New energy station system strength evaluation method, system, equipment, medium and product

Abstract

The invention relates to the technical field of power systems, in particular to a new energy station system strength evaluation method, a new energy station system strength evaluation system, new energy station system strength evaluation equipment, a medium and a product. And the electric power parameters of the common connection point of the new energy station after the voltage regulation instruction is adjusted and enters the steady state are obtained, so that the system short-circuit ratio can be accurately identified, the system strength of the new energy station is evaluated by using the system short-circuit ratio, the problem that the system strength of the new energy station is difficult to evaluate in a sending end MMC constant voltage control mode is solved, and the system strength evaluation efficiency is improved. Online application can be achieved, implementation is easy, and the risk that the system is disturbed and unstable is also avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a new energy station system strength assessment method, system, equipment, medium and product. Background Art

[0002] The new power system is showing a "double high" trend of "high proportion of renewable energy" and "high proportion of power electronic equipment". The characteristics of the new power system, such as nonlinearity, time-varying, uncertainty and complexity, pose new challenges to the stable operation of the power system.

[0003] In the scenario of flexible direct current feeding into the AC power grid in the new energy scenario, the existing system strength assessment schemes mainly include harmonic injection identification scheme and active and reactive command disturbance identification scheme. Among them, the harmonic impedance injection identification scheme needs to use different harmonic frequencies and amplitudes for different AC systems to improve the identification accuracy and avoid causing the system to be disturbed and unstable, resulting in a more complicated assessment process and low efficiency. The active and reactive command disturbance identification scheme requires the flexible direct current system to actively adjust the active and reactive commands, which is difficult to achieve a good effect in the scenario where the sending-end MMC (Modular Multilevel Converter) adopts constant voltage control, resulting in low assessment accuracy. Summary of the invention

[0004] In view of this, the present invention provides a new energy station system strength assessment method, system, equipment, medium and product, which solves the technical problems that the existing new energy station system strength assessment method is complex, inefficient and has low accuracy.

[0005] A first aspect of the present invention provides a new energy station system strength assessment method, comprising:

[0006] In response to a system strength assessment request for a new energy station, obtain a current grid-side voltage value of a sending-end MMC grid-side;

[0007] Based on the preset voltage safety operation range of the new energy station grid side and the current grid side voltage value, a voltage adjustment instruction of the sending-end MMC grid side is generated, and the voltage of the sending-end MMC grid side is adjusted according to the voltage adjustment instruction;

[0008] Acquire power parameters of the common connection point of the new energy station after being adjusted by the voltage regulation instruction and entering a steady state;

[0009] Determining a system short-circuit ratio according to the power parameters of the common connection point;

[0010] The system strength of the new energy station is determined according to the system short-circuit ratio.

[0011] Preferably, the preset voltage safe operation range includes a maximum allowable value of the grid-side voltage and a minimum allowable value of the grid-side voltage;

[0012] The method of generating a voltage regulation instruction for the sending-end MMC grid side based on a preset voltage safety operation range and a current grid side voltage value of the new energy station grid side, and adjusting the voltage of the sending-end MMC grid side according to the voltage regulation instruction includes:

[0013] Determining an allowable average value of the grid-side voltage according to the maximum allowable value of the grid-side voltage and the minimum allowable value of the grid-side voltage;

[0014] Determine whether the current grid-side voltage value of the sending-end MMC grid-side is greater than the allowable average value of the grid-side voltage;

[0015] When it is determined that the current grid-side voltage value of the sending-end MMC grid-side is greater than the allowable average value of the grid-side voltage, a first grid-side voltage adjustment instruction is generated, and the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage according to the first grid-side voltage adjustment instruction, and then the current grid-side voltage value is adjusted to decrease to the minimum allowable value of the grid-side voltage;

[0016] When it is determined that the current grid-side voltage value of the sending-end MMC grid-side is not greater than the allowable average value of the grid-side voltage, a second grid-side voltage adjustment instruction is generated, and according to the second grid-side voltage adjustment instruction, the current grid-side voltage value is adjusted to first be reduced to the minimum allowable value of the grid-side voltage, and then the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage.

[0017] Preferably, the voltage regulation instruction is a first grid-side voltage regulation instruction;

[0018] The obtaining of the power parameters of the common connection point of the new energy station after being adjusted by the voltage regulation instruction and entering a steady state includes:

[0019] When the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage, a first power parameter of the common connection point after the system of the new energy station enters a steady state is obtained;

[0020] When the current grid-side voltage value is adjusted to be reduced to the minimum allowable value of the grid-side voltage, a second power parameter of the common connection point after the system of the new energy station enters a steady state is obtained.

[0021] Preferably, the voltage regulation instruction is a second grid-side voltage regulation instruction;

[0022] The obtaining of the power parameters of the common connection point of the new energy station after being adjusted by the voltage regulation instruction and entering a steady state includes:

[0023] When the current grid-side voltage value is adjusted to be reduced to the minimum allowable value of the grid-side voltage, a third power parameter of the common connection point after the system of the new energy station enters a steady state is obtained;

[0024] When the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage, a fourth power parameter of the common connection point after the system of the new energy station enters a steady state is obtained.

[0025] Preferably, the power parameters include voltage phasor measurements and current phasor measurements;

[0026] Determining the system short-circuit ratio according to the power parameters of the common connection point includes:

[0027] Determining a system equivalent impedance based on the voltage phasor measurement value and the current phasor measurement value;

[0028] The system short-circuit ratio is determined according to the system equivalent impedance.

[0029] Preferably, determining the system strength of the new energy station according to the system short-circuit ratio includes:

[0030] Based on the correlation rules between the system short-circuit ratio and the system strength, the system strength of the new energy station is determined according to the system short-circuit ratio; wherein the correlation rules between the system short-circuit ratio and the system strength are that the larger the system short-circuit ratio, the higher the system strength; and the smaller the system short-circuit ratio, the lower the system strength.

[0031] In a second aspect, the present invention further provides a new energy station system strength assessment system, comprising:

[0032] A voltage acquisition module, used to respond to a system strength assessment request for a new energy station and acquire a current grid-side voltage value of the MMC grid-side at the sending end;

[0033] A voltage regulation module, for generating a voltage regulation instruction for the sending-end MMC grid side based on a preset voltage safety operating range and a current grid side voltage value of the new energy station grid side, and adjusting the voltage of the sending-end MMC grid side according to the voltage regulation instruction;

[0034] A parameter acquisition module, used to acquire the power parameters of the common connection point of the new energy station after being adjusted by the voltage regulation instruction and entering a steady state;

[0035] A short circuit ratio determination module, used to determine the system short circuit ratio according to the power parameters of the common connection point;

[0036] A strength assessment module is used to determine the system strength of the new energy station according to the system short-circuit ratio.

[0037] In a third aspect, the present invention further provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the new energy station system strength assessment method as described in the first aspect.

[0038] In a fourth aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements the steps of the new energy station system strength assessment method as described in the first aspect.

[0039] In a fifth aspect, the present invention further provides a computer program product, comprising a computer program stored on a non-transitory computer-readable storage medium, wherein the computer program comprises program instructions, wherein when the program instructions are executed by a computer, the computer executes the steps of the new energy station system strength assessment method as described in the first aspect.

[0040] It can be seen from the above technical solutions that the present invention adjusts the voltage regulation instruction on the sending-end MMC grid side within the voltage safety operation range on the grid side of the new energy station, and obtains the power parameters of the common connection point of the new energy station after the voltage regulation instruction is adjusted and enters a steady state, so as to accurately identify the system short-circuit ratio, and use the system short-circuit ratio to evaluate the system strength of the new energy station, thereby solving the problem of the difficulty in evaluating the system strength of the new energy station under the fixed voltage control mode of the sending-end MMC. It can be applied online, is simple to implement, and avoids the risk of system instability due to disturbance. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0042] Figure 1 An application environment of a new energy station system strength assessment method provided by an embodiment of the present invention;

[0043] Figure 2 A flowchart of a new energy station system strength assessment method provided by an embodiment of the present invention;

[0044] Figure 3 A schematic diagram of an equivalent circuit provided by an embodiment of the present invention;

[0045] Figure 4 A voltage control block diagram of a sending-end MMC provided by an embodiment of the present invention;

[0046] Figure 5 A schematic diagram of the structure of a new energy station system strength assessment system provided by an embodiment of the present invention;

[0047] Figure 6 A schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0048] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] The new energy station system strength assessment method provided in the embodiment of the present application can be applied to Figure 1 In the application environment shown. Among them, each device node of the new energy station communicates with the server 102 through the network. The data storage system can store the data that the server 102 needs to process. The data storage system can be integrated on the server 102, or it can be placed on the cloud or other network servers. In response to the system strength assessment request for the new energy station, the server 102 obtains the current grid-side voltage value of the new energy station; compares the current grid-side voltage value with the preset grid-side voltage safe operating range, and generates a grid-side voltage adjustment instruction according to the comparison result; obtains the power parameters of the common connection point of the new energy station after adjustment by the grid-side voltage adjustment instruction; determines the system short-circuit ratio according to the power parameters of the common connection point; determines the system strength of the new energy station according to the system short-circuit ratio. The server 102 can be an independent physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides cloud computing services.

[0050] like Figure 2 As shown, the embodiment of the present application provides a method for evaluating the strength of a new energy station system. Figure 1 The server 102 in the example is used as an example to illustrate the method, which includes the following steps S1 to S5. Among them:

[0051] Step S1: In response to a system strength assessment request for a new energy station, a current grid-side voltage value of a sending-end MMC grid-side is obtained.

[0052] Step S2: Based on the preset voltage safety operating range of the new energy station grid side and the current grid side voltage value, generate a voltage adjustment instruction for the sending-end MMC grid side, and adjust the voltage of the sending-end MMC grid side according to the voltage adjustment instruction.

[0053] Among them, the preset voltage safe operation range includes the maximum allowable value of the grid-side voltage and the minimum allowable value of the grid-side voltage.

[0054] In step S2, based on the preset voltage safety operation range of the new energy station grid side and the current grid side voltage value, a voltage adjustment instruction of the sending-end MMC grid side is generated, and the voltage of the sending-end MMC grid side is adjusted according to the voltage adjustment instruction, including:

[0055] Step S201: Determine an allowable average value of the grid-side voltage according to a maximum allowable value of the grid-side voltage and a minimum allowable value of the grid-side voltage.

[0056] Among them, the allowable average value of the grid-side voltage is (U gmax +U gmin ) / 2.

[0057] Step S202: determine whether the current grid-side voltage value of the sending-end MMC grid-side is greater than the allowable average value of the grid-side voltage.

[0058] Step S203: When it is determined that the current grid-side voltage value on the grid-side of the sending-end MMC is greater than the allowable average value of the grid-side voltage, a first grid-side voltage adjustment instruction is generated, and the current grid-side voltage value is adjusted according to the first grid-side voltage adjustment instruction to first increase it to the maximum allowable value of the grid-side voltage, and then the current grid-side voltage value is adjusted to decrease to the minimum allowable value of the grid-side voltage.

[0059] Step S204: When it is determined that the current grid-side voltage value of the MMC grid side at the sending end is not greater than the allowable average value of the grid-side voltage, a second grid-side voltage adjustment instruction is generated, and the current grid-side voltage value is adjusted according to the second grid-side voltage adjustment instruction to first decrease to the minimum allowable value of the grid-side voltage, and then the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage.

[0060] Step S3: obtaining the power parameters of the common connection point of the new energy station after being adjusted by the voltage regulation instruction and entering a steady state.

[0061] In one example, the voltage regulation instruction is a first grid-side voltage regulation instruction.

[0062] The step S3 of obtaining the power parameters of the common connection point of the new energy station after being adjusted by the voltage regulation instruction and entering a steady state includes:

[0063] Step S301: when the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage, a first power parameter of the common connection point after the system of the new energy station enters a steady state is obtained;

[0064] Step S302: when the current grid-side voltage value is adjusted to be reduced to the minimum allowable value of the grid-side voltage, a second power parameter of the common connection point after the system of the new energy station enters a steady state is obtained.

[0065] In one example, the voltage regulation instruction is a second grid-side voltage regulation instruction.

[0066] The step S3 of obtaining the power parameters of the common connection point of the new energy station after being adjusted by the voltage regulation instruction and entering a steady state includes:

[0067] Step S311: when the current grid-side voltage value is adjusted to be reduced to the minimum allowable value of the grid-side voltage, a third power parameter of the common connection point after the system of the new energy station enters a steady state is obtained.

[0068] Step S312: when the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage, a fourth power parameter of the common connection point after the system of the new energy station enters a steady state is obtained.

[0069] The power parameters include voltage phasor measurement values ​​and current phasor measurement values.

[0070] It should be noted that in the scenario of large-scale renewable energy stations being sent out through flexible direct current, the sending-end converter station and the renewable energy station can be equivalent to the following: Figure 3 The equivalent circuit diagram shown is is the equivalent electromotive force of the AC power grid, is the equivalent impedance of the AC power grid, is the PCC (Point of Common Coupling) voltage, is the PCC point current, then It can be expressed as:

[0071]

[0072] The sending-end MMC (Modular Multilevel Converter) generally adopts constant voltage control, and its control block diagram is as follows: Figure 4 As shown, the MMC controller instruction U d,pu To adjust the grid side voltage U g (U g is the voltage phasor When adjusting the grid voltage in a short time, it is considered that the equivalent electromotive force of the AC grid There is no change, by measuring the voltage and current phasor values ​​of the PCC point in the steady state before and after the grid-side voltage changes.

[0073] For example, if U g >(U gmax+U gmin ) / 2, then by increasing the MMC controller instruction U d,pu The grid-side voltage U g = U gmax , when the system enters a steady state, obtain the voltage phasor measurement value at the PCC point and current phasor measurements After obtaining the voltage and current measurement values, by reducing the MMC controller command U d,pu The grid-side voltage U g =U gmin , when the system enters a steady state, obtain the voltage phasor measurement value at the PCC point and current phasor measurements .

[0074] When U g ≤(U gmax +U gmin ) / 2, by reducing the MMC controller instruction U d,pu The grid-side voltage U g =U gmin , when the system enters a steady state, obtain the voltage phasor measurement value at the PCC point and current phasor measurements After obtaining the voltage and current measurement values, by increasing the MMC controller command U d,pu The grid-side voltage U g = U gmax , when the system enters a steady state, obtain the voltage phasor measurement value at the PCC point and current phasor measurements .

[0075] Step S4: Determine the system short-circuit ratio according to the power parameters of the common connection point.

[0076] Wherein, determining the system short-circuit ratio according to the power parameters of the common connection point in step S4 includes:

[0077] Step S401: Determine the system equivalent impedance according to the voltage phasor measurement value and the current phasor measurement value.

[0078] Among them, the equivalent impedance can be calculated as:

[0079]

[0080] In the formula, is equal impedance.

[0081] Step S402: determine the system short-circuit ratio according to the system equivalent impedance.

[0082] Among them, the system short-circuit ratio can be calculated as:

[0083]

[0084] In the formula, UN is the rated voltage of PCC point, Zg is the equivalent impedance of the system The amplitude of is the short circuit capacity.

[0085] Step S5: determining the system strength of the new energy station according to the system short-circuit ratio.

[0086] Among them, in the scenario where new energy is fed into the AC power grid through flexible direct current, the system small disturbance stability is correlated with the short circuit ratio (SCR). The larger the SCR, the more stable the system, and the smaller the SCR, the easier the system is to become unstable. Therefore, SCR reflects the relative stability margin of the new energy feeding system and can provide a basis for grid planning and operation.

[0087] In some embodiments, based on the correlation rules between the system short circuit ratio and the system strength, the system strength of the new energy station is determined according to the system short circuit ratio; wherein, the correlation rules between the system short circuit ratio and the system strength are that the larger the system short circuit ratio, the higher the system strength; the smaller the system short circuit ratio, the lower the system strength.

[0088] It should be noted that the embodiment of the present application adjusts the voltage regulation instruction on the sending-end MMC network side within the voltage safety operating range on the network side of the new energy station, and obtains the power parameters of the common connection point of the new energy station after the voltage regulation instruction is adjusted and enters a steady state, so as to accurately identify the system short-circuit ratio, and use the system short-circuit ratio to evaluate the system strength of the new energy station, thereby solving the problem of difficulty in evaluating the system strength of the new energy station under the fixed voltage control mode of the sending-end MMC. It can be applied online, is simple to implement, and avoids the risk of system instability due to disturbance.

[0089] Based on the same inventive concept, an embodiment of the present application also provides a new energy station system strength assessment system for implementing the new energy station system strength assessment method involved above.

[0090] The implementation solution for solving the problem provided by the system is similar to the implementation solution recorded in the above method. Therefore, the specific limitations in one or more new energy station system strength assessment system embodiments provided below can be referred to the limitations on the new energy station system strength assessment method above, and will not be repeated here.

[0091] like Figure 5 As shown, the embodiment of the present application also provides a new energy station system strength assessment system, including:

[0092] The voltage acquisition module 100 is used to obtain the current grid-side voltage value of the sending-end MMC grid-side in response to a system strength assessment request for a new energy station.

[0093] The voltage regulation module 200 is used to generate a voltage regulation instruction for the sending-end MMC grid side based on the preset voltage safety operating range of the new energy station grid side and the current grid side voltage value, and adjust the voltage of the sending-end MMC grid side according to the voltage regulation instruction.

[0094] The parameter acquisition module 300 is used to acquire the power parameters of the common connection point of the new energy station after being adjusted by the voltage regulation instruction and entering a steady state.

[0095] The short circuit ratio determination module 400 is used to determine the system short circuit ratio according to the power parameters of the common connection point.

[0096] The strength evaluation module 500 is used to determine the system strength of the new energy station according to the system short-circuit ratio.

[0097] In some embodiments, the preset voltage safe operating range includes a maximum allowable grid-side voltage value and a minimum allowable grid-side voltage value.

[0098] The voltage regulation module 200 is used to determine the allowable average value of the grid-side voltage according to the maximum allowable value of the grid-side voltage and the minimum allowable value of the grid-side voltage;

[0099] Determine whether the current grid-side voltage value of the MMC grid-side at the sending end is greater than the allowable average grid-side voltage value;

[0100] When it is determined that the current grid-side voltage value of the MMC grid side at the sending end is greater than the allowable average value of the grid-side voltage, a first grid-side voltage adjustment instruction is generated, and the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage according to the first grid-side voltage adjustment instruction, and then the current grid-side voltage value is adjusted to decrease to the minimum allowable value of the grid-side voltage;

[0101] When it is determined that the current grid-side voltage value on the sending-end MMC grid side is not greater than the allowable average grid-side voltage, a second grid-side voltage adjustment instruction is generated, and the current grid-side voltage value is adjusted according to the second grid-side voltage adjustment instruction to first reduce it to the minimum allowable grid-side voltage value, and then the current grid-side voltage value is adjusted to increase it to the maximum allowable grid-side voltage value.

[0102] In some embodiments, the voltage regulation instruction is a first grid-side voltage regulation instruction;

[0103] The parameter acquisition module 300 is used to obtain the first power parameter of the common connection point after the system of the new energy station enters a steady state when the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage;

[0104] When the current grid-side voltage value is adjusted to be reduced to the minimum allowable value of the grid-side voltage, the second power parameter of the common connection point after the system of the new energy station enters a steady state is obtained.

[0105] In some embodiments, the voltage regulation instruction is a second grid-side voltage regulation instruction;

[0106] The parameter acquisition module 300 is used to obtain the third power parameter of the common connection point after the system of the new energy station enters a steady state when the current grid-side voltage value is adjusted to be reduced to the minimum allowable value of the grid-side voltage;

[0107] When the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage, the fourth power parameter of the common connection point after the system of the new energy station enters a steady state is obtained.

[0108] In some embodiments, the power parameters include voltage phasor measurements and current phasor measurements;

[0109] The short-circuit ratio determination module 400 is used to determine the system equivalent impedance according to the voltage phasor measurement value and the current phasor measurement value; and determine the system short-circuit ratio according to the system equivalent impedance.

[0110] In some embodiments, the strength assessment module 500 is used to determine the system strength of the new energy station based on the system short circuit ratio and the system strength, according to the system short circuit ratio; wherein the system short circuit ratio and the system strength The related rules are that the larger the system short circuit ratio, the higher the system strength; the smaller the system short circuit ratio, the lower the system strength.

[0111] like Figure 6 As shown, an embodiment of the present application also provides an electronic device, the electronic device 10 includes a memory 20 and a processor 30, the memory 20 stores a computer program, and when the computer program is executed by the processor 30, the processor 30 executes the steps of the new energy station system strength assessment method in the above embodiment.

[0112] An embodiment of the present application also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed, the steps of the new energy station system strength assessment method in the above embodiment are implemented.

[0113] An embodiment of the present application also provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer executes the steps of the new energy station system strength assessment method in the above-mentioned embodiment.

[0114] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described systems, electronic devices, computer storage media and computer program products can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0115] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0116] In several embodiments provided by the present invention, it is understood that each box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and a part of a module, a program segment or a code includes one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved.

[0117] In the several embodiments provided by the present invention, it should be understood that the disclosed systems, electronic devices, computer storage media, computer program products and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0118] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0119] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0120] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for executing all or part of the steps of the method described in each embodiment of the present invention through a computer device (which can be a personal computer, server, or network device, etc.). The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (full name in English: Read-Only Memory, English abbreviation: ROM), random access memory (full name in English: Random Access Memory, English abbreviation: RAM), disk or optical disk and other media that can store program codes.

[0121] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A new energy station system strength assessment method, characterized in that: include: In response to a system strength assessment request for a new energy station, obtain a current grid-side voltage value of a sending-end MMC grid-side; Based on the preset voltage safety operation range of the new energy station grid side and the current grid side voltage value, a voltage adjustment instruction of the sending-end MMC grid side is generated, and the voltage of the sending-end MMC grid side is adjusted according to the voltage adjustment instruction; Acquire power parameters of the common connection point of the new energy station after being adjusted by the voltage regulation instruction and entering a steady state; Determining a system short-circuit ratio according to the power parameters of the common connection point; The system strength of the new energy station is determined according to the system short-circuit ratio.

2. The new energy station system strength assessment method according to claim 1 is characterized in that: The preset voltage safe operation range includes the maximum allowable value of the grid-side voltage and the minimum allowable value of the grid-side voltage; The method of generating a voltage regulation instruction for the sending-end MMC grid side based on a preset voltage safety operation range and a current grid side voltage value of the new energy station grid side, and adjusting the voltage of the sending-end MMC grid side according to the voltage regulation instruction includes: Determining an allowable average value of the grid-side voltage according to the maximum allowable value of the grid-side voltage and the minimum allowable value of the grid-side voltage; Determine whether the current grid-side voltage value of the sending-end MMC grid-side is greater than the allowable average value of the grid-side voltage; When it is determined that the current grid-side voltage value of the sending-end MMC grid-side is greater than the allowable average value of the grid-side voltage, a first grid-side voltage adjustment instruction is generated, and the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage according to the first grid-side voltage adjustment instruction, and then the current grid-side voltage value is adjusted to decrease to the minimum allowable value of the grid-side voltage; When it is determined that the current grid-side voltage value of the sending-end MMC grid-side is not greater than the allowable average value of the grid-side voltage, a second grid-side voltage adjustment instruction is generated, and according to the second grid-side voltage adjustment instruction, the current grid-side voltage value is adjusted to first be reduced to the minimum allowable value of the grid-side voltage, and then the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage.

3. The new energy station system strength assessment method according to claim 2 is characterized in that: The voltage regulation instruction is a first grid-side voltage regulation instruction; The obtaining of the power parameters of the common connection point of the new energy station after being adjusted by the voltage regulation instruction and entering a steady state includes: When the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage, a first power parameter of the common connection point after the system of the new energy station enters a steady state is obtained; When the current grid-side voltage value is adjusted to be reduced to the minimum allowable value of the grid-side voltage, a second power parameter of the common connection point after the system of the new energy station enters a steady state is obtained.

4. The new energy station system strength assessment method according to claim 2 is characterized in that: The voltage regulation instruction is a second grid-side voltage regulation instruction; The obtaining of the power parameters of the common connection point of the new energy station after being adjusted by the voltage regulation instruction and entering a steady state includes: When the current grid-side voltage value is adjusted to be reduced to the minimum allowable value of the grid-side voltage, a third power parameter of the common connection point after the system of the new energy station enters a steady state is obtained; When the current grid-side voltage value is adjusted to increase to the maximum allowable value of the grid-side voltage, a fourth power parameter of the common connection point after the system of the new energy station enters a steady state is obtained.

5. The new energy station system strength assessment method according to claim 1 is characterized in that: The power parameters include voltage phasor measurements and current phasor measurements; Determining the system short-circuit ratio according to the power parameters of the common connection point includes: Determining a system equivalent impedance based on the voltage phasor measurement value and the current phasor measurement value; The system short-circuit ratio is determined according to the system equivalent impedance.

6. The new energy station system strength assessment method according to claim 1 is characterized in that: Determining the system strength of the new energy station according to the system short-circuit ratio includes: Based on the correlation rules between the system short-circuit ratio and the system strength, the system strength of the new energy station is determined according to the system short-circuit ratio; wherein the correlation rules between the system short-circuit ratio and the system strength are that the larger the system short-circuit ratio, the higher the system strength; and the smaller the system short-circuit ratio, the lower the system strength.

7. A new energy station system strength assessment system, characterized in that: include: A voltage acquisition module, used to respond to a system strength assessment request for a new energy station and acquire a current grid-side voltage value of the MMC grid-side at the sending end; A voltage regulation module, for generating a voltage regulation instruction for the sending-end MMC grid side based on a preset voltage safety operating range and a current grid side voltage value of the new energy station grid side, and adjusting the voltage of the sending-end MMC grid side according to the voltage regulation instruction; A parameter acquisition module, used to acquire the power parameters of the common connection point of the new energy station after being adjusted by the voltage regulation instruction and entering a steady state; A short circuit ratio determination module, used to determine the system short circuit ratio according to the power parameters of the common connection point; A strength assessment module is used to determine the system strength of the new energy station according to the system short-circuit ratio.

8. An electronic device, characterized in that: The electronic device includes a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the steps of the new energy station system strength assessment method as described in any one of claims 1-6.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed, the steps of the new energy station system strength assessment method as described in any one of claims 1 to 6 are implemented.

10. A computer program product, characterized in that The computer program product includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions, wherein when the program instructions are executed by a computer, the computer executes the steps of the new energy station system strength assessment method as described in any one of claims 1-6.

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