Microgrid system, control method based on microgrid system, v2g controller, computer-readable storage medium, and computer instruction product

Abstract

A microgrid system, a control method based on the microgrid system, a vehicle to grid (V2G) controller, a computer-readable storage medium, and a computer instruction product. The microgrid system comprises a V2G controller, a substation, at least one V2G charging pile, and at least one electrical device. The substation is connected to the V2G charging pile and the electrical device by means of an alternating current bus of a sub-grid. When the microgrid system is in a V2G mode, the V2G controller acquires the power demand of the sub-grid and locally available energy storage of the sub-grid. The V2G controller assigns a discharge task to each discharge-capable vehicle on the basis of the power demand and the locally available energy storage, allowing each discharge-capable vehicle to discharge to the alternating current bus of the sub-grid on the basis of the assigned discharge task.

Description

Micro-grid system, control method based on micro-grid system, V2G controller, computer readable storage medium and computer instruction product

[0001] The present application claims priority to the Chinese patent application No. 2024108422185, filed on June 26, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the technical field of vehicles, in particular to a micro-grid system, a control method based on the micro-grid system, a V2G controller, a computer readable storage medium and a computer instruction product. BACKGROUND

[0003] Currently, the vehicle to grid (V2G) technology is still in the exploratory stage. In theory, when the electricity demand is at its peak, the V2G technology can be used to reduce the load of power plants by using vehicle energy storage. Currently, vehicles transmit power to the large power grid, which then distributes power to the power-consuming devices of the sub-grid. However, too many and unstable power sources connected to the grid will also bring a lot of impact to the grid, thereby increasing the operating cost of the grid. TECHNICAL PROBLEM

[0004] The purpose of the present application is to provide a micro-grid system, a control method based on the micro-grid system, a V2G controller, a computer readable storage medium and a computer instruction product to improve the problem of high operating cost of the existing power grid. TECHNICAL SOLUTION

[0005] The first aspect of the embodiments of the present application provides a micro-grid system, comprising: a vehicle to grid (V2G) controller, a substation, at least one V2G charging pile and at least one power-consuming end device; the substation is connected to the V2G charging pile and the power-consuming end device through an alternating current bus of a sub-grid;

[0006] In the case that the micro-grid system is in a V2G mode, the V2G controller obtains a power demand of the sub-grid and a local available energy storage of the sub-grid, the local available energy storage of the sub-grid includes a sum of dischargeable amounts of each dischargeable vehicle connected to the at least one V2G charging pile, and the power demand of the sub-grid includes a power demand of the at least one power-consuming end device; the V2G controller allocates a discharge task for each of the dischargeable vehicles according to the power demand and the local available energy storage, so that each of the dischargeable vehicles discharges to the alternating current bus of the sub-grid based on the allocated discharge task.

[0007] The second aspect of the embodiments of the present application provides a control method based on the micro-grid system, comprising:

[0008] In a case where the micro-grid system is in a V2G mode, a V2G controller acquires power consumption demand of a sub-grid and local available energy storage of the sub-grid, the local available energy storage of the sub-grid including a sum of dischargeable amounts of each dischargeable vehicle accessing at least one V2G charging post, and the power consumption demand of the sub-grid including power consumption demand of at least one power consumption terminal device;

[0009] The V2G controller allocates a discharge task for each of the dischargeable vehicles according to the power consumption demand and the local available energy storage, so that each of the dischargeable vehicles is used to discharge to an AC bus of the sub-grid based on the allocated discharge task.

[0010] A third aspect of the embodiments of the present application provides a V2G controller, comprising a processor and a memory, the memory being configured to store computer instructions, and the processor being configured to invoke the computer instructions to execute the step instructions as in the second aspect of the embodiments of the present application.

[0011] A fourth aspect of the embodiments of the present application provides a computer readable storage medium, wherein the computer readable storage medium stores computer instructions, and the computer instructions, when executed by a processor, cause the processor to perform part or all of the steps described in the second aspect of the embodiments of the present application.

[0012] A fifth aspect of the embodiments of the present application provides a computer instruction product, wherein the computer instruction product comprises computer instructions, and the computer instructions are operable to cause a computer to perform part or all of the steps described in the second aspect of the embodiments of the present application. The computer instruction product can be a software installation package.

[0013] In the embodiment of the present application, the micro-grid system comprises a vehicle-to-grid (V2G) controller, a transformer substation, at least one V2G charging pile, and at least one power consumption terminal device; the transformer substation is connected to the V2G charging pile and the power consumption terminal device through an alternating current bus of a sub-grid; in the case that the micro-grid system is in a V2G mode, the V2G controller acquires power consumption demand of the sub-grid and local available energy storage of the sub-grid, the local available energy storage of the sub-grid comprises a sum of dischargeable amounts of each dischargeable vehicle connected to the at least one V2G charging pile, and the power consumption demand of the sub-grid comprises power consumption demand of the at least one power consumption terminal device; the V2G controller allocates a discharge task for each dischargeable vehicle according to the power consumption demand and the local available energy storage, so that each dischargeable vehicle discharges to the alternating current bus of the sub-grid based on the allocated discharge task. In the embodiment of the present application, when the micro-grid system is in the V2G mode, the dischargeable vehicle in the micro-grid system discharges to the alternating current bus of the sub-grid, and the discharge of the dischargeable vehicle to the alternating current bus of the sub-grid can directly bear the power consumption demand of the sub-grid. Compared with the discharge of the dischargeable vehicle to the upper-level power grid, on the one hand, the impact of the discharge of the dischargeable vehicle to the upper-level power grid on the upper-level power grid can be avoided, and on the other hand, the number of energy conversion can be reduced, thereby reducing the operation cost of the power grid. BRIEF DESCRIPTION OF DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0015] FIG. 1 is a structural schematic diagram of a micro-grid system according to an embodiment of the present application;

[0016] FIG. 2 is a structural schematic diagram of another micro-grid system according to an embodiment of the present application;

[0017] FIG. 3 is a power grid system architecture diagram of a plurality of micro-grid systems in a power grid according to an embodiment of the present application;

[0018] FIG. 4 is an energy flow schematic diagram of a micro-grid system in a load mode according to an embodiment of the present application;

[0019] FIG. 5 is an energy flow schematic diagram of a micro-grid system in a V2G mode and local available energy storage of a sub-grid being greater than power consumption demand of the sub-grid according to an embodiment of the present application;

[0020] FIG. 6 is an energy flow schematic diagram of a micro-grid system in a V2G mode and local available energy storage of a sub-grid being less than or equal to power consumption demand of the sub-grid according to an embodiment of the present application;

[0021] Fig. 7 is a schematic diagram of energy flow of the present scheme and the conventional V2G technology according to an embodiment of the present application;

[0022] Fig. 8 is a flowchart of a control method of a micro-grid system according to an embodiment of the present application;

[0023] Fig. 9 is a schematic diagram of a V2G controller according to an embodiment of the present application.

[0024] The reference signs are explained as follows: 100, micro-grid system; 10, V2G controller; 20, transformer substation; 30, V2G charging pile; 40, power consumption terminal device; 50, AC bus of sub-grid; 60, power transmission line of upper grid; 70, energy storage device; 80, green power generation device; 90, one-way DC charging pile; 01, V2G parking space; 02, charging parking space; 301, V2G AC charging pile; 302, V2G DC charging pile; 901, processor; 902, memory; 903, communication bus. Embodiments of the present application

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0026] The terms "first", "second", and the like in the specification and claims of the present application and the above drawings are used to distinguish different objects, and are not used to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but can optionally include other steps or units not listed or can optionally include other steps or units inherent to the process, method, product or device.

[0027] In the present application, "embodiment" means that the specific features, structures or characteristics described in connection with the embodiment can be included in at least one embodiment of the present application. The phrase appears at various places in the specification does not necessarily refer to the same embodiment, nor is it mutually exclusive or alternative to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in the present application can be combined with other embodiments.

[0028] Vehicle to grid (V2G) technology is a technology for electric vehicles to supply power to the grid. With the rapid growth of new energy vehicle sales, the global power battery installation capacity for loading vehicles has reached hundreds of billions of watt-hours (GWh) per year, and these vehicles will be the best mobile energy storage equipment in the future. With the help of V2G technology, cities can manage the entire city's power state by inviting vehicles to participate in charging and discharging, thereby reducing power loss and generation cost.

[0029] Please refer to FIG. 1, which is a structural schematic diagram of a micro-grid system 100 provided by an embodiment of the present application. As shown in FIG. 1, the micro-grid system 100 includes a vehicle to grid (V2G) controller 10, a transformer station 20, at least one V2G charging pile 30 (as shown in the dashed box in FIG. 1), and at least one power-consuming end device 40. FIG. 1 takes one V2G charging pile 30 and one power-consuming end device 40 as an example; the transformer station 20 connects the V2G charging pile 30 and the power-consuming end device 40 through an AC bus 50 of a sub-grid;

[0030] In a case where the micro-grid system 100 is in a V2G mode, the V2G controller 10 acquires a power consumption demand of the sub-grid and a locally available energy storage of the sub-grid, the locally available energy storage of the sub-grid including a sum of dischargeable amounts of each dischargeable vehicle accessing the at least one V2G charging pile 30, and the power consumption demand of the sub-grid including a power consumption demand of the at least one power-consuming end device 40; the V2G controller 10 allocates a discharge task for each dischargeable vehicle according to the power consumption demand and the locally available energy storage of the sub-grid, so that each dischargeable vehicle discharges to the AC bus 50 of the sub-grid based on the allocated discharge task.

[0031] A vehicle to grid (V2G) controller is configured to, in a case where a micro-grid system 100 is in a V2G mode, allocate a discharge task for each dischargeable vehicle accessing at least one V2G charging pile 30 according to a power consumption demand of a sub-grid and a locally available energy storage of the sub-grid. Each dischargeable vehicle discharges to an AC bus 50 of the sub-grid based on the allocated discharge task.

[0032] The AC bus 50 of the sub-grid can be a 220V / 380V AC bus.

[0033] The V2G charging pile 30 can include at least one of a V2G AC charging pile 301 and a V2G DC charging pile 302. The V2G AC charging pile 301 can also be referred to as a V2G slow-charging AC pile. The V2G DC charging pile 302 can also be referred to as a V2G fast-charging DC pile.

[0034] Each V2G charging pile 30 can be connected with at least one V2G parking space 01.

[0035] In the embodiment of the present application, when the micro-grid system 100 is in the V2G mode, the dischargeable vehicles in the micro-grid system 100 discharge to the AC bus 50 of the sub-grid. The discharge of the dischargeable vehicles to the AC bus 50 of the sub-grid can directly bear the power demand of the sub-grid. Compared with the discharge of the dischargeable vehicles to the upper-level grid, on the one hand, the impact of the discharge of the dischargeable vehicles to the upper-level grid on the upper-level grid can be avoided, and on the other hand, the number of energy conversion can be reduced, thereby reducing the operation cost of the grid.

[0036] Please refer to FIG. 2, which is a structural schematic diagram of another micro-grid system 100 provided by the embodiment of the present application. As shown in FIG. 2, on the basis of FIG. 1, the micro-grid system 100 further includes a power transmission line 60 of an upper-level grid, which is connected with the transformer station 20 through the V2G controller 10. The transformer station 20 is the transformer station 20 corresponding to the sub-grid. The upper-level grid is the upper-level grid of the sub-grid.

[0037] In the embodiment of the present application, the upper-level grid is added. On the one hand, the V2G controller 10 can send a power-on request to the upper-level grid, and request the upper-level grid to send power to the sub-grid. On the other hand, the V2G controller 10 can also control the local available energy storage of the sub-grid to send power to the upper-level grid.

[0038] The micro-grid system 100 can be in the V2G mode or the load mode or the emergency mode.

[0039] The micro-grid system 100 can select which mode to be in according to the load state of the upper-level grid.

[0040] The load state of the upper-level grid includes a high load state (which can correspond to a peak period of the upper-level grid), a medium load state (which can correspond to a flat period of the upper-level grid), a low load state (which can correspond to a valley period of the upper-level grid), and a fault state. When the load state of the upper-level grid is the high load state, the load of the upper-level grid is large. When the load state of the upper-level grid is the low load state, the load of the upper-level grid is small. When the load state of the upper-level grid is the fault state, the upper-level grid cannot supply power to the sub-grid.

[0041] When the load state of the upper-level grid is the high load state, the micro-grid system 100 can be controlled to be in the V2G mode.

[0042] When the load state of the upper-level grid is the low load state, the micro-grid system 100 can be controlled to be in the load mode.

[0043] When the load state of the upper grid is a medium load state, the micro-grid system 100 can be controlled to be in a V2G mode or a load mode.

[0044] When the load state of the upper grid is a fault state, the micro-grid system 100 can be controlled to be in an emergency mode.

[0045] When the micro-grid system 100 is in the V2G mode, the locally available energy storage of the sub-grid can directly discharge to the AC bus 50 of the sub-grid. At this time, the V2G controller 10 can open a power-on request to the upper grid, requesting the upper grid to send power to the sub-grid. The V2G controller 10 can also control the locally available energy storage of the sub-grid to send power to the upper grid.

[0046] Optionally, when the locally available energy storage of the sub-grid is greater than the power-on demand, the V2G controller 10 determines whether the upper grid needs reverse power transmission according to the load state of the upper grid.

[0047] When the upper grid needs reverse power transmission, the V2G controller 10 controls each of the dischargeable vehicles to input the excess discharge amount to the transformer station 20 through the AC bus 50 of the sub-grid, and then to the transmission line 60 of the upper grid; the excess discharge amount is less than or equal to a first difference, and the first difference is the difference between the sum of the dischargeable amounts and the power-on demand of the sub-grid.

[0048] The first difference can be set after the V2G controller 10 obtains the power-on demand of the sub-grid and the locally available energy storage of the sub-grid. The first difference can be stored in the memory (such as a non-volatile memory) of the V2G controller 10.

[0049] In the embodiment of the application, when the upper grid needs reverse power transmission, the excess discharge amount can be uploaded to the upper grid when the locally available energy storage is greater than the power-on demand, thereby realizing the reverse power transmission function of the sub-grid to the upper grid and meeting the power-on demand of the upper grid.

[0050] Optionally, when the locally available energy storage of the sub-grid is less than or equal to the power-on demand, the V2G controller 10 opens a power-on request to the upper grid and closes the reverse power transmission function of the sub-grid to the upper grid.

[0051] For example, when the local available energy storage of the sub-grid is greater than the power demand of the sub-grid, if the load state of the upper grid is a high load state, the V2G controller 10 controls the local available energy storage of the sub-grid to send power to the upper grid. When the local available energy storage of the sub-grid is less than or equal to the power demand of the sub-grid, if the load state of the upper grid is a medium load state, the V2G controller 10 opens a power request to the upper grid, requesting the upper grid to send power to the sub-grid.

[0052] When the V2G controller 10 opens a power request to the upper grid, the upper grid can send power to the sub-grid. When the reverse power sending function of the sub-grid to the upper grid is closed, the sub-grid cannot send power to the upper grid. When the upper grid needs reverse power sending, the sub-grid can send power to the upper grid.

[0053] In the embodiment of the application, when the local available energy storage is less than the power demand, a power request can be opened to the upper grid to meet the power demand of the sub-grid, and the reverse power sending function of the sub-grid to the upper grid is closed, so as to avoid the simultaneous occurrence of reverse power sending of the sub-grid to the upper grid and power sending of the upper grid to the sub-grid, thereby improving energy utilization efficiency.

[0054] Optionally, when the micro-grid system 100 is in a load mode, the V2G controller 10 enters a sleep state, and the power of all power-consuming devices in the sub-grid is sourced from the upper grid.

[0055] When the micro-grid system 100 is in a load mode, the power transmission line 60 of the upper grid can discharge through the transformer station 20 to the AC bus 50 of the sub-grid, and the power of all power-consuming devices in the sub-grid is sourced from the upper grid. At this time, the V2G controller 10 does not need to refer to the power dispatching, and the V2G controller 10 enters a sleep state, which can reduce the power consumption of the V2G controller 10. The power transmission line 60 of the upper grid can send power to at least one V2G charging pile 30 and at least one power-consuming terminal device 40 of the sub-grid through the transformer station 20.

[0056] Optionally, when the micro-grid system 100 is in an emergency mode, the V2G controller 10 acquires the power demand of the sub-grid and the local available energy storage of the sub-grid, and preferentially supplies power to power-consuming devices with high priority in the sub-grid.

[0057] When the micro-grid system 100 is in an emergency mode, the local available energy storage of the sub-grid can directly discharge to the AC bus 50 of the sub-grid. At this time, since the upper grid is in a fault state, the V2G controller 10 cannot open a power request to the upper grid, and cannot request the upper grid to send power to the sub-grid.

[0058] The at least one electrical end device 40 can include a high-priority electrical device and a low-priority electrical device.

[0059] When the micro-grid system 100 is in the emergency mode, the locally available energy storage of the sub-grid can be used to supply power to the high-priority electrical device of the sub-grid first, and the electrical energy is supplied to the high-priority electrical device first, thereby improving the reliability of the electrical device of the high-priority device in the emergency mode. For example, the high-priority electrical device can include a hospital electrical device, a communication or emergency lighting lamp. The low-priority electrical device can include a residential lighting electrical device.

[0060] In the embodiment of the present application, when the micro-grid system 100 is in the V2G mode, the dischargeable vehicle in the micro-grid system 100 discharges to the AC bus 50 of the sub-grid, and the dischargeable vehicle can directly bear the electrical demand of the sub-grid. Compared with the discharge of the dischargeable vehicle to the upper-level grid, on the one hand, the impact of the discharge of the dischargeable vehicle to the upper-level grid can be avoided, and on the other hand, the number of energy conversion can be reduced, thereby reducing the operation cost of the grid.

[0061] Optionally, the discharge task includes a discharge period and a discharge power; and each of the dischargeable vehicles discharges to the AC bus 50 of the sub-grid based on the assigned discharge task, including:

[0062] Each of the dischargeable vehicles discharges to the AC bus 50 of the sub-grid according to the assigned discharge power in the assigned discharge period, and the sum of the cumulative discharge amounts of each of the dischargeable vehicles in the assigned discharge period is less than or equal to the electrical demand.

[0063] In the embodiment of the present application, the V2G controller 10 can assign a discharge task to each of the dischargeable vehicles accessing the at least one V2G charging pile 30 according to the electrical demand of the sub-grid and the locally available energy storage of the sub-grid. The V2G controller 10 can establish a communication connection (such as a wired communication connection or a wireless communication connection) with each of the dischargeable vehicles accessing the at least one V2G charging pile 30.

[0064] Each of the dischargeable vehicles discharges to the AC bus 50 of the sub-grid according to the assigned discharge power in the assigned discharge period. Each of the dischargeable vehicles can be allowed to discharge according to a fixed discharge period and a fixed discharge power, and each of the dischargeable vehicles can be allowed to stably discharge to the AC bus 50 of the sub-grid, thereby ensuring the stability of the power supply of the sub-grid in the V2G mode.

[0065] Optionally, the at least one V2G charging pile 30 and the AC bus 50 of the sub-grid use the same voltage standard.

[0066] The at least one V2G charging pile 30 and the AC bus 50 of the sub-grid use the same voltage standard. When the micro-grid system 100 is in the V2G mode, the V2G charging pile 30 discharges to the AC bus 50 of the sub-grid without voltage conversion, which can improve the energy conversion efficiency.

[0067] Optionally, as shown in FIG. 2, the micro-grid system 100 can further include an energy storage device 70, at least one green power generation device 80, and at least one one-way DC charging pile 90. The at least one green power generation device 80 is connected to the input end of the energy storage device 70. The substation 20 is connected to the energy storage device 70, the at least one green power generation device 80, and the at least one one-way DC charging pile 90 through the sub-grid AC bus. The at least one one-way DC charging pile 90 is connected to at least one charging parking space 02 (such as the ordinary charging parking space shown in FIG. 2). The local available energy storage of the sub-grid further includes the available energy storage of the energy storage device 70. The power demand of the sub-grid further includes the power demand of the at least one one-way DC charging pile 90.

[0068] In the embodiments of the present application, the energy storage device 70 and each dischargeable vehicle connected to the at least one V2G charging pile 30 are local energy storage devices 70 of the sub-grid. The local available energy storage of the sub-grid includes the sum of the dischargeable energy of each dischargeable vehicle connected to the at least one V2G charging pile 30 plus the available energy storage of the energy storage device 70.

[0069] The dischargeable energy of each dischargeable vehicle connected to the at least one V2G charging pile 30 can be set by the user of each dischargeable vehicle. The available energy storage of the energy storage device 70 can be set by the operator of the micro-grid system 100. For example, the dischargeable energy of the dischargeable vehicle can be set as a corresponding proportion of the total energy of the dischargeable vehicle (for example, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, etc. of the total energy of the dischargeable vehicle). The available energy storage of the energy storage device 70 can be set as a corresponding proportion of the total energy of the energy storage device 70 (for example, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, etc. of the total energy of the energy storage device 70). It should be noted that the dischargeable energy of any two dischargeable vehicles can be set to be the same or different.

[0070] The one-way direct-current charging pile 90 is different from the V2G charging pile 30 in that the AC bus 50 of the sub-power grid can charge the vehicle accessing the one-way direct-current charging pile 90 through the one-way direct-current charging pile 90, and the vehicle accessing the one-way direct-current charging pile 90 cannot discharge the AC bus of the sub-power grid through the one-way direct-current charging pile 90. The AC bus 50 of the sub-power grid can charge the vehicle accessing the V2G charging pile 30 through the V2G charging pile 30, and the vehicle accessing the V2G charging pile 30 can also discharge the AC bus of the sub-power grid through the V2G charging pile 30.

[0071] Optionally, as shown in FIG. 2, the at least one V2G charging pile 30 (FIG. 2 takes one V2G charging pile 30 as an example) includes at least one V2G AC charging pile 301 (FIG. 2 takes one V2G AC charging pile 301 as an example) and / or at least one V2G direct-current charging pile 302 (FIG. 2 takes one V2G direct-current charging pile 302 as an example); the at least one V2G AC charging pile 301 is respectively connected to at least one V2G parking space 01, and the at least one V2G direct-current charging pile 302 is respectively connected to at least one V2G parking space 01.

[0072] The at least one first output end of the energy storage device 70 is respectively connected to the input end of the at least one V2G direct-current charging pile 302, and the at least one second output end of the energy storage device 70 is respectively connected to the input end of the at least one one-way direct-current charging pile 90.

[0073] In the embodiment of the application, one V2G charging pile 30 can include one V2G AC charging pile 301 or one V2G direct-current charging pile 302, or one V2G charging pile 30 can include one V2G AC charging pile 301 and one V2G direct-current charging pile 302.

[0074] When one V2G charging pile 30 includes one V2G AC charging pile 301 and one V2G direct-current charging pile 302, one V2G AC charging pile 301 and one V2G direct-current charging pile 302 can be connected to the same V2G parking space 01 (as shown in FIG. 2), or can be respectively connected to two different V2G parking spaces 01.

[0075] The V2G parking space 01 is a parking space supporting the V2G technology, and the vehicle parked in the V2G parking space 01 can be charged and discharged to the sub-power grid or the upper-level power grid. The ordinary charging parking space 02 is a parking space not supporting the V2G technology, and the vehicle parked in the V2G parking space 01 can be charged, but cannot be discharged to the sub-power grid or the upper-level power grid.

[0076] The energy storage device 70 can connect the input end of the V2G DC charging pile 302 through the first output end. When the AC bus 50 of the sub-power grid cannot charge the vehicle connected to the V2G DC charging pile 302, the energy storage device 70 can charge the vehicle connected to the V2G DC charging pile 302 through the V2G DC charging pile 302.

[0077] The energy storage device 70 can connect the input end of the one-way DC charging pile 90 through the second output end. When the AC bus 50 of the sub-power grid cannot charge the vehicle connected to the one-way DC charging pile 90, the energy storage device 70 can charge the vehicle connected to the one-way DC charging pile 90 through the one-way DC charging pile 90.

[0078] The energy storage device 70 can directly supply power to the V2G DC charging pile 302 and the one-way DC charging pile 90. The energy storage device 70 does not need to upload the power to the sub-power grid, and then the sub-power grid distributes the power to the V2G DC charging pile 302 and the one-way DC charging pile 90, thereby improving the energy conversion efficiency.

[0079] Optionally, the voltage (DC voltage) output by the first output end of the energy storage device 70 is the same as the DC voltage output by the V2G DC charging pile 302, and the voltage (DC voltage) output by the second output end of the energy storage device 70 is the same as the DC voltage output by the one-way DC charging pile 90. The energy storage device 70 charges the vehicle connected to the V2G DC charging pile 302 through the V2G DC charging pile 302, without the need for DC voltage conversion, thereby improving the energy conversion efficiency.

[0080] The micro-power grid system 100 can reduce the loss in the V2G discharging process, and as much as possible, the energy released by the vehicle is consumed locally to improve the overall working efficiency and reduce the working loss.

[0081] Please refer to FIG. 3, which is a large-power grid system architecture diagram of a plurality of micro-power grid systems 100 in a large-power grid according to an embodiment of the present application. As shown in FIG. 3, the large-power grid is a higher-level power grid than the sub-power grid (for example, the large-power grid can be the upper-level power grid in FIG. 2). The large-power grid can be the upper-level power grid or the upper N-level power grid of the sub-power grid. The power transmission line of the large-power grid can be the power transmission line 60 of the upper-level power grid in FIG. 2.

[0082] The large power grid system shown in FIG. 3 divides the discrete electric vehicles and V2G input sources in a region into several micro-grid systems 100. For example, several sub-micro-grid systems are divided by V2G suppliers. The division can be based on the lowest cost, the highest benefit, etc. As long as there is a parking lot, a sub-micro-grid system can be divided. The division is planned according to the surrounding power consumption, the number of parking spaces, and the power grid architecture. The dashed box shown in FIG. 3 is one of the micro-grid systems 100. Each micro-grid system 100 is controlled by a V2G controller 10 (e.g., the white box with lightning shown in FIG. 3). The V2G controller 10 uniformly controls the internal discharge process of the micro-grid system 100, and maximizes the consumption of vehicle energy by task management to provide power for surrounding power consumption equipment and users. By optimizing power distribution, the number of uploads to the large power grid is reduced, and the power loss generated during uploading is also reduced. Consuming power locally can also reduce energy loss when uploading to the large power grid. One V2G controller 10 corresponds to one transformer station 20 and the equipment directly connected to the transformer station 20. The V2G controller 10 manages all V2G devices directly connected thereto (e.g., assigns tasks to V2G devices and controls the state). Among them, the power end user can connect to other subordinate transformer stations 20. The next level transformer station 20 can be connected to another V2G controller 10. One V2G controller 10 corresponds to one sub-grid.

[0083] The implementation of the V2G technology will face a problem. When a large number of vehicles start discharging and uploading to the large power grid, it will generate a large impact on the power grid, which is not conducive to reducing the operation cost of the power grid. The large power grid system divides the discrete vehicles into micro-grid systems 100, and then uploads through the micro-grid system 100 and the large power grid when the local power demand is met. This will greatly reduce the number and frequency of uploading to the large power grid. The micro-grid system 100 can realize the use of the V2G technology while not significantly increasing the operation cost of the power grid.

[0084] In each micro-grid system 100, the V2G controller 10 controls the running state of the micro-grid system 100. The micro-grid system 100 is based on the original circuit for modification, and the V2G controller 10 is added to the transformer station 20 of the sub-grid for managing the working state of the entire micro-grid system 100. Each micro-grid system 100 includes one V2G controller 10 (e.g., the white box with lightning shown in FIG. 3) and one transformer station 20 (e.g., the gray box shown in FIG. 3). The V2G controller 10 is used to realize the V2G function of the sub-grid, and the transformer station 20 is used to realize the discharging function from the large power grid to the sub-grid.

[0085] When the micro-grid system 100 is in idle time without V2G demand, the overall and traditional power grid is used without difference, and the sub-grid normally inputs power for users through the large power grid; when the power grid (including the sub-grid and the large power grid) and the V2G operator start the V2G service demand, the discharging is distributed to each specific vehicle through the task allocation mechanism in the V2G controller 10, effectively reducing the energy waste caused by disordered discharging and multiple conversions. The V2G operator can set the condition for starting the V2G service demand in the V2G controller 10, and when the condition for starting the V2G service demand is met, the micro-grid system 100 is in the V2G mode, allowing the vehicle accessing the V2G charging pile 30 to discharge to the AC bus 50 of the sub-grid.

[0086] Under the architecture of the micro-grid system 100, the transformer in the transformer substation 20 does not need to be modified, and the modification and construction cost of the added V2G function can be reduced as much as possible, and the vehicle is precisely discharged in the specified sub-grid. Both the V2G function and the waste of construction resources and operation resources are reduced.

[0087] When the micro-grid system 100 opens the V2G function, the micro-grid system 100 reads the power demand of the sub-grid and the discharging capacity of the vehicle accessing the V2G charging pile 30 in real time, and allocates tasks for each vehicle accessing the V2G charging pile 30 in combination with the power demand of the V2G operator and the sub-grid. The vehicle undertakes the sub-grid power demand within the time period based on the task allocation; in addition, when the local sub-grid meets the V2G demand of the upper grid, the transformer of the transformer substation 20 of the sub-grid is uniformly output to the upper grid, ensuring that the energy released by each vehicle can be transported to the area that needs power. After the task allocation mechanism is equipped, the micro-grid system 100 will not require more power demand from the vehicle except for a part of redundancy, and the reduction of the subsequent vehicle experience of the user is minimized.

[0088] The V2G equipment (including: V2G DC charging pile 302, V2G AC charging pile 301, V2G parking space 01) matched with the micro-grid system 100 all use the same power voltage standard of the bus of the sub-grid. For example, they are all 220V or 380V. If the three-phase power (L1, L2, L3) of the sub-grid connected to the V2G equipment (such as the V2G DC charging pile 302) is 380V. If the live wire (L1 or L2 or L3) and the neutral wire N of the sub-grid connected to the V2G equipment (such as the V2G AC charging pile 301) are 220V.

[0089] When the micro-grid system 100 is in the load mode, the V2G device can directly obtain energy from the AC bus 50 of the sub-grid without conversion, and when the micro-grid system 100 is in the V2G mode, the energy output by the V2G device can be directly consumed by the power consumption load in the sub-grid without conversion, thereby reducing the loss caused by the transmission of the energy to the power consumption device in the sub-grid.

[0090] The V2G devices (including the V2G DC charging pile 302, the V2G AC charging pile 301, and the V2G parking space 01) of the micro-grid system 100 are uniformly used in the same power consumption voltage standard of the bus of the sub-grid. When the upper grid fails or is under maintenance, the lower sub-grid can start the emergency mode and request the vehicles in the sub-grid to participate in the V2G discharging task, so as to ensure the normal power consumption of the sub-grid in the case of failure.

[0091] When the micro-grid system 100 starts to work, the micro-grid system 100 determines the working mode via the V2G controller 10, and the working mode can include the load mode, the V2G mode, and the emergency mode.

[0092] Please refer to FIG. 4, which is an energy flow diagram of the micro-grid system 100 in the load mode. FIG. 4 is the energy flow diagram of the micro-grid system 100 based on FIG. 2. When the micro-grid system 100 is idle and has no V2G demand, the working mode of the micro-grid system 100 is the load mode. At this time, the V2G controller 10 is in the sleep state, and the power energy input from the upper grid (for example, the large grid) is the same as the operation mode of the sub-grid before the transformation. The power transmission line 60 of the upper grid supplies power to the power consumption devices (for example, the V2G AC charging pile 301, the V2G DC charging pile 302, the energy storage device 70, the unidirectional DC charging pile 90, and the power consumption terminal device 40) of the sub-grid via the V2G controller 10 and the transformer station 20. The V2G controller 10 waits to receive the V2G signal or the emergency control signal, at this time, all the devices in the sub-grid are operated in the energy storage or power consumption mode, and all the power sources of the sub-grid are the upper grid.

[0093] When the V2G control request is received by the V2G controller 10 of the micro-grid system 100, the working mode is switched from the load mode to the V2G mode, at this time, the V2G controller 10 of the micro-grid system 100 starts to count the internal power consumption demand, the number of vehicles, the discharging capacity, and the available V2G power of the sub-grid, and plans the discharging in the sub-grid at this time.

[0094] Please refer to FIG. 5, which is an energy flow diagram of a micro-grid system 100 in a V2G mode and local available energy storage of a sub-grid is greater than the power demand of the sub-grid. FIG. 5 is an energy flow diagram of the micro-grid system 100 based on FIG. 2, if the V2G discharge amount of the vehicles in the sub-grid is greater than the power demand. The V2G controller 10 opens the reverse power supply function, which is uploaded to the upper grid by the sub-grid input substation 20, and the vehicle discharge is preferentially merged into the AC bus 50 of the sub-grid instead of being directly uploaded to the upper grid, which can reduce the impact on the upper grid (for example, the large grid) when a large number of new energy vehicles are discharged, and also reduce the waste of the power end equipment 40 uploaded via the upper grid to the sub-grid. In FIG. 5, the V2G AC charging pile 301, the V2G DC charging pile 302 and the energy storage device 70 can supply power to the unidirectional DC charging pile 90 and the power end equipment 40, and the remaining part of the local available energy storage of the sub-grid after meeting the power demand of the sub-grid can be uploaded to the upper grid by the V2G AC charging pile 301, the V2G DC charging pile 302 and the energy storage device 70 through the AC bus 50 of the sub-grid, the substation 20 and the V2G controller 10.

[0095] Please refer to FIG. 6, which is an energy flow diagram of a micro-grid system 100 in a V2G mode and local available energy storage of a sub-grid is less than or equal to the power demand of the sub-grid. FIG. 6 is an energy flow diagram of the micro-grid system 100 based on FIG. 2, if the V2G discharge amount of the vehicles in the sub-grid is just enough or less than the power demand. The V2G controller 10 does not open the discharge function to the large grid, but still opens the power request to the upper grid to prevent the power instability caused by the sudden large power consumption of the power end equipment 40 of the subsequent sub-grid. At this time, the V2G controller 10 will plan based on the task strategy of the V2G operator or the V2G service provider, distribute the time period based on the vehicle discharge capacity and the vehicle power, and require the vehicle to discharge stably according to the set power in the fixed time period until the task is completed. In FIG. 6, the V2G AC charging pile 301, the V2G DC charging pile 302 and the energy storage device 70 can supply power to the unidirectional DC charging pile 90 and the power end equipment 40, and the part of the local available energy storage of the sub-grid that cannot meet the power demand of the sub-grid can be supplied by the upper grid through the V2G controller 10, the substation 20 and the AC bus 50 of the sub-grid to the DC charging pile and the power end equipment 40.

[0096] When the micro-grid system 100 is in the emergency mode, the upper grid can have a failure problem or a maintenance outage, and the upper grid cannot supply power to the sub-grid. At this time, if the sub-grid has a hospital, communication or emergency lighting, the V2G controller 10 uses the internal energy storage of the sub-grid to work. Start arranging vehicles to participate in discharging for special emergency users. The discharge in the emergency mode is similar to the mode of V2G, and the V2G controller 10 can manage and discharge the vehicles. The energy flow of the micro-grid system 100 in the emergency mode can be seen in FIG. 5 or FIG. 6.

[0097] The scheme adopted by the embodiment of the application is to transform the transformer of the substation 20, and uniformly use the voltage standard of the rear end of the area responsible by the substation 20 for discharging. The transformer of the substation 20 is responsible for the parking lot or charging and discharging field in the area, and the charging pile for energy exchange with the vehicle is hung on the output bus of the substation 20 to realize the micro-grid system 100 in the area, and then the V2G controller 10 controls the charging and discharging of the vehicle based on the control strategy through wireless or wired network to realize peak shaving of the upper grid (large grid). Such architecture can greatly reduce the cost brought by transformation, and the cost of vehicle discharging directly connected to the output grid of the rear end of the substation 20 is much lower than that of reverse output to the large grid.

[0098] The micro-grid system 100 uploads the power to the output bus (i.e., the AC bus 50 of the sub-grid) of the last stage substation 20 (i.e., the sub-grid substation 20) to act as the input power of the rear end user, and the micro-grid system 100 delivers the discharging energy of the vehicle to the nearby power users to realize the effect of peak shaving by reducing the energy request to the upper grid (large grid). Since the sub-grid is the last stage grid, when the new energy vehicle is connected to work, it will not affect the normal work of the upper grid (large grid), and only needs to increase and decrease the scale of the V2G discharge port according to the local space and the range that the V2G discharge energy is expected to cover. The more the ports, the better the effect. The vehicle scale of the micro-grid system 100 can be large or small to realize peak shaving.

[0099] The topology used by the micro-grid system 100 optimizes the energy path of V2G. The traditional V2G energy needs to be converted multiple times before reaching the user end, and the output standard after conversion is high, which not only has large loss but also high cost. The topology of the micro-grid system 100 uses the principle of micro-grid priority power supply to make the energy consumed locally first, so that the number of conversions is less and the standard requirement is low, which greatly reduces the cost by relying on the vehicle-mounted system.

[0100] Please refer to FIG. 7, which is a comparison diagram of energy flow of the present scheme and traditional V2G technology. As shown in FIG. 7, the energy flow of the present scheme only needs to pass through energy conversion of the converter twice, while the energy flow of the traditional V2G needs to pass through energy conversion of the converter three times, thereby reducing the number of energy conversion.

[0101] The working principle of the micro-grid system 100 is to preferentially consume locally and then upload to the large power grid. If each energy storage device 70 or vehicle uploads in a separate mode, a large amount of impact on the power grid will occur, which is not conducive to reducing the operation cost of the power grid. The advantage of the topology of the micro-grid system 100 is that each sub-grid is integrated and then uses the transformer station 20 to upload each sub-grid to the power grid as the smallest uploading unit. When the local consumption is greater than or equal to the local energy storage, the micro-grid still operates in the load mode and does not need to upload energy to the large power grid, but the reduced power that needs to be input by the power grid is borne by the energy storage device 70 and the vehicle. When the local consumption is less than the energy storage, the energy is uploaded through the transformer station 20, and the number of impacts on the power grid generated by the energy uploaded by the V2G controller 10 can be greatly reduced, so that the peak load shifting of V2G discharging can be realized without increasing the operation cost of the power grid.

[0102] The micro-grid system 100 connects the V2G input port to the last stage transformer station 20 (the transformer station 20 corresponding to the sub-grid) in the power grid, and sets the scale of the corresponding power V2G parking space 01 based on the range of local electricity coverage. For example, for some old communities with tight parking spaces, in order to meet the local electricity demand, all parking spaces can be set to support the function of the V2G parking space 01. For some large commercial areas (some commercial areas with many parking spaces), there are many parking spaces, and several hundred parking spaces can meet the local electricity demand. Only 50 parking spaces need to be modified as V2G parking spaces 01. Since the modification of the V2G parking space 01 needs cost, the cost of parking space modification can be reduced. Subsequently, V2G parking spaces 01 can be added as needed. The modification of the V2G parking space 01 is bidirectional, the sub-grid can charge the vehicle, and the vehicle can also discharge to the sub-grid. When the local electricity is input through the transformer station 20, the transformer station 20 can be regarded as a power source in the micro-grid system 100. When the upper power grid is faced with disaster or forced to be shut down for modification, the new energy vehicle can replace the transformer station 20 as the last stage power grid (sub-grid) to provide electricity for the back end and reduce the power-off time.

[0103] Please refer to FIG. 8, which is a flow diagram of a control method based on the micro-grid system 100. The method shown in FIG. 8 can be based on the micro-grid system 100 shown in FIG. 1 or FIG. 2. As shown in FIG. 8, the method can include the following steps.

[0104] 801, in the case where the micro-grid system 100 is in the V2G mode, the V2G controller 10 acquires the power consumption demand of the sub-grid and the locally available energy storage of the sub-grid, the locally available energy storage of the sub-grid including the sum of the dischargeable amount of each dischargeable vehicle accessing at least one V2G charging pile 30, the power consumption demand of the sub-grid including the power consumption demand of at least one power consumption terminal 40.

[0105] In the embodiments of the present application, the dischargeable vehicle is a vehicle supporting V2G discharge. It should be noted that some vehicles accessing the V2G charging pile 30 may not support V2G discharge. The dischargeable amount of the dischargeable vehicle is the amount of electricity that the vehicle supporting V2G discharge can use for V2G discharge. For example, the total amount of electricity of the vehicle supporting V2G discharge is 100%, and the amount of electricity that the vehicle can use for V2G discharge is 80%.

[0106] The sum of the dischargeable amount of each dischargeable vehicle accessing at least one V2G charging pile 30 refers to the sum of the dischargeable amount of all dischargeable vehicles accessing at least one V2G charging pile 30.

[0107] 802, the V2G controller 10 allocates a discharge task to each dischargeable vehicle according to the power consumption demand and the locally available energy storage, so that each dischargeable vehicle is used to discharge to the AC bus 50 of the sub-grid based on the allocated discharge task.

[0108] In the embodiments of the present application, when the micro-grid system 100 is in the V2G mode, the dischargeable vehicle in the micro-grid system 100 discharges to the AC bus 50 of the sub-grid. The discharge of the dischargeable vehicle to the AC bus 50 of the sub-grid can directly bear the power consumption demand of the sub-grid. Compared with the discharge of the dischargeable vehicle to the upper-level power grid, on the one hand, the impact of the discharge of the dischargeable vehicle to the upper-level power grid on the upper-level power grid can be avoided, and on the other hand, the number of energy conversion can be reduced, thereby reducing the operation cost of the power grid.

[0109] Optionally, the method shown in FIG. 8 further includes the following steps:

[0110] (11) In the case where the locally available energy storage of the sub-grid is greater than the power consumption demand, the V2G controller 10 determines that the upper-level power grid needs to send power in reverse according to the load state of the power grid.

[0111] (12) In the case where the upper-level power grid needs to send power in reverse, the V2G controller 10 controls each dischargeable vehicle to input the excess discharge amount to the transformer substation 20 through the AC bus 50 of the sub-grid, and then upload to the power transmission line 60 of the upper-level power grid; the excess discharge amount is less than or equal to the first difference, and the first difference is the difference between the sum of the dischargeable amount and the power consumption demand of the sub-grid.

[0112] Optionally, the method shown in FIG. 8 further comprises the following steps:

[0113] In the case that the local available energy storage of the sub-grid is less than or equal to the power demand, the V2G controller 10 opens a power request to the upper grid and closes the reverse power transmission function of the sub-grid to the upper grid.

[0114] Optionally, the method shown in FIG. 8 further comprises the following steps:

[0115] In the case that the micro-grid system 100 is in the load mode, the V2G controller 10 enters the sleep state, and the power of all power consumption devices in the sub-grid is derived from the upper grid.

[0116] Optionally, the method shown in FIG. 8 further comprises the following steps:

[0117] In the case that the micro-grid system 100 is in the emergency mode, the V2G controller 10 acquires the power demand of the sub-grid and the local available energy storage of the sub-grid, and preferentially supplies power to the power consumption devices with high priority in the sub-grid.

[0118] Optionally, the discharging task comprises a discharging period and a discharging power; and step 802 can specifically comprise the following steps:

[0119] The V2G controller 10 controls each discharging vehicle to discharge to the AC bus 50 of the sub-grid according to the assigned discharging period and the assigned discharging power based on the power demand and the local available energy storage, and the sum of the cumulative discharging amounts of each discharging vehicle in the assigned discharging period is less than or equal to the power demand.

[0120] Optionally, the method shown in FIG. 8 further comprises the following steps:

[0121] The V2G controller 10 assigns a power supply task to the energy storage device 70 based on the power demand and the local available energy storage, so that the energy storage device 70 supplies power to the unidirectional DC charging pile 90 based on the assigned power supply task.

[0122] The above describes the scheme of the embodiment of the application from the perspective of the method side execution process. It can be understood that the V2G controller 10 includes hardware structures and / or software modules corresponding to the execution of each function in order to implement the above functions. Those skilled in the art should easily realize that, in combination with the unit and algorithm steps of each example described in the embodiments provided herein, the application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a certain function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the application.

[0123] The embodiment of the application can divide the functional units of the V2G controller 10 according to the above method examples. For example, each functional unit can be divided according to each function, or two or more functions can be integrated in one processing unit. The integrated unit can be implemented in the form of hardware or software functional unit. It should be noted that the division of units in the embodiment of the application is illustrative, and is only a logical functional division. Actual implementation can have another division manner.

[0124] Referring to FIG. 9, FIG. 9 is a structural schematic diagram of a V2G controller 10 provided by the embodiment of the application. As shown in FIG. 9, the V2G controller 10 includes a processor 901 and a memory 902, and the processor 901 and the memory 902 can be connected to each other through a communication bus 903. The communication bus 903 can be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The communication bus 903 can be divided into an address bus, a data bus, a control bus, etc. For convenience of representation, only one thick line is used in FIG. 9, but it does not mean that there is only one bus or only one type of bus. The memory 902 is used to store computer instructions, and the processor 901 is configured to invoke the computer instructions. The above program includes instructions for executing part or all of the steps in the method shown in FIG. 8.

[0125] The processor 901 can be a general central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of the above scheme program. Specifically, the processor 901 can be a VCU.

[0126] The memory 902 can be a read-only memory (ROM) or other type of static storage device that can store static information and instructions, a random access memory (RAM) or other type of dynamic storage device that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disk storage, a magnetic disk storage or other magnetic storage devices, or any other medium capable of storing desired program code in the form of instructions or data structures and that can be accessed by a computer, but is not limited thereto. The memory can exist independently of the processor, and be connected to the processor via a bus. The memory can also be integrated with the processor.

[0127] In the embodiment of the application, when the micro-grid system 100 is in the V2G mode, the dischargeable vehicle in the micro-grid system 100 discharges to the AC bus 50 of the sub-grid, and the discharge of the dischargeable vehicle to the AC bus 50 of the sub-grid can directly bear the power demand of the sub-grid. Compared with the discharge of the dischargeable vehicle to the upper grid, on the one hand, the impact of the discharge of the dischargeable vehicle to the upper grid on the upper grid can be avoided, and on the other hand, the number of energy conversion can be reduced, thereby reducing the operation cost of the grid.

[0128] The embodiment of the application also provides a computer readable storage medium, wherein the computer readable storage medium stores computer instructions for electronic data exchange, and the computer instructions enable a computer to execute part or all steps of any one of the control methods based on the micro-grid system as described in the above method embodiments.

[0129] The embodiment of the application also provides a computer instruction product, wherein the computer instruction product includes any one of the computer instructions as described above, and the computer instructions are operable to enable a computer to execute part or all steps of any one of the control methods based on the micro-grid system as described in the above method embodiments.

[0130] It should be noted that, for the foregoing method embodiments, the sequences of the described actions are not necessarily required to achieve the objects of the application, and certain steps can be performed in other sequences or even concurrently. Additionally, the described embodiments are merely provided as examples, and not all of the actions described are necessarily required to achieve desired results.

[0131] In the above embodiments, the description of each embodiment is focused on different aspects, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0132] In several embodiments provided in the present application, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, another division manner can be adopted. For example, a plurality of units or components can be combined or integrated into another system, or some features can be omitted or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interfaces, apparatuses or units, and can be electrical or other forms.

[0133] The units described as separate components can or can not be physically separate, and the components shown as units can or can not be physical units, i.e. can be located in one place or distributed on a plurality of network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0134] In addition, the functional units in each embodiment of the application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software program module.

[0135] If the integrated unit is realized in the form of a software program module and sold or used as an independent product, it can be stored in a computer readable memory. Based on this understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a memory and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned memory includes: a U disk, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk, and various media that can store program codes.

[0136] A person of ordinary skill in the art can understand that all or part of the steps of the various methods of the above embodiments can be completed by instructing the relevant hardware through a program, and the program can be stored in a computer readable memory, and the memory can include a flash disk, a read-only memory, a random access memory, a magnetic disk or an optical disk, etc.

[0137] The embodiments of the present application are described in detail above, and the principles and implementation manners of the present application are described by applying specific examples. The above description of the embodiments is only used to help understand the method of the present application and its core idea; meanwhile, for those of ordinary skill in the art, according to the idea of the present application, the specific implementation manner and application range will be changed, and the above description of the embodiments should not be understood as a limitation of the present application.

Claims

1. A microgrid system (100), wherein, include: The vehicle-to-grid V2G controller (10), substation (20), at least one V2G charging pile (30) and at least one power-consuming device (40); The substation is connected to the V2G charging pile and the power-consuming equipment via the AC bus (50) of the sub-grid; When the microgrid system is in V2G mode, the V2G controller obtains the power demand of the subgrid and the local available energy storage of the subgrid. The local available energy storage of the subgrid includes the sum of the discharge capacity of each dischargeable vehicle connected to the at least one V2G charging pile. The power demand of the subgrid includes the power demand of the at least one power-consuming device. The V2G controller assigns a discharge task to each of the dischargeable vehicles based on the power demand and the available local energy storage, so that each of the dischargeable vehicles discharges to the AC bus of the sub-grid based on the assigned discharge task.

2. The microgrid system according to claim 1, wherein, The microgrid system also includes transmission lines (60) of the upper-level power grid, which are connected to the substation via the V2G controller.

3. The microgrid system according to claim 2, wherein: If the available local energy storage is greater than the electricity demand, the V2G controller determines whether the upstream grid needs to send power in reverse based on the load status of the upstream grid. In the event that the upstream power grid needs to send power in reverse, the V2G controller controls each of the dischargeable vehicles to input the excess discharge capacity into the substation through the AC bus of the sub-grid, so as to transmit it to the transmission line of the upstream power grid. The excess discharge amount is less than or equal to a first difference, which is the difference between the sum of the dischargeable amounts and the power demand of the subgrid.

4. The microgrid system according to claim 2 or 3, wherein, When the available local energy storage is less than or equal to the electricity demand, the V2G controller initiates an electricity demand request to the upstream power grid and disables the reverse power transmission function from the subgrid to the upstream power grid.

5. The microgrid system according to any one of claims 2 to 4, wherein, The discharge task includes a discharge period and a discharge power. Each of the dischargeable vehicles discharges to the AC bus of the subgrid based on the assigned discharge task, including: Each of the dischargeable vehicles discharges to the AC bus of the subgrid according to the allocated discharge power during the allocated discharge period, and the sum of the cumulative discharge of each of the dischargeable vehicles during the allocated discharge period is less than or equal to the electricity demand.

6. The microgrid system according to any one of claims 2 to 5, wherein, When the microgrid system is in load mode, the V2G controller enters a sleep state, and the power supply for all electrical devices in the subgrid comes from the upstream power grid.

7. The microgrid system according to any one of claims 1 to 6, wherein, When the microgrid system is in emergency mode, the V2G controller obtains the power demand of the subgrid and the local available energy storage of the subgrid, and prioritizes power supply to the high-priority electrical equipment of the subgrid.

8. The microgrid system according to any one of claims 1 to 7, wherein, The at least one V2G charging pile and the AC bus of the sub-grid use the same voltage standard.

9. The microgrid system according to any one of claims 1 to 8, wherein, The microgrid system also includes: Energy storage device (70), at least one green power generation device (80) and at least one unidirectional DC charging pile (90); The at least one green power generation device is connected to the input end of the energy storage device, and the substation is connected to the energy storage device, the at least one green power generation device and the at least one unidirectional DC charging pile through the sub-grid AC bus. The at least one unidirectional DC charging pile is connected to at least one charging parking space. The local available energy storage of the subgrid also includes the available energy storage of the energy storage device, and the power demand of the subgrid also includes the power demand of the at least one unidirectional DC charging pile.

10. The microgrid system according to claim 9, wherein, The at least one V2G charging pile includes at least one V2G AC charging pile (301) and / or at least one V2G DC charging pile (302); The at least one V2G AC charging pile is connected to at least one V2G parking space (01), and the at least one V2G DC charging pile is connected to at least one V2G parking space. At least one first output terminal of the energy storage device is connected to the input terminal of the at least one V2G DC charging pile, and at least one second output terminal of the energy storage device is connected to the input terminal of the at least one unidirectional DC charging pile.

11. A control method based on a microgrid system, wherein, include: When the microgrid system is in V2G mode, the V2G controller obtains the power demand of the subgrid and the local available energy storage of the subgrid. The local available energy storage of the subgrid includes the sum of the discharge capacity of each dischargeable vehicle connected to at least one V2G charging pile. The power demand of the subgrid includes the power demand of at least one power-consuming device. The V2G controller assigns a discharge task to each of the dischargeable vehicles based on the power demand and the available local energy storage, so that each of the dischargeable vehicles can discharge to the AC bus of the subgrid based on the assigned discharge task.

12. The method according to claim 11, wherein, The method further includes: If the available local energy storage exceeds the electricity demand, the V2G controller determines that the upstream power grid needs to send power in reverse based on the load status of the upstream power grid. When the upstream power grid needs to send power in reverse, the V2G controller controls each of the dischargeable vehicles to input excess discharge capacity into the substation through the AC bus of the subgrid, so as to transmit it to the transmission line of the upstream power grid. The excess discharge capacity is less than or equal to a first difference, which is the difference between the sum of the dischargeable capacity and the power demand of the subgrid.

13. The method according to claim 11 or 12, wherein, The method further includes: When the available local energy storage is less than or equal to the electricity demand, the V2G controller sends an electricity request to the upper-level power grid and disables the reverse power transmission function from the subgrid to the upper-level power grid.

14. The method according to any one of claims 11 to 13, wherein, The discharge task includes the discharge period and discharge power; The V2G controller assigns a discharge task to each of the dischargeable vehicles based on the power demand and the available local energy storage, so that each of the dischargeable vehicles can discharge to the AC bus of the sub-grid based on the assigned discharge task, including: The V2G controller controls each of the dischargeable vehicles to discharge to the AC bus of the sub-grid during the allocated discharge period according to the power demand and the available local energy storage. The sum of the cumulative discharge of each dischargeable vehicle during the allocated discharge period is less than or equal to the power demand.

15. The method according to any one of claims 11 to 14, wherein, The method further includes: When the microgrid system is in load mode, the V2G controller enters a sleep state, and the power supply for all electrical devices in the subgrid comes from the upstream power grid.

16. The method according to any one of claims 11 to 15, wherein, The method further includes: When the microgrid system is in emergency mode, the V2G controller obtains the power demand of the subgrid and the local available energy storage of the subgrid, and prioritizes power supply to the high-priority electrical equipment of the subgrid.

17. The method according to any one of claims 11 to 16, wherein, The method further includes: The V2G controller allocates power supply tasks to the energy storage device based on the power demand and the available local energy storage, so that the energy storage device supplies power to the unidirectional DC charging pile based on the allocated power supply tasks.

18. A V2G controller (10) in a microgrid system as described in any one of claims 1 to 10, wherein, It includes a processor (901) and a memory (902), the memory being used to store computer instructions, and the processor being configured to invoke the computer instructions to perform the method as described in any one of claims 11 to 17.

19. A computer-readable storage medium, wherein, The computer-readable storage medium stores computer instructions that, when executed by a processor, cause the processor to perform the method as described in any one of claims 11 to 17.

20. A computer instruction product comprising the computer instructions as described in claim 18 or 19, wherein, The computer instructions are operable to cause the computer to perform the method as described in any one of claims 11 to 17.

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