Micro-grid communication-free load sectionalization power restoration method, system, medium and product

Abstract

The application discloses a kind of microgrid no communication load section power supply recovery method, system, medium and product, the present application method includes in the microgrid power failure after by energy storage converter dominated section power supply system composition, network type energy storage converter restart, according to the output apparent power of network type energy storage converter output voltage instruction of network type energy storage converter adjustment;After network type energy storage converter restart, the intelligent switch of each section of section power supply system detects energy storage terminal voltage, when meeting energy storage terminal voltage is higher than closing voltage and maintains closing time, intelligent switch closing restores its next section load power supply, otherwise, do not act;Closing voltage meets preset constraint condition.The present application aims at realizing no communication can be realized quickly after power failure occurs Load section power supply recovery, reduce load loss, improve the power supply reliability of microgrid.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of micro-grid power supply recovery, and particularly relates to a micro-grid communication-free load segmented power supply recovery method, system, medium and product. BACKGROUND

[0002] At present, distributed new energy has been scaled into the distribution network. Due to the volatility and intermittency of distributed new energy output, the power mismatch between the distributed new energy and the local load will cause problems such as high and low voltage limit and positive and negative reverse overload of distribution transformers. To this end, configuring a certain capacity of energy storage at the transformer area side can effectively smooth the fluctuation of distributed new energy output, improve the distributed new energy consumption capacity at the transformer area side, and solve the above power supply problems. In addition, energy storage is also widely used in micro-grids to achieve power balance and emergency power supply in emergency situations. When the development of natural disasters causes line faults, the energy storage at the transformer area side under network control still has the potential to provide frequency and voltage support, which can support the normal operation of the load and distributed new energy within a certain range. Limited by the capacity of the energy storage converter, it is necessary to determine the operation and recovery area according to the fault position and "source and load" distribution to avoid overloading and burning of the energy storage converter. However, the current research on network power supply using distributed resources and transformer area energy storage under fault adopts centralized control, which requires additional control terminals and stable communication to control the load switches that divide the power supply area. On the one hand, the communication link of the control terminal required by such centralized control will introduce additional costs; on the other hand, when external factors damage the communication link, the centralized control method cannot be implemented. SUMMARY

[0003] The technical problem solved by the present application: In view of the above problems of the prior art, the present application provides a micro-grid communication-free load segmented power supply recovery method, system, medium and product, which aims to quickly realize load segmented power supply recovery after a power failure without communication, reduce load loss, and improve the power supply reliability of the micro-grid.

[0004] To solve the above technical problems, the technical scheme adopted by the present application is:

[0005] A micro-grid communication-free load segmented power supply recovery method, comprising: after a micro-grid composed of a segmented power supply system dominated by an energy storage converter is powered off, restarting the network-forming energy storage converter, and according to the output apparent power of the network-forming energy storage converter adjusting the output voltage instruction of the network-forming energy storage converter; after the network-forming energy storage converter is restarted, the intelligent switch of each segment of the segmented power supply system detects the energy storage end voltage When the energy storage end voltage is higher than the closing voltage and the closing time is maintained , the intelligent switch closes to restore power supply to the next segment of load, otherwise it does not act; the closing voltage satisfies:

[0006] ;

[0007] wherein, is the reference output voltage of the grid-forming energy storage converter, is the overload voltage droop coefficient, is a constant parameter less than 1, is a constant parameter less than 1 and greater than is a constant parameter less than 1 and greater than is the rated power of the grid-forming energy storage converter.

[0008] Optionally, the energy storage converter dominated sectionalized power supply system comprises an energy storage battery, a grid-forming energy storage converter, an AC line and an intelligent switch, the energy storage battery and the DC side of the grid-forming energy storage converter are connected to provide active power and absorb reactive power for a microgrid, the AC side of the grid-forming energy storage converter is connected to the AC line, the AC line is a single-chain network topology, and the intelligent switch of each section is connected in series on the main line of the AC line to divide the loads and distributed power sources connected on the main line into multiple groups, the energy storage terminal voltage V bat refers to the voltage close to the grid-forming energy storage converter end detected by the intelligent switch.

[0009] Optionally, the output apparent power of the grid-forming energy storage converter adjusting the output voltage instruction of the grid-forming energy storage converter comprises: when the output apparent power of the grid-forming energy storage converter is less than or equal to , the output voltage instruction of the grid-forming energy storage converter is adjusted to:

[0010] ;

[0011] wherein, is the output voltage instruction of the grid-forming energy storage converter; when the output apparent power of the grid-forming energy storage converter is greater than and less than , the output voltage instruction of the grid-forming energy storage converter is adjusted to:

[0012] ;

[0013] when the output apparent power of the grid-forming energy storage converter is greater than and less than , the output voltage instruction of the grid-forming energy storage converter is adjusted to:

[0014] ;

[0015] wherein, is a long-time overload multiple of the grid-forming energy storage converter with a value greater than 1, is a heavy overload voltage droop coefficient; when the output apparent power of the grid-forming energy storage converter is greater than and the duration , the grid-forming energy storage converter starts overload protection shutdown, and if the preset longest recovery time T t the grid-forming energy storage converter is restarted after being locked out due to overload protection shutdown.

[0016] Optionally, it further comprises, for the smart switch that has been automatically closed, when the energy storage end voltage is lower than the tripping voltage and the tripping time is maintained , the smart switch is opened and the reclosing is locked out, the tripping voltage satisfies:

[0017]

[0018] wherein, is a long-time overload multiple of the grid-forming energy storage converter with a value greater than 1, is a heavy overload voltage droop coefficient.

[0019] Optionally, it further comprises, for the smart switch that has been automatically closed, when the energy storage end voltage is lower than the fast tripping voltage and the fast tripping time is maintained , the smart switch is opened and the reclosing is locked out, wherein the fast tripping voltage is less than the tripping voltage , the preset fast tripping time is maintained is less than the tripping time , and the fast tripping voltage satisfies:

[0020]

[0021] wherein, is a heavy overload voltage droop coefficient.

[0022] Optionally, in the segmental power supply system dominated by the energy storage converter, the tripping time of each smart switch successively decreases according to the order from near to far from the grid-forming energy storage converter, and the tripping time of the smart switch farthest from the grid-forming energy storage converter is greater than the grid-connected starting time of the distributed power supply of each segment of the segmental power supply system.

[0023] Optionally, the smart switch closing voltage , opening voltage and fast opening voltage are compensated for the voltage drop caused by active and reactive power transmission on long lines, which is the voltage drop caused by active and reactive power transmission on long lines added to the original voltage , the calculation steps of the voltage drop include:

[0024] S101, obtain the line impedance of the main line in the segmented power supply system , the energy storage output voltage , the initial line apparent power , the estimated load power behind the smart switch , initialize the smart switch voltage in the initial stage , the energy storage output voltage , the loop variable k is 1; wherein, is the line resistance, is the line reactance, is the imaginary unit; is the active power, is the reactive power;

[0025] S102, calculate the line load current in the k-1 stage and the smart switch voltage in the current stage according to the following formula:

[0026] , ;

[0027] wherein, is the line load current in the k-1 stage, represents the conjugate complex of , and is the smart switch voltage in the k-1 stage; is the line apparent power in the k-1 stage, is the smart switch voltage in the current stage, is the energy storage output voltage, is the line impedance of the main line in the segmented power supply system; the line voltage drop and the power loss on the line in the k-1 stage are calculated according to the following formula:

[0028] , ;

[0029] S103, calculate the line apparent power in the k stage according to the following formula:

[0030] ;​

[0031] in, The apparent power of the line in stage k;

[0032] S104, Determine the intelligent switching voltage of stage k. Intelligent switching voltage in the k-1 stage The absolute value of the difference between them, if the absolute value is greater than or equal to a preset threshold. If the loop variable k is incremented by 1, the process jumps to step S102; otherwise, the pressure drop is calculated according to the following formula. And output:

[0033]

[0034] in, for The absolute value, for The absolute value of.

[0035] The present invention also provides a microgrid segmented power restoration system for non-communication loads, comprising a microprocessor and a memory interconnected thereto, wherein the microprocessor is programmed or configured to execute the microgrid segmented power restoration method for non-communication loads.

[0036] The present invention also provides a computer-readable storage medium storing a computer program or instructions that are programmed or configured to execute the microgrid segmented power supply restoration method for non-communication loads via a processor.

[0037] The present invention also provides a computer program product, including a computer program or instructions, which are programmed or configured to execute the microgrid no-communication load segmented power supply restoration method via a processor.

[0038] Compared with existing technologies, the present invention mainly achieves the following beneficial effects: The microgrid segmented power supply restoration method without communication load in the present invention includes restarting the grid-type energy storage converter, based on the apparent output power of the grid-type energy storage converter. The system sends commands to adjust the output voltage of the grid-type energy storage converter; after the grid-type energy storage converter restarts, the intelligent switches of each segment of the segmented power supply system detect the voltage at the energy storage terminal. When the energy storage terminal voltage is satisfied Higher than the closing voltage And maintain the closing time The intelligent switch will restore power to the subsequent load segment when it closes; otherwise, it will not operate. By coordinating the "power-voltage" curve in the energy storage with the pre-set trigger events in the intelligent switch, it can quickly restore power to the load segment after a power outage without communication, reducing load loss and improving power supply reliability. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the basic process of the method in an embodiment of the present invention.

[0040] Figure 2 This is a schematic diagram of a segmented power supply system dominated by an energy storage converter in an embodiment of the present invention.

[0041] Figure 3 This is a graph showing the output power of the energy storage converter in an embodiment of the present invention.

[0042] Figure 4 This is a graph showing the output voltage of the grid-type energy storage converter in an embodiment of the present invention.

[0043] Figure 5 This is a graph of the load-side voltage of the smart switch #1 in this embodiment of the invention.

[0044] Figure 6 This is a graph showing the load-side voltage of the smart switch #2 in this embodiment of the invention. Detailed Implementation

[0045] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be further described in detail below with reference to the accompanying drawings in the embodiments of the present invention.

[0046] like Figure 1 As shown, the microgrid power restoration method for segmented power supply without communication load in this embodiment includes restarting the grid-type energy storage converter after a power outage in a microgrid consisting of a segmented power supply system dominated by an energy storage converter, based on the apparent power output of the grid-type energy storage converter. The system sends commands to adjust the output voltage of the grid-type energy storage converter; after the grid-type energy storage converter restarts, the intelligent switches of each segment of the segmented power supply system detect the voltage at the energy storage terminal. When the energy storage terminal voltage is satisfied Higher than the closing voltage And maintain the closing time The intelligent switch will restore power to the subsequent load segment when it closes; otherwise, it will not operate; closing voltage satisfy:

[0047] ;

[0048] in, This is the reference output voltage for the grid-type energy storage converter. This is the heavy load voltage droop factor. For constant parameters less than 1, less than 1 and greater than constant parameters, This refers to the rated power of the grid-type energy storage converter.

[0049] like Figure 2 As shown, the segmented power supply system dominated by the energy storage converter in this embodiment includes energy storage batteries (such as...). Figure 2 As shown in Figure a), grid-type energy storage converters (such as...) Figure 2 As shown in b), AC lines (such as...) Figure 2 (as shown in c) and smart switches (such as Figure 2 As shown in Figure d), the energy storage battery is connected to the DC side of the grid-type energy storage converter to provide active power and absorb reactive power for the microgrid. The AC side of the grid-type energy storage converter is connected to an AC line, which is a single-chain network topology. The smart switches of each segment are connected in series on the main line of the AC line, dividing the loads and distributed power sources connected to the main line into multiple groups (e.g., ...). Figure 2 (E is a group of loads and distributed power sources), the voltage of the energy storage terminal is shown in Figure e. V bat This refers to the voltage detected by the smart switch near the grid-type energy storage converter. The energy storage battery provides active power support to the system, including providing the active power required by the load and absorbing active power generated by distributed renewable energy sources. The grid-type energy storage converter connects to the energy storage battery output at one end and to an AC line at the other, converting the DC power output from the energy storage battery into AC power. The AC line is a single-chain network topology, connecting the grid-type energy storage converter to distributed power sources and loads within the area. The smart switch is connected in series on the main AC line, dividing the load and distributed renewable energy sources into several areas. In a single system, no more than three smart switches should be used. In this embodiment, the end closer to the grid-type energy storage converter is defined as the energy storage end, and the end farther from the grid-type energy storage converter is defined as the load end. After a system power outage, all smart switches detect no voltage and automatically disconnect.

[0050] In this embodiment, based on the apparent output power of the grid-type energy storage converter... The commands for adjusting the output voltage of the grid-connected energy storage converter include: when the apparent power output of the grid-connected energy storage converter... Less than or equal to At that time, the output voltage command for adjusting the grid-type energy storage converter is:

[0051] ;

[0052] in, This refers to the output voltage command of the grid-connected energy storage converter; when the output apparent power of the grid-connected energy storage converter... Greater than and less than When this situation is defined as overload, k 1< k2<1, on the basis of the original voltage droop control curve, increase an additional "power-voltage droop" curve, that is, adjust the output voltage instruction of the grid-forming energy storage converter:

[0053] ;

[0054] When the output apparent power of the grid-forming energy storage converter is greater than and less than , the case is defined as heavy overload, k 3 is the long-time overload multiple of the grid-forming energy storage converter, k 2<1 k 3, adjust the output voltage instruction of the grid-forming energy storage converter:

[0055] ;

[0056] Wherein, 3 is the long-time overload multiple of the grid-forming energy storage converter with a value greater than 1, is a heavy overload voltage droop coefficient; when the output apparent power of the grid-forming energy storage converter is greater than and the duration , the grid-forming energy storage converter starts overload protection shutdown, and if the preset longest recovery time T t The grid-forming energy storage converter is restarted after being locked out due to overload protection shutdown.

[0057] In the embodiment, the smart switch that has been automatically closed is also included, when the energy storage end voltage is detected to be lower than the tripping voltage and the tripping time is maintained, the smart switch is opened and the reclosing is locked out, and the tripping voltage satisfies:

[0058]

[0059] Wherein, 3 is the long-time overload multiple of the grid-forming energy storage converter with a value greater than 1, is a heavy overload voltage droop coefficient.

[0060] When the load is very heavy and the voltage drops to the fast tripping voltage (the fast tripping voltage is less than the tripping voltage ), the switch is fast tripped, and the maintenance time is shorter, that is, the fast tripping time is less than the tripping time . Therefore, in the embodiment, the smart switch that has been automatically closed is also included, when the energy storage end voltage Lower than the fast opening voltage And maintain the fast opening time When the intelligent switch is off, and the reclosing is locked out, the fast opening voltage Satisfies:

[0061]

[0062] Wherein, Is the overloading voltage droop coefficient.

[0063] For the scene of dividing the AC line into multiple sections for power supply by using more than two intelligent switches, the opening time of each intelligent switch Should be different. In the segmented power supply system dominated by the energy storage converter in this embodiment, the opening time corresponding to each intelligent switch According to the order from near to far from the distance of the intelligent switch to the off-grid network type energy storage converter, and the opening time corresponding to the intelligent switch farthest from the off-grid network type energy storage converter Is greater than the grid-connected start-up time of the distributed power supply of each section of the segmented power supply system. For example, the intelligent switches are numbered from near to far from the off-grid network type energy storage converter, which are Q 1, Q 2 to Q n , and the opening time corresponding to them is T open1 , T open2 to T openn , which should satisfy T openn <......< T open2 < T open1 , and T openn Should be greater than the grid-connected start-up time of the distributed power supply. Similarly, the closing time of each intelligent switch is T close1 , T close2 to T closen .

[0064] For the case where the AC line is long, the voltage drop caused by the transmission of active and reactive power on the long line needs to be considered, so as an optional embodiment, this embodiment also includes considering the influence of active and reactive power on the long line and the inductance and resistance of the low-voltage line. The closing voltage , opening voltage And fast opening voltage compensation of the voltage drop caused by long-line active and reactive power transmission in part or all of the section power supply system, the compensation being an increase in the voltage drop caused by long-line active and reactive power transmission on the basis of the original voltage , the calculation step of the voltage drop comprises:

[0065] S101, obtaining the line impedance of the main line in the section power supply system , the energy storage output voltage , the initial line apparent power , the estimated load power after the intelligent switch , initializing the intelligent switch voltage in the initial stage , the energy storage output voltage , the loop variable k is 1; wherein, is the line resistance, is the line reactance, is the imaginary unit; is the active power, is the reactive power;

[0066] S102, calculating the line load current in the k-1 stage and the intelligent switch voltage in the current stage according to the following formula:

[0067] , ;

[0068] wherein, is the line load current in the k-1 stage, represents the conjugate complex number, is the intelligent switch voltage in the k-1 stage; is the line apparent power in the k-1 stage, is the intelligent switch voltage in the current stage, is the energy storage output voltage, is the line impedance of the main line in the section power supply system; the line voltage drop in the k-1 stage and the power loss on the line are calculated according to the following formula: :

[0069] , ;

[0070] S103, calculating the line apparent power in the k stage according to the following formula: :

[0071] ;

[0072] wherein, is the line apparent power in the k stage; ​

[0073] S104, Determine the intelligent switching voltage of stage k. Intelligent switching voltage in the k-1 stage The absolute value of the difference between them, if the absolute value is greater than or equal to a preset threshold. If the loop variable k is incremented by 1, the process jumps to step S102; otherwise, the pressure drop is calculated according to the following formula. And output:

[0074]

[0075] in, for The absolute value, for The absolute value of.

[0076] To verify the feasibility of the microgrid segmented power supply restoration method without communication loads in this embodiment, this embodiment is based on Figure 2 The topology of a segmented power supply system dominated by an energy storage converter is simulated. Specifically, this system is divided into three segments by two smart switches (smart switch #1 and smart switch #2), with smart switch #1 located on the side closest to the energy storage converter. To simplify the analysis, only the load and distributed generation are considered. The parameters set in the simulation include: S n It is 10 kW. k 1 is 0.75. k 2 is 0.95, k 3 is 1.1. K v1 It is 8. K v2 It is 10. V 0 is 220 V. T close1 For 1 s, T close2 For 1 s, V close It is 208 V. T open1 It takes 0.3 seconds. T open2 It is 0.1s. V open The voltage is 198 V. The final simulation waveform for the segmented restoration of power to the load after a power outage is as follows: Figures 3-6 As shown. Among them, Figure 3 This is a graph showing the output power of the energy storage converter in this embodiment. Figure 4 This is a graph showing the output voltage of the grid-type energy storage converter in this embodiment. Figure 5 This is a graph showing the load-side voltage of smart switch #1 in this embodiment.Figure 6 The graph of the voltage on the load side of the intelligent switch #2 in this embodiment is shown. As shown, after the power failure, the energy storage restores the power supply, and a 5 kW local load is connected. As shown in FIG. 6 and FIG. 7, the intelligent switch #1 detects that the voltage on the energy storage side is greater than 400 V, and the intelligent switch #1 is closed, thereby restoring the power supply of the 3.5 kW load on the back end of the intelligent switch #1, and entering the heavy load interval, and the line voltage slightly decreases under the influence of the droop curve. Then, as shown in FIG. 8 and FIG. 9, the intelligent switch #2 detects that the voltage on the energy storage side is greater than 400 V, and the intelligent switch #2 is closed, thereby restoring the power supply of the 1.2 kW load on the back end of the intelligent switch #2. At the fourth second, the load on the back end of the intelligent switch #2 suddenly increases to 23 kW, and the line voltage greatly decreases, and the voltage on the back end of the intelligent switch #2 is maintained at 400 V. After the voltage on the back end of the intelligent switch #2 is maintained at 400 V, the intelligent switch #2 is opened, and the reclosing is locked. The simulation results prove the feasibility of the load segmented power supply restoration method of the micro-grid without communication in this embodiment. Figure 3 Figure 4 Figure 5 V close T close1 Figure 4 Figure 6 V close T close2 T open2

[0077] In summary, the load segmented power supply restoration method of the micro-grid without communication in this embodiment is matched with the trigger event pre-set in the intelligent switch through the "power-voltage" curve in the energy storage, and the load segmented power supply restoration can be realized without communication. On the premise of avoiding overloading and burning of the energy storage converter, the load power supply is restored immediately after the power failure, and the power supply reliability is improved. Compared with the existing research, the centralized control terminal and the communication link are omitted, the cost is lower, the risk of failure of the centralized control caused by the communication disconnection under the influence of external factors is avoided, and the reliability is higher.

[0078] In addition, the embodiment also provides a micro-grid load segmented power supply restoration system without communication, which comprises a microprocessor and a memory connected with each other, and the microprocessor is programmed or configured to execute the micro-grid load segmented power supply restoration method without communication. The embodiment also provides a computer readable storage medium, which stores a computer program or instructions programmed or configured to execute the micro-grid load segmented power supply restoration method without communication through a processor. The embodiment also provides a computer program product, which comprises a computer program or instructions programmed or configured to execute the micro-grid load segmented power supply restoration method without communication through a processor.

[0079] ​​​​​​​​​​Those skilled in the art will appreciate that the technology provided herein is not limited to any particular form of implementation. The technology provided herein can be implemented in hardware, software, or a combination thereof. Those skilled in the art will appreciate that the technology provided herein can be implemented in a number of different embodiments, including method embodiments, system embodiments, and computer program product embodiments. The technology provided herein can be implemented in any combination of hardware, software, or a combination thereof. The technology provided herein can be implemented in a number of different ways, including as a computer program product stored on a computer readable storage medium, as a system on chips (SOCs), as an application specific integrated circuit (ASIC), or as a combination of the above. The technology provided herein can be implemented using any suitable hardware, software, firmware, or combination thereof. The technology provided herein can be implemented in one or more computer programs or one or more articles of manufacture that contain computer readable program code. The technology provided herein can be implemented using any suitable computer readable storage medium, including storage devices that are external or internal to a computer. Suitable computer readable storage mediums can include, but are not limited to, volatile memory, non-volatile memory, removable storage, and non-removable storage. Suitable computer readable storage mediums can include, but are not limited to, RAM, ROM, EEPROM, flash memory, or any other memory technology. Suitable computer readable storage mediums can include, but are not limited to, magnetic cassettes, magnetic tapes, magnetic disks, memory cards or sticks, optical storage media, or any other storage medium suitable for storing computer readable program code. The computer readable program code can be executed using any suitable computer processor, including a general purpose computer, a special purpose computer, an embedded computer, or any other computer. The computer readable program code can be executed using any suitable operating system, including a UNIX operating system, a LINUX operating system, a WINDOWS operating system, a MAC OS operating system, or any other operating system. The computer readable program code can be executed using any suitable computer programming language, including a high level programming language, a low level programming language, an object oriented programming language, a visual programming language, or any other computer programming language. Figure 1 one or more functions specified in the flow or flows and / or blocks Figure 1 one or more functions specified in the flow or flows and / or blocks Figure 1 one or more functions specified in the flow or flows and / or blocks Figure 1 one or more functions specified in the flow or flows and / or blocks Figure 1 one or more functions specified in the flow or flows and / or blocks Figure 1 one or more functions specified in the flow or flows and / or blocks

[0080] The above description is only preferred embodiments of the present application. The protection scope of the present application is not limited to the above-mentioned embodiments. Any technical scheme falling within the concept of the present application is within the protection scope of the present application. It should be noted that some improvements and refinements made by those skilled in the art without departing from the principle of the present application are also considered to be within the protection scope of the present application.

Claims

1. A method for microgrid communication-free load sectionalizing restoration, the method comprising: comprises: after the micro-grid constituted by the segmented power supply system dominated by the energy storage converter is powered off, the grid-forming energy storage converter is restarted, and according to the output apparent power of the grid-forming energy storage converter the output voltage instruction of the grid-forming energy storage converter is adjusted; after the grid-forming energy storage converter is restarted, the intelligent switch of each segment of the segmented power supply system detects the energy storage terminal voltage When the energy storage terminal voltage is higher than the closing voltage and the closing time is maintained, the intelligent switch is closed to restore the power supply of the subsequent segment load, otherwise, the intelligent switch is not operated; the closing voltage satisfies: ； wherein, is a reference output voltage of the grid-forming energy storage converter, is a heavy load voltage droop coefficient, is a constant parameter less than 1, is a constant parameter less than 1 and greater than , is a rated power of the grid-forming energy storage converter, the segmented power supply system dominated by the energy storage converter comprising an energy storage battery, a grid-forming energy storage converter, an alternating current line and an intelligent switch, the energy storage battery being connected to a direct current side of the grid-forming energy storage converter for providing active power and absorbing reactive power for a micro-grid, an alternating current side of the grid-forming energy storage converter being connected to the alternating current line, the alternating current line being a single-chain network topology, the intelligent switch of each segment being connected in series on a main line of the alternating current line, loads and distributed power sources connected on the main line being divided into multiple groups, the energy storage terminal voltage V bat is a voltage close to the grid-forming energy storage converter detected by the intelligent switch.

2. The method of claim 1, wherein, The output apparent power of the grid-connection type energy storage converter The output voltage instruction of the grid-connection type energy storage converter is adjusted to be: less than or equal to ​ ； wherein, is an output voltage instruction of the grid-forming energy storage converter; when an output apparent power of the grid-forming energy storage converter is greater than and less than , the output voltage instruction of the grid-forming energy storage converter is adjusted as: ； When the output apparent power of the grid-forming energy storage converter is greater than and less than , the output voltage instruction of the grid-forming energy storage converter is adjusted as: ； wherein, is a long-time overload multiple of the grid-forming energy storage converter with a value greater than 1, is a heavy overload voltage droop coefficient; when the output apparent power of the grid-forming energy storage converter is greater than and the duration , the grid-forming energy storage converter starts overload protection shutdown, if the preset longest recovery time T t the grid-forming energy storage converter is restarted after being locked out due to overload protection shutdown.

3. The method of claim 1, wherein, Also included is for the smart switch that has been automatically closed, when the detection of the energy storage end voltage is lower than the opening voltage and the opening time is maintained , the smart switch is opened, and the reclosing is locked out, the opening voltage satisfies: wherein, is a long-time overload multiple of the network-forming energy storage converter with a value greater than 1, is a heavy overload voltage droop coefficient.

4. The method of claim 3, wherein, Also included is a smart switch that has automatically closed when the energy storage terminal voltage is detected to be below a fast trip voltage and a fast trip time is maintained, wherein the fast trip voltage is less than the trip voltage and the pre-set fast trip time is less than the trip time , the fast trip voltage satisfies: wherein, is a heavy overload voltage droop coefficient.

5. The microgrid communication-less load sectionalizing restoration method of claim 1, wherein, The breaking time corresponding to each intelligent switch in the segmented power supply system dominated by the energy storage converter The breaking time corresponding to each intelligent switch in the segmented power supply system dominated by the energy storage converter The breaking time corresponding to each intelligent switch in the segmented power supply system dominated by the energy storage converter 6. The microgrid communication-less load sectionalizing restoration method of claim 4, wherein, This also includes the closing voltage of the smart switch. , tripping voltage and fast trip voltage Part or all of the voltage drop compensation caused by active and reactive power transmission over long lines is performed. This voltage drop compensation is achieved by adding the voltage drop caused by active and reactive power transmission over long lines to the original voltage. The voltage drop The calculation steps include: S101, obtaining line impedance of a trunk line in a segmented power supply system , energy storage output voltage , initial line apparent power , to estimate the back-end load power of the intelligent switch , initialize the initial stage intelligent switch voltage , energy storage output voltage , the loop variable k is 1; wherein, , line resistance, , line reactance, , imaginary unit; , active power, , reactive power; S102, calculate the line load current of k-1 stage and the intelligent switch voltage of this stage according to the following formula: ， ； wherein is the line load current at stage k-1, denotes the conjugate complex of is the smart switch voltage at stage k-1; is the line apparent power at stage k-1, is the smart switch voltage at the present stage, is the energy storage output voltage, is the line impedance of the main line in the segmented power supply system; the line voltage drop at stage k-1 is calculated according to the following formula and the power lost on the line : ， ； S103, calculate the line apparent power of the kth stage according to the following formula : ； wherein, Pline(k) is the apparent power of the line for k phase; S104, Determine the intelligent switching voltage of stage k. Intelligent switching voltage in the k-1 stage The absolute value of the difference between them, if the absolute value is greater than or equal to a preset threshold. If the loop variable k is incremented by 1, the process jumps to step S102; otherwise, the pressure drop is calculated according to the following formula. And output: wherein is the absolute value of is the absolute value of 7. A microgrid communication-less load sectionalizing power restoration system comprising a microprocessor and a memory interconnected, characterized in that, The microprocessor is programmed or configured to execute the microgrid non-communication load sectional power supply recovery method in any one of claims 1-6.

8. A computer-readable storage medium having stored therein a computer program or instructions, characterized in that, The computer program or instruction is programmed or configured to execute the microgrid non-communication load sectional power supply recovery method in any one of claims 1-6 by the processor.

9. A computer program product comprising computer programs or instructions, characterized in that, The computer program or instruction is programmed or configured to execute the microgrid non-communication load sectional power supply recovery method in any one of claims 1-6 by the processor. The computer program or instruction is programmed or configured to execute the microgrid non-communication load sectional power supply recovery method in any one of claims 1-6 by the processor.

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