An optimization design method and system of an offshore independent photovoltaic power supply system

Abstract

The application discloses an optimization design method and system of an offshore independent photovoltaic power supply system, and the method comprises the following steps: determining an operation scheme of the independent photovoltaic power supply system based on multiple system factors; calculating effective irradiance and output power of photovoltaic panels received within a preset time according to the operation scheme; determining the capacity of a super capacitor required according to the effective irradiance, the output power and survival conditions; and performing iterative calculation according to the capacity of the super capacitor required to obtain an optimal photovoltaic panel scale. The application can provide energy for survival of marine exploration equipment on the sea surface, and reasonable configuration is obtained in terms of reliability and economy.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic power supply system optimization technology, and in particular to an optimization design method and system for an independent offshore photovoltaic power supply system. Background Technology

[0002] Marine exploration equipment requires electricity to survive on the sea surface, and photovoltaic power systems can provide this energy. However, due to the unique characteristics of the marine environment, photovoltaic power systems face some technical challenges when operating on the sea surface:

[0003] System efficiency is a crucial indicator for evaluating the investment and operational value of photovoltaic (PV) power plants. It encompasses factors such as solar cell aging efficiency, AC / DC low-voltage system losses, inverter efficiency, and transformer and grid losses. Improving the PR value requires understanding and mitigating the factors that influence it. For example, module power degradation, module series-parallel mismatch and shading, losses due to dust and snow accumulation, and temperature coefficient losses in the battery modules all impact system efficiency.

[0004] Energy management and storage: Since marine exploration equipment may operate in areas far from the power grid, effective energy management and storage solutions are required to ensure a continuous and stable power supply.

[0005] Maintenance and monitoring: Maintaining and monitoring offshore photovoltaic systems can be more challenging than onshore systems because accessing offshore locations can be more difficult and expensive. Therefore, there is a need to develop remote monitoring and diagnostic technologies, as well as low-cost, efficient maintenance strategies.

[0006] Economic viability: The cost of offshore photovoltaic projects is usually higher than that of onshore projects. Therefore, technological innovation and large-scale production are needed to reduce costs and improve the economic viability of offshore photovoltaic systems. Summary of the Invention

[0007] The present invention aims to at least partially solve one of the technical problems in the related art.

[0008] Therefore, this invention proposes an optimized design method for an independent photovoltaic power supply system at sea, which can provide energy for marine exploration equipment to survive on the sea surface. The optimized design of the system can achieve a reasonable configuration in terms of reliability and economy.

[0009] Another objective of this invention is to propose an optimized design device for an independent photovoltaic power supply system at sea.

[0010] To achieve the above objectives, this invention proposes an optimized design method for an independent offshore photovoltaic power supply system, comprising:

[0011] The operation scheme of the independent photovoltaic power supply system is determined based on multiple system factors;

[0012] Calculate the effective irradiance and output power received by the photovoltaic panel within a preset time according to the operation plan;

[0013] The required supercapacitor capacity is determined based on the effective irradiance, output power, and survival conditions.

[0014] The optimal photovoltaic panel size is obtained by iterative calculation based on the required supercapacitor capacity.

[0015] To achieve the above objectives, this invention proposes an optimized design system for an independent offshore photovoltaic power supply system, comprising:

[0016] The operation scheme determination module is used to determine the operation scheme of an independent photovoltaic power supply system based on various system factors.

[0017] The irradiance calculation module is used to calculate the effective irradiance and output power received by the photovoltaic panel within a preset time according to the operation plan.

[0018] A capacitor capacity calculation module is used to determine the required supercapacitor capacity based on the effective irradiance, output power, and survival conditions.

[0019] The scale data calculation module is used to perform iterative calculations based on the required supercapacitor capacity to obtain the optimal photovoltaic panel scale.

[0020] The optimized design method and apparatus for an independent offshore photovoltaic power supply system according to embodiments of the present invention can determine the capacity of the supercapacitor based on the system's survivability and load size. Based on the energy output of the photovoltaic panels within a segmented time period and combined with the system requirements, the minimum photovoltaic panel size can be determined through continuous iteration, thereby achieving the optimized design of the system.

[0021] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0022] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0023] Figure 1 This is a flowchart of an optimized design method for an independent offshore photovoltaic power supply system according to an embodiment of the present invention;

[0024] Figure 2 This is a wave spectrum diagram according to an embodiment of the present invention;

[0025] Figure 3 This is a conceptual schematic diagram of the tilt angle and azimuth angle of a photovoltaic panel according to an embodiment of the present invention;

[0026] Figure 4 This is a diagram showing the positional relationship between a photovoltaic panel and the Earth and the Sun according to an embodiment of the present invention;

[0027] Figure 5 This is a conceptual schematic diagram of the solar zenith angle and solar altitude angle according to an embodiment of the present invention;

[0028] Figure 6 It is a graph showing the change of effective irradiance received on a horizontal photovoltaic panel over time according to an embodiment of the present invention;

[0029] Figure 7 This is a graph showing the change in effective irradiance received by a marine photovoltaic panel over time according to an embodiment of the present invention.

[0030] Figure 8 This is a graph showing the change of the maximum output energy of the photovoltaic panel over time according to an embodiment of the present invention;

[0031] Figure 9 This is a flowchart of the photovoltaic module scale design iterative calculation according to an embodiment of the present invention;

[0032] Figure 10 This is a structural diagram of an optimized design device for an independent marine photovoltaic power supply system according to an embodiment of the present invention. Detailed Implementation

[0033] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0034] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0035] The following describes, with reference to the accompanying drawings, an optimized design method and system for an independent offshore photovoltaic power supply system according to an embodiment of the present invention.

[0036] The optimized design method of the offshore independent photovoltaic power supply system according to embodiments of the present invention is as follows: Figure 1 As shown, it includes:

[0037] S1, determine the operation scheme of the independent photovoltaic power supply system based on multiple system factors;

[0038] S2, calculate the effective irradiance and output power received by the photovoltaic panel within a preset time according to the operation plan;

[0039] S3, determine the required supercapacitor capacity based on the effective irradiance, output power, and survival conditions;

[0040] S4, iteratively calculates the required supercapacitor capacity to obtain the optimal photovoltaic panel size.

[0041] Understandably, the tilt angle β and azimuth angle α of the photovoltaic panels on the sea surface are constantly changing, which causes the irradiance received by the photovoltaic panels to also be constantly changing, making it very difficult to calculate the effective irradiance received by the photovoltaic panels.

[0042] The scale of the system can be specifically expressed as: if P pv N represents the maximum power that a photovoltaic panel can produce under STC conditions. pv Let N represent the number of photovoltaic panels. pv P pv This indicates the maximum power that the photovoltaic panel can generate under STC conditions; if C batt N represents the storage capacity of a supercapacitor. batt N represents the number of supercapacitors. batt C batt It refers to the total storage capacity of a supercapacitor.

[0043] Before the calculations, it is necessary to discuss the waveform of the ocean waves, as this determines the curve of the photovoltaic panel's tilt angle β over time. Ocean wave motion is complex, and stochastic processes are often used for simulation in its study. Any point on the sea surface can be considered as the superposition of countless wave initiation sources, as expressed in the following formula:

[0044]

[0045] In the formula a n —Amplitude (m) of any wave initiation waveform; ω n —The angular frequency (rad / s) of any wave initiation waveform; ε n — The initial phase (rad) of any wave waveform; n — the number of waves.

[0046] From a spectral analysis perspective, this invention uses a simple PM (Pierson-Moscowitz) spectrum to obtain the energy density of ocean waves at different frequencies, thus:

[0047]

[0048] In the formula S(ω) w —Unit frequency interval Δω w The energy within, i.e., energy density (m 2 s); ω w — Angular frequency of ocean waves (rad / s); g — Acceleration due to gravity (m / s²) 2 );V w —This is the wind speed (m / s) at a height of 19.5 meters above sea level; a and b —are coefficients, each 8.1 × 10⁻⁶. -3 And 0.74.

[0049] The frequency corresponding to the spectral peak is 8.565V. w Assume V w =10m / s, which can be obtained through simulation. Figure 2 The wave spectrum curves shown in the figure indicate that, at a certain wind speed, the frequency of the composite wave after wave superposition is mainly concentrated in a very small range.

[0050] If we can collect daily daytime irradiance information, calculate the average irradiance value within time Δt throughout the day, and then integrate and average it, we can obtain the effective irradiance within Δt. Furthermore, we can obtain the curve G showing the variation of the effective irradiance received on the horizontal surface during the day with time t. h(t) .

[0051] However, at present, it is impossible to collect such detailed data. The data available on NASA's official website only shows the average daily total radiation (G) received on the horizontal plane at a specific location (longitude and latitude determined) over a month. h(total) The total radiation dose can be calculated using the following formula:

[0052]

[0053] In the formula, t1 is the sunrise time and t2 is the sunset time.

[0054] The tilt angle β and azimuth angle α of the photovoltaic panels on the sea surface are constantly changing, so the total irradiance G received by the photovoltaic panels is constantly changing. pv(total) It needs to be obtained after some conversion. Figure 3 The concepts of β and α can be seen intuitively.

[0055] Where, θ S This is the angle of incidence of sunlight. According to G... h(total) Calculate G pv(total) The specific method is as follows:

[0056] (1) Calculate the effective irradiance received by the horizontal surface in the segmented time: total irradiance G(0), direct irradiance B(0) and diffuse irradiance D(0);

[0057] (2) Converted into the effective irradiance received on the offshore photovoltaic panels: total irradiance G(β,α), direct irradiance B(β,α), diffuse irradiance D(β,α) and reflected irradiance R(β,α);

[0058] (3) By integrating the total irradiance G(β,α) over the segmented time from sunrise to sunset, the total irradiance G received by the photovoltaic panel can be obtained. pv(total) .

[0059] Based on the number of days d from the beginning of the year n The latitude δ of the subsolar point on that day can be calculated using the following formula (positive for north and negative for south):

[0060]

[0061] At this time, the positional relationship between the photovoltaic panel and the Earth and the Sun is as follows: Figure 4 As shown, the solar zenith angle θ ZS and solar altitude angle γ S like Figure 5 As shown.

[0062] Solar altitude angle γ S It is given by the following formula:

[0063] sinγ S =sinδsinφ+cosδcosφcosω(3-5)

[0064] In the formula —Latitude (degrees) of the photovoltaic panel; ω —represents the difference (degrees) between the longitude of the subsolar point and the longitude of the highest solar altitude angle (i.e., noon), with 0 for noon, negative for morning, and positive for afternoon. When the solar altitude angle is zero, the sunrise angle ω can be calculated. S :

[0065] ω S = -arccos(-tanδtanφ)(3-6)

[0066] Of course, the sunset angle is -ω S .

[0067] The external irradiance B0(0) on a horizontal surface can be given by the following formula:

[0068] B0(0)=B0ε0sinγ S (3-7)

[0069]

[0070] In the formula, B0 represents the energy received per unit area perpendicular to the incident light outside the atmosphere, taken as 1367 W / m². 2 ε0— Deviation correction factor.

[0071] Integrating the external irradiance B0(0), since ω is linearly proportional to time, the integral over time can be transformed into an integral over ω, yielding the total daily external irradiance B. 0d (0):

[0072]

[0073] In the formula, T represents the number of hours in a day, i.e., 24 hours; the monthly average value B is obtained by calculating the total daily external radiation and summing and averaging it. 0dm (0).

[0074] The relationship between the Earth's surface and extraterrestrial radiation characterizes atmospheric transparency, which can be expressed by the clear sky index K. Tm To express:

[0075]

[0076] According to the clear sky index K Tm The proportionality coefficient F can be obtained. Dm (Diffuse radiation / Total radiation):

[0077] F Dm =1-1.13K Tm (3-11)

[0078] Therefore, according to G h(total) The size can be used to obtain the total amount of direct irradiation B. h(total) Total diffuse irradiation D h(total) Daily irradiance can be segmented into hourly irradiance. Outside the atmosphere, irradiance B0(0) and daily irradiance B 0d The relationship between (0) is shown below:

[0079]

[0080] Based on data observations from several locations on the ground, it was found that the diffuse irradiance D(0) and the daily diffuse irradiance D h(total) The relationship between them agrees well with formula (3-12), and the total irradiance G(0) and the total daily radiation G h(total) The relationship between them deviates somewhat from formula (3-12), but it can still be applied well after correction. The relationship is as follows:

[0081]

[0082] In the formula, a is a coefficient, a = 0.409 - 0.5016sin(ω S +60°); b—coefficient, b=0.6609-0.4767sin(ω S +60°).

[0083] The curve showing the change in effective irradiance received by a horizontal photovoltaic panel over time is as follows: Figure 6 As shown.

[0084] The expression for direct irradiance is as follows:

[0085]

[0086] In the formula θ S —The angle of incidence between sunlight and the surface normal. The cosine of the angle of incidence, cosθ. S It is given by the following formula:

[0087]

[0088] When the equipment is in the Northern Hemisphere, Therefore:

[0089]

[0090] During the piecewise time intervals, ω, δ, and Both can be considered constants, and can be set as follows: E=cosδsinω, simplifying formula (3-18) yields:

[0091] cosθ S =Acosβ-Bsinβcosa+Ccosβ+Dsinβcosa+Esinβsina(3-19)

[0092] The tilt angle and azimuth angle of photovoltaic panels exhibit certain regularities. Under sea state timescales, the wind direction and force at sea can be considered constant; therefore, the azimuth angle α can be considered constant over a segmented time period. The tilt angle of the photovoltaic panel can be roughly expressed as an odd function β(t)∈[-θ,θ], which changes periodically with time t. θ )=-β(-t θ If θ = 0, then cosθ can be obtained. S The average value.

[0093]

[0094] The formula for calculating diffuse radiation is (3-21). When considering its direct radiation component, the formula for calculating diffuse radiation is (3-22).

[0095]

[0096] The distribution ratio of the two components is determined by the isotropic index k1.

[0097]

[0098] Therefore, diffuse irradiance can be expressed as:

[0099] D(β, a) = D I (β,a)+D c (β,a) (3-24)

[0100]

[0101] Since the tilt angle changes periodically, it is necessary to perform integral averaging on formulas (3-25) and (3-26) to obtain their effective values.

[0102] When considering reflected radiation, it is generally assumed that the ground is infinitely horizontal and that the reflected light is isotropic. Therefore:

[0103]

[0104] In the formula, ρ represents the reflectivity of the ground, which depends on the composition of the ground. When it is unknown, it is generally taken as 0.2.

[0105] Therefore, after substituting the values ​​of A and C into formula (3-20), we can obtain the following expression:

[0106]

[0107] Curves Figure 7 As shown, G can be calculated. pv(total) It is 5701.82Wh / m 2 .and Figure 6 In comparison, the effective irradiance received by offshore photovoltaic panels is reduced.

[0108] Assume that the optimal output voltage and optimal output current of the photovoltaic panel under STC are respectively V mpp,ref and I mpp,ref However, under non-standard testing conditions, the optimal output current and optimal output voltage of photovoltaic panels are affected by actual irradiance and temperature, thus:

[0109]

[0110] V mpp (G,T m ) = V mpp,ref [1-c(T m -T ref )]ln[e+b(GGref (3-30)

[0111] Generally speaking, the temperature T of a photovoltaic panel m Much higher than the ambient temperature T air The following formula can be used to express this:

[0112] T m =T air +θ G (1+θ air T air (1+θ) w V w )G (3-31)

[0113] In the formula θ G θ air θ w —The constants determined experimentally are 0.0138, 0.031, and 0.042, respectively. V w —Wind speed (m / s);

[0114] Ambient temperature T air It is a function that changes over time and can be simulated using a sine function.

[0115]

[0116] In the formula T air,max —The highest ambient temperature of the day (°C); T air,min —The lowest ambient temperature of the day (°C).

[0117] Therefore, the maximum output power P under non-standard conditions can be obtained. pv,max (G,T m ).

[0118] P pv,max (G,T m ) = I mpp (G,T m ).V mpp (G,T m (3-33)

[0119] Continuing the calculations above, the maximum output energy E can be obtained. pv,max (G,T m The variation of ω is shown in the curve below. Figure 8 As shown, the maximum output electrical energy is E. pv,max(total) =187263J. Considering the efficiency η of MPPT technology. mppt The actual output power E of the photovoltaic panel can be obtained. pv (G,T mIntegrating this yields the total energy E generated by the photovoltaic panel. pv(total) .

[0120] The goal of the system optimization design of this invention is to ensure that the load in the system can operate continuously around the clock, that is, the power failure rate (LPSP) is zero, and only then is the economic efficiency of the system considered.

[0121] LPSP=Pr{E B (t)≤E Bmin ;for t≤T}=0 (3-34)

[0122] In the formula E B (t)——Energy stored in the supercapacitor at time t (J); E Bmin —The minimum allowable energy storage capacity of a supercapacitor (J).

[0123] Considering the harsh conditions the system needs to withstand, it is assumed here that the system may experience N consecutive days without sunlight. During this period, the energy storage of the supercapacitor must always satisfy formula (3-34). In normal operation mode, the system charges the supercapacitor to its nominal voltage V during the daytime. N Then charging is stopped until the supercapacitor voltage drops to a certain value V. N,ref The system only recharges the capacitor at this time, therefore the supercapacitor's energy storage should be maintained at at least 0.5N before nightfall. batt C batt (V N,ref ) 2 Therefore, the energy storage capacity of a supercapacitor can be derived from the following formula:

[0124]

[0125] In the formula η s —Self-discharge coefficient of the supercapacitor; N —Number of days the system can survive in the absence of light. η batt,out —Discharge efficiency of supercapacitors, P Lnight — Load power (W) of the system during nighttime operation.

[0126] The energy harvested by photovoltaic panels during the day must not only ensure the normal operation of the system during the day, but also ensure that the energy storage capacity of the supercapacitor is reduced to E. Bmin Furthermore, the supercapacitor must reach an energy storage capacity of 0.5N before nightfall. batt C batt (V N,ref ) 2 .

[0127] Following the previous time segmentation number n, this invention iterates the same number of times, checking whether the supercapacitor's energy storage meets the requirements in each iteration. The charging and discharging formulas for the supercapacitor are formulas (3-36) and (3-37), respectively. The specific iterative calculation process is as follows: Figure 9 As shown.

[0128]

[0129]

[0130] In the formula E B (k)——The kth supercapacitor energy storage (J); P Lday —Daytime load power (W);

[0131] t day —Daytime duration (h); η batt,in —Supercapacitor charging efficiency.

[0132] According to the optimization design method of the offshore independent photovoltaic power supply system of the present invention, the capacity of the supercapacitor can be determined based on the survivability of the system and the load size. Based on the energy output of the photovoltaic panels in segmented time periods and combined with the requirements of the system, the minimum scale of the photovoltaic panels can be determined through continuous iteration, thereby realizing the optimization design of the system.

[0133] like Figure 10 As shown, to achieve the above objectives, the present invention proposes an optimized design system 10 for an independent offshore photovoltaic power supply system, comprising:

[0134] The operation scheme determination module 100 is used to determine the operation scheme of an independent photovoltaic power supply system based on multiple system factors.

[0135] The irradiance calculation module 200 is used to calculate the effective irradiance and output power received by the photovoltaic panel within a preset time according to the operation plan.

[0136] The capacitance calculation module 300 is used to determine the required supercapacitor capacity based on the effective irradiance, output power, and survival conditions.

[0137] The scale data calculation module 400 is used to perform iterative calculations based on the required supercapacitor capacity to obtain the optimal photovoltaic panel scale.

[0138] According to the optimization design method of the offshore independent photovoltaic power supply system of the present invention, the capacity of the supercapacitor can be determined based on the survivability of the system and the load size. Based on the energy output of the photovoltaic panels in segmented time periods and combined with the requirements of the system, the minimum scale of the photovoltaic panels can be determined through continuous iteration, thereby realizing the optimization design of the system.

[0139] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0140] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

Claims

1. An optimized design method for an independent offshore photovoltaic power supply system, characterized in that, include: The operation scheme of the independent photovoltaic power supply system is determined based on multiple system factors; Calculate the effective irradiance and output power received by the photovoltaic panel within a preset time according to the operation plan; The required supercapacitor capacity is determined based on the effective irradiance, output power, and survival conditions. The optimal photovoltaic panel size is obtained by iterative calculation based on the required supercapacitor capacity.

2. The method according to claim 1, characterized in that, The energy density of ocean waves at different frequencies was obtained using the PM spectrum. In the formula S(ω) w ) is the unit frequency interval Δω w The energy within, i.e., energy density; ω w V is the angular frequency of the ocean waves; g is the acceleration due to gravity; V w It refers to the wind speed over the sea; a and b are coefficients. Calculate the total radiation: In the formula, t1 is the sunrise time; t2 is the sunset time.

3. The method according to claim 1, characterized in that, Total irradiance G received by the photovoltaic panel pv(total) θ is obtained after transformation. S Let G be the angle of incidence of sunlight. h(total) Calculate G pv(total) ,include: Calculate the effective irradiance received by the horizontal surface in segmented time intervals: total irradiance G(0), direct irradiance B(0), and diffuse irradiance D(0); Converted into the effective irradiance received on the offshore photovoltaic panels: total irradiance G(β,α), direct irradiance B(β,α), diffuse irradiance D(β,α) and reflected irradiance R(β,α); The total irradiance G(β,α) received on the photovoltaic panel is obtained by integrating the total irradiance G(β,α) over a segmented time period from sunrise to sunset. pv(total) .

4. The method according to claim 1, characterized in that, Based on the number of days d from the beginning of the year n The latitude δ of the subsolar point on that day can be obtained using the following formula: Solar altitude angle γ S It is given by the following formula: sinγ S =sinδsinφ+cosδcosφcosω In the formula ω represents the latitude of the photovoltaic panel; ω is the difference between the longitude of the subsolar point and the longitude of the highest solar altitude angle during the day, 0 at noon, negative in the morning, and positive in the afternoon; when the solar altitude angle is zero, the sunrise angle ω is obtained. S : oh S =-arccos(-tanδtanφ) Sunset angle is -ω S ; The external irradiance B0(0) on a horizontal surface is given by the following formula: B0(0)=B0ε0sinγ S In the formula, B0 is the energy received per unit area outside the atmosphere perpendicular to the incident light, and ε0 is the deviation correction factor. Transforming the integral over time into the integral over ω, we obtain the total daily extraterrestrial radiation B. 0d (0): In the formula, T represents the number of hours in a day; The relationship between Earth's surface and extraterrestrial radiation characterizes atmospheric transparency, expressed by the clear sky index K. Tm Express: According to the clear sky index K Tm Obtain the proportionality coefficient F Dm : F Dm =1-1.13K Tm According to G h(total) The size of the direct irradiation total B is obtained h(total) Total diffuse irradiation D h(total) Daily radiation can be broken down into hourly radiation. Outside the atmosphere, irradiance B0(0) and daily irradiance B 0d The relationship between (0) is shown below: The revised relation is as follows: B(0) = G(0) - D(0).

5. The method according to claim 1, wherein the expression for direct irradiance is as follows: In the formula θ S It is the angle of incidence between sunlight and the surface normal.

6. The method according to claim 1, assuming that the optimal output voltage and optimal output current of the photovoltaic panel under STC are respectively V mpp,ref and I mpp,ref Under non-standard testing conditions, the optimal output current and optimal output voltage of photovoltaic panels are affected by actual irradiance and temperature. V mpp (G,T m )=V mpp，ref [1-c(T m -T ref )]ln[e+b(G-G re )]。 7. According to the method described in claim 1, the energy storage capacity of the supercapacitor is derived using the formula: In the formula, η s η is the self-discharge coefficient of the supercapacitor; N is the number of days the system can survive under no-light conditions; η is the number of days the system can survive. batt,out This refers to the discharge efficiency of the supercapacitor; P Lnight This is the load power of the system when it is running at night.

8. According to the method described in claim 1, the charging and discharging formulas for the supercapacitor are as follows: In the formula, E B (k) represents the k-th supercapacitor energy storage; P Lday This is the load power during the day; t day It refers to the length of daytime; η batt,in It refers to the charging efficiency of supercapacitors.

9. An optimized design system for an independent offshore photovoltaic power supply system, characterized in that, include: The operation scheme determination module is used to determine the operation scheme of an independent photovoltaic power supply system based on various system factors. The irradiance calculation module is used to calculate the effective irradiance and output power received by the photovoltaic panel within a preset time according to the operation plan. A capacitor capacity calculation module is used to determine the required supercapacitor capacity based on the effective irradiance, output power, and survival conditions. The scale data calculation module is used to perform iterative calculations based on the required supercapacitor capacity to obtain the optimal photovoltaic panel scale.

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