the required calibration based on the obtained spot center position and the rotation angle information of the heliostat, and store the calibrated error value to the control unit.

18. The heliostat calibration method of a solar power plant according to claim 17, wherein:

The image sensor group of step b acquires a reflection image of the heliostat by moving up or down or rotating, so that at least a portion of the heliostat reflection image to be calibrated falls within the collection range of the image sensor group.