A voltage-reactive power control method, device and medium based on centralized optimization

Abstract

The present application is a voltage-reactive control method, device and medium based on centralized optimization, which belongs to the field of power system. In view of the unreasonable problem of existing optimization methods, the present application provides a voltage-reactive multi-mode optimization control method based on centralized optimization, including: detecting and identifying the instructions issued by the upper layer optimization; setting the voltage adjustment interval, and setting the local voltage-reactive curve according to the instruction result; outputting the reactive power reference value of the inverter according to the local voltage-reactive curve; regulating the reactive power of the inverter according to the reactive power reference value of the inverter, and adjusting the grid connection point voltage until it is stable; judging whether the stable grid connection point voltage is within the voltage adjustment interval; periodically detecting the grid connection point voltage value, and judging whether the detected grid connection point voltage fluctuates greatly. The present invention improves the compatibility of the inverter with the upper layer optimization, effectively suppresses the voltage fluctuation and over-limit of the power grid, and improves the voltage support capacity of the inverter, the quality of the power grid voltage, and the reliability of the power grid operation.

Description

Technical Field

[0001] The present invention belongs to the field of electric power systems, and in particular relates to a voltage-reactive power control method, device and medium based on centralized optimization. Background Art

[0002] With the large number of distributed photovoltaic systems being connected to the distribution network, the penetration rate of photovoltaics has increased, and the voltage at the photovoltaic grid connection point has risen, resulting in serious voltage over-limit problems in the distribution network, and even more serious over-limit problems at the end of the distribution network line, which affects the power quality and operational reliability of the distribution network and restricts the further development of distributed photovoltaics. The photovoltaic inverter itself can absorb / send reactive power to regulate the grid voltage. It is necessary to make full use of the reactive power of the inverter to suppress overvoltage problems, improve the voltage support capacity of distributed photovoltaics and the power quality of the distribution network, and promote the further development of photovoltaic systems. In order to alleviate the voltage fluctuation and overvoltage problems caused by photovoltaic output, voltage-reactive power, constant power factor, voltage-active power and other voltage support functions have been widely used. Among them, voltage-reactive power control measures the voltage at the photovoltaic grid connection point, calculates the reactive power reference value that the inverter needs to absorb / send according to the voltage-reactive power curve, and dynamically adjusts the output of reactive power, which can effectively realize the regulation of the voltage at the grid connection point. However, most of the installed commercial photovoltaic inverters operate in constant reactive power or unity power factor mode, and need to be connected to an external controller to achieve voltage-reactive power control. Through the communication and coordination between the inverter / external controller and the central controller, centralized-local voltage two-stage control can be achieved: the centralized control (central controller) optimizes the reactive power of the inverter or the voltage-reactive control curve in the external controller in combination with global information, and the local (external controller + inverter) controls the grid connection point voltage according to the measured data in accordance with the optimization instructions issued by the centralized control. In actual projects, the conditions for centralized optimization are complex. Usually, the optimization result is the local control reactive power reference value or voltage-reactive curve within the optimization time period, and then the optimization result is sent to the local control, which is regulated according to the result of centralized optimization. If the optimization result is the reactive power reference value of the local control, the local control cannot be directly converted into voltage-reactive control, and the inverter output can only achieve constant reactive power output, and cannot be regulated according to the operation changes of the distribution network; if the optimization result is the voltage-reactive curve of the local control, the local control can calculate the reactive power reference value for the inverter according to the optimized voltage-reactive curve, but the voltage-reactive curve is fixed during the optimization time period, and does not have the ability to adaptively adjust the curve as the operation status of the distribution network changes. Considering the communication delay between the central controller, external controller and inverter and the complexity of global optimization, the centralized optimization results are often optimized for a long time scale. On a short time scale, the inverter / external controller still needs to adjust the voltage-reactive power control according to the optimization results and local operating conditions to improve the reliability of local regulation.

[0003] Through the above analysis, the problems and defects of the existing technology are: centralized optimization is complex and has high communication requirements, and the external control / inverter needs to match the centralized optimization and local control; the local control does not have adaptive adjustment capabilities and only relies on the initial setting curve for regulation. Summary of the invention

[0004] In view of the problem that existing optimization methods are unreasonable, the present invention provides a voltage-reactive power control method, device and medium based on centralized optimization, which can realize diverse adaptation of local voltage-reactive power control and upper-level centralized optimization instructions, and adaptive regulation of inverter local control.

[0005] The present application provides a voltage-reactive power multi-mode optimization control method based on centralized optimization, comprising:

[0006] S1, detects and identifies the instructions sent by the upper layer optimization;

[0007] S2, setting the voltage regulation interval and setting the local voltage-reactive power curve according to the recognized command result;

[0008] S3, outputting the reactive power reference value of the inverter according to the set local voltage-reactive power curve;

[0009] S4, regulating the reactive power of the inverter according to the reactive power reference value of the inverter, and then adjusting the grid connection point voltage until it is stable; judging whether the stable grid connection point voltage is within the set voltage adjustment range;

[0010] If yes, continue to regulate according to the set local voltage-reactive power curve;

[0011] If not, a virtual voltage difference is set, and the voltage at the grid connection point before adjustment is adjusted by adding or subtracting the virtual voltage difference; this is repeated several times until the voltage at the grid connection point reaches the set voltage adjustment range, and the accumulated voltage difference is obtained;

[0012] S5, periodically detect the voltage value of the grid connection point. When it is determined that the voltage fluctuation of the grid connection point is large, that is, when a large change in the operation of the distribution network is detected, the accumulated voltage difference is set to zero, and then return to step S2, and then adjust according to the set voltage-reactive power curve.

[0013] The upper layer optimization instructions can be processed centrally according to the received centralized optimization instructions to form a voltage reactive power curve. Adaptive regulation can be achieved by judging whether the grid connection point voltage is within the set voltage regulation range.

[0014] Furthermore, the instructions sent by the upper layer optimization include the voltage-reactive power curve slope, voltage-reactive power curve, grid connection point reference voltage U0 and reactive power reference value Q0 of the inverter in a time period or moment.

[0015] Further, if the upper optimization result is the grid-connected point reference voltage U0 and reactive power reference value Q0 of the inverter in a time period or moment, the local voltage-reactive power curve is set according to the grid-connected point reference voltage U0 and reactive power reference value Q0;

[0016] If the upper optimization result is the slope of the voltage-reactive curve, the upper and lower boundaries of the local voltage-reactive curve are set based on the current reactive remaining capacity of the inverter, and the reference voltage of the local voltage-reactive curve is determined based on the local voltage characteristics, thereby determining the local voltage-reactive curve;

[0017] If the upper-layer optimization result is a voltage-reactive power curve, after verifying that the grid connection point voltage is stable, the local voltage-reactive power curve is updated to this voltage-reactive power curve.

[0018] Furthermore, when the upper-level optimization result is the grid-connected point reference voltage U0 and reactive power reference value Q0 of the inverter in a time period or moment, the specific process of setting the local voltage-reactive curve according to the reactive power reference value is: setting a dead zone interval on the traditional voltage-reactive curve, and setting the dead zone value to the reactive power reference value corresponding to the upper-level optimization result.

[0019] Furthermore, when the stable grid connection point voltage is not within the set voltage regulation range, a virtual voltage difference is set, and the specific operation process is as follows:

[0020] If the voltage amplitude of the grid connection point is greater than the upper limit of the set voltage regulation range, that is, V > V H , then the virtual voltage difference is superimposed on the currently measured grid-connected point voltage, so that the voltage-reactive power control curve is shifted to the left by the virtual voltage difference ΔV, so that the inverter absorbs more reactive power to reduce the voltage;

[0021] If the voltage amplitude at the grid connection point is less than the lower limit of the voltage regulation range, that is, V< V L , then the set virtual voltage difference is subtracted from the currently measured grid-connected point voltage, so that the voltage-reactive power control curve is shifted to the right by the virtual voltage difference, so that the inverter generates more reactive power to raise the voltage;

[0022] Repeat several times until the grid connection point voltage reaches the set voltage regulation range.

[0023] Furthermore, the grid connection point voltage value is periodically detected to obtain the maximum voltage and the minimum voltage within the cycle, and a voltage fluctuation threshold is set. When the difference between the maximum voltage and the minimum voltage within the cycle is greater than the voltage fluctuation threshold, it is determined that the grid connection voltage fluctuation is large.

[0024] Another object of the present invention is to provide a voltage-reactive power control device based on centralized optimization, comprising:

[0025] A detection module, used to detect and identify instructions sent by upper layer optimization;

[0026] A setting module, used to set the voltage regulation interval and set the local voltage-reactive power curve according to the recognized command result;

[0027] An output module is used to output a reactive power reference value of the inverter according to a set local voltage-reactive power curve;

[0028] A judgment module is used to control the reactive power of the inverter according to the reactive power reference value of the inverter, and then adjust the grid connection point voltage until it is stable; and judge whether the stable grid connection point voltage is within the set voltage adjustment range;

[0029] If yes, continue to adjust according to the local voltage-reactive power curve.

[0030] If not, the virtual voltage difference is added to the grid connection point voltage before regulation and then regulated;

[0031] The recovery module is used to periodically detect the voltage value of the grid connection point. When it is determined that the voltage fluctuation of the grid connection point is large, the accumulated voltage difference is set to zero and a signal is sent to the setting module.

[0032] The third object of the present invention is to provide a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, the processor executes the voltage-reactive power multi-mode optimization control method based on centralized optimization.

[0033] Beneficial effects:

[0034] 1) The present invention provides a flexible interface for the coordinated control of the upper layer control and the inverter.

[0035] 2) The present invention reasonably configures the upper-layer optimization results into a voltage-reactive power curve by dividing different operation modes and configuring curves in combination with local control characteristics, thereby improving the compatibility of the inverter with the upper-layer optimization and making the upper-layer optimization easier to implement.

[0036] 3) The adjusted curve of the present invention improves the suppression effect of overvoltage and voltage fluctuation, so that the voltage of the grid connection point is within the preset voltage operation range, while the tolerance to large fluctuations in the power grid and upper-level optimization errors and the effectiveness of regulation are enhanced.

[0037] 4) The present invention effectively suppresses grid voltage fluctuation and voltage over-limit, while improving the inverter voltage support capability and grid voltage quality.

[0038] 5) The present invention can ensure the safe grid-connected operation of installed or traditional photovoltaic inverters and ensure that the grid voltage meets the grid standard requirements.

[0039] 6) The present invention can improve the inverter's ability to suppress overvoltage and voltage fluctuations, while also improving the reliability of power grid operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a flow chart of Example 1;

[0041] Figure 2 This is the curve diagram after adding the dead zone;

[0042] Figure 3 The local voltage-reactive power curve determined when the upper optimization result is the slope of the voltage-reactive power curve;

[0043] Figure 4 This is a diagram illustrating the adaptive adjustment of voltage-reactive power curve;

[0044] Figure 5 It is the flow chart of voltage-reactive power curve adaptive regulation;

[0045] Figure 6 It is the transformer outlet voltage curve;

[0046] Figure 7 It is the reactive power output curve diagram of each photovoltaic inverter;

[0047] Figure 8 This is a comparison chart of the effects of using the present application and the existing adjustment method;

[0048] Fig. 9 This is a structural diagram of Example 2. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0050] Example 1

[0051] This embodiment is a voltage-reactive power multi-mode optimization control method based on centralized optimization, and the flow chart is as follows: Figure 1 As shown, including:

[0052] S1, detect and identify the instructions issued by the upper layer optimization; the instructions issued by the upper layer optimization include the reactive power reference value of the inverter in a time period or moment, the slope of the voltage-reactive curve, the voltage-reactive curve, the grid connection point reference voltage U0 and the grid connection point reactive power Q0;

[0053] S2, set the voltage adjustment range ( V L ≤ V ≤ V H ), and set the local voltage-reactive power curve according to the recognized instruction result; specifically:

[0054] If the upper optimization result is the grid-connected point reference voltage U0 and reactive power reference value Q0 of the inverter in a time period or moment, the local voltage-reactive power curve is set according to the grid-connected point reference voltage U0 and reactive power reference value Q0; Figure 2 As shown in the figure, the specific process is: set the dead zone interval (V3-V4) on the traditional voltage-reactive power curve, and set the dead zone value to the reactive power reference value Q0 corresponding to the upper optimization result. Where V3=U0-ΔU, V4=U0+ΔU, ΔU>0. ΔU is a constant value, usually 0.1; U0 is the grid connection point reference voltage, which is the value given by the upper instruction.

[0055] If the upper optimization result is the slope of the voltage-reactive power curve, set the upper and lower boundaries of the local voltage-reactive power curve based on the current inverter reactive power remaining capacity. Q max , Determine the reference voltage of the local voltage-reactive power curve based on the local voltage characteristics U ref (i.e. the intersection of the curve and the horizontal axis), and then determine the local voltage-reactive power curve, such as Figure 3 As shown;

[0056] If the upper-layer optimization result is a voltage-reactive power curve, after verifying that the grid connection point voltage is stable, the local voltage-reactive power curve is updated to this voltage-reactive power curve.

[0057] S3, outputting the reactive power reference value of the inverter according to the set local voltage-reactive power curve;

[0058] S4, regulating the reactive power of the inverter according to the reactive power reference value of the inverter, and then adjusting the grid connection point voltage until it is stable; judging whether the stable grid connection point voltage is within the set voltage adjustment range;

[0059] If not, a virtual voltage difference ΔV is set, and the regulation is performed after adding or subtracting the virtual voltage difference from the grid connection point voltage before regulation; as shown in the figure, specifically:

[0060] If the voltage amplitude of the grid connection point is greater than the upper limit of the set voltage regulation range, that is, V > V H, then the virtual voltage difference is superimposed on the currently measured grid-connected point voltage, so that the voltage-reactive power control curve is shifted to the left by the virtual voltage difference ΔV, so that the inverter absorbs more reactive power to reduce the voltage;

[0061] If the voltage amplitude at the grid connection point is less than the lower limit of the voltage regulation range, that is, V< V L , then the virtual voltage difference ΔV is subtracted from the currently measured grid-connected point voltage, so that the voltage-reactive power control curve is shifted to the right by the virtual voltage difference ΔV, thereby causing the inverter to generate more reactive power to raise the voltage;

[0062] like Figure 4 As shown, the red curve is the actual operation curve, and its intersection with the voltage-reactive power curve before adjustment is the stable operation point V1, and its intersection with the voltage-reactive power curve after adjustment is the stable operation point V2.

[0063] Repeat the above process until the grid connection point voltage reaches the set voltage regulation range;

[0064] like Figure 5 As shown, the virtual voltage difference is ΔV, the cumulative voltage difference of the current cycle (i.e., the kth time) is recorded as ΔV(k), the cumulative voltage difference of the next cycle (i.e., the k+1th time) is recorded as ΔV(k+1), the virtual voltage of the next cycle is recorded as V*(k+1), the current detected grid-connected point voltage is V(k+1), ΔV(k+1)=ΔV(k)+ / -ΔV, V*(k+1)=V(k+1)+ΔV(k+1). Figure 5 The VVC in this figure refers to the voltage-reactive power control curve.

[0065] when V > V H , ΔV(k+1)=ΔV(k)+ΔV, V*(k+1)=V(k+1)+ΔV(k+1);

[0066] When V< V L , ΔV(k+1)=ΔV(k)-ΔV, V*(k+1)=V(k+1)+ΔV(k+1);

[0067] The V*(k+1) input voltage-reactive curve is used to calculate the reactive power reference value (Q(k+1)ref = f(V*(k+1))), where f(x) is the set voltage-reactive curve. Until the grid-connected point voltage reaches the set voltage regulation range, the superimposed virtual voltage difference is maintained for voltage-reactive regulation.

[0068] If yes, continue to adjust according to the local voltage-reactive power curve; Figure 5 As shown, when V L ≤ V ≤ V H , ΔV(k+1)=ΔV(k), and the curve does not need to be adjusted.

[0069] S5, periodically detect the voltage value of the grid connection point. When it is determined that the voltage fluctuation of the grid connection point is large, that is, when it is detected that the operation of the distribution network has changed significantly, the accumulated voltage difference is set to zero, and then return to step S2, and then adjust according to the set voltage-reactive power curve; the condition for determining that the voltage fluctuation of the grid connection point is large is:

[0070] like Figure 5 As shown, the grid voltage value is periodically detected to obtain the maximum voltage V within the cycle. max and voltage minimum value V min , and set the voltage fluctuation threshold V limit , when the difference between the maximum voltage and the minimum voltage within 10 cycles is greater than the voltage fluctuation threshold, that is, V max -V min ≥V limit , it is judged that the grid voltage fluctuation is large.

[0071] Applying the algorithm of the present invention to a certain area, the grid transformer outlet voltage can be obtained: Figure 2 As shown, the photovoltaic inverter is controlled by the patented method of the present invention. When the load in the substation fluctuates, the reactive power output of the photovoltaic inverter is adjusted by the method of the present invention to ensure that the outlet voltage of the substation grid transformer is stable at around 1.01pu.

[0072] The transformer outlet voltage curve is as follows: Figure 6 shown.

[0073] Each photovoltaic inverter in the substation actively adjusts the reactive power output as the photovoltaic power generation and load power change to achieve effective regulation of the grid connection point voltage. The reactive power output of each photovoltaic inverter is as follows: Figure 7 shown.

[0074] according to Figure 8 It can be seen that when the photovoltaic inverter does not adjust the reactive power, the voltage at the grid point exceeds the limit seriously, and the voltage exceeds 1.08pu; the photovoltaic inverter can reduce the grid point voltage to 1.05pu through local voltage-reactive power control, and the overvoltage situation is still serious. According to the patented method of the present invention, the reactive power output of the inverter can be controlled to reduce the grid point voltage to 1.02pu. The proposed method has an obvious effect on the voltage regulation of the grid point. Comparing the voltage conditions of the substation under the three conditions of the algorithm of the present invention, the traditional adjustment algorithm and no adjustment, it can be proved that the algorithm of the present invention can more effectively regulate the voltage of each grid point in the substation.

[0075] Example 2

[0076] The embodiment is a voltage-reactive power control device based on centralized optimization, such as Fig. 9 As shown, including:

[0077] A detection module, used to detect and identify instructions sent by upper layer optimization;

[0078] A setting module, used to set the voltage regulation interval and set the local voltage-reactive power curve according to the recognized command result;

[0079] An output module is used to output a reactive power reference value of the inverter according to a set local voltage-reactive power curve;

[0080] A judgment module is used to control the reactive power of the inverter according to the reactive power reference value of the inverter, and then adjust the grid connection point voltage until it is stable; and judge whether the stable grid connection point voltage is within the set voltage adjustment range;

[0081] If yes, continue to adjust according to the local voltage-reactive power curve.

[0082] If not, the virtual voltage difference is added to the grid connection point voltage before regulation and then regulated;

[0083] The recovery module is used to periodically detect the voltage value of the grid connection point. When it is determined that the voltage fluctuation of the grid connection point is large, the accumulated voltage difference is set to zero and a signal is sent to the setting module.

[0084] Example 3

[0085] A computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the processor executes the voltage-reactive power multi-mode optimization control method based on centralized optimization described in Example 1.

[0086] It should be noted that the embodiments of the present invention can be implemented by hardware, software, or a combination of software and hardware. The hardware part can be implemented using dedicated logic; the software part can be stored in a memory and executed by an appropriate instruction execution system, such as a microprocessor or dedicated design hardware. It can be understood by a person of ordinary skill in the art that the above-mentioned devices and methods can be implemented using computer executable instructions and / or contained in a processor control code, such as a carrier medium such as a disk, CD or DVD-ROM, a programmable memory such as a read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. Such code is provided on the carrier medium. The device and its modules of the present invention can be implemented by hardware circuits such as very large-scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, etc., or programmable hardware devices such as field programmable gate arrays, programmable logic devices, etc., can also be implemented by software executed by various types of processors, and can also be implemented by a combination of the above-mentioned hardware circuits and software, such as firmware.

[0087] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modification, equivalent substitution and improvement made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A voltage-reactive power multi-mode optimization control method based on centralized optimization, characterized in that: include: S1, detects and identifies the instructions sent by the upper layer optimization; S2, setting the voltage regulation interval and setting the local voltage-reactive power curve according to the recognized command result; S3, outputting the reactive power reference value of the inverter according to the set local voltage-reactive power curve; S4, regulating the reactive power of the inverter according to the reactive power reference value of the inverter, and then adjusting the grid connection point voltage until it is stable; judging whether the stable grid connection point voltage is within the set voltage adjustment range; If yes, continue to regulate according to the set local voltage-reactive power curve; If not, set a virtual voltage difference, and adjust the grid connection point voltage by adding or subtracting the virtual voltage difference before adjustment; repeat several times until the grid connection point voltage reaches the set voltage adjustment range and the accumulated voltage difference is obtained; the specific operation process is: If the voltage amplitude at the grid connection point is greater than the upper limit of the set voltage regulation range, the set virtual voltage difference is superimposed on the currently measured grid connection point voltage to shift the voltage-reactive power control curve to the left by the virtual voltage difference, so that the inverter absorbs more reactive power to reduce the voltage. If the voltage amplitude at the grid connection point is less than the lower limit of the set voltage regulation range, the set virtual voltage difference is subtracted from the currently measured grid connection point voltage to shift the voltage-reactive power control curve to the right by the virtual voltage difference, so that the inverter generates more reactive power to raise the voltage. Repeat several times until the grid connection point voltage reaches the set voltage regulation range; S5, periodically detect the voltage value of the grid connection point. When it is determined that the voltage fluctuation of the grid connection point is large, that is, when a large change in the operation of the distribution network is detected, the accumulated voltage difference is set to zero, and then return to step S2, and then adjust according to the set voltage-reactive power curve.

2. The voltage-reactive power multi-mode optimization control method based on centralized optimization according to claim 1, characterized in that: The instructions sent by the upper layer optimization include the reactive power reference value, voltage-reactive power curve slope, voltage-reactive power curve, grid connection point reference voltage and reactive power reference value of the inverter in a time period or moment.

3. The voltage-reactive power multi-mode optimization control method based on centralized optimization according to claim 2, characterized in that: If the upper layer optimization result is the grid connection point reference voltage and reactive power reference value of the inverter in a time period or moment, the local voltage-reactive power curve is set according to the grid connection point reference voltage and reactive power reference value; If the upper optimization result is the slope of the voltage-reactive curve, the upper and lower boundaries of the local voltage-reactive curve are set based on the current reactive remaining capacity of the inverter, and the reference voltage of the local voltage-reactive curve is determined based on the local voltage characteristics, thereby determining the local voltage-reactive curve; If the upper-layer optimization result is a voltage-reactive power curve, after verifying that the grid connection point voltage is stable, the local voltage-reactive power curve is updated to this voltage-reactive power curve.

4. The voltage-reactive power multi-mode optimization control method based on centralized optimization according to claim 2 or 3, characterized in that: When the upper-level optimization result is the grid-connected point reference voltage and reactive power reference value of the inverter in a time period or moment, the local voltage-reactive curve is set according to the grid-connected point reference voltage and reactive power reference value. The specific process is: setting a dead zone interval on the traditional voltage-reactive curve, and setting the dead zone value to the reactive power reference value corresponding to the upper-level optimization result.

5. The voltage-reactive power multi-mode optimization control method based on centralized optimization according to claim 1, characterized in that: The grid connection point voltage value is periodically detected to obtain the maximum and minimum voltage values ​​within the cycle, and a voltage fluctuation threshold is set. When the difference between the maximum and minimum voltage values ​​within the cycle is greater than the voltage fluctuation threshold, it is judged that the grid connection voltage fluctuation is large.

6. A voltage-reactive power control device based on centralized optimization, adopting the voltage-reactive power multi-mode optimization control method based on centralized optimization according to any one of claims 1 to 5, comprising: A detection module, used to detect and identify instructions sent by upper layer optimization; A setting module, used to set the voltage regulation interval and set the local voltage-reactive power curve according to the recognized command result; An output module is used to output a reactive power reference value of the inverter according to a set local voltage-reactive power curve; A judgment module is used to control the reactive power of the inverter according to the reactive power reference value of the inverter, and then adjust the grid connection point voltage until it is stable; and judge whether the stable grid connection point voltage is within the set voltage adjustment range; If yes, continue to adjust according to the local voltage-reactive power curve. If not, the virtual voltage difference is added to the grid connection point voltage before regulation and then regulated; The recovery module is used to periodically detect the voltage value of the grid connection point. When it is determined that the voltage fluctuation of the grid connection point is large, the accumulated voltage difference is set to zero and a signal is sent to the setting module.

7. A computer-readable storage medium storing a computer program, which, when executed by a processor, enables the processor to execute the voltage-reactive power multi-mode optimization control method based on centralized optimization as described in any one of claims 1 to 5.

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