Ceiling type large-area light field regulation and control device and method

Abstract

The invention belongs to the technical field of light field regulation and control, and particularly relates to a ceiling type large-area light field regulation and control device and method, and the core of the device comprises a ceiling type structure, a polymer multilayer optical film, a PPFD sensor, an irradiance sensor and a microcontroller. The ceiling type structure is provided with light filter plates arranged in an array mode, a polymer light splitting film capable of selectively transmitting red light, blue light and far-red light is attached to the outer layer, and the plant growth spectrum is optimized. And the PPFD sensor and the irradiance sensor are used for respectively monitoring the flux density of internal and external photosynthetic photons and the irradiance of sunlight. The microcontroller regulates and controls the transmission device according to sensor data, adjusts the angle of the light filter plate and regulates and controls the light field in a refined mode. Through three regulation and control modes, optimal utilization of illumination is realized, normal growth of crops under extreme climate is guaranteed, and energy and grain safety challenges are effectively coped with.

Description

Technical Field

[0001] The present invention belongs to the technical field of light field regulation, and particularly relates to a ceiling-mounted large-area light field regulation device and method. Background Art

[0002] In the existing light field regulation technologies, the light management for farmlands or greenhouses mainly relies on traditional means such as sunshade nets and reflective films. To a certain extent, these methods can adjust the light intensity and light direction, but their adjustment range and accuracy are limited, and it is difficult to meet the high requirements of modern precision agriculture for the light environment.

[0003] In recent years, with the intensification of global climate change, energy and food security have become issues of increasing concern in many regions. In particular, the phenomena of extreme high temperatures and reduced precipitation caused by global warming pose a serious threat to the normal growth of crops. To improve the yield and quality of crops, it is particularly important to optimize the light environment regulation technology.

[0004] Although traditional light management means such as sunshade nets and reflective films have been applied to a certain extent in farmlands or greenhouses, they have many defects. First of all, the adjustment range and accuracy of these means are limited, and it is difficult to meet the specific requirements of different crops for the light environment at different growth stages. Secondly, traditional means often lack selectivity for the solar spectrum when adjusting the light field, resulting in some spectral components beneficial to plant growth being overly blocked or wasted. In addition, the effects of traditional means in dealing with extreme climate conditions are not good. For example, in a high-temperature and drought environment, it is difficult to effectively reduce the temperature in the greenhouse and reduce the soil water evaporation. Summary of the Invention

[0005] The purpose of the present invention is to provide a ceiling-mounted large-area light field regulation device and method, which aims to optimize the growth environment of plants by adjusting the light field, especially in the face of challenges brought about by climate change, such as extreme high temperatures and reduced precipitation caused by global warming.

[0006] The present invention realizes the above purpose through the following technical solutions:

[0007] In a first aspect, the present invention proposes a ceiling-mounted large-area light field regulation device, comprising:

[0008] A ceiling-mounted structure, including an array of filter plates and their drive devices, a polymer multi-layer optical film is attached to the outer side of the filter plate, the polymer multi-layer optical film is a multi-film layer formed by alternating high-refractive-index film layers and low-refractive-index film layers, and the polymer multi-layer optical film is used to select and transmit red light, blue light, and far-red light from sunlight for the growth of plants below the ceiling-mounted structure;

[0009] A PPFD sensor and an irradiance sensor are respectively used to monitor PPFD and solar irradiance;

[0010] A microcontroller is used to receive the PPFD and solar irradiance and regulate the transmission device to change the angle of the filter plate, adjusting the incident amount and filtering amount of sunlight.

[0011] Furthermore, the ceiling structure further includes a mounting bracket. The transmission device includes a first rotary motor disposed at the horizontal axis above the mounting bracket, and a second shaft body and a corresponding second rotary motor disposed on the mounting bracket; the filter plate is connected to the first shaft body and is used to rotate along a first preset direction under the drive of the first rotary motor; the filter plate is connected to the second shaft body and is used to rotate along a second preset direction under the drive of the second rotary motor;

[0012] Wherein, the first preset direction is used to represent the orientation angle of the filter plate, and the second preset direction is used to represent the tilt angle of the filter plate.

[0013] Furthermore, the transmission device includes a pulley set disposed on the horizontal axis and a transmission rope disposed between the pulley set and the first rotary motor, and the transmission rope passes through the middle section of the filter plate;

[0014] The first rotary motor is connected to the filter plate through the transmission rope and the pulley set, and the second rotary motor is connected to the filter plate through the shaft body to adjust the angle of the filter plate.

[0015] Furthermore, the PPFD sensors are distributed outside and below the ceiling structure to measure the external PPFD and internal PPFD respectively; the irradiance sensors are distributed outside the ceiling structure and are used to measure the solar irradiance.

[0016] Furthermore, the microcontroller receives the PPFD and solar irradiance and regulates the transmission device to implement the pre-configured filter plate regulation mode of the system, including:

[0017] The first regulation mode: when the solar irradiance is greater than a first preset value and the external PPFD > internal PPFD, the microcontroller regulates the plane of the filter plate to be perpendicular to the direct sunlight;

[0018] The second regulation mode: when the solar irradiance is less than a second preset value and the external PPFD > internal PPFD, the microcontroller regulates the plane of the filter plate to be parallel to the direct sunlight;

[0019] The third control mode adjusts the placement angle of the light filter plate according to the set target PPFD, the measured PPFD, and the solar irradiance of the crops planted under the ceiling structure to meet the set target PPFD for plant growth and minimize spectral shift.

[0020] Further, in the first control mode, the rotation angle of the second shaft body along the second preset direction is controlled to be A, the rotation angle of the first shaft body along the first preset direction is controlled to be B, and B = -sin -1 (sinθ * cosα); where α is the solar altitude angle and θ is the solar azimuth angle; the value range of A is (-90°, 0°), and the value range of B is (-90°, 90°).

[0021] Further, in the second control mode, the rotation angle of the first shaft body along the first preset direction is controlled to be B, or the rotation angle of the second shaft body along the second preset direction is controlled to be A,

[0022] Further, the microcontroller includes:

[0023] A first calculation unit for calculating the shadow area S1 generated by occlusion according to the size, height of the light filter plate in the ceiling structure, and the current rotation angles A and B of the light filter plate;

[0024] A parameter acquisition unit for acquiring the external PPFD and the internal PPFD;

[0025] A second calculation unit for calculating the rotation angles A and B that meet the target PPFD requirement according to the following formula: Pd = P1 * (S - S1) / S + P0 * S1 / S, where S is the total area of the light filter plate array, Pd is the target PPFD, P1 is the external PPFD, and P0 is the internal PPFD;

[0026] A result output unit for selecting a set of results with the shortest adjustment step from the calculated multiple sets of rotation angles A and B for angle adjustment;

[0027] The angle adjustment includes the following steps:

[0028] Fine-tune the light filter plate according to the actually measured PPFD under the plate until the target PPFD is reached;

[0029] If the actual PPFD is less than the target PPFD, then reduce the angle between the normal direction of the light filter plate and the direct sunlight;

[0030] If the actual PPFD is greater than the target PPFD, then increase the angle between the normal direction of the light filter plate and the direct sunlight.

[0031] Further, in the first calculation unit, calculating the shadow area S1 generated by occlusion includes the following steps:

[0032] Taking the center position of the light filter as the origin, the first preset direction as the x-axis, the second preset direction as the y-axis, and the direction perpendicular to the ground and upward as the z-axis to establish a space rectangular coordinate system;

[0033] Setting the length of the light filter as a meters, the width as b meters, and the installation height as c meters. The coordinates of the four vertices of the light filter are P1=(0.5a, 0.5b, 0), P2=(-0.5a, 0.5b, 0), P3=(0.5a, -0.5b, 0), and P4=(-0.5a, -0.5b, 0);

[0034] Combining the rotation angles A and B, calculating the coordinates P 1 ‘, P 2 ’, P 3 ‘, P 4 ';

[0035] Combining the real-time solar altitude angle and solar azimuth angle, calculating the projection coordinates P 1 ″, P 2 ″, P 3 ″, P 4 ″;

[0036] In the coordinate region, the shadow area S1 = S shadow (P″ 1 , P″ 2 , P″ 3 , P″ 4 ) ∩ S.

[0037] Second aspect, the present invention proposes a method for optical field regulation using the ceiling-mounted large-area optical field regulation device as described in any one of the above, including the following steps:

[0038] S1. Using a solar irradiance sensor to monitor the total irradiance at the location of the device as a reference value for the light adjustment of the overall device;

[0039] S2. Using a PPFD sensor to measure the external PPFD and internal PPFD respectively;

[0040] S3. The microcontroller receives the data of PPFD and solar irradiance and controls the transmission device to change the angle of the light filter, adjust the incident amount and filtering amount of sunlight, and achieve one of the following three regulation modes:

[0041] The first regulation mode (positive tracking mode), when the solar irradiance is greater than the first preset value and the external PPFD > the internal PPFD, the microcontroller controls the plane where the light filter is located to be perpendicular to the direct solar rays;

[0042] The second regulation mode (reverse tracking mode): when the solar irradiance is less than the second preset value and the external PPFD > the internal PPFD, the microcontroller regulates the plane where the filter plate is located to be parallel to the direct sunlight rays.

[0043] The third regulation mode (optimization mode): according to the set target PPFD of the crops planted under the ceiling structure, the measured PPFD, and the solar irradiance, the placement angle of the filter plate is adjusted to meet the set target PPFD for plant growth and minimize the spectral shift.

[0044] The beneficial effects of the present invention are as follows:

[0045] Through the filter plates arranged in an array and their transmission devices of the present invention, combined with the polymer multi-layer optical film, it can accurately select and transmit red light, blue light, and far red light to meet the lighting requirements for plant growth. At the same time, by using the PPFD sensor and the irradiance sensor to monitor the lighting situation in real time and through the intelligent regulation of the microcontroller, the fine adjustment of the angle of the filter plate is realized, thereby optimizing the incident amount and filtering amount of sunlight. This not only improves the photosynthetic efficiency of the crops but also reduces the temperature under the device and the evaporation amount of soil water, enhancing the planting ability of the agricultural greenhouse in bad weather. In addition, this device has wide applicability and can be used in large areas of farmland or greenhouses, providing strong support for achieving food security and sustainable agricultural development. Description of the Drawings

[0046] Figure 1 It is a schematic diagram of the placement positions of the PPFD sensor and the irradiance sensor in the embodiment of the present application;

[0047] Figure 2 It is a schematic diagram of the overall structure of a regulation device in the embodiment of the present application;

[0048] Figure 3 It is a schematic diagram of the structure at the connection between the transmission rope and the filter plate of a regulation device in the embodiment of the present application;

[0049] Figure 4 It is a schematic diagram of the structure at the connection between the second shaft body and the filter plate of a regulation device in the embodiment of the present application;

[0050] Figure 5 It is a schematic diagram of a structure of the filter plate in the embodiment of the present application;

[0051] Figure 6 It is a structural block diagram of the sunlight irradiation information measurement system realized based on the sensor combination in the embodiment of the present application;

[0052] Figure 7 It is a schematic diagram of the second regulation mode in the embodiment of the present application;

[0053] Figure 8 This is a schematic diagram of the first regulation mode in the embodiments of the present application.

[0054] In the figure, 1 is a photosynthetic photon flux density sensor; 2 is a solar irradiance sensor; 3 is a filter plate; 4 is a first shaft body; 5 is a second shaft body; 6 is a first rotating motor; 7 is a second rotating motor; 8 is a pulley block; 9 is a transmission rope; 10 is a bearing block; 31 is a polymer multi-layer optical film. Specific embodiments

[0055] The present application will be further described in detail below with reference to the accompanying drawings. It is necessary to point out here that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the protection scope of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0056] Embodiment 1

[0057] As Figures 1-5 shown, this embodiment proposes a ceiling-mounted large-area light field regulation device, including a ceiling-mounted structure, a PPFD sensor 1, an irradiance sensor 2, and a controller. The ceiling-mounted structure includes an array of filter plates 3 and its transmission device. A polymer multi-layer optical film 31 is attached to the outside of the filter plate 3. The polymer multi-layer optical film 31 is a multi-film layer formed by alternating stacking of high refractive index film layers and low refractive index film layers. The polymer multi-layer optical film 31 is used to select and transmit red light, blue light, and far red light from sunlight for plant growth below the ceiling-mounted structure; the PPFD sensor 1 and the irradiance sensor 2 are respectively used to monitor the PPFD (photosynthetic photon flux density) and solar irradiance; the microcontroller is used to receive the PPFD and solar irradiance (GHI) and regulate the transmission device to change the angle of the filter plate 3 and adjust the incident amount and filtering amount of sunlight.

[0058] A polymer multi-layer optical film 31 is used in the above device. This thin film can select and transmit red light, blue light, and far red light from the solar spectrum for plant growth. The above polymer multi-layer optical film 31 is obtained by a layer-by-layer multiplication co-extrusion technique. The preparation method includes the following steps:

[0059] (1) Stack two or more polymer-based melts to form a layered polymer-based melt with two or more layers;

[0060] (2) Multiply the layered polymer-based melt to obtain a multi-layer polymer-based melt;

[0061] (3) Extrude the multi-layer polymer-based melt, stretch and cool it, and wind it up to obtain the polymer multi-layer optical film.

[0062] The above-mentioned polymer multi-layer optical film 31 has at least one reflection peak in the wavelength range of 380 nm - 780 nm. The reflection peak with the maximum reflectivity in this range is the first reflection peak, and the reflectivity of the first reflection peak is 90% - 99.99%. The overall reflectivity in the wavelength range of 1100 nm - 2500 nm is 0 - 50%, and the average transmittance in the wavelength range of 380 nm - 780 nm is more than 70%.

[0063] By applying the above-mentioned polymer multi-layer optical film in this application, the temperature and water evaporation amount under the device can be effectively reduced in hot climates; the PPFD situation under the device can be optimized and regulated with high precision to meet the different lighting requirements of plants at various growth stages. Moreover, the polymer multi-layer optical film used in this application also has the advantages of low cost, strong anti-aging property, and can be prepared in large areas.

[0064] Regarding the positions of the PPFD sensor 1 and the irradiance sensor 2 in the above-mentioned device, specifically in combination with Figure 1 As shown, the PPFD sensors 1 are distributed on the outside and below the ceiling structure, measuring the external PPFD and the internal PPFD respectively; the irradiance sensors 2 are distributed on the outside of the ceiling structure for measuring the solar irradiance. Among them, the solar irradiance sensor is used to measure the irradiance of the entire wavelength band of the unobstructed sunlight, serving as a reference value for the light adjustment of the overall device; the PPFD sensors measure the external PPFD (PPFD on the ground outside the device) and the internal PPFD (PPFD under the device) respectively, aiming to regulate the PPFD under the device in combination with the lighting requirements of the crops planted under the device.

[0065] Exemplarily, the specific placement positions of the PPFD sensors 1 and the irradiance sensors 2 are as Figure 1 shown: They are respectively placed directly below the middle and the east end of the northernmost row of filter plates, directly below the middle and the east end of the middle row of filter plates, and directly below the middle and the east end of the southernmost row of filter plates.

[0066] In combination with Figure 2 , the ceiling structure is placed facing south with north, that is, the orientation angle is 180°. In a preferred embodiment of the present invention, the ceiling structure further includes a mounting bracket 4. The transmission device includes a rotary motor one 6 provided at the horizontal axis above the mounting bracket 4, and a second shaft body 5 and a corresponding rotary motor two 7 provided on the mounting bracket 4. The filter plate 3 is connected to the first shaft body 4 and is used to rotate along a first preset direction driven by the rotary motor one 6; the filter plate 3 is connected to the second shaft body 5 and is used to rotate along a second preset direction driven by the rotary motor two 7. Among them, the first preset direction is used to represent the orientation angle of the filter plate 3, and the second preset direction is used to represent the tilt angle of the filter plate 3.

[0067] Definition of the orientation angle in this application: The filter plate 3 rotates along a first preset direction through the first shaft body 4 and its corresponding rotating motor 1, and this rotation direction is defined as the adjustment of the orientation angle of the filter plate. The orientation angle refers to the included angle between the normal direction of the filter plate and the geographical north direction, and is used to adjust the direction of the filter plate facing the direct sunlight.

[0068] Definition of the tilt angle in this application: The filter plate 3 also rotates along a second preset direction through the second shaft body 5 perpendicular to the first shaft body 4 and its corresponding rotating motor 2, and this rotation direction is defined as the adjustment of the tilt angle of the filter plate 3. The tilt angle refers to the included angle between the filter plate and the horizontal plane, and is used to adjust the incident angle of the sunlight received by the filter plate.

[0069] The transmission device includes a pulley set 8 provided on the horizontal shaft and a transmission rope 9 provided between the pulley set 8 and the rotating motor 1, and the transmission rope 9 passes through the middle section of the filter plate 3; more specifically, combined with Figure 3 , the transmission rope 9 is connected to the midpoint position of the frame of the filter plate 3 through a collar and a shackle.

[0070] The rotating motor 1 is connected to the filter plate 3 through the transmission rope 9 and the pulley set 8, and the rotating motor 2 is connected to the filter plate 3 through the shaft body 5 to adjust the angle of the filter plate 3. More specifically, combined with Figure 4 , the bearing seat 10 is installed directly below the shackle, and the shaft body 5 is connected to the filter plate 3 through the bearing seat 10, and the motor 2 drives the shaft body 5 to drive the north-south rotation of the filter plate 3.

[0071] During specific implementation, a microcontroller is used to control the motor to control the angle of the ceiling-mounted structure, and the ceiling-mounted structure is used to adjust the incident amount of sunlight and the amount of light filtering, that is, the motor drives the ceiling-mounted structure to change the angle of the filter plate 3. When the angle of the filter plate changes, the filtering degree of the device for sunlight will change. It can be adjusted according to the daily sunlight irradiation situation and the crop planting needs under the device.

[0072] In a preferred embodiment of the present invention, the microcontroller receives the PPFD and the sunlight irradiance, and controls the transmission device to implement the pre-configured control mode of the filter plate 3, including:

[0073] The first control mode, when the sunlight irradiance is greater than the first preset value and the external PPFD > the internal PPFD, the microcontroller controls the plane of the filter plate 3 to be perpendicular to the direct sunlight rays, specifically referring to Figure 8; When the solar irradiation is too strong and the PPFD of the open space is much greater than the PPFD required by the crops, the first regulation mode is adopted, that is, the plane where the light filter plate 3 is located is adjusted to be perpendicular to the direct sunlight, so that the solar radiation incident on the device is minimized. In this mode, the device has the maximum degree of shielding of the incident light, effectively reducing the total irradiance under the device and preventing the plants from experiencing photoinhibition due to excessive light intensity.

[0074] In the first regulation mode, the rotation angle of the second shaft body 5 along the second preset direction is controlled to be A, the rotation angle of the first shaft body 4 along the first preset direction is controlled to be B, B = -sin -1 (sinθ * cosα); where α is the solar altitude angle and θ is the solar azimuth angle; the value range of A is (-90°, 0°), and the value range of B is (-90°, 90°).

[0075] Second regulation mode. When the solar irradiance is less than the second preset value and the external PPFD > internal PPFD, the microcontroller regulates the plane where the light filter plate 3 is located to be parallel to the direct sunlight, specifically referring to Figure 7 ; When the solar irradiation is very low and the PPFD of the open space is less than the PPFD required by the crops, the second regulation mode is adopted, that is, the plane where the light filter plate is located is adjusted to be parallel to the direct sunlight. At this time, the device has the minimum degree of shielding of the incident light, and the solar radiation incident on the device is the largest, ensuring that the PPFD under the device can still meet the growth requirements of the crops when the solar radiation is weak.

[0076] In the second regulation mode, the rotation angle of the first shaft body 4 along the first preset direction is controlled to be B, or the rotation angle of the second shaft body 5 along the second preset direction is controlled to be A,

[0077]

[0078] When in the second regulation mode, as long as the specific tracking angle satisfies the following formula, the plane where the light filter plate 3 is located is parallel to the direct sunlight;

[0079] sinA * cosB * cosθ * cosα + sinθ * cosα * sinB + cosA * cosB * sinα = 0.

[0080] Third regulation mode. According to the set target PPFD, measured PPFD and solar irradiance of the crops planted under the ceiling structure, the placement angle of the light filter plate 3 is adjusted to meet the set target PPFD for plant growth and minimize the spectral shift. This mode realizes the optimal matching of light intensity and spectrum by finely adjusting the angle of the light filter plate.

[0081] In a preferred embodiment of the present invention, the microcontroller includes:

[0082] A first calculation unit for calculating the shadow area S1 generated by occlusion according to the size, height of the light filter plate 3 in the ceiling structure, and the current rotation angles A and B of the light filter plate 3;

[0083] A parameter acquisition unit for acquiring the external PPFD and the internal PPFD;

[0084] A second calculation unit for calculating the rotation angles A and B that meet the target PPFD requirement according to the following formula: Pd = P1 * (S - S1) / S + P0 * S1 / S, where S is the total area of the light filter plate 3 array, Pd is the target PPFD, P1 is the external PPFD, and P0 is the internal PPFD;

[0085] A result output unit for selecting a set of results with the shortest adjustment step from the calculated multiple sets of rotation angles A and B for angle adjustment;

[0086] The angle adjustment includes the following steps:

[0087] Fine-tuning the light filter plate 3 according to the actually measured PPFD under the plate until the target PPFD is reached;

[0088] If the actual PPFD is less than the target PPFD, then reduce the angle between the normal direction of the light filter plate 3 and the direct sunlight;

[0089] If the actual PPFD is greater than the target PPFD, then increase the angle between the normal direction of the light filter plate 3 and the direct sunlight.

[0090] In a preferred embodiment of the present invention, in the first calculation unit, calculating the shadow area S1 generated by occlusion includes the following steps:

[0091] S100: Taking the center position of the light filter plate 3 as the origin 0, 0, 0, taking the first preset direction as the x-axis, taking the second preset direction as the y-axis, and taking the direction perpendicular to the ground and upward as the z-axis to establish a space rectangular coordinate system;

[0092] S200: Setting the length of the light filter plate 3 as a meters, the width as b meters, the installation height as c meters, and the coordinates of the four vertices of the light filter plate 3 as P1 = (0.5a, 0.5b, 0), P2 = (-0.5a, 0.5b, 0), P3 = (0.5a, -0.5b, 0), P4 = (-0.5a, -0.5b, 0);

[0093] S300: Combining the rotation angles A and B to calculate the coordinates P 1 ‘, P 2 ’, P 3 ‘, P 4 ';

[0094] S400. Calculate the projected coordinates P of the four vertices on the ground by combining the real-time solar altitude angle and solar azimuth angle. 1 ’‘, P 2 ’‘, P 3 ’‘, P 4 ’';

[0095] S500. In the coordinate region, the shaded area S1 = S shadow (P′ 1 ′, P′ 2 ′, P′ 3 ′, P′ 4 ′) ∩ S; S shadow where S refers to the rectangular shaded range composed of P′ 1 ′, P′ 2 ′, P′ 3 ′, P′ 4 ′.

[0096] More preferably, an optimization algorithm is used to select the rotation path with the least cumulative rotation angle, denoted as min(∑(|A| + |B|)). This method can be used for the rotation angle selection in the second control mode and the third control mode.

[0097] The specific steps are as follows:

[0098] 1. Input the geographical location and date to obtain the solar trajectory data.

[0099] 2. Set the angle change threshold to 1 degree, that is, the motor will operate only after the angle changes by 1 degree.

[0100] 3. Set the initial angle and calculate the daily rotation angle.

[0101] 4. Record the cumulative rotation angle ∑(|A| + |B|) for traversing one day.

[0102] 5. Use the optimization algorithm to find the best path of min(∑(|A| + |B|)).

[0103] In the above embodiments, the solar altitude angle α and the solar azimuth angle θ can be calculated by astronomical algorithm formulas, specifically including:

[0104] The local standard time meridian LSTM is calculated according to the following formula:

[0105] LSTM = 15°·ΔT UTC

[0106] ΔT UTC is the difference in hours between the local time (LT) and the Coordinated Universal Time (UTC).

[0107] Use the Equation of Time (EoT), an empirical equation, to correct for the effects of the eccentricity of the Earth's orbit and the tilt of the Earth's axis.

[0108] EoT = 9.87sin(2B) - 7.53cos(B) - 1.5sin(B)

[0109] Where:

[0110]

[0111] In the formula, yearDay refers to the total number of days in the current year, and d is the day of the year, which is the number of the current day in a year.

[0112] The net time correction factor TC is calculated according to the following formula:

[0113] TC = 4·(Longitude - LSTM) + EoT

[0114] Furthermore, the hour angle HRA and the solar declination angle δ of the current day are obtained:

[0115] HRA = 15°·(LST - 12)

[0116]

[0117] The solar altitude angle α can be obtained through the following formula:

[0118]

[0119] From this, the solar azimuth angle θ can be obtained:

[0120]

[0121] When HRA < 0:

[0122] θ = Azimuth

[0123] When HRA > 0:

[0124] θ = 360° - Azimuth

[0125] In a preferred embodiment of the present invention, a method for optical field regulation using the ceiling-mounted large-area optical field regulation device as described above is proposed, including the following steps:

[0126] S1. Use the solar irradiance sensor 2 to monitor the total irradiance at the location of the device, as a reference value for the light adjustment of the overall device;

[0127] S2. Use the PPFD sensor 1 to measure the external PPFD and the internal PPFD respectively;

[0128] S3. The microcontroller receives the data of PPFD and solar irradiance, and regulates the transmission device to change the angle of the light filter plate 3, adjust the incident amount and filtering amount of sunlight, and achieve one of the following three regulation modes:

[0129] In the first regulation mode, when the solar irradiance is greater than the first preset value and the external PPFD > the internal PPFD, the microcontroller regulates the plane where the light filter plate 3 is located to be perpendicular to the direct solar rays;

[0130] In the second regulation mode, when the solar irradiance is less than the second preset value and the external PPFD > the internal PPFD, the microcontroller regulates the plane where the light filter plate 3 is located to be parallel to the direct solar rays;

[0131] In the third regulation mode, according to the set target PPFD, the measured PPFD and the solar irradiance of the crops planted under the ceiling structure, the placement angle of the light filter plate 3 is adjusted to meet the set target PPFD for plant growth and minimize the spectral shift.

[0132] According to the above embodiments of the present invention, the above device and method meet the lighting requirements of different crops at different growth stages by precisely regulating the light intensity and spectral distribution. At the same time, the device effectively reduces the temperature and soil water evaporation amount under the device, providing a more suitable environment for crop growth. Specifically, under the climatic conditions of extreme high temperature and reduced precipitation, the device can ensure that the crops obtain sufficient light and a suitable growth environment, thereby avoiding the reduction in yield and quality caused by climate change. In addition, by optimizing the lighting conditions, the photosynthetic efficiency and yield of the crops are improved, bringing significant economic and social benefits to agricultural production.

[0133] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or by a combination of computer software and electronic hardware. Whether these functions are executed in hardware or software depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0134] In addition, in each embodiment of the present application, the various functional modules can be integrated in one processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit.

[0135] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present application.

Claims

1. A ceiling-mounted large-area light field control device, characterized in that: include: A ceiling structure, comprising an array-arranged filter plate (3) and a transmission device thereof, wherein a polymer multilayer optical film (31) is attached to the outer side of the filter plate (3), wherein the polymer multilayer optical film (31) is a multilayer film layer in which high-refractive index film layers and low-refractive index film layers are alternately stacked, and is used to select and transmit red light, blue light and far-red light from sunlight for plant growth below the ceiling structure; A PPFD sensor (1) and an irradiance sensor (2), used for monitoring PPFD and solar irradiance, respectively; The microcontroller is used for receiving the PPFD and the sunlight irradiance and regulating the transmission device to change the angle of the filter plate (3) and adjust the incident amount and filtered amount of sunlight.

2. A ceiling-mounted large-area light field control device according to claim 1, characterized in that: The ceiling structure also includes a mounting bracket (4), the transmission device includes a rotating motor (6) arranged at a horizontal axis above the mounting bracket (4), and includes a second shaft (5) and a corresponding rotating motor (7) arranged on the mounting bracket (4); the filter plate (3) is connected to the first shaft (4) and is used to rotate along a first preset direction under the drive of the rotating motor (6); the filter plate (3) is connected to the second shaft (5) and is used to rotate along a second preset direction under the drive of the rotating motor (7); The first preset direction is used to characterize the orientation angle of the filter plate (3), and the second preset direction is used to characterize the tilt angle of the filter plate (3).

3. A ceiling-mounted large-area light field control device according to claim 2, characterized in that: The transmission device comprises a pulley block (8) arranged on the transverse axis, and a transmission rope (9) arranged between the pulley block (8) and the rotating motor (6), wherein the transmission rope (9) passes through the middle section of the filter plate (3); The first rotating motor (6) is connected to the filter plate (3) via a transmission rope (9) and a pulley block (8), and the second rotating motor (7) is connected to the filter plate (3) via a shaft (5) to adjust the angle of the filter plate (3).

4. The large-area light field control device of a ceiling type according to claim 3, characterized in that: The PPFD sensors (1) are distributed outside the suspended ceiling structure and below the suspended ceiling structure to measure external PPFD and internal PPFD respectively; the irradiance sensors (2) are distributed outside the suspended ceiling structure to measure solar irradiance.

5. The large-area light field control device of a ceiling type according to claim 4, characterized in that: The microcontroller receives the PPFD and the solar irradiance and regulates the transmission device to implement a control mode of the filter plate (3) pre-configured by the system, wherein the control mode includes: In a first control mode, when the sunlight irradiance is greater than a first preset value and the external PPFD is greater than the internal PPFD, the microcontroller controls the plane where the filter plate (3) is located to be perpendicular to the direct sunlight; In the second control mode, when the solar irradiance is less than a second preset value and the external PPFD is greater than the internal PPFD, the microcontroller controls the plane where the filter plate (3) is located to be parallel to the direct sunlight; In the third control mode, the placement angle of the filter plate (3) is adjusted according to the set target PPFD of the crops planted under the ceiling structure, the measured PPFD and the solar irradiance, so as to meet the set target PPFD for plant growth and minimize the spectral shift.

6. The large-area light field control device of a ceiling type according to claim 5, characterized in that: In the first control mode, the second shaft (5) is controlled to rotate at an angle A along a second preset direction, Control the first shaft (4) to rotate along the first preset direction at an angle B, where B = -sin -1 (sinθ*cosα); where α is the solar altitude angle, θ is the solar azimuth angle; the value range of A is (-90°, 0°), and the value range of B is (-90°, 90°).

7. The ceiling-mounted large-area light field control device according to claim 6, characterized in that: In the second control mode, the first shaft (4) is controlled to rotate at an angle B along a first preset direction, or controlling the second shaft (5) to rotate along the second preset direction at an angle A, 8. The ceiling-mounted large-area light field control device according to claim 7, characterized in that: The microcontroller comprises: A first calculation unit is used to calculate a shadow area S1 generated by the occlusion according to the size and height of the filter plate (3) in the ceiling structure and the current rotation angles A and B of the filter plate (3); A parameter acquisition unit, used for acquiring the external PPFD and the internal PPFD; A second calculation unit is used to calculate the rotation angles A and B that meet the target PPFD requirements according to the following formula: Pd=P1*(S-S1) / S+P0*S1 / S, where S is the total area of ​​the filter plate (3) array, Pd is the target PPFD, P1 is the external PPFD, and P0 is the internal PPFD; A result output unit is used to select a group of results with the shortest adjustment step length from the multiple groups of rotation angles A and B obtained by calculation to adjust the angle; The angle adjustment comprises the following steps: According to the actually measured PPFD under the plate, the filter plate (3) is fine-tuned until the target PPFD is achieved; If the actual PPFD is less than the target PPFD, the angle between the normal direction of the filter plate (3) and the direct sunlight is reduced; If the actual PPFD is greater than the target PPFD, the angle between the normal direction of the filter plate (3) and the direct sunlight is increased.

9. The ceiling-mounted large-area light field control device according to claim 8, characterized in that: In the first calculation unit, calculating the shadow area S1 caused by the occlusion includes the following steps: A spatial rectangular coordinate system is established with the center position of the filter plate (3) as the origin (0, 0, 0), the first preset direction as the x-axis, the second preset direction as the y-axis, and the z-axis perpendicular to the ground and upwards as the z-axis; The length of the filter plate (3) is set to a meter, the width is set to b meter, the installation height is set to c meter, and the coordinates of the four vertices of the filter plate (3) are set to P1 = (0.5a, 0.5b, 0), P2 = (-0.5a, 0.5b, 0), P3 = (0.5a, -0.5b, 0), and P4 = (-0.5a, -0.5b, 0); Combined with the rotation angles A and B, calculate the coordinates of the four vertices after rotation, P1′, P2′, P3′, P4′; Combine the real-time solar altitude angle and solar azimuth angle to calculate the projection coordinates P1″, P2″, P3″, P4″ of the four vertices on the ground; In the coordinate area, the shaded area S1 = S shadow (P″1,P″2,P″3,P″4)∩S.

10. A method for light field control using the ceiling-mounted large-area light field control device according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1, using a solar irradiance sensor (2) to monitor the total irradiance at the location of the device as a reference value for light adjustment of the entire device; S2, using the PPFD sensor (1) to measure the external PPFD and the internal PPFD respectively; S3, the microcontroller receives the data of PPFD and solar irradiance and controls the transmission device to change the angle of the filter plate (3), adjust the incident amount and filtered amount of sunlight, and realize one of the following three control modes: In a first control mode, when the sunlight irradiance is greater than a first preset value and the external PPFD is greater than the internal PPFD, the microcontroller controls the plane where the filter plate (3) is located to be perpendicular to the direct sunlight; In the second control mode, when the solar irradiance is less than a second preset value and the external PPFD is greater than the internal PPFD, the microcontroller controls the plane where the filter plate (3) is located to be parallel to the direct sunlight; In the third control mode, the placement angle of the filter plate (3) is adjusted according to the set target PPFD of the crops planted under the ceiling structure, the measured PPFD and the solar irradiance, so as to meet the set target PPFD for plant growth and minimize the spectral shift.

Images