Microgrid control method and apparatus, microgrid, and storage medium

Abstract

The present application discloses a microgrid control method and apparatus, a microgrid, and a storage medium. A power type energy storage device is connected within a microgrid, and the microgrid control method comprises: when it is determined that the microgrid is in an unplanned islanding mode, controlling the power type energy storage device to enter a power support mode, wherein the power type energy storage device charges and discharges the microgrid in the power support mode; when the power type energy storage device is in the power support mode, carrying out source-load power adjustment on the microgrid; and once the microgrid reaches a source-load power balance, controlling the power type energy storage device to exit the power support mode. According to the microgrid control method, during unplanned islanding of the microgrid, flexible source-load power adjustment can be carried out thereon within a relatively sufficient time frame, thereby ensuring the stable operation of the microgrid.

Description

Microgrid control method, control device, microgrid and storage medium

[0001] This application claims priority to a domestic application filed with the Patent Office of China on January 22, 2024, with application number 202410090870.6 and invention name “Microgrid control method, control device, microgrid and storage medium”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of microgrids, and in particular to a microgrid control method, a control device, a microgrid, and a storage medium. Background Art

[0003] A microgrid is a small-scale power generation and distribution system consisting of power sources, loads, distribution facilities, and monitoring and protection devices. Most microgrids can operate in both on-grid and off-grid modes. Microgrid on-grid and off-grid switching modes include planned (active) on-grid to off-grid, unplanned (passive) on-grid to off-grid, and planned (active) off-grid to on-grid.

[0004] Both planned on-grid transitions and planned off-grid transitions allow for manual adjustments to the microgrid's internal power output and load prior to operation. Only after achieving a source-load power balance can the mode switch be performed, thus avoiding the impact of power imbalance during the mode switchover process. For unplanned on-grid transitions, since disconnection from the public grid is an emergency, at the moment the on-grid / off-grid switch is disconnected, the microgrid not only needs to withstand the impact of the power imbalance within the microgrid, but also needs to use emergency control measures to quickly compensate for the system power imbalance caused by the passive off-grid transition. Currently, there is no effective response to unplanned off-grid microgrid disconnections.

[0005] Summary of the Invention

[0006] The present application provides a microgrid control method, a control device, a microgrid, and a storage medium. The microgrid can flexibly adjust the source and load power within a relatively sufficient time when it is unplanned off-grid, thereby ensuring the smooth operation of the microgrid.

[0007] In a first aspect, an embodiment of the present application provides a microgrid control method, wherein a power-type energy storage device is connected to the microgrid, and the microgrid control method includes: when it is determined that the microgrid is unplanned off-grid, controlling the power-type energy storage device to enter a power support mode, and the power-type energy storage device charges and discharges the microgrid in the power support mode; while the power-type energy storage device is in the power support mode, adjusting the source-load power of the microgrid; after the microgrid reaches source-load power balance, controlling the power-type energy storage device to exit the power support mode.

[0008] According to the aforementioned implementation of the first aspect of the present application, prior to the step of determining that the microgrid is in an unplanned off-grid state, the microgrid control method further includes: generating off-grid information of the microgrid based on the disconnection of a switch at the microgrid's common connection point; determining whether the microgrid is in a planned off-grid state based on the off-grid information; and maintaining the current operating state of the microgrid when the microgrid is determined to be in a planned off-grid state.

[0009] According to any of the aforementioned implementations of the first aspect of the present application, the maximum output or absorbed power of the power-type energy storage device is greater than the maximum power deficit generated by the microgrid within a source-load power adjustment cycle.

[0010] According to any of the foregoing embodiments of the first aspect of the present application, the microgrid includes a common connection point for connecting to a public power grid and a feeder network connected to the common connection point, wherein a power source, a power load and a non-power energy storage device are connected to the feeder network, wherein the power energy storage device is connected between the common connection point and the feeder network.

[0011] According to any of the aforementioned embodiments of the first aspect of the present application, the source-load power adjustment of the microgrid during the period when the power-type energy storage device is in the power support mode includes: real-time detection and acquisition of the power imbalance of the microgrid, the power imbalance is equal to the real-time output power of the power supply in the feeder network plus the real-time discharge power of the non-power-type energy storage device minus the real-time load rate of the power load and minus the real-time charging power of the non-power-type energy storage device; adjusting the real-time charging and discharging power of the power-type energy storage device according to the power imbalance; and adjusting the source-load power of the microgrid according to the power imbalance.

[0012] According to any of the aforementioned implementations of the first aspect of the present application, adjusting the real-time charging and discharging power of the power-type energy storage device according to the power imbalance includes: controlling the real-time charging and discharging power of the power-type energy storage device to be equal to the power imbalance.

[0013] According to any of the aforementioned implementations of the first aspect of the present application, the source-load power adjustment of the microgrid according to the power imbalance includes: when the power imbalance is positive, controlling the reduction of the output power of the power supply in the feeder network, and controlling the reduction of the discharge power of the non-power energy storage device in the feeder network until the power imbalance is zero.

[0014] According to any of the aforementioned implementations of the first aspect of the present application, the source-load power adjustment of the microgrid according to the power imbalance includes: when the power imbalance is negative, the source-load power adjustment is performed in the following order until the power imbalance is zero: controlling to increase the output power of the power source in the feeder network; controlling to reduce the charging power of the non-power energy storage device in the feeder network, and controlling to increase the discharge power of the non-power energy storage device in the feeder network; controlling to reduce the controllable load of the power load in the feeder network, and cutting off non-important loads in the power load.

[0015] In a second aspect, an embodiment of the present application provides a control device for a microgrid, wherein a power-type energy storage device is connected to the microgrid, and the control device for the microgrid includes: a power support mode startup module, which is used to control the power-type energy storage device to enter a power support mode when it is determined that the microgrid is unplanned off-grid, and the power-type energy storage device charges and discharges the microgrid in the power support mode; a source-load power adjustment module, which is used to adjust the source-load power of the microgrid while the power-type energy storage device is in the power support mode; and a power support mode exit module, which is used to control the power-type energy storage device to exit the power support mode after the microgrid reaches a source-load power balance.

[0016] In a third aspect, an embodiment of the present application provides a microgrid, comprising: a feeder network, to which a power supply, a power load, and a non-power energy storage device are connected; a common connection point, for connecting the feeder network to a public power grid; a power energy storage device, connected to the feeder network; a controller, connected to the feeder network, the common connection point, and the power energy storage device, the controller comprising a memory and at least one processor, the memory storing instructions, the at least one processor calling the instructions in the memory so that the controller executes the control method of any of the aforementioned implementations of the first aspect of the present application.

[0017] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium having instructions stored thereon, wherein when the instructions are executed by a processor, a microgrid control method according to any of the aforementioned embodiments of the first aspect of the present application is implemented.

[0018] According to the control method of the microgrid in the embodiment of the present application, a power-type energy storage device is connected to the microgrid. When it is determined that the microgrid is unplanned off-grid, the power-type energy storage device is controlled to enter the power support mode, and the power-type energy storage device can charge and discharge the microgrid in the power support mode. Due to the high charge and discharge rate of the power-type energy storage device, at the moment of unplanned off-grid, the power-type energy storage device releases or absorbs the unbalanced power in the microgrid, providing the microgrid with power support of seconds to minutes, so that the microgrid dispatching and control system can switch the working mode of the original energy storage system within a relatively sufficient time, flexibly adjust the power output and load demand in the microgrid, meet the power balance while reducing transient disturbances, thereby ensuring the safe and stable operation of the microgrid when it is off-grid. The above-mentioned adjustment method for responding to planned off-grid of the microgrid can achieve better control effect and control reliability while reducing the requirements for the response speed of the communication, control device and power electronic device in the microgrid control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0020] FIG1 is a flow chart of an embodiment of a microgrid control method of the present application;

[0021] FIG2 is a schematic structural diagram of an embodiment of a control device for a microgrid according to the present application;

[0022] FIG3 is a schematic diagram of the hardware structure of a microgrid in an embodiment of the present application;

[0023] FIG4 is a schematic diagram of the hardware structure of a controller in an embodiment of a microgrid of the present application.

[0024] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0026] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0027] In addition, the descriptions of "first", "second", etc. in this application are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0028] A microgrid is a small-scale power generation and distribution system consisting of power sources, loads, distribution facilities, and monitoring and protection devices. Most microgrids can operate in both on-grid and off-grid modes. Microgrid on-grid and off-grid switching modes include planned (active) on-grid to off-grid, unplanned (passive) on-grid to off-grid, and planned (active) off-grid to on-grid.

[0029] Planned grid-connection and off-grid transition means: the microgrid is pre-adjusted to a source-load power balance state within the microgrid, the power exchanged with the public grid approaches zero, and then the off-grid command is actively triggered, and a smooth active grid-connection and off-grid transition process is achieved through a seamless switching strategy.

[0030] Unplanned grid-connection and off-grid switching means that when a fault occurs in the public grid, the microgrid is passively disconnected from the grid, and the on-grid and off-grid switch between the microgrid and the public grid is disconnected. The source and load power in the microgrid need to be adjusted quickly to ensure safe and stable operation in the island state.

[0031] Planned off-grid and grid-connected means that when the public grid fault is eliminated, the microgrid is connected to the public grid through quasi-synchronous operation, thereby improving the power supply reliability of the microgrid.

[0032] The switching of microgrid between grid-connected and off-grid operation modes will directly affect the safety and stability of the microgrid. Therefore, how to ensure the safety and stability of the microgrid during the switching process between grid-connected and off-grid is a key issue in microgrid operation control technology.

[0033] In the above three on-grid and off-grid switching modes, planned on-grid to off-grid and planned off-grid to on-grid, both can manually adjust the power output and load size inside the microgrid before operation, and then perform the mode switching operation after reaching the source-load power balance state, thereby avoiding the power imbalance impact during the mode switching process.

[0034] For unplanned grid-connection and off-grid switching, since disconnection from the public grid is an emergency, at the moment the grid-connection and off-grid switching switch is disconnected, the microgrid not only needs to withstand the impact of the power imbalance within the microgrid at that moment, but also needs to quickly compensate for the system power imbalance caused by passive off-grid through emergency control measures. Microgrids with energy storage devices as the main power source also need to switch the energy storage working mode from grid-following type to grid-forming type.

[0035] Currently, there are two common approaches to addressing unplanned microgrid disconnections: one is to implement emergency control measures (such as load disconnection) based on the power imbalance at the time of disconnection to achieve power balance between the source and load within the microgrid. This approach places high demands on the response speed of communications, control devices, and power electronics (all response times must be controlled within 100 milliseconds). Furthermore, the implementation of control measures can introduce new transient disturbances to the microgrid system. Even if the microgrid system eventually reaches a new equilibrium state, the system's voltage and frequency will experience significant oscillations during the transient process, affecting the power supply quality of the microgrid's loads and preventing seamless switching from grid-connected to off-grid. This approach is particularly prone to control failure when the power shortfall is large (e.g., exceeding 20% ​​of the microgrid's total load). Another approach is to quickly trip the peripheral switches between the energy storage device and the critical load branch circuit according to a predetermined strategy once an unplanned off-grid event is detected. This also trips the peripheral switches between all other loads and distributed power sources that have already implemented anti-islanding protection, leaving only the connecting line between the energy storage device and the critical load. This ensures the normal and stable operation of the energy storage device and the critical load branch circuit, providing uninterrupted power supply to the critical load. However, this approach can cause other loads in the microgrid to lose power directly, causing the distributed power source to go offline due to a fault, thus reducing the reliability of the microgrid's power supply.

[0036] The present invention provides a control method for a microgrid. In this embodiment, the microgrid can be a power grid that integrates power generation, grid-load, and storage, a zero-carbon park, or a photovoltaic, storage, and charging integrated power station, which is connected to the public grid through a point of common coupling (PCC) and has off-grid self-operation capabilities.

[0037] FIG1 is a flow chart of an embodiment of a microgrid control method of the present application. A power storage device 220 is connected to the microgrid, such as a supercapacitor or a flywheel energy storage device. The microgrid control method includes steps S110 to S160.

[0038] In step S110 , based on the disconnection of the switch of the common connection point of the microgrid, off-grid information of the microgrid is generated.

[0039] In step S120 , based on the off-grid information, it is determined whether the microgrid is off-grid in a planned manner.

[0040] In step S130 , when it is determined that the microgrid is planned to be off-grid, the current operating state of the microgrid is maintained.

[0041] In step S140 , when it is determined that the microgrid is unplanned off-grid, the power-type energy storage device is controlled to enter a power support mode, and the power-type energy storage device charges and discharges the microgrid in the power support mode.

[0042] In step S150 , while the power type energy storage device is in the power support mode, source-load power adjustment is performed on the microgrid.

[0043] While the power-type energy storage device is in the power support mode, the power-type energy storage device charges and discharges the microgrid to temporarily maintain power balance within the microgrid.

[0044] In step S160 , after the microgrid reaches source-load power balance, the power-type energy storage device is controlled to exit the power support mode.

[0045] In some embodiments, a microgrid includes a common connection point for connecting to a public power grid and a feeder network connected to the common connection point. The feeder network is connected to power sources, loads, and non-power energy storage devices. The power energy storage device is connected between the common connection point and the feeder network. Because the power energy storage device is located near the common connection point, communication latency can be minimized, resulting in response times of less than 10ms, enabling seamless on-grid and off-grid switching.

[0046] In some embodiments, the maximum output or absorption power of the power-type energy storage device is greater than the maximum power deficit generated by the microgrid during a source-load power adjustment cycle.

[0047] In some embodiments, the duration of power-type energy storage in power support mode can be determined based on the time required to switch to the main power mode within the microgrid and the time required for the source-load power adjustment process. The main power mode switch refers to the need to switch the energy storage system from grid-following mode to grid-forming mode if the energy-type energy storage device serves as the main power source during off-grid operation.

[0048] In some embodiments, the step S150 of adjusting the source-load power of the microgrid during the power support mode of the power storage device includes: detecting and obtaining the power imbalance P of the microgrid in real time, where the power imbalance P is equal to the real-time output power P of the power source in the feeder network. 源 Plus the real-time discharge power P of non-power energy storage equipment 储放 Subtract the real-time load rate P of the power load 荷 And minus the real-time charging power P of non-power energy storage equipment 储充, where non-power type energy storage devices refer to other energy storage devices in the microgrid except the above-mentioned power type energy storage devices; the real-time charging and discharging power of the power type energy storage devices is adjusted according to the power imbalance P; the source and load power of the microgrid is adjusted according to the power imbalance P.

[0049] In some embodiments, the step of adjusting the real-time charge and discharge power of the power-type energy storage device according to the power imbalance P specifically includes: controlling the real-time charge and discharge power of the power-type energy storage device to be equal to the power imbalance P.

[0050] In some embodiments, the above-mentioned step of adjusting the source-load power of the microgrid according to the power imbalance P includes: when the power imbalance P is positive, controlling the reduction of the output power of the power supply in the feeder network, and controlling the reduction of the discharge power of the non-power energy storage device in the feeder network until the power imbalance P is zero.

[0051] In some embodiments, the above-mentioned step of adjusting the source-load power of the microgrid according to the power imbalance P includes: when the power imbalance P is negative, adjusting the source-load power in the following order until the power imbalance P is zero: controlling to increase the output power of the power source in the feeder network; controlling to reduce the charging power of the non-power energy storage device in the feeder network, and controlling to increase the discharge power of the non-power energy storage device in the feeder network; controlling to reduce the controllable load of the power load in the feeder network, and cutting off non-important loads in the power load.

[0052] According to the control method of the microgrid in the embodiment of the present application, a power-type energy storage device is connected to the microgrid. When it is determined that the microgrid is unplanned off-grid, the power-type energy storage device is controlled to enter the power support mode, and the power-type energy storage device can charge and discharge the microgrid in the power support mode. Due to the high charge and discharge rate of the power-type energy storage device, at the moment of unplanned off-grid, the power-type energy storage device releases or absorbs the unbalanced power in the microgrid, providing the microgrid with power support of seconds to minutes, so that the microgrid dispatching and control system can switch the working mode of the original energy storage system within a relatively sufficient time, flexibly adjust the power output and load demand in the microgrid, meet the power balance while reducing transient disturbances, thereby ensuring the safe and stable operation of the microgrid when it is off-grid. The above-mentioned adjustment method for responding to planned off-grid of the microgrid can achieve better control effect and control reliability while reducing the requirements for the response speed of the communication, control device and power electronic device in the microgrid control system.

[0053] The present application also provides a microgrid control device. Figure 2 is a schematic diagram of the structure of one embodiment of the microgrid control device of the present application. A power-type energy storage device is connected to the microgrid. The microgrid control device includes a power support mode activation module 140, a source-load power adjustment module 150, and a power support mode exit module 160.

[0054] The power support mode starting module 140 is used to control the power type energy storage device to enter the power support mode when it is determined that the microgrid is unplanned off-grid, and the power type energy storage device charges and discharges the microgrid in the power support mode.

[0055] The source-load power adjustment module 150 is used to adjust the source-load power of the microgrid when the power-type energy storage device is in the power support mode.

[0056] The power support mode exit module 160 is used to control the power type energy storage device to exit the power support mode after the microgrid reaches the source-load power balance.

[0057] According to the control device of the microgrid of the embodiment of the present application, a power type energy storage device is connected to the microgrid. When the power support mode startup module 140 determines that the microgrid is unplanned off-grid, the power type energy storage device is controlled to enter the power support mode, and the power type energy storage device can charge and discharge the microgrid in the power support mode. Due to the high charge and discharge rate of the power type energy storage device, at the moment of unplanned off-grid, the power type energy storage device releases or absorbs the unbalanced power in the microgrid, providing the microgrid with power support for seconds to minutes, so that the microgrid dispatching and control system can switch the working mode of the original energy storage system within a relatively sufficient time, flexibly adjust the power output and load demand in the microgrid, meet the power balance while reducing transient disturbances, thereby ensuring the safe and stable operation of the microgrid when off-grid. The above-mentioned adjustment method for responding to planned off-grid of the microgrid can achieve better control effect and control reliability while reducing the requirements for the response speed of the communication, control device and power electronic device in the microgrid control system.

[0058] The present application also provides a microgrid. FIG3 is a schematic diagram of the hardware structure of an embodiment of the microgrid of the present application. The microgrid includes a feeder network, a point of common connection (PCC), a power storage device 220, and a controller 230.

[0059] The feeder network is connected to power sources, loads, and non-power energy storage devices 213. A point of common connection (PCC) connects the feeder network to the public grid. Power energy storage devices 220 are connected to the feeder network. A controller 230 is connected to the feeder network, the PCC, and the power energy storage devices 220.

[0060] In some embodiments, power storage device 220 is connected between the point of common connection (PCC) and the feeder network. Because power storage device 220 is located near the PCC, communication latency is minimized, resulting in response times of less than 10ms, enabling seamless on-grid and off-grid switching.

[0061] The feeder network may include multiple feeders, such as feeder A, feeder B, and feeder C. Each feeder may be provided with a circuit breaker CB and a section circuit breaker SCB. The power source in the feeder network may be, for example, a distributed power source. Optionally, the power source in the feeder network may include at least one of a photovoltaic power generation system 211a, a micro gas turbine 211b, a wind power generation system 211c, or a diesel generator 211d. Each power source may be connected to the microgrid 200 via a local controller LC. The electrical load may include both critical and non-critical loads. The non-power storage device 213 may be, for example, an energy storage device.

[0062] The power energy storage device 220 is, for example, a supercapacitor, a flywheel energy storage device, etc.

[0063] Figure 4 is a schematic diagram of the hardware structure of a controller in one embodiment of a microgrid according to the present application. Controller 230 includes memory 231 and at least one processor 232. Memory 231 stores instructions, and at least one processor 232 invokes the instructions in memory 231, causing controller 230 to execute the microgrid control method according to any of the aforementioned embodiments of the present application.

[0064] A power-type energy storage device is connected to the microgrid, and the control method of the microgrid includes: when it is determined that the microgrid is unplanned off-grid, controlling the power-type energy storage device to enter the power support mode, and the power-type energy storage device charges and discharges the microgrid in the power support mode; while the power-type energy storage device is in the power support mode, adjusting the source-load power of the microgrid; after the microgrid reaches source-load power balance, controlling the power-type energy storage device to exit the power support mode.

[0065] Specifically, the processor 232 may include a central processing unit (CPU), or an application-specific integrated circuit (ASIC), or may be configured to implement one or more integrated circuits of the embodiments of the present application.

[0066] The memory 231 may include a large capacity memory 231 for data or instructions. By way of example and not limitation, the memory 231 may include a hard disk drive (HDD), a floppy disk drive, a flash memory, an optical disk, a magneto-optical disk, a magnetic tape, or a universal serial bus (USB) drive, or a combination of two or more of these. Where appropriate, the memory 231 may include a removable or non-removable (or fixed) medium. Where appropriate, the memory 231 may be inside or outside the integrated gateway disaster recovery device. In a specific embodiment, the memory 231 is a non-volatile solid-state memory. In a specific embodiment, the memory 231 includes a read-only memory (ROM). Where appropriate, the ROM may be a mask-programmed ROM, a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), an electrically rewritable ROM (EAROM), or a flash memory, or a combination of two or more of these.

[0067] In one example, the control device may further include a communication interface 233 and a bus 234. The processor 232, the memory 231, and the communication interface 233 are connected via the bus 234 and communicate with each other.

[0068] The communication interface 233 is mainly used to implement communication between various modules, devices, units and / or equipment in the embodiments of the present application.

[0069] Bus 234 includes hardware, software or both, and the parts of online data flow metering equipment are coupled together. For example, but not limitation, bus can include accelerated graphics port (AGP) or other graphics bus, enhanced industry standard architecture (EISA) bus, front side bus (FSB), hypertransport (HT) interconnection, industry standard architecture (ISA) bus, infinite bandwidth interconnection, low pin count (LPC) bus, memory 231 bus, micro channel architecture (MCA) bus, peripheral component interconnection (PCI) bus, PCI-Express (PCI-X) bus, serial advanced technology attachment (SATA) bus, video electronics standard association local (VLB) bus or other suitable bus or two or more of these combinations. In appropriate cases, bus 234 can include one or more buses. Although the present application embodiment describes and shows specific bus, the application considers any suitable bus or interconnection.

[0070] In addition, in conjunction with the microgrid control method in the above embodiments, the present application embodiment may provide a computer-readable storage medium for implementation. The computer-readable storage medium stores instructions that, when executed by a processor, implement any of the microgrid control methods in the above embodiments.

[0071] A power-type energy storage device is connected to the microgrid, and the control method of the microgrid includes: when it is determined that the microgrid is unplanned off-grid, controlling the power-type energy storage device to enter the power support mode, and the power-type energy storage device charges and discharges the microgrid in the power support mode; while the power-type energy storage device is in the power support mode, adjusting the source-load power of the microgrid; after the microgrid reaches source-load power balance, controlling the power-type energy storage device to exit the power support mode.

[0072] The present application is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, a detailed description of known methods is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present application is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications and additions, or change the order of the steps after understanding the spirit of the present application.

[0073] The functional blocks shown in the above block diagram can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of the present application are programs or code segments that are used to perform the required tasks. Programs or code segments can be stored in machine-readable media, or transmitted on a transmission medium or a communication link by a data signal carried in a carrier wave. "Machine-readable media" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROMs, flash memories, erasable ROMs (EROMs), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency (RF) links, etc. The code segments can be downloaded via computer networks such as the Internet, intranets, etc.

[0074] It should also be noted that the exemplary embodiments mentioned in this application describe some methods or systems based on a series of steps or devices. However, this application is not limited to the order of the above steps. In other words, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0075] The above description is only a specific embodiment of the present application. Those skilled in the art will clearly understand that for the convenience and brevity of description, the specific working processes of the systems, modules and units described above can refer to the corresponding processes in the aforementioned method embodiments, and will not be repeated here. It should be understood that the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the scope of protection of the present application.

Claims

1. A control method for a microgrid, characterized in that, A power-type energy storage device is connected within the microgrid, and the control method of the microgrid includes: When it is determined that the microgrid is in an unplanned islanding state, controlling the power-type energy storage device to enter the power support mode, and the power-type energy storage device charges and discharges the microgrid in the power support mode; During the period when the power-type energy storage device is in the power support mode, adjusting the source-load power of the microgrid; After the microgrid reaches source-load power balance, controlling the power-type energy storage device to exit the power support mode.

2. The control method of the microgrid according to claim 1, characterized in that, Before the step of determining that the microgrid is in an unplanned islanding state, the control method of the microgrid further includes: Generating islanding information of the microgrid based on the disconnection of the switch at the point of common coupling of the microgrid; Based on the islanding information, determining whether the microgrid is in a planned islanding state; When it is determined that the microgrid is in a planned islanding state, maintaining the current operating state of the microgrid.

3. The control method of the microgrid according to claim 1, characterized in that The maximum output or absorption power of the power-type energy storage device is greater than the maximum power deficit generated by the microgrid within a source-load power adjustment cycle.

4. The control method of the microgrid according to claim 1, characterized in that The microgrid includes a point of common coupling for connecting to the public grid and a feeder network connected to the point of common coupling. A power source, an electrical load, and a non-power-type energy storage device are connected in the feeder network. Among them, the power-type energy storage device is connected between the point of common coupling and the feeder network.

5. The control method of the microgrid according to claim 4, characterized in that During the period when the power-type energy storage device is in the power support mode, adjusting the source-load power of the microgrid includes: Real-time detecting and obtaining the power imbalance of the microgrid, and the power imbalance is equal to the real-time output power of the power source in the feeder network plus the real-time discharge power of the non-power-type energy storage device minus the real-time load rate of the electrical load and minus the real-time charging power of the non-power-type energy storage device; Adjusting the real-time charge-discharge power of the power-type energy storage device according to the power imbalance; Adjusting the source-load power of the microgrid according to the power imbalance.

6. The control method of the microgrid according to claim 5, characterized in that, The adjusting the real-time charge-discharge power of the power-type energy storage device according to the power imbalance includes: Controlling the real-time charge-discharge power of the power-type energy storage device to be equal to the power imbalance.

7. The control method of the microgrid according to claim 5, characterized in that, The adjusting the source-load power of the microgrid according to the power imbalance includes: When the power imbalance is positive, controlling to reduce the output power of the power source in the feeder network and controlling to reduce the discharge power of the non-power-type energy storage device in the feeder network until the power imbalance is zero.

8. The control method of the microgrid according to claim 5, characterized in that, The adjusting the source-load power of the microgrid according to the power imbalance includes: When the power imbalance is negative, performing source-load power adjustment in the following order until the power imbalance is zero: Controlling to increase the output power of the power source in the feeder network; Controlling to reduce the charging power of the non-power-type energy storage device in the feeder network and controlling to increase the discharge power of the non-power-type energy storage device in the feeder network; Controlling to reduce the controllable load amount of the electrical load in the feeder network and disconnecting the non-essential load in the electrical load.

9. A control device for a microgrid, characterized in that, A power-type energy storage device is connected within the microgrid, and the control device of the microgrid includes: A power support mode startup module, configured to control the power-type energy storage device to enter a power support mode when it is determined that the microgrid is unplanned islanding. The power-type energy storage device charges and discharges the microgrid in the power support mode; A source-load power adjustment module, configured to adjust the source-load power of the microgrid during the period when the power-type energy storage device is in the power support mode; A power support mode exit module, configured to control the power-type energy storage device to exit the power support mode after the microgrid reaches source-load power balance.

10. A microgrid, characterized in that, including: A feeder network, in which a power source, an electrical load, and a non-power-type energy storage device are connected; A point of common coupling, configured to connect the feeder network to the public grid; A power-type energy storage device, connected to the feeder network; A controller, connected to the feeder network, the point of common coupling, and the power-type energy storage device. The controller includes a memory and at least one processor, and instructions are stored in the memory. The at least one processor invokes the instructions in the memory, so that the controller executes the control method of the microgrid according to any one of claims 1 to 8.

11. A computer-readable storage medium, on which instructions are stored, characterized in that, When the instructions are executed by the processor, the control method of the microgrid according to any one of claims 1 to 8 is implemented.

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