A current-limiting control method and system based on energy storage inverter voltage source operation

Abstract

This invention discloses a current-limiting control method and system based on voltage-source operation of an energy storage inverter, wherein the method includes: determining the maximum output power P of the energy storage device through the energy storage unit. max The output phase angle difference limit value δ is derived based on the power angle curve relationship. lim According to the phase angle difference limiting value δ of the energy storage inverter output. lim Calculate the maximum value of the d-axis component i of the current-limiting loop. d qref(lim) At the same time, ensure that the output current does not exceed the preset maximum current value, and for the maximum value i of the q-axis component. q qref(lim) Limitations are implemented by introducing a phase angle difference limiter in the power loop and a q-axis current limiter in the current loop. Based on the output power characteristics of the upstream distributed power source and considering overcurrent protection under grid-side low-voltage ride-through conditions, this invention ensures the stable and safe operation of the energy storage inverter by setting limiting control strategies in the power and current loops.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of power electronics, and particularly relates to a current-limiting control method and system based on voltage source operation of an energy storage inverter. BACKGROUND

[0002] The energy storage inverter re-distributes power and energy flow in time and space, and can cope with power fluctuation and power supply quality decline caused by high penetration of distributed power into the power grid.

[0003] As a highly flexible and controllable energy source, the energy storage device has faster response speed and has strong advantages in dealing with the volatility of new energy. When the energy storage device is in voltage source operation, it can provide active support for voltage / frequency of the power grid, and plays a huge role in the safe and stable operation of the power grid.

[0004] At the same time, as a highly flexible, adjustable and controlled equipment in terms of power and energy, the energy storage can effectively improve the bearing and consumption level of distributed photovoltaic and support the construction of new power distribution systems. Energy storage and new energy inverter generation technology are both important interfaces of power electronic equipment, and can realize functions such as peak clipping, valley filling and tide optimization.

[0005] With the increasing degree of power electronicization of the grid and load equipment, the strength of the grid is declining. The common grid-connected inverter is unstable under a weak grid and cannot stably deliver power. Therefore, the energy storage inverter in voltage source operation is considered to provide stable voltage and frequency support for the grid. However, the energy storage inverter in voltage source operation also has some problems. When the energy storage inverter is in voltage source operation, it is often regarded as a voltage source with internal resistance, and its output current is determined by the load. However, the current carrying capacity of the switching device is limited and cannot have the current carrying capacity of a traditional motor. Therefore, the overcurrent technology of the energy storage inverter can be further explored, combined with the traditional current loop current limiting control technology, to make the energy storage inverter adapt to the processing fluctuation characteristics of new energy and meet the needs of the construction of new power systems.

[0006] In the existing voltage source control strategy of the energy storage inverter, considering the grid low voltage ride through grid side fault overcurrent problem, in order to protect the energy storage inverter, the current loop limiting control strategy and the cutting strategy are often used. When the output current of the inverter exceeds the current that can be carried by the switching device, the traditional control strategy often considers limiting the current loop d-axis and q-axis components. However, directly limiting the d-axis and q-axis components often causes the power loop and the voltage loop to fall off, and the voltage source type operation cannot be restored normally after the grid side fault is over.

[0007] The Chinese patent with publication number CN117458599A also discloses a current limiting control method for voltage source operation of an energy storage inverter, including the following steps: obtaining the rated voltage and current of the inverter, and setting the maximum current that the energy storage inverter can bear; introducing a current limiter, limiting the d and q axis current command values in the dq coordinate system respectively; introducing a phase-locked loop (PLL) element to track the q-axis voltage of the distribution network bus, and when the q-axis voltage is 0, calculating the frequency and phase angle of the distribution network bus at this time; calculating the actual output frequency and phase angle of the inverter according to the droop active power-frequency relationship; putting in the phase angle switching element, when the current limiter is not triggered, the frequency and phase angle of the energy storage inverter output are kept, and when the current limiter is triggered, the frequency and phase angle are switched to the frequency and phase angle of the distribution network bus; after triggering the current limiter, it is judged whether the output frequency of the energy storage inverter restores to within the threshold, and if it restores, the frequency and phase angle of the inverter output are switched back to the actual output frequency and phase angle. The current limiting control mechanism of the invention sets the limiting amplitude value based on the rated current and maximum bearing current of the inverter, adopts a static limiting measure, mainly relies on the pre-set maximum current limit, and cannot quickly respond to changes in complex power grids or dynamic load changes, and cannot flexibly respond to current fluctuations under different load conditions. SUMMARY

[0008] To solve the above-mentioned problems of the prior art, such as the output fluctuation of new energy and the adverse effects of low voltage fault on the energy storage converter, the present application provides a current limiting control method and system based on voltage source operation of an energy storage inverter, which sets a limiting control strategy in the power loop and current loop according to the output power characteristics of the input front-stage distributed power source and considering the over-current protection under the low voltage ride-through condition of the grid side, to ensure the stable and safe operation of the energy storage inverter.

[0009] To solve the above-mentioned technical problems, the present application provides a current limiting control method based on voltage source operation of an energy storage inverter, including the following steps:

[0010] Determine the maximum output power P of the energy storage device through the energy storage unit max , derive the output phase angle difference limiting value δ according to the power angle curve relationship lim .

[0011] According to the phase angle difference limiting value δ of the energy storage inverter output lim , calculate the maximum value i of the d-axis component of the limiting current loop d qref(lim) At the same time, guarantee that the output current does not exceed the pre-set maximum current, limit the maximum value i of the q-axis component q qref(lim) .

[0012] The phase angle difference limiter is introduced into the power loop to limit the phase angle difference, and the q-axis current limiter is introduced into the current loop to limit the q-axis current.

[0013] Preferably, the output power angle relationship formula of the voltage source type operation control energy storage inverter is specifically:

[0014]

[0015] In the formula, P o is the active power output by the energy storage inverter; V g is the grid voltage; V ref is the output voltage of the energy storage inverter; δ is the difference between the phase angle output by the power loop and the grid-side phase angle obtained by phase locking; X g is the grid line impedance, which is considered to be inductive at this moment.

[0016] The phase angle difference limiting value δ is derived according to the maximum output power of the energy storage device lim Specifically:

[0017]

[0018] In the formula, δ lim is the phase angle difference limiting value; P max is the maximum power output by the energy storage inverter; X g is the grid voltage; X g is the grid line impedance.

[0019] Preferably, the d-axis component limiting value i d qref(kim) of the current loop of the voltage source type operation control energy storage inverter is specifically:

[0020]

[0021] In the formula, i d qref(lim) is the d-axis component limiting value of the current loop of the voltage source type operation control energy storage inverter; V g is the grid voltage; δ kim is the phase angle difference limiting value; X v is the virtual inductance introduced by the voltage loop.

[0022] The q-axis component limiting value i q qref(lim) of the current loop of the voltage source type operation control energy storage inverter is specifically:

[0023]

[0024] In the formula, i q qref(lim)The current loop q-axis component limit value of the voltage source type operation control energy storage inverter max The maximum current that the energy storage inverter can bear d qref(lim) The current loop d-axis component limit value of the voltage source type operation control energy storage inverter

[0025] Preferably, the phase angle limit calculation formula of the phase angle difference limiter is specifically as follows:

[0026]

[0027] In the formula, The phase angle limit of the phase angle difference limiter; δ is the difference between the phase angle output by the power loop and the grid side phase angle obtained by phase locking; δ lim The phase angle difference limit value.

[0028] The current limit calculation formula of the q-axis current limiter is specifically as follows:

[0029]

[0030] In the formula, The current limit of the q-axis current limiter; i q qref The current q-axis component output by the voltage loop; i q qref(lim) The current loop q-axis component limit value.

[0031] In another aspect, the application provides a current limiting control system based on the voltage source type operation of the energy storage inverter, which comprises a phase angle difference derivation module, a current limit calculation module and a limiter introduction module.

[0032] The phase angle difference derivation module is used to determine the maximum output power P max of the energy storage device through the energy storage unit, and derive the output phase angle difference limit value δ lim according to the power angle curve relationship.

[0033] The current limit calculation module is used to calculate the maximum value i lim of the d-axis component of the current loop according to the phase angle difference limit value δ d qref(lim) At the same time, in order to ensure that the output current does not exceed the preset maximum current, the maximum value i q qref(lim) of the q-axis component is limited.

[0034] The limiter introduction module is used to introduce the phase angle difference limiter in the power loop for phase angle difference limiting, and introduce the q-axis current limiter in the current loop for q-axis current limiting.

[0035] The output power angle relationship formula of the energy storage inverter under the voltage source type operation control derived in the phase angle difference derivation module is specifically as follows:

[0036]

[0037] wherein, P o is the active power output by the energy storage inverter; V g is the grid voltage; V ref is the output voltage of the energy storage inverter; δ is the difference between the phase angle output by the power loop and the grid-side phase angle obtained by phase locking; X g is the grid line impedance, which is considered to be inductive at this moment.

[0038] The phase angle difference limiting value δ lim is derived according to the maximum output power of the energy storage device, and is specifically as follows:

[0039]

[0040] wherein, δ lim is the phase angle difference limiting value; P max is the maximum power output by the energy storage inverter; V g is the grid voltage; X g is the grid line impedance.

[0041] The current loop d-axis component limiting value i d qref(lim) of the energy storage inverter under the voltage source type operation control in the current limit calculation module is specifically as follows:

[0042]

[0043] wherein, i d qref(lim) is the current loop d-axis component limiting value of the energy storage inverter under the voltage source type operation control; V g is the grid voltage; δ lim is the phase angle difference limiting value; X v is the virtual inductance introduced by the voltage loop.

[0044] The current loop q-axis component limiting value i q qref(lim) of the energy storage inverter under the voltage source type operation control is specifically as follows:

[0045]

[0046] wherein, i q qref(lim) is the current loop q-axis component limiting value of the energy storage inverter under the voltage source type operation control; I max is the maximum current that can be carried and output by the energy storage inverter; i dqref(lim) The d-axis component limit value of the current loop of the voltage source type operation control energy storage inverter.

[0047] Preferably, the phase angle limit calculation formula of the phase angle difference limiter introduced in the limiter introduction module is specifically as follows:

[0048]

[0049] In the formula, the phase angle limit of the phase angle difference limiter is represented by δ, the difference between the phase angle output by the power loop and the grid-side phase angle obtained by phase locking is represented by δ, and the current limit of the current limiter is represented by i. lim The phase angle difference limit value is δ.

[0050] The current limit calculation formula of the q-axis current limiter is specifically as follows:

[0051]

[0052] In the formula, the current limit of the q-axis current limiter is represented by i, the current q-axis component output by the voltage loop is represented by i, and the current q-axis component limit value is represented by i. q qref The current q-axis component output by the voltage loop is represented by i. q qref(lim) The current q-axis component limit value is i.

[0053] In another aspect, the present application further provides an electronic device, which comprises a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the current limiting control method based on the voltage source type operation of the energy storage inverter when executing the computer program.

[0054] In another aspect, the present application further provides a computer readable storage medium, which stores a computer program, and the computer program is executable on a processor to implement the current limiting control method based on the voltage source type operation of the energy storage inverter.

[0055] Compared with the prior art, the present application has the following technical effects:

[0056] ​​The application is aimed at the premise that the output power of the energy storage battery is limited, and the overcurrent scenario of the grid low voltage ride through is considered, and the power loop and the current loop are combined to limit the amplitude, so as to guarantee that the output current under the low voltage fault is within the maximum current bearing. Among them, the power loop detects the maximum power output by the energy storage battery, calculates the limited phase angle difference according to the power angle curve relationship; by limiting the phase angle difference of the energy storage inverter output, the d-axis component of the current loop is limited; at the same time, the current loop considers that the d-axis component has been limited by the phase angle difference, in order to guarantee that the output current is within the maximum current bearing, the q-axis component limiting value is calculated by the maximum current and the d-axis component, and the q-axis component of the current loop is limited. Combined with the reasonable limiting of the power loop and the current loop, the power balance of the front and rear stages is better realized, and the output current of the inverter is not damaged. The switch device can be reasonably guaranteed to run stably, safely and reasonably, the normal operation of the switch device is protected, and the stability of the grid is improved. BRIEF DESCRIPTION OF DRAWINGS

[0057] Figure 1 is the overall flow chart of the current limiting control method based on the voltage source operation of the energy storage inverter described in the application;

[0058] Figure 2 is the power control block diagram of the energy storage inverter described in the application;

[0059] Figure 3 is the output voltage and current waveform diagram of the inverter under the low voltage fault of the grid side in example one;

[0060] Figure 4 is the output voltage and current waveform diagram of the inverter under the low voltage fault of the grid side in example one after using the method described in the application;

[0061] Figure 5 is the control block diagram of the current limiting control system based on the voltage source operation of the energy storage inverter described in the application. DETAILED DESCRIPTION

[0062] In order to make the purpose, technical scheme and advantages of the application more clear, the technical scheme of the application will be described clearly and completely below by combining the specific embodiments of the application and referring to the drawings.

[0063] Example one

[0064] The embodiment provides a current limiting control method based on the voltage source operation of the energy storage inverter, which is used for adapting the energy storage voltage source type inverter based on the droop control and VSG control, as shown in Figure 1 The method comprises the following steps:

[0065] Determine the maximum output power P of the energy storage device through the energy storage unit maxThe output phase angle difference limit value δ is derived based on the power angle curve relationship. lim .

[0066] Based on the phase angle difference limiting value δ of the energy storage inverter output. lim Calculate the maximum value of the d-axis component i of the current-limiting loop. d qref(lim) Meanwhile, to ensure that the output current does not exceed the preset maximum current value, the maximum value of the q-axis component i is... q qref(lim) Restrictions should be imposed.

[0067] A phase angle difference limiter is introduced in the power loop for phase angle difference limiting, and a q-axis current limiter is introduced in the current loop for q-axis current limiting.

[0068] As a preferred embodiment of this example, the formula for the output power angle relationship of the energy storage inverter under voltage source operation control is as follows:

[0069]

[0070] In the formula, P o The energy storage inverter outputs active power; V g V is the mains voltage; ref δ is the output voltage of the energy storage inverter; δ is the difference between the phase angle of the power loop output and the phase angle obtained from the grid side via phase-locked loop; X g Let be the impedance of the power grid line. At this point, we consider that the impedance of the grid-side line is inductive.

[0071] The phase angle difference limit δ is derived based on the maximum output power of the energy storage device. lim Specifically:

[0072]

[0073] In the formula, δ lim P is the phase angle difference limiting value; max This is the maximum output power of the energy storage inverter; V g X is the grid voltage; g This represents the impedance of the power grid line.

[0074] By limiting the phase angle difference of the energy storage inverter output, the d-axis component of the current inner loop is correspondingly limited. As a preferred embodiment of this practice, the d-axis component limiting value i of the energy storage inverter current loop in voltage source type operation control is... d qref(lim) The specific calculation formula is as follows:

[0075]

[0076] In the formula, i d qref(lim)The current loop d-axis component limit value of the voltage source type operation control energy storage inverter g The grid voltage lim The phase angle difference limit value v The virtual inductance introduced by the voltage loop

[0077] To ensure that the output current under low voltage fault is within the maximum current I max The q-axis component needs to be limited, and the current loop q-axis component limit value i q qref(lim) The calculation formula is as follows:

[0078]

[0079] In the formula, i q qref(lim) The current loop q-axis component limit value of the voltage source type operation control energy storage inverter max The maximum current that the energy storage inverter can bear d qref(lim) The current loop d-axis component limit value of the voltage source type operation control energy storage inverter

[0080] As a preferred embodiment of the present embodiment, refer to Figure 2 The power control block diagram of the energy storage inverter is shown, and the phase angle difference limiter is arranged at the position of calculating the output power P o The phase angle limit calculation formula of the phase angle difference limiter is as follows:

[0081]

[0082] In the formula, The phase angle limit of the phase angle difference limiter; the difference between the phase angle output by the power loop and the grid side phase angle obtained by phase locking; the phase angle difference limit value lim The phase angle difference limit value

[0083] The current limit calculation formula of the q-axis current limiter is as follows:

[0084]

[0085] In the formula, The current limit of the q-axis current limiter; i q qref The current q-axis component output by the voltage loop; i q qref(lim) The current loop q-axis component limit value

[0086] In order to verify the effectiveness and superiority of the method provided by the present embodiment, some specific cases are provided as follows:

[0087] To verify the effectiveness and accuracy of the voltage source type network inverter current limiting control method, simulation verification is carried out on the MATLAB / SIMULINK simulation platform. The simulation background is set in the single machine grid based on the droop control of the energy storage network type inverter, wherein the rated active power Pn of the energy storage type network inverter is set to 12kW, and the rated current In of the energy storage type network inverter is set to 25.7A and the rated voltage Un is set to 220V. In order to protect the switching devices in the inverter, the maximum current that the inverter can bear is set to IM=1.2*In=30.8A.

[0088] Case one: without any limiting processing, observe the grid voltage 1.2s occurs 100% voltage drop, 1.3s grid voltage recovery, the output of the inverter during fluctuation, and realize the comparison with the introduction of current limiting control technology.

[0089] Case two: the current limiting control method described in the embodiment is adopted, and the output of the inverter during fluctuation is observed when the grid voltage 1.2s occurs 100% voltage drop and the grid voltage 1.3s recovers, and the comparison with case one is made.

[0090] Figure 3 Figure 4 The simulation results corresponding to the comparison of the two cases respectively prove the accuracy of the voltage source type network inverter current limiting control method described in the embodiment.

[0091] Among them Figure 3 is the output voltage and current waveform diagram of the energy storage inverter when the grid voltage drop occurs without adopting any current limiting measures, that is, when no current limiting measures are adopted, the grid voltage drops at 1.2s, at this time the output current reaches 60A, which is seriously out of limit and exceeds the maximum current that the energy storage device can bear. Figure 4 is the output voltage and current comparison diagram of the energy storage inverter when the grid voltage drop occurs when the current limiting method described in the embodiment is adopted, at this time the current limiting effect is normal, the output current does not fluctuate greatly, and only the characteristic of long buffer time exists.

[0092] Embodiment two

[0093] Correspondingly, the embodiment provides a current limiting control system based on the voltage source operation of the energy storage inverter, which comprises a phase angle difference derivation module, a current limiting calculation module and a limiter introduction module. Referring to Figure 5 , the control strategy of the current limiting control system is to limit the current of the voltage output command value at the output of the voltage loop.

[0094] The phase angle difference derivation module is used to determine the maximum output power P max of the energy storage device through the energy storage unit, and to derive the output phase angle difference limiting value δ according to the power angle curve relationship.​lim .

[0095] a current limit calculation module configured to calculate a maximum value i lim of a d-axis component of a current limit loop according to an amplitude-capped value δ d of a phase angle difference of an output of the energy storage inverter qref(lim) , while limiting a maximum value i q of a q-axis component of the current limit loop to ensure that an output current does not exceed a preset maximum value of the output current. qref(lim)

[0096] an amplitude-capper introduction module configured to introduce an amplitude-capper of the phase angle difference in the power loop to perform amplitude capping of the phase angle difference, and introduce a q-axis current amplitude-capper in the current loop to perform q-axis current amplitude capping.

[0097] As a preferred embodiment of the present embodiment, a formula for deriving an output power angle relationship of the voltage source type operation control in the phase angle difference derivation module is specifically as follows:

[0098]

[0099] In the formula, P o represents an output active power of the energy storage inverter; V g represents a grid voltage; V ref represents an output voltage of the energy storage inverter; δ represents a difference between an output phase angle of the power loop and a grid-side phase angle obtained by phase locking; and X g represents a grid line impedance, which is considered to be inductive at this moment.

[0100] The amplitude-capped value δ lim of the phase angle difference is derived according to a maximum output power of the energy storage device, and is specifically as follows:

[0101]

[0102] In the formula, δ lim represents the amplitude-capped value of the phase angle difference; P max represents a maximum output power of the energy storage inverter; V g represents a grid voltage; and X g represents a grid line impedance.

[0103] As a preferred embodiment of the present embodiment, a formula for calculating the amplitude-capped value i d qref(lim) of the d-axis component of the current loop of the energy storage inverter in the voltage source type operation control in the current limit calculation module is specifically as follows:

[0104]

[0105] In the formula, i d qref(lim) represents the amplitude-capped value of the d-axis component of the current loop of the energy storage inverter in the voltage source type operation control; and Vg is the grid voltage; δ lim is the phase angle difference limit value; X v is the virtual inductance introduced by the voltage loop.

[0106] The current loop q-axis component limit value i of the voltage source type operation control energy storage inverter q qref(lim) The calculation formula is specifically:

[0107]

[0108] In the formula, i q qref(lim) is the current loop q-axis component limit value of the voltage source type operation control energy storage inverter; I max is the maximum current that can be carried by the energy storage inverter; i d qref(lrim) is the current loop d-axis component limit value of the voltage source type operation control energy storage inverter.

[0109] As a preferred embodiment of the present embodiment, the phase angle limit calculation formula of the phase angle difference limiter introduced into the limiter module is specifically:

[0110]

[0111] In the formula, is the phase angle limit of the phase angle difference limiter; δ is the difference between the phase angle output by the power loop and the grid-side phase angle obtained by phase locking; δ lim is the phase angle difference limit value.

[0112] The current limit calculation formula of the q-axis current limiter is specifically:

[0113]

[0114] In the formula, is the current limit of the q-axis current limiter; i q qref is the current q-axis component output by the voltage loop; i q qref(lim) is the current loop q-axis component limit value.

[0115] Embodiment three

[0116] The electronic device includes a memory, a processor, and a computer program stored on the memory and executable on the processor, and the processor implements the current limiting control method based on the voltage source type operation of the energy storage inverter according to any embodiment of the present application when executing the computer program.

[0117] Embodiment four

[0118] The embodiment provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement a current-limiting control method based on energy storage inverter voltage source operation as described in any embodiment of the application.

[0119] In the embodiments of the present application, "at least one" refers to one or more, and "multiple" refers to two or more. The "and / or" describes the association relationship of the associated objects, which means that there can be three kinds of relationships, for example, A and / or B can represent the cases of A alone, A and B together, and B alone. Wherein A and B can be singular or plural. The character " / " generally represents that the front and rear associated objects are in an "or" relationship. "At least one of the following" and the like means any combination of these items, including any combination of single or multiple items. For example, at least one of a, b and c can represent: a, b, c, a and b, a and c, b and c, or a and b and c, wherein a, b, and c can be single or multiple.

[0120] Those skilled in the art can realize that the units and algorithm steps described in the embodiments disclosed in the present application can be realized by electronic hardware, computer software and combination of electronic hardware and computer software. Whether the functions are realized by hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0121] Those skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working process of the system, device and unit described above can refer to the corresponding process in the foregoing method embodiments, which will not be described here.

[0122] In several embodiments provided in the present application, any function realized in the form of a software function unit and sold or used as an independent product can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application essentially or the parts that make contributions to the prior art or parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in the embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (Read-Only Memory, ROM for short), a random access memory (Random Access Memory, RAM for short), a magnetic disk or an optical disk, and various media that can store program codes.

[0123] The above merely illustrates the embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent process transformation, or direct or indirect application in other related technical fields, which are made by using the content of the present application specification and drawings, are also included in the patent protection scope of the present application.

Claims

1. A current limiting control method for voltage source operation of an energy storage inverter, characterized by, The method comprises the following steps: Determine the maximum output power of the energy storage device through the energy storage unit Deduce the output phase angle difference limiting value according to the power angle curve relationship ; Based on the phase angle difference limit value of the energy storage inverter output Calculate the current limiting loop Maximum value of axis component At the same time, ensure that the output current does not exceed the preset maximum current value. Maximum value of axis component To impose restrictions; The phase angle difference limiter is introduced in the power loop to limit the phase angle difference, and the shaft current limiter is introduced in the current loop to limit the shaft current . .

2. The current limiting control method for the energy storage inverter operating as a voltage source, according to claim 1, wherein, The output power angle relationship formula of the voltage source type operation control energy storage inverter is specifically: In the formula, is the active power output by the energy storage inverter; is the grid voltage; is the voltage output by the energy storage inverter; is the difference between the phase angle output by the power loop and the grid-side phase angle obtained by phase locking; is the grid line impedance, which is considered to be inductive at this moment; Deriving a phase angle difference limit value from a maximum output power of an energy storage device Specifically: In the formula, is the phase angle difference limit value; is the maximum power of the energy storage inverter output; is the grid line impedance.

3. The current limiting control method for the energy storage inverter operating as a voltage source, according to claim 1, wherein, Current loop of voltage source type operating control energy storage inverter Shaft component limiting value The calculation formula is specifically: In the formula, Current loop of voltage source type operation control energy storage inverter The shaft component amplitude limit value; The grid voltage; The phase angle difference amplitude limit value; The virtual inductance introduced by the voltage loop; Current loop of voltage source type operating control energy storage inverter Shaft component limiting value The calculation formula is specifically: In the formula, Current loop of voltage source type operation control energy storage inverter The axis component limiting value; The maximum current that the energy storage inverter can bear output; Current loop of voltage source type operation control energy storage inverter The axis component limiting value.

4. The current limiting control method for the energy storage inverter operating as a voltage source, according to claim 1, wherein, The phase angle limiter calculation formula of the phase angle difference limiter is specifically: In the formula, is the phase angle difference limiter; is the difference between the phase angle of the power loop output and the grid-side phase angle obtained by phase locking; is the phase angle difference limiter value; The current limiting calculation formula of the shaft current limiter is specifically: wherein is current limit of the shaft current limiter; is the current limit of the voltage loop output shaft component; is the current loop shaft component limit value.

5. A current limiting control system based on energy storage inverter voltage source operation, characterized by, The phase angle difference derivation module, the current limit calculation module and the limiter introduction module are included. A phase angle difference derivation module is configured to determine the maximum output power of the energy storage device through the energy storage unit , derive the output phase angle difference limiting value according to the power angle curve relationship ; The current limiting calculation module is used to limit the current based on the phase angle difference output of the energy storage inverter. Calculate the limiting current loop Maximum value of axis component Meanwhile, to ensure that the output current does not exceed the preset maximum current value, for Maximum value of axis component To impose restrictions; A limiter introduction module is used to introduce a phase angle difference limiter in the power loop for phase angle difference limiting and a shaft current limiter in the current loop for shaft current limiting shaft current limiting.

6. The current limited control system operating as an energy storage inverter voltage source of claim 5, wherein, The output power angle relationship formula of the voltage source type operation control energy storage inverter is derived in the phase angle difference derivation module and is specifically: In the formula, is the active power output by the energy storage inverter; is the grid voltage; is the voltage output by the energy storage inverter; is the difference between the phase angle output by the power loop and the grid-side phase angle obtained by phase locking; is the grid line impedance, which is considered to be inductive at this moment; Deriving a phase angle difference limit value from a maximum output power of an energy storage device Specifically: In the formula, is the phase angle difference limit value; is the maximum power of the energy storage inverter output; is the grid line impedance.

7. The current limiting control system operating as an energy storage inverter voltage source according to claim 5, wherein, Current limit calculation module for voltage source type operating control of energy storage inverter current loop Shaft component limiting value The calculation formula is specifically: In the formula, Current loop of voltage source type operation control energy storage inverter The shaft component amplitude limit value; The grid voltage; The phase angle difference amplitude limit value; The virtual inductance introduced by the voltage loop; Current loop of voltage source type operating control energy storage inverter Shaft component limiting value The calculation formula is specifically: In the formula, Current loop of voltage source type operation control energy storage inverter The axis component limiting value; The maximum current that the energy storage inverter can bear output; Current loop of voltage source type operation control energy storage inverter The axis component limiting value.

8. The current limited control system operating as an energy storage inverter voltage source of claim 5, wherein, The phase angle limiter calculation formula of the phase angle difference limiter is specifically: In the formula, is the phase angle difference limiter; is the difference between the phase angle of the power loop output and the grid-side phase angle obtained by phase locking; is the phase angle difference limiter value; The current limiting calculation formula of the shaft current limiter is specifically: wherein is current limit of the shaft current limiter; is the current of the voltage loop output shaft component; is the current loop shaft component limit value.

9. An electronic device, comprising: The memory, the processor and the computer program stored in the memory and executable on the processor, characterized in that the processor executes the computer program to realize the current limiting control method based on the voltage source operation of the energy storage inverter according to any one of claims 1 to 4.

10. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to realize the current limiting control method based on the voltage source operation of the energy storage inverter according to any one of claims 1 to 4.

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