A fault matching control method and system suitable for a grid-forming energy storage under an isolated grid

Abstract

A kind of new energy matching control method and system suitable for grid type energy storage fault under isolated network, real-time detection of grid type energy storage operating state in microgrid under isolated network mode, when grid type energy storage partial fault exits operation or limit power operation, input grid type energy storage coordination control start matching new energy control strategy, according to the size of new energy capacity and the capacity that grid type energy storage can support, realize the coordinated control of new energy power generation equipment;After completing the coordinated control of new energy power generation equipment, input grid type energy storage coordination control start matching load control strategy, according to the size of the capacity that grid type energy storage and new energy can support, realize the optimization control to the load connected in isolated network.A kind of new energy matching control method suitable for grid type energy storage fault under isolated network is used, the collaborative control of grid type energy storage in microgrid under isolated network mode is realized, human intervention operation is reduced, and the safe and stable operation of power grid is ensured.

Description

TECHNICAL FIELD

[0001] The application relates to a grid-forming energy storage fault matching control method and system suitable for a stand-alone grid, and belongs to the technical field of new energy power transmission. BACKGROUND

[0002] In the current power system, the grid-side converters of a large number of existing wind power, photovoltaic and other new energy generators and energy storage devices almost all adopt grid-following control, and rarely have active support function, and cannot provide inertia response and frequency / voltage control capability similar to traditional synchronous generators. With the increase of the proportion of new energy in the system, the above problems make the transient disturbance resistance and small signal disturbance resistance of the power grid decrease, especially in a weak power grid with low short-circuit ratio, which increases the risk of system instability, and therefore the demand for grid-forming technology is increasing. Under the existing technical background, energy storage is one of the effective means to solve the operation of the power grid, but the capacity of a single energy storage is limited, and multiple energy storage systems need to be connected in parallel to form a parallel energy storage system to solve the transient stability problem in the operation of the power grid. However, since the energy storage system contains grid-forming control and grid-following control at this time, the control stability after parallel connection becomes a key problem.

[0003] Chinese Patent Application CN202410452863.6 discloses a coordinated control method of energy storage converters in off-grid operation mode, which builds a photovoltaic power generation grid-connected unit, an energy storage converter, a 10kV AC bus and an electrolytic hydrogen production load unit to form a photovoltaic storage hydrogen isolated grid DC microgrid, wherein the energy storage converter adopts a droop control strategy. Based on the power balance characteristics of the photovoltaic storage hydrogen isolated grid DC microgrid, the mapping of bus voltage frequency to energy storage power is used to coordinate the switching of the electrolytic hydrogen production load unit and the load increase / decrease, so as to realize the system power balance of the photovoltaic storage hydrogen isolated grid DC microgrid. However, this technical solution does not consider the coordinated matching between energy storage, load and new energy, and cannot quickly solve the stability problem of isolated grid operation. SUMMARY

[0004] The purpose of the present application is to provide a grid-forming energy storage fault matching control method and system suitable for an isolated grid.

[0005] The purpose of the present application can be achieved by adopting the following technical solutions:

[0006] A grid-forming energy storage fault new energy matching control method suitable for an isolated grid, wherein the microgrid includes grid-forming energy storage, grid-following energy storage, new energy power generation equipment and load; the method comprises the following steps:

[0007] Step 1: Real-time detection of the operation state of the grid-forming energy storage in the isolated grid mode microgrid;

[0008] Step 2: When the grid-forming energy storage part is out of operation or in limited power operation, the grid-following energy storage device is put into slope control auxiliary voltage and frequency stability maintenance, and it is judged whether the capacity of the new energy power generation device is greater than the current running grid-forming energy storage supportable capacity. If it is less than, the new energy power generation device that can be newly added is calculated and limited; if it is equal to, the newly added new energy power generation device is prohibited to be put into operation; if it is greater than, step 3 is entered, and the grid-forming energy storage starts the matching control strategy;

[0009] Step 3: It is judged whether the current new energy real-time power generation power is greater than the current running grid-forming energy storage supportable capacity. If it is greater than, step 4 is entered, and if it is not greater than, step 5 is entered;

[0010] Step 4: The new energy power generation power is calculated and sorted, and the part of the new energy power generation device that needs to be shut down is calculated to put as many new energy power generation devices as possible into operation under the condition that the new energy power generation limit value is lower than the preset value. When the new energy power generation device shut-down capacity is less than the set value, the circuit breaker of the part of the new energy power generation device that needs to be shut down is tripped to access the isolated network. Then step 6 is entered;

[0011] Step 5: The new energy power generation power is calculated and sorted, and the new energy power generation device that can be newly added is calculated to put as many new energy power generation devices as possible into operation under the condition that the new energy power generation limit value is lower than the preset value. It is further judged whether the new energy power generation limit value after being newly added is less than the limit preset value. If it is less than, the grid-forming energy storage device is switched to constant voltage control, and if it is not less than, the circuit breaker of the part of the new energy power generation device that needs to be shut down is tripped to access the isolated network. Then step 6 is entered;

[0012] Step 6: It is judged whether the total load of the load accessing the isolated network and the new energy and the grid-forming energy storage supportable capacity after matching control is greater than or not. When the power load is not greater than the new energy and the grid-forming energy storage supportable capacity after matching control, the newly added load is calculated and limited; otherwise, step 7 is entered;

[0013] Step 7: It is judged whether the adjustable load accessing the isolated network satisfies the capacity matching. If it satisfies, the corresponding adjustable load that needs to be cut off is calculated. When the adjustable load that needs to be cut off is greater than the load set value, the non-adjustable load is cut off in order from low to high according to the load importance. When the adjustable load that needs to be cut off is not greater than the load set value, the adjustable load circuit breaker is tripped. If the adjustable load does not satisfy the matching capacity, the adjustable load and the non-adjustable load are cut off in order from low to high according to the load importance.

[0014] Further preferably,

[0015] In step 2, when the network-constructing energy storage part is in partial failure, the follow-network energy storage device is put into slope control, the slope active and reactive power instructions are generated according to the predetermined slope and based on the voltage amplitude deviation and frequency deviation, and the slope active and reactive power instructions are superimposed on the active and reactive power output instructions after limiting to adjust the active and reactive power of the follow-network energy storage.

[0016] Further preferably,

[0017] In step 2, when it is judged that the new energy power generation device capacity is less than the current running network-constructing energy storage supportable capacity, the new energy power generation device can be added capacity is calculated under the following conditions:

[0018] When the microgrid is in grid-connected operation, the network-constructing energy storage capacity needs to be ensured to be not less than 20% of the new energy power generation device capacity;

[0019] When the microgrid is in island operation, the network-constructing energy storage capacity needs to be ensured to be not less than 25% of the new energy power generation device capacity.

[0020] Further preferably,

[0021] In step 4, the running new energy power generation devices are sorted according to the power size, and the new energy power generation device capacity that needs to be shut down when the new energy power generation limit value is lower than the preset value is calculated in the following manner:

[0022] The new energy power generation capacity and all new energy power generation device combinations in the range of [η, 1.075η] are obtained, and the capacity and q of each combination are calculated K ;

[0023] The comparison parameter λ of each combination is calculated K , and the new energy power generation device combination with the smallest comparison parameter is selected as the new energy power generation device that needs to be shut down;

[0024]

[0025] wherein q K is the capacity of the Kth group, n k is the number of new energy power generation devices in the Kth group, n represents the average number of new energy power generation devices in all combinations, and η is the difference between the preset value and the new energy power generation limit value.

[0026] Further preferably,

[0027] The preset value = k*(current running network-constructing energy storage supportable capacity-new energy power generation power);

[0028] wherein k is a margin coefficient greater than or equal to 1.

[0029] Further preferably,

[0030] Step 4 further includes, when the outage capacity of the new energy power generation equipment is not less than the set value, starting the new energy power generation equipment with smaller capacity based on the sorting, and ensuring that the real-time power at startup does not exceed the supportable capacity of the grid-type energy storage, until the outage capacity of the new energy power generation equipment is less than the set value.

[0031] More preferably,

[0032] In step 5, the operating new energy power generation equipment is sorted according to the power size, and the new energy power generation equipment is put into use as much as possible when the new energy power generation limit value is lower than the preset value according to the following method;

[0033] Obtain the newly added new energy power generation capacity and all new energy power generation equipment combinations within the range of [0.95η,η], and calculate the capacity and q of each combination kz , and then introduce capacity for correction;

[0034] Calculate the comparison parameter λ for each combination kz ,Select a group of new energy power generation equipment with the largest comparison parameters as the new energy power generation equipment that needs to be shut down;

[0035]

[0036] Among them, q kz refers to the capacity and n of group k z It refers to the number of new energy power generation equipment combinations that can be newly invested, and η is the difference between the limit preset value and the new energy power generation limit value.

[0037] More preferably,

[0038] In step 6, when the power load is no greater than the supported capacity of the new energy and grid-connected energy storage after matching control, the newly added load is calculated and limited to meet the newly added load, and the AC frequency of the isolated grid is stabilized in the range of [0.95f, f], where f is the rated value of the AC frequency.

[0039] More preferably,

[0040] In step 7, it is judged whether the adjustable load in the access isolated network load meets the capacity matching, when the AC power grid voltage and frequency are stabilized in the range of [0.95, 1.05] times of the rated value after the adjustable load is cut off, the adjustable load is considered to meet the capacity matching. On the other hand, the application also discloses a matching control system for grid-forming energy storage under the condition of new energy fault based on the matching control method, which comprises a grid-forming energy storage operating state detection module, a new energy generation and grid-forming energy storage matching support judgment module, a new energy outage calculation module, a new energy addition calculation module, a power load matching judgment module and a load cutting module; characterized in that: the grid-forming energy storage operating state detection module detects the operating state of the grid-forming energy storage in the micro-grid under the isolated network mode in real time, and controls the grid-connected energy storage device to be put into the slope control when the grid-forming energy storage partially fails to operate or operates in the limited power mode;

[0041] The new energy generation and grid-forming energy storage matching support judgment module judges whether the capacity of the new energy generation device is greater than the current running capacity of the grid-forming energy storage that can be supported, if less, the allowable capacity of the new energy generation device that can be increased is calculated through the new energy addition calculation module, and if greater, it is judged whether the current real-time power generation of the new energy is greater than the current running capacity of the grid-forming energy storage that can be supported;

[0042] When the current real-time power generation of the new energy is greater than the current running capacity of the grid-forming energy storage that can be supported, the new energy outage capacity that needs to be shut down is calculated through the new energy outage calculation module, and the corresponding new energy access isolated network circuit breaker is tripped and disconnected; when the current real-time power generation of the new energy is not greater than the current running capacity of the grid-forming energy storage that can be supported, the new energy power generation that can be added is calculated by the new energy addition calculation module;

[0043] The power load matching judgment module judges the size of the total load of the access isolated network load and the new energy and the grid-forming energy storage that can be supported after matching control, when the power load is not greater than the new energy and the grid-forming energy storage that can be supported after matching control, the newly added load is calculated and limited; when the power load is greater than the new energy and the grid-forming energy storage that can be supported after matching control, the adjustable load or the non-adjustable load is cut off by the load cutting module.

[0044] The application realizes the collaborative control of the grid-forming energy storage, the new energy and the load under the isolated network mode by the matching control method for the grid-forming energy storage under the condition of new energy fault, and realizes the stable control of the power grid in the transient state. BRIEF DESCRIPTION OF DRAWINGS

[0045] Figure 1 It is a micro-grid system structure diagram;

[0046] Figure 2 It is a new energy control process schematic diagram in the matching control method for the grid-forming energy storage under the condition of new energy fault;

[0047] Figure 3 The application is suitable for a load control flow diagram of a grid-formation type energy storage fault matching control method under an isolated network. DETAILED DESCRIPTION

[0048] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions will be described clearly and completely below with reference to the drawings in the embodiments of the present application. The described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the spirit of the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0049] As shown in the accompanying Figures 2-3 The present application discloses a grid-formation type energy storage fault new energy matching control method suitable for an isolated network. Referring to the accompanying Figure 1 , the microgrid includes a grid-formation type energy storage, a grid-following type energy storage, a new energy power generation device and a load. The grid-formation type energy storage fault new energy matching control method disclosed by the present application includes the following steps:

[0050] Step 1: Real-time detection of the running state of the grid-formation type energy storage in the microgrid under the isolated network mode; the AC voltage amplitude and frequency of the microgrid are mainly maintained by the grid-formation type energy storage, and the grid-formation type energy storage control is communicated with the grid-following type energy storage, the new energy power generation device and the adjustable load through the standard power communication protocol of GOOSE, 104, etc.

[0051] Step 2: When the grid-formation type energy storage partially fails to exit operation or runs in a limited power mode, the grid-following type energy storage device is controlled to be put into slope control, the slope active and reactive power instructions are generated according to the predetermined slope and based on the voltage amplitude deviation and the frequency deviation after pi calculation, and are superimposed to the active and reactive output instructions after amplitude limiting, so as to adjust the active and reactive power of the grid-following type energy storage;

[0052] and whether the capacity of the new energy power generation device is greater than the current running grid-formation type energy storage supportable capacity is judged, if less, the new energy power generation device is calculated and limited to be newly added capacity; when the new energy power generation device is calculated to be newly added capacity, the following conditions need to be met:

[0053] When the microgrid is in grid-connected operation, the grid-formation type energy storage capacity needs to be ensured to be not less than 20% of the new energy power generation device capacity;

[0054] When the microgrid is in isolated network operation, the grid-formation type energy storage capacity needs to be ensured to be not less than 25% of the new energy power generation device capacity.

[0055] If equal, the newly added new energy power generation device is prohibited to be put into operation; if greater, step 3 is entered, and the grid-formation type energy storage starts the matching control strategy.

[0056] Step 3: Determine whether the current real-time new energy power generation is greater than the current running network-type energy storage support capacity, if yes, go to step 4, otherwise, go to step 5;

[0057] Step 4: Calculate and sort the new energy power generation, and calculate the part of new energy power generation equipment that needs to be shut down to put as many new energy power generation equipment as possible under the condition that the new energy power generation limiting value is lower than the preset value, when the new energy power generation equipment shutdown capacity is less than the set value, trip the circuit breaker of the part of new energy power generation equipment that needs to be shut down to access the isolated network; when the new energy power generation equipment shutdown capacity is not less than the set value, start the new energy power generation equipment with smaller capacity based on the sorting, and ensure that the starting real-time power does not exceed the network-type energy storage support capacity, until the new energy power generation equipment shutdown capacity is less than the set value; then go to step 6;

[0058] The preset value = k * (current running network-type energy storage support capacity - new energy power generation);

[0059] Wherein, k is a margin coefficient greater than or equal to 1.

[0060] The running new energy power generation equipment is sorted according to the power size, and the new energy power generation equipment capacity that needs to be shut down to meet the new energy power generation limiting value lower than the preset value is calculated as follows:

[0061] Get the new energy power generation capacity and all new energy power generation equipment combinations in the range of [η, 1.075η], and calculate the capacity and q K of each combination;

[0062] Calculate the comparison parameter λ K of each combination, and select the new energy power generation equipment combination with the smallest comparison parameter as the new energy power generation equipment that needs to be shut down;

[0063]

[0064] Wherein, q K is the capacity of the Kth group, n k is the number of new energy power generation equipment in the Kth group, represents the average number of new energy power generation equipment in all combinations, and η is the difference between the preset value and the new energy power generation limiting value.

[0065] Step 5: Calculate, sort the new energy power generation, and calculate the new energy power generation equipment that can be added to make the new energy power generation limit value lower than the preset value, further judge whether the new energy power generation limit value is less than the limit preset value after adding, if less than, switch the grid-connected type energy storage device to constant voltage control, if not less than, trip the circuit breaker of the part of new energy power generation equipment that needs to be shut down and access to the isolated network; then enter step 6;

[0066] The limit preset value = k * (current running grid-connected type energy storage supportable capacity-new energy power generation), k is a margin coefficient greater than or equal to 1.

[0067] The running new energy power generation equipment is sorted according to the power size, and the new energy power generation equipment that can be added to the running new energy power generation equipment is calculated as follows:

[0068] Get the new energy power generation capacity that can be added to the running new energy power generation equipment and all new energy power generation equipment combinations in the range of [0.95η,η], and calculate the capacity and q of each combination kz , and then introduce the capacity for correction;

[0069] Calculate the comparison parameter λ of each combination kz , select the new energy power generation equipment combination with the maximum comparison parameter as the new energy power generation equipment that needs to be shut down;

[0070]

[0071] Wherein, q kz is the capacity of the kth group, n z is the number of new energy power generation equipment combinations that can be added, and η is the difference between the limit preset value and the new energy power generation limit value.

[0072] Step 6: Judge the size of the total load of the load connected to the isolated network and the new energy and grid-connected type energy storage supportable capacity after matching control, when the power load is not greater than the new energy and grid-connected type energy storage supportable capacity after matching control, calculate and limit the added load; otherwise, enter step 7;

[0073] Step 7: Judge whether the adjustable load in the load connected to the isolated network meets the capacity matching, if yes, calculate the required cut-off corresponding adjustable load, when the required cut-off adjustable load is greater than the load setting value, cut off the non-adjustable load in order from low to high according to the load importance, when the required cut-off adjustable load is not greater than the load setting value, trip the adjustable load circuit breaker; if the adjustable load does not meet the matching capacity, cut off the adjustable load and cut off the non-adjustable load in order from low to high according to the load importance.

[0074] The application also discloses a new energy matching control system based on the matching control method and suitable for grid-forming energy storage under an isolated grid, which comprises a grid-forming energy storage operating state detection module, a new energy generation and grid-forming energy storage matching support judgment module, a new energy outage calculation module, a new energy addition calculation module, a power load matching judgment module and a load removal module.

[0075] The new energy generation and grid-forming energy storage matching support judgment module judges whether the capacity of the new energy generation device is greater than the current running grid-forming energy storage supportable capacity, if less, the new energy addition calculation module is used to calculate the allowable new energy generation device capacity, and if greater, the current new energy real-time generation power is judged whether greater than the current running grid-forming energy storage supportable capacity.

[0076] When the current new energy real-time generation power is greater than the current running grid-forming energy storage supportable capacity, the new energy outage calculation module is used to calculate the new energy outage capacity, and the corresponding new energy access isolated grid circuit breaker is tripped and disconnected; when the current new energy real-time generation power is not greater than the current running grid-forming energy storage supportable capacity, the new energy addition calculation module is used to calculate the new energy generation power.

[0077] The power load matching judgment module judges the total load of the access isolated grid and the new energy and grid-forming energy storage supportable capacity after matching control, when the power load is not greater than the new energy and grid-forming energy storage supportable capacity after matching control, the added load is calculated and limited; when the power load is greater than the new energy and grid-forming energy storage supportable capacity after matching control, the load removal module is used to remove the adjustable load or non-adjustable load.

[0078] The above has described the embodiments of the present disclosure, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those skilled in the art without departing from the scope and spirit of the described embodiments. The selection of the terms used herein is intended to best explain the principles, practical application or technical improvement in the market of the embodiments, or to enable other ordinary skilled persons in the art to understand the embodiments disclosed herein.

Claims

1. A new energy matching control method for grid-forming energy storage failure in an isolated microgrid, wherein the microgrid includes grid-forming energy storage, grid-following energy storage, new energy power generation equipment and loads; characterized in that: The method comprises the following steps: Step 1: Real-time detection of the operating status of the grid-connected energy storage in the microgrid in isolated grid mode; Step 2: When the grid-connected energy storage system partially fails and exits operation or operates at limited power, the grid-connected energy storage system is controlled to operate at a slope to assist in maintaining voltage and frequency stability. The system also determines whether the capacity of the new energy generation equipment is greater than the capacity that the currently operating grid-connected energy storage system can support. If so, the system calculates and limits the capacity that can be added to the new energy generation equipment. If so, the system prohibits the addition of new energy generation equipment. If so, the system proceeds to Step 3, where the grid-connected energy storage system initiates the matching control strategy. Step 3: Determine whether the current real-time power generation of renewable energy is greater than the capacity of the currently operating grid-connected energy storage system. If so, proceed to Step 4; otherwise, proceed to Step 5. Step 4: Calculate and sort the renewable energy power generation capacity, and calculate the portion of renewable energy power generation equipment that needs to be shut down so that as many renewable energy power generation equipment as possible are put into operation while keeping the renewable energy power generation limit below the preset value. When the shutdown capacity of the renewable energy power generation equipment is less than the set value, the circuit breaker connecting the renewable energy power generation equipment that needs to be shut down to the isolated grid is tripped; then proceed to step 6; Step 5: Calculate and sort the renewable energy power generation capacity, and calculate the renewable energy power generation equipment that can be added so that as many renewable energy power generation equipment as possible can be put into use while ensuring that the renewable energy power generation limit is lower than the preset value. Further, determine whether the renewable energy power generation limit after addition is lower than the preset limit. If so, switch the grid-connected energy storage device to constant voltage control. If not, trip the circuit breaker that connects the renewable energy power generation equipment that needs to be shut down to the isolated grid. Then proceed to Step 6. Step 6: Determine the total load of the isolated grid and the capacity that can be supported by the new energy and grid-connected energy storage after matching control. If the electricity load is not greater than the capacity that can be supported by the new energy and grid-connected energy storage after matching control, calculate and limit the newly added load; otherwise, proceed to Step 7. Step 7: Determine whether the adjustable load in the isolated grid load meets the capacity matching. If so, calculate the corresponding adjustable load to be cut off. When the adjustable load to be cut off is greater than the load setting value, cut off the non-adjustable load in order from low to high according to the load importance. When the adjustable load to be cut off is not greater than the load setting value, trip the adjustable load circuit breaker. When the adjustable load does not meet the matching capacity, cut off the adjustable load and cut off the non-adjustable load in order from low to high according to the load importance.

2. The new energy matching control method for isolated grid-connected energy storage faults according to claim 1 is characterized in that: In step 2, when the grid-type energy storage device fails and exits operation or operates with limited power, the grid-following energy storage device is controlled to put into slope control. The slope active and reactive power instructions are generated after pi calculation based on the predetermined slope and the voltage amplitude deviation and frequency deviation. After being limited, they are added to the active and reactive output instructions to adjust the active and reactive power of the grid-following energy storage device.

3. The new energy matching control method for isolated grid-connected energy storage faults according to claim 2 is characterized in that: In step 2, if the capacity of the new energy power generation equipment is determined to be less than the capacity that can be supported by the currently operating grid-connected energy storage, the additional capacity of the new energy power generation equipment is calculated under the following conditions: When the microgrid is connected to the grid, the grid-connected energy storage capacity must be no less than 20% of the capacity of the new energy power generation equipment; When the microgrid operates in an isolated network, it is necessary to ensure that the grid-connected energy storage capacity is not less than 25% of the capacity of the new energy power generation equipment.

4. The new energy matching control method for isolated grid-connected energy storage faults according to claim 1 is characterized in that: In step 4, the operating new energy power generation equipment is sorted according to the power size, and the capacity of the new energy power generation equipment that needs to be shut down when the new energy power generation limit value is lower than the preset value is calculated in the following way; Get the new energy power generation capacity and all new energy power generation equipment combinations within the range of [η,1.075η], and calculate the capacity and q of each combination K ; Calculate the comparison parameter λ for each combination K ,Select a group of new energy power generation equipment with the smallest comparison parameters as the new energy power generation equipment that needs to be shut down; Among them, q K refers to the capacity and n of group K k Refers to the number of new energy power generation equipment in group K, represents the average number of renewable energy power generation equipment in all combinations, and η is the difference between the preset value and the renewable energy power generation limit value.

5. The new energy matching control method for isolated grid-connected energy storage faults according to claim 4 is characterized in that: The preset value = k*(capacity supported by the current grid-type energy storage - power generation of new energy); Wherein, k is a margin factor greater than or equal to 1.

6. The new energy matching control method for grid-connected energy storage failure in an isolated grid according to claim 4 or 5, characterized in that: Step 4 further includes, when the outage capacity of the new energy power generation equipment is not less than the set value, starting the new energy power generation equipment with smaller capacity based on the sorting, and ensuring that the real-time power at startup does not exceed the supportable capacity of the grid-type energy storage, until the outage capacity of the new energy power generation equipment is less than the set value.

7. The new energy matching control method for isolated grid-connected energy storage faults according to claim 1 is characterized in that: In step 5, the operating new energy power generation equipment is sorted according to the power size, and the new energy power generation equipment is put into use as much as possible when the new energy power generation limit value is lower than the preset value according to the following method; Obtain the newly added new energy power generation capacity and all new energy power generation equipment combinations within the range of [0.95η,η], and calculate the capacity and q of each combination kz , and then introduce capacity for correction; Calculate the comparison parameter λ for each combination kz ,Select a group of new energy power generation equipment with the largest comparison parameters as the new energy power generation equipment that needs to be shut down; Among them, q kz refers to the capacity and n of group k z It refers to the number of new energy power generation equipment combinations that can be newly invested, and η is the difference between the limit preset value and the new energy power generation limit value.

8. The new energy matching control method for isolated grid-connected energy storage faults according to claim 1 is characterized in that: In step 6, when the power load is no greater than the supported capacity of the new energy and grid-connected energy storage after matching control, the newly added load is calculated and limited to meet the newly added load, and the AC frequency of the isolated grid is stabilized in the range of [0.95f, f], where f is the rated value of the AC frequency.

9. The new energy matching control method for isolated grid-connected energy storage faults according to claim 1 is characterized in that: In step 7, it is determined whether the adjustable load connected to the isolated grid meets the capacity matching. When the AC grid voltage and frequency are both stable within the range of [0.95, 1.05] times the rated value after the adjustable load is removed, it is considered that the adjustable load meets the capacity matching.

10. A new energy matching control system for grid-type energy storage faults in isolated power grids based on the matching control method according to any one of claims 1 to 9, comprising a grid-type energy storage operating status detection module, a new energy generation and grid-type energy storage matching support judgment module, a new energy outage calculation module, a new energy addition calculation module, a power load matching judgment module, and a load shedding module; characterized in that: The grid-type energy storage operation status detection module detects the operation status of the grid-type energy storage in the microgrid in isolated mode in real time. When the grid-type energy storage fails and stops operating or operates at limited power, the grid-type energy storage equipment is controlled to start slope control. The new energy power generation and grid-type energy storage matching support judgment module determines whether the capacity of the new energy power generation equipment is greater than the support capacity of the currently operating grid-type energy storage. If so, the new energy addition calculation module calculates the allowed additional capacity of the new energy power generation equipment. If so, the module determines whether the current real-time power generation power of the new energy is greater than the support capacity of the currently operating grid-type energy storage. When the current real-time power generation of renewable energy is greater than the capacity supported by the currently operating grid-connected energy storage, the renewable energy outage calculation module calculates the required renewable energy outage capacity and trips the corresponding renewable energy access isolated grid circuit breaker; When the current real-time power generation of renewable energy is not greater than the capacity supported by the current grid-connected energy storage, the new energy calculation module will calculate the power generation of renewable energy that can be added. The electricity load matching judgment module judges the total load of the isolated grid load and the supporting capacity of the new energy and grid-forming energy storage after matching control. When the electricity load is not greater than the supporting capacity of the new energy and grid-forming energy storage after matching control, the newly added load is calculated and limited; when the electricity load is greater than the supporting capacity of the new energy and grid-forming energy storage after matching control, the load shedding module sheaths the adjustable load or non-adjustable load.

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