Photovoltaic flexible power rapid tracking method, device and system, and storage medium
By using the dynamic current secant method to iteratively calculate the target current of the photovoltaic array, the applicability problem of the traditional flexible power point tracking algorithm under shading conditions is solved, achieving fast and stable power tracking and improving the stability and applicability of the photovoltaic power generation system.
Patent Information
- Application Number
- CN202511860991.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-11
- Publication Date
- 2026-04-24
AI Technical Summary
Traditional flexible power point tracking algorithms are not applicable under photovoltaic shading conditions, and existing methods have room for improvement in terms of overall adaptability and robustness to complex operating conditions.
The dynamic current secant method is adopted to iteratively calculate the target current based on the current output voltage, current and reference power of the photovoltaic array, and control the photovoltaic array to track the target current to achieve power tracking. The constant voltage characteristic of the high voltage side of the photovoltaic array at the maximum power point is used for rapid iteration.
It achieves faster power point tracking speed, improves the stability of photovoltaic power generation under complex operating conditions, avoids power oscillation, reduces the requirements for processor performance, and is suitable for various photovoltaic power generation structures.
Smart Images
Figure CN121918665A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of power control technology, specifically to a photovoltaic flexible power tracking method, device, system, and storage medium. Background Technology
[0002] Photovoltaic (PV) power generation, with its significant advantages of being clean and renewable, has seen its share in the energy sector continue to rise. With the rapid penetration of distributed renewable energy, PV power generation has become the most important new energy form in microgrids and distribution substations. However, PV power is significantly affected by natural factors such as sunlight and temperature, exhibiting randomness and volatility. When a large number of PV systems are connected to the grid, it can easily lead to increased frequency deviation in the microgrid, intensifying frequency regulation pressure and affecting the synchronization stability of multiple microgrid groups. The Flexible Power Point Tracking (FPPT) technology, proposed in recent years, provides a feasible way to achieve active adjustment of PV power and its participation in system frequency regulation. By operating outside the maximum power point, PV modules can output specified power according to dispatch instructions, achieving frequency regulation requirements such as peak shaving, valley filling, and reserved power.
[0003] Traditional flexible power point tracking (WPPT) algorithms employ a perturbation-observation-like logic, which may be unsuitable for photovoltaic (PV) shading conditions. Some strategies based on illumination change detection collect PV voltage, current, and power tracking mode commands, perform real-time illumination detection, and determine the reference voltage based on the illumination state, flexible power, and global maximum power. This is suitable for partially shaded scenarios but increases costs. Binary Nonlinear Search (BNS) algorithms treat power and voltage as a sorted dataset, using logarithmic search to locate the target value. The search window is dynamically adjusted based on calculation errors and voltage increments, shortening convergence time and avoiding steady-state oscillations. Some methods rely on PV models, such as data-driven methods, which collect voltage and current to calculate power, compare it to the reference power to determine the WPPT tracking status, and apply perturbations to estimate the gradient, update, and filter the voltage when not tracking, thus eliminating PV model dependence. Linear jump-based strategies calculate the linear slope to the left of the maximum power point to determine the jump current and reference voltage. Based on the relationship between the reference power and available power, fast tracking is achieved through direct jumps or in combination with MPPT. These methods optimize FPPT from different dimensions, and each has made breakthroughs in tracking flexibility, response speed and model dependency. However, there is still room for synergistic improvement in dimensions such as comprehensive adaptability and robustness in complex working conditions. Summary of the Invention
[0004] This application provides a photovoltaic flexible power tracking method, device, system, and storage medium.
[0005] The first aspect of this application provides a photovoltaic flexible power tracking method, comprising:
[0006] Obtain the current output power of the photovoltaic array;
[0007] The current search direction for power tracking is determined based on the relationship between the current output power of the photovoltaic array and the reference power.
[0008] Based on the current search direction, and based on the current output voltage, current output and reference power of the photovoltaic array, the target current is iteratively calculated; the photovoltaic array is controlled to track the target current in order to perform power tracking.
[0009] In an optional embodiment of this application, determining the current search direction for power tracking based on the relationship between the current output power of the photovoltaic array and the reference power includes:
[0010] If the current output power is lower than the reference power, the search proceeds in the direction of increasing current; if the current output power is higher than the reference power, the search proceeds in the direction of decreasing current.
[0011] In an optional embodiment of this application, based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, based on the current output voltage, current output current, and reference power of the photovoltaic array; controlling the photovoltaic array to track the target current for power point tracking includes:
[0012] The target current is calculated iteratively using the dynamic current secant method.
[0013] In an optional embodiment of this application, based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, based on the current output voltage, current output current, and reference power of the photovoltaic array; controlling the photovoltaic array to track the target current for power point tracking includes:
[0014] The calculation formula for the dynamic current secant method is as follows:
[0015]
[0016] In the formula, I k+1 I is the target current value after iteration. k P is the current output current. ref For reference power, P pv For the current output power, I cal and P cal These are used to calculate the reference point current and power values, respectively.
[0017] In an optional embodiment of this application, based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, based on the current output voltage, current output current, and reference power of the photovoltaic array; controlling the photovoltaic array to track the target current for power point tracking includes:
[0018] The permitted operating area for tracking is limited to the high-voltage side of the photovoltaic array at its current maximum power point.
[0019] In an optional embodiment of this application, based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, based on the current output voltage, current output current, and reference power of the photovoltaic array; controlling the photovoltaic array to track the target current for power point tracking includes:
[0020] If the error index between the current output power and the reference power is less than the preset power tracking error, then the iteration stops and the current output current is maintained.
[0021] In an optional embodiment of this application, based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, based on the current output voltage, current output current, and reference power of the photovoltaic array; controlling the photovoltaic array to track the target current for power point tracking includes:
[0022] The error index is calculated using the following formula:
[0023]
[0024] In the formula, e k ε is the error index, and ε is the preset power tracking error.
[0025] In an optional embodiment of this application, based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, based on the current output voltage, current output current, and reference power of the photovoltaic array; controlling the photovoltaic array to track the target current for power point tracking includes:
[0026] If the power is detected to be insufficient to meet the preset requirements during power point tracking, the system will switch to maximum power point tracking mode.
[0027] In an optional embodiment of this application, based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, based on the current output voltage, current output current, and reference power of the photovoltaic array; controlling the photovoltaic array to track the target current for power point tracking includes:
[0028] If the target current obtained by iterative calculation is greater than the current maximum power point current of the photovoltaic array, and the corresponding current output power is still less than the reference power, then control the photovoltaic array to switch to maximum power point tracking mode.
[0029] In an optional embodiment of this application, based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, based on the current output voltage, current output current, and reference power of the photovoltaic array; controlling the photovoltaic array to track the target current for power point tracking includes:
[0030] When switched to maximum power point tracking mode, it continuously performs local maximum power point search to maintain the maximum power output of the photovoltaic array.
[0031] In an optional embodiment of this application, based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, based on the current output voltage, current output current, and reference power of the photovoltaic array; controlling the photovoltaic array to track the target current for power point tracking includes:
[0032] The maximum value of the target current is set to the recorded global maximum power point current of the photovoltaic array.
[0033] In an optional embodiment of this application, based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, based on the current output voltage, current output current, and reference power of the photovoltaic array; controlling the photovoltaic array to track the target current for power point tracking includes:
[0034] When the reference power undergoes a step change, the iterative calculation is repeated.
[0035] In an optional embodiment of this application, based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, based on the current output voltage, current output current, and reference power of the photovoltaic array; controlling the photovoltaic array to track the target current for power point tracking includes:
[0036] The reference power is dynamically issued by either the central controller or the local controller of the microgrid cluster based on the system frequency regulation requirements.
[0037] A second aspect of the present application provides a photovoltaic flexible power tracking device, including a processor and a memory storing program instructions. The processor is configured to execute the photovoltaic flexible power tracking method as described in the first aspect of the present application when running the program instructions.
[0038] A third aspect of this application provides a system comprising:
[0039] The system itself; and,
[0040] The photovoltaic flexible power tracking device, as described in the second aspect of this application, is installed on the system body.
[0041] A fourth aspect of the embodiments of this application provides a computer-readable storage medium storing program instructions, which, when executed, cause a computer to perform the photovoltaic flexible power tracking method as described in the first aspect of the embodiments of this application.
[0042] The photovoltaic flexible power tracking method, apparatus, system, and storage medium provided in the embodiments of this application have the following beneficial effects:
[0043] This application's embodiments utilize the constant voltage characteristic of the high-voltage side at the maximum power point of the photovoltaic array to perform rapid iteration of the reference current, achieving faster power point tracking speed. During steady-state operation, there is no power oscillation, improving the stability of photovoltaic power generation under complex operating conditions. It effectively solves the problem of the system being susceptible to environmental changes and potentially falling into an open-circuit state when operating to the right of the maximum power point, thus enhancing the system's stable operation capability. It does not require limitations from inherent photovoltaic open-circuit voltage or other characteristic parameters, eliminating reliance on historical data storage, lowering processor performance requirements, and making it suitable for various photovoltaic power generation structures, thus enhancing its engineering practicality. Attached Figure Description
[0044] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:
[0045] Figure 1 This is a schematic diagram of the photovoltaic flexible power tracking method provided in the embodiments of this application;
[0046] Figure 2 This is an algorithm flowchart of the photovoltaic flexible power tracking method provided in the embodiments of this application;
[0047] Figure 3 This is a schematic diagram of the photovoltaic power generation system provided in the embodiments of this application;
[0048] Figure 4 This is a schematic diagram of the search process for power tracking when the current photovoltaic output power is greater than the reference power, provided in an embodiment of this application.
[0049] Figure 5 This is a schematic diagram of the search process for power tracking when the current photovoltaic output power is less than the reference power, provided in an embodiment of this application.
[0050] Figure 6 This is the PV characteristic curve of the photovoltaic array output under shading conditions provided in the embodiments of this application;
[0051] Figure 7 These are experimental waveforms for tracking step changes in the output power of a photovoltaic array, provided in the embodiments of this application.
[0052] Figure 8 This describes the changes in photovoltaic (PV) curves under different illumination conditions provided in the embodiments of this application.
[0053] Figure 9 These are experimental waveforms provided in this application embodiment, demonstrating the rapid switching and stable operation of photovoltaics under different operating conditions in a scenario of rapidly changing light conditions;
[0054] Figure 10 This is a schematic diagram of a photovoltaic flexible power tracking device provided in an embodiment of this application.
[0055] Figure label:
[0056] 800: Photovoltaic flexible power tracking device; 801: Processor; 802: Memory; 803: Communication interface; 804: Bus. Detailed Implementation
[0057] To make the technical solutions and advantages of the embodiments of this application clearer, the exemplary embodiments of this application will be described in further detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not an exhaustive list of all embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.
[0058] Figure 1 This is a schematic diagram of the photovoltaic flexible power tracking method provided in the embodiments of this application. The method can be executed in the system or in a server or terminal device that is connected to the system.
[0059] Combination Figure 1 As shown in the figure, this application provides a photovoltaic flexible power tracking fast tracking method, including:
[0060] S1, obtain the current output power of the photovoltaic array;
[0061] S2, determine the current search direction for power tracking based on the relationship between the current output power of the photovoltaic array and the reference power;
[0062] In one optional embodiment of this application, if the current output power is lower than the reference power, the search proceeds in the direction of increasing current; if the current output power is higher than the reference power, the search proceeds in the direction of decreasing current.
[0063] S3, based on the current search direction, and based on the current output voltage, current output current and reference power of the photovoltaic array, iteratively calculates the target current; controls the photovoltaic array to track the target current in order to perform power tracking.
[0064] In an optional embodiment of this application, the target current is calculated iteratively using the dynamic current secant method.
[0065] In an optional embodiment of this application, the calculation formula for the dynamic current secant method is as follows:
[0066]
[0067] In the formula, I k+1 I is the target current value after iteration. k P is the current output current. ref For reference power, P pv For the current output power, I cal and P cal These are used to calculate the reference point current and power values, respectively.
[0068] In an optional embodiment of this application, the permitted operating area for tracking is limited to the high-voltage side of the photovoltaic array at its current maximum power point.
[0069] In an optional embodiment of this application, if the error index between the current output power and the reference power is less than a preset power tracking error, the iteration is stopped and the current output current is maintained.
[0070] In an optional embodiment of this application, the error index is calculated using the following formula:
[0071]
[0072] In the formula, e k ε is the error index, and ε is the preset power tracking error.
[0073] In an optional embodiment of this application, if it is detected during power tracking that the power cannot meet the preset requirements, the system switches to maximum power point tracking mode.
[0074] In an optional embodiment of this application, if the target current obtained by iterative calculation is greater than the current maximum power point current value of the photovoltaic array, and the corresponding current output power is still less than the reference power, then the photovoltaic array is controlled to switch to maximum power point tracking mode.
[0075] In one optional embodiment of this application, after switching to maximum power point tracking mode, a local maximum power point search is continuously performed to maintain the maximum power output of the photovoltaic array.
[0076] In an optional embodiment of this application, the maximum value of the target current is set to the recorded global maximum power point current of the photovoltaic array.
[0077] In an optional embodiment of this application, the iterative calculation is re-performed when the reference power undergoes a step change.
[0078] In one optional embodiment of this application, the reference power is dynamically issued by either the microgrid group central controller or the local controller according to the system frequency regulation requirements.
[0079] In this embodiment of the application, the current output power P of the photovoltaic array is obtained. pv Determine whether it has reached the preset reference power P. ref If yes, maintain the current power output mode; otherwise, initiate global flexible power point tracking. The steps for global flexible power point tracking include:
[0080] The initial power tracking direction is determined based on the output characteristics of the photovoltaic array. If the current operating power is lower than the reference power, the search proceeds in the direction of increasing current; if the current operating power is higher than the reference power, the search proceeds in the direction of decreasing current. This determination is based on the constant voltage characteristic of the high-voltage side of the photovoltaic array at its maximum power point.
[0081] Using the dynamic current secant method, based on the output voltage V of the photovoltaic array pv and current I pv The parameters are used to construct a secant line between the current operating point and the reference point to calculate the new target current value I. k+1 .
[0082] Figure 2 This application provides a flowchart of a photovoltaic flexible power tracking method for synchronous frequency regulation of a microgrid group. In specific implementation, initialization is first performed, photovoltaic voltage and current parameters are acquired, and the current photovoltaic power is calculated. If the current power P... pv Less than the required reference power P received ref The algorithm will perform maximum power point tracking (MPPT) until it finds the global maximum power point of the photovoltaic system under shading conditions. After finding the maximum power point, it will continuously perform local MPPT to maintain maximum power output. During reference power tracking, the current power reaches the reference power and the reference power P... ref There is no change; the system maintains the currently set reference current. The mathematical basis for this judgment is:
[0083]
[0084] In the formula, e k ε is the error index between the current photovoltaic power and the reference output power, and ε is the set power tracking error.
[0085] Furthermore, if the reference power P ref If changes occur, flexible power point tracking is performed. This method sets the flexible power point tracking range to the high-voltage side of the photovoltaic array's maximum power point. Within this operating region, the current is:
[0086] 0 < I pv <I mpp
[0087] In the formula, I mpp The maximum power point current value of the photovoltaic array is used. If the tracked operating point does not meet the operating area requirements, that is, if the output power is still less than the recorded maximum power point power when the photovoltaic array current is greater than the maximum power point current, it is considered that the maximum power of the photovoltaic array cannot meet the reference power requirement, and the system will operate in maximum power tracking mode to output the maximum power.
[0088] Figure 3 The schematic diagram of the photovoltaic power generation system provided in this application embodiment includes a photovoltaic array, a DC-DC converter circuit, and a grid-connected inverter circuit. The photovoltaic array converts solar energy into electrical energy, the DC-DC converter circuit, under the control of the drive signal generated by the controller, converts the photovoltaic power to the high-voltage side, and the inverter circuit transmits the power generated by the photovoltaic to the power grid.
[0089] Figure 4 This diagram illustrates the search process for power tracking when the current photovoltaic output power exceeds the reference power, as provided in this embodiment of the application. Point A in the diagram represents the initial photovoltaic operating point. Upon receiving a command to change the reference power, the target current value is iterated according to the following formula:
[0090]
[0091] In the formula, I k+1 For the new target current value, I k P is the current value. ref For reference power, P pv I represents the current power value of the photovoltaic array. cal and P cal The reference point current and power values are calculated separately. The new target current value I is obtained by substituting the voltage at point A into the calculation. B The converter tracks the corresponding current value according to the new current command. At this time, the photovoltaic system operates at point B, and the photovoltaic power P... B Greater than the reference power P ref The algorithm continues to iterate over the target current value, substituting the voltage at point B into the formula to calculate the target current I. C =P ref / V B The photovoltaic operating point then jumps to point C. At this point, the photovoltaic power is greater than the reference power. Substituting the voltage at point C into the calculation, the target current I is obtained. D =P ref / V CAfter the photovoltaic current jumps, the system operates at point D. Since point C is already in the same constant voltage range as the operating point corresponding to the reference power, the target current value calculated in this iteration is close to the reference current value, and the power at point D reaches the set value P. ref Fast tracking of the power reduction direction was achieved through a finite-step iterative process.
[0092] Figure 5 This is a schematic diagram illustrating the power tracking search process when the current photovoltaic output power is less than the reference power, as provided in an embodiment of this application. The photovoltaic system initially operates at point A, where the power is relatively low. ref After modification, the target current I is updated by iteratively applying an iterative formula. B =P ref / V A The converter control current tracks I B Then, the photovoltaic system switches to operating point B, and so on, to achieve tracking of the direction of photovoltaic power increase.
[0093] When the latest target current I k+1 Greater than the recorded maximum power point current I of the photovoltaic array mpp Furthermore, at this operating point, the photovoltaic power is still less than the reference power, indicating that the maximum photovoltaic power cannot meet the requirements, thus causing the photovoltaic system to operate in maximum power point tracking (MPPT) mode. At point C, it is detected that the current operating point satisfies the above mode switching logic; the operating point is located in the non-power point tracking region, and the algorithm will switch to maximum power point tracking mode, outputting the reference current value I. k It is set to the previously recorded maximum power point current value and MPPT tracking is performed to maximize output power.
[0094] To more clearly demonstrate the implementation effect of the photovoltaic flexible power tracking method for synchronous frequency regulation of microgrid groups provided in the embodiments of this application, an experimental study was conducted on the photovoltaic maximum power tracking effect under shading conditions. Figure 6 To present the PV characteristic curve of the photovoltaic array under shading conditions, the experiment employed a step-change condition for the photovoltaic output reference power. The given reference power was varied in a step manner, corresponding to... Figure 6 Working points a, b, c, and d in the diagram.
[0095] Figure 7This is an experimental waveform for step-tracking of the photovoltaic array's output power. Initially, the reference power of the series-connected photovoltaic array is set to 400W. This reference power value is greater than the maximum output power of the photovoltaic array, and the photovoltaic array operates in maximum power point tracking (MPPT) mode, maintaining maximum power output. In the next action, the reference power steps from 400W to 200W, entering MPPT mode. After 0.5s, it tracks the 200W output power. Subsequently, the controller command causes the reference power to step to 100W, continuing the iteration towards decreasing power. The current decreases, and after 0.2s, the set power of 100W is reached, operating in maximum power point tracking mode. Figure 6 Point c in the algorithm; finally, the photovoltaic array output reference power is stepped to 400W. This reference power exceeds the maximum power that the photovoltaic array can output. The algorithm detects that the working area requirements are not met and starts the maximum power tracking process. The maximum power point is reached in 0.5s, and the output power is 330W.
[0096] Figure 8 The PV curves of the photovoltaic array under different illumination conditions are shown below. The PV characteristics of the photovoltaic array under different illumination conditions are curves from condition I to condition 4.
[0097] Figure 9 This is an experimental waveform showing the rapid switching and stable operation of a photovoltaic (PV) system under different operating conditions in a scenario with rapidly changing illumination. Initially, the PV characteristic curve corresponds to Condition I, where the curve has three extreme values. The maximum power of the PV array is 180W, at which point the PV output cannot meet the power demand, operating at the maximum power point A. In the next stage, as the illumination intensity increases, the PV operates on the curve shown in Condition II. At the instant of change, the PV operating point changes from A to A', and the power exceeds the given reference power. The FPPT algorithm switches to CPG mode and tracks to point B. In Condition III, the PV operating point abruptly changes to B' and then tracks towards C. This process passes through the global maximum power point under the current condition. The power rises and falls in a very short time, tracking to the given value of 240W. Finally, in Condition IV, the PV array is unshaded and operates in the same area as the previous condition. The FPPT algorithm quickly tracks to the given power.
[0098] The above embodiments demonstrate that the photovoltaic flexible power point tracking (PPT) method for synchronous frequency regulation in microgrids provided by this invention is feasible and effective. By leveraging the constant voltage characteristics of the photovoltaic MPP high-voltage side to iterate the reference current, it achieves rapid and accurate tracking of any reference power without requiring historical data storage and differential calculations. Even under drastic changes in sunlight, it can stably track the target power, exhibiting strong robustness. This strategy demonstrates significant advantages in power point tracking speed, stability, and engineering practicality.
[0099] Combination Figure 10As shown in the figure, this application provides a photovoltaic flexible power tracking device 800, including a processor 801 and a memory 802. Optionally, the device may further include a communication interface 803 and a bus 804. The processor 801, communication interface 803, and memory 802 can communicate with each other via the bus 804. The communication interface 803 can be used for information transmission. The processor 801 can call logical instructions in the memory 802 to execute the photovoltaic flexible power tracking method of the above embodiment.
[0100] Furthermore, the logic instructions in the aforementioned memory 802 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium.
[0101] The memory 802, as a computer-readable storage medium, can be used to store software programs and computer-executable programs, such as the program instructions / modules corresponding to the methods in the embodiments of this application. The processor 801 executes functional applications and data processing by running the program instructions / modules stored in the memory 802, thereby realizing the photovoltaic flexible power tracking method in the above embodiments.
[0102] The memory 802 may include a program storage area and a data storage area. The program storage area may store the operating system and application programs required for at least one function; the data storage area may store data created based on the use of the terminal device. Furthermore, the memory 802 may include high-speed random access memory and may also include non-volatile memory.
[0103] This application provides a system comprising: a system body and the aforementioned photovoltaic flexible power tracking device 800. The photovoltaic flexible power tracking device 800 is installed on the system body. The installation relationship described herein is not limited to placement within the system, but also includes installation connections with other components of the system, including but not limited to physical connections, electrical connections, or signal transmission connections. Those skilled in the art will understand that the photovoltaic flexible power tracking device 800 can be adapted to feasible system bodies to achieve other feasible embodiments.
[0104] This application provides a computer-readable storage medium storing computer-executable instructions configured to execute the above-described photovoltaic flexible power tracking method.
[0105] The technical solutions of this application embodiment can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes one or more instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in this application embodiment. The aforementioned storage medium can be a non-transitory storage medium, including: USB flash drive, portable hard drive, read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk, and other media capable of storing program code.
[0106] The technical solutions of this application embodiment can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes one or more instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in this application embodiment. The aforementioned storage medium can be a non-transitory storage medium, including: USB flash drive, portable hard drive, read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk, and other media capable of storing program code.
[0107] The foregoing description and accompanying drawings fully illustrate embodiments of this application to enable those skilled in the art to practice them. Other embodiments may include structural, logical, electrical, procedural, and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the order of operation may vary. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. Moreover, the terminology used in this application is for describing embodiments only and is not intended to limit the claims. As used in the description of embodiments and claims, the singular forms “a,” “an,” and “the” are intended to equally include the plural forms unless the context clearly indicates otherwise. Similarly, the term “and / or,” as used herein, means including one or more of the associated listed items and all possible combinations thereof. Additionally, when used in this application, the term "comprise" and its variations "comprises" and / or "comprising" refer to the presence of stated features, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof. Without further limitations, an element defined by the phrase "comprising a..." does not exclude the presence of other identical elements in the process, method, or apparatus that includes said element. In this document, each embodiment may focus on the differences from other embodiments, and similar or identical parts between embodiments can be referred to mutually. For methods, products, etc., of the embodiments claimed, if they correspond to the method section of the embodiments claimed, then the relevant parts can be referred to the description of the method section.
[0108] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments claimed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the embodiments of this application. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.
[0109] The methods and products (including but not limited to devices and equipment) disclosed in the embodiments herein can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For instance, the division of units may be merely a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces, and the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to implement this embodiment according to actual needs. In addition, the functional units in the embodiments of this application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.
[0110] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than that shown in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. In the descriptions corresponding to the flowcharts and block diagrams in the accompanying drawings, the operations or steps corresponding to different blocks may also occur in a different order than disclosed in the description; sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. Each block in a block diagram and / or flowchart, and combinations of blocks in a block diagram and / or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.
Claims
1. A method for rapid photovoltaic flexible power tracking, characterized in that, include: Obtain the current output power of the photovoltaic array; The current search direction for power tracking is determined based on the relationship between the current output power of the photovoltaic array and the reference power. Based on the current search direction, and based on the current output voltage, current output current of the photovoltaic array, and the reference power, the target current is iteratively calculated; the photovoltaic array is controlled to track the target current to perform power tracking.
2. The photovoltaic flexible power tracking method according to claim 1, characterized in that, Based on the relationship between the current output power of the photovoltaic array and the reference power, the current search direction for power tracking is determined, including: If the current output power is lower than the reference power, the search proceeds in the direction of increasing current; if the current output power is higher than the reference power, the search proceeds in the direction of decreasing current.
3. The photovoltaic flexible power tracking method according to claim 2, characterized in that, Based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, taking into account the current output voltage and current of the photovoltaic array and the reference power. Controlling the photovoltaic array to track the target current for power point tracking includes: The target current is calculated iteratively using the dynamic current secant method.
4. The photovoltaic flexible power tracking method according to claim 3, characterized in that, Based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, taking into account the current output voltage and current of the photovoltaic array and the reference power. Controlling the photovoltaic array to track the target current for power point tracking includes: The calculation formula for the dynamic current secant method is as follows: In the formula, I k+1 I is the target current value after iteration. k P is the current output current. ref For reference power, P pv For the current output power, I cal and P cal These are used to calculate the reference point current and power values, respectively.
5. The photovoltaic flexible power tracking method according to claim 4, characterized in that, Based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, taking into account the current output voltage and current of the photovoltaic array and the reference power. Controlling the photovoltaic array to track the target current for power point tracking includes: The permitted operating area for tracking is limited to the high-voltage side of the photovoltaic array at its current maximum power point.
6. The photovoltaic flexible power tracking method according to claim 5, characterized in that, Based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, taking into account the current output voltage and current of the photovoltaic array and the reference power. Controlling the photovoltaic array to track the target current for power point tracking includes: If the error index between the current output power and the reference power is less than the preset power tracking error, then the iteration stops and the current output current is maintained.
7. The photovoltaic flexible power tracking method according to claim 6, characterized in that, Based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, taking into account the current output voltage and current of the photovoltaic array and the reference power. Controlling the photovoltaic array to track the target current for power point tracking includes: The error index is calculated using the following formula: In the formula, e k Let ε be the error index, and let ε be the preset power tracking error.
8. The photovoltaic flexible power tracking method according to claim 7, characterized in that, Based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, taking into account the current output voltage and current of the photovoltaic array and the reference power. Controlling the photovoltaic array to track the target current for power point tracking includes: If the power is detected to be insufficient to meet the preset requirements during power point tracking, the system will switch to maximum power point tracking mode.
9. The photovoltaic flexible power tracking method according to claim 8, characterized in that, Based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, taking into account the current output voltage and current of the photovoltaic array and the reference power. Controlling the photovoltaic array to track the target current for power point tracking includes: If the target current obtained by iterative calculation is greater than the current maximum power point current of the photovoltaic array, and the corresponding current output power is still less than the reference power, then the photovoltaic array is controlled to switch to maximum power point tracking mode.
10. The photovoltaic flexible power tracking method according to claim 9, characterized in that, Based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, taking into account the current output voltage and current of the photovoltaic array and the reference power. Controlling the photovoltaic array to track the target current for power point tracking includes: When switched to maximum power point tracking mode, a local maximum power point search is continuously performed to maintain the maximum power output of the photovoltaic array.
11. The photovoltaic flexible power tracking method according to claim 10, characterized in that, Based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, taking into account the current output voltage and current of the photovoltaic array and the reference power. Controlling the photovoltaic array to track the target current for power point tracking includes: The maximum value of the target current is set to the recorded global maximum power point current of the photovoltaic array.
12. The photovoltaic flexible power tracking method according to claim 11, characterized in that, Based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, taking into account the current output voltage and current of the photovoltaic array and the reference power. Controlling the photovoltaic array to track the target current for power point tracking includes: When the reference power undergoes a step change, the iterative calculation is repeated.
13. The photovoltaic flexible power tracking method according to claim 12, characterized in that, Based on the current search direction, the target current is iteratively calculated using the dynamic current secant method, taking into account the current output voltage and current of the photovoltaic array and the reference power. Controlling the photovoltaic array to track the target current for power point tracking includes: The reference power is dynamically issued by either the microgrid group's central controller or the local controller based on the system's frequency regulation requirements.
14. A photovoltaic flexible power tracking device, comprising a processor and a memory storing program instructions, characterized in that, The processor is configured to execute the photovoltaic flexible power tracking method as described in any one of claims 1 to 13 when running the program instructions.
15. A system, characterized in that, include: System body; as well as, The photovoltaic flexible power tracking device as described in claim 14 is installed on the system body.
16. A computer-readable storage medium storing program instructions, characterized in that, When the program instructions are executed, they cause the computer to perform the photovoltaic flexible power tracking method as described in any one of claims 1 to 13.