A boundary condition and multi-dimensional margin quantification method for continuous crossing of instability of new energy

Abstract

This invention discloses a boundary condition and multidimensional margin quantification method for renewable energy continuous ride-through instability. First, an expression for the renewable energy continuous ride-through boundary is established based on unit and renewable energy parameters. Then, based on this expression, the machine-side margin and grid-side margin under the continuous ride-through boundary are calculated. This invention derives the continuous ride-through boundary for renewable energy ride-through control, obtains the machine-side margin and grid-side margin under different boundaries, and derives expressions for maximum power and line impedance for each continuous ride-through boundary, calculating different margins. This method is therefore applicable to the calculation of new transient instability phenomena dominated by renewable energy ride-through control.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and more particularly to a boundary condition for continuous crossing of instability by a new energy source and a multi-dimensional margin quantification method. Background Art

[0002] The continuous increase in installed capacity of renewable energy sources has significantly impacted the transient voltage stability of power systems. The instability phenomena of new transient voltage issues, driven by low voltage ride-through control for renewable energy sources, differ significantly from those in conventional power systems. During transients, various renewable energy sources exhibit distinct low voltage ride-through and recovery characteristics, with their active and reactive output fluctuations significantly different from those of conventional power sources. New transient instability phenomena driven by low voltage ride-through control for renewable energy sources include "sustained low voltage ride-through" and "repeated low voltage ride-through."

[0003] Under sustained low voltage ride-through (LVRT) boundary conditions, the margin of renewable energy systems is subject to new boundary constraints. Currently, conventional boundary-based models use nose-shaped points as boundaries. With the application of LVRT technology, the boundary constraints and margins of renewable energy systems will be further reduced. To account for new transient voltage instability phenomena in power systems dominated by renewable energy ride-through control, it is necessary to establish a sustained ride-through boundary suitable for renewable energy ride-through control. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a boundary condition and multi-dimensional margin quantification method for the continuous ride-through instability of new energy, derives the continuous ride-through boundary of new energy ride-through control, and obtains a comparison between the machine-side margin and the grid-side margin under different boundaries.

[0005] According to one aspect of the present invention, a method for quantifying boundary conditions and multi-dimensional margins for a new energy source to continuously cross instability is provided, including:

[0006] Based on the unit and new energy parameters, the new energy continuous crossing boundary expression is established; among which, the new energy continuous crossing boundary expression is:

[0007]

[0008] Based on the new energy continuous crossing boundary expression, calculate the machine side margin M under the continuous crossing boundary P,C and grid side margin M Z,C ; Among them, the machine side margin M under continuous crossing boundary P,C and grid side margin M Z,C The calculation formula is:

[0009]

[0010]

[0011] Where VL is the critical voltage of renewable energy continuously crossing, P is the renewable energy active output under the current operating state of the renewable energy power system equivalent model, θ is the line impedance phase angle of the renewable energy power system equivalent model, E is the voltage at the common connection point, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, and Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model.

[0012] Optionally, establishing a new energy continuous crossing boundary expression based on the unit and new energy parameters includes:

[0013] Obtain the parameters and load parameters of each unit in the system, including the voltage E at the common connection point and the voltage amplitude V at the grid connection point of the new energy equipment. t and the voltage phase angle α at the grid connection point of the new energy equipment;

[0014] Based on the acquired parameters, conventional boundary expressions are established for the unit and new energy parameters. The calculation formula is as follows:

[0015]

[0016]

[0017] Eliminating the angle α, the conventional boundary expression is simplified to:

[0018]

[0019] When the new energy source has a constant power output, Q = 0, then the conventional boundary expression is further simplified to:

[0020]

[0021] When V t To continuously cross the critical voltage V L When V t =V L , then Z th The expression is:

[0022]

[0023] Because Z th Greater than 0, when θ is in the range of 0 to 90, we have:

[0024]

[0025] Discard the meaningless negative solution and get Z th The expression is:

[0026]

[0027] Then the expression of the new energy continuous crossing boundary when the new energy operates under the continuous crossing boundary is:

[0028]

[0029] Where P is the new energy active power output under the current operating state of the new energy power system equivalent model, Q is the new energy reactive power output under the current operating state of the new energy power system equivalent model, and V t is the voltage amplitude of the grid connection point of the new energy equipment, θ is the line impedance phase angle of the equivalent model of the new energy power system, E is the voltage of the common connection point, α is the voltage phase angle of the grid connection point of the new energy equipment, Z th is the line impedance amplitude under the conventional boundary of the equivalent model of the new energy power system, V L For new energy to continue to cross the critical voltage.

[0030] Optionally, the machine side margin M under the continuous crossing boundary is calculated based on the new energy continuous crossing boundary expression. P,C and grid side margin M Z,C ,include:

[0031] Define the machine side margin M P and grid side margin M z for:

[0032]

[0033]

[0034] According to the new energy continuous crossing boundary expression, the machine side margin M is defined P and grid side margin M z , we can get the machine side margin M under continuous crossing boundary P,C and grid side margin M Z,C The calculation formula is:

[0035]

[0036]

[0037] According to the calculation formula, determine the machine side margin M under the continuous crossing boundary P,C and grid side margin M Z,C ;

[0038] Where, P max is the maximum active power output of the equivalent model of the new energy power system, Z th,max is the maximum line impedance amplitude under the conventional boundary of the equivalent model of the new energy power system, V Lis the critical voltage of renewable energy continuously crossing, P is the renewable energy active output under the current operating state of the renewable energy power system equivalent model, θ is the line impedance phase angle of the renewable energy power system equivalent model, E is the voltage at the common connection point, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, and Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model.

[0039] Optionally, the method further includes:

[0040] According to the unit and new energy parameters, the conventional boundary expression of new energy is established; among them, the conventional boundary expression of new energy is:

[0041] E 2 -2P max (1-cosθ)Z th =0;

[0042] Based on the conventional boundary expression of new energy, calculate the machine side margin M under the conventional boundary P,N and grid side margin M Z,N ; Among them, the machine side margin M under the conventional boundary P,N and grid side margin M Z,N The calculation formula is:

[0043]

[0044]

[0045] Where, E is the voltage at the common connection point, P max is the maximum active power output of the equivalent model of the new energy power system, θ is the line impedance phase angle of the equivalent model of the new energy power system, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model, and P is the new energy active output under the current operating state of the new energy power system equivalent model;

[0046] Will continue to cross the lower boundary machine side margin M P,C and grid side margin M Z,C Compared with the conventional boundary lower machine side margin M P,N and grid side margin M Z,N Make a comparison;

[0047] According to the comparison results, the machine side margin M under continuous crossing boundary is P,C and grid side margin M Z,C The calculation accuracy is evaluated.

[0048] Optionally, establishing a conventional boundary expression for new energy based on the unit and new energy parameters includes:

[0049] Obtain the parameters and load parameters of each unit in the system, including the voltage E at the common connection point and the voltage amplitude V at the grid connection point of the new energy equipment. t and the voltage phase angle α at the grid connection point of the new energy equipment;

[0050] Based on the acquired parameters, conventional boundary expressions are established for the unit and new energy parameters. The calculation formula is as follows:

[0051]

[0052]

[0053] Eliminating the angle α, the conventional boundary expression is simplified to:

[0054]

[0055] When the new energy source has a constant power output, Q = 0, then the conventional boundary expression is further simplified to:

[0056]

[0057] Then V t The two solutions of

[0058]

[0059] when When V t There is a double solution, V t The restatement of is:

[0060]

[0061] That is, the critical voltage value is

[0062]

[0063] Substitute the critical voltage value into V t In the re-solution of , we get the maximum active power output P at the critical voltage value. max and line impedance magnitude Z th The expression is:

[0064]

[0065] Solve for Z th for:

[0066]

[0067] Based on V t Resolving gives:

[0068]

[0069] Because P max Greater than 0, Z th Greater than 0, discard the meaningless negative solutions in the formula, that is:

[0070]

[0071] when When the Z value corresponding to the nose point of the PV curve is obtained th , the expression of line impedance amplitude and maximum active output is:

[0072]

[0073] Then the expression of new energy operating under conventional boundaries is:

[0074] E 2 -2P max (1-cosθ)Z th =0;

[0075] Where, P max is the maximum active power output of the equivalent model of the new energy power system, Z th,max is the maximum line impedance amplitude under the conventional boundary of the equivalent model of the new energy power system, V L is the new energy continuously crossing the critical voltage, P is the new energy active output under the current operating state of the new energy power system equivalent model, Q is the new energy reactive output under the current operating state of the new energy power system equivalent model, V t is the voltage amplitude of the grid connection point of the new energy equipment, θ is the line impedance phase angle of the equivalent model of the new energy power system, E is the voltage at the common connection point, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, and Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model.

[0076] Optionally, the conventional boundary expression of the new energy is used to calculate the machine side margin M under the conventional boundary. P,N and grid side margin M Z,N ,include:

[0077] Define the machine side margin M P and grid side margin M z for:

[0078]

[0079]

[0080] According to the conventional boundary expression of new energy, the machine side margin M is defined P and grid side margin M z, we can get the machine side margin M under the conventional boundary P,N and grid side margin M Z,N The calculation formula is:

[0081]

[0082]

[0083] Where, E is the voltage at the common connection point, P max is the maximum active power output of the equivalent model of the new energy power system, θ is the line impedance phase angle of the equivalent model of the new energy power system, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model, and P is the new energy active power output under the current operating state of the new energy power system equivalent model.

[0084] According to another aspect of the present invention, a device for quantifying boundary conditions and multi-dimensional margins for a new energy source that continuously crosses instability is provided, comprising:

[0085] The expression building module is used to build the expression for continuous crossing of the boundary of new energy according to the unit and new energy parameters; wherein, the expression for continuous crossing of the boundary of new energy is:

[0086]

[0087] Multi-dimensional margin calculation module, used to calculate the machine side margin M under the continuous crossing boundary based on the new energy continuous crossing boundary expression P,C and grid side margin M Z,C ; Among them, the machine side margin M under continuous crossing boundary P,C and grid side margin M Z,C The calculation formula is:

[0088]

[0089]

[0090] Where V L is the critical voltage of renewable energy continuously crossing, P is the renewable energy active output under the current operating state of the renewable energy power system equivalent model, θ is the line impedance phase angle of the renewable energy power system equivalent model, E is the voltage at the common connection point, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, and Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model.

[0091] 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 according to any one of the above aspects of the present invention.

[0092] 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; and the processor for reading the executable instructions from the memory and executing the instructions to implement the method described in any one of the above aspects of the present invention.

[0093] The present invention first establishes an expression for the renewable energy continuous ride-through boundary based on the generator unit and renewable energy parameters. Then, based on this expression, the generator-side and grid-side margins at the continuous ride-through boundary are calculated. The present invention derives the continuous ride-through boundary for renewable energy ride-through control, deriving the generator-side and grid-side margins for different boundaries. Furthermore, expressions for maximum power and line impedance are derived for each continuous ride-through boundary, and different margins are calculated. This method is therefore applicable to the calculation of novel transient instability phenomena dominated by renewable energy ride-through control. BRIEF DESCRIPTION OF THE DRAWINGS

[0094] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0095] Figure 1 It is a schematic diagram of the process of quantifying the boundary conditions and multi-dimensional margin of the new energy continuously crossing the instability in the embodiment of the present invention;

[0096] Figure 2 This is a comparison diagram of the maximum power of new energy and line impedance at the conventional boundary and the continuous crossing boundary in an embodiment of the present invention;

[0097] Figure 3 3. This is a comparison diagram of the margins between the conventional boundary and the continuous crossing boundary of the new energy in the embodiment of the present invention when θ=90°;

[0098] Figure 4 It is a structural diagram of an electronic device in one embodiment of the present invention. DETAILED DESCRIPTION

[0099] The embodiments of the present invention will be described in detail below. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0100] It should be understood that throughout the descriptions of all embodiments of the present invention, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly specifying the number of technical features being referred to. Thus, a feature designated "first" or "second" may explicitly or implicitly include one or more of such features. Those skilled in the art will understand the specific meanings of these terms in the present invention based on specific circumstances.

[0101] Figure 1 The flow chart of the boundary conditions and multi-dimensional margin quantification method for the continuous crossing of instability of new energy provided by the present invention is shown. Figure 1 As shown in the figure, the boundary conditions for new energy to continuously cross instability and the multi-dimensional margin quantification method include:

[0102] Step S101: Based on the unit and new energy parameters, establish a new energy continuous crossing boundary expression; wherein, the new energy continuous crossing boundary expression is:

[0103]

[0104] Step S102: Calculate the machine side margin M under the continuous crossing boundary based on the new energy continuous crossing boundary expression P,C and grid side margin M Z,C ; Among them, the machine side margin M under continuous crossing boundary P,C and grid side margin M Z,C The calculation formula is:

[0105]

[0106]

[0107] Where V L is the critical voltage of renewable energy continuously crossing, P is the renewable energy active output under the current operating state of the renewable energy power system equivalent model, θ is the line impedance phase angle of the renewable energy power system equivalent model, E is the voltage at the common connection point, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, and Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model.

[0108] Optionally, the expression for continuously crossing the boundary of new energy is established based on the parameters of the units and new energy, including: obtaining the parameters of each unit and load parameters in the system, including the voltage E at the common connection point, the voltage amplitude V at the grid connection point of the new energy equipment, and the voltage V at the grid connection point of the new energy equipment. t And the grid connection point voltage phase angle α of the new energy equipment; Based on the obtained parameters, a conventional boundary expression is established for the unit and new energy parameters. The calculation formula is as follows:

[0109]

[0110]

[0111] Eliminating the angle α, the conventional boundary expression is simplified to:

[0112]

[0113] When the new energy source has a constant power output, Q = 0, then the conventional boundary expression is further simplified to:

[0114]

[0115] When V t To continuously cross the critical voltage V L When V t =V L , then Z th The expression is:

[0116]

[0117] Because Z th Greater than 0, when θ is in the range of 0 to 90, we have:

[0118]

[0119] Discard the meaningless negative solution and get Z th The expression is:

[0120]

[0121] Then the expression of the new energy continuous crossing boundary when the new energy operates under the continuous crossing boundary is:

[0122]

[0123] Where P is the new energy active power output under the current operating state of the new energy power system equivalent model, Q is the new energy reactive power output under the current operating state of the new energy power system equivalent model, and V t is the voltage amplitude of the grid connection point of the new energy equipment, θ is the line impedance phase angle of the equivalent model of the new energy power system, E is the voltage of the common connection point, α is the voltage phase angle of the grid connection point of the new energy equipment, Z th is the line impedance amplitude under the conventional boundary of the equivalent model of the new energy power system, V L For new energy to continue to cross the critical voltage.

[0124] Optionally, the machine side margin M under the continuous crossing boundary is calculated based on the new energy continuous crossing boundary expression. P,C and grid side margin M Z,C, including: defining the machine side margin M P and grid side margin M z for:

[0125]

[0126]

[0127] According to the new energy continuous crossing boundary expression, the machine side margin M is defined P and grid side margin M z , we can get the machine side margin M under continuous crossing boundary P,C and grid side margin M Z,C The calculation formula is:

[0128]

[0129]

[0130] According to the calculation formula, determine the machine side margin M under the continuous crossing boundary P,C and grid side margin M Z,C ;

[0131] Where, P max is the maximum active power output of the equivalent model of the new energy power system, Z th,max is the maximum line impedance amplitude under the conventional boundary of the equivalent model of the new energy power system, V L is the critical voltage of renewable energy continuously crossing, P is the renewable energy active output under the current operating state of the renewable energy power system equivalent model, θ is the line impedance phase angle of the renewable energy power system equivalent model, E is the voltage at the common connection point, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, and Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model.

[0132] Optionally, the method further includes: establishing a new energy conventional boundary expression based on the unit and new energy parameters; wherein the new energy conventional boundary expression is:

[0133] E 2 -2P max (1-cosθ)Z th =0;

[0134] Based on the conventional boundary expression of new energy, calculate the machine side margin M under the conventional boundary P,N and grid side margin M Z,N ; Among them, the machine side margin M under the conventional boundary P,N and grid side margin M Z,N The calculation formula is:

[0135]

[0136] Where, E is the voltage at the common connection point, P max is the maximum active power output of the equivalent model of the new energy power system, θ is the line impedance phase angle of the equivalent model of the new energy power system, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model, and P is the new energy active output under the current operating state of the new energy power system equivalent model;

[0137] Will continue to cross the lower boundary machine side margin M P,C and grid side margin M Z,C Compared with the conventional boundary lower machine side margin M P,N and grid side margin M Z,N Compare; according to the comparison results, the machine side margin M under continuous crossing boundary P,C and grid side margin M Z,C The calculation accuracy is evaluated.

[0138] Optionally, the conventional boundary expression of new energy is established based on the parameters of the unit and new energy, including: obtaining the parameters of each unit and load parameters in the system, including the common connection point voltage E, the grid connection point voltage amplitude V of the new energy equipment t And the grid connection point voltage phase angle α of the new energy equipment; Based on the obtained parameters, a conventional boundary expression is established for the unit and new energy parameters. The calculation formula is as follows:

[0139]

[0140]

[0141] Eliminating the angle α, the conventional boundary expression is simplified to:

[0142]

[0143] When the new energy source has a constant power output, Q = 0, then the conventional boundary expression is further simplified to:

[0144]

[0145] Then V t The two solutions of

[0146]

[0147] when When V t There is a double solution, V t The restatement of is:

[0148]

[0149] That is, the critical voltage value is

[0150]

[0151] Substitute the critical voltage value into V t In the re-solution of , we get the maximum active power output P at the critical voltage value. max and line impedance magnitude Z th The expression is:

[0152]

[0153] Solve for Z th for:

[0154]

[0155] Based on V t Resolving gives:

[0156]

[0157] Because P max Greater than 0, Z th Greater than 0, discard the meaningless negative solutions in the formula, that is:

[0158]

[0159] when When the Z value corresponding to the nose point of the PV curve is obtained th , the expression of line impedance amplitude and maximum active output is:

[0160]

[0161] Then the expression of new energy operating under conventional boundaries is:

[0162] E 2 -2P max (1-cosθ)Z th =0;

[0163] Where, P max is the maximum active power output of the equivalent model of the new energy power system, Z th,max is the maximum line impedance amplitude under the conventional boundary of the equivalent model of the new energy power system, V L is the new energy continuously crossing the critical voltage, P is the new energy active output under the current operating state of the new energy power system equivalent model, Q is the new energy reactive output under the current operating state of the new energy power system equivalent model, V tis the voltage amplitude of the grid connection point of the new energy equipment, θ is the line impedance phase angle of the equivalent model of the new energy power system, E is the voltage at the common connection point, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, and Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model.

[0164] Optionally, the conventional boundary expression of the new energy is used to calculate the machine side margin M under the conventional boundary. P,N and grid side margin M Z,N ,include:

[0165] Define the machine side margin M P and grid side margin M z for:

[0166]

[0167]

[0168] According to the conventional boundary expression of new energy, the machine side margin M is defined P and grid side margin M z , we can get the machine side margin M under the conventional boundary P,N and grid side margin M Z,N The calculation formula is:

[0169]

[0170]

[0171] Where, E is the voltage at the common connection point, P max is the maximum active power output of the equivalent model of the new energy power system, θ is the line impedance phase angle of the equivalent model of the new energy power system, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model, and P is the new energy active power output under the current operating state of the new energy power system equivalent model.

[0172] In an embodiment of the present invention, Figure 2 This is a comparison chart of the maximum power of new energy and line impedance at the conventional boundary and the continuous crossing boundary. Figure 3 This is a comparison diagram of the margin between the conventional boundary of new energy and the continuous crossing boundary when θ=90°. Figure 2 and Figure 3 As shown, the machine side margin M under the continuous crossing boundary proposed by the present invention is P,C and grid side margin M Z,C The calculation accuracy is significantly better than the conventional boundary side margin M P,N and grid side margin M Z,NThe calculation accuracy of .

[0173] In summary, the present invention first establishes an expression for the renewable energy continuous ride-through boundary based on unit and renewable energy parameters. Then, based on this expression, the generator-side and grid-side margins at the continuous ride-through boundary are calculated. This invention derives the continuous ride-through boundary for renewable energy ride-through control, deriving generator-side and grid-side margins for different boundaries. Furthermore, expressions for maximum power and line impedance are derived for each continuous ride-through boundary, and different margin calculations are performed. This method is therefore applicable to the calculation of novel transient instability phenomena driven by renewable energy ride-through control.

[0174] Exemplary devices

[0175] The present invention also provides a device for quantifying boundary conditions and multi-dimensional margins for a new energy source to continuously cross instability, including:

[0176] The expression building module is used to build the expression for continuous crossing of the boundary of new energy according to the unit and new energy parameters; wherein, the expression for continuous crossing of the boundary of new energy is:

[0177]

[0178] Multi-dimensional margin calculation module, used to calculate the machine side margin M under the continuous crossing boundary based on the new energy continuous crossing boundary expression P,C and grid side margin M Z,C ; Among them, the machine side margin M under continuous crossing boundary P,C and grid side margin M Z,C The calculation formula is:

[0179]

[0180]

[0181] Where V L is the critical voltage of renewable energy continuously crossing, P is the renewable energy active output under the current operating state of the renewable energy power system equivalent model, θ is the line impedance phase angle of the renewable energy power system equivalent model, E is the voltage at the common connection point, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, and Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model.

[0182] The boundary conditions for continuous crossing of new energy through instability and the multi-dimensional margin quantification device of an embodiment of the present invention correspond to the boundary conditions for continuous crossing of new energy through instability and the multi-dimensional margin quantification method of another embodiment of the present invention, and will not be repeated here.

[0183] Exemplary electronic devices

[0184] Figure 4 This is the structure of an electronic device provided by an exemplary embodiment of the present invention. Figure 4 As shown, the electronic device 40 includes one or more processors 41 and a memory 42 .

[0185] The processor 41 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.

[0186] The memory 42 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include random access memory (RAM) and / or cache memory (cache), etc. The non-volatile memory may, for example, include read-only memory (ROM), a hard disk, a flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 41 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 further include: an input device 43 and an output device 44, and these components are interconnected via a bus system and / or other forms of connection mechanisms (not shown).

[0187] In addition, the input device 43 may also include, for example, a keyboard, a mouse, and the like.

[0188] The output device 44 can output various information to the outside. The output device 44 can include, for example, a display, a speaker, a printer, a communication network and a remote output device connected thereto.

[0189] Of course, to simplify, Figure 4 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, the electronic device may further include any other appropriate components according to specific application scenarios.

[0190] Exemplary computer program products and computer-readable storage media

[0191] 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 perform the steps of the method according to various embodiments of the present invention described in the above "Exemplary Method" section of this specification.

[0192] The computer program product may be written in any combination of one or more programming languages ​​to implement the operations of embodiments of the present invention, including object-oriented programming languages ​​such as Java, C++, and conventional procedural programming languages ​​such as C or similar programming languages. The program code may be executed entirely on the user's computing device, partially on the user's computing device, as a stand-alone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0193] 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.

[0194] 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, for example, include but is not limited to a system, system or device of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination thereof. 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 thereof.

[0195] The basic principles of the present invention have been described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, and effects mentioned in the present invention are merely illustrative and non-limiting, and should not be construed as necessarily possessed by each embodiment of the present invention. Furthermore, the specific details disclosed above are provided for illustrative purposes and to facilitate understanding, and are not intended to be limiting. These details do not necessarily limit the present invention to being implemented using these specific details.

[0196] Each embodiment in this specification is described in a progressive manner, with each embodiment focusing on its differences from the other embodiments. References to the same or similar parts between the various embodiments are sufficient. For system embodiments, since they largely correspond to method embodiments, their description is relatively simple. For relevant parts, references to the description of the method embodiments are sufficient.

[0197] The block diagrams of the devices, systems, equipment, and systems involved in the present invention are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As will be appreciated by those skilled in the art, these devices, systems, equipment, and systems can be connected, arranged, or configured in any manner. Words such as "including," "comprising," "having," and the like are open-ended words, meaning "including but not limited to," and can be used interchangeably therewith. The words "or" and "and" used herein refer to the words "and / or" and can be used interchangeably therewith, unless the context clearly indicates otherwise. The word "such as" used herein refers to the phrase "such as but not limited to," and can be used interchangeably therewith.

[0198] The method and system of the present invention may be implemented in many ways. For example, the method and system of the present invention may be implemented by software, hardware, firmware, or any combination of software, hardware, and firmware. The above sequence of steps for the method is for illustration only, and the steps of the method of the present invention are not limited to the sequence specifically described above, unless otherwise specified. 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 recording media that store programs for executing the method according to the present invention.

[0199] It should also be noted that, in the system, device 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 this field to make or use the present invention. Various modifications to these aspects will be 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 according to the widest scope consistent with the principles disclosed here and novel features.

[0200] The above description has been provided for the purpose of illustration and description. Furthermore, 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, alterations, additions, and sub-combinations thereof.

Claims

1. A boundary condition and multi-dimensional margin quantification method for a new energy source to continuously cross instability, characterized by: include: Based on the unit and new energy parameters, the new energy continuous crossing boundary expression is established; among which, the new energy continuous crossing boundary expression is: Based on the new energy continuous crossing boundary expression, calculate the machine side margin M under the continuous crossing boundary P,C and grid side margin M Z,C ; Among them, the machine side margin M under continuous crossing boundary P,C and grid side margin M Z,C The calculation formula is: Where V L is the critical voltage of renewable energy continuously crossing, P is the renewable energy active output under the current operating state of the renewable energy power system equivalent model, θ is the line impedance phase angle of the renewable energy power system equivalent model, E is the voltage at the common connection point, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, and Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model; The expression for continuously crossing the boundary of new energy is established based on the parameters of the unit and new energy, including: Obtain the parameters and load parameters of each unit in the system, including the voltage E at the common connection point and the voltage amplitude V at the grid connection point of the new energy equipment. t and the voltage phase angle α at the grid connection point of the new energy equipment; Based on the acquired parameters, conventional boundary expressions are established for the unit and new energy parameters. The calculation formula is as follows: Eliminating the angle α, the conventional boundary expression is simplified to: When the new energy source has a constant power output, Q = 0, then the conventional boundary expression is further simplified to: When V t To continuously cross the critical voltage V L When V t =V L , then Z th The expression is: Because Z th Greater than 0, when θ is in the range of 0 to 90, we have: Discard the meaningless negative solution and get Z th The expression is: Then the expression of the new energy continuous crossing boundary when the new energy operates under the continuous crossing boundary is: Where P is the new energy active power output under the current operating state of the new energy power system equivalent model, Q is the new energy reactive power output under the current operating state of the new energy power system equivalent model, and V t is the voltage amplitude of the grid connection point of the new energy equipment, θ is the line impedance phase angle of the equivalent model of the new energy power system, E is the voltage of the common connection point, α is the voltage phase angle of the grid connection point of the new energy equipment, Z th is the line impedance amplitude under the conventional boundary of the equivalent model of the new energy power system, V L For new energy to continue to cross the critical voltage.

2. The method according to claim 1, characterized in that The calculation of the machine side margin M under the continuous crossing boundary based on the new energy continuous crossing boundary expression is as follows: P,C and grid side margin M Z,C ,include: Define the machine side margin M P and grid side margin M z for: According to the new energy continuous crossing boundary expression, the machine side margin M is defined P and grid side margin M z , we can get the machine side margin M under continuous crossing boundary P,C and grid side margin M Z,C The calculation formula is: According to the calculation formula, determine the machine side margin M under the continuous crossing boundary P,C and grid side margin M Z,C ; Where, P max is the maximum active power output of the equivalent model of the new energy power system, Z th,max is the maximum line impedance amplitude under the conventional boundary of the equivalent model of the new energy power system, V L is the critical voltage of renewable energy continuously crossing, P is the renewable energy active output under the current operating state of the renewable energy power system equivalent model, θ is the line impedance phase angle of the renewable energy power system equivalent model, E is the voltage at the common connection point, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, and Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model.

3. The method according to claim 1, characterized in that Also includes: According to the unit and new energy parameters, the conventional boundary expression of new energy is established; among them, the conventional boundary expression of new energy is: E 2 -2P max (1-cosθ)Z th =0; Based on the conventional boundary expression of new energy, calculate the machine side margin M under the conventional boundary P,N and grid side margin M Z,N ; Among them, the machine side margin M under the conventional boundary P,N and grid side margin M Z,N The calculation formula is: Where, E is the voltage at the common connection point, P max is the maximum active power output of the equivalent model of the new energy power system, θ is the line impedance phase angle of the equivalent model of the new energy power system, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model, and P is the new energy active output under the current operating state of the new energy power system equivalent model; Will continue to cross the lower boundary machine side margin M P,C and grid side margin M Z,C Compared with the conventional boundary lower machine side margin M P,N and grid side margin M Z,N Make a comparison; According to the comparison results, the machine side margin M under continuous crossing boundary is P,C and grid side margin M Z,C The calculation accuracy is evaluated.

4. The method according to claim 3, characterized in that The conventional boundary expression of new energy is established based on the unit and new energy parameters, including: Obtain the parameters and load parameters of each unit in the system, including the voltage E at the common connection point and the voltage amplitude V at the grid connection point of the new energy equipment. t and the voltage phase angle α at the grid connection point of the new energy equipment; Based on the acquired parameters, conventional boundary expressions are established for the unit and new energy parameters. The calculation formula is as follows: Eliminating the angle α, the conventional boundary expression is simplified to: When the new energy source has a constant power output, Q = 0, then the conventional boundary expression is further simplified to: Then V t The two solutions of when When V t There is a double solution, V t The restatement of is: That is, the critical voltage value is Substitute the critical voltage value into V t In the re-solution of , we get the maximum active power output P at the critical voltage value. max and line impedance magnitude Z th The expression is: Solve for Z th for: Based on V t Resolving gives: Because P max Greater than 0, Z th Greater than 0, discard the meaningless negative solutions in the formula, that is: when When the Z value corresponding to the nose point of the PV curve is obtained th , the expression of line impedance amplitude and maximum active output is: Then the expression of new energy operating under conventional boundaries is: E 2 -2P max (1-cosθ)Z th =0; Where, P max is the maximum active power output of the equivalent model of the new energy power system, Z th,max is the maximum line impedance amplitude under the conventional boundary of the equivalent model of the new energy power system, V L is the new energy continuously crossing the critical voltage, P is the new energy active output under the current operating state of the new energy power system equivalent model, Q is the new energy reactive output under the current operating state of the new energy power system equivalent model, V t is the voltage amplitude of the grid connection point of the new energy equipment, θ is the line impedance phase angle of the equivalent model of the new energy power system, E is the voltage at the common connection point, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, and Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model.

5. The method according to claim 3, characterized in that Based on the conventional boundary expression of new energy, the machine side margin M under the conventional boundary is calculated. P,N and grid side margin M Z,N ,include: Define the machine side margin M P and grid side margin M z for: According to the conventional boundary expression of new energy, the machine side margin M is defined P and grid side margin M z , we can get the machine side margin M under the conventional boundary P,N and grid side margin M Z,N The calculation formula is: Where, E is the voltage at the common connection point, P max is the maximum active power output of the equivalent model of the new energy power system, θ is the line impedance phase angle of the equivalent model of the new energy power system, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model, and P is the new energy active power output under the current operating state of the new energy power system equivalent model.

6. A device for quantifying the boundary conditions and multi-dimensional margins of a new energy source that continuously crosses instability, characterized in that: include: The expression building module is used to build the expression for continuous crossing of the boundary of new energy according to the unit and new energy parameters; wherein, the expression for continuous crossing of the boundary of new energy is: Multi-dimensional margin calculation module, used to calculate the machine side margin M under the continuous crossing boundary based on the new energy continuous crossing boundary expression P,C and grid side margin M Z,C ; Among them, the machine side margin M under continuous crossing boundary P,C and grid side margin M Z,C The calculation formula is: Where V L is the critical voltage of renewable energy continuously crossing, P is the renewable energy active output under the current operating state of the renewable energy power system equivalent model, θ is the line impedance phase angle of the renewable energy power system equivalent model, E is the voltage at the common connection point, Z th is the line impedance amplitude under the conventional boundary of the new energy power system equivalent model, and Z is the line impedance amplitude under the current operating state of the new energy power system equivalent model; The expression for continuously crossing the boundary of new energy is established based on the parameters of the unit and new energy, including: Obtain the parameters and load parameters of each unit in the system, including the voltage E at the common connection point and the voltage amplitude V at the grid connection point of the new energy equipment. t and the voltage phase angle α at the grid connection point of the new energy equipment; Based on the acquired parameters, conventional boundary expressions are established for the unit and new energy parameters. The calculation formula is as follows: Eliminating the angle α, the conventional boundary expression is simplified to: When the new energy source has a constant power output, Q = 0, then the conventional boundary expression is further simplified to: When V t To continuously cross the critical voltage V L When V t =V L , then Z th The expression is: Because Z th Greater than 0, when θ is in the range of 0 to 90, we have: Discard the meaningless negative solution and get Z th The expression is: Then the expression of the new energy continuous crossing boundary when the new energy operates under the continuous crossing boundary is: Where P is the new energy active power output under the current operating state of the new energy power system equivalent model, Q is the new energy reactive power output under the current operating state of the new energy power system equivalent model, and V t is the voltage amplitude of the grid connection point of the new energy equipment, θ is the line impedance phase angle of the equivalent model of the new energy power system, E is the voltage of the common connection point, α is the voltage phase angle of the grid connection point of the new energy equipment, Z th is the line impedance amplitude under the conventional boundary of the equivalent model of the new energy power system, V L For new energy to continue to cross the critical voltage.

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 5.

8. An electronic device, characterized in that: The electronic device comprises: 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 according to any one of claims 1 to 5.

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