Method and system for configuring network-constructed energy storage and distributed phase-modulating machine under short-circuit ratio constraint

Abstract

The application discloses a method and system for configuring grid-forming energy storage and distributed phase modifier under short-circuit ratio constraint, obtains short-circuit current at a bus of a new energy station, establishes a short-circuit capacity model at the bus of the new energy station after the distributed phase modifier or the grid-forming energy storage is configured; based on the short-circuit ratio model at the bus of the new energy station, a short-circuit ratio model at the bus of the new energy station after the distributed phase modifier or the grid-forming energy storage is configured and constraint conditions thereof are established; a short-circuit ratio constraint of multiple new energy stations after the distributed phase modifier or the grid-forming energy storage is configured is established; the optimal comprehensive cost of the distributed phase modifier or the grid-forming energy storage is taken as an objective function; the objective function, the number constraint and the capacity constraint of the distributed phase modifier or the grid-forming energy storage and the dynamic constraint of the short-circuit ratio of the multiple new energy stations constitute an optimal configuration model of the distributed phase modifier or the grid-forming energy storage; and the configuration result of the grid-forming energy storage and the distributed phase modifier under the short-circuit ratio constraint is obtained through iterative solution, so that the optimal configuration is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power systems, in particular to a network-structured energy storage and distributed phase modifier optimal configuration method and system considering multi-station short-circuit ratio linearization constraints. BACKGROUND

[0002] At present, large-scale wind and photovoltaic power bases are concentrated in areas with relatively weak grid structures. The inertia and damping characteristics of local power grids are showing a downward trend, and the dynamic reactive power support capacity is insufficient. The new energy carrying capacity (multi-station short-circuit ratio of new energy) is insufficient, which may cause problems such as transient overvoltage and wideband oscillation. Therefore, active support devices such as distributed phase modifiers or network-structured energy storages need to be configured. The network-structured energy storage can improve the regulation and support capacity of the power grid, the short-circuit capacity of the power grid, and the multi-station short-circuit ratio of new energy. It has good stability in weak power grids and can help solve the problem of support capacity "hollowing out" in new energy-rich areas. Considering the mandatory configuration of energy storage in various places, network-structured energy storage is currently being popularized and applied by major energy storage manufacturers. However, the planning and operation cost of large-scale configuration of distributed phase modifiers while ignoring the role of network-structured energy storage is difficult to bear, and there is an urgent need to optimize the configuration of network-structured energy storage and distributed phase modifiers.

[0003] In the prior art, the optimal configuration model of the distributed phase modifier in the new energy cluster based on the multi-station short-circuit ratio of new energy is as follows: first, the equivalent apparent power of each current source in the new energy cluster is determined based on the self-impedance or mutual impedance between the current sources in the new energy cluster under a determined distributed phase modifier configuration scheme; then, the multi-station short-circuit ratio of each current source in the new energy cluster is determined based on the equivalent apparent power of each current source in the new energy cluster and the short-circuit capacity of the grid connection point of each current source; finally, it is determined whether the calculated multi-station short-circuit ratio meets the requirements. If it does not meet the requirements, the distributed phase modifier configuration scheme is adjusted, the multi-station short-circuit ratio after the adjustment of the distributed phase modifier configuration scheme is calculated again, and the iteration is stopped until the multi-station short-circuit ratio finally meets the requirements of a certain limit. At this time, the distributed phase modifier configuration scheme is the optimal configuration scheme of the distributed phase modifier that meets the multi-station short-circuit ratio. However, the prior art does not consider the improvement effect of network-structured energy storage on the multi-station short-circuit ratio, and the planning scheme is inconsistent with the transient reactive power support device planning scheme in actual large-scale wind and photovoltaic power bases. Therefore, it cannot achieve the optimal configuration of large-scale network-structured energy storage and distributed phase modifiers in large-scale wind and photovoltaic power bases. At the same time, when optimizing the configuration of transient reactive power support devices based on the multi-station short-circuit ratio constraint, manual optimization of the configuration scheme is often required multiple times. The multi-station short-circuit ratio must be calculated every time the scheme is adjusted, and the iteration must be continued until the multi-station short-circuit ratio constraint is met. The calculation process is relatively complicated. SUMMARY

[0004] To solve the problems in the prior art, the application provides a network-constructed energy storage and distributed phase modifier optimal configuration method and system considering linearization constraints of multi-station short-circuit ratios, which considers the improvement effect of network-constructed energy storage and distributed phase modifier on the multi-station short-circuit ratios, linearizes the multi-station short-circuit ratio constraints, and converts the network-constructed energy storage and distributed phase modifier optimal configuration model into a linear programming problem, so that the optimal configuration of the network-constructed energy storage and distributed phase modifier can be realized without iteration, thereby providing a technical basis for the selection of the optimal configuration of the network-constructed energy storage and distributed phase modifier in a large wind-solar power base.

[0005] The application adopts the technical scheme as follows.

[0006] The application provides a network-constructed energy storage and distributed phase modifier configuration method under short-circuit ratio constraints, which is suitable for a new energy station containing network-constructed energy storage or distributed phase modifier, and includes the following steps.

[0007] The short-circuit current at the bus of the new energy station is obtained, and a short-circuit capacity model at the grid-connected bus of the new energy station after the distributed phase modifier or network-constructed energy storage is configured is established;

[0008] Based on the short-circuit ratio model at the bus of the new energy station, a short-circuit ratio model at the grid-connected bus of the new energy station after the distributed phase modifier or network-constructed energy storage is configured and its constraint condition are established;

[0009] Based on the short-circuit capacity model at the grid-connected bus of the new energy station after the distributed phase modifier or network-constructed energy storage is configured and the short-circuit ratio model at the grid-connected bus of the new energy station and its constraint condition, a new energy multi-station short-circuit ratio constraint after the distributed phase modifier or network-constructed energy storage is configured is established;

[0010] The optimal comprehensive cost of the configured distributed phase modifier or network-constructed energy storage is taken as an objective function; the objective function, the number constraint and capacity constraint of the configured distributed phase modifier or network-constructed energy storage, and the dynamic constraint of the new energy multi-station short-circuit ratio after the distributed phase modifier or network-constructed energy storage is configured jointly constitute an optimal configuration model of the distributed phase modifier or network-constructed energy storage;

[0011] The optimal configuration model of the distributed phase modifier or network-constructed energy storage is solved iteratively to obtain the configuration result of the network-constructed energy storage and distributed phase modifier under the short-circuit ratio constraint.

[0012] Preferably, the short-circuit current at the bus of the new energy station is obtained, and the short-circuit capacity model at the grid-connected bus of the new energy station after the distributed phase modifier or network-constructed energy storage is configured is established, including the following steps.

[0013] The short-circuit currents provided by the network-constructed energy storage, distributed phase modifier and alternating current system to the bus are collected, and a vector of the short-circuit current at the bus of the new energy station is calculated;

[0014] Establishing the amplitude constraint and phase angle constraint of the short-circuit current provided by the network-constructed energy storage to the bus;

[0015] Based on the amplitude constraint and phase angle constraint of the short-circuit current provided by the network-constructed energy storage to the bus, the amplitude of the short-circuit current at the bus of the new energy station is calculated;

[0016] Based on the relationship between the short-circuit capacity at the new energy grid-connected bus after the distributed phase modifier or network-constructed energy storage is configured and the short-circuit current at the bus of the new energy station, a short-circuit capacity model at the new energy station grid-connected bus after the distributed phase modifier or network-constructed energy storage is configured is established.

[0017] Preferably, the short-circuit capacity model at the new energy station grid-connected bus after the distributed phase modifier or network-constructed energy storage is configured satisfies the following relationship:

[0018]

[0019] In the formula, S aci ′ is the short-circuit capacity at the grid-connected bus i of the new energy station after the distributed phase modifier or network-constructed energy storage is configured; U Ni is the amplitude of the nominal voltage at the grid-connected bus i of the new energy station; is the amplitude of the short-circuit current at the bus of the new energy station; S base is the system reference capacity.

[0020] Preferably, based on the short-circuit ratio model at the bus of the new energy station, a short-circuit ratio model at the grid-connected bus of the new energy station is established, including:

[0021] Establishing a short-circuit ratio model at the bus of the new energy station;

[0022] Collecting the short-circuit capacity at the grid-connected bus of the new energy station and the active power injected by the grid-connected bus, and based on the short-circuit ratio model at the bus of the new energy station, a short-circuit ratio model at the grid-connected bus of the new energy station is established;

[0023] Based on the constraint of the active power conversion factor between the grid-connected buses i and j after the distributed phase modifier or network-constructed energy storage is configured, a short-circuit ratio model at the grid-connected bus of the new energy station after the distributed phase modifier or network-constructed energy storage is configured is established;

[0024] The constraint condition of the short-circuit ratio model at the grid-connected bus of the new energy station after the distributed phase modifier or network-constructed energy storage is configured is that the short-circuit ratio at the grid-connected bus of the new energy station after the distributed phase modifier or network-constructed energy storage is configured is not less than the lower limit of the short-circuit ratio at the grid-connected bus of the new energy station.

[0025] Preferably, the short-circuit ratio model MRSCR S,i satisfies the following relationship:

[0026]

[0027] where S aci is the short circuit capacity at the grid-connected bus i; P REi is the active power injected by the grid-connected bus i, P RE,j is the active power injected by the grid-connected bus j; MRSCR is the active power conversion factor of the power between the grid-connected buses i and j before the distributed phase modulator or grid-forming energy storage is configured.

[0028] Preferably, the short circuit ratio model MRSCR S,i and its constraint condition at the grid-connected bus of the new energy station after the distributed phase modulator or grid-forming energy storage is configured satisfy the following relationship:

[0029]

[0030] where S aci is the short circuit capacity at the grid-connected bus i of the new energy station after the distributed phase modulator or grid-forming energy storage is configured; MRSCR S,min is the lower limit of the short circuit ratio at the grid-connected bus of the new energy station.

[0031] Preferably, the short circuit ratio constraint of the new energy multi-station after the distributed phase modulator or grid-forming energy storage is configured satisfies the following relationship:

[0032]

[0033] where U Ni is the amplitude of the nominal voltage at the grid-connected bus i of the new energy station; is the amplitude of the short circuit current at the bus i of the new energy station; S base is the system reference capacity.

[0034] Preferably, the short circuit ratio constraint of the new energy multi-station after the distributed phase modulator or grid-forming energy storage is configured satisfies the following relationship:

[0035]

[0036] where I fb,e,i , I cn,e,i are the short circuit currents provided by the grid-forming energy storage e and the distributed phase modulator e to the bus i, respectively; e∈cn, e∈fb are voltage source type units e of the type of grid-forming energy storage or distributed phase modulator, respectively; θ cn-sys,e,i is the corresponding phase angle difference of the grid-forming energy storage e or the distributed phase modulator e, which satisfies θ cn-sys,e,i = θ cn,e,i - θ sys,i ; θ cn,e,iThe phase angle of the voltage source type unit e of the grid forming type energy storage at the bus i, θ sys,i The phase angle of the short-circuit current provided for the AC system.

[0037] Preferably, the vector of the short-circuit current at the bus of the new energy station containing the grid forming type energy storage or the distributed phase machine includes: the short-circuit current provided by the grid forming type energy storage to the bus of the new energy station, the short-circuit current provided by the distributed phase machine to the bus of the new energy station, and the short-circuit current provided by the AC system to the bus of the new energy station.

[0038] The calculation of the short-circuit current provided by the grid forming type energy storage to the bus of the new energy station or the short-circuit current provided by the distributed phase machine to the bus of the new energy station includes: clearing the internal potential of all voltage source type units in the system except the distributed phase machine or the grid forming type energy storage, and calculating the internal potential of the distributed phase machine or the grid forming type energy storage and the admittance matrix, satisfying the following relationship:

[0039]

[0040] In the formula, Y n×d is an admittance matrix of n rows by d columns, n is the number of the bus of the new energy station, d is the number of the distributed phase machine or the grid forming type energy storage, I e，1 , …, I e,i , …, I e,n are the short-circuit currents provided by the distributed phase machine or the grid forming type energy storage e to the bus 1 of the new energy station, …, the bus i of the new energy station, …, and the bus n of the new energy station, respectively.

[0041] Preferably, the optimal configuration of the distributed phase machine or the grid forming type energy storage is taken as the objective function; the objective function, the number constraint of the distributed phase machine or the grid forming type energy storage, the capacity constraint, and the dynamic constraint of the short-circuit ratio of the new energy station after the configuration of the distributed phase machine or the grid forming type energy storage together constitute an optimization configuration model of the distributed phase machine or the grid forming type energy storage, including:

[0042] The number constraint and the capacity constraint of the configuration of the distributed phase machine or the grid forming type energy storage are established;

[0043] Based on the number constraint and the capacity constraint of the configuration of the distributed phase machine or the grid forming type energy storage, a comprehensive cost model of the configuration of the distributed phase machine or the grid forming type energy storage is established, and the optimal comprehensive cost of the configuration of the distributed phase machine or the grid forming type energy storage is taken as the objective function;

[0044] Based on the number constraint of the configuration of the distributed phase machine or the grid forming type energy storage, the short-circuit ratio constraint of the new energy station after the configuration of the distributed phase machine or the grid forming type energy storage is dynamically processed to obtain the dynamic constraint of the short-circuit ratio of the new energy station after the configuration of the distributed phase machine or the grid forming type energy storage.

[0045] The objective function, the quantity constraint and capacity constraint of configuring the distributed phase modifier or grid-forming energy storage, and the dynamic constraint of the short-circuit ratio of the new energy multi-station after configuring the distributed phase modifier or grid-forming energy storage jointly constitute the optimization configuration model of the distributed phase modifier or grid-forming energy storage.

[0046] Preferably, the quantity constraint and capacity constraint of configuring the distributed phase modifier or grid-forming energy storage satisfy the following relationship respectively:

[0047]

[0048] In the formula, N fd,i , N cn,i are respectively the upper limit of the number of the distributed phase modifier or grid-forming energy storage configured at the grid-connected bus i; Q fd , Q cn are respectively the capacity upper limit of the distributed phase modifier or grid-forming energy storage configured; y fd,e,i , y cn,e,i is whether the distributed phase modifier or grid-forming energy storage e is configured at the grid-connected bus i, which is a 0-1 state variable in the non-restrictive preferred embodiment; Q fd,e,i , Q cn,e,i is the capacity of the distributed phase modifier or grid-forming energy storage e configured at the grid-connected bus i.

[0049] Preferably, the dynamic constraint of the short-circuit ratio of the new energy multi-station after configuring the distributed phase modifier or grid-forming energy storage satisfies the following relationship:

[0050]

[0051] In the formula, y fd,e,i , y cn,e,i is whether the distributed phase modifier or grid-forming energy storage e is configured at the grid-connected bus i, which is a 0-1 state variable; I fb,e,i , I cn,e,i are respectively the short-circuit current provided by the grid-forming energy storage e or the distributed phase modifier e to the bus i, e∈cn, e∈fb are respectively the voltage source type unit e of the type of grid-forming energy storage or distributed phase modifier; θ cn-sys,e,i is the corresponding phase angle difference of configuring the grid-forming energy storage e or the distributed phase modifier e, which satisfies θ cn-sys,e,i = θ cn,e,i - θ sys,i ; θ cn,e,i represents the phase angle of the voltage source type unit e of the type of grid-forming energy storage at the bus i, θ sys,i is the phase angle of the short-circuit current provided by the alternating current system; MRSCR S,min is the lower limit of the short-circuit ratio at the grid-connected bus of the new energy station; S aci is the short-circuit capacity at the grid-connected bus i; MRSCR S,iis a short-circuit ratio of a new energy station; is a short-circuit current provided by an alternating current system to a new energy station bus i.

[0052] The application further provides a configuration system of grid-forming energy storage and distributed phase-modulator under short-circuit ratio constraint, which is suitable for a new energy station containing grid-forming energy storage or distributed phase-modulator, and comprises:

[0053] a short-circuit ratio constraint establishment module, an optimal configuration model module and an optimal configuration module.

[0054] The short-circuit ratio constraint establishment module is used to obtain a short-circuit current at a bus of the new energy station, establish a short-circuit capacity model at a grid-connected bus of the new energy station after the distributed phase-modulator or the grid-forming energy storage is configured, establish a short-circuit ratio model at the grid-connected bus of the new energy station after the distributed phase-modulator or the grid-forming energy storage is configured and constraint conditions thereof based on the short-circuit ratio model at the bus of the new energy station, and establish a short-circuit ratio constraint of the new energy station after the distributed phase-modulator or the grid-forming energy storage is configured based on the short-circuit capacity model at the grid-connected bus of the new energy station after the distributed phase-modulator or the grid-forming energy storage is configured and the short-circuit ratio model at the grid-connected bus of the new energy station and the constraint conditions thereof.

[0055] The optimal configuration model module is used to take optimal comprehensive cost of the distributed phase-modulator or the grid-forming energy storage as an objective function, and the objective function, a quantity constraint of the distributed phase-modulator or the grid-forming energy storage, a capacity constraint of the distributed phase-modulator or the grid-forming energy storage and a dynamic constraint of the short-circuit ratio of the new energy station after the distributed phase-modulator or the grid-forming energy storage is configured jointly constitute an optimal configuration model of the distributed phase-modulator or the grid-forming energy storage.

[0056] The optimal configuration module is used to iteratively solve the optimal configuration model of the distributed phase-modulator or the grid-forming energy storage to obtain a configuration result of the grid-forming energy storage and the distributed phase-modulator under the short-circuit ratio constraint.

[0057] The application has the advantages that, compared with the prior art, the method proposed by the application improves the traditional distributed phase-modulator optimal configuration method based on the short-circuit ratio constraint of the new energy station, considers the influence of the grid-forming energy storage and the distributed phase-modulator on the short-circuit ratio of the new energy station, linearly expresses the short-circuit ratio constraint of the new energy station, converts the optimal configuration model of the grid-forming energy storage and the distributed phase-modulator into a linear programming problem, realizes the optimal configuration of the grid-forming energy storage and the distributed phase-modulator without iteration, and the conservativeness of the optimal configuration scheme meets the needs of engineering application. BRIEF DESCRIPTION OF DRAWINGS

[0058] Figure 1 is a system side short-circuit current schematic diagram at a grid-connected point of a new energy station containing a grid-forming energy storage and a distributed phase-modulator in the application;

[0059] Figure 2 is the system side short-circuit current vector diagram at the grid connection point of the new energy station containing the grid-forming energy storage and the distributed phase modifier in the application;

[0060] Figure 3 is the specific flow chart of the distributed phase modifier and the grid-forming energy storage optimization configuration method established in the application;

[0061] Figure 4 is the actual example system network structure schematic diagram in the embodiment of the application;

[0062] Figure 5 is the actual example system network structure schematic diagram in the embodiment of the application; DETAILED DESCRIPTION

[0063] In order to make the purpose, technical scheme and advantages of the application clearer, the technical scheme of the application will be described clearly and completely below in combination with the drawings in the embodiments of the application. The embodiments described in the application are only a part of the embodiments of the application, not all the embodiments. All other embodiments obtained by those skilled in the art without creative labor on the basis of the spirit of the application belong to the protection scope of the application.

[0064] The application proposes a grid-forming energy storage and distributed phase modifier configuration method under short-circuit ratio constraint, which is suitable for a new energy station containing a grid-forming energy storage or a distributed phase modifier, and includes the following steps.

[0065] Step 1, collect the short-circuit current at the bus of the new energy station, and establish a short-circuit capacity model at the grid connection bus of the new energy station after the distributed phase modifier or the grid-forming energy storage is configured.

[0066] Specifically, step 1 includes the following steps.

[0067] Step 1.1, collect the short-circuit currents provided by the grid-forming energy storage, the distributed phase modifier and the alternating current system to bus i, and calculate the vector of the short-circuit current at the bus of the new energy station.

[0068] In a non-limiting preferred embodiment, as shown in Figure 1 the vector of the short-circuit current at the bus of the new energy station containing the grid-forming energy storage or the distributed phase modifier satisfies the following relationship:

[0069]

[0070] In the formula, is the short-circuit current at bus i of the new energy station; are respectively the short-circuit currents provided by the grid-forming energy storage, the distributed phase modifier and the alternating current system to bus i of the new energy station.

[0071] θ cn,i, θ sys,i is the phase angle of the short-circuit current provided by the grid-forming energy storage or the distributed phase modifier to bus i.

[0072] In a non-limiting preferred embodiment, if a system is configured with d distributed phase modifiers or grid-forming energy storages, the vector of the three-phase short-circuit current at bus i of the new energy station is calculated using the Thevenin theorem and the superposition theorem comprises: after calculating the short-circuit current of each voltage source type unit acting on the new energy bus i using the Thevenin theorem, the short-circuit current at the new energy station bus i is obtained using the superposition theorem, and the following relationship is satisfied:

[0073]

[0074] wherein e∈cn, e∈fb are voltage source type units of the type of grid-forming energy storage or distributed phase modifier; represents the three-phase short-circuit current provided by the voltage source type unit e of the type of grid-forming energy storage or distributed phase modifier to bus i.

[0075] Step 1.2, establishing the amplitude constraint and phase angle constraint of the short-circuit current provided by the grid-forming energy storage to the bus;

[0076] The amplitude of the short-circuit current provided by the grid-forming energy storage to bus i is constrained by the overcurrent capability I lim of the device, and the phase angle θ cn,i of the short-circuit current provided by the grid-forming energy storage to bus i is constrained by the power outer loop control, and the following relationship is satisfied:

[0077]

[0078] wherein x cn,i is the connection impedance of the grid-forming energy storage to the system plus the virtual internal impedance of the grid-forming energy storage, and E cn,i is the terminal voltage of the grid-forming energy storage.

[0079] Step 1.3, based on the amplitude constraint and phase angle constraint of the short-circuit current provided by the grid-forming energy storage to the bus, the amplitude of the short-circuit current at the bus of the new energy station containing the grid-forming energy storage or the distributed phase modifier is calculated

[0080] Specifically, as shown in the following formula, the three-phase short-circuit fault current amplitude at the bus i of the new energy station Figure 2 satisfies the following relationship:

[0081]

[0082] wherein θ cn-sys,e,i is the phase angle difference, and θ cn-sys,e,i = θ​cn,e,i -θ sys,i ; θ cn,e,i represents the phase angle of the voltage source type unit e of the grid forming type energy storage at bus i, θ sys,i is the phase angle of the short-circuit current provided by the AC system.

[0083] Referring to Figure 2 , the power angle remains unchanged during the grid forming type energy storage sub-transient process, so by transforming the reference angle of the power angle, based on the amplitude constraint and phase angle constraint of the short-circuit current provided by the grid forming type energy storage to the bus, the reference angle of the originally 0 angle is advanced to the phase angle of the short-circuit current provided by the AC system, the short-circuit current calculation method of the grid connection point is simplified, and the establishment of the short-circuit capacity model in step 1.4 is facilitated.

[0084] Step 1.4, based on the relationship between the short-circuit capacity at the new energy grid-connected bus after the distributed phase modifier or grid forming type energy storage is configured and the short-circuit current at the new energy station bus, a short-circuit capacity model at the new energy station grid-connected bus after the distributed phase modifier or grid forming type energy storage is configured is established;

[0085] The short-circuit capacity model at the new energy station grid-connected bus after the distributed phase modifier or grid forming type energy storage is configured satisfies the following relationship:

[0086]

[0087] In the formula, S aci ′ is the short-circuit capacity at the grid-connected bus i of the new energy station after the distributed phase modifier or grid forming type energy storage is configured; U Ni is the amplitude of the nominal voltage at the grid-connected bus i of the new energy station; is the amplitude of the short-circuit current at the bus of the new energy station; S base is the system reference capacity.

[0088] Step 2, based on the short-circuit ratio model at the bus of the new energy station, a short-circuit ratio model at the grid-connected bus of the new energy station after the distributed phase modifier or grid forming type energy storage is configured and its constraint condition are established.

[0089] Specifically, step 2 includes:

[0090] Step 2.1, a short-circuit ratio model at the bus i of the new energy station is established, which satisfies the following relationship:

[0091]

[0092] In the formula, is the nominal voltage of the bus i; is the actual operating voltage of the bus i; is the actual apparent power injected by the new energy at the bus i, and the subscript RE represents the new energy power generation equipment / station; is a complex power conversion factor between bus i and bus j, reflecting the phase and amplitude difference between the electrical quantities at the grid-side access point of each new energy power generation device / grid-connected point of each new energy power station, are the conjugate complex numbers of the actual operating voltages at bus i and bus j, respectively; is the AC grid node equivalent impedance matrix at the bus is the element in the i-th row and i-th column of the matrix, and the element in the i-th row and j-th column of the matrix.

[0093] The new energy multi-station short-circuit ratio model shown as formula (5) is adopted in the application, which is a simplified and linearized model. Compared with the nonlinear short-circuit ratio model, the short-circuit ratio calculation has higher accuracy, and the linear programming optimization problem considering the short-circuit ratio constraint can be modeled and solved, and the optimal planning of the short-circuit ratio constrained network type energy storage and distributed phase modifier can be realized.

[0094] In the non-limiting preferred embodiment, the new energy station bus includes a new energy station grid-connected bus and a new energy station machine terminal bus. Subscript S and subscript G represent the new energy grid-connected bus and the new energy machine terminal bus, respectively.

[0095] Step 2.2, the short-circuit capacity at the new energy station grid-connected bus and the active power injected by the grid-connected bus are collected, and a multi-station short-circuit ratio model at the new energy station grid-connected bus is established based on the multi-station short-circuit ratio model at the new energy station bus;

[0096] Specifically, if X / R>10 and the voltage phase angles of each new energy station are assumed to be similar, and further considering that the voltages of each node in the system are close to the rated value, and ignoring the reactive power output of the grid-connected point new energy station, then the MRSCR at the new energy station grid-connected bus i is S,i satisfies the following relationship:

[0097]

[0098] In the formula, S aci is the short-circuit capacity at the grid-connected bus i; P REi is the active power injected by the grid-connected bus i, P RE,j is the active power injected by the grid-connected bus j; is the active power conversion factor between the grid-connected bus i and the grid-connected bus j before the distributed phase modifier or the network type energy storage is configured, reflecting the amplitude difference of the equivalent impedance of each new energy power generation device grid-side access point or new energy station grid-connected point.

[0099] Step 2.3, based on the constraint of the active power conversion factor between the grid-connected bus i and j after the configuration of the distributed phase modifier or the grid-forming energy storage, a multi-station short-circuit ratio model at the grid-connected bus of the new energy station after the configuration of the distributed phase modifier or the grid-forming energy storage is established;

[0100] If the grid structure and the active power at the grid-connected point of the new energy station are basically unchanged after the configuration of the distributed phase modifier or the grid-forming energy storage. At this time, considering the impedance parallel characteristic, the active power conversion factor between the grid-connected bus i and j before the configuration of the distributed phase modifier or the grid-forming energy storage is greater than the active power conversion factor between the grid-connected bus i and j after the configuration of the distributed phase modifier or the grid-forming energy storage. At this time, the short-circuit capacity S aci ′ at the grid-connected bus i of the new energy station after the configuration of the distributed phase modifier or the grid-forming energy storage satisfies the following relationship:

[0101]

[0102] In the formula, λ′ ij is the active power conversion factor between the grid-connected bus i and j after the configuration of the distributed phase modifier or the grid-forming energy storage;

[0103] The multi-station short-circuit ratio model MRSCR at the grid-connected bus i of the new energy station after the configuration of the distributed phase modifier or the grid-forming energy storage satisfies the following relationship: S,i ′:

[0104]

[0105] The multi-station short-circuit ratio model at the grid-connected bus of the new energy station after the configuration of the distributed phase modifier or the grid-forming energy storage is an inequality model with a lower bound. The present application realizes the conversion from the equality constraint of the short-circuit ratio, the short-circuit capacity, the active power and the active power factor after the configuration of the distributed phase modifier and the grid-forming energy storage to the inequality constraint of the short-circuit ratio after the configuration, the short-circuit capacity after the configuration, the short-circuit ratio before the configuration and the short-circuit capacity, which simplifies the calculation amount of the active power and the active power factor under different configuration conditions, and converts the equality model of the original multi-station short-circuit ratio model into an inequality model with a lower bound, so that it can be added to the optimal configuration model in the subsequent process, and the optimal configuration mode can be realized through optimization to achieve the minimum multi-station short-circuit ratio which meets the requirements.

[0106] Step 2.4, taking the multi-station short-circuit ratio at the grid-connected bus of the new energy station after the configuration of the distributed phase modifier or the grid-forming energy storage not less than the lower limit of the multi-station short-circuit ratio at the grid-connected bus of the new energy station as the constraint condition of the multi-station short-circuit ratio model at the grid-connected bus of the new energy station after the configuration of the distributed phase modifier or the grid-forming energy storage.

[0107] Multi-station short circuit ratio (MRSCR) of new energy station grid-connected bus after configuring distributed phase modifier or grid-forming energy storage S,i Lower limit of multi-station short circuit ratio (MRSCR) of new energy station grid-connected bus S,min The multi-station short circuit ratio model of new energy station grid-connected bus after configuring distributed phase modifier or grid-forming energy storage and its constraint condition meet the following relationship:

[0108]

[0109] Step 3, based on the short circuit capacity model of new energy station grid-connected bus after configuring distributed phase modifier or grid-forming energy storage and the multi-station short circuit ratio model of new energy station grid-connected bus and its constraint condition, establish the multi-station short circuit ratio constraint of new energy after configuring distributed phase modifier or grid-forming energy storage.

[0110] The constraint condition of multi-station short circuit ratio of new energy after configuring distributed phase modifier or grid-forming energy storage meets the following relationship:

[0111]

[0112] The amplitude of short circuit current at the bus of new energy station after configuring distributed phase modifier or grid-forming energy storage meets the following relationship:

[0113]

[0114] Further, the multi-station short circuit ratio constraint of new energy after configuring distributed phase modifier or grid-forming energy storage meets the following relationship:

[0115]

[0116] In the formula, Ifb ,e,i , I cn,e,i are the short circuit currents provided by the grid-forming energy storage e and the distributed phase modifier e to bus i, respectively, e∈cn, e∈fb are voltage source type units of type grid-forming energy storage or distributed phase modifier e; θ cn-sys,e,i is the corresponding phase angle difference of configuring grid-forming energy storage e or distributed phase modifier e.

[0117] Under the premise that the short circuit capacity at the grid-connected bus i of new energy station before configuring distributed phase modifier or grid-forming energy storage, the short circuit current I sys,i provided by the system and the multi-station short circuit ratio are known, the multi-station short circuit ratio constraint of new energy after optimizing the configuration of distributed phase modifier or grid-forming energy storage is only related to the short circuit current I fb,e,i , I cn,e,i , θ cn-sys,e,i provided by the distributed phase modifier or grid-forming energy storage when three-phase short circuit fault occurs at the grid-connected bus of new energy station.

[0118] In a non-restrictive preferred embodiment, the short-circuit current I provided by the grid-forming energy storage e, the distributed phase modifier e to the bus i is calculated fb,e,i or I cn,e,i When the short-circuit current is calculated, the internal potential of the distributed phase modifier or the grid-forming energy storage e is calculated by setting the internal potential of all the remaining voltage source type units in the system except the distributed phase modifier or the grid-forming energy storage e to zero. The fault current provided by the unit e to the bus j is calculated by the short-circuit current calculation program As shown in the following formula:

[0119]

[0120] In the formula, Y n×d is the admittance matrix of n rows by d columns.

[0121] Step 4, taking the optimal comprehensive cost of configuring the distributed phase modifier or the grid-forming energy storage as the objective function; the objective function, the number constraint of configuring the distributed phase modifier or the grid-forming energy storage, the capacity constraint, and the new energy multi-field station short-circuit ratio dynamic constraint after configuring the distributed phase modifier or the grid-forming energy storage, together constitute the optimization configuration model of the distributed phase modifier or the grid-forming energy storage.

[0122] Specifically, step 4 includes:

[0123] Step 4.1, establishing the number constraint and capacity constraint of configuring the distributed phase modifier or the grid-forming energy storage;

[0124] The number constraint and capacity constraint of configuring the distributed phase modifier or the grid-forming energy storage meet the formulas (14) and (15) respectively:

[0125]

[0126] In the formula, N fd,i , N cn,i are the upper limit of the number of distributed phase modifiers or grid-forming energy storages configured at the grid-connected bus i; Q fd , Q cn are the capacity upper limit of the distributed phase modifier or the grid-forming energy storage configured; y fd,e,i , y cn,e,i is whether the distributed phase modifier or the grid-forming energy storage e is configured at the grid-connected bus i, which is a 0-1 state quantity in a non-restrictive preferred embodiment; Q fd,e,i , Q cn,e,i is the capacity of the distributed phase modifier or the grid-forming energy storage e configured at the grid-connected bus i.

[0127] Step 4.2, based on the quantity constraint and capacity constraint of configuring the distributed phase modifier or grid-forming energy storage, an integrated cost model of configuring the distributed phase modifier or grid-forming energy storage is established, and the integrated cost optimization of configuring the distributed phase modifier or grid-forming energy storage is taken as the objective function;

[0128] Specifically, the integrated cost model C includes the purchase cost and operation cost of the distributed phase modifier or grid-forming energy storage, and satisfies the formula (16) to formula (20) as shown:

[0129] C = C 0,fd +C m,fd +C 0,cn +C m,cn (16)

[0130]

[0131] In the formula, C 0,fd , C m,fd are the configuration cost and operation and maintenance cost of the distributed phase modifier respectively; C 0,cn , C m,cn are the configuration cost and operation and maintenance cost of the grid-forming energy storage respectively; c 0,fd , c 1,fd , c 2,fd are the configuration cost, loss cost and manual operation and maintenance cost of a single distributed phase modifier respectively; c 0,cn , c 1,cn , c 2,cn are the configuration cost, loss cost and manual operation and maintenance cost of a single grid-forming energy storage respectively.

[0132] Step 4.3, based on the quantity constraint of configuring the distributed phase modifier or grid-forming energy storage, the short-circuit ratio constraint of the new energy multi-station after configuring the distributed phase modifier or grid-forming energy storage is dynamically processed, and the short-circuit ratio dynamic constraint of the new energy multi-station after configuring the distributed phase modifier or grid-forming energy storage is obtained.

[0133] The short-circuit ratio dynamic constraint of the new energy multi-station after configuring the distributed phase modifier or grid-forming energy storage satisfies the following relationship:

[0134]

[0135] The obtained short-circuit ratio constraint of the new energy multi-station after configuring the distributed phase modifier or the grid-forming energy storage is an inequality constraint, which represents a minimum short-circuit ratio constraint from the perspective of system topology and system parameters, and the number constraint of the distributed phase modifier or the grid-forming energy storage represents a minimum number and economic configuration of the distributed phase modifier or the grid-forming energy storage to meet the short-circuit ratio constraint of the new energy multi-station. Based on the number constraint of the distributed phase modifier or the grid-forming energy storage, the short-circuit ratio constraint of the new energy multi-station after configuring the distributed phase modifier or the grid-forming energy storage is dynamically processed to obtain the short-circuit ratio dynamic constraint of the new energy multi-station after configuring the distributed phase modifier or the grid-forming energy storage, so as to realize the minimum number and capacity of the distributed phase modifier and the grid-forming energy storage to meet the short-circuit ratio constraint of the new energy multi-station from two different ways. In the method provided in the application, the minimum short-circuit ratio constraint of the new energy multi-station is not realized by a complex nonlinear multi-station short-circuit ratio constraint model, but is realized based on a simplified and linearized multi-station short-circuit ratio model, so as to ensure high accuracy of the multi-station short-circuit ratio calculation, and convert the nonlinear programming problem of the optimal planning model of the grid-forming energy storage and the distributed phase modifier under the multi-station short-circuit ratio constraint into a linear programming problem for linearized solution, so as to realize the optimal planning of the grid-forming energy storage and the distributed phase modifier under the multi-station short-circuit ratio constraint.

[0136] Step 4.4, the objective function and the number constraint and capacity constraint of the distributed phase modifier or the grid-forming energy storage, and the short-circuit ratio dynamic constraint of the new energy multi-station after configuring the distributed phase modifier or the grid-forming energy storage, jointly constitute the optimal configuration model of the distributed phase modifier or the grid-forming energy storage.

[0137] Step 5, iteratively solving the optimal configuration model of the distributed phase modifier or the grid-forming energy storage to obtain the configuration result of the grid-forming energy storage and the distributed phase modifier under the short-circuit ratio constraint.

[0138] Specifically, as shown in Figure 3 , first, the configuration optimization problem of the distributed phase modifier and the grid-forming energy storage is converted into the optimization problem of the start mode of the distributed phase modifier and the grid-forming energy storage in the form of pre-entering the basic parameters of the power grid into the PSD-BPA software; second, the short-circuit current calculation program and the short-circuit ratio calculation program without the grid-forming energy storage in the PSD-BPA software are called to calculate the short-circuit current and the short-circuit ratio under different unit start modes, and the S aci , MRSCR S,i data calculated in advance under the full shutdown mode of the distributed phase modifier and the grid-forming energy storage, and the I sys,i , I fb,e,i , I cn,e,i , θ cn-sys,e,iData, reduce the variables to be determined to y cn,e,i 、y fb,e,i Finally, the main program of the optimization configuration model is constructed based on the Matlab software YALMIP toolkit, and the IPOPT solver is called to solve the problem, thereby realizing the optimal configuration of distributed phase-shifting cameras and grid-type energy storage.

[0139] This embodiment uses Figure 4 Taking the actual simulation system shown in the figure as an example, the implementation steps of a method for optimizing the configuration of grid-type energy storage and distributed phase-converter considering the linearization constraint of short-circuit ratio of multiple stations are explained:

[0140] 1. Establish basic grid parameters

[0141] For a certain actual "Shagohuang" photovoltaic base, the UHVDC transmission system is as follows: Figure 4 As shown, the Z converter station at the sending end is connected to the main grid at the sending end through three 750 kV lines. The UHV DC rated power is 8000MW and the rated voltage is ±800kV. The nearby supporting thermal power of 2640MW and the supporting "Shagohuang" photovoltaic power of 6000MW are collected to the G substation (35kV / 330kV / 750kV three-level boosting), and supporting construction of 600MW energy storage (of which 100MW is grid-type energy storage). It is planned to build 500MW grid-type energy storage and up to 24 50MVar distributed phase-shifting units; the maximum output simultaneity of supporting new energy is 95%; the grid-type energy storage is connected to the 35kV bus through a 0.4kV / 35kV step-up transformer; the distributed phase-shifting unit is connected to the 35kV bus through a 10kV / 35kV step-up transformer; the grid structure in the collection station is as follows Figure 5 As shown in Table 1, the planning, loss, and operation and maintenance costs of a single device are shown in Table 1, and the main parameters of the power grid structure are shown in Table 2.

[0142] Table 1 Planning, loss, and operation and maintenance costs of a single device

[0143]

[0144] Table 2 Main parameters of power grid structure

[0145]

[0146] At the same time, when the critical short-circuit ratio RSCRG,min of the new energy station terminal is 1.5 under unit voltage, the corresponding critical short-circuit ratio RSCR at the grid connection point is S,min The calculation method is as follows:

[0147]

[0148] Combined with the relevant requirements of the national standard GB / T 40594 on the critical short circuit ratio of the new energy station terminal, the critical short circuit ratio RSCR of the new energy station terminal G,minThe recommended critical multi-field short-circuit ratio MRSCR of the new energy station grid connection point is taken 1.5 with a certain engineering margin S,min The recommended critical multi-field short-circuit ratio MRSCR of the new energy station grid connection point is taken 1.70.

[0149] 2. Generate planning basic parameters through PSD-BPA.

[0150] The electromechanical transient simulation model of the system is established on the PSD-BPA power system analysis software platform, the multi-field short-circuit ratio and short-circuit capacity of each grid connection point before the access of all distributed phase modulators and network-forming energy storage are evaluated, and the results are shown in Table 3.

[0151] Table 3 Minimum multi-field short-circuit ratio and minimum short-circuit capacity of grid connection point

[0152]

[0153] In the full-on mode of new energy generation, network-forming energy storage and distributed phase modulator, and in the charging state of network-forming energy storage (low system short-circuit capacity, low short-circuit capacity improved by network-forming energy storage), considering the number of distributed phase modulators or network-forming energy storage configured at each grid connection point i, the capacity is evenly distributed as much as possible (N fd,i , N cn,i is 1, Q fd,e,i is 50 MVar, and Q cn,e,i is 16.67 MW), the short-circuit current complex matrix of each voltage source type generator and the main network side at each grid connection point (24+30+36) x 36 is formed, and the multi-field short-circuit ratio and short-circuit capacity of each grid connection point are counted as shown in the following table.

[0154] Table 4 Short-circuit ratio and short-circuit capacity of grid connection point under different configuration conditions

[0155]

[0156] It can be seen that with the increase of the configuration capacity of distributed phase modulator and network-forming energy storage and the improvement of the overcurrent capacity of network-forming energy storage, the minimum short-circuit ratio and minimum short-circuit capacity of each grid connection point gradually increase. When the configuration capacity of network-forming energy storage is 500 MW and the configuration capacity of distributed phase modulator is 1200 MVar, the multi-field short-circuit ratio of each grid connection point is much larger than the requirement, and in order to ensure the economy of the planning, the optimal configuration of distributed phase modulator and network-forming energy storage must be realized. Considering that the construction and operation cost of distributed phase modulator is high, network-forming energy storage equipment with high overcurrent capacity should be used, and only network-forming energy storage with three times overcurrent capacity is considered in the future.

[0157] 3. Optimal configuration model is built to realize the optimal configuration of network-forming energy storage and distributed phase modulator.

[0158] The upper limit N fd,i of the number of distributed phase modulators configured at each grid connection point i is 1 unit, and Qfd,e,i For 50MVar, the network configuration type energy storage scenario is as follows:

[0159] Scenario 1: Network configuration type energy storage configuration number limit N cn,i 1 unit, Q cn,e,i 16.66MW;

[0160] Scenario 2: Network configuration type energy storage configuration number limit N cn,i 1 unit, Q cn,e,i 20MW;

[0161] Scenario 3: Network configuration type energy storage configuration number limit N cn,i 2 units, Q cn,e,i 16.66MW;

[0162] Scenario 4: Network configuration type energy storage configuration number limit N cn,i 2 units, Q cn,e,i 20MW;

[0163] Scenario 5: Network configuration type energy storage configuration number limit N cn,i 2 units, Q cn,e,i 27.76MW;

[0164] Scenario 6: Network configuration type energy storage configuration number limit N cn,i 3 units, Q cn,e,i 16.66MW.

[0165] At this time, the planning results under each scenario are shown in the following table:

[0166] Table 5: Planning results under each scenario

[0167]

[0168] As can be seen from Table 5, as the voltage source type unit capacity increases, the minimum short circuit ratio and the minimum short circuit capacity of each grid connection point gradually increase; the more the number of distributed phase modulation machines configured, the higher the comprehensive cost; simply increasing the configured network type energy storage capacity, the comprehensive cost shows a decreasing first and then increasing trend. When the configured network type energy storage capacity is 420MW, the distributed phase modulation machine is 17 units, and the capacity is 850MVar, the short circuit ratio of each grid connection point multi-station meets the requirements, and the optimal configuration of distributed phase modulation machine and network type energy storage is realized.

[0169] Table 6: Short circuit ratio and short circuit capacity of each scenario under different short circuit ratio calculation methods

[0170]

[0171] Based on the method and the short-circuit ratio calculation method of multi-station of new energy, the short-circuit ratio and short-circuit capacity of multi-station of each planning scenario are obtained as shown in Table 6. As can be seen from Table 6, the minimum short-circuit ratio and minimum short-circuit capacity of each grid-connected point calculated by the method and the short-circuit ratio calculation method of multi-station of new energy have small deviation, the short-circuit ratio calculation result of the method is only 0.53% to 1.88% larger, the short-circuit capacity calculation result is only 0.86% to 3.53% larger, the conservatism of the result meets the needs of engineering application, and the effectiveness and accuracy of the method are verified.

Claims

1. A method for configuring grid-type energy storage and distributed phase regulators under short-circuit ratio constraints, applicable to new energy stations including grid-type energy storage or distributed phase regulators, characterized in that: include: Obtain the short-circuit current at the busbar of the new energy station and establish a short-circuit capacity model for the grid-connected busbar of the new energy station after configuring distributed phase-converters or grid-connected energy storage; Establish a short-circuit ratio model for the busbar of a new energy station; collect the short-circuit capacity and active power injected into the grid-connected busbar of the new energy station, and establish a short-circuit ratio model for the grid-connected busbar of the new energy station based on the short-circuit ratio model of the busbar of the new energy station Satisfies the following relationship: Where, Grid-connected bus i Short-circuit capacity; Grid-connected bus i The injected active power, Grid-connected bus j Injected active power; It is a grid-connected busbar before configuring distributed phase regulator or grid-connected energy storage. i and j The active power conversion factor of the power between 、 is the equivalent impedance matrix of the AC grid node at the busbar No. i Row, No. i The elements of the column and i Row, No. j Column elements; Based on the configuration of distributed phase regulator or grid-type energy storage to the grid-connected bus i and j The constraint of the active power conversion factor between them is used to establish the short-circuit ratio model of the grid-connected busbar of the new energy station after the distributed phase-shifting or grid-type energy storage is configured; the short-circuit ratio of the grid-connected busbar of the new energy station after the distributed phase-shifting or grid-type energy storage is not less than the lower limit of the short-circuit ratio of the grid-connected busbar of the new energy station after the distributed phase-shifting or grid-type energy storage is used as the constraint condition of the short-circuit ratio model of the grid-connected busbar of the new energy station after the distributed phase-shifting or grid-type energy storage is configured; the short-circuit ratio model of the grid-connected busbar of the new energy station after the distributed phase-shifting or grid-type energy storage is configured And its constraints satisfy the following relationship: ， Where, Grid-connected busbar for new energy stations equipped with distributed phase regulators or grid-type energy storage i Short-circuit capacity at The lower limit of the short-circuit ratio at the grid-connected busbar of the new energy station; Based on the short-circuit capacity model and short-circuit ratio model at the grid-connected busbar of the new energy station after the configuration of distributed phase-converter or grid-connected energy storage, and their constraints, the short-circuit ratio constraint of the new energy multi-station after the configuration of distributed phase-converter or grid-connected energy storage is established, satisfying the following relationship: Where, Grid-connected busbar for new energy stations The amplitude of the nominal voltage at ; Busbar for new energy stations The amplitude of the short-circuit current at is the system baseline capacity; Where, 、 Grid-type energy storage e , Distributed Phase Regulator e Towards busbar i Provides short-circuit current, 、 They are voltage source units of grid-type energy storage or distributed phase regulators. e ; To configure grid-type energy storage e or distributed phase regulator e The corresponding phase angle difference satisfies ; Representative bus i Voltage source unit with grid-type energy storage e The phase angle, The phase angle of the short-circuit current supplied to the AC system, Provides busbars for AC systems to new energy stations i The short-circuit current provided; The objective function is to optimize the comprehensive cost of configuring distributed phase-converters or grid-type energy storage. This objective function, along with the quantity and capacity constraints of the distributed phase-converters or grid-type energy storage, and the dynamic constraints on the short-circuit ratio of multiple renewable energy stations after configuring the distributed phase-converters or grid-type energy storage, together constitute an optimal configuration model for the distributed phase-converters or grid-type energy storage. The optimal configuration model of distributed phase-converter or grid-type energy storage is solved iteratively to obtain the configuration results of grid-type energy storage and distributed phase-converter under short-circuit ratio constraints.

2. The method for configuring grid-type energy storage and distributed phase regulator under short-circuit ratio constraints according to claim 1, characterized in that: Obtain the short-circuit current at the busbar of the new energy station and establish a short-circuit capacity model for the grid-connected busbar of the new energy station after configuring distributed phase-converters or grid-connected energy storage, including: Collect the short-circuit current provided to the bus by grid-type energy storage, distributed phase regulators, and AC systems, and calculate the vector of the short-circuit current at the bus of the new energy station; Establish the amplitude and phase angle constraints of the short-circuit current provided by the grid-type energy storage to the busbar; Based on the amplitude and phase constraints of the short-circuit current provided by the grid-type energy storage to the bus, the amplitude of the short-circuit current at the new energy station bus is calculated; Based on the relationship between the short-circuit capacity at the grid-connected busbar of the new energy station after the configuration of distributed phase-converter or grid-type energy storage and the short-circuit current at the busbar of the new energy station, a short-circuit capacity model at the grid-connected busbar of the new energy station after the configuration of distributed phase-converter or grid-type energy storage is established.

3. The method for configuring grid-type energy storage and distributed phase regulator under short-circuit ratio constraints according to claim 2, characterized in that: The short-circuit capacity model at the grid-connected busbar of a new energy station equipped with distributed phase-converters or grid-connected energy storage satisfies the following relationship: Where, Grid-connected busbar for new energy stations equipped with distributed phase regulators or grid-type energy storage i Short-circuit capacity at Grid-connected busbar for new energy stations i The amplitude of the nominal voltage at ; Busbar for new energy stations The amplitude of the short-circuit current at This is the system baseline capacity.

4. The method for configuring grid-type energy storage and distributed phase regulator under short-circuit ratio constraints according to claim 1, characterized in that: The vectors of short-circuit currents at the busbars of renewable energy stations containing grid-type energy storage or distributed cameras include: the short-circuit current provided by the grid-type energy storage to the busbars of renewable energy stations, the short-circuit current provided by the distributed phase-shifting camera to the busbars of renewable energy stations, and the short-circuit current provided by the AC system to the busbars of renewable energy stations; Calculate the short-circuit current provided by the grid-type energy storage to the new energy station bus or the short-circuit current provided by the distributed phase-shifting machine to the new energy station bus, including: clearing the internal potential of all voltage source units in the system except the distributed phase-shifting machine or grid-type energy storage to zero, and using the internal potential of the distributed phase-shifting machine or grid-type energy storage as the Calculate with the admittance matrix and satisfy the following relationship: Where, for n Row× d The admittance matrix of the columns, n is the number of new energy station busbars, d is the number of distributed phase regulators or grid-type energy storage, 、……、 、……、 Distributed phase regulator or grid-type energy storage To the new energy station bus 1, ...new energy station bus 、……New energy station busbar n Provides short-circuit current.

5. The method for configuring grid-type energy storage and distributed phase regulator under short-circuit ratio constraints according to claim 1, characterized in that: The objective function is to optimize the comprehensive cost of configuring distributed phase-converter or grid-type energy storage. This objective function, along with the quantity and capacity constraints of the distributed phase-converter or grid-type energy storage, and the dynamic constraints on the short-circuit ratio of multiple renewable energy stations after configuring the distributed phase-converter or grid-type energy storage, together constitute an optimal configuration model for the distributed phase-converter or grid-type energy storage, including: Establish quantity constraints and capacity constraints for configuring distributed phase-shifting or grid-type energy storage; Based on the quantity and capacity constraints of configuring distributed phase-converter or grid-type energy storage, a comprehensive cost model for configuring distributed phase-converter or grid-type energy storage is established, with the optimal comprehensive cost of configuring distributed phase-converter or grid-type energy storage as the objective function; Based on the quantity constraint of distributed phase-converter or grid-type energy storage, the short-circuit ratio constraint of multiple renewable energy stations after the distributed phase-converter or grid-type energy storage is dynamically processed to obtain the dynamic short-circuit ratio constraint of multiple renewable energy stations after the distributed phase-converter or grid-type energy storage is configured; The objective function, the quantity constraints and capacity constraints of configuring distributed phase-modulating phases or grid-type energy storage, and the dynamic constraints of the short-circuit ratio of new energy multiple stations after configuring distributed phase-modulating phases or grid-type energy storage together constitute the optimal configuration model of distributed phase-modulating phases or grid-type energy storage.

6. The method for configuring grid-type energy storage and distributed phase regulators under short-circuit ratio constraints according to claim 5, characterized in that: The quantity and capacity constraints of distributed phase-converters or grid-type energy storage are configured to satisfy the following relationships: Where, 、 Grid-connected bus i The upper limit of the number of distributed phase regulators or grid-type energy storage configurations; 、 They are the upper limits of the capacity of distributed phase-shifting or grid-type energy storage configurations; 、 Grid-connected bus i Whether to configure distributed phase regulator or grid-type energy storage e , using 0-1 state quantity; 、 Grid-connected bus i Distributed phase regulators or grid-type energy storage configured at e capacity.

7. The method for configuring grid-type energy storage and distributed phase regulators under short-circuit ratio constraints according to claim 5, characterized in that: The dynamic constraint on the short-circuit ratio of multiple renewable energy stations after configuring distributed phase-converting devices or grid-type energy storage satisfies the following relationship: Where, 、 Grid-connected bus i Whether to configure distributed phase regulator or grid-type energy storage e , is a 0-1 state quantity; 、 Grid-type energy storage e , Distributed Phase Regulator e Towards busbar i Provides short-circuit current, 、 They are voltage source units of grid-type energy storage or distributed phase regulators. e ; To configure grid-type energy storage e or distributed phase regulator e The corresponding phase angle difference satisfies ; Representative bus i Voltage source unit with grid-type energy storage e The phase angle, The phase angle of the short-circuit current supplied to the AC system; The lower limit of the short-circuit ratio at the grid-connected busbar of the new energy station; Grid-connected bus i Short-circuit capacity; is the short-circuit ratio at the grid-connected busbar of the new energy station; Provides busbars for AC systems to new energy stations i Provides short-circuit current.

8. A system for configuring a grid-type energy storage and distributed phase condenser under short-circuit ratio constraints, suitable for a new energy station including a grid-type energy storage or a distributed phase condenser, and used to implement the method for configuring a grid-type energy storage and distributed phase condenser under short-circuit ratio constraints as described in any one of claims 1 to 7, characterized in that: include: Short-circuit ratio constraint establishment module, optimization configuration model module, optimization configuration module; A short-circuit ratio constraint establishment module is used to obtain the short-circuit current at the busbar of a new energy station and establish a short-circuit capacity model at the grid-connected busbar of a new energy station after configuring distributed phase-converters or grid-type energy storage; based on the short-circuit ratio model at the busbar of a new energy station, a short-circuit ratio model and its constraints at the grid-connected busbar of a new energy station after configuring distributed phase-converters or grid-type energy storage are established; based on the short-circuit capacity model and the short-circuit ratio model at the grid-connected busbar of a new energy station after configuring distributed phase-converters or grid-type energy storage, a short-circuit ratio constraint for multiple new energy stations after configuring distributed phase-converters or grid-type energy storage is established; An optimization configuration model module is used to optimize the comprehensive cost of configuring distributed phase-converters or grid-type energy storage as the objective function. This objective function, along with the quantity and capacity constraints of the distributed phase-converters or grid-type energy storage, and the dynamic constraints on the short-circuit ratio of multiple renewable energy stations after configuring the distributed phase-converters or grid-type energy storage, together constitute an optimization configuration model for the distributed phase-converters or grid-type energy storage. The optimization configuration module is used to iteratively solve the optimization configuration model of distributed phase-converter or grid-type energy storage, and obtain the configuration results of grid-type energy storage and distributed phase-converter under the short-circuit ratio constraint.

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