Current limiting control method and system based on voltage source operation of energy storage inverter

Abstract

The invention discloses a current limiting control method and system based on voltage source operation of an energy storage inverter, and the method comprises the steps: determining the maximum output power Pmax of energy storage equipment through an energy storage unit, and deducing an output phase angle difference amplitude limiting value delta lim according to a power angle curve relation; according to the phase angle difference amplitude limiting value delta lim output by the energy storage inverter, the d-axis component maximum value idqref (lim) of the limiting current loop is calculated, it is guaranteed that the output current does not exceed the preset current maximum value, and the q-axis component maximum value iqqref (lim) is limited; a phase angle difference amplitude limiter is introduced into a power loop to carry out phase angle difference amplitude limiting, and a q-axis current amplitude limiter is introduced into a current loop to carry out q-axis current amplitude limiting. According to the characteristics of the output power of the input preceding-stage distributed power supply and the overcurrent protection under the grid-side low-voltage ride-through working condition, the stable and safe operation of the energy storage inverter is ensured by setting a limiting control strategy in a power loop and a current loop.

Description

Technical Field

[0001] The present invention belongs to the technical field of power electronics, and in particular relates to a current limiting control method and system based on voltage source operation of an energy storage inverter. Background Art

[0002] Energy storage inverters redistribute power and energy flow in time and space, and can cope with power fluctuations and power supply quality degradation caused by the high penetration of distributed power sources into the grid.

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

[0004] At the same time, energy storage, as a highly flexible, adjustable and controllable equipment in terms of power and energy, can effectively improve the load-bearing and consumption level of distributed photovoltaics and support the construction of new distribution systems. Both energy storage and new energy inverter power generation technologies use power electronic equipment as an important interface, and can simultaneously achieve steady-state control functions such as peak shaving and valley filling and power flow optimization.

[0005] As the degree of power electronics of grid and load equipment increases, the strength of the grid decreases. Common grid-following inverters are prone to instability under weak grid conditions and cannot stably transmit power. Therefore, it is considered to use energy storage inverters that operate in voltage source mode to provide stable voltage and frequency support capabilities for the grid. But at the same time, energy storage inverters that operate in voltage source mode also have certain problems. When the energy storage inverter operates in voltage source mode, it is often regarded as a voltage source series 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 traditional motors. Therefore, for energy storage inverters, its overcurrent technology can be further explored, combined with traditional current loop current limiting control technology, so that the energy storage inverter can adapt to the processing fluctuation characteristics of new energy and meet the needs of building new power systems.

[0006] In the existing voltage source control strategy of energy storage inverter, considering the grid-side fault overcurrent problem of low voltage ride-through of the power grid, in order to protect the energy storage inverter, the current loop limiting control strategy and the removal strategy are often adopted. When the inverter output current exceeds the current that the switching device can carry, the traditional control strategy often considers the current loop limiting, that is, limiting the d-axis and q-axis components of the current loop. 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 operation cannot be restored normally after the grid-side fault ends.

[0007] The Chinese patent with publication number CN117458599A also discloses a current limiting control method for voltage source operation of an energy storage inverter, comprising 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 to limit the d-axis and q-axis current command values ​​in the dq coordinate system respectively; introducing a phase-locked loop PLL link 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 into the phase angle switching link, when the current limiter is not triggered, the frequency and phase angle of the energy storage inverter output are maintained, 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 the current limiter is triggered, it is determined whether the output frequency of the energy storage inverter is restored to within the threshold, and if it is restored, 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 this invention sets the limiting amplitude based on the rated current and maximum load-bearing current of the inverter, adopts static limiting measures, and mainly relies on a pre-set maximum current limit. It cannot respond quickly to changes in complex power grids or dynamic load changes, and cannot flexibly cope with current fluctuations under different load conditions. Summary of the invention

[0008] In order to solve the adverse effects of the output fluctuation of renewable energy and low voltage fault on the grid side in the above-mentioned prior art on the energy storage inverter, the present invention provides a current limiting control method and system based on the voltage source operation of the energy storage inverter. According to the output power characteristics of the input front-stage distributed power supply and considering the overcurrent protection under the low voltage ride-through condition on the grid side, a limiting control strategy is set in the power loop and the current loop to ensure the stable and safe operation of the energy storage inverter.

[0009] In order to solve the above technical problems, the present invention provides a current limiting control method based on voltage source operation of an energy storage inverter, comprising the following steps:

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

[0011] According to the phase difference limit value δ output by the energy storage inverter lim , calculate the maximum value i of the d-axis component of the limiting current loop d qref(lim) , while ensuring that the output current does not exceed the preset maximum current value, the maximum value of the q-axis component i q qref(lim) Make restrictions.

[0012] A phase angle difference limiter is introduced into the power loop to limit the phase angle difference, and a 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 energy storage inverter controlled by voltage source operation is specifically:

[0014]

[0015] Where P o Output active power for 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. At this moment, the grid side line impedance is considered to be inductive.

[0016] Derivation of the phase angle difference limit value δ based on the maximum output power of the energy storage device lim Specifically:

[0017]

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

[0019] Preferably, the voltage source type operation control energy storage inverter current loop d-axis component limit value i d qref(kim) The specific calculation formula is:

[0020]

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

[0022] The q-axis component limit value i of the current loop of the energy storage inverter under voltage source operation control q qref(lim) The specific calculation formula is:

[0023]

[0024] In the formula, i q qref(lim)I is the q-axis component limit value of the current loop of the energy storage inverter controlled by voltage source operation; max is the maximum current that the energy storage inverter can carry; i d qref(lim) It is the limit value of the d-axis component of the current loop of the energy storage inverter controlled by voltage source operation.

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

[0026]

[0027] In the formula, is the phase angle limiter 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.

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

[0029]

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

[0031] On the other hand, the present invention provides a current limiting control system based on the voltage source operation of an energy storage inverter, including a phase angle difference derivation module, a current limiting calculation module and a limiter introduction module.

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

[0033] The current limit calculation module is used to calculate the phase difference limit value δ output by the energy storage inverter. lim , calculate the maximum value i of the d-axis component of the limiting current loop 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 of the q-axis component i q qref(lim) Make restrictions.

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

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

[0036]

[0037] Where P o Output active power for 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. At this moment, the grid side line impedance is considered to be inductive.

[0038] Derivation of the phase angle difference limit value δ based on the maximum output power of the energy storage device lim Specifically:

[0039]

[0040] In the formula, δ lim is the phase angle difference limit value; P max The maximum power output of the energy storage inverter; V g is the grid voltage; X g is the grid line impedance.

[0041] Preferably, the current loop d-axis component limit value i of the energy storage inverter controlled by the voltage source type operation in the current limit calculation module d qref(lim) The specific calculation formula is:

[0042]

[0043] In the formula, i d qref(lim) is the d-axis component limit value of the current loop of the energy storage inverter controlled by voltage source operation; V g is the grid voltage; δ lim is the phase angle difference limit value; X v Virtual inductance introduced for the voltage loop.

[0044] The q-axis component limit value i of the current loop of the energy storage inverter under voltage source operation control q qref(lim) The specific calculation formula is:

[0045]

[0046] In the formula, i q qref(lim) I is the q-axis component limit value of the current loop of the energy storage inverter controlled by voltage source operation; max is the maximum current that the energy storage inverter can carry; i dqref(lim) It is the limit value of the d-axis component of the current loop of the energy storage inverter controlled by voltage source operation.

[0047] Preferably, the phase angle limiting calculation formula of the phase angle difference limiter in the limiter introduction module is specifically:

[0048]

[0049] In the formula, is the phase angle limiter 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.

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

[0051]

[0052] In the formula, is the current limit of the q-axis current limiter; i q qref is the current q-axis component of the voltage loop output; i q qref(lim) is the amplitude limit of the q-axis component of the current loop.

[0053] On the other hand, the present invention also provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the current limiting control method based on the voltage source operation of the energy storage inverter as described in any embodiment of the present invention is implemented.

[0054] On the other hand, the present invention further provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the current limiting control method based on voltage source operation of an energy storage inverter as described in any embodiment of the present invention is implemented.

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

[0056] The present invention aims at the premise that the output power of the energy storage battery is limited, and takes into account the overcurrent scenario of low voltage crossing of the power grid, and jointly limits the power loop and the current loop to ensure that the output current under low voltage fault is within the maximum current value carried. Among them, the power loop detects the maximum power output of the energy storage battery, and calculates the limited phase angle difference according to the power angle curve relationship; by limiting the phase angle difference output by the energy storage inverter, the d-axis component of the current loop is correspondingly 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 ensure that the output current is within the maximum current value carried, the q-axis component limit value is calculated by the current maximum value and the d-axis component, and the q-axis component of the current loop is correspondingly 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 achieved and the output current of the inverter is guaranteed not to damage the switching device, which can reasonably ensure the stable, safe and reasonable operation of the energy storage inverter, protect the normal operation of the switching device, and improve the stability of the power grid. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0058] Figure 2 It is a power control block diagram of the energy storage inverter described in the present invention;

[0059] Figure 3 It is the waveform diagram of the unlimited output voltage and current of the inverter with grid-side low voltage fault described in the first embodiment;

[0060] Figure 4 This is a waveform diagram of the output voltage and current of the inverter with low voltage fault on the grid side after the method of the present invention is adopted in the first embodiment;

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

[0062] In order to make the objectives, technical solutions and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in combination with specific embodiments of the present application and with reference to the accompanying drawings.

[0063] Embodiment 1

[0064] This embodiment provides a current limiting control method based on voltage source operation of an energy storage inverter, which is used to adapt to an energy storage voltage source inverter based on droop control and VSG control. Figure 1 As shown, the following steps are included:

[0065] Determine the maximum output power P of the energy storage device through the energy storage unit max, according to the power angle curve relationship, the output phase angle difference limit value δ is derived lim .

[0066] According to the phase difference limit value δ output by the energy storage inverter lim , calculate the maximum value i of the d-axis component of the limiting current loop 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 of the q-axis component i q qref(lim) Make restrictions.

[0067] A phase angle difference limiter is introduced into the power loop to limit the phase angle difference, and a q-axis current limiter is introduced into the current loop to limit the q-axis current.

[0068] As a preferred implementation of this embodiment, the output power angle relationship formula of the energy storage inverter controlled by voltage source operation is specifically:

[0069]

[0070] Where P o Output active power for 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. At this moment, the grid side line impedance is considered to be inductive.

[0071] Derivation of the phase angle difference limit value δ based on the maximum output power of the energy storage device lim Specifically:

[0072]

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

[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 implementation of this embodiment, the d-axis component limit value i of the current loop of the energy storage inverter controlled by voltage source operation is d qref(lim) The specific calculation formula is:

[0075]

[0076] In the formula, i d qref(lim)is the d-axis component limit value of the current loop of the energy storage inverter controlled by voltage source operation; V g is the grid voltage; δ lim is the phase angle difference limit value; X v Virtual inductance introduced for 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 of the energy storage inverter current loop q-axis component limit value i q qref(lim) The specific calculation formula is:

[0078]

[0079] In the formula, i q qref(lim) I is the q-axis component limit value of the current loop of the energy storage inverter controlled by voltage source operation; max is the maximum current that the energy storage inverter can carry; i d qref(lim) It is the limit value of the d-axis component of the current loop of the energy storage inverter controlled by voltage source operation.

[0080] As a preferred implementation of this embodiment, refer to Figure 2 As shown in the figure, it is the power control block diagram of the energy storage inverter, and its phase difference limiter is set to calculate 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, is the phase angle limiter 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.

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

[0084]

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

[0086] In order to verify the effectiveness and superiority of the method provided in this embodiment, some specific cases are provided below:

[0087] In order to verify the effectiveness and accuracy of the current limiting control method of the voltage source grid-connected inverter, simulation verification was carried out on the MATLAB / SIMULINK simulation platform. The simulation background is set in the single-machine grid-connected energy storage grid-connected inverter based on droop control, in which the rated active power Pn of the energy storage grid-connected inverter is set to 12kW, the rated current In of the energy storage grid-connected 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] Working condition 1: Without any restriction, the grid voltage drops by 100% at 1.2s and returns to normal at 1.3s. The output of the inverter during the fluctuation is compared with that achieved by introducing current limiting control technology.

[0089] Working condition 2: using the current limiting control method described in this embodiment, observe that the grid voltage drops by 100% at 1.2s and the grid voltage returns to normal at 1.3s. The output of the inverter during the fluctuation is compared with working condition 1.

[0090] Figure 3 , Figure 4 The simulation results correspond to the comparison of the two working conditions, which proves the accuracy of the current limiting control method of the voltage source grid-connected inverter described in this embodiment.

[0091] in Figure 3 The output voltage and current waveforms are when the grid voltage drops and the energy storage inverter does not adopt 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 over the limit and exceeds the maximum current that the energy storage device can carry. Figure 4 The output voltage and current comparison diagram is when the grid voltage drops when the energy storage inverter adopts the current limiting method described in this embodiment. At this time, the current limiting effect is normal, the output current will not fluctuate greatly, and there is only a long buffer time.

[0092] Embodiment 2

[0093] Accordingly, this embodiment provides a current limiting control system based on voltage source operation of an energy storage inverter, including a phase angle difference derivation module, a current limiting calculation module and a limiter introduction module. Figure 5 As shown, the control strategy of the current limiting control system is to perform current limiting on the command value of the voltage output at the output of the voltage loop.

[0094] Phase angle difference derivation module, used to determine the maximum output power P of the energy storage device through the energy storage unit max , according to the power angle curve relationship, the output phase angle difference limit value δ is derivedlim .

[0095] The current limit calculation module is used to calculate the phase difference limit value δ output by the energy storage inverter. lim , calculate the maximum value i of the d-axis component of the limiting current loop 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 of the q-axis component i q qref(lim) Make restrictions.

[0096] The limiter introduction module is used to introduce a phase difference limiter in the power loop to perform phase difference limiting, and to introduce a q-axis current limiter in the current loop to perform q-axis current limiting.

[0097] As a preferred implementation of this embodiment, the phase angle difference derivation module derives the output power angle relationship formula of the energy storage inverter under voltage source type operation control as follows:

[0098]

[0099] Where P o Output active power for 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. At this moment, the grid side line impedance is considered to be inductive.

[0100] Derivation of the phase angle difference limit value δ based on the maximum output power of the energy storage device lim Specifically:

[0101]

[0102] In the formula, δ lim is the phase angle difference limit value; P max The maximum power output of the energy storage inverter; V g is the grid voltage; X g is the grid line impedance.

[0103] As a preferred implementation of this embodiment, the current loop d-axis component limit value i of the energy storage inverter current loop of the voltage source type operation control in the current limit calculation module d qref(lim) The specific calculation formula is:

[0104]

[0105] In the formula, i d qref(lim) is the d-axis component limit value of the current loop of the energy storage inverter controlled by voltage source operation; Vg is the grid voltage; δ lim is the phase angle difference limit value; X v Virtual inductance introduced for the voltage loop.

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

[0107]

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

[0109] As a preferred implementation of this embodiment, the phase angle limiting calculation formula of the phase angle difference limiter in the limiter introduction module is specifically:

[0110]

[0111] In the formula, is the phase angle limiter 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 as follows:

[0113]

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

[0115] Embodiment 3

[0116] This embodiment provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the current limiting control method based on the voltage source operation of the energy storage inverter as described in any embodiment of the present invention is implemented.

[0117] Embodiment 4

[0118] This embodiment provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the current limiting control method based on voltage source operation of an energy storage inverter as described in any embodiment of the present invention is implemented.

[0119] In the embodiments of the present application, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, c can be single or multiple.

[0120] Those of ordinary skill in the art will appreciate that the various units and algorithm steps described in the embodiments disclosed herein can be implemented in a combination of electronic hardware, computer software, and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0121] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0122] In several embodiments provided in the present application, if any function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory; hereinafter referred to as: ROM), random access memory (Random Access Memory; hereinafter referred to as: RAM), disk or optical disk, and other media that can store program codes.

[0123] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A current limiting control method based on voltage source operation of an energy storage inverter, characterized in that: The following steps are involved: Determine the maximum output power P of the energy storage device through the energy storage unit max , according to the power angle curve relationship, the output phase angle difference limit value δ is derived lim ; According to the phase difference limit value δ output by the energy storage inverter lim , calculate the maximum value i of the d-axis component of the limiting current loop d qref(lim) , while ensuring that the output current does not exceed the preset maximum current value, the maximum value of the q-axis component i q qref(lim) impose restrictions; A phase angle difference limiter is introduced into the power loop to limit the phase angle difference, and a q-axis current limiter is introduced into the current loop to limit the q-axis current.

2. The current limiting control method based on voltage source operation of energy storage inverter according to claim 1 is characterized in that: The specific formula for the output power angle relationship of the energy storage inverter controlled by voltage source operation is: Where P o Output active power for 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. At this moment, the grid-side line impedance is considered to be inductive; Derivation of the phase angle difference limit value δ based on the maximum output power of the energy storage device lim Specifically: In the formula, δ lim is the phase angle difference limit value; P max The maximum power output of the energy storage inverter; V g is the grid voltage; X g is the grid line impedance.

3. The current limiting control method based on voltage source operation of energy storage inverter according to claim 1 is characterized in that: The d-axis component limit value i of the current loop of the energy storage inverter under voltage source operation control d qref(lim) The specific calculation formula is: In the formula, i d qref(lim) is the d-axis component limit value of the current loop of the energy storage inverter controlled by voltage source operation; V g is the grid voltage; δ lim is the phase angle difference limit value; X v Virtual inductance introduced for the voltage loop; The q-axis component limit value i of the current loop of the energy storage inverter under voltage source operation control q qref(lim) The specific calculation formula is: In the formula, i q qref(lim) I is the q-axis component limit value of the current loop of the energy storage inverter controlled by voltage source operation; max is the maximum current that the energy storage inverter can carry; i d qref(lim) It is the limit value of the d-axis component of the current loop of the energy storage inverter controlled by voltage source operation.

4. The current limiting control method based on voltage source operation of energy storage inverter according to claim 1 is characterized in that: The phase angle limiting calculation formula of the phase angle difference limiter is as follows: In the formula, is the phase angle limiter 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; The current limit calculation formula of the q-axis current limiter is as follows: In the formula, is the current limit of the q-axis current limiter; i q qref is the current q-axis component of the voltage loop output; i q qref(lim) is the amplitude limit of the q-axis component of the current loop.

5. A current limiting control system based on voltage source operation of energy storage inverter, characterized in that: It includes a phase angle difference derivation module, a current limit calculation module and a limiter introduction module; Phase angle difference derivation module, used to determine the maximum output power P of the energy storage device through the energy storage unit max , according to the power angle curve relationship, the output phase angle difference limit value δ is derived lim ; The current limit calculation module is used to calculate the phase difference limit value δ output by the energy storage inverter. lim , calculate the maximum value i of the d-axis component of the limiting current loop 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 of the q-axis component i q qref(lim) impose restrictions; The limiter introduction module is used to introduce a phase difference limiter in the power loop to perform phase difference limiting, and to introduce a q-axis current limiter in the current loop to perform q-axis current limiting.

6. The current limiting control system based on voltage source operation of energy storage inverter according to claim 5 is characterized in that: The output power angle relationship formula of the energy storage inverter for voltage source type operation control in the phase angle difference derivation module is as follows: Where P o Output active power for 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. At this moment, the grid-side line impedance is considered to be inductive; Derivation of the phase angle difference limit value δ based on the maximum output power of the energy storage device lim Specifically: In the formula, δ lim is the phase angle difference limit value; P max The maximum power output of the energy storage inverter; V g is the grid voltage; X g is the grid line impedance.

7. The current limiting control system based on voltage source operation of energy storage inverter according to claim 5 is characterized in that: The current loop d-axis component limit value i of the energy storage inverter in the voltage source type operation control in the current limit calculation module d qref(lim) The specific calculation formula is: In the formula, i d qref(lim) is the d-axis component limit value of the current loop of the energy storage inverter controlled by voltage source operation; V g is the grid voltage; δ lim is the phase angle difference limit value; X v Virtual inductance introduced for the voltage loop; The q-axis component limit value i of the current loop of the energy storage inverter under voltage source operation control q qref(lim) The specific calculation formula is: In the formula, i q qref(lim) I is the q-axis component limit value of the current loop of the energy storage inverter controlled by voltage source operation; max is the maximum current that the energy storage inverter can carry; i d qref(lim) It is the limit value of the d-axis component of the current loop of the energy storage inverter controlled by voltage source operation.

8. The current limiting control system based on voltage source operation of energy storage inverter according to claim 5 is characterized in that: The phase angle limiting calculation formula of the phase angle difference limiter in the limiter introduction module is as follows: In the formula, is the phase angle limiter 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; The current limit calculation formula of the q-axis current limiter is as follows: In the formula, is the current limit of the q-axis current limiter; i q qref is the current q-axis component of the voltage loop output; i q qref(lim) is the amplitude limit of the q-axis component of the current loop.

9. An electronic device, comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the current limiting control method based on the voltage source operation of the energy storage inverter as described in any one of claims 1 to 4 is implemented.

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

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