Photovoltaic Voltage Control Method and System Based on Adaptive Dichotomy

Abstract

The present invention discloses a photovoltaic voltage control method and system based on an adaptive dichotomy method. The photovoltaic voltage control method of the present invention determines the adaptive step adjustment coefficient of the dichotomy method according to the voltage error, calculates the power adjustment amount of the photovoltaic inverter, and gradually approaches the output voltage to the target voltage by dynamically adjusting the output power of the photovoltaic. Moreover, compared with the traditional dichotomy method with a fixed step, the adaptive dichotomy method can flexibly change the step according to the real-time voltage error, can not only quickly respond under the condition of large voltage fluctuations, but also finely adjust when approaching the target voltage, minimizing the risk of voltage over-limit or under-voltage to the greatest extent, improving the stability of the system, and realizing the precise control of the photovoltaic output voltage.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic voltage control, and in particular, to a photovoltaic voltage control method and system, an electronic device, and a computer-readable storage medium based on an adaptive dichotomy method. Background Art

[0002] With the continuous growth of power demand and the decreasing supply capacity of traditional energy sources (non-renewable energy sources decreasing), the rapid development of new energy systems has become an effective solution to meet current multi-faceted demands. Among them, photovoltaic power generation, as an important part of the clean energy field, provides key support for the global energy structure transformation by efficiently converting light energy into electrical energy. To adapt to such a development trend, the traditional power grid has evolved from a single "power grid - load" structure to a "source - grid - load - storage" four-element structure, with increasing system complexity and higher requirements for the reliability and efficiency of power grid management. In a photovoltaic system, an inverter is a core component, and its main task is to convert the direct current generated by photovoltaic modules into alternating current. However, due to the dynamic changes in environmental factors such as light intensity and temperature, the stability and regulation ability of the output voltage of the photovoltaic system face severe challenges. Especially when the photovoltaic modules are shaded or the light intensity fluctuates violently, the voltage may fluctuate significantly and even exceed the safe operating range of the system, that is, the voltage may be over-limited or under-voltage. Such voltage anomalies directly threaten the safe operation of the photovoltaic system and the power grid.

[0003] Currently, a photovoltaic inverter cannot directly regulate the output voltage but indirectly affects the voltage by adjusting the power. Existing technologies usually use the MPPT (Maximum Power Point Tracking) algorithm to adjust the output power of the photovoltaic system. The MPPT algorithm realizes the efficient tracking of the maximum power point under dynamic changes in environmental parameters by continuously monitoring the non-linear I-V characteristics of the photovoltaic array and dynamically adjusting the load impedance, combined with intelligent control algorithms (such as the perturbation observation method, the conductance increment method, or particle swarm optimization, etc.). However, the goal of the MPPT algorithm is to ensure the normal output of the inverter power under abnormal conditions and has no direct effect on voltage regulation. When the photovoltaic output power is normal, the output voltage of the photovoltaic system may still be over-limited or under-voltage, and the impact of too high or too low voltage on the system is more direct and serious. For example, it may damage electrical equipment, trigger voltage collapse, or even cause large-scale power outages. The power grid's requirement for voltage stability is significantly higher than that for power stability. Summary of the Invention

[0004] The present invention provides a photovoltaic voltage control method and system, an electronic device, and a computer-readable storage medium based on an adaptive dichotomy method, which can respond quickly under large voltage fluctuations, can also finely adjust when approaching the target voltage, minimize the risk of voltage over-limit or under-voltage, improve the stability of the system, and achieve precise control of the photovoltaic output voltage.

[0005] According to one aspect of the present invention, there is provided a photovoltaic voltage control method based on an adaptive dichotomy method, including the following:

[0006] Collect the output voltage of the photovoltaic inverter and calculate the voltage error, where the voltage error refers to the difference between the target voltage and the current voltage;

[0007] Determine the adaptive step size adjustment coefficient of the dichotomy method based on the voltage error and calculate the power adjustment amount of the photovoltaic inverter;

[0008] Adjust the output power of the photovoltaic inverter based on the calculated power adjustment amount.

[0009] Further, the adaptive step size adjustment coefficient of the dichotomy method is determined based on the following formula:

[0010] ;

[0011] Wherein, k represents the adaptive step size adjustment coefficient, k max and k min represent the maximum step size adjustment coefficient and the minimum step size adjustment coefficient respectively, ΔV ( t ) represents t the voltage error at time ΔV 1 and ΔV 2 represent preset voltage error thresholds, and ΔV 1 > ΔV 2, k 1 and k 2 are constants.

[0012] Further, the power adjustment amount of the photovoltaic inverter is calculated based on the following formula:

[0013] ;

[0014] Wherein, k represents the adaptive step size adjustment coefficient, ΔV ( t ) represents t the voltage error at time ΔP current ( t ) representst The power adjustment amount at a moment.

[0015] Further, after calculating the voltage error, if the voltage error is within a preset safe range, no voltage regulation is performed; if the voltage error is not within the preset safe range, voltage regulation is performed.

[0016] Further, after calculating the power adjustment amount of the photovoltaic inverter, the following is also included:

[0017] Cyclically sample the output voltage of the photovoltaic inverter and adopt the oldest discard mechanism to obtain a voltage sampling sequence. Determine a correction coefficient according to the latest voltage change amount and the latest voltage error in the voltage sampling sequence, and use the correction coefficient to correct the power adjustment amount of the photovoltaic inverter.

[0018] Further, when the latest voltage change amount is less than the first change amount threshold, if the latest voltage error is less than zero, the correction coefficient is set to w 21 ; if the latest voltage error is greater than zero, the correction coefficient is set to w 22 , where 0 < w 21 < 1, w 22 > 1, and the first change amount threshold is less than zero;

[0019] When the latest voltage change amount is greater than the second change amount threshold, if the latest voltage error is less than zero, the correction coefficient is set to w 11 ; if the latest voltage error is greater than zero, the correction coefficient is set to w 12 , where w 11 > 1, 0 < w 12 < 1, and the second change amount threshold is greater than zero;

[0020] When the latest voltage change amount is greater than or equal to the first change amount threshold and less than or equal to the second change amount threshold, regardless of whether the latest voltage error is less than zero or greater than zero, the correction coefficient is set to 1.

[0021] Further, after calculating the power adjustment amount of the photovoltaic inverter, the following is also included:

[0022] Based on voltage feedback and power feedback, perform dual-feedback PID regulation to calculate the feedback adjustment amount of the photovoltaic inverter.

[0023] In addition, the present invention also provides a photovoltaic voltage control system based on an adaptive dichotomy method, including:

[0024] A voltage error calculation module, which is used to collect the output voltage of a photovoltaic inverter and calculate the voltage error, where the voltage error refers to the difference between the target voltage and the current voltage;

[0025] A power adjustment amount calculation module, which is used to determine the adaptive step size adjustment coefficient of the dichotomy method based on the voltage error and calculate the power adjustment amount of the photovoltaic inverter;

[0026] A photovoltaic output power control module, which is used to adjust the output power of the photovoltaic inverter based on the calculated power adjustment amount.

[0027] In addition, the present invention also provides an electronic device, including a processor and a memory. A computer program is stored in the memory, and the processor is used to execute the steps of the method described above by calling the computer program stored in the memory.

[0028] In addition, the present invention also provides a computer-readable storage medium, which is used to store a computer program for photovoltaic voltage control based on the adaptive dichotomy method. When the computer program runs on a computer, it executes the steps of the method described above.

[0029] The present invention has the following beneficial effects:

[0030] The photovoltaic voltage control method based on the adaptive dichotomy method of the present invention determines the adaptive step size adjustment coefficient of the dichotomy method according to the voltage error, calculates the power adjustment amount of the photovoltaic inverter, and makes the output voltage gradually approach the target voltage by dynamically adjusting the output power of the photovoltaic. Compared with the traditional dichotomy method with a fixed step size, the adaptive dichotomy method can flexibly change the step size according to the real-time voltage error, can not only respond quickly when the voltage fluctuates greatly, but also finely adjust when approaching the target voltage, minimizing the risk of voltage over-limit or under-voltage, improving the stability of the system, and realizing the precise control of the photovoltaic output voltage.

[0031] In addition, the photovoltaic voltage control system based on the adaptive dichotomy method of the present invention also has the above advantages.

[0032] In addition to the purposes, features and advantages described above, the present invention has other purposes, features and advantages. The present invention will be further described in detail below with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0034] Figure 1It is a schematic flowchart of the photovoltaic voltage control method based on the adaptive bisection method in the preferred embodiment of the present application;

[0035] Figure 2 It is another schematic flowchart of the photovoltaic voltage control method based on the adaptive bisection method in the preferred embodiment of the present application;

[0036] Figure 3 It is yet another schematic flowchart of the photovoltaic voltage control method based on the adaptive bisection method in the preferred embodiment of the present application;

[0037] Figure 4 It is a schematic diagram of the module structure of the photovoltaic voltage control system based on the adaptive bisection method in another embodiment of the present application. Detailed implementation manners

[0038] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0039] Refer to Figure 1 , the preferred embodiment of the present application provides a photovoltaic voltage control method based on the adaptive bisection method, including the following content:

[0040] Step S1: Collect the output voltage of the photovoltaic inverter and calculate the voltage error, where the voltage error refers to the difference between the target voltage and the current voltage;

[0041] Step S2: Determine the adaptive step size adjustment coefficient of the bisection method based on the voltage error and calculate the power adjustment amount of the photovoltaic inverter;

[0042] Step S3: Adjust the output power of the photovoltaic inverter based on the calculated power adjustment amount.

[0043] It can be understood that the photovoltaic voltage control method based on the adaptive bisection method in this embodiment determines the adaptive step size adjustment coefficient of the bisection method according to the voltage error, calculates the power adjustment amount of the photovoltaic inverter, and makes the output voltage gradually approach the target voltage by dynamically adjusting the output power of the photovoltaic. Moreover, compared with the traditional bisection method with a fixed step size, the adaptive bisection method can flexibly change the step size according to the real-time voltage error, can quickly respond in the case of large voltage fluctuations, and can finely adjust when approaching the target voltage, minimizing the risk of voltage over-limit or under-voltage to the greatest extent, improving the stability of the system, and realizing the precise control of the photovoltaic output voltage.

[0044] Among them, in the step S1, the output voltage of the photovoltaic inverter is monitored in real time through a voltage sensor, and the voltage error is calculated. The voltage error refers to the difference between the target voltage and the current voltage, and can be expressed as: ΔV (t ) = V target - V ( t ),wherein, V target represents the target voltage, V ( t ) represents the output voltage of the PV inverter at time t, ΔV ( t ) represents the voltage error at time t.

[0045] In addition, in the step S2, according to the real-time voltage error calculated in step S1, the power adjustment direction of the PV inverter can be determined. For example, when the voltage error is negative, it means that voltage over-limit may occur, and at this time, the output power of the PV inverter needs to be reduced. When the voltage error is positive, it means that voltage under-voltage may occur, and at this time, the output power of the PV inverter needs to be increased. In addition, the relationship between the output power and the output voltage of the PV inverter is: , wherein, P ( t ) represents t the output power of the PV inverter at time a , b , c are constants, and it can be obtained that: , wherein, ΔP current ( t ) represents t the power adjustment amount at time Δ V ( t ) represents t the voltage error at time ΔV ( t ) = ΔV ( t ) / 2, that is, the bisection method is used for adjustment. After further simplification, it can be obtained that: , wherein, k represents the adaptive step-size adjustment coefficient. The present invention designs a piecewise function according to the value of ΔV ( t ) to achieve the adaptive adjustment of the value of k . Specifically, the adaptive step-size adjustment coefficient of the bisection method is determined based on the following formula:

[0046] ;

[0047] wherein, k represents the adaptive step-size adjustment coefficient, k max and k minrespectively represent the maximum step adjustment coefficient and the minimum step adjustment coefficient, k max > k min , ΔV ( t ) represents t the voltage error at the moment, ΔV 1 and ΔV 2 represent the preset voltage error thresholds, and ΔV 1 > ΔV 2, k 1 and k 2 are constants determined according to the adjustment accuracy and the tolerable range. It can be seen from the above formula that when , it indicates that the amplitude of overvoltage or undervoltage is small, and slow adjustment is required. Therefore, k the minimum step adjustment coefficient is adopted to achieve fine adjustment; while when , it indicates that the amplitude of overvoltage or undervoltage is large, and fast adjustment is required. Therefore, k the maximum step adjustment coefficient is adopted to achieve fast response; while when , it indicates that the amplitude of overvoltage or undervoltage is moderate, then the average differential adjustment method is adopted. By constructing a linear change process, the larger the real-time voltage error is, the k larger the value of k is, and the smaller the real-time voltage error is, the

[0048] It can be understood that the present invention adaptively and dynamically adjusts the step adjustment coefficient of the dichotomy method through the real-time voltage error, and continuously optimizes the power adjustment step to achieve precise control of the voltage. Compared with the traditional dichotomy method with a fixed step, the step can be flexibly changed according to the real-time voltage error, which can not only quickly respond under large voltage fluctuations, but also finely adjust when approaching the target voltage, minimizing the risk of overvoltage or undervoltage and improving the stability of the system.

[0049] In addition, in step S3, after calculating the power adjustment amount ΔP current ( t ) of the photovoltaic inverter in step S2, the target output power of the photovoltaic inverter at the next moment can be calculated as: P adjust ( t + 1) = P current ( t ) + Δ P current ( t ), whereP current ( t ) represents t the output power of the photovoltaic inverter at a certain moment, P adjust ( t + 1) represents t the target output power of the photovoltaic inverter at the moment of + 1.

[0050] In addition, the method of indirectly adjusting the output voltage by adjusting the output power of the photovoltaic inverter has the defects of easy overshoot and delay. The reasons are as follows: 1) The output voltage of the photovoltaic inverter changes in real time, so the voltage error value also changes in real time. If it is determined that the voltage needs to be increased according to the voltage error value, and if the change trend of the voltage itself is also increasing, it is very easy to cause overshoot; 2) When the current voltage error is large, it is difficult for the adaptive dichotomy method to quickly adjust the output voltage to the target value, and the delay is relatively large; 3) When the voltage error is small, if the adjustment is still repeated, it will cause voltage overshoot, voltage instability or cause a larger voltage error leading to overshoot. Although higher-order algorithms can be used to solve the defects of overshoot and delay, the computational complexity of higher-order algorithms is large, and it is difficult to meet the lightweight computational requirements.

[0051] Therefore, optionally, after calculating the voltage error ΔV ( t ), if the voltage error ΔV ( t ) is within the preset safety range α , no voltage regulation is performed. If the voltage error ΔV ( t ) is not within the preset safety range α , voltage regulation is performed, which can prevent the problem of enhanced voltage fluctuation caused by repeated adjustment in the case of small voltage error and effectively solve the overshoot problem. Among them, α can be set according to actual needs. For example, it can be set as α = V target ×4.5%, that is, when the deviation between the current output voltage and the target voltage is within the safety range of 4.5%, no voltage regulation is performed, and voltage regulation is only performed after exceeding the safety range of 4.5%.

[0052] It can be understood that after calculating the real-time voltage error, the present invention compares the voltage error with the preset safety range, and voltage regulation is only performed when the preset safety range is exceeded, preventing the problem of enhanced voltage fluctuation caused by repeated adjustment in the case of small voltage error and effectively solving the overshoot problem.

[0053] In addition, as Figure 2As shown, after calculating the power adjustment amount of the PV inverter, the PV voltage control method based on the adaptive dichotomy method further includes the following:

[0054] Step S21: Cyclically sample the output voltage of the PV inverter and adopt the oldest elimination mechanism to obtain a voltage sampling sequence. Determine the correction coefficient according to the latest voltage change amount and the latest voltage error in the voltage sampling sequence, and use the correction coefficient to correct the power adjustment amount of the PV inverter.

[0055] Specifically, usually the sampling period of the voltage is 20 ms. To improve resource utilization, the present invention samples the output voltage value of the PV inverter with a period of 100 ms to obtain a voltage sampling sequence V n , where n The maximum is 1000, so a cycle totals 100 s, and the oldest elimination mechanism is adopted, that is, after storing 1000 data, the earliest data is eliminated and the latest data is added. Then, calculate the latest voltage change amount Δ V n -1], and the calculation formula is: Δ V n -1]= V n - V n -1], and calculate the latest voltage error value Δ V ( n ), and the calculation formula is: Δ V ( n )= V target - V n , and determine the correction coefficient according to Δ V n -1] and Δ V ( n ), and use the correction coefficient to correct the power adjustment amount of the PV inverter.

[0056] Among them, when the latest voltage change amount Δ V n -1] is less than the first change amount threshold β 1, if the latest voltage error Δ V ( n ) is less than zero, then the correction coefficient w is set to w 21 , if the latest voltage error Δ V ( n ) is greater than zero, then the correction coefficient w is set to​​​​​​​​w 22 , where 0 < w 21 < 1, w 22 > 1, the first change amount threshold β 1 is less than zero; when the latest voltage change amount Δ V n -1] is greater than the second change amount threshold β 2, if the latest voltage error Δ V ( n ) is less than zero, then the correction coefficient w is set to w 11 , if the latest voltage error Δ V ( n ) is greater than zero, then the correction coefficient w is set to w 12 , where w 11 > 1, 0 < w 12 < 1, the second change amount threshold β 2 is greater than zero; when the latest voltage change amount Δ V n -1] is greater than or equal to the first change amount threshold β 1 and less than or equal to the second change amount threshold β 2, regardless of whether the latest voltage error Δ V ( n ) is less than zero or greater than zero, the correction coefficient w is set to 1. Where β 1, β 2, w 21 , w 22 , w 11 , w 12 The values of can be set according to actual needs. For example, in the power grid, the undervoltage determination threshold is 78% × V target , the overlimit determination threshold is 120% × V target , so for undervoltage and overlimit, the voltage tolerance is 22% and 20% respectively, and the ratio is 11:10. Then β 1 can take the value of - V target × 0.66%, β 2 can take the value of V target × 0.6%, w ​​11 The value is 3.6, w 12 The value is 0.8, w 21 The value is 0.88, w 22 The value is 3.27. In addition, the corrected power adjustment amount is: .

[0057] It can be understood that the present invention determines the correction coefficient according to the latest voltage change amount and the latest voltage error. When the voltage change amount shows an increasing trend of the voltage, that is , if , that is, there is overvoltage. At this time, a larger correction coefficient is adopted to achieve fast reduction, so that the output voltage quickly approaches the target value. If , that is, there is undervoltage. At this time, a smaller correction coefficient is adopted to achieve slow increase and prevent overshoot problems; when the voltage change amount shows a decreasing trend of the voltage, that is , if , that is, there is overvoltage. At this time, a decreasing correction coefficient is adopted to achieve slow reduction and prevent overshoot problems. If , that is, there is undervoltage. At this time, a larger correction coefficient is adopted to achieve fast increase, so that the output voltage quickly approaches the target value; when the voltage change amount shows a stable change trend, that is , regardless of or , the correction coefficient is 1, that is, no correction is performed. The present invention comprehensively corrects the power adjustment range of the photovoltaic inverter according to the real-time voltage change amount and voltage error, which can effectively solve the problems of overshoot and delay, and occupies less computing resources, and can well meet the lightweight computing requirements.

[0058] In addition, as Figure 3 shown, after calculating the power adjustment amount of the photovoltaic inverter, the photovoltaic voltage control method based on the adaptive dichotomy method further includes the following content:

[0059] Step S22: Perform dual-feedback PID adjustment based on voltage feedback and power feedback, and calculate the feedback adjustment amount of the photovoltaic inverter.

[0060] Specifically, the present invention also performs dual-feedback PID adjustment based on voltage feedback and power feedback to optimize the power output while ensuring voltage stability. Among them, the PID adjustment based on voltage feedback can be expressed as: , where k p , k i , k drespectively represent the proportional coefficient, integral coefficient, and differential coefficient, ΔV ( t ) represents the voltage error, ΔV ( t ) PID represents the voltage error calculated based on PID feedback regulation. Since the inverter cannot directly regulate the output voltage, the following formula also needs to be combined: to obtain through conversion: , represents the power regulation amount calculated based on voltage feedback for PID calculation.

[0061] In addition, the PID regulation based on power feedback can be expressed as: , where k p1 , k i1 , k d1 respectively represent the proportional coefficient, integral coefficient, and differential coefficient, represents the power regulation amount calculated based on power feedback for PID calculation.

[0062] Therefore, the feedback regulation amount of the photovoltaic inverter is: , where represents the power feedback regulation amount calculated based on dual-feedback PID regulation. In addition, the target output power of the photovoltaic inverter at the next moment finally calculated is: P adjust ( t + 1) = P current ( t ) + ΔP current ( t ) + ΔP PID ( t ).

[0063] It can be understood that the present invention performs dual-feedback PID regulation based on voltage feedback and power feedback, adjusts the voltage error in real time based on voltage feedback to ensure voltage stability, and adjusts the output power in real time based on power feedback to achieve output optimization, not only improving the power regulation accuracy and voltage control accuracy, but also enhancing the robustness of the algorithm.

[0064] In addition, the inventors of the present invention also conducted experimental comparisons between the photovoltaic voltage control method of the present invention and the existing MPPT algorithm. The experimental comparison results are shown in the following table:

[0065]

[0066] It can be seen that compared with the existing MPPT algorithms, the photovoltaic voltage control algorithm of the present invention has improvements in terms of response speed, regulation accuracy, and energy efficiency. Compared with the traditional fixed-step dichotomy method, it also has improvements in response speed and regulation accuracy.

[0067] In addition, as Figure 4 shown, another embodiment of the present invention further provides a photovoltaic voltage control system based on the adaptive dichotomy method, preferably adopting the photovoltaic voltage control method based on the adaptive dichotomy method as described above, including:

[0068] A voltage error calculation module, configured to collect the output voltage of the photovoltaic inverter and calculate the voltage error, where the voltage error refers to the difference between the target voltage and the current voltage;

[0069] A power adjustment amount calculation module, configured to determine the adaptive step adjustment coefficient of the dichotomy method based on the voltage error and calculate the power adjustment amount of the photovoltaic inverter;

[0070] A photovoltaic output power regulation module, configured to regulate the output power of the photovoltaic inverter based on the calculated power adjustment amount.

[0071] It can be understood that the photovoltaic voltage control system based on the adaptive dichotomy method in this embodiment determines the adaptive step adjustment coefficient of the dichotomy method according to the voltage error and calculates the power adjustment amount of the photovoltaic inverter. By dynamically adjusting the output power of the photovoltaic, the output voltage gradually approaches the target voltage. And compared with the traditional fixed-step dichotomy method, the adaptive dichotomy method can flexibly change the step according to the real-time voltage error, can quickly respond when the voltage fluctuates greatly, and can finely adjust when approaching the target voltage, minimizing the risk of voltage over-limit or under-voltage, improving the stability of the system, and achieving precise control of the photovoltaic output voltage.

[0072] In addition, the photovoltaic voltage control system based on the adaptive dichotomy method further includes:

[0073] A power adjustment amount correction module, configured to perform cyclic period sampling on the output voltage of the photovoltaic inverter and adopt the oldest elimination mechanism to obtain a voltage sampling sequence, determine a correction coefficient according to the latest voltage change amount and the latest voltage error in the voltage sampling sequence, and use the correction coefficient to correct the power adjustment amount of the photovoltaic inverter.

[0074] In addition, the photovoltaic voltage control system based on the adaptive dichotomy method further includes:

[0075] A dual-feedback PID regulation module, configured to perform dual-feedback PID regulation based on voltage feedback and power feedback and calculate the feedback regulation amount of the photovoltaic inverter.

[0076] In addition, another embodiment of the present invention further provides an electronic device, including a processor and a memory. A computer program is stored in the memory. The processor is configured to execute the steps of the method as described above by invoking the computer program stored in the memory.

[0077] In addition, another embodiment of the present invention further provides a computer-readable storage medium for storing a computer program for photovoltaic voltage control based on the adaptive dichotomy method. The computer program, when running on a computer, executes the steps of the method as described above.

[0078] The forms of common computer-readable storage media generally include: floppy disks, flexible disks, hard disks, magnetic tapes, any other magnetic media, CD-ROMs, any other optical media, punch cards, paper tapes, any other physical media with a pattern of holes, random access memories (RAMs), programmable read-only memories (PROMs), erasable programmable read-only memories (EPROMs), flash erasable programmable read-only memories (FLASH-EPROMs), any other memory chips or cartridges, or any other media readable by a computer. Instructions can further be transmitted or received by a transmission medium. The term transmission medium can include any tangible or intangible medium that can be used to store, encode, or carry instructions for execution by a machine, and includes digital or analog communication signals or the intangible medium that facilitates the communication of the above instructions. The transmission medium includes coaxial cables, copper wires, and optical fibers, which include the wires of a bus for transmitting a computer data signal.

[0079] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) that contain computer-usable program code. The solutions in the embodiments of the present application can be implemented in various computer languages. For example, object-oriented programming languages such as Java and interpreted scripting languages such as JavaScript.

[0080] This application is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or means for implementing the functions specified in one block or multiple blocks.

[0081] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means that implement the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or means for implementing the functions specified in one block or multiple blocks.

[0082] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one flow Figure 1 one flow or multiple flows and / or blocks Figure 1 or means for implementing the functions specified in one block or multiple blocks.

[0083] Although the preferred embodiments of the present application have been described, those skilled in the art can make additional changes and modifications once they know the basic creative concepts. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0084] Obviously, those skilled in the art can make various changes and variations to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application is also intended to include these modifications and variations.

[0085] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A photovoltaic voltage control method based on the adaptive bisection method, characterized in that, It includes the following: Collect the output voltage of the photovoltaic inverter and calculate the voltage error, where the voltage error refers to the difference between the target voltage and the current voltage; Determine the adaptive step size adjustment coefficient of the bisection method based on the voltage error and calculate the power adjustment amount of the photovoltaic inverter; Adjust the output power of the photovoltaic inverter based on the calculated power adjustment amount; After calculating the voltage error, if the voltage error is within the preset safety range, no voltage regulation is performed. Voltage regulation is only performed if the voltage error is not within the preset safety range; After calculating the power adjustment amount of the photovoltaic inverter, it further includes the following: Perform cyclic period sampling on the output voltage of the photovoltaic inverter and adopt the oldest elimination mechanism to obtain a voltage sampling sequence. Determine the correction coefficient based on the latest voltage change amount and the latest voltage error in the voltage sampling sequence, and use the correction coefficient to correct the power adjustment amount of the photovoltaic inverter; When the latest voltage change amount is less than the first change amount threshold, if the latest voltage error is less than zero, set the correction coefficient to w 21 , if the latest voltage error is greater than zero, set the correction coefficient to w 22 , where 0 < w 21 < 1, w 22 > 1, and the first change amount threshold is less than zero; When the latest voltage change amount is greater than the second change amount threshold, if the latest voltage error is less than zero, set the correction coefficient to w 11 , if the latest voltage error is greater than zero, set the correction coefficient to w 12 , where w 11 > 1, 0 < w 12 < 1, and the second change amount threshold is greater than zero; When the latest voltage change amount is greater than or equal to the first change amount threshold and less than or equal to the second change amount threshold, regardless of whether the latest voltage error is less than zero or greater than zero, the correction coefficient is set to 1.

2. The photovoltaic voltage control method based on the adaptive dichotomy according to claim 1, wherein, Determine the adaptive step size adjustment coefficient of the bisection method based on the following formula: Among them, k represents the adaptive step size adjustment coefficient, k max and k min respectively represent the maximum step size adjustment coefficient and the minimum step size adjustment coefficient, ΔV(t) represents the voltage error at time t, ΔV1 and ΔV2 represent the preset voltage error thresholds, and ΔV1 > ΔV2, k1 and k2 are constants.

3. The photovoltaic voltage control method based on the adaptive dichotomy according to claim 1, characterized in that Calculate the power adjustment amount of the photovoltaic inverter based on the following formula: ΔP current (t) = k·ΔV(t) where k represents the adaptive step size adjustment coefficient, ΔV(t) represents the voltage error at time t, and ΔP current (t) represents the power adjustment amount at time t.

4. The photovoltaic voltage control method based on the adaptive dichotomy according to claim 1, wherein, After calculating the power adjustment amount of the photovoltaic inverter, it further includes the following: Perform dual feedback PID regulation based on voltage feedback and power feedback and calculate the feedback adjustment amount of the photovoltaic inverter.

5. A photovoltaic voltage control system based on the adaptive dichotomy method, which adopts the photovoltaic voltage control method based on the adaptive dichotomy method as described in any one of claims 1 to 4, characterized in that, It includes: A voltage error calculation module for collecting the output voltage of the photovoltaic inverter and calculating the voltage error, where the voltage error refers to the difference between the target voltage and the current voltage; A power adjustment amount calculation module for determining the adaptive step size adjustment coefficient of the bisection method based on the voltage error and calculating the power adjustment amount of the photovoltaic inverter; A photovoltaic output power regulation module for adjusting the output power of the photovoltaic inverter based on the calculated power adjustment amount.

6. An electronic device, characterized in that, It includes a processor and a memory. The memory stores a computer program. The processor is used to execute the steps of the method according to any one of claims 1 to 4 by calling the computer program stored in the memory.

7. A computer-readable storage medium for storing a computer program for photovoltaic voltage control based on an adaptive bisection method, characterized in that, When the computer program runs on a computer, it executes the steps of the method according to any one of claims 1 to 4.

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