Substation voltage control method and device based on reactive power compensation of photovoltaic grid-connected device

Abstract

The present invention discloses a method and device for regulating the voltage of a substation based on reactive compensation of a photovoltaic grid-connected device. The method for regulating the voltage of a substation based on reactive compensation of a photovoltaic grid-connected device includes: formulating a segmented reactive control strategy based on the voltage fluctuation of the photovoltaic grid-connected point and the real-time available capacity of the photovoltaic grid-connected device, wherein the segmented reactive control strategy is used to determine the reactive increment adjustment amount of the photovoltaic grid-connected device under different fluctuations of the grid-connected point voltage; revising the segmented reactive control strategy based on the reactive operating range of the photovoltaic grid-connected device; and determining the reactive command of the photovoltaic grid-connected device according to the segmented reactive control strategy before and after the revision, and issuing the reactive command to the photovoltaic grid-connected device.

Description

Technical Field

[0001] The present invention relates to the technical field of power quality management, and more specifically, to a method and device for managing voltage in an area based on reactive power compensation of a photovoltaic grid-connected device, as well as a storage medium and an electronic device. Background Art

[0002] Voltage management is one of the main problems faced by substation operation control, especially low voltage management. At present, the common method is to configure SVG devices on the low-voltage side of the substation distribution transformer to perform continuous dynamic reactive power compensation on the low-voltage bus to ensure that the voltage on the low-voltage side of the distribution transformer operates within the normal range. However, this method increases the cost of substation equipment configuration, operation and maintenance management, and cannot effectively solve the voltage problem at the end of the substation line, and the substation voltage management capability is poor.

[0003] With the "carbon neutrality and carbon peak" goals proposed, the installed capacity of distributed photovoltaic power generation has further increased rapidly. At present, photovoltaic grid-connected power generation mainly adopts MPPT operation mode, which does not participate in the active support of the power grid. However, photovoltaic grid-connected devices have good reactive voltage regulation potential. Combined with the utilization of its reactive regulation resources, it can greatly improve the voltage management capacity of the substation, save the configuration of SVG devices in the substation, reduce the construction cost of the substation, and improve the overall benefits of photovoltaic grid-connected power generation.

[0004] However, there is currently a lack of a technical solution that can utilize the reactive voltage regulation resources of photovoltaic grid-connected devices to manage the voltage in the substation area, which makes it impossible to improve the photovoltaic grid-connected operation efficiency in the substation area and reduce the SVG configuration cost in the substation area. Summary of the invention

[0005] In order to solve the above-mentioned technical problem of lack of a technical solution that can utilize the reactive voltage regulation resources of photovoltaic grid-connected devices to manage the voltage in the substation area, thereby failing to improve the photovoltaic grid-connected operation efficiency of the substation area and failing to reduce the SVG configuration cost of the substation area, the present invention proposes a substation voltage management method, device, storage medium and electronic device based on reactive power compensation of photovoltaic grid-connected devices. Focusing on the substation voltage management problem and combining the photovoltaic reactive power regulation space in the substation area, a method for dynamic rapid reactive power compensation of photovoltaic grid-connected devices is proposed, which adjusts the reactive power of photovoltaic grid-connected devices in real time based on the voltage fluctuation of the substation area, improves the dynamic characteristics of the substation voltage, improves the safe operation level of the substation voltage, improves the power supply quality of the substation area, and also reduces the SVG configuration cost of the substation area.

[0006] According to one aspect of the present invention, a method for regulating voltage in an area based on reactive power compensation of a photovoltaic grid-connected device is provided, comprising:

[0007] Based on the voltage fluctuation of the photovoltaic grid-connected point and the real-time available capacity of the photovoltaic grid-connected device, a segmented reactive power control strategy is formulated, wherein the segmented reactive power control strategy is used to determine the reactive power increment adjustment amount of the photovoltaic grid-connected device under different voltage fluctuations at the grid-connected point;

[0008] Based on the reactive operation range of the photovoltaic grid-connected device, modifying the segmented reactive power control strategy; and

[0009] According to the segmented reactive power control strategy before correction and the segmented reactive power control strategy after correction, the reactive power instruction of the photovoltaic grid-connected device is determined, and the reactive power instruction is issued to the photovoltaic grid-connected device.

[0010] Optionally, the method further comprises:

[0011] According to the real-time available capacity of the photovoltaic grid-connected device and the active output at different times, the reactive power regulation operation boundary of the photovoltaic grid-connected device is constructed, wherein the reactive power regulation operation boundary is used to indicate the correlation between the reactive power instruction of the photovoltaic grid-connected device at different times and the maximum reactive power allowed for the operation of the photovoltaic grid-connected device.

[0012] Optionally, the reactive power regulation operation boundary of the photovoltaic grid-connected device is:

[0013]

[0014] Among them, S PV is the capacity of the photovoltaic grid-connected device, P PV,t is the active output of the photovoltaic grid-connected device at time t, Q PV,set,t is the reactive power command of the photovoltaic grid-connected device at time t, Q PV,max,t It is the maximum reactive power output allowed by the photovoltaic grid-connected device at time t.

[0015] Optionally, the segmented reactive power control strategy is: when the voltage fluctuation of the photovoltaic grid-connected point is in the regulation dead zone, the reactive power increment that needs to be adjusted by the photovoltaic grid-connected device is equal to zero; when the voltage fluctuation of the photovoltaic grid-connected point exceeds the regulation dead zone, the reactive power increment that needs to be adjusted by the photovoltaic grid-connected device is linearly adjusted based on droop control.

[0016] Optionally, the calculation formula of the segmented reactive power control strategy is as follows:

[0017]

[0018] Among them, ΔQ PV,set,t is the reactive power increment regulation of the photovoltaic grid-connected device at time t, U t is the grid connection point voltage of the photovoltaic grid-connected device at time t, U n is the nominal voltage of the power distribution system in the substation, Ku is the voltage regulation coefficient and ε is the regulation dead zone.

[0019] Optionally, the modified segmented reactive power control strategy is:

[0020]

[0021] Among them, ΔQ' PV,set,t is the modified reactive increment regulation of the photovoltaic grid-connected device at time t, Q PV,set,t-1 It is the reactive power instruction of the photovoltaic grid-connected device at time t-1.

[0022] Optionally, the reactive power instruction of the photovoltaic grid-connected device is:

[0023] Q PV,set,t =Q PV,set,t-1 +ΔQ' PV,set,t

[0024] Among them, Q PV,set,t is the reactive power command of the photovoltaic grid-connected device at time t, Q PV,set,t-1 is the reactive power command of the photovoltaic grid-connected device at time t-1, ΔQ' PV,set,t It is the modified reactive increment regulation value of the photovoltaic grid-connected device at time t.

[0025] According to another aspect of the present invention, there is provided a station area voltage management device based on reactive power compensation of a photovoltaic grid-connected device, comprising:

[0026] A strategy formulation module, for formulating a segmented reactive power control strategy based on the voltage fluctuation of the photovoltaic grid-connected point and the real-time available capacity of the photovoltaic grid-connected device, wherein the segmented reactive power control strategy is used to determine the reactive power increment adjustment amount of the photovoltaic grid-connected device under different voltage fluctuations at the grid-connected point;

[0027] A strategy correction module, used to correct the segmented reactive power control strategy based on the reactive power operation range of the photovoltaic grid-connected device; and

[0028] The reactive power instruction determination module is used to determine the reactive power instruction of the photovoltaic grid-connected device according to the segmented reactive power control strategy before correction and the segmented reactive power control strategy after correction, and issue the reactive power instruction to the photovoltaic grid-connected device.

[0029] Optionally, the device further comprises:

[0030] The reactive power regulation operation boundary construction module is used to construct the reactive power regulation operation boundary of the photovoltaic grid-connected device according to the real-time available capacity of the photovoltaic grid-connected device and the active power output at different times, wherein the reactive power regulation operation boundary is used to indicate the correlation between the reactive power instruction of the photovoltaic grid-connected device at different times and the maximum reactive power output allowed for the operation of the photovoltaic grid-connected device.

[0031] Optionally, the reactive power regulation operation boundary of the photovoltaic grid-connected device is:

[0032]

[0033] Among them, S PV is the capacity of the photovoltaic grid-connected device, P PV,t is the active output of the photovoltaic grid-connected device at time t, Q PV,set,t is the reactive power command of the photovoltaic grid-connected device at time t, Q PV,max,t It is the maximum reactive power output allowed by the photovoltaic grid-connected device at time t.

[0034] Optionally, the segmented reactive power control strategy is: when the voltage fluctuation of the photovoltaic grid-connected point is in the regulation dead zone, the reactive power increment that needs to be adjusted by the photovoltaic grid-connected device is equal to zero; when the voltage fluctuation of the photovoltaic grid-connected point exceeds the regulation dead zone, the reactive power increment that needs to be adjusted by the photovoltaic grid-connected device is linearly adjusted based on droop control.

[0035] Optionally, the calculation formula of the segmented reactive power control strategy is as follows:

[0036]

[0037] Among them, ΔQ PV,set,t is the reactive power increment regulation of the photovoltaic grid-connected device at time t, U t is the grid connection point voltage of the photovoltaic grid-connected device at time t, U n is the nominal voltage of the power distribution system in the substation, K u is the voltage regulation coefficient and ε is the regulation dead zone.

[0038] Optionally, the modified segmented reactive power control strategy is:

[0039]

[0040] Among them, ΔQ' PV,set,t is the modified reactive increment regulation of the photovoltaic grid-connected device at time t, Q PV,set,t-1 It is the reactive power instruction of the photovoltaic grid-connected device at time t-1.

[0041] Optionally, the reactive power instruction of the photovoltaic grid-connected device is:

[0042] QPV,set,t =Q PV,set,t-1 +ΔQ' PV,set,t

[0043] Among them, Q PV,set,t is the reactive power command of the photovoltaic grid-connected device at time t, Q PV,set,t-1 is the reactive power command of the photovoltaic grid-connected device at time t-1, ΔQ' PV,set,t It is the modified reactive increment regulation value of the photovoltaic grid-connected device at time t.

[0044] According to another aspect of the present invention, a computer-readable storage medium is provided, wherein the storage medium stores a computer program, and the computer program is used to execute the method described in any one of the above aspects of the present invention.

[0045] According to another aspect of the present invention, an electronic device is provided, comprising: a processor; a memory for storing instructions executable by the processor; the processor is configured to read the executable instructions from the memory and execute the instructions to implement the method described in any one of the above aspects of the present invention.

[0046] Therefore, the method and device for regulating the voltage in the substation based on reactive power compensation of the photovoltaic grid-connected device proposed in the present invention first read the operating status of the photovoltaic grid-connected device and the voltage data of the grid-connected point, build the reactive power regulation operation boundary of the photovoltaic grid-connected device, and then establish the coupling relationship between the reactive power control of the photovoltaic grid-connected device and the voltage of the grid-connected point. According to the voltage fluctuation of the photovoltaic grid-connected point and the real-time available capacity of the photovoltaic grid-connected device, the segmented reactive power regulation strategy is designed, the reactive power instruction of the photovoltaic grid-connected device is dynamically adjusted, and the corresponding reactive power instruction is issued to the photovoltaic grid-connected device. Thus, the corresponding reactive power is quickly provided by the internal response of the photovoltaic grid-connected device itself, the substation voltage regulation based on the reactive power compensation of the photovoltaic grid-connected device is realized, the continuous compensation of the local reactive power is realized, and the voltage regulation capacity of the substation is effectively improved. Moreover, on the basis of the original maximum power point tracking operation mode, the available capacity resources of the photovoltaic grid-connected device are fully utilized, the dynamic characteristics of the substation voltage are improved, clean power generation is realized, and active support is provided for the distribution system, the operation efficiency of the photovoltaic grid-connected device is effectively improved, and the configuration cost of the substation SVG is also reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0048] Figure 1 It is a flow chart of a method for controlling voltage in a substation based on reactive power compensation of a photovoltaic grid-connected device provided by an exemplary embodiment of the present invention;

[0049] Figure 2 It is a schematic diagram of reactive power compensation of a photovoltaic grid-connected device in a substation area provided by an exemplary embodiment of the present invention;

[0050] Figure 3 It is a schematic diagram of a reactive power control strategy for a photovoltaic grid-connected device in a substation provided by an exemplary embodiment of the present invention;

[0051] Figure 4 is a structural schematic diagram of a station area voltage management device based on reactive power compensation of a photovoltaic grid-connected device provided by an exemplary embodiment of the present invention; and

[0052] Figure 5 This is a structure of an electronic device provided by an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0053] Below, the exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments of the present invention, and it should be understood that the present invention is not limited to the exemplary embodiments described here.

[0054] It should be noted that the relative arrangement of components and steps, the numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

[0055] Those skilled in the art can understand that the terms "first" and "second" in the embodiments of the present invention are only used to distinguish different steps, devices or modules, etc., and neither represent any specific technical meaning nor indicate the necessary logical order between them.

[0056] It should also be understood that, in the embodiments of the present invention, “plurality” may refer to two or more than two, and “at least one” may refer to one, two or more than two.

[0057] It should also be understood that any component, data or structure mentioned in the embodiments of the present invention can generally be understood as one or more, unless explicitly limited or otherwise indicated in the context.

[0058] In addition, the term "and / or" in the present invention is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present invention generally indicates that the associated objects before and after are in an "or" relationship.

[0059] It should also be understood that the description of the various embodiments of the present invention focuses on the differences between the various embodiments, and the same or similar aspects thereof can be referenced to each other, and for the sake of brevity, they will not be described one by one.

[0060] At the same time, it should be understood that for the convenience of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship.

[0061] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0062] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered part of the specification.

[0063] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0064] Embodiments of the present invention can be applied to electronic devices such as terminal devices, computer systems, servers, etc., which can operate with many other general or special computing system environments or configurations. Examples of well-known terminal devices, computing systems, environments and / or configurations suitable for use with electronic devices such as terminal devices, computer systems, servers, etc. include, but are not limited to: personal computer systems, server computer systems, thin clients, thick clients, handheld or laptop devices, microprocessor-based systems, set-top boxes, programmable consumer electronics, network personal computers, small computer systems, large computer systems, and distributed cloud computing technology environments including any of the above systems, etc.

[0065] Electronic devices such as terminal devices, computer systems, servers, etc. can be described in the general context of computer system executable instructions (such as program modules) executed by computer systems. Generally, program modules can include routines, programs, object programs, components, logic, data structures, etc., which perform specific tasks or implement specific abstract data types. Computer systems / servers can be implemented in a distributed cloud computing environment, where tasks are performed by remote processing devices linked through a communication network. In a distributed cloud computing environment, program modules can be located on local or remote computing system storage media including storage devices.

[0066] Exemplary Methods

[0067] Figure 1 1 is a flow chart of a method for controlling voltage in a substation based on reactive power compensation of a photovoltaic grid-connected device provided by an exemplary embodiment of the present invention. This embodiment can be applied to electronic devices, such as Figure 1 As shown, the following steps are included:

[0068] Step 101, based on the voltage fluctuation of the photovoltaic grid-connected point and the real-time available capacity of the photovoltaic grid-connected device, a segmented reactive power control strategy is formulated, wherein the segmented reactive power control strategy is used to determine the reactive power increment adjustment amount of the photovoltaic grid-connected device when the voltage of the grid-connected point fluctuates differently.

[0069] Specifically, since the current substation voltage management device SVG is mainly installed on the low-voltage side of the distribution transformer, centralized reactive power compensation is performed at the head end of the substation, which cannot fundamentally and effectively solve the voltage problems at other nodes of the substation distribution line, especially at the end. Therefore, this embodiment combines the photovoltaic grid-connected device resources at other nodes of the substation distribution line to establish a coupling relationship between the reactive power control of the photovoltaic grid-connected device and the grid-connected point voltage. According to the voltage fluctuation of the photovoltaic grid-connected point and the real-time available capacity of the photovoltaic grid-connected device, a segmented reactive power control strategy is formulated to determine the reactive power increment adjustment amount of the photovoltaic grid-connected device when the grid-connected point voltage fluctuates differently, thereby dynamically and continuously compensating for reactive power and effectively improving the substation voltage management capability.

[0070] Optionally, the segmented reactive power control strategy is: when the voltage fluctuation of the photovoltaic grid-connected point is in the regulation dead zone, the reactive power increment that needs to be adjusted by the photovoltaic grid-connected device is equal to zero; when the voltage fluctuation of the photovoltaic grid-connected point exceeds the regulation dead zone, the reactive power increment that needs to be adjusted by the photovoltaic grid-connected device is linearly adjusted based on droop control.

[0071] As an embodiment, the calculation formula of the segmented reactive power control strategy is as follows:

[0072]

[0073] Among them, ΔQ PV,set,t is the reactive power increment regulation of the photovoltaic grid-connected device at time t, U t is the grid connection point voltage of the photovoltaic grid-connected device at time t, U n is the nominal voltage of the power distribution system in the substation, K u is the voltage regulation coefficient and ε is the regulation dead zone.

[0074] In addition, according to an exemplary embodiment, the method further includes: constructing a reactive power regulation operation boundary of the photovoltaic grid-connected device according to the real-time available capacity of the photovoltaic grid-connected device and the active power output at different times, wherein the reactive power regulation operation boundary is used to indicate the correlation between the reactive power instruction of the photovoltaic grid-connected device at different times and the maximum reactive power allowed for the operation of the photovoltaic grid-connected device.

[0075] Furthermore, in one embodiment, the reactive power regulation operation boundary of the photovoltaic grid-connected device is:

[0076]

[0077] Among them, SPV is the capacity of the photovoltaic grid-connected device, P PV,t is the active output of the photovoltaic grid-connected device at time t, Q PV,set,t is the reactive power command of the photovoltaic grid-connected device at time t, Q PV,max,t It is the maximum reactive power output allowed by the photovoltaic grid-connected device at time t.

[0078] Specifically, refer to Figure 2 As shown, the method proposed in this embodiment also needs to read the operating status of the photovoltaic grid-connected device and the grid-connected point voltage data, and build the reactive power regulation operation boundary of the photovoltaic grid-connected device. The reactive power regulation operation boundary is used to indicate the correlation between the reactive power instruction of the photovoltaic grid-connected device at different times and the maximum reactive power output allowed by the operation of the photovoltaic grid-connected device. Thus, it provides a basis for the subsequent correction of the segmented reactive power control strategy.

[0079] Step 102: based on the reactive power operation range of the photovoltaic grid-connected device, modify the segmented reactive power control strategy.

[0080] Specifically, considering the difference characteristics of reactive power compensation under different voltage fluctuations, not only a segmented reactive power control strategy is designed, but also based on the voltage fluctuation of the grid-connected point of the photovoltaic grid-connected device and the reactive power operation range of the photovoltaic grid-connected device in the reactive power regulation operation boundary, the segmented reactive power control strategy is corrected.

[0081] Optionally, the modified segmented reactive power control strategy is:

[0082]

[0083] Among them, ΔQ' PV,set,t is the modified reactive increment regulation of the photovoltaic grid-connected device at time t, Q PV,set,t-1 It is the reactive power instruction of the photovoltaic grid-connected device at time t-1.

[0084] Step 103, determining a reactive power instruction of the photovoltaic grid-connected device according to the segmented reactive power control strategy before correction and the segmented reactive power control strategy after correction, and issuing the reactive power instruction to the photovoltaic grid-connected device.

[0085] Optionally, the reactive power instruction of the photovoltaic grid-connected device is:

[0086] Q PV,set,t =Q PV,set,t-1 +ΔQ' PV,set,t

[0087] Among them, Q PV,set,t is the reactive power command of the photovoltaic grid-connected device at time t, Q PV,set,t-1 is the reactive power command of the photovoltaic grid-connected device at time t-1, ΔQ' PV,set,tIt is the modified reactive increment regulation value of the photovoltaic grid-connected device at time t.

[0088] Specifically, this embodiment combines the segmented reactive power control strategy before correction with the segmented reactive power control strategy after correction to determine the reactive power instruction of the photovoltaic grid-connected device. Figure 3 As shown, the substation voltage management method based on reactive power compensation of photovoltaic grid-connected devices proposed in this embodiment adjusts the reactive output command of photovoltaic grid-connected devices in real time based on the substation voltage fluctuation, realizes localized continuous reactive power compensation, thereby improving the dynamic characteristics of the substation voltage, effectively improving the safe operation level of the substation voltage, and improving the power supply quality of the substation.

[0089] Therefore, the method for controlling the voltage in the substation area based on reactive power compensation of the photovoltaic grid-connected device proposed in this embodiment has the following characteristics and advantages:

[0090] 1) Improve the voltage management level of the distribution line in the substation. At present, the substation voltage management device SVG is mainly installed on the low-voltage side of the distribution transformer, and centralized reactive power compensation is performed at the head end of the substation, which cannot effectively solve the voltage problems at other nodes of the substation distribution line, especially at the end. Combined with the photovoltaic grid-connected device resources at other nodes of the substation distribution line, dynamic and continuous reactive power compensation can be performed to effectively improve the voltage management capacity of the substation.

[0091] 2) Realize continuous local reactive power compensation for photovoltaic grid-connected devices. Considering the difference in reactive power compensation under different voltage fluctuations, a segmented reactive power control strategy is designed. Based on the voltage fluctuation at the grid-connected point of the photovoltaic grid-connected device, the reactive output command of the photovoltaic grid-connected device is adjusted in real time to realize continuous local reactive power compensation.

[0092] 3) Improve the efficiency of photovoltaic grid-connected operation in the substation. On the basis of the original maximum power point tracking operation mode, give full play to the available capacity resources of photovoltaic grid-connected devices, improve the dynamic characteristics of substation voltage, realize clean power generation and provide active support for the distribution system, effectively improve the efficiency of photovoltaic grid-connected operation, and reduce the configuration cost of SVG in the substation.

[0093] Exemplary Devices

[0094] Figure 4 FIG. 1 is a schematic diagram of a voltage management device for a substation based on reactive power compensation of a photovoltaic grid-connected device provided by an exemplary embodiment of the present invention. Figure 4 As shown, this embodiment includes:

[0095] A strategy formulation module 41 is used to formulate a segmented reactive power control strategy based on the voltage fluctuation of the photovoltaic grid-connected point and the real-time available capacity of the photovoltaic grid-connected device, wherein the segmented reactive power control strategy is used to determine the reactive power increment adjustment amount of the photovoltaic grid-connected device when the voltage of the grid-connected point fluctuates differently;

[0096] A strategy correction module 42, configured to correct the segmented reactive power control strategy based on the reactive power operation range of the photovoltaic grid-connected device; and

[0097] The reactive power instruction determination module 43 is used to determine the reactive power instruction of the photovoltaic grid-connected device according to the segmented reactive power control strategy before correction and the segmented reactive power control strategy after correction, and issue the reactive power instruction to the photovoltaic grid-connected device.

[0098] In one embodiment, the apparatus further comprises:

[0099] The reactive power regulation operation boundary construction module is used to construct the reactive power regulation operation boundary of the photovoltaic grid-connected device according to the real-time available capacity of the photovoltaic grid-connected device and the active power output at different times, wherein the reactive power regulation operation boundary is used to indicate the correlation between the reactive power instruction of the photovoltaic grid-connected device at different times and the maximum reactive power output allowed for the operation of the photovoltaic grid-connected device.

[0100] Optionally, the reactive power regulation operation boundary construction module is specifically used to construct the following reactive power regulation operation boundary:

[0101]

[0102] Among them, S PV is the capacity of the photovoltaic grid-connected device, P PV,t is the active output of the photovoltaic grid-connected device at time t, Q PV,set,t is the reactive power command of the photovoltaic grid-connected device at time t, Q PV,max,t It is the maximum reactive power output allowed by the photovoltaic grid-connected device at time t.

[0103] Optionally, the strategy formulation module is specifically used for: when the voltage fluctuation of the photovoltaic grid-connected point is in the regulation dead zone, the reactive increment that needs to be adjusted by the photovoltaic grid-connected device is equal to zero; when the voltage fluctuation of the photovoltaic grid-connected point exceeds the regulation dead zone, linearly adjusting the reactive increment that needs to be adjusted by the photovoltaic grid-connected device based on droop control.

[0104] Optionally, the strategy formulation module is specifically used to formulate the following segmented reactive power control strategy:

[0105]

[0106] Among them, ΔQ PV,set,t is the reactive power increment regulation of the photovoltaic grid-connected device at time t, U t is the grid connection point voltage of the photovoltaic grid-connected device at time t, U n is the nominal voltage of the power distribution system in the substation, K u is the voltage regulation coefficient and ε is the regulation dead zone.

[0107] Optionally, the strategy correction module is specifically used to correct and obtain the following segmented reactive power control strategy:

[0108]

[0109] Among them, ΔQ' PV,set,t is the modified reactive increment regulation of the photovoltaic grid-connected device at time t, Q PV,set,t-1 It is the reactive power instruction of the photovoltaic grid-connected device at time t-1.

[0110] Optionally, the reactive power instruction determination module is specifically used to determine the following reactive power instructions:

[0111] Q PV,set,t =Q PV,set,t-1 +ΔQ' PV,set,t

[0112] Among them, Q PV,set,t is the reactive power command of the photovoltaic grid-connected device at time t, Q PV,set,t-1 is the reactive power command of the photovoltaic grid-connected device at time t-1, ΔQ' PV,set,t It is the modified reactive increment regulation value of the photovoltaic grid-connected device at time t.

[0113] Exemplary Electronic Devices

[0114] Figure 5 The electronic device provided by an exemplary embodiment of the present invention may be any one or both of the first device and the second device, or a stand-alone device independent of them, and the stand-alone device may communicate with the first device and the second device to receive the collected input signals from them. Figure 5 FIG. 2 is a block diagram of an electronic device according to an embodiment of the present invention. Figure 5 As shown, the electronic device 50 includes one or more processors 51 and a memory 52 .

[0115] The processor 51 may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions.

[0116] The memory 52 may include one or more computer program products, and the computer program product may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory (cache), etc. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 51 may run the program instructions to implement the method for information mining of historical change records and / or other desired functions of the software program of each embodiment of the present invention described above. In one example, the electronic device may also include: an input device 53 and an output device 54, and these components are interconnected through a bus system and / or other forms of connection mechanisms (not shown).

[0117] In addition, the input device 53 may also include, for example, a keyboard, a mouse, etc.

[0118] The output device 54 can output various information to the outside. The output device 54 can include, for example, a display, a speaker, a printer, a communication network and a remote output device connected thereto.

[0119] Of course, to simplify, Figure 5 Only some of the components related to the present invention in the electronic device are shown, and components such as a bus, an input / output interface, etc. are omitted. In addition, according to specific application conditions, the electronic device may also include any other appropriate components.

[0120] Exemplary computer program products and computer-readable storage media

[0121] In addition to the above-mentioned methods and devices, an embodiment of the present invention may also be a computer program product, which includes computer program instructions, which, when executed by a processor, enable the processor to execute the steps of the method for performing information mining on historical change records according to various embodiments of the present invention described in the above "Exemplary Method" section of this specification.

[0122] The computer program product may be written in any combination of one or more programming languages ​​to write program code for performing the operations of the embodiments of the present invention, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0123] In addition, an embodiment of the present invention may also be a computer-readable storage medium having computer program instructions stored thereon, which, when executed by a processor, enables the processor to execute the steps of the method for information mining of historical change records according to various embodiments of the present invention described in the above “Exemplary Method” section of this specification.

[0124] The computer readable storage medium can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can include, for example, but is not limited to, a system, device or device of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination of the above. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0125] The basic principle of the present invention is described above in conjunction with specific embodiments. However, it should be pointed out that the advantages, strengths, effects, etc. mentioned in the present invention are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. must be possessed by each embodiment of the present invention. In addition, the specific details disclosed above are only for the purpose of illustration and facilitation of understanding, rather than limitation, and the above details do not limit the present invention to being implemented by adopting the above specific details.

[0126] Each embodiment in this specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the system embodiment, since it basically corresponds to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0127] The block diagrams of the devices, apparatuses, equipment, and systems involved in the present invention are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagrams. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The word "such as" used here refers to the phrase "such as but not limited to", and can be used interchangeably with it.

[0128] The method and apparatus of the present invention may be implemented in many ways. For example, the method and apparatus of the present invention may be implemented by software, hardware, firmware, or any combination of software, hardware, firmware. The above order of steps for the method is only for illustration, and the steps of the method of the present invention are not limited to the order specifically described above, unless otherwise specifically stated. In addition, in some embodiments, the present invention may also be implemented as a program recorded in a recording medium, which includes machine-readable instructions for implementing the method according to the present invention. Thus, the present invention also covers a recording medium storing a program for executing the method according to the present invention.

[0129] It should also be noted that in the apparatus, equipment and method of the present invention, each component or each step can be decomposed and / or recombined. These decompositions and / or recombinations should be regarded as equivalent schemes of the present invention. The above description of the disclosed aspects is provided to enable any technician in the field to make or use the present invention. Various modifications to these aspects are very obvious to those skilled in the art, and the general principles defined here can be applied to other aspects without departing from the scope of the present invention. Therefore, the present invention is not intended to be limited to the aspects shown here, but in accordance with the widest range consistent with the principles and novel features disclosed here.

[0130] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present invention to the forms disclosed herein. Although a number of example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A method for controlling voltage in a substation based on reactive power compensation of a photovoltaic grid-connected device, characterized in that: include: Based on the voltage fluctuation of the photovoltaic grid-connected point and the real-time available capacity of the photovoltaic grid-connected device, a segmented reactive power control strategy is formulated, wherein the segmented reactive power control strategy is used to determine the reactive power increment adjustment amount of the photovoltaic grid-connected device under different voltage fluctuations at the grid-connected point; Based on the reactive operation range of the photovoltaic grid-connected device, the segmented reactive power control strategy is modified; as well as Determine a reactive power command of the photovoltaic grid-connected device according to the segmented reactive power control strategy before correction and the segmented reactive power control strategy after correction, and issue the reactive power command to the photovoltaic grid-connected device; The segmented reactive power control strategy is: when the voltage fluctuation of the photovoltaic grid-connected point is within the regulation dead zone, the reactive power increment required to be adjusted by the photovoltaic grid-connected device is equal to zero; when the voltage fluctuation of the photovoltaic grid-connected point exceeds the regulation dead zone, the reactive power increment required to be adjusted by the photovoltaic grid-connected device is linearly adjusted based on droop control; The calculation formula of the segmented reactive power control strategy is as follows: Among them, ΔQ PV,set,t is the reactive power increment regulation of the photovoltaic grid-connected device at time t, U t is the grid connection point voltage of the photovoltaic grid-connected device at time t, U n is the nominal voltage of the power distribution system in the substation, K u is the voltage regulation coefficient, ε is the regulation dead zone; The revised segmented reactive power control strategy is: Among them, ΔQ' PV,set,t is the modified reactive increment regulation of the photovoltaic grid-connected device at time t, Q PV,set,t-1 is the reactive power instruction of the photovoltaic grid-connected device at time t-1; The reactive power instruction of the photovoltaic grid-connected device is: Q PV,set,t =Q PV,set,t-1 +ΔQ' PV,set,t Among them, Q PV,set,t is the reactive power command of the photovoltaic grid-connected device at time t, Q PV,set,t-1 is the reactive power command of the photovoltaic grid-connected device at time t-1, ΔQ' PV,set,t It is the modified reactive increment regulation value of the photovoltaic grid-connected device at time t.

2. The method according to claim 1, characterized in that Also includes: According to the real-time available capacity of the photovoltaic grid-connected device and the active output at different times, the reactive power regulation operation boundary of the photovoltaic grid-connected device is constructed, wherein the reactive power regulation operation boundary is used to indicate the correlation between the reactive power instruction of the photovoltaic grid-connected device at different times and the maximum reactive power allowed for the operation of the photovoltaic grid-connected device.

3. The method according to claim 2, characterized in that The reactive power regulation operation boundary of the photovoltaic grid-connected device is: -Q PV,max,t ≤Q PV,set,t ≤Q PV,max,t Among them, S PV is the capacity of the photovoltaic grid-connected device, P PV,t is the active output of the photovoltaic grid-connected device at time t, Q PV,set,t is the reactive power command of the photovoltaic grid-connected device at time t, Q PV,max,t It is the maximum reactive power output allowed by the photovoltaic grid-connected device at time t.

4. A voltage management device for a substation based on reactive power compensation of a photovoltaic grid-connected device, characterized in that: include: A strategy formulation module, for formulating a segmented reactive power control strategy based on the voltage fluctuation of the photovoltaic grid-connected point and the real-time available capacity of the photovoltaic grid-connected device, wherein the segmented reactive power control strategy is used to determine the reactive power increment adjustment amount of the photovoltaic grid-connected device under different voltage fluctuations at the grid-connected point; A strategy correction module, used to correct the segmented reactive power control strategy based on the reactive power operation range of the photovoltaic grid-connected device; A reactive power instruction determination module, used to determine the reactive power instruction of the photovoltaic grid-connected device according to the segmented reactive power control strategy before correction and the segmented reactive power control strategy after correction, and issue the reactive power instruction to the photovoltaic grid-connected device; The strategy formulation module is specifically used for: when the voltage fluctuation of the photovoltaic grid-connected point is in the regulation dead zone, the reactive increment that the photovoltaic grid-connected device needs to adjust is equal to zero; when the voltage fluctuation of the photovoltaic grid-connected point exceeds the regulation dead zone, linearly adjusting the reactive increment that the photovoltaic grid-connected device needs to adjust based on droop control; The strategy formulation module is specifically used to formulate the following segmented reactive power control strategy: Among them, ΔQ PV,set,t is the reactive power increment regulation of the photovoltaic grid-connected device at time t, U t is the grid connection point voltage of the photovoltaic grid-connected device at time t, U n is the nominal voltage of the power distribution system in the substation, K u is the voltage regulation coefficient, ε is the regulation dead zone; The strategy correction module is specifically used to correct and obtain the following segmented reactive power control strategy: Among them, ΔQ' PV,set,t is the modified reactive increment regulation of the photovoltaic grid-connected device at time t, Q PV,set,t-1 is the reactive power instruction of the photovoltaic grid-connected device at time t-1; The reactive power instruction determination module is specifically used to determine the following reactive power instructions: Q PV,set,t =Q PV,set,t-1 +ΔQ' PV,set,t Among them, Q PV,set,t is the reactive power command of the photovoltaic grid-connected device at time t, Q PV,set,t-1 is the reactive power command of the photovoltaic grid-connected device at time t-1, ΔQ' PV,set,t It is the modified reactive increment regulation value of the photovoltaic grid-connected device at time t.

5. The device according to claim 4, characterized in that Also includes: The reactive power regulation operation boundary construction module is used to construct the reactive power regulation operation boundary of the photovoltaic grid-connected device according to the real-time available capacity of the photovoltaic grid-connected device and the active power output at different times, wherein the reactive power regulation operation boundary is used to indicate the correlation between the reactive power instruction of the photovoltaic grid-connected device at different times and the maximum reactive power output allowed for the operation of the photovoltaic grid-connected device.

6. The device according to claim 5, characterized in that The reactive power regulation operation boundary construction module is specifically used to construct the following reactive power regulation operation boundary: -Q PV,max,t ≤Q PV,set,t ≤Q PV,max,t Among them, S PV is the capacity of the photovoltaic grid-connected device, P PV,t is the active output of the photovoltaic grid-connected device at time t, Q PV,set,t is the reactive power command of the photovoltaic grid-connected device at time t, Q PV,max,t It is the maximum reactive power output allowed by the photovoltaic grid-connected device at time t.

7. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, and the computer program is used to execute the method according to any one of claims 1 to 3.

8. An electronic device, characterized in that: The electronic device comprises: processor; a memory for storing instructions executable by the processor; The processor is used to read the executable instructions from the memory and execute the instructions to implement the method described in any one of claims 1 to 3.

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