WO2022219597A1

WO2022219597A1 - Solar power generation system and method thereof

Info

Publication number: WO2022219597A1
Application number: PCT/IB2022/053558
Authority: WO
Inventors: Radhakrishnan S.K.; Savithiri R.
Original assignee: S K Radhakrishnan; R Savithiri
Priority date: 2021-04-16
Filing date: 2022-04-15
Publication date: 2022-10-20

Abstract

The present disclosure provides a solar power generation system. The solar power generation system includes a solar tracking cloud radar apparatus (100, 300) and at least one solar photovoltaic panel (214, 314) mounted on at least one two-axis rotating type frame that can be tilted on both the E-W and N-S axes. The solar tracking cloud radar apparatus (100, 300) comprises a frame member (101, 301) having a convex top surface (104, 110, 303); a first set of optical sensors (106, 306) disposed along a first direction (X-X') on the convex top surface (104, 110, 303) of the frame member (102, 108, 301); and a second set of optical sensors (112, 312) disposed along a second direction (Y-Y') on the convex top surface (110, 303) of the frame member (101, 301), the second direction being substantially perpendicular to the first direction. The solar tracking cloud radar apparatus not only detects the exact sun's position when the sun is not masked by a cloud or overcast but also detects the maximum light intensity spot in the sky, whenever the sun is masked by a cloud or overcast, and wherein the maximum light intensity spot in the sky may be away from the exact sun's position.

Description

SOLAR POWER GENERATION SYSTEM AND METHOD THEREOF

TECHNICAL FIELD

[0001 ] The present disclosure relates to the field of solar energy, and more particularly to solar tracking cloud radar apparatus, a solar power generation system and a method thereof.

BACKGROUND

[0002] Solar tracker is an apparatus constructed with necessary structural assembly arrangement with suitable drive sources to track sun’s position, at regular intervals, to orient surface of solar panel, normal to the sun’s light rays. There are two main types of solar trackers available in the market: single axis solar trackers and dual axis solar trackers. The single axis solar trackers are built to dynamically orient solar photovoltaic panels to cover only East-West motion of the sun, on a daily basis. Since the single axis solar trackers have the limited tracking potential, an additional power generation (productivity) by deploying single axis solar tracking is also limited. The approximate productivity of a single axis solar tracker is said to be in the order of 16% (yearly average) over an equivalent fixed tilt solar power plant, when mono-facial panels are used. Further, the dual axis solar trackers are designed to cover both the East-West and North-South motions of the sun simultaneously and hence the potential additional power generation (productivity) by deploying a dual axis solar tracker is said to be around 35% (yearly average) over an equivalent fixed tilt solar power plant, when mono-facial panels are used.

[0003] In both the single axis solar trackers and dual axis solar trackers, the solar panels are made to tilt towards the sun’s position at regular short intervals of time in order to orient the top surface of the solar panel is normal to the sun rays, to maximize the power generation.

[0004] Generally, the tilting of the solar panels mounted on the solar trackers is controlled by two types of control systems as given below.

[0005] (1) Open loop control system: The solar panels mounted on the solar trackers are made to tilt at predetermined angles at regular intervals of time to face the sun by a tracker controller which is guided by the open loop control system algorithm with respect to time and location. This open loop control system is mainly used to tilt the solar panels of any solar tracker during two back tracking periods in a day; in the morning and in the evening. The main purpose of the back tracking is to avoid falling of the shadow of one row on the next successive row both during sun rise and sun set periods.

[0006] (2) Closed loop control system: The solar panels mounted on the solar trackers are tilted to face the sun in order to maintain the top surface of the solar panels receive the sun rays vertically to generate maximum power. This tilting of the panels at regular intervals of time is guided by a light sensor or sensors mounted on the tracker or on the solar panel frame as the case may be. The light sensors are programmed to follow the full intensity of light directly coming from the sun. The closed loop system is mainly used to tilt the solar panels during the period between the closing time of the back tracking in the morning and the commencement of the back tracking in the evening.

[0007] Under the closed loop system, whenever the sky is clear i.e., without any cloud, the sun is bright and the light sensors follow the sun at regular intervals. But whenever the sun is masked by a cloud or whenever the sky is completely over cast, the full intensity of light coming directly from the sun will be absent. So, whenever the sensors miss the full intensity of light directly coming from the sun, the present solar trackers in the market are programmed to tilt the solar trackers to the stow position or horizontal position to the ground to optimize the power generation from the time the sun is masked by the cloud till such time the sun is back with full intensity light after the cloud get past the sun.

[0008] Tilting the trackers to the stow position or to the horizontal position, whenever the sun masked by the cloud, results in loss of power generation. Proportional to the frequency of the above-mentioned cloud phenomenon in a day, the power generation is reduced and this loss of power due to this cloud phenomenon is estimated to the tune of 10% on a yearly basis.

[0009] Thus, there remains a need to find a solution to reduce the loss of power generation due to the cloud phenomenon. Accordingly, a solar tracker is provided to determine maximum light intensity spot in the sky under cloudy or overcast conditions that maximizes solar power generation during the cloudy or overcast weather conditions.

SUMMARY

[0010] This summary is provided to introduce a selection of concepts in a simplified format that are further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention, and nor is it intended for determining the scope of the invention.

[0011 ] The present disclosure relates to a solar tracking cloud radar apparatus that has plurality of optical sensors at different angles on two curved structure arrangement corresponding to E-W and N-S tilting directions. The solar tracking cloud radar apparatus only detects the exact sun’s position when the sun is not masked by a cloud or overcast but also detects the maximum light intensity spot in the sky, whenever the sun is masked by a cloud or overcast, and wherein the maximum light intensity spot in the sky may be away from the exact sun’s position. Thus, the present disclosure assists in tilting of solar photovoltaic cell(s) of a “sun-tracking-type system” towards the exact sun’s position, when the sun is not masked by a cloud or overcast or towards the maximum light intensity spot in the sky, whenever the sun is masked by a cloud or overcast thus maximizes solar power generation during cloudy weather.

[0012] To further clarify advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

BRIEF DESCRIPTION OF THE FIGURES

[0013] In order that the invention may be readily understood and put into practical effect, reference will now be made to exemplary embodiments as illustrated with reference to the accompanying drawings, where like reference numerals refer to identical or functionally similar elements throughout the separate views. The figures together with a detailed description below, are incorporated in and form part of the specification, and serve to further illustrate the embodiments and explain various principles and advantages, in accordance with the present invention where:

[0014] Figure 1 illustrates a perspective view of a solar tracking cloud radar apparatus constructed in accordance with an embodiment of the present disclosure;

[0015] Figure 2 illustrates a perspective view of a two-axis rotatable frame constructed in accordance with an embodiment of the present disclosure;

[0016] Figure 3 depicts a perspective view of a solar tracking cloud radar apparatus constructed in accordance with an embodiment of the present disclosure;

[0017] Figure 4 depicts a top view of the solar tracking cloud radar apparatus constructed in accordance with an embodiment of the present disclosure;

[0018] Figure 5 and Figure 6 illustrate angle of tilting of optical sensors in accordance with an embodiment of the present disclosure.

[0019] Figure 7, Figure 8 and Figure 9 depict a solar power generation system in accordance with an embodiment of the present disclosure.

[0020] It may be noted that to the extent possible, like reference numerals have been used to represent like elements in the drawings. Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have been necessarily been drawn to scale. For example, the dimensions of some of the elements in the drawings may be exaggerated relative to other elements to help to improve understanding of aspects of the present invention. Furthermore, the one or more elements may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

DETAIFED DESCRIPTION

[0021 ] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the invention and are not intended to be restrictive thereof.

[0022] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.

[0023] Reference throughout this specification to “an aspect”, “another aspect” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrase “in an embodiment”, “in another embodiment” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

[0024] The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or sub-systems or elements or structures or components proceeded by "comprises... a" does not, without more constraints, preclude the existence of other devices or other sub systems or other elements or other structures or other components or additional devices or additional sub systems or additional elements or additional structures or additional components.

[0025] As used herein, and unless the context dictates otherwise, the terms "coupled to", “connected to”, “operably connected to”, “operatively connected to” are intended to include both direct connection / coupling (in which two elements that are coupled / connected to each other contact each other) and indirect coupling / connection (in which at least one additional element is located between the two elements). Therefore, the terms "coupled to" and "coupled with" are used synonymously. Similarly, the terms “connected to” and “connected with” are used synonymously.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skilled in the art to which this invention belongs. The device, methods, and examples provided herein are illustrative only and not intended to be limiting. Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims. Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

[0027] The present disclosure provides a solar tracking cloud radar apparatus or solar tracker or a cloud radar system designed to have a plurality of optical sensors at different angles on two curved structure arrangement corresponding to a plurality of tilting directions to discover the brightest spot in the sky, whenever the sun is masked by the passing cloud or over cast. That is, the present disclosure does only not detect the exact sun’s position when the sun is not masked by a cloud or overcast but also detects the maximum light intensity spot in the sky, whenever the sun is masked by the cloud or overcast, and wherein the maximum light intensity spot in the sky may be away from the exact sun’s position. Thus, the “solar tracking cloud radar apparatus” assists in tilting of solar photovoltaic cell(s) of a “solar power generation system” towards the exact sun’s position, when the sun is not masked by a cloud or overcast or towards the maximum light intensity spot in the sky, whenever the sun is masked by a cloud or overcast. Thus, the solar power generation system receives the maximum intensity of sun rays.

[0028] The solar power generation system having the solar tracking cloud radar apparatus has a unique globe design with light intensity detecting sensors radially fitted at fixed angle intervals in both E-W (east-west) and N-S (north-south) directions, to locate the sun’s position in the sky or alternatively to locate the next best brightest spot in the sky whenever the sun is masked by cloud, by determining the angles of location in both XX and YY axes using artificial intelligence from time to time corresponding to the Lat long of the location of the solar plant and to direct the solar tracker controller to navigate the tilting of solar panels in such a way that either direct light rays from the sun or alternatively from the reflected sun ray from the next brightest spot in the sky whenever the sun is masked by the cloud falls vertically on the solar panel surface, to maximize the solar power generation at any point of time.

[0029] The present disclosure provides the solar tracking cloud radar apparatus to navigate the tilting of solar panels in such a way that either direct light rays from the sun or alternatively from the reflected sun ray from the next brightest spot in the sky whenever the sun is masked by the cloud or overcast falls vertically on the solar panel surface, to maximize the solar power generation.

[0030] The solar tracking cloud radar apparatus (solar tracker) designed to determine maximum light intensity spot in the sky under cloudy or overcast conditions, thereby maximizing solar power generation during the cloudy or overcast weather conditions. Advantageously, the loss of power due to the cloud phenomenon can be reduced up to 4%. In other words, by using this present disclosure, every solar power generation system can generate 6% additional power. The terms brightest spot and maximum light intensity spot, maximum intensity spot have been used interchangeably throughout the specification. [0031 ] Followings are the features of the present disclosure: • A solar tracking cloud radar apparatus (100, 300), comprising: a frame member (101, 301) having a convex top surface (104, 110, 303); a first set of optical sensors (106, 306) disposed along a first direction (X-X’) on the convex top surface (104, 110, 303) of the frame member (102, 108, 301); and a second set of optical sensors (112, 312) disposed along a second direction (Y-Y’) on the convex top surface (110, 303) of the frame member (101, 301), the second direction being substantially perpendicular to the first direction, said first set of optical sensors (106, 306) and second set of optical sensors (112, 312) being disposed radially at fixed angle intervals on the convex top surface (110, 303) to provide coordinate angle of location in X-X’ and Y-Y’ axes respectively of a maximum light intensity spot in the sky whenever sun is masked by a cloud or overcast.

• The first set of optical sensors (106, 306) include a plurality of optical sensors which is spaced apart from one another by an angle Q1 and the second set of optical sensors (112, 312) include the plurality of optical sensors which is spaced apart from one another by angle Q1, the value of Q1 being in the range of 70° to 130°.

• The first set of optical sensors (306) disposed along a first direction (X-X’) is based on an angle of tilting in E-W direction (02); and the second set of optical sensors (312) disposed along a second direction (Y-Y’) is based on an angle of tilting in N-S direction (03).

• The frame member (301) is in the form of a dome-shaped structure.

• The frame member (101, 301) comprises: a first frame member (102, 302) having a convex top surface (104, 304) and a second frame member (108, 308) having a convex top surface (310), the second frame member (108, 308) being located substantially perpendicular to the first frame member (102, 302) during operation.

• The first set of optical sensors (106, 306) is disposed on the convex top surface (104, 304) of the first frame member (102, 302); and the second set of optical sensors (112, 312) is disposed on the convex top surface (110, 310) of the second frame member (108, 308).

• The first frame member (102) and the second frame member (108) are not physically connected with other.

• The first frame member (102) and the second frame member (108) are physically connected with other such that the first frame member (102) and the second frame member (108) intersect each other at an intersection point at right angle and the first frame member (102) and the second frame member (108) dissect each other at the intersection point.

• The solar tracking cloud radar apparatus (100, 300) comprises a common optical sensor (120) located at the intersection point such that a Z-Z axis passes through the common optical sensor (320), wherein the common optical sensor (320) primarily tracks exact position of the sun while the first set of optical sensors (306) and the second set of optical sensors (312) detect the maximum light intensity spot in the sky, whenever the sun is masked by a cloud.

• The location of the first set of optical sensors (106) is not overlapping with the location of the common optical sensor and the location of the second set of optical sensors (112) is not overlapping with the location of the common optical sensor.

• The solar tracking cloud radar apparatus (100, 300) comprises a base frame (122) to which the first frame member (102) and the second frame member (108) are connected via connecting members (124).

• The solar tracking cloud radar apparatus is mounted on a non-rotating type frame.

• The solar tracking cloud radar apparatus (100) is mounted on a two-axis rotating type frame (116) constructed on the principle of horizontal primary dual axis tracker (HPDAT), the two-axis rotating type frame (116) comprises: a main frame (226) comprising an E-W arm (232) defining an E-W fulcrum (234) and an N-S arm (236) defining an N-S fulcrum (238); a C-channel assembly (228) integrated with the N-S fulcrum (236) of the main frame (226); pillar(s) (230) for supporting the main frame (226); an E-W drive system (240) for rotating the main frame (226) about the E-W fulcrum (234); and an N-S drive system (258) for rotating the C-channel assembly (228) at about the N-S fulcrum (236).

• A solar power generation system comprising: a solar tracking cloud radar apparatus (100, 300); and at least one solar photovoltaic panel (214, 314) mounted on at least one two-axis rotating type frame that can be tilted on both the E-W and N-S axes; the solar tracking cloud radar apparatus (100, 300) comprising: a frame member (101, 301) having a convex top surface (104, 110, 303); a first set of optical sensors (106, 306) disposed along a first direction (X-X’) on the convex top surface (104, 110, 303) of the frame member (102, 108, 301); a second set of optical sensors (112, 312) disposed along a second direction (Y-Y’) on the convex top surface (110, 303) of the frame member (101, 301), the second direction being substantially perpendicular to the first direction, said first set of optical sensors (106, 306) and second set of optical sensors (112, 312) being disposed radially at fixed angle intervals on the convex top surface (110, 303) to provide a coordinate angle of location in X-X’ and Y-Y’ axes respectively of a maximum light intensity spot in the sky whenever sun is masked by a cloud or overcast; a first controller (376i), connected to the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312), configured to determine the coordinate angle of location in X-X’ and Y-Y’ axes of at least one optical sensor from the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312) respectively of a maximum light intensity spot in the sky when sun is masked by the cloud or overcast; and at least one further controller (376₂) configured to receive the coordinate angle from the first controller (376i) to tilt the at least one solar photovoltaic panel (214, 314) based on the coordinate angle to generate maximum power.

• The solar tracking cloud radar apparatus is mounted on a two-axis rotating type frame (116, 316) constructed on the principle of horizontal primary dual axis tracker (HPDAT), the solar tracking cloud radar apparatus comprises a common optical sensor (120, 307).

• The solar power generation system comprising a first controller (376i) which connected to the first set of optical sensors (106, 306), the second set of optical sensors (112, 312) and the common optical sensor (120, 307), the first controller (376i) being adapted to: receive the inputs from the first set of optical sensors (106, 306), the second set of optical sensors (112, 312) and the common optical sensor (120, 307); tilt the two-axis rotating type frame (316) in accordance with the Open Loop Control System method; determine the exact position of the sun when the sun is not masked by a cloud or overcast; determine the maximum light intensity spot in the sky when the sun is masked by a cloud or overcast, wherein the maximum light intensity spot in the sky may be away from the exact sun’s position; and generate control signals on the basis of determination of the maximum light intensity spot to tilt the at least one solar photovoltaic panel (214, 314).

• The solar power generation system comprising at least one further controller (376₂) provided in operational relation with the at least one further two-axis rotating type frame (316), the at least one further controller (376₂) being in operational interconnection with the first controller (376i) for receiving therefrom the control signals, the at least one further controller (376₂) being configured to control the operation of a corresponding E-W drive system and corresponding N-S drive system based on the control signals received from the first controller (376i).

• The solar power generation system comprising a first controller (376i) which connected to the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312), the first controller (376_j) being adapted to: receive the inputs from the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312); determine the maximum light intensity spot in the sky when the sun is masked by a cloud or overcast, wherein the maximum light intensity spot in the sky may be away from the exact sun’s position; and generate control signals on the basis of the aforesaid detection.

• The first controller (376i) is in operational relation with an E-W drive system and an N-S drive system disposed in the two-axis rotating type frame (316).

• A method implemented by a solar generation system comprising: receiving by a first controller (376i) inputs from the first set of optical sensors (106, 306), the second set of optical sensors (112, 312) and the common optical sensor (120, 307); tilting the two-axis rotating type frame (116, 316) in accordance with the Open Loop Control System method; determining, by the first controller (376i), the exact position of the sun when the sun is not masked by a cloud or overcast; determining, by the first controller (376_j), the maximum light intensity spot in the sky when the sun is masked by a cloud or overcast, wherein the maximum light intensity spot in the sky may be away from the exact sun’s position; generating, by the first controller (376i), control signals on the basis of the aforesaid detection; transmitting, by the first controller (376i), the control signals to the at least one further controller (376₂); and controlling, by the at least one further controller (376₂), operation of a corresponding E-W drive system and corresponding N-S drive system based on the control signals received from the first controller (376i).

• A method implemented by a solar generation system comprising: receiving by a first controller (376i), inputs from a first set of optical sensors (106, 306) and a second set of optical sensors (112, 312); determining the maximum light intensity spot in the sky when the sun is masked by a cloud or overcast, wherein the maximum light intensity spot in the sky may be away from the exact sun’s position; generating control signals on the basis of the aforesaid detection; and controlling, by the first controller (376i), operation of an E-W drive system and an N-S drive system disposed in the two-axis rotating type frame (316) based on the control signals.

• The first controller (376i) is configured to compare light intensity received from the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312) to determine the coordinate angle of the at least one optical sensor from the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312) with the brightest spot when the sun is masked by the cloud or overcast. • The at least one further controller (370₂) configured to receive the coordinate angle from the first controller (376i) via an interface (402).

[0032] The solar tracking cloud radar apparatus (100) comprises a first frame member (102) having a convex top surface (104), a first set of optical sensors (106) disposed on the convex top surface (104) of the first frame member (102), a second frame member (108) having a convex top surface (110), the second frame member (108) being located substantially perpendicular to the first frame member (102) during operation, and a second set of optical sensors (112) disposed on the convex top surface (110) of the second frame member (108).

[0033] In an embodiment of the present disclosure, the first frame member (102) and the second frame member (108) are not physically connected with each other.

[0034] In another embodiment of the present disclosure, the first frame member (102) and the second frame member (108) are physically connected with each other such that the first frame member (102) and the second frame member (108) intersect each other at an intersection point at right angle and the first frame member (102) and the second frame member (108) dissect each other at the intersection point. [0035] In yet another embodiment of the present disclosure, the solar tracking cloud radar apparatus comprises a common optical sensor (120) located at the intersection point such that a Z-Z axis passes through the common optical sensor.

[0036] In still another embodiment of the present disclosure, the common optical sensor (120) primarily tracks the exact position of the sun while the first set of optical sensors (106) and the second set of optical sensors (112) detect the maximum light intensity spot in the sky, whenever the sun is masked by a cloud or overcast.

[0037] In a further embodiment of the present disclosure, the location of the first set of optical sensors (106) is not overlapping with the location of the common optical sensor and the location of the second set of optical sensors (112) is not overlapping with the location of the common optical sensor.

[0038] In a furthermore embodiment of the present disclosure, the first set of optical sensors (106) includes a plurality of optical sensors that is spaced apart from one another by angle Q1 and the second set of optical sensors (112) includes the plurality of optical sensors that is spaced apart from one another by angle Q1, the value of Q1 being in the range of 70° to 130° EW and NS. Preferably, the value of Q1 may be 110°EW and 72° NS.

[0039] In yet another embodiment of the present disclosure, a number of optical sensors mounted on the first frame member (102) is based on an angle of tilting in E-W direction (Q2) and a number of optical sensors mounted on the second frame member (308) is based on an angle of tilting in N-S direction (Q3). The value of Q2 may be in range of 45 to 65 degrees in the E-W direction and the value of Q3 may be in range of 28 to 46 degrees in the N-S direction. [0040] In still another embodiment of the present disclosure, the solar tracking cloud radar apparatus (100) comprises a base frame (122) to which the first frame member (102) and the second frame member (108) are connected via connecting members (124).

[0041 ] In a further embodiment of the present disclosure, the solar tracking cloud radar apparatus (100) is mounted on a two-axis rotating type frame (216) constructed on the principle of horizontal primary dual axis tracker (HPDAT), the two-axis rotating type frame (216) comprises: a main frame (226) comprising an E-W arm (232) defining an E-W fulcrum (234) and an N-S arm (236) defining an N-S fulcrum (238); a C-channel assembly (228) integrated with the N-S fulcrum (236) of the main frame (226); pillar(s) (230) for supporting the main frame (226); an E-W drive system (240) for rotating the main frame (226) about the E-W fulcrum (234); and an N-S drive system (258) for rotating the C-channel assembly (228) at about the N-S fulcrum (236).

[0042] The E-W drive system (240) consists of a worm shaft module arrangement, which is integrated with the pillar (230). A worm shaft assembled inside the worm shaft module arrangement, is driven by a worm shaft drive gear box powered by an E-W DC stepper motor. There is a worm gear segment guided by the worm gear segment guide rollers and fixed with the worm gear segment link brackets which tilts the E-W arm (232) in the E-W direction. Akin to worm gear segment guide rollers, worm gear segment rain pads are provided on both sides of the worm shaft module arrangement.

[0043] The N-S drive system (258) consists of a Linear movement screw box fitted with a N-S drive system gear box driving the Linear movement screw box to result a forward and reverse linear motion to the Linear movement screw box shaft. The N-S drive system (258) is powered by a N-S drive system DC stepper motor fitted with the N-S drive system gear box. The Linear motion screw box shaft is connected to a Linear movement push rod which in turn is connected to a piston assembly to result a forward and reverse movement to a piston lever shaft. The piston lever shaft is engaged and made to slide with a C- channel assembly tilting lever for tilting the C-channel assembly about the Y-Y- axis passing through the N-S fulcrum in the N-S direction.

[0044] The two-axis rotating type frame (216) as described above can also be used for mounting of at least one solar photovoltaic panel (214).

[0045] The solar tracking cloud radar apparatus (100) mounted on the two-axis rotating type frame (216) can be tilted on both the E-W and N-S axes. The titling is controlled in accordance with the Open Loop Control System method. As per the Open Loop Control System method, the two-axis rotating type frame (216) is tilted such that the solar tracking cloud radar apparatus (100) tracks the exact position of the sun in such a way that the sun ray is perpendicular to the common optical sensor (Common Light Dependent Resistor (CLDR) sensor) and coincides with the Z-Z- axis and matching the position of the CLDR sensor. [0046] The solar power generation system comprises the solar tracking cloud radar apparatus (100) mounted on the two-axis rotating type frame (216) that can be tilted on both the E-W and N-S axes and at least one solar photovoltaic panel (214) mounted on at least one further two-axis rotating type frame that can be tilted on both the E-W and N-S axes.

[0047] It is believed that the solar power generation system incorporating the solar tracking cloud radar apparatus (100) having the construction as mentioned above not only detects with high accuracy the exact sun’s position (when the sun is not masked by a cloud or overcast) but also detects with high accuracy the maximum light intensity spot in the sky (when the sun is masked and which) and hence, the present disclosure addresses the disadvantages in the conventional solar trackers as discussed earlier.

[0048] Figure 3 depicts a perspective view of the solar tracking cloud radar apparatus constructed in accordance with an embodiment of the present disclosure. Figure 4 depicts a top view of the solar tracking cloud radar apparatus constructed in accordance with an embodiment of the present disclosure. Figure 5 and Figure 6 illustrate angle of tilting of optical sensors in accordance with an embodiment of the present disclosure.

[0049] The solar tracking cloud radar apparatus (300) comprises a frame member (301) having a convex top surface (303), a first set of optical sensors (306) disposed along a first direction (X-X’) on the convex top surface (303) of the frame member (301) and a second set of optical sensors (312) disposed along a second direction (Y-Y’) on the convex top surface (303) of the frame member (301). The second direction may substantially be perpendicular to the first direction. The frame member (301) may be a non rotating type frame member.

[0050] The solar tracking cloud radar apparatus (300) has a unique globe design with a plurality of optical sensors radially fitted on four radial dishes. The plurality of optical sensors may be, but not limited to, light dependent resistor (LDR) sensors. The plurality of optical sensors in the first set of optical sensors (306) is placed on radial dishes for E-W direction in the X-X axis direction and the plurality of optical sensors in the second set of optical sensors (312) is placed on radial dishes for N-S direction in the Y-Y axis direction. All the four radial dishes are assembled 90 degrees apart. The assembly is in such way that the Z-Z axis passes through one common optical sensor (307). The first set of optical sensors (306) on the frame member (301) for E-W direction is mounted with the plurality of optical sensors with angle Q2 as the angle between each optical sensor and Q1 as a spread angle of the plurality of optical sensors fitted. Similarly, the second set of optical sensors (312) holding the frame member (301) for N-S direction is mounted with the plurality of optical sensors with angle Q3 as the angle between each optical sensor and q 1 as the spread angle of the plurality of optical sensors fitted. In other words, the first set of optical sensors (306) disposed along a first direction (X-X’) is based on an angle of tilting in E-W direction (Q2) and the second set of optical sensors (312) disposed along a second direction (Y-Y’) is based on an angle of tilting in N-S direction (Q3). The value of Q1 being in the range of 70° to 130° EW and NS. Preferably, the value of Q1 may be 110° EW and 12 NS. The value of Q2 may be in range of 45 to 65 degrees in the E-W direction and the value of Q3 may be in range of 28 to 46 degrees in the N-S direction.

[0051 ] The plurality of optical sensors fitted radially on the frame member (301) having the convex top surface (303) along the X-X axis is set to cover the E-W direction and the plurality of optical sensors fitted radially on the frame member (301) having the convex top surface (303) along the Y-Y axis is set to cover the N-S direction of the location (Lat long) where the solar project (solar panel) is installed. The frame member (301) having the convex top surface (303) forms a dome-shaped structure in a preferred implementation.

[0052] Figure 7 and Figure 8 depict the solar power generation system in accordance with an embodiment of the present disclosure. The solar power generation system comprises a solar tracking cloud radar apparatus (100, 300), the at least one solar photovoltaic panel (214, 314) mounted on at least one two-axis rotating type frame (216, 316) that can be tilted on both the E-W and N-S axes. The solar tracking cloud radar apparatus (100, 300) comprises a frame member (301) having a convex top surface (104, 110, 303), the first set of optical sensors (106, 306) disposed along a first direction (x-x’) on the convex top surface (104, 303) of the frame member (102, 301) and the second set of optical sensors (112, 312) disposed along a second direction (y-y’) on the convex top surface (110, 303) of the frame member (108, 301). The second direction is substantially perpendicular to the first direction.

[0053] The solar tracking cloud radar apparatus (100, 300) not only detects the exact sun’s position when the sun is not masked by a cloud or overcast but also detects the maximum light intensity spot in the sky, whenever the sun is masked by a cloud or overcast, and wherein the maximum light intensity spot in the sky may be away from the exact sun’s position. Thus, the solar tracking cloud radar apparatus (100, 300) assists in tilting of solar photovoltaic cell(s) of a “closed loop control based sun-tracking-type system” towards the exact sun’s position, when the sun is not masked by a cloud or overcast or towards the maximum light intensity spot in the sky, whenever the sun is masked by a cloud or overcast. Thus, the solar tracking cloud radar apparatus (100, 300) allows for the solar photovoltaic cell(s) to receive the maximum intensity sun rays.

[0054] Referring to Figure 7, whenever the sun (9) is clear and the sky is without any cloud, all the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312) that are radially fitted sensors mounted along the direction of X-X axis (E-W) and Y-Y axis (N-S) receive the light intensity from the sun (9) and send it to a first controller (376_j) (as shown in Figure 9). The first controller (3760 compares the light intensity received by all the sensors and choses one optical sensor from each of the plurality of the optical sensors mounted in X-X and Y-Y direction with highest light intensity. Since all the optical sensors are mounted at predetermined angles on the radial dishes with respect to the X-X and Y-Y axes, the location of the sun is determined with its coordinate angles. This data is next sent to an interface (402) for further processing and the interface (402) directs the second controller (370₂) for the at least one solar photovoltaic panel (214, 314) mounted on at least one two- axis rotating type frame (216, 316) corresponding to the X-X and Y-Y angles chosen with the highest intensity of light by the solar tracking cloud radar apparatus (100, 300) to receive the light ray vertically to generate maximum power.

[0055] Referring to Figure 8, when the cloud (12) obstructs the direct sun light (13) to fall on the solar power generation system having the solar tracking cloud radar apparatus (100, 300), the solar tracking cloud radar apparatus (100, 300) does not receive any direct sun light from the sun (9). But when the direct sun light (19) falls on the nearby cloud (11) at spot (24), the reflected light from the spot (24) is received by the first set of optical sensors (106, 306) fitted in the XX axis direction (16) and the second set of optical sensors (112, 312) fitted in the YY axis direction (10). Now, the first controller (3760 with the support of the in-built artificial intelligence, compares the light intensity received by all the optical sensors and identifies the optical sensor (25) among the second set of optical sensors (112, 312) in the YY axis direction by receiving the cloud reflected light ray (14) and identifies the optical sensor (26) among all the first set of optical sensors (106, 306) in the XX axis direction by receiving the cloud reflected light ray (15). Since all the sensors are placed at fixed angle intervals ‘radially’ on the periphery of the globe of the solar tracking cloud radar apparatus (100, 300), the coordinate angle of location of the next brightest spot (24) is determined according to the angular location of the optical sensors (25, 26) in X-X’ and Y-Y’ axes respectively.

[0056] The determined coordinate angle(s) is processed by the interface (402) and the interface (402) directs the second controller (376₂) for the solar tracker to tilt in such a way that the cloud reflected light ray (20) from the next brightest spot (24) is received vertically to generate maximum power. The terms brightest spot and maximum intensity spot have been used interchangeably throughout the specification. [0057] The solar tracking cloud radar apparatus (100, 300) is installed along with every solar power project linked through the first controller (376i), the interface (402) and the second controller (376₂) as shown in Figure 9. The interface (402) may be HMI (Human Machine Interface). The first controller (376i), the interface (402) and the second controller (376₂) control the tilting of the solar panels mounted on the trackers corresponding to the sun’s dynamic location from time to time and Lat long. Whenever the closed loop system is taking command of the tracker control system to tilt the solar panels between the closing time of the back tracking in the morning and the commencement of the back tracking in the evening, the cloud radar system works as follows.

[0058] The above process is repeated at set fixed intervals of time in a day and correspondingly the solar panels are oriented in such a way that the surface of the solar panel is normal to receive the light ray either directly from the sun or to receive the light ray from the next brightest spot in the sky whenever sun is masked by cloud.

[0059] Referring to the Figures, by way of a first limiting example, the solar tracking cloud radar apparatus (100, 300) may be mounted on the at least one solar photovoltaic panel (214, 314). This aspect of the present disclosure is shown in Figures 1 and 2 wherein it can be seen that the first frame member (102) is mounted along a first side of the at least one solar photovoltaic cell while the second frame member (108) is mounted along a second side of the at least one solar photovoltaic cell, wherein the first side of the solar photovoltaic cell is perpendicular to the second side of the solar photovoltaic cell. Thus, in operation, the first frame member (102) and the second frame member (108) are located so as to be substantially perpendicular to one another.

[0060] As described above, the solar tracking cloud radar apparatus (100, 300) comprises the first frame member (102) having the first set of optical sensors (106) and the second frame member (108) having the second set of optical sensors (112). There is also provided the common optical sensor (120). There is further provided the first controller (376i) which connected to the first set of optical sensors, the second set of optical sensors and the common optical sensor (320). The first controller (376i) receives the inputs from the first set of optical sensors, the second set of optical sensors and the common optical sensor. The first controller (376i) tilts the two-axis rotating type frame on which the solar tracking cloud radar apparatus (100, 300) is mounted in accordance with the Open Loop Control System method (as described above). More particularly, the first controller (376i) provides signals to the E-W drive system and the N-S drive system that forms part of the two-axis rotating type frame so as to tilt the solar tracking cloud radar apparatus (100, 300) in accordance with the Open Loop Control System method.

[0061 ] The at least one further two-axis rotating type frame (not shown) comprises a corresponding E- W drive system and the N-S drive system. The at least one further two-axis rotating type frame further comprises at least one further controller. The at least one further controller is in operational interconnection with the first controller (376i). The first controller (376i) and the further controller may include least one or more processors, micro controllers, microprocessors and utilize artificial intelligence or machine learning techniques. The first controller (376i) determines the exact position of the sun when the sun is not masked by a cloud or overcast (on the basis of the output from the common optical sensor). In case the sun is masked by a cloud or overcast, the first controller (376i) determines the maximum light intensity spot in the sky, wherein the maximum light intensity spot in the sky may be away from the exact sun’s position. Thus, the first controller (376i) generates control signals on the basis of the aforesaid detection. The first controller (376i) is configured to send the control signals to the at least one further controller (second controller) (376₂). The second controller (376₂) then controls the operation of the corresponding E-W drive system and the N-S drive system based on the control signals received from the first controller (376i). Thus, the at least one further two-axis rotating type frame carrying the solar photo voltaic cell is operated in a Closed Loop Control System method on the basis of the control signals being provided by the first controller (376i).

[0062] A two-axis rotating type frame carrying the solar photovoltaic panel (214, 314) and the two- axis rotating type frame (116, 316) carrying the solar tracking cloud radar apparatus (100, 300) are installed at a site and the two-axis rotating type frame carrying the solar photovoltaic panel is made to operate on the basis of the output from the solar tracking cloud radar apparatus (100, 300) (which is mounted on the two-axis rotating type frame (116, 316)). Thus, the second controller (376₂) of the two- axis rotating type frame carrying the solar photovoltaic panel (214, 314) is integrated with the first controller (376i) of the two-axis rotating type frame carrying the solar tracking cloud radar apparatus (100, 300). Then both the two-axis rotating type frame (316) are made to track the sun’s dynamic position guided by the same Open Loop Control System method.

[0063] When the sky is clear and without any cloud or overcast, both the solar panel (214, 314) and the solar tracking cloud radar apparatus (100, 300) are dynamically oriented to face the sun’s ray in such a way that the Common Light dependent resistor (CLDR) sensor (120, 307) receives the sun’s ray vertically.

[0064] On the other hand, when there are clouds in the sky, the direct sun’s ray is masked by the cloud. In such a situation, any of the reflected sun’s ray may be brighter than direct sun’s ray. At this point, one of the first set of optical sensors mounted on the convex top surface of the first frame member and one of the second set of optical sensors mounted on the convex top surface of the first frame member discover these reflected sun’s rays.

[0065] On the basis of discovering these reflected sun’s rays, the control system can discover the next brightest spot in the sky (when the sun is masked by cloud(s)). The discovery of the next brightest spot in the sky when the sun is masked by a cloud can be based on a comparison of the output provided by each of the optical sensor forming part of the first set of optical sensors and the second set of optical sensors. Once the next brightest spot in the sky (when the sun is masked by cloud(s)) has been discovered, the two-axis rotating type frame carrying the at least one solar photovoltaic panel is made to rotate on the basis of the co-ordinates of the next brightest spot in the sky. Thus, the output of the solar tracking cloud radar apparatus (100, 300) ‘navigates’ the two-axis rotating type frame carrying the at least one solar photovoltaic panel so as to reorient its solar photovoltaic panel to face vertically the next brightest spot in the sky through the sun ray. This process is repeated for every interval of time so as to maximize the solar power generation during the cloudy or overcast weather.

[0066] It may be noted that by locating the first set of optical sensors disposed on the convex top surface of the first frame member, it is ensured that each one of the first set of optical sensors receives reflected sun’s ray which is perpendicular to its surface. Likewise, by locating the second set of optical sensors disposed on the convex top surface of the second frame member, it is ensured that each one of the second set of optical sensors receives reflected sun’s ray which is perpendicular to its surface. In case, the first set of optical sensors or the second set of optical sensors is located on a plane surface (as opposed to a convex surface), this feature of the present disclosure cannot be attained and hence, the accuracy of detecting the next brightest spot in the sky is less.

[0067] The solar tracking cloud radar apparatus (100, 300) can assist in tilting of solar photovoltaic cell(s) of a “closed loop control based sun-tracking-type system” so as to generate 4% to 6% more power than an equivalent “fixed tilt type system”, whenever the sun is masked by cloud or overcast.

[0068] The figures and the forgoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. Moreover, all elements shown in the diagrams need not be implemented. The scope of embodiments is by no means limited by these specific examples. Numerous variations, whether explicitly given in the specification or not, such as differences in structure, dimension, and use of material, are possible. The scope of embodiments is at least as broad as given by the following claims.

Claims

We Claim:

1. A solar tracking cloud radar apparatus (100, 300), comprising: a frame member (101, 301) having a convex top surface (104, 110, 303); a first set of optical sensors (106, 306) disposed along a first direction (X-X’) on the convex top surface (104, 110, 303) of the frame member (102, 108, 301); and a second set of optical sensors (112, 312) disposed along a second direction (Y-Y’) on the convex top surface (110, 303) of the frame member (101, 301), the second direction being substantially perpendicular to the first direction, said first set of optical sensors (106, 306) and second set of optical sensors (112, 312) being disposed radially at fixed angle intervals on the convex top surface (110, 303) to provide coordinate angle of location in X-X’ and Y-Y’ axes respectively of a maximum light intensity spot in the sky whenever sun is masked by a cloud or overcast.

2. The solar tracking cloud radar apparatus (100, 300) as claimed in claim 1, wherein the first set of optical sensors (106, 306) include a plurality of optical sensors which is spaced apart from one another by an angle Q1 and the second set of optical sensors (112, 312) include the plurality of optical sensors which is spaced apart from one another by angle Q1, the value of Q1 being in the range of 70° to 130°.

3. The solar tracking cloud radar apparatus (100, 300) as claimed in claim 1, wherein: the first set of optical sensors (306) disposed along a first direction (X-X’) is based on an angle of tilting in E-W direction (02); and the second set of optical sensors (312) disposed along a second direction (Y-Y’) is based on an angle of tilting in N-S direction (03).

4. The solar tracking cloud radar apparatus (100, 300) as claimed in claim 1, wherein the frame member (301) is in the form of a dome-shaped structure.

5. The solar tracking cloud radar apparatus (100, 300) as claimed in Claim 1, wherein the frame member (101, 301) comprises: a first frame member (102, 302) having a convex top surface (104, 304) and a second frame member (108, 308) having a convex top surface (310), the second frame member (108, 308) being located substantially perpendicular to the first frame member (102, 302) during operation, wherein the first set of optical sensors (106, 306) is disposed on the convex top surface (104, 304) of the first frame member (102, 302); and the second set of optical sensors (112, 312) is disposed on the convex top surface (110, 310) of the second frame member (108, 308).

6. The solar tracking cloud radar apparatus (100, 300) as claimed in claim 5, wherein the first frame member (102) and the second frame member (108) are physically connected with other such that the first frame member (102) and the second frame member (108) intersect each other at an intersection point at right angle and the first frame member (102) and the second frame member (108) dissect each other at the intersection point, and wherein a common optical sensor (120) located at the intersection point such that a Z-Z axis passes through the common optical sensor (320), wherein the common optical sensor (320) primarily tracks exact position of the sun while the first set of optical sensors (306) and the second set of optical sensors (312) detect the maximum light intensity spot in the sky, whenever the sun is masked by a cloud.

7. The solar tracking cloud radar apparatus (100, 300) as claimed in claim 1, further comprising a first controller (3760 is configured to compare light intensity received from the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312) respectively to determine the coordinate angle of location of the at least one optical sensor from the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312) with the maximum light intensity spot in the sky whenever sun is masked by a cloud or overcast.

8. The solar tracking cloud radar apparatus (100, 300) as claimed in claim 1, wherein the solar tracking cloud radar apparatus is mounted on a non-rotating type frame.

9. The solar tracking cloud radar apparatus (100, 300) as claimed in claim 1, wherein the solar tracking cloud radar apparatus (100) is mounted on a two-axis rotating type frame (116) constructed on the principle of horizontal primary dual axis tracker (HPDAT), the two- axis rotating type frame (116) comprises: a main frame (226) comprising an E-W arm (232) defining an E-W fulcrum (234) and an N-S arm (236) defining an N-S fulcrum (238); a C-channel assembly (228) integrated with the N-S fulcrum (236) of the main frame (226); pillar(s) (230) for supporting the main frame (226); an E-W drive system (240) for rotating the main frame (226) about the E-W fulcrum (234); and an N-S drive system (258) for rotating the C-channel assembly (228) at about the N-S fulcrum (236).

10. A solar power generation system comprising: a solar tracking cloud radar apparatus (100, 300); and at least one solar photovoltaic panel (214, 314) mounted on at least one two-axis rotating type frame that can be tilted on both the E-W and N-S axes; the solar tracking cloud radar apparatus (100, 300) comprising: a frame member (101, 301) having a convex top surface (104, 110, 303); a first set of optical sensors (106, 306) disposed along a first direction (X-X’) on the convex top surface (104, 110, 303) of the frame member (102, 108, 301); and a second set of optical sensors (112, 312) disposed along a second direction (Y-Y’) on the convex top surface (110, 303) of the frame member (101, 301), the second direction being substantially perpendicular to the first direction, said first set of optical sensors (106, 306) and second set of optical sensors (112, 312) being disposed radially at fixed angle intervals on the convex top surface (110, 303) to provide a coordinate angle of location in X-X’ and Y-Y’ axes respectively of a maximum light intensity spot in the sky whenever sun is masked by a cloud or overcast; a first controller (376i), connected to the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312), configured to determine the coordinate angle of location in X-X’ and Y-Y’ axes of at least one optical sensor from the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312) respectively of a maximum light intensity spot in the sky when sun is masked by the cloud or overcast; and at least one further controller (376₂) configured to receive the coordinate angle from the first controller (376i) to tilt the at least one solar photovoltaic panel (214, 314) based on the coordinate angle to generate maximum power.

11. The solar power generation system as claimed in claim 10, wherein the solar tracking cloud radar apparatus is mounted on the two-axis rotating type frame (116, 316) constructed on the principle of horizontal primary dual axis tracker (HPDAT), the solar tracking cloud radar apparatus comprises a common optical sensor (120, 307).

12. The solar power generation system as claimed in claim 10, wherein the first controller (376i) is connected to the first set of optical sensors (106, 306), the second set of optical sensors (112, 312), the first controller (376_j) being adapted to: receive the inputs from the first set of optical sensors (106, 306), the second set of optical sensors (112, 312) and the common optical sensor (120, 307); tilt the two-axis rotating type frame (316) in accordance with the Open Loop Control System method; determine an exact position of the sun when the sun is not masked by a cloud or overcast; determine the maximum light intensity spot in the sky when the sun is masked by a cloud or overcast, wherein the maximum light intensity spot in the sky may be away from the exact sun’s position; and generate control signals on the basis of determination of the maximum light intensity spot to tilt the at least one solar photovoltaic panel (214, 314).

13. The solar power generation system as claimed in claim 10, comprising at least one further controller (376₂) provided in operational relation with the at least one further two-axis rotating type frame (316), the at least one further controller (376₂) being in operational interconnection with the first controller (376i) for receiving therefrom the control signals, the at least one further controller (376₂) being configured to control the operation of a corresponding E-W drive system and corresponding N-S drive system based on the control signals received from the first controller (3760.

14. The solar power generation system as claimed in claim 10, wherein the first controller (376i) is in operational relation with an E-W drive system and an N-S drive system.

15. A method implemented by a solar generation system as claimed in claim 10, said method comprising: receiving, by a first controller (376i), inputs relating to maximum light intensity spot in sky from the first set of optical sensors (106, 306), the second set of optical sensors (112, 312) respectively; determining, by the first controller (376i), a coordinate angle of location in X-X’ and Y-Y’ axes of at least one optical sensor from the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312) respectively of a maximum light intensity spot in the sky when sun is masked by the cloud or overcast, wherein the maximum light intensity spot in the sky is away from an exact sun’s position; generating, by the first controller (376i), control signals on the basis of the aforesaid determining by the first controller (376i); transmitting, by the first controller (376_j), the control signals to the at least one further controller (376₂); and controlling, by the at least one further controller (370₂), operation of a corresponding E-W drive system and corresponding N-S drive system based on the control signals received from the first controller (3760 to tilt the at least one solar photovoltaic panel (214, 314), wherein the method comprises comparing, by the first controller (376i), light intensity received from the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312) to determine the coordinate angle of location of the at least one optical sensor from the first set of optical sensors (106, 306) and the second set of optical sensors (112, 312) with the maximum light intensity spot when the sun is masked by the cloud or overcast, wherein the at least one further controller (376₂) configured to receive the coordinate angle from the first controller (376i) via an interface (402).