A method for cooperative control of a grid-connected interface switch and a grid-connected interface switch

Abstract

The embodiment of the application discloses a kind of coordinated control methods and grid-connected demarcation switch of grid-connected demarcation switch, method includes obtaining the operating data of grid-connected point where grid-connected demarcation switch is;The operating state of power grid is monitored based on operating data, wherein, monitoring item at least includes island detection, power quality evaluation and anti-sending electric power monitoring;If the operating state of power grid is monitored to exist exception, then according to abnormal state level grading is intervened and is regulated.This embodiment of the application utilizes the operating data of grid-connected point to monitor the operating state of power grid, and according to the abnormal state level of monitoring grading is intervened and is handled, solve the protection function single of prior art in middle-low voltage network source demarcation switch, response mechanism passive and not having the technical problem of coordinated control capability, realize the real-time monitoring of new energy grid-connected point operating state using grid-connected demarcation switch, intelligent analysis and active adjustment technical effect.

Description

Technical Field

[0001] This invention relates to the field of power grid automation technology, and in particular to a collaborative control method for a grid-connected boundary switch and the grid-connected boundary switch itself. Background Technology

[0002] In the context of new power system construction, traditional medium- and low-voltage grid-source separation switchgear faces significant technical bottlenecks. These devices were initially designed primarily to adapt to traditional distribution network structures with unidirectional power flow, focusing on fault interruption and protection, and lacking adaptability to the characteristics of new energy grid integration. With the large-scale integration of distributed photovoltaic, wind power, and other new energy sources, the distribution network exhibits significant morphological evolution characteristics: power flow direction changes from unidirectional to bidirectional, voltage fluctuation amplitude increases, harmonic content increases significantly, and system frequency stability faces challenges.

[0003] At the same time, traditional sectionalizing switches have shown significant shortcomings in dealing with these new problems: their protection functions are limited, with only basic overcurrent and overvoltage protection, lacking power quality monitoring capabilities, unable to identify anomalies such as harmonic distortion and voltage fluctuations, and their response mechanisms are passive, only acting after a fault occurs, and lacking the ability to coordinate control with new energy equipment. Summary of the Invention

[0004] This invention provides a collaborative control method for grid-connected sectionalizing switches and a grid-connected sectionalizing switch, which solves the technical problems of existing medium and low voltage grid-source sectionalizing switches having single protection functions, passive response mechanisms, and no collaborative control capabilities.

[0005] This invention provides a coordinated control method for grid-connected boundary switches, the method comprising:

[0006] Obtain the operating data of the grid connection point where the grid connection boundary switch is located, wherein the operating data includes at least the voltage, current, frequency, power, and harmonic distortion rate of the grid connection point;

[0007] The power grid's operating status is monitored based on the aforementioned operating data, and the monitoring items include at least islanding detection, power quality assessment, and backfeed power monitoring.

[0008] If an abnormality is detected in the operation of the power grid, intervention and control will be carried out according to the level of the abnormality.

[0009] Furthermore, while monitoring the operating status of the power grid based on the aforementioned operating data, the method also includes:

[0010] The timing of data reporting is determined based on the operating data and the preset dead zone threshold, wherein the preset dead zone threshold includes at least the current change dead zone threshold, the AC voltage change dead zone threshold, the DC voltage change dead zone threshold, and the power change dead zone threshold.

[0011] Furthermore, monitoring the operating status of the power grid based on the aforementioned operating data includes:

[0012] Based on the operational data, islanding detection of the power grid is performed using the active frequency offset method or the voltage phase jump detection method.

[0013] Based on the operational data, the power grid is assessed for power quality using a preset power quality threshold.

[0014] Based on the operational data, the reverse power transmission power of the power grid is monitored using a preset reverse power threshold.

[0015] Furthermore, if an abnormality is detected in the operating status of the power grid, intervention and control measures will be implemented according to the level of the abnormality, including:

[0016] If an abnormality is detected in the operation of the power grid and the abnormality level is Level 1, an audible and visual alarm will be issued and the abnormality information will be recorded. The Level 1 abnormality level is when the range of the threshold is less than the first set range or there is a situation that does not need to be processed within the first time period.

[0017] If an abnormality is detected in the operation of the power grid and the abnormality level is level two, an adjustment command is sent to the new energy inverter through the local communication interface to perform remote power adjustment. The level two abnormality level is when an abnormality in power quality is detected or the operating parameters deviate from the threshold by a range greater than the first set range and less than the second set range.

[0018] If an abnormality is detected in the operation of the power grid and the abnormality level is three, local reactive power compensation is performed using preset parallel reactors or capacitor banks to stabilize the grid connection point voltage. The level three abnormality level is a situation where communication with the inverter is impossible or remote adjustment is ineffective.

[0019] If an abnormality is detected in the operation of the power grid and the abnormality level is four, a trip isolation operation will be performed. The level four abnormality level is a short circuit fault or a situation where the regulation measures of level one to three are ineffective.

[0020] Furthermore, islanding detection of the power grid using the active frequency offset method or voltage phase transition detection method includes:

[0021] Islanding detection of the power grid is performed by using the active frequency offset method or the voltage phase jump detection method, combined with the voltage frequency change setting and the islanding protection delay setting.

[0022] Furthermore, the power quality assessment reference includes at least one of the following: harmonic distortion rate, voltage deviation, and three-phase imbalance.

[0023] Furthermore, after monitoring the reverse power transmission to the power grid using a preset reverse power threshold, the method further includes:

[0024] If the power transmitted back to the grid by new energy generation exceeds the preset reverse power threshold, and the range of exceeding the threshold is less than the first set range, an alarm will be issued and abnormal status information will be recorded.

[0025] If the power transmitted back to the grid by the new energy power generation exceeds the preset reverse power threshold, and the power continues to exceed the threshold for a period of time that reaches a first preset duration, then a stepped power reduction control or trip protection will be implemented.

[0026] This invention also provides a grid-connected boundary switch, the switch comprising a main switch unit and a measurement and control unit;

[0027] The main switch unit and the measurement and control unit are electrically connected;

[0028] The measurement and control unit is used to acquire the operation data of the grid connection point, monitor the operation status of the power grid based on the operation data, and if an abnormality is detected in the operation status of the power grid, intervention and control are carried out according to the level of abnormality. The operation data includes at least the voltage, current, frequency, power and harmonic distortion rate of the grid connection point, and the monitoring items include at least islanding detection, power quality assessment and backfeed power monitoring.

[0029] The main switch unit is used to perform opening and closing operations under the control of the measurement and control unit, and to regulate corresponding abnormal states.

[0030] Furthermore, the measurement and control unit includes a communication management module;

[0031] The communication management module includes a local communication interface and a remote communication submodule.

[0032] Furthermore, the measurement and control unit also includes a power supply module;

[0033] The power module includes an automatic battery activation submodule and a power fault detection submodule.

[0034] This invention discloses a collaborative control method for grid-connected boundary switches and a grid-connected boundary switch. The method includes acquiring operational data of the grid connection point where the boundary switch is located; monitoring the grid's operational status based on the operational data, wherein the monitoring items include at least islanding detection, power quality assessment, and backfeed power monitoring; if an abnormality is detected in the grid's operational status, intervention and regulation are carried out according to the level of the abnormality. This invention utilizes operational data from the grid connection point to monitor the grid's operational status and performs graded intervention based on the detected abnormality level, solving the technical problems of existing medium- and low-voltage grid-source boundary switches having single protection functions, passive response mechanisms, and lack of collaborative control capabilities. It achieves the technical effect of real-time monitoring, intelligent analysis, and proactive adjustment of the operational status of new energy grid connection points using the grid-connected boundary switch. Attached Figure Description

[0035] Figure 1 This is a flowchart of a pin status configuration method provided in an embodiment of the present invention. Detailed Implementation

[0036] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0037] It should be noted that the terms "first," "second," etc., in the specification, claims, and drawings of this invention are used to distinguish different objects, not to limit a specific order. The various embodiments of this invention described below can be performed individually or in combination with each other; the embodiments of this invention do not impose specific limitations in this regard.

[0038] Figure 1 This is a flowchart of a collaborative control method for a grid-connected boundary switch provided in an embodiment of the present invention.

[0039] like Figure 1 As shown, the coordinated control method for the grid-connected boundary switch specifically includes the following steps:

[0040] S101, acquire the operating data of the grid connection point where the grid connection boundary switch is located, wherein the operating data includes at least the voltage, current, frequency, power and harmonic distortion rate of the grid connection point.

[0041] Specifically, the grid-connected boundary switch is equipped with high-precision sensors and current transformers to continuously collect operational data such as voltage (U), current (I), frequency (f), power (P, Q), and total harmonic distortion (THD) at the grid connection point where the switch is located. Simultaneously, the acquired operational data undergoes feature extraction, including voltage and current amplitude changes, frequency fluctuation trends, harmonic content distribution, and power flow direction and magnitude changes, providing data support for subsequent operational status assessment.

[0042] S102, monitor the operating status of the power grid based on operational data, including at least islanding detection, power quality assessment and backfeed power monitoring.

[0043] Specifically, while acquiring operational data, the system monitors the grid's operational status in real time based on various pre-set monitoring algorithms and thresholds to achieve comprehensive control over new energy grid connection points, promptly detect anomalies, and proactively intervene in regulation, thereby enabling early intervention in the grid's operational status and reducing the probability of faults.

[0044] S103 If an abnormality is detected in the operation of the power grid, intervention and control shall be carried out according to the level of abnormality.

[0045] Specifically, if an abnormality is detected in the operation of the power grid, different interventions will be carried out according to the severity of the abnormality, so as to maximize the grid connection time of new energy power generation, reduce unnecessary grid disconnection, and improve the utilization rate of new energy while ensuring the safety of the power grid.

[0046] In this embodiment of the invention, the grid-connected boundary switch can also achieve real-time data upload and remote interaction. Specifically, the measurement and control unit within the switch uploads all operation records, waveform data, power quality reports, fault information, etc., to the main station or cloud platform in real time. It also supports remote setting modification and strategy optimization. Maintenance personnel can remotely adjust protection settings and control strategy parameters, such as overcurrent protection settings, voltage and frequency protection settings, and low-voltage ride-through related parameters, through the main station. Furthermore, the terminal has a fault remote signaling hold function. After a fault remote signaling is set, it is held for a set time (configurable via parameters) before resuming, ensuring that the main station can accurately receive and record fault information.

[0047] This invention utilizes the operational data of grid connection points to monitor the operating status of the power grid and performs graded intervention based on the level of abnormal status detected. This solves the technical problems of existing medium and low voltage grid-source merging switches having a single protection function, a passive response mechanism, and no collaborative control capability. It achieves the technical effect of real-time monitoring, intelligent analysis, and proactive adjustment of the operating status of new energy grid connection points using grid connection merging switches.

[0048] Based on the above technical solutions, in step S102, while monitoring the operating status of the power grid based on operational data, the method also includes:

[0049] The timing of data reporting is determined based on operational data and preset dead-zone thresholds. The preset dead-zone thresholds include at least current change dead-zone thresholds, AC voltage change dead-zone thresholds, DC voltage change dead-zone thresholds, and power change dead-zone thresholds.

[0050] Specifically, during the data acquisition process, the current operating status of the power grid can be monitored intuitively based on pre-set parameters such as current change dead zone threshold, AC voltage change dead zone threshold, DC voltage change dead zone threshold, and power change dead zone threshold. When the change in relevant electrical quantities exceeds the set dead zone threshold, the measurement and control unit of the grid-connected boundary switch actively sends up the changed data to ensure the real-time performance and effectiveness of data acquisition.

[0051] Based on the above technical solutions, S102 specifically includes:

[0052] Based on operational data, islanding detection of the power grid is performed using the active frequency offset method or voltage phase jump detection method; based on operational data, power quality assessment of the power grid is performed using preset power quality thresholds; based on operational data, back-feeding power monitoring of the power grid is performed using preset reverse power thresholds.

[0053] Optionally, islanding detection of the power grid using the active frequency offset method or voltage phase jump detection method includes: using the active frequency offset method or voltage phase jump detection method, combined with voltage frequency change setting and islanding protection delay setting, to perform islanding detection of the power grid.

[0054] Specifically, islanding detection integrates Active Frequency Drift (AFD) or voltage phase jump detection methods, while also incorporating voltage frequency change setpoints (default 1.5Hz) and islanding protection delays (default 0.2S) to improve the speed and accuracy of islanding detection and effectively avoid the failure zones of traditional single detection methods. When islanding is detected, relevant protection actions are quickly triggered to ensure the safety of power grid equipment and personnel.

[0055] Optionally, power quality assessment references may include at least one of the following: harmonic distortion rate, voltage deviation, and three-phase imbalance.

[0056] Specifically, the preset power quality thresholds are set based on national standards and empirical thresholds to evaluate the collected power quality data in real time. When any of the power quality assessment references, such as harmonic distortion rate, voltage deviation, or three-phase imbalance, exceeds the set threshold, an early warning or protection action is triggered.

[0057] The default alarm thresholds for power quality exceeding limits are ±4%, voltage imbalance exceeding limits are 4%Un, current imbalance exceeding limits are 4%In, voltage deviation exceeding limits are ±7%Un, and DC component exceeding limits are 0.5%In. The default confirmation time is 60 seconds. All thresholds can be flexibly adjusted according to actual operating requirements.

[0058] Optionally, after monitoring the reverse power transmission to the power grid using a preset reverse power threshold, the method further includes: if the reverse power transmission from new energy generation to the power grid exceeds the preset reverse power threshold, and the range of exceeding the threshold is less than a first set range, then an alarm is triggered and abnormal status information is recorded.

[0059] If the power transmitted back to the grid by new energy generation exceeds the preset reverse power threshold, and the power continues to exceed the threshold for a period of time that reaches the first preset duration, then step-by-step power reduction control or trip protection will be implemented.

[0060] Specifically, a preset reverse power threshold can be set to 0.05Ir, where Ir is the rated current of distributed power generation. When the power fed back to the grid by new energy generation exceeds this threshold, the measurement and control unit of the grid-connected boundary switch will first issue an alarm and record the relevant events. If the power continues to exceed the limit and endangers the safe operation of the grid, a stepped power reduction control or trip protection can be implemented to avoid direct tripping and waste of new energy generation resources.

[0061] Based on the above technical solutions, S103 specifically includes:

[0062] If an abnormality is detected in the operation of the power grid and the abnormality level is Level 1, an audible and visual alarm will be triggered and the abnormality information will be recorded. The Level 1 abnormality level is when the range of the threshold is less than the first set range or there is a situation that does not need to be handled within the first time period.

[0063] If an abnormality is detected in the operation of the power grid and the abnormality level is level two, an adjustment command is sent to the new energy inverter through the local communication interface to perform remote power adjustment. The level two abnormality level is when an abnormality in power quality is detected or the operating parameters deviate from the threshold by a range greater than the first set range and less than the second set range.

[0064] If an abnormality is detected in the operation of the power grid and the abnormality level is three, local reactive power compensation will be performed using the preset parallel reactors or capacitor banks to stabilize the voltage at the grid connection point. The abnormality level three is a situation where communication with the inverter is impossible or remote adjustment is ineffective.

[0065] If an abnormality is detected in the power grid's operating status, and the abnormality level is four, a trip isolation operation will be performed. The level four abnormality level is a short-circuit fault or a situation where the regulation measures of level one to three are ineffective.

[0066] Specifically, this invention creatively proposes a four-level flexible control strategy of "alarm-remote adjustment-local compensation-final tripping". When the first level of abnormal status occurs, an alarm and recording strategy is primarily adopted. Specifically, for minor exceedances (i.e., the range exceeding the threshold is less than the first set range) or non-emergency abnormalities (i.e., situations that do not require processing within the first time period), the grid-connected boundary switch's measurement and control unit issues an audible and visual alarm signal, while simultaneously recording detailed information such as the event occurrence time, abnormal parameter values, and waveform data, providing a basis for subsequent analysis and troubleshooting.

[0067] When a Level 2 abnormal state occurs, a proactive adjustment strategy is mainly adopted. That is, when an abnormal power quality or deviation of operating parameters from the ideal range is detected, adjustment commands are sent to the renewable energy inverter through the local communication interface. Reactive power regulation (QV control) is used to stabilize the grid connection point voltage, and active power load easing (Pf control) is used to stabilize the system frequency, thereby achieving proactive intervention in the grid operation status and preventing the abnormality from escalating.

[0068] When a Level 3 abnormal state occurs, a local flexible control strategy is primarily adopted. This means that in cases where communication with the inverter is impossible or remote adjustment is ineffective, the switch itself can connect / disconnect pre-configured parallel reactors or capacitor banks for local reactive power compensation, quickly stabilizing the grid connection point voltage. Simultaneously, combined with the low-voltage ride-through function, when the distributed power source has low-voltage ride-through capability, this function is enabled and undervoltage protection is disabled; when the distributed power source does not have low-voltage ride-through capability, the low-voltage ride-through function is disabled and undervoltage protection is enabled. The low-voltage ride-through amplitude and time meet the requirements of Q / GDW 12072—2020, ensuring stable system operation during abnormal voltage drops.

[0069] When a Level 4 abnormal condition occurs, the traditional protection strategy is mainly adopted. That is, when a serious fault such as a short circuit occurs, or when the adjustment measures of the above levels are ineffective and the operating condition continues to deteriorate, endangering the safety of the power grid, the measurement and control unit of the grid-connected boundary switch performs a fast trip isolation operation. Overcurrent protection, zero-sequence overcurrent protection, voltage and frequency over-limit protection, etc., strictly follow the preset action settings and time limits to ensure rapid fault isolation and reduce the scope of fault impact.

[0070] In summary, the coordinated control method for grid-connected boundary switches provided in the above embodiments of the present invention has the following advantages:

[0071] (1) High system integration. It deeply integrates protection, monitoring, control and compensation functions to achieve comprehensive management and control of new energy grid connection points, avoids the coordination problem of single-function equipment, and improves the overall operating efficiency of the system.

[0072] (2) The island detection method that integrates multiple criteria effectively improves the accuracy and speed of island detection; the proactive early warning and adjustment strategy based on power quality data enables early intervention in the power grid operation status and reduces the probability of fault occurrence.

[0073] (3) Creatively proposed a four-level flexible control strategy of "alarm-remote adjustment-local compensation-final trip" to maximize the grid connection time of new energy power generation, reduce unnecessary grid disconnection, and improve the utilization rate of new energy while ensuring grid safety.

[0074] (4) It can actively support the power grid. The equipment breaks through the limitations of traditional passive protection and actively provides voltage and frequency support to the power grid through functions such as reactive power regulation, active power control and local reactive power compensation, thereby enhancing the power grid's ability to accept new energy sources.

[0075] This invention also provides a grid-connected boundary switch, which includes a main switching unit and a measurement and control unit; the main switching unit and the measurement and control unit are electrically connected.

[0076] The measurement and control unit is used to acquire the operation data of the grid connection point, monitor the operation status of the power grid based on the operation data, and intervene and regulate according to the level of abnormality if an abnormality is detected in the operation status of the power grid. The operation data includes at least the voltage, current, frequency, power and harmonic distortion rate of the grid connection point, and the monitoring items include at least islanding detection, power quality assessment and backfeed power monitoring.

[0077] The main switch unit is used to perform opening and closing operations under the control of the measurement and control unit, and to regulate corresponding abnormal states.

[0078] Specifically, grid-connected sectionalizing switches are used in medium- and low-voltage power grids. The switch body adopts a full circuit breaker structure, possessing excellent performance characteristics such as rapid opening and closing capability (opening time ≤10ms), low power consumption, high reliability, and long service life (mechanical life ≥30,000 cycles). The switch body and terminal interface conform to the digital input interface definition, ensuring the accuracy and compatibility of signal transmission. Simultaneously, the switch body, in conjunction with electronic sensors, achieves accurate acquisition of power grid operating parameters, providing reliable data support for subsequent protection and control functions.

[0079] The measurement and control unit has protection functions, including bidirectional overcurrent fault protection tripping. It adopts a three-stage protection configuration, allowing flexible setting of bidirectional protection action time limits and current settings to meet fault isolation requirements under different operating scenarios. The measurement and control unit is equipped with high-precision voltage and current transformers and sensors, which can accurately measure bidirectional power flow data, including key electrical quantities such as three-phase current, zero-sequence current, bidirectional (grid side and source side) three-phase phase voltage, and zero-sequence voltage. Among them, the basic error of grid side voltage measurement is not less than 0.5, and the basic error of source side voltage is not less than 3.

[0080] Meanwhile, the grid-connected boundary switch's measurement and control unit also integrates distributed power grid-connection protection functions such as islanding detection and anti-islanding protection, voltage and frequency over-limit protection, reverse power protection, and source-side voltage-controlled closing interlock, comprehensively covering various safety hazards in the process of new energy grid connection.

[0081] The measurement and control unit also integrates a power quality monitoring module for real-time monitoring of power quality indicators at the grid connection point. These include voltage deviation, voltage fluctuation and flicker, DC component, frequency deviation, three-phase voltage and current imbalance, voltage and current distortion rate, and voltage and current harmonics (2nd to 25th harmonic components). It can be set to record at least 160 waveforms per cycle, comprehensively recording electrical waveform data during faults and power quality anomalies, providing detailed evidence for power quality assessment and fault analysis. Monitoring data is uploaded to a local or remote management platform via a standardized interface, supporting power quality over-limit alarm functions. Alarm thresholds and confirmation times can be configured as needed.

[0082] Optionally, the measurement and control unit includes a communication management module; the communication management module includes a local communication interface and a remote communication submodule.

[0083] Specifically, the local communication interface within the communication management module is equipped with standard communication interfaces such as RS485 and Ethernet, enabling flexible connection with local monitoring systems or inverters. The remote communication submodule employs 4G / 5G or fiber optic communication technology to ensure the timely uploading of collected electrical quantity data, equipment operating status, and fault information to the cloud platform or dispatch master station. The communication protocol complies with the relevant requirements of the terminal communication protocol type, ensuring the standardization and reliability of data transmission.

[0084] Optionally, the measurement and control unit also includes a power module; the power module has an automatic battery activation submodule and a power fault detection submodule.

[0085] Specifically, the power module provides a stable power supply for the entire switch and is equipped with a backup battery pack to ensure that critical operations, such as fault tripping, data recording and uploading, can still be completed in the event of a power grid failure, thus ensuring the continuity of the system's core functions.

[0086] In addition to providing conventional operating power to the switch, the power module also includes an automatic battery activation submodule. This submodule features automatic battery activation, allowing for periodic activation of the battery by setting the activation cycle (in days) and activation time (0-23 hours), thus extending battery life. Furthermore, the power module includes a power fault detection submodule, which provides functions such as AC power loss detection, battery low-voltage alarm, and power module fault diagnosis, promptly reporting the operating status of the power system.

[0087] The grid-connected boundary switch provided in this embodiment of the invention uses the collaborative control method of the grid-connected boundary switch in the above embodiment. Therefore, the grid-connected boundary switch provided in this embodiment of the invention also has the beneficial effects described in the above embodiment, which will not be repeated here.

[0088] In the description of the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.

[0089] Finally, it should be noted that the above are merely preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A coordinated control method for a grid-connected boundary switch, characterized in that, The method includes: Obtain the operating data of the grid connection point where the grid connection boundary switch is located, wherein the operating data includes at least the voltage, current, frequency, power, and harmonic distortion rate of the grid connection point; The power grid's operating status is monitored based on the aforementioned operating data, and the monitoring items include at least islanding detection, power quality assessment, and backfeed power monitoring. If an abnormality is detected in the operation of the power grid, intervention and control will be carried out according to the level of the abnormality.

2. The coordinated control method for grid-connected boundary switches according to claim 1, characterized in that, While monitoring the operating status of the power grid based on the aforementioned operating data, the method also includes: The timing of data reporting is determined based on the operating data and the preset dead zone threshold, wherein the preset dead zone threshold includes at least the current change dead zone threshold, the AC voltage change dead zone threshold, the DC voltage change dead zone threshold, and the power change dead zone threshold.

3. The coordinated control method for grid-connected boundary switches according to claim 1, characterized in that, Monitoring the power grid's operational status based on the aforementioned operational data includes: Based on the operational data, islanding detection of the power grid is performed using the active frequency offset method or the voltage phase jump detection method. Based on the operational data, the power grid is assessed for power quality using a preset power quality threshold. Based on the operational data, the reverse power transmission power of the power grid is monitored using a preset reverse power threshold.

4. The coordinated control method for grid-connected boundary switches according to claim 1, characterized in that, If an abnormality is detected in the operation of the power grid, intervention and control will be carried out according to the level of abnormality, including: If an abnormality is detected in the operation of the power grid and the abnormality level is Level 1, an audible and visual alarm will be issued and the abnormality information will be recorded. The Level 1 abnormality level is when the range of the threshold is less than the first set range or there is a situation that does not need to be processed within the first time period. If an abnormality is detected in the operation of the power grid and the abnormality level is level two, an adjustment command is sent to the new energy inverter through the local communication interface to perform remote power adjustment. The level two abnormality level is when an abnormality in power quality is detected or the operating parameters deviate from the threshold by a range greater than the first set range and less than the second set range. If an abnormality is detected in the operation of the power grid and the abnormality level is three, local reactive power compensation is performed using preset parallel reactors or capacitor banks to stabilize the grid connection point voltage. The level three abnormality level is a situation where communication with the inverter is impossible or remote adjustment is ineffective. If an abnormality is detected in the operation of the power grid and the abnormality level is four, a trip isolation operation will be performed. The level four abnormality level is a short circuit fault or a situation where the regulation measures of level one to three are ineffective.

5. The coordinated control method for grid-connected boundary switches according to claim 3, characterized in that, Islanding detection of the power grid using active frequency offset method or voltage phase jump detection method includes: Islanding detection of the power grid is performed by using the active frequency offset method or the voltage phase jump detection method, combined with the voltage frequency change setting and the islanding protection delay setting.

6. The coordinated control method for grid-connected boundary switches according to claim 3, characterized in that, The power quality assessment references include at least one of the following: harmonic distortion rate, voltage deviation, and three-phase imbalance.

7. The coordinated control method for grid-connected boundary switches according to claim 3, characterized in that, After monitoring the reverse power transmission of the power grid using a preset reverse power threshold, the method further includes: If the power transmitted back to the grid by new energy generation exceeds the preset reverse power threshold, and the range of exceeding the threshold is less than the first set range, an alarm will be issued and abnormal status information will be recorded. If the power transmitted back to the grid by the new energy power generation exceeds the preset reverse power threshold, and the power continues to exceed the threshold for a period of time that reaches a first preset duration, then a stepped power reduction control or trip protection will be implemented.

8. A grid-connected boundary switch, characterized in that, The switch includes a main switch unit and a measurement and control unit; The main switch unit and the measurement and control unit are electrically connected; The measurement and control unit is used to acquire the operation data of the grid connection point, monitor the operation status of the power grid based on the operation data, and if an abnormality is detected in the operation status of the power grid, intervention and control are carried out according to the level of abnormality. The operation data includes at least the voltage, current, frequency, power and harmonic distortion rate of the grid connection point, and the monitoring items include at least islanding detection, power quality assessment and backfeed power monitoring. The main switch unit is used to perform opening and closing operations under the control of the measurement and control unit, and to regulate corresponding abnormal states.

9. The grid-connected boundary switch according to claim 8, characterized in that, The measurement and control unit includes a communication management module; The communication management module includes a local communication interface and a remote communication submodule.

10. The grid-connected boundary switch according to claim 8, characterized in that, The measurement and control unit also includes a power module; The power module includes an automatic battery activation submodule and a power fault detection submodule.

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