CN117977616B - Voltage support control method and device, computer equipment and medium during power grid fault - Google Patents

Abstract

The invention relates to the technical field of new energy power generation, and discloses a voltage support control method, a device, computer equipment and a medium for power grid faults, wherein after the power grid faults, the method considers the second reactive current margin of a generator set in a new energy power station when generating a voltage control instruction, and subsequently, when the voltage support control of the power grid is carried out, the reactive current output by the new energy generator set is utilized, thereby effectively reducing the demand for the reactive current output by an energy storage system, the method and the system have the advantages that the requirement on capacity configuration of the energy storage system is reduced, the voltage support control is carried out on the power grid through cooperation among the generator set, the reactive compensation device and the energy storage system in the new energy power station, the stability of the power system is improved, and the problem that when the maximum reactive current output by the reactive compensation device is insufficient to provide support for grid connection points in the related technology, the reactive current is only provided by the energy storage system, the capacity configuration requirement of the energy storage system is high, and electric energy waste is caused is solved.

Description

Voltage support control method and device, computer equipment and medium during power grid fault

Technical Field

The invention relates to the technical field of new energy power generation, in particular to a voltage support control method, a device, computer equipment and a medium for power grid faults.

Background

Along with the continuous improvement of the permeability of new energy power generation, the power output of the new energy source is required to be kept stable, and the grid-connected point voltage is required to be responded to and supported during the fault ride-through period of the power grid system, so that the system stability is ensured.

At present, when a power grid system is in fault ride-through, a new energy power station generally outputs reactive current through cooperation of a reactive power compensation device (STATIC VAR Generator, SVG) and an energy storage system, and provides voltage support for grid-connected points. In the coordination control, the reactive power compensation device outputs reactive current to provide voltage support for the grid-connected point, and when the maximum reactive current output by the reactive power compensation device is insufficient to provide support for the grid-connected point, the energy storage system and the reactive power compensation device jointly output reactive current to provide voltage support for the grid-connected point. However, the energy storage system is an active output device, and when the maximum reactive current output by the reactive compensation device is insufficient to provide support for the grid-connected point, the energy storage system only provides reactive current, so that the capacity configuration requirement of the energy storage system is high, and the waste of electric energy is caused.

Disclosure of Invention

In view of the above, the invention provides a method, a device, a computer device and a medium for controlling voltage support in case of power grid faults, so as to solve the problems that when the maximum reactive current output by a reactive compensation device is insufficient to provide support for grid connection points, the reactive current is only provided by an energy storage system, the capacity configuration requirement of the energy storage system is higher, and electric energy waste is caused.

The voltage support control method comprises the steps of obtaining grid-connected point voltage of a new energy power station, reactive power of a reactive compensation device, active power of a new energy power generating set and active power of an energy storage system when grid faults are monitored, determining reactive current to be provided by the new energy power station according to the voltage of the grid-connected point of the new energy power station, determining a first reactive current margin of the reactive compensation device according to the reactive power of the reactive compensation device, determining a second reactive current margin of the new energy power generating set according to the active power of the new energy power generating set, determining a third reactive current margin of the energy storage system according to the active power of the energy storage system, generating a voltage control instruction according to the first reactive current margin, the second reactive current margin, the third reactive current margin and the reactive current to be provided by the new energy power generating set, and the energy storage system, wherein the voltage control instruction is used for controlling the reactive compensation device, the new energy power generating set and the energy storage system to provide reactive current to the grid.

According to the voltage support control method for the power grid fault, reactive current to be provided by the new energy power station is calculated based on the grid-connected point voltage of the new energy power station when the power grid fault occurs, and a voltage control instruction is generated based on the first reactive current margin of the reactive compensation device, the third reactive power margin of the energy storage system, the second reactive current margin of the new energy power generator set and the reactive current to be provided by the new energy power station, and is used for controlling the reactive compensation device, the new energy power generator set and the energy storage system to provide reactive current for the power grid. According to the method provided by the invention, after the power grid fails, the second reactive current allowance of the generator set in the new energy power station is considered when the voltage control instruction is generated, and then when the voltage support control of the power grid is carried out, the new energy generator set is utilized to output reactive current, so that the requirement on the output reactive current of the energy storage system is effectively reduced, the requirement on the capacity configuration of the energy storage system is further reduced, the voltage support control of the power grid is carried out through the cooperation among the generator set, the reactive compensation device and the energy storage system in the new energy power station, the stability of the power system is improved, and the problem that the energy storage system only provides reactive current when the maximum reactive current output by the reactive compensation device is insufficient to provide support for the grid connection point in the related art is solved, the capacity configuration requirement of the energy storage system is higher, and the electric energy waste is caused.

In an alternative embodiment, before the step of acquiring the grid-connected point voltage of the new energy power station, the reactive power of the reactive compensation device, the active power of the new energy generator set and the active power of the energy storage system when the grid fault is monitored, the method further comprises the steps of acquiring the grid-connected point actual measurement voltage and the grid-connected point rated voltage of the new energy power station, judging whether the grid is faulty or not based on the grid-connected point actual measurement voltage, the grid-connected point rated voltage and the preset voltage fluctuation range of the new energy power station, and obtaining a judging result.

According to the method provided by the alternative embodiment, whether the power grid fails or not is judged through the actual measured voltage of the grid connection point, the rated voltage of the grid connection point and the preset voltage fluctuation range of the new energy power station, so that the judging result of the power grid failure can be more accurate.

In an alternative embodiment, the method comprises the steps of obtaining rated current values of grid connection points of the new energy power station, determining a per unit value of voltage of the grid connection points of the new energy power station based on actual measurement voltage of the grid connection points of the new energy power station and rated voltage of the grid connection points, and determining reactive current to be provided by the new energy power station based on the per unit value of voltage of the grid connection points of the new energy power station and the rated current values of the grid connection points of the new energy power station.

The reactive current to be provided by the new energy power station in the power grid fault can be accurately obtained by the method provided by the alternative embodiment.

In an alternative embodiment, the step of determining the first reactive current margin of the reactive compensation device according to the reactive power of the reactive compensation device comprises the steps of obtaining the rated capacity of the reactive compensation device, determining the reactive power margin of the reactive compensation device based on the rated capacity of the reactive compensation device, the reactive power of the reactive compensation device and the reactive current to be provided by the new energy power station, and determining the first reactive current margin based on the reactive power margin of the reactive compensation device and the grid-connected point voltage of the new energy power station.

In an alternative embodiment, the new energy power station comprises a plurality of new energy power generating sets, and the step of determining a second reactive current margin of the new energy power generating sets according to active power of the new energy power generating sets comprises the steps of obtaining maximum apparent power corresponding to different power generating sets respectively, determining reactive power margins of the corresponding new energy power generating sets based on the active power and the maximum apparent power of each new energy power generating set, determining total reactive power margins of the different new energy power generating sets, and determining the second reactive current margin based on the total reactive power margins of the different new energy power generating sets and grid-connected point voltage of the new energy power station.

In an alternative embodiment, the energy storage system comprises a plurality of energy storage inverters, and the step of determining a third reactive current margin of the energy storage system according to the active power of the energy storage system comprises the steps of obtaining the active power and the maximum apparent power output by each energy storage inverter in the energy storage system, determining the reactive power margin of the corresponding energy storage inverter based on the active power and the maximum apparent power output by each energy storage inverter, determining the total reactive power margin of different energy storage inverters, and determining the third reactive current margin based on the total reactive power margin of different energy storage inverters and the grid-connected point voltage of the new energy power station.

In an alternative implementation mode, the step of generating a voltage control instruction according to the first reactive current allowance, the second reactive current allowance, the third reactive current allowance and reactive current to be provided by the new energy power station comprises the steps of comparing the reactive current to be provided by the new energy power station with the sum of the first reactive current allowance and the third reactive current allowance to obtain a comparison result, determining a first reactive current to be output of the reactive compensation device and a second reactive current to be output of the energy storage system when the reactive current to be provided by the new energy power station is smaller than or equal to the sum of the first reactive current allowance and the third reactive current allowance, generating a first control instruction according to the first reactive current to be output and the second reactive current to be output, wherein the first control instruction is used for controlling the reactive compensation device and the energy storage system to provide reactive current to a power grid, determining a third reactive current to be output of the reactive compensation device, a fourth reactive current to be output of the energy storage system and a fifth reactive current to be output of the new energy power generation unit when the reactive current to be provided by the new energy power station is larger than the sum of the first reactive current allowance and the third reactive current allowance, and the fifth reactive current to be output of the new energy power generation unit, and the reactive current to be output of the reactive power generation system is used for generating the reactive current instruction to the power compensation device and the fourth reactive current to be output to the power control system.

In an alternative implementation mode, the step of generating a voltage control instruction according to the first reactive current margin, the second reactive current margin, the third reactive current margin and reactive current to be provided by the new energy power station further comprises the steps of controlling active power of the energy storage system to be reduced to meet a first preset condition when the sum of the first reactive current margin, the second reactive current margin and the third reactive current margin is smaller than reactive current to be provided by the new energy power station, obtaining a fourth reactive current margin of the energy storage system, generating a third control instruction when the sum of the first reactive current margin, the second reactive current margin and the fourth reactive current margin is larger than or equal to reactive current to be provided by the new energy power station, controlling the active power of the new energy power generator to be met by the second preset condition when the sum of the first reactive current margin, the second reactive current margin and the fourth reactive current margin is smaller than reactive current to be provided by the new energy power station, and generating a third control instruction for controlling the reactive compensation device, the new energy power generator and the energy storage system to provide reactive current to the power grid when the sum of the first reactive current margin, the second reactive current margin and the fourth reactive current margin is smaller than reactive current to be provided by the new energy power station, and the fourth reactive current instruction to be provided by the new energy power generator is larger than or equal to the fourth reactive current instruction to the fourth reactive current to be provided by the new energy power station.

The invention provides a voltage support control device during power grid faults, which is used for obtaining grid-connected point voltage of a new energy power station, reactive power of a reactive compensation device, active power of a new energy power generating set and active power of an energy storage system when the power grid faults are monitored, a first determining module used for determining reactive current to be provided by the new energy power station according to the voltage of the grid-connected point of the new energy power station, a second determining module used for determining a first reactive current margin of the reactive compensation device according to the reactive power of the reactive compensation device, a third determining module used for determining a second reactive current margin of the new energy power generating set according to the active power of the new energy power generating set, a fourth determining module used for determining a third reactive current margin of the energy storage system according to the active power of the energy storage system, and a command generating module used for generating a voltage control command according to the first reactive current margin, the second reactive current margin, the third reactive current margin and the reactive current to be provided by the new energy power generating set, and the energy storage system.

In an alternative implementation mode, the acquisition module comprises a first acquisition sub-module and a judgment sub-module, wherein the first acquisition sub-module is used for acquiring the actual measurement voltage of the grid connection point and the rated voltage of the grid connection point of the new energy power station, and the judgment sub-module is used for judging whether the power grid fails or not based on the actual measurement voltage of the grid connection point, the rated voltage of the grid connection point and the preset voltage fluctuation range of the new energy power station, so that a judgment result is obtained.

In an alternative implementation mode, the first determining module comprises a second obtaining submodule, a first determining submodule and a second determining submodule, wherein the second obtaining submodule is used for obtaining rated current values of grid connection points of the new energy power station, the first determining submodule is used for determining a per unit value of voltage of the grid connection points of the new energy power station based on actual measurement voltage of the grid connection points of the new energy power station and rated voltage of the grid connection points of the new energy power station, and the second determining submodule is used for determining reactive current to be provided by the new energy power station based on the per unit value of voltage of the grid connection points of the energy power station and the rated current values of the grid connection points of the new energy power station.

In an alternative implementation mode, the second determining module comprises a third obtaining submodule, a third determining submodule and a fourth determining submodule, wherein the third obtaining submodule is used for obtaining rated capacity of the reactive power compensation device, the third determining submodule is used for determining reactive power allowance of the reactive power compensation device based on the rated capacity of the reactive power compensation device, reactive power of the reactive power compensation device and reactive current to be provided by the new energy power station, and the fourth determining submodule is used for determining the first reactive current allowance based on the reactive power allowance of the reactive power compensation device and grid-connected point voltage of the new energy power station.

In an alternative implementation mode, the third determining module comprises a fourth obtaining submodule, a fifth determining submodule, a sixth determining submodule and a seventh determining submodule, wherein the fourth obtaining submodule is used for obtaining maximum apparent power respectively corresponding to different power generating sets, the fifth determining submodule is used for determining reactive power allowance of the corresponding new energy power generating sets based on active power and the maximum apparent power of each new energy power generating set, the sixth determining submodule is used for determining total reactive power allowance of the different new energy power generating sets, and the seventh determining submodule is used for determining the second reactive current allowance based on the total reactive power allowance of the different new energy power generating sets and grid-connected point voltage of the new energy power station.

In a third aspect, the present invention provides a computer device, including a memory and a processor, where the memory and the processor are communicatively connected to each other, and the memory stores computer instructions, and the processor executes the computer instructions, so as to execute the voltage support control method during grid faults in the first aspect or any embodiment corresponding to the first aspect.

In a fourth aspect, the present invention provides a computer-readable storage medium having stored thereon computer instructions for causing a computer to execute the grid fault-time voltage support control method of the first aspect or any one of its corresponding embodiments.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is a flow chart of a method for voltage support control at grid failure according to an embodiment of the invention;

FIG. 2 is a flow chart of another method for voltage support control at grid failure according to an embodiment of the invention;

FIG. 3 is a flow chart of a voltage support control method at a further grid fault according to an embodiment of the invention;

FIG. 4 is a block diagram of a voltage support control apparatus at grid failure according to an embodiment of the present invention;

fig. 5 is a schematic diagram of a hardware structure of a computer device according to an embodiment of the present invention.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

In the related art, when a power grid system is in fault ride-through, a new energy power station generally outputs reactive current through cooperation of a reactive power compensation device (STATIC VAR Generator, SVG) and an energy storage system, and provides voltage support for grid connection points. In the coordination control, the reactive power compensation device outputs reactive current to provide voltage support for the grid-connected point, and when the maximum reactive current output by the reactive power compensation device is insufficient to provide support for the grid-connected point, the energy storage system and the reactive power compensation device jointly output reactive current to provide voltage support for the grid-connected point. However, the energy storage system is an active output device, and when the maximum reactive current output by the reactive compensation device is insufficient to provide support for the grid-connected point, the energy storage system only provides reactive current, so that the capacity configuration requirement of the energy storage system is high, and the waste of electric energy is caused.

In view of the above, the present invention provides a voltage support control method for a power grid fault, which can be applied to a server, and can implement voltage support control for the power grid when the power grid fault occurs. According to the method provided by the invention, after the power grid fails, the second reactive current allowance of the generator set in the new energy power station is considered when the voltage control instruction is generated, and the reactive current output by the new energy generator set is utilized when the voltage support control of the power grid is carried out subsequently, so that the requirement on the output reactive current of the energy storage system is effectively reduced, the requirement on the capacity configuration of the energy storage system is further reduced, the voltage support control of the power grid is carried out through the cooperation among the generator set, the reactive compensation device and the energy storage system in the new energy power station, the stability of the power system is improved, and the problem that the energy storage system only provides reactive current when the maximum reactive current output by the reactive compensation device is insufficient to provide support for the grid connection point in the related art is solved, the capacity configuration requirement of the energy storage system is higher, and the electric energy waste is caused.

According to an embodiment of the present invention, there is provided an embodiment of a voltage support control method at the time of a grid fault, it should be noted that the steps shown in the flowchart of the drawings may be performed in a computer system such as a set of computer executable instructions, and that although a logical sequence is shown in the flowchart, in some cases the steps shown or described may be performed in a different order than here.

In this embodiment, a method for controlling voltage support during power grid failure is provided, which may be used in the server described above, and fig. 1 is a flowchart of a method for controlling voltage support during power grid failure according to an embodiment of the present invention, as shown in fig. 1, where the flowchart includes the following steps:

And step S101, when the grid fault is monitored, acquiring the grid-connected point voltage of the new energy power station, the reactive power of the reactive compensation device, the active power of the new energy generator set and the active power of the energy storage system.

The power grid may be any power grid requiring voltage support control, and the power grid is connected to a new energy power station, where the new energy power station includes a plurality of generator sets. Reactive compensation devices may include, but are not limited to, a static var compensator (STATIC VAR Generator, SVG), which is an electronic reactive compensation device that utilizes high power semiconductor devices to control capacitors or inductors to generate or absorb reactive power. The reactive power of the reactive power compensation device, the active power of the new energy generator set and the active power of the energy storage system are obtained through monitoring by a preset power monitoring device.

And step S102, determining reactive current to be provided by the new energy power station according to the voltage of the grid connection point of the new energy power station.

In an exemplary embodiment of the present application, the reactive current to be provided by the new energy power station may be calculated based on the grid-connected point of the new energy power station and the voltage of the grid-connected point when the grid-connected point is operating normally.

And step S103, determining a first active current margin of the reactive compensation device according to the reactive power of the reactive compensation device.

The first reactive current margin is used to characterize the output capacity of the reactive power compensator, based on which the reactive current margin of the reactive compensator can be calculated.

And step S104, determining a second reactive current margin of the new energy generator set according to the active power of the new energy generator set.

The new energy power station can comprise a plurality of generator sets, the second reactive current margin is the sum of reactive power margins of all the generator sets in the new energy power station, the corresponding reactive power margin is calculated based on the active power of each generator set, and finally the sum of reactive power margins of all the generator sets in the new energy power station is obtained.

Step S105, determining a third reactive current margin of the energy storage system according to the active power of the energy storage system.

Illustratively, in the embodiment of the present application, the third reactive current margin is a total reactive current margin of the energy storage system in the new energy power station.

And step S106, generating a voltage control instruction according to the first reactive current margin, the second reactive current margin, the third reactive current margin and reactive current to be provided by the new energy power station, wherein the voltage control instruction is used for controlling the reactive compensation device, the new energy power generator set and the energy storage system to provide reactive current for the power grid.

In an embodiment of the application, a voltage control instruction is generated according to the first reactive current margin, the second reactive current margin, the third reactive current margin and reactive current to be provided by the new energy power station, and the voltage control instruction is used for carrying out coordinated control on the reactive current output by the reactive compensation device, the new energy power generator set and the energy storage system, so as to provide reactive current for the power grid, thereby realizing voltage support control on the power grid.

According to the voltage support control method for the power grid fault, after the power grid fault, the second reactive current allowance of the generator set in the new energy power station is considered when a voltage control instruction is generated, and the reactive current output by the new energy generator set is utilized when the voltage support control of the power grid is carried out subsequently, so that the requirement for the output reactive current of the energy storage system is effectively reduced, the requirement for capacity configuration of the energy storage system is further reduced, the voltage support control is carried out on the power grid through cooperation among the generator set, the reactive compensation device and the energy storage system in the new energy power station, the stability of the power system is improved, and the problem that the energy storage system only provides reactive current when the maximum reactive current output by the reactive compensation device is insufficient for providing support for grid connection points in the related art, the capacity configuration requirement of the energy storage system is high, and electric energy waste is caused is solved.

In this embodiment, a method for controlling voltage support during power grid failure is provided, which may be used in the server described above, and fig. 2 is a flowchart of a method for controlling voltage support during power grid failure according to an embodiment of the present invention, as shown in fig. 2, where the flowchart includes the following steps:

Step S201, when a grid fault is monitored, grid-connected point voltage of the new energy power station, reactive power of the reactive compensation device, active power of the new energy generator set and active power of the energy storage system are obtained. Please refer to step S101 in the embodiment shown in fig. 1 in detail, which is not described herein.

In some alternative embodiments, before step S201, the method further includes the following steps:

Step a1, obtaining actual measurement voltage of a grid connection point and rated voltage of the grid connection point of the new energy power station.

And a step a2, judging whether the power grid fails or not based on the actual measured voltage of the grid connection point of the new energy power station, the rated voltage of the grid connection point and the preset voltage fluctuation range, and obtaining a judging result.

In the embodiment of the application, the voltage of the grid-connected point of the new energy power station can be represented by U _g, the rated voltage of the grid-connected point can be represented by U _N, and when 0.2×U _N≤U_g≤0.9×U_N or 1.1×U _N≤U_g≤1.3×U_N, the system enters a fault ride-through process, so that the power grid can be determined to be faulty.

Step S202, determining reactive current to be provided by the new energy power station according to the voltage of the grid connection point of the new energy power station.

Specifically, the step S202 includes:

And step S2021, obtaining a rated current value of the grid-connected point of the new energy power station.

For example, in the embodiment of the present application, the rated current value of the grid-connected point of the new energy power station may be represented by I _N.

And step S2022, determining the voltage per unit value of the grid-connected point of the new energy power station based on the actual measured voltage of the grid-connected point of the new energy power station and the rated voltage of the grid-connected point.

The voltage per unit value of the grid-connected point of the new energy power station is the ratio of the measured voltage of the grid-connected point to the rated voltage of the grid-connected point, and in the embodiment of the application, the voltage per unit value of the grid-connected point of the new energy power station is represented by U _t, wherein,

And step S2023, determining reactive current to be provided by the new energy power station based on the per unit value of the voltage of the grid-connected point of the energy power station and the rated current value of the grid-connected point of the new energy power station.

In an exemplary embodiment of the present application, the reactive current to be provided by the new energy power station is determined by the following formula (1):

Wherein delta I _t is reactive current to be provided by the new energy power station, and can also be called dynamic reactive current increment of the new energy power station, and K ₁、K₂ is dynamic reactive current proportionality coefficient.

Step S203, determining a first active current margin of the reactive compensation device according to the reactive power of the reactive compensation device.

Specifically, the step S203 includes:

step S2031, obtaining a rated capacity of the reactive compensation device.

Illustratively, in the embodiment of the present application, the rated capacity of the reactive compensation device may be obtained through a capacity specification in the attribute information of the reactive compensation device.

And step S2032, determining the reactive power margin of the reactive compensation device based on the rated capacity of the reactive compensation device, the reactive power of the reactive compensation device and the reactive current to be provided by the new energy power station.

Illustratively, in the embodiment of the present application, the reactive power margin of the reactive compensation device may be determined by the following formula (2):

Wherein S _svg is the rated capacity of the reactive power compensator SVG, Q _svg,r is the reactive power of the reactive power compensator SVG, and Q _svg,res is the reactive power margin of the reactive power compensator.

Step S2033, determining a first active current margin based on the reactive power margin of the reactive compensation device and the grid-connected point voltage of the new energy power station.

Illustratively, in the embodiment of the present application, the first passive current margin may be calculated by the following formula (3):

wherein I _svg,res is a first active current margin, and the meanings of the remaining variables are referred to above, and are not described herein.

And S204, determining a second reactive current margin of the new energy generator set according to the active power of the new energy generator set.

Specifically, the step S204 includes:

step S2041, obtaining maximum apparent power respectively corresponding to different generator sets.

For example, in the embodiment of the present application, the maximum apparent power corresponding to each of the different generator sets may be represented by S _w,g, and S _w,g represents the maximum apparent power of the g-th generator set.

And step S2042, determining the reactive power margin of the corresponding new energy generator set based on the active power and the maximum apparent power of each new energy generator set.

Illustratively, in the embodiment of the present application, the reactive power margin of the new energy generator set may be calculated by the following formula (4):

Wherein Q _w,res,g represents the reactive power margin of the g-th generator set, and P _w,g represents the active power of the g-th generator set.

And step S2043, determining the total reactive power margin of the different new energy generator sets.

Illustratively, in an embodiment of the present application, the total reactive power margin of different new energy generator sets may be determined by the following equation (5):

wherein, Q _w,res is the total reactive power allowance of different new energy generating sets, g is the identification of the new energy generating sets, and n is the number of the new energy generating sets.

And step S2044, determining a second reactive current margin based on the total reactive power margin of the different new energy power generating sets and the grid-connected point voltage of the new energy power station.

Illustratively, in an embodiment of the present application, the second reactive current margin may be determined by the following equation (6):

Wherein I _w,res is the second reactive current margin, and the meanings of the remaining variables are referred to above, and are not described herein.

Step S205, determining a third reactive current margin of the energy storage system according to the active power of the energy storage system.

And S206, generating a voltage control instruction according to the first reactive current margin, the second reactive current margin, the third reactive current margin and reactive current to be provided by the new energy power station, wherein the voltage control instruction is used for controlling the reactive compensation device, the new energy power generator set and the energy storage system to provide reactive current for the power grid.

In this embodiment, a method for controlling voltage support during power grid failure is provided, which may be used in the server described above, and fig. 3 is a flowchart of a method for controlling voltage support during power grid failure according to an embodiment of the present invention, as shown in fig. 3, where the flowchart includes the following steps:

Step S301, when a grid fault is monitored, acquiring grid-connected point voltage of a new energy power station, reactive power of a reactive compensation device, active power of a new energy generator set and active power of an energy storage system. Please refer to step S101 in the embodiment shown in fig. 1 in detail, which is not described herein.

And step S302, determining reactive current to be provided by the new energy power station according to the voltage of the grid connection point of the new energy power station.

Step S303, determining a first active current margin of the reactive compensation device according to the reactive power of the reactive compensation device.

And step S304, determining a second reactive current margin of the new energy generator set according to the active power of the new energy generator set.

Step S305, determining a third reactive current margin of the energy storage system according to the active power of the energy storage system.

Specifically, the energy storage system includes a plurality of energy storage inverters, and the step S305 includes:

step S3051, obtaining active power and maximum apparent power output by each energy storage inverter in the energy storage system.

Illustratively, in the embodiment of the present application, the maximum apparent power of the jth energy storage inverter may be represented by S _BS,j, and the active power output by the jth energy storage inverter may be represented by P _BS,j.

Step S3052, determining a reactive power margin of the corresponding energy storage inverter based on the active power and the maximum apparent power output by each energy storage inverter.

Illustratively, in an embodiment of the present application, the reactive power margin of the energy storage inverter may be determined by the following equation (7):

Wherein Q _BS,res,j is the reactive power margin of the jth energy storage inverter, and the meanings of the remaining variables are referred to above, and are not described herein.

Step S3053, determining the total reactive power margin of the different energy storage inverters.

Illustratively, in an embodiment of the present application, the total reactive power margin may be determined by the following equation (8):

Wherein Q _BS,res is the total reactive power margin, and m is the number of inverters of the energy storage system.

And step S3054, determining a third reactive current margin based on the total reactive power margin of different energy storage inverters and the grid-connected point voltage of the new energy power station.

Illustratively, in an embodiment of the present application, the third reactive current margin may be determined by the following equation (9):

wherein I _BS,res is a third reactive current margin, and the meaning of the variable is described above, and will not be described herein.

And step S306, generating a voltage control instruction according to the first reactive current margin, the second reactive current margin, the third reactive current margin and reactive current to be provided by the new energy power station, wherein the voltage control instruction is used for controlling the reactive compensation device, the new energy power generator set and the energy storage system to provide reactive current for the power grid.

Specifically, the step S306 includes:

And step 3061, comparing the reactive current to be provided by the new energy power station with the sum of the first reactive current allowance and the third reactive current allowance to obtain a comparison result.

In the embodiment of the application, when I _svg,res≥|ΔI_t |, the first reactive current margin of the SVG meets the dynamic reactive current requirement of the power grid, and at the moment, the reactive current is provided for the power grid only by utilizing the SVG based on the formula (1).

And step 3062, when the reactive current to be provided by the new energy power station is smaller than or equal to the sum of the first reactive current allowance and the third reactive current allowance, determining the first reactive current to be output of the reactive compensation device and the second reactive current to be output of the energy storage system.

Illustratively, in the embodiment of the present application, when I _svg,res≥|ΔI_t, the first reactive current margin of the SVG meets the dynamic reactive current requirement of the power grid, where only the SVG is needed to provide reactive current to the power grid based on equation (1). When I _svg,res<|ΔI_t is, SVG reactive power margin does not meet the dynamic reactive current requirement of the power grid, and the reactive current margin of energy storage is needed to be utilized at the moment. When I _svg,res+I_BS,res≥|ΔI_t |, SVG and energy storage reactive margin meet the dynamic reactive current requirement of the power grid. At this time, the SVG supplies reactive current (first reactive current to be outputted) with the maximum margin, i.e.The reactive current provided by the energy storage system (the second reactive current to be output) is I _BS＝ΔI_t-I_svg.

And step 3063, generating a first control instruction according to the first reactive current to be output and the second reactive current to be output, wherein the first control instruction is used for controlling the reactive compensation device and the energy storage system to provide reactive current for the power grid.

And step 3064, when the reactive current to be provided by the new energy power station is larger than the sum of the first reactive current margin and the third reactive current margin, determining the third reactive current to be output of the reactive compensation device, the fourth reactive current to be output of the energy storage system and the fifth reactive current to be output of the new energy power generator set.

Illustratively, in the embodiment of the present application, when I _svg,res+I_BS,res<|ΔI_t, the total reactive current margin of the SVG and the energy storage system does not meet the dynamic reactive current requirement of the power grid, and the reactive current margin of the new energy generator set needs to be utilized at this time. The total reactive current margin of the new energy power station is I _res＝I_svg,res+I_w,res+I_BS,res, and when I _res≥|ΔI_t |, the total reactive current margin of the new energy power station meets the dynamic reactive current requirement of the power grid. At this time, the SVG still provides reactive current (third to-be-output reactive current) according to the maximum margin, i.e.The energy storage system provides reactive current (fourth to be output reactive current) according to the maximum margin, i.eReactive current (fifth reactive current to be output) provided by a generator set in the new energy power station is I _w＝ΔI_t-I_svg-I_BS.

And step 3065, generating a second control instruction based on the third reactive current to be output, the fourth reactive current to be output and the fifth reactive current to be output, wherein the second control instruction is used for controlling the reactive compensation device, the new energy generator set and the energy storage system to provide reactive current for the power grid.

In some optional embodiments, the step S306 further includes:

and b1, when the sum of the first reactive current allowance, the second reactive current allowance and the third reactive current allowance is smaller than reactive current to be provided by the new energy power station, controlling the active power of the energy storage system to be reduced to meet a first preset condition, and obtaining a fourth reactive current allowance of the energy storage system.

For example, when I _res<|ΔI_t, the total reactive current margin of the new energy power station does not meet the dynamic reactive current requirement of the power grid, and the active power of the new energy power station needs to be reduced according to the principle of reactive priority during the power grid fault. Considering economy, the active power of the energy storage system is reduced first, and the total reactive margin of the energy storage system is increased. When the active power of the energy storage system is reduced to I _res≥|ΔI_t (the first preset condition), a fourth reactive current margin of the energy storage system is determined according to step S3064 described above. The calculation formula for reducing the active current of the stored energy is shown as the following formula (10):

Wherein I _BS,S is the rated current of the energy storage system.

And b2, when the sum of the first reactive current margin, the second reactive current margin and the fourth reactive current margin is larger than or equal to reactive current to be provided by the new energy power station, generating a third control instruction, wherein the third control instruction is used for controlling the reactive power compensation device, the new energy power generator set and the energy storage system to provide reactive current for the power grid.

And b3, when the sum of the first reactive current allowance, the second reactive current allowance and the fourth reactive current allowance is smaller than reactive current to be provided by the new energy power station, controlling the active power of the new energy power generator until the second preset condition is met, and obtaining a fifth reactive current allowance of the new energy power generator set.

And b4, generating a fourth control instruction when the sum of the first reactive current margin, the fourth reactive current margin and the fifth reactive current margin is larger than or equal to reactive current to be provided by the new energy power station, wherein the fourth control instruction is used for controlling the reactive compensation device, the new energy power generator set and the energy storage system to provide reactive current for the power grid.

In the embodiment of the present application, after the active power of the energy storage system is reduced to 0, I _res≥|ΔI_t | (the second preset condition) still cannot be satisfied, and at this time, the active power of the wind farm needs to be reduced, and the total reactive margin of the wind farm is increased. When the wind farm active power is reduced to I _res≥|ΔI_t, a dynamic reactive current is provided to meet grid demand, per step S3064. The calculation formula for reducing the active current of the wind power plant is shown as the following formula (11):

Wherein I _w,S is rated current of the wind power plant.

The embodiment also provides a voltage support control device for power grid fault, which is used for realizing the above embodiment and the preferred implementation manner, and the description is omitted. As used below, the term "module" may be a combination of software and/or hardware that implements a predetermined function. While the means described in the following embodiments are preferably implemented in software, implementation in hardware, or a combination of software and hardware, is also possible and contemplated.

The present embodiment provides a voltage support control device for power grid fault, as shown in fig. 4, including:

The acquiring module 401 is configured to acquire, when a grid fault is detected, a grid-connected point voltage of the new energy power station, reactive power of the reactive compensation device, active power of the new energy generator set, and active power of the energy storage system;

a first determining module 402, configured to determine reactive current to be provided by the new energy power station according to voltage of a grid-connected point of the new energy power station;

A second determining module 403, configured to determine a first reactive current margin of the reactive compensation device according to the reactive power of the reactive compensation device;

A third determining module 404, configured to determine a second reactive current margin of the new energy generator set according to the active power of the new energy generator set;

A fourth determining module 405, configured to determine a third reactive current margin of the energy storage system according to the active power of the energy storage system;

The instruction generating module 406 is configured to generate a voltage control instruction according to the first reactive current margin, the second reactive current margin, the third reactive current margin, and reactive current to be provided by the new energy power station, where the voltage control instruction is used to control the reactive compensation device, the new energy power generator set, and the energy storage system to provide reactive current to the power grid.

In some alternative embodiments, the acquisition module 401 includes:

The first acquisition submodule is used for acquiring actual measurement voltage of a grid connection point and rated voltage of the grid connection point of the new energy power station;

the judging sub-module is used for judging whether the power grid fails or not based on the actual measurement voltage of the grid connection point of the new energy power station, the rated voltage of the grid connection point and the preset voltage fluctuation range, and obtaining a judging result.

In some alternative embodiments, the first determining module 402 includes:

The second acquisition submodule is used for acquiring the rated current value of the grid-connected point of the new energy power station;

the first determining sub-module is used for determining the voltage per unit value of the grid-connected point of the new energy power station based on the actual measured voltage of the grid-connected point of the new energy power station and the rated voltage of the grid-connected point;

And the second determining submodule is used for determining reactive current to be provided by the new energy power station based on the per unit value of the voltage of the grid-connected point of the energy power station and the rated current value of the grid-connected point of the new energy power station.

In some alternative embodiments, the second determining module includes:

the third acquisition submodule is used for acquiring rated capacity of the reactive power compensation device;

The third determining submodule is used for determining the reactive power margin of the reactive power compensation device based on the rated capacity of the reactive power compensation device, the reactive power of the reactive power compensation device and the reactive current to be provided by the new energy power station;

And the fourth determining submodule is used for determining the first passive current margin based on the reactive power margin of the reactive compensation device and the grid-connected point voltage of the new energy power station.

In some alternative embodiments, the third determining module includes:

The fourth acquisition submodule is used for acquiring the maximum apparent power respectively corresponding to different generator sets;

a fifth determining submodule, configured to determine a reactive power margin of each new energy generator set based on the active power and the maximum apparent power of the corresponding new energy generator set;

a sixth determining submodule for determining the total reactive power margin of different new energy generator sets;

And the seventh determining submodule is used for determining a second reactive current margin based on the total reactive power margin of different new energy generator sets and the grid-connected point voltage of the new energy power station.

In some alternative embodiments, the energy storage system includes a plurality of energy storage inverters, and the fourth determination module includes:

A fifth acquisition sub-module, configured to acquire active power and maximum apparent power output by each energy storage inverter in the energy storage system;

An eighth determining submodule, configured to determine a reactive power margin of the corresponding energy storage inverter based on the active power and the maximum apparent power output by each energy storage inverter;

a ninth determination submodule for determining a total reactive power margin of the different energy-storing inverters;

And a tenth determination submodule, configured to determine a third reactive current margin based on the total reactive power margin of the different energy storage inverters and the grid-tie point voltage of the new energy power station.

In some alternative embodiments, the instruction generation module includes:

The comparison sub-module is used for comparing the reactive current to be provided by the new energy power station with the sum of the first reactive current allowance and the third reactive current allowance to obtain a comparison result;

An eleventh determining submodule, configured to determine a first reactive current to be output of the reactive compensation device and a second reactive current to be output of the energy storage system when the reactive current to be provided by the new energy power station is less than or equal to a sum of the first reactive current margin and the third reactive current margin;

the first instruction generation submodule is used for generating a first control instruction according to the first reactive current to be output and the second reactive current to be output, and the first control instruction is used for controlling the reactive compensation device and the energy storage system to provide reactive current for the power grid;

A twelfth determining submodule, configured to determine a third reactive current to be output of the reactive compensation device, a fourth reactive current to be output of the energy storage system, and a fifth reactive current to be output of the new energy generator set when the reactive current to be provided by the new energy power station is greater than the sum of the first reactive current margin and the third reactive current margin;

The second instruction generation submodule is used for generating a second control instruction based on the third reactive current to be output, the fourth reactive current to be output and the fifth reactive current to be output, and the second control instruction is used for controlling the reactive compensation device, the new energy generator set and the energy storage system to provide reactive current for the power grid.

In some alternative embodiments, the instruction generation module further comprises:

The first control submodule is used for controlling the active power of the energy storage system to be reduced to meet a first preset condition when the sum of the first reactive current allowance, the second reactive current allowance and the third reactive current allowance is smaller than reactive current to be provided by the new energy power station, so as to obtain a fourth reactive current allowance of the energy storage system;

The third instruction generation submodule is used for generating a third control instruction when the sum of the first reactive current allowance, the second reactive current allowance and the fourth reactive current allowance is larger than or equal to reactive current to be provided by the new energy power station, and the third control instruction is used for controlling the reactive compensation device, the new energy power generator set and the energy storage system to provide reactive current for the power grid;

The second control submodule is used for controlling the active power of the new energy power generator to meet a second preset condition when the sum of the first reactive current allowance, the second reactive current allowance and the fourth reactive current allowance is smaller than the reactive current to be provided by the new energy power station, so as to obtain a fifth reactive current allowance of the new energy power generator set;

And the fourth instruction generation submodule is used for generating a fourth control instruction when the sum of the first reactive current allowance, the fourth reactive current allowance and the fifth reactive current allowance is larger than or equal to reactive current to be provided by the new energy power station, and the fourth control instruction is used for controlling the reactive compensation device, the new energy power generator set and the energy storage system to provide reactive current for the power grid.

Further functional descriptions of the above respective modules and units are the same as those of the above corresponding embodiments, and are not repeated here.

The voltage support control device in this embodiment is in the form of a functional unit, where the unit refers to an ASIC (Application SPECIFIC INTEGRATED Circuit) Circuit, a processor and a memory that execute one or more software or firmware programs, and/or other devices that can provide the above functions.

The embodiment of the invention also provides computer equipment, which is provided with the voltage support control device for the power grid fault shown in the figure 4.

Referring to fig. 5, fig. 5 is a schematic structural diagram of a computer device according to an alternative embodiment of the present invention, and as shown in fig. 5, the computer device includes one or more processors 10, a memory 20, and interfaces for connecting components, including a high-speed interface and a low-speed interface. The various components are communicatively coupled to each other using different buses and may be mounted on a common motherboard or in other manners as desired. The processor may process instructions executing within the computer device, including instructions stored in or on memory to display graphical information of the GUI on an external input/output device, such as a display device coupled to the interface. In some alternative embodiments, multiple processors and/or multiple buses may be used, if desired, along with multiple memories and multiple memories. Also, multiple computer devices may be connected, each providing a portion of the necessary operations (e.g., as a server array, a set of blade servers, or a multiprocessor system). One processor 10 is illustrated in fig. 5.

The processor 10 may be a central processor, a network processor, or a combination thereof. The processor 10 may further include a hardware chip, among others. The hardware chip may be an application specific integrated circuit, a programmable logic device, or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general-purpose array logic, or any combination thereof.

Wherein the memory 20 stores instructions executable by the at least one processor 10 to cause the at least one processor 10 to perform the methods shown in implementing the above embodiments.

The memory 20 may include a storage program area that may store an operating system, application programs required for at least one function, and a storage data area that may store data created according to the use of the computer device, etc. In addition, the memory 20 may include high-speed random access memory, and may also include non-transitory memory, such as at least one magnetic disk storage device, flash memory device, or other non-transitory solid-state storage device. In some alternative embodiments, memory 20 may optionally include memory located remotely from processor 10, which may be connected to the computer device via a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.

The memory 20 may comprise volatile memory, such as random access memory, or nonvolatile memory, such as flash memory, hard disk or solid state disk, or the memory 20 may comprise a combination of the above types of memory.

The computer device also includes a communication interface 30 for the computer device to communicate with other devices or communication networks.

The embodiments of the present invention also provide a computer readable storage medium, and the method according to the embodiments of the present invention described above may be implemented in hardware, firmware, or as a computer code which may be recorded on a storage medium, or as original stored in a remote storage medium or a non-transitory machine readable storage medium downloaded through a network and to be stored in a local storage medium, so that the method described herein may be stored on such software process on a storage medium using a general purpose computer, a special purpose processor, or programmable or special purpose hardware. The storage medium may be a magnetic disk, an optical disk, a read-only memory, a random-access memory, a flash memory, a hard disk, a solid state disk, or the like, and further, the storage medium may further include a combination of the above types of memories. It will be appreciated that a computer, processor, microprocessor controller or programmable hardware includes a storage element that can store or receive software or computer code that, when accessed and executed by the computer, processor or hardware, implements the methods illustrated by the above embodiments.

Although embodiments of the present invention have been described in connection with the accompanying drawings, various modifications and variations may be made by those skilled in the art without departing from the spirit and scope of the invention, and such modifications and variations fall within the scope of the invention as defined by the appended claims.

Claims (8)

1. A method for voltage support control in the event of a grid fault, the method comprising:

When the power grid fault is monitored, acquiring grid-connected point voltage of a new energy power station, reactive power of a reactive compensation device, active power of a new energy generator set and active power of an energy storage system;

Determining reactive current to be provided by the new energy power station according to the voltage of the grid connection point of the new energy power station;

determining a first active current margin of the reactive power compensation device according to the reactive power of the reactive power compensation device;

Determining a second reactive current margin of the new energy generator set according to the active power of the new energy generator set;

determining a third reactive current margin of the energy storage system according to the active power of the energy storage system;

Generating a voltage control instruction according to the first reactive current margin, the second reactive current margin, the third reactive current margin and reactive current to be provided by the new energy power station, wherein the voltage control instruction is used for controlling a reactive power compensation device, a new energy power generator set and the energy storage system to provide reactive current for a power grid;

When the grid fault is monitored, before the step of obtaining the grid-connected point voltage of the new energy power station, the reactive power of the reactive compensation device, the active power of the new energy generator set and the active power of the energy storage system, the method further comprises:

Obtaining actual measurement voltage of a grid connection point of a new energy power station and rated voltage of the grid connection point;

Judging whether the power grid fails or not based on the actual measured voltage of the grid connection point of the new energy power station, the rated voltage of the grid connection point and the preset voltage fluctuation range, and obtaining a judging result;

Determining reactive current to be provided by the new energy power station according to the voltage of the grid connection point of the new energy power station, wherein the method comprises the following steps:

acquiring a rated current value of a new energy power station grid-connected point;

Determining the per unit value of the voltage of the grid-connected point of the new energy power station based on the actual measured voltage of the grid-connected point of the new energy power station and the rated voltage of the grid-connected point, wherein the per unit value of the voltage of the grid-connected point of the new energy power station is represented by U _t, U _g represents the voltage of the grid-connected point of the new energy power station, and U _N represents the rated voltage of the grid-connected point;

Determining reactive current to be provided by the new energy power station based on the per unit value of the voltage of the grid-connected point of the energy power station and the rated current value of the grid-connected point of the new energy power station;

the reactive current to be provided by the new energy power station is determined by the following formula:

Wherein delta I _t is reactive current to be provided by the new energy power station, K ₁、K₂ is a dynamic reactive current proportionality coefficient, and I _N represents a rated current value of the new energy power station grid-connected point;

the method for determining the first active current margin of the reactive power compensation device according to the reactive power of the reactive power compensation device comprises the following steps:

acquiring rated capacity of the reactive power compensation device;

Determining a reactive power margin of the reactive compensation device based on rated capacity of the reactive compensation device, reactive power of the reactive compensation device and reactive current to be provided by a new energy power station;

the reactive power margin of the reactive compensation device is determined by the following formula:

wherein S _svg is the rated capacity of the SVG, Q _svg,r is the reactive power of the SVG, and Q _svg,res is the reactive power margin of the SVG;

determining the first passive current margin based on the reactive power margin of the reactive power compensation device and the grid-connected point voltage of the new energy power station;

the first passive current margin is calculated by the following formula:

Wherein I _svg,res is a first active current margin;

The new energy power station comprises a plurality of new energy power generating sets, and the step of determining a second reactive current margin of the new energy power generating sets according to the active power of the new energy power generating sets comprises the following steps:

obtaining the maximum apparent power respectively corresponding to different generator sets;

determining a reactive power margin of each new energy generator set based on the active power and the maximum apparent power of the new energy generator set;

the reactive power margin of the new energy generator set is calculated by the following formula:

Wherein Q _w,res,g represents the reactive power margin of the g-th generator set, P _w,g represents the active power of the g-th generator set, and S _w,g represents the maximum apparent power of the g-th generator set;

determining the total reactive power margin of different new energy generator sets;

The total reactive power margin of the different new energy generator sets is determined by the following formula:

Wherein, Q _w,res is the total reactive power allowance of different new energy generator sets, g is the identification of the new energy generator sets, and n is the number of the new energy generator sets;

Determining the second reactive current margin based on the total reactive power margin of the different new energy generator sets and the grid-connected point voltage of the new energy power station;

the second reactive current margin is determined by:

Wherein I _w,res is a second reactive current margin;

the energy storage system comprises a plurality of energy storage inverters, and the step of determining a third reactive current margin of the energy storage system according to the active power of the energy storage system comprises the following steps:

active power and maximum apparent power output by each energy storage inverter in the energy storage system are obtained;

Determining a reactive power margin of the corresponding energy storage inverter based on the active power and the maximum apparent power output by each energy storage inverter;

The reactive power margin of the energy storage inverter is determined by:

wherein, Q _BS,res,j is the reactive power margin of the jth energy storage inverter, the maximum apparent power of the jth energy storage inverter of S _BS,j, and P _BS,j represents the active power output by the jth energy storage inverter;

determining the total reactive power margin of different energy storage inverters;

The total reactive power margin of the different energy storage inverters is determined by the love:

Wherein Q _BS,res is the total reactive power margin, and m is the number of inverters of the energy storage system;

Determining the third reactive current margin based on the total reactive power margin of the different energy storage inverters and the grid-connected point voltage of the new energy power station;

the third reactive current margin is determined by:

wherein I _BS,res is a third reactive current margin;

generating a voltage control instruction according to the first reactive current margin, the second reactive current margin, the third reactive current margin and reactive current to be provided by the new energy power station, wherein the voltage control instruction comprises the following steps:

comparing the reactive current to be provided by the new energy power station with the sum of the first reactive current allowance and the third reactive current allowance to obtain a comparison result;

when the reactive current to be provided by the new energy power station is smaller than or equal to the sum of the first reactive current margin and the third reactive current margin, determining a first reactive current to be output of the reactive compensation device and a second reactive current to be output of the energy storage system;

the first reactive current to be output of the reactive compensation device is determined by the following formula:

Wherein I _svg represents the reactive current to be output of the reactive compensation device;

The second reactive current to be output of the energy storage system is determined by the following formula:

I_BS＝ΔI_t-I_svg

Wherein I _BS represents reactive current to be output of the energy storage system;

generating a first control instruction according to the first reactive current to be output and the second reactive current to be output, wherein the first control instruction is used for controlling a reactive compensation device and the energy storage system to provide reactive current for a power grid;

When the reactive current to be provided by the new energy power station is larger than the sum of the first reactive current margin and the third reactive current margin, determining a third reactive current to be output of the reactive compensation device, a fourth reactive current to be output of the energy storage system and a fifth reactive current to be output of the new energy power generator set;

The third reactive current to be output of the reactive compensation device is determined by the following formula:

the fourth reactive current to be output of the energy storage system is determined by the following formula:

The fifth reactive current to be output of the new energy generator set is determined by the following formula:

I_w＝ΔI_t-I_svg-I_BS

Wherein I _w represents a fifth reactive current to be output of the new energy generator set;

Generating a second control instruction based on the third reactive current to be output, the fourth reactive current to be output and the fifth reactive current to be output, wherein the second control instruction is used for controlling a reactive power compensation device, a new energy generator set and the energy storage system to provide reactive current for a power grid;

Generating a voltage control instruction according to the first reactive current margin, the second reactive current margin, the third reactive current margin and reactive current to be provided by the new energy power station, and further comprising:

When the sum of the first reactive current margin, the second reactive current margin and the third reactive current margin is smaller than reactive current to be provided by the new energy power station, controlling the active power of the energy storage system to be reduced to meet a first preset condition, and obtaining a fourth reactive current margin of the energy storage system;

The first preset condition is that the active power of the energy storage system is reduced to I _res≥|ΔI_t I, and the active current for reducing the energy storage is obtained through the following formula:

Wherein I _BS,S is the rated current of the energy storage system;

When the active power of the energy storage system is reduced to 0, the second preset condition I _res≥|ΔI_t I still cannot be met, the active power of the wind power plant is reduced, the total reactive margin of the wind power plant is increased, and when the active power of the wind power plant is reduced to I _res≥|ΔI_t I, the active current of the wind power plant is reduced by the following formula:

Wherein I _w,S is rated current of the wind power plant;

When the sum of the first reactive current margin, the second reactive current margin and the fourth reactive current margin is larger than or equal to reactive current to be provided by the new energy power station, generating a third control instruction, wherein the third control instruction is used for controlling a reactive power compensation device, a new energy power generator set and the energy storage system to provide reactive current for a power grid;

When the sum of the first reactive current margin, the second reactive current margin and the fourth reactive current margin is smaller than reactive current to be provided by the new energy power station, controlling the active power of the new energy power generator until a second preset condition is met, and obtaining a fifth reactive current margin of the new energy power generator set;

and when the sum of the first reactive current margin, the fourth reactive current margin and the fifth reactive current margin is larger than or equal to reactive current to be provided by the new energy power station, generating a fourth control instruction, wherein the fourth control instruction is used for controlling a reactive compensation device, a new energy power generator set and the energy storage system to provide reactive current for a power grid.

2. A voltage support control device for use in a power grid fault, for performing the method of claim 1, the device comprising:

The acquisition module is used for acquiring grid-connected point voltage of the new energy power station, reactive power of the reactive compensation device, active power of the new energy generator set and active power of the energy storage system when the power grid fault is monitored;

The first determining module is used for determining reactive current to be provided by the new energy power station according to the voltage of the grid-connected point of the new energy power station;

The second determining module is used for determining a first passive current allowance of the reactive power compensation device according to the reactive power of the reactive power compensation device;

The third determining module is used for determining a second reactive current margin of the new energy generator set according to the active power of the new energy generator set;

A fourth determining module, configured to determine a third reactive current margin of the energy storage system according to an active power of the energy storage system;

The instruction generation module is used for generating a voltage control instruction according to the first reactive current allowance, the second reactive current allowance, the third reactive current allowance and reactive current to be provided by the new energy power station, and the voltage control instruction is used for controlling a reactive power compensation device, a new energy power generator set and the energy storage system to provide reactive current for a power grid.

3. The apparatus of claim 2, wherein the acquisition module comprises:

The first acquisition submodule is used for acquiring actual measurement voltage of a grid connection point and rated voltage of the grid connection point of the new energy power station;

And the judging sub-module is used for judging whether the power grid fails or not based on the actual measured voltage of the grid connection point, the rated voltage of the grid connection point and the preset voltage fluctuation range of the new energy power station, and obtaining a judging result.

4. The apparatus of claim 3, wherein the first determining module comprises:

The second acquisition submodule is used for acquiring the rated current value of the grid-connected point of the new energy power station;

the first determining sub-module is used for determining the voltage per unit value of the grid-connected point of the new energy power station based on the actual measured voltage of the grid-connected point of the new energy power station and the rated voltage of the grid-connected point;

And the second determining submodule is used for determining reactive current to be provided by the new energy power station based on the per unit value of the voltage of the grid-connected point of the energy power station and the rated current value of the grid-connected point of the new energy power station.

5. The apparatus of claim 2, wherein the second determining module comprises:

The third acquisition submodule is used for acquiring rated capacity of the reactive power compensation device;

A third determining submodule, configured to determine a reactive power margin of the reactive power compensation device based on a rated capacity of the reactive power compensation device, a reactive power of the reactive power compensation device, and a reactive current to be provided by the new energy power station;

and the fourth determining submodule is used for determining the first active current margin based on the reactive power margin of the reactive compensation device and the grid-connected point voltage of the new energy power station.

6. The apparatus of claim 2, wherein the third determination module comprises:

The fourth acquisition submodule is used for acquiring the maximum apparent power respectively corresponding to different generator sets;

a fifth determining submodule, configured to determine a reactive power margin of each new energy generator set based on the active power and the maximum apparent power of the corresponding new energy generator set;

a sixth determining submodule for determining the total reactive power margin of different new energy generator sets;

And a seventh determining submodule, configured to determine the second reactive current margin based on the total reactive power margin of the different new energy generator sets and the grid-connected point voltage of the new energy power station.

7. A computer device, comprising:

the system comprises a memory and a processor, wherein the memory and the processor are in communication connection, the memory stores computer instructions, and the processor executes the computer instructions, so that the voltage support control method in the power grid fault condition of claim 1 is executed.

8. A computer-readable storage medium having stored thereon computer instructions for causing a computer to execute the grid fault-time voltage support control method of claim 1.