Transformer area voltage control method, control equipment and energy storage system

Abstract

The embodiment of the invention provides a transformer area voltage control method, control equipment and an energy storage system, and relates to the technical field of power electronics. The method comprises the following steps: determining the real-time total charging load power of each transformer area according to the first real-time operation power of each transformer area and the second real-time operation power of each transformer area; according to the tripping power threshold value of each transformer area and the real-time charging load power of each transformer area, the allowable operation power of the flexible interconnection device in each transformer area is determined; and according to the allowable operation power of the flexible interconnection device in each transformer area and the second real-time operation power of each transformer area, adjusting the real-time operation power of the charging equipment in each transformer area, so that the adjusted first real-time operation power of each transformer area does not exceed the tripping power threshold value of each transformer area. Therefore, the real-time operation power of the charging equipment in each district is stable, and the stability and quality of the electric energy of each charging station are ensured during the operation of each charging station.

Description

Technical Field

[0001] The present application relates to the field of power electronics technology, and in particular to a substation voltage control method, a control device, and an energy storage system. Background Art

[0002] The demand for new energy vehicles and new energy vehicle charging stations continues to increase, which puts higher requirements on the real-time operating power output of new energy charging stations.

[0003] In the prior art, corresponding flexible interconnection devices are configured according to the rated power and load rate constraint requirements of the transformers in multiple substations to realize power transfer between multiple substations, and then adjust the real-time operating power of the transformers in each substation, ensure the normal operation of the load as much as possible when the transformer is in a stable state, and improve the charging demand of new energy vehicles and the power demand of other loads in each substation.

[0004] However, this approach cannot overcome the impact of a sudden increase or decrease in charging load in each area within a high-power charging station on the grid connection point, making it easy for the transformer to experience large power fluctuations during actual operation. In addition, the existing technology cannot constrain the charging power of each area within a high-power charging station, which is likely to cause the transformer to overload or trip when charging at a high-power charging station with a large charging demand. This is extremely inflexible for increasing the charging power configuration of each area within the charging station, that is, the existing technology solution is not suitable for the high-power charging demand of each area within a high-power charging station and the stable configuration of the transformer in each area. Summary of the invention

[0005] The purpose of the present application includes, for example, providing a substation voltage control method, control equipment and energy storage system, which can adjust the real-time operating power of the charging equipment in each substation according to the allowed operating power of the flexible interconnection device in each substation and the second real-time operating power of each substation, so that the first real-time operating power of each substation after adjustment does not exceed the tripping power threshold of each substation, thereby stabilizing the real-time operating power of the charging equipment in each substation, thereby ensuring the stability and quality of the electric energy of each charging station when each charging station is in operation.

[0006] In order to achieve the above purpose, the technical solution adopted in the embodiment of the present application is as follows:

[0007] In a first aspect, an embodiment of the present application provides a method for controlling a voltage in a metropolitan area, comprising:

[0008] Determine the real-time total charging load power of each substation according to the first real-time operating power of each substation and the second real-time operating power of each substation, wherein the first real-time operating power is the real-time operating power of the transformer in each substation, the second real-time operating power is the real-time operating power of the flexible interconnection device in each substation, and the real-time total charging load power is the real-time charging load power of all charging devices in each substation;

[0009] Determine the allowable operating power of the flexible interconnection device in each substation according to the trip power threshold of each substation and the real-time charging load power of each substation;

[0010] According to the allowed operating power of the flexible interconnection device in each substation and the second real-time operating power of each substation, the real-time operating power of the charging equipment in each substation is adjusted so that the first real-time operating power of each substation after adjustment does not exceed the tripping power threshold of each substation.

[0011] Optionally, the method further comprises:

[0012] Determine the allowable transfer power of the flexible interconnection device in each area according to the allowable operating power of the flexible interconnection device in each area and the preset hysteresis power of each area;

[0013] Determine the power difference of each substation according to the trip power threshold of each substation and the preset hysteresis power of each substation;

[0014] Determine whether each of the stations meets a preset overload condition according to the power difference of each of the stations and the real-time charging load power of each of the stations;

[0015] If the preset overload condition is not satisfied in each of the sections, the flexible interconnection devices in each section are controlled to be in a shutdown state.

[0016] Optionally, determining whether each of the substations meets the preset overload condition according to the power difference of each substation and the real-time charging load power of each substation includes:

[0017] Determine whether the real-time charging load power of each of the stations is greater than or equal to the power difference of each of the stations;

[0018] If it is greater than or equal to the power difference of each of the substations, it is determined that each of the substations meets the preset overload condition;

[0019] If it is less than the power difference of each of the stations, it is determined that each of the stations does not meet the preset overload condition.

[0020] Optionally, the method further comprises:

[0021] If the first substation among the substations meets the preset overload condition, the required transfer power of the first substation is determined according to the trip power threshold of the first substation, the hysteresis power of the first substation and the real-time charging load power of the first substation;

[0022] Determine target transfer conditions satisfied by the first substation and the second substation according to the required transfer power of the first substation and the allowable transfer power of the flexible interconnection device in the second substation;

[0023] According to the target power transfer condition, determining the set power transfer of the first substation and the set power transfer of the second substation;

[0024] According to the set transfer power of the first area and the set transfer power of the second area, a control signal of the flexible interconnection device in the first area and a control signal of the flexible interconnection device in the second area are generated respectively.

[0025] Optionally, determining the target transfer conditions satisfied by the first and second substations according to the required transfer power of the first substation and the allowed transfer power of the flexible interconnection device in the second substation includes:

[0026] If the required transfer power of the first area is less than the allowed transfer power of the flexible interconnection device in the second area, determining the target transfer condition to be the first transfer condition;

[0027] The step of determining the set transfer power of the first area and the set transfer power of the second area according to the target transfer condition includes:

[0028] Under the first transfer condition, the set transfer power of the first substation and the set transfer power of the second substation are determined according to the required transfer power of the first substation.

[0029] Optionally, determining the target transfer conditions satisfied by the first and second substations according to the required transfer power of the first substation and the allowed transfer power of the flexible interconnection device in the second substation includes:

[0030] If the required transfer power of the first area is greater than or equal to the allowed transfer power of the flexible interconnection device in the second area, determine whether the allowed transfer power of the flexible interconnection device in the second area exceeds a preset multiple of the hysteresis power of the first area;

[0031] If the allowable transfer power of the flexible interconnection device in the second station area exceeds the preset multiple of the hysteresis power of the first station area, determining the target transfer condition to be the second transfer condition;

[0032] The step of determining the set transfer power of the first area and the set transfer power of the second area according to the target transfer condition includes:

[0033] Under the second transfer condition, the set transfer power of the first area and the set transfer power of the second area are determined according to the difference between the allowed transfer power of the flexible interconnection device in the second area and the hysteresis power of the second area.

[0034] Optionally, the determining the target transfer conditions satisfied by the first and second substations according to the required transfer power of the first substation and the allowed transfer power of the flexible interconnection device in the second substation further includes:

[0035] If the allowable transfer power of the flexible interconnection device in the second station area is less than the preset multiple of the hysteresis power of the first station area, but greater than or equal to the hysteresis power of the first station area, then determining that the target transfer condition is the third transfer condition;

[0036] The step of determining the set transfer power of the first area and the set transfer power of the second area according to the target transfer condition includes:

[0037] Under the third transfer condition, the set transfer power of the first substation and the set transfer power of the second substation are determined according to the allowed transfer power of the flexible interconnection device in the second substation.

[0038] Optionally, adjusting the real-time operating power of the charging equipment in each area according to the allowed operating power of the flexible interconnection device in each area and the second real-time operating power of each area includes:

[0039] According to the allowed operating power of the flexible interconnection device in each area and the second real-time operating power of each area, respectively updating the limited operating power of the charging equipment under each area;

[0040] The smaller of the limited operating power of the charging equipment in each area and the rated operating power of the corresponding charging equipment is taken to obtain the real-time operating power of the charging equipment in each area.

[0041] In a second aspect, an embodiment of the present application provides a control device, comprising: a processor; and a memory communicatively connected to the processor; wherein the memory stores a computer program executable by the processor, and the computer program is executed by the processor so that the processor can execute the substation voltage control method described in any one of the first aspects.

[0042] In a third aspect, an embodiment of the present application provides an energy storage system, the energy storage system comprising: transformers in multiple substations, multiple charging devices, multiple flexible interconnection devices, and the control device described in the second aspect above;

[0043] Among them, the transformers in the multiple substations are respectively connected to the flexible interconnection devices in their respective substations, and the transformers in the multiple substations are respectively connected to the charging equipment in their respective substations; the control device is communicatively connected with the transformers in the multiple substations, the multiple flexible interconnection devices and the multiple charging equipment; the control device is used to execute the substation voltage control method described in any one of the first aspects.

[0044] The beneficial effects of the embodiments of the present application include, for example:

[0045] The embodiment of the present application provides a substation voltage control method, control device and energy storage system, which relates to the field of power electronics technology. The first real-time operating power of the transformer in each substation and the second real-time operating power of the flexible interconnection device in each substation are obtained, and the real-time total charging load power of all charging devices in each substation is calculated according to the following formula (1); then, according to the tripping power threshold of the transformer in each substation and the real-time charging load power of all charging devices in each substation, the allowable operating power of the flexible interconnection device in each substation is calculated according to the following formula (3); according to the allowable operating power of the flexible interconnection device in each substation and the second real-time operating power of the flexible interconnection device in each substation, the real-time operating power of the charging device in each substation is adjusted, so that the first real-time operating power of the transformer in each substation does not exceed the tripping power threshold of each substation after adjustment, thereby stabilizing the real-time operating power of the charging equipment in each substation, thereby ensuring the stability and quality of the electric energy of each charging station when each charging station is in operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0047] Figure 1 A schematic diagram of the structure of an energy storage system provided in an embodiment of the present application;

[0048] Figure 2 A schematic diagram of the structure of a control device provided in an embodiment of the present application;

[0049] Figure 3 A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 1 ;

[0050] Figure 4 A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 2 ;

[0051] Figure 5 A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 3 ;

[0052] Figure 6 A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 4 ;

[0053] Figure 7 A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 5 ;

[0054] Figure 8 A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 6 ;

[0055] Fig. 9 A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 7 ;

[0056] Fig.10 A schematic diagram of the structure of a substation voltage control device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0057] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0058] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0059] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0060] In the description of the present application, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear to indicate an orientation or position relationship, it is based on the orientation or position relationship shown in the drawings, or is the orientation or position relationship in which the product of the invention is usually placed when used. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0061] In addition, the terms “first”, “second”, etc., if used, are merely used to distinguish between the descriptions and should not be understood as indicating or implying relative importance.

[0062] It should be noted that, in the absence of conflict, the features in the embodiments of the present application may be combined with each other.

[0063] In order to clearly describe a substation voltage control method, a control device, and an energy storage system provided in an embodiment of the present application, the energy storage system is first described in detail with reference to the accompanying drawings. Figure 1 This is a schematic diagram of the structure of an energy storage system provided in an embodiment of the present application. Figure 1 As shown, the energy storage system 200 may include: transformers 210 in multiple substations, multiple charging devices 220 , multiple flexible interconnection devices 230 , and a control device 100 .

[0064] The transformers 210 in the multiple areas are connected to the flexible interconnection devices 230 in the respective areas; the transformers 210 in the multiple areas are connected to the charging devices 220 in the respective areas to provide available electrical signals to the charging devices 220 in the respective areas; the control device 100 is connected to the transformers 210, the multiple flexible interconnection devices 230 and the multiple charging devices 220 in the multiple areas in communication to collect data of the transformers 210, the multiple flexible interconnection devices 230 and the multiple charging devices 220 in the multiple areas (such as the real-time electrical parameters of each area (DC active power, AC active power, reactive power, AC voltage, DC voltage, etc.) and operation status of each area), and the charging devices 220 in each area and the multiple charging devices 220 are controlled according to the collected data. For example, the flexible interconnection devices 230 in each area are monitored, and the control mode and flow regulation target of the flexible interconnection devices 230 are adjusted according to the operation mode and flow optimization principle.

[0065] It should be noted that the control device 100 in the embodiment of the present application can be understood as the control device in the energy storage system 200, and can also be understood as the control unit in the flexible interconnection device 230. If the control device 100 is the control unit in the flexible interconnection device 230, the control device in the energy storage system 200 can be directly connected to the control unit in the flexible interconnection device 230, and the control device can be used as an upper-level instruction issuing device for the substation control protection device. In addition, it should be noted that the communication connection between the control device 100 and the transformers 210, multiple flexible interconnection devices 230 and multiple charging devices 220 in multiple substations can be set up with a communication management line (such as RS485) to communicate with the transformers 210, multiple flexible interconnection devices 230 and multiple charging devices 220 in multiple substations, and then the communication management line is used to communicate with the control device 100. This connection method cannot be understood as a limitation to the present application.

[0066] The control device 100 is used to execute the area voltage control method. The control device 100 can be selected according to actual conditions, for example, the control device 100 can be selected as an EMS (energy management system); the charging device 220 can be selected as a charging pile; the flexible interconnection device 230 can be selected according to actual conditions, for example, the flexible interconnection device 230 can be selected as an AC / DC (ACDC) converter.

[0067] It should be noted that, in real-time operation, in order to save equipment resources and prevent equipment instability, the calculation cycle of active power is set. To meet the needs of actual applications, the calculation cycle of the flexible interconnection device 230 is smaller than the active power calculation cycle of the charging device. For example, the calculation cycle of the flexible interconnection device 230 is 2S, and the calculation cycle of the charging device is 4S for charging.

[0068] The energy storage system provided in the embodiment of the present application is composed of transformers in multiple substations, multiple charging devices, multiple flexible interconnection devices and a control device; wherein the transformers in the multiple substations are respectively connected to the flexible interconnection devices in their respective substations, and the transformers in the multiple substations are respectively connected to the charging devices in their respective substations; the control device is communicatively connected with the transformers in the multiple substations, the multiple flexible interconnection devices and the multiple charging devices; the control device is used to execute the substation voltage control method to ensure the stability and reliability of each substation in the energy storage system during operation.

[0069] Furthermore, in order to clearly describe the energy storage system 200 provided in the above embodiment, the present application also provides a structural schematic diagram of a control device 100. Figure 2 This is a schematic diagram of the structure of a control device provided in an embodiment of the present application. Figure 2 As shown, the control device 100 may include: a processor 110 and a memory 120 .

[0070] The memory 120 stores machine executable instructions that can be executed by the processor 110, that is, when the control device 100 is running, the above machine readable instructions are executed, and the processor 110 communicates with the memory 120 via a bus. The processor 110 can execute the machine executable instructions to implement the station voltage control method.

[0071] Among them, the memory 120, the processor 110 and the bus components are electrically connected to each other directly or indirectly to realize data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses or signal lines. The mobile storage device includes at least one software function module that can be stored in the memory 120 in the form of software or firmware or solidified in the operating system (OS) of the electronic device. The processor 110 is used to execute the executable modules stored in the memory 120, such as the software function modules and computer programs included in the station area voltage control method of the mobile storage medium.

[0072] Among them, the memory 120 can be, but is not limited to, random access memory (Random Access Memory, RAM), read only memory (Read Only Memory, ROM), programmable read-only memory (Programmable Read-Only Memory, PROM), erasable programmable read-only memory (Erasable Programmable Read-Only Memory, EPROM), electrically erasable read-only memory (Electric Erasable Programmable Read-Only Memory, EEPROM), etc.

[0073] The substation voltage control method provided in the embodiment of the present application may be executed by the processor 110 in the control device 100. The substation voltage control method provided in the above embodiment of the present application is explained and illustrated in detail below in conjunction with the accompanying drawings. Figure 3 A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 1 .like Figure 3 As shown, the method may include:

[0074] S301. Determine the real-time total charging load power of each substation according to the first real-time operating power of each substation and the second real-time operating power of each substation.

[0075] Among them, the first real-time operating power Prun_tfx is the real-time operating power of the transformer in each substation, the second real-time operating power Prun_FIDx is the real-time operating power of the flexible interconnection device in each substation, and the real-time total charging load power Pload_tfx is the real-time charging load power of all charging equipment (i.e., charging stations) in each substation.

[0076] In one possible implementation, the first real-time operating power Prun_tfx of the transformer corresponding to X substations and the second real-time operating power Prun_FIDx of the corresponding flexible interconnection device are obtained, and the real-time total charging load power Pload_tfx of the charging stations in the X substations is calculated by the following formula (1).

[0077] Pload_tfx=Prun_tfx-Prun_FIDx Formula (1)

[0078] Refer to the above Figure 1 First, obtain the first real-time operating power Prun_tf1 of the transformer corresponding to the A station area and the second real-time operating power Prun_FID1 of the flexible interconnection device in the A station area, then obtain the first real-time operating power Prun_tf2 of the transformer corresponding to the B station area and the second real-time operating power Prun_FID2 of the flexible interconnection device in the B station area, and then calculate the real-time total charging load power Pload_tfx of the charging stations in the two stations according to the above formula (1), that is, the real-time total charging load power Pload_tf1 of the charging stations in the A station area = Prun_tf1-Prun_FID1; the real-time total charging load power Pload_tf2 of the charging stations in the B station area = Prun_tf2-Prun_FID2.

[0079] S302: Determine the allowable operating power of the flexible interconnection device in each substation according to the tripping power threshold of each substation and the real-time charging load power of each substation.

[0080] The trip power threshold Prate_tfx of the transformer in each substation can be obtained by multiplying the rated power of the transformer in each substation by the preset load rate of each substation. For example, the trip power threshold Prate_tfx of each substation is determined according to the following formula (2).

[0081] Prate_tfx = rated power of transformer * preset load rate of charging equipment Formula (2)

[0082] The preset load rate in the above formula (2) can be selected according to the actual situation. For example, the preset load rate can be selected as 0.85 or 0.8. When the preset load rate is 0.85, the charging equipment in each area starts to operate; when the preset load rate is 0.8, the flexible interconnection device in each area starts to operate.

[0083] For example, when the rated power of the transformer is 630 KVA and the preset load rate of the charging equipment is 0.85, the tripping power threshold of each substation is Prate_tfx=630*0.85=535.5 KVA.

[0084] In one possible implementation, after obtaining the real-time charging load power Pload_tfx of each substation, the allowable operating power Pallow_tfx of the flexible interconnection device in each substation can be determined according to the tripping power threshold Prate_tfx of the transformer in each substation by the following formula (3).

[0085] Pallow_tfx=Prate_tfx-Pload_tfx formula (3)

[0086] Continue to refer to the above Figure 1 , obtain the real-time total charging load power Pload_tf1 of the charging station in area A and the tripping power threshold Prate_tf1 in area A; then obtain the real-time total charging load power Pload_tf2 of the charging station in area B and the tripping power threshold Prate_tf2 of area B, and then calculate the allowable operating power Pallow_tfx of the flexible interconnection devices in the two areas according to the above formula (3), that is, the allowable operating power Pallow_tf1 of the flexible interconnection device in area A = Prate_tf1-Pload_tf1; the allowable operating power Pallow_tf2 of the flexible interconnection device in area B = Prate_tf2-Pload_tf2.

[0087] S303: According to the allowed operating power of the flexible interconnection device in each substation and the second real-time operating power of each substation, the real-time operating power of the charging equipment in each substation is adjusted so that the first real-time operating power of each substation after adjustment does not exceed the tripping power threshold of each substation.

[0088] In one possible implementation, after obtaining the allowable operating power Pallow_tfx of the flexible interconnection device in each substation, the real-time operating power Prun_chg_tfx of the charging equipment in each substation is adjusted according to the second real-time operating power Prun_FIDx of each substation, so that the adjusted first real-time operating power Prun_tfx of each substation does not exceed the tripping power threshold Prate_tfx of each substation.

[0089] The embodiment of the present application provides a substation voltage control method, which obtains the first real-time operating power of the transformer in each substation and the second real-time operating power of the flexible interconnection device in each substation, and calculates the real-time total charging load power of all charging devices in each substation according to the above formula (1); then, according to the tripping power threshold of the transformer in each substation and the real-time charging load power of all charging devices in each substation, the allowable operating power of the flexible interconnection device in each substation is calculated according to the above formula (2); according to the allowable operating power of the flexible interconnection device in each substation and the second real-time operating power of the flexible interconnection device in each substation, the real-time operating power of the charging equipment in each substation is adjusted, so that the first real-time operating power of the transformer in each substation does not exceed the tripping power threshold of each substation after adjustment, thereby stabilizing the real-time operating power of the charging equipment in each substation, thereby ensuring the stability and quality of the electric energy of each charging station when each charging station is in operation.

[0090] The following is a detailed explanation and description of the substation voltage control method provided in the above embodiment of the present application in conjunction with the accompanying drawings. Figure 4 A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 2 .like Figure 4 As shown, the above method may also include:

[0091] S401, determining the allowable transfer power of the flexible interconnection device in each substation according to the allowable operating power of the flexible interconnection device in each substation and the preset hysteresis power of each substation.

[0092] The preset hysteresis power Pdiff_tfx can be determined based on the difference between the preset load rate of the flexible interconnection device in each area and the preset load rate of the charging equipment in each area, as well as the rated power of the transformer in each area. For example, the preset hysteresis power Pdiff_tfx of each area is determined according to the following formula (4).

[0093] Pdiff_tfx = (preset load rate of charging equipment - preset load rate of flexible interconnection device) * rated power of transformer (4)

[0094] For example, when the rated power of the transformer is 630KVA, the preset load rate of the charging equipment is 0.85, and the preset load rate of the flexible interconnection device is 0.8, then the preset differential power Pdiff_tfx of each substation is 630*(0.85-0.8)=31.5KVA.

[0095] In one possible implementation, the allowable transfer power Pallow_exch_tfx of the flexible interconnection device in each substation is determined by the following formula (5) based on the allowable operating power Pallow_tfx of the flexible interconnection device in each substation and the preset hysteresis power Pdiff_tfx (such as 31.5KVA) of each substation.

[0096] Pallow_exch_tfx=Pallow_tfx-Pdiff_tfx formula (5)

[0097] Continue to refer to the above Figure 1 , obtain the allowable operating power Pallow_tf1 of the flexible interconnection device in the A area and the preset hysteresis power Pdiff_tf1 in the A area; then obtain the allowable operating power Pallow_tf2 of the flexible interconnection device in the B area and the preset hysteresis power Pdiff_tf2 in the B area, and then calculate the allowable transfer power Pallow_exch_tfx of the flexible interconnection devices in the two areas according to the above formula (5), that is, the allowable transfer power Pallow_exch_tf1 of the flexible interconnection device in the A area = Pallow_tf1-Pdiff_tf1; Pallow_exch_tf2 of the flexible interconnection device in the B area = Pallow_tf2-Pdiff_tf2.

[0098] S402: Determine the power difference of each substation according to the trip power threshold of each substation and the preset hysteresis power of each substation.

[0099] In a possible implementation, the power difference ΔPx of each substation is determined by the following formula (6) according to the trip power threshold Prate_tfx of each substation and the preset hysteresis power Pdiff_tfx of each substation.

[0100] ΔPx=Prate_tfx-Pdiff_tfx Formula (6)

[0101] For example, the trip power threshold value Prate_tfx is 535.5KVA, and the preset differential power Pdiff_tfx is 31.5KVA, then the power difference value of each substation ΔPx=535.5KVA-31.5KVA=504KVA.

[0102] S403: Determine whether each substation meets a preset overload condition based on the power difference of each substation and the real-time charging load power of each substation.

[0103] In one possible implementation, based on the power difference ΔPx of each area and the real-time charging load power Pload_tfx of all charging devices in each area, it is determined whether each area meets the preset overload condition. If not, step S404 is executed; if yes, it is determined that each area meets the preset overload condition.

[0104] S404: If each area does not meet the preset overload condition, the flexible interconnection device in each area is controlled to be in a shutdown state.

[0105] In one possible implementation, if each area does not meet the preset overload conditions, the flexible interconnection device in each area can be controlled to be in a shutdown state, that is, the energy storage system can operate stably at this time, that is, the power of the charging equipment in each area in operation is stable.

[0106] The embodiment of the present application provides a substation voltage control method, which determines the allowable transfer power of the flexible interconnection device in each substation through the allowable operating power of the flexible interconnection device in each substation and the preset hysteresis power of each substation; then determines the power difference of each substation according to the tripping power threshold of each substation and the preset hysteresis power of each substation; then determines whether each substation meets the preset overload condition according to the power difference of each substation and the real-time charging load power of each substation; if each substation does not meet the preset overload condition, the flexible interconnection device in each substation is controlled to be in a shutdown state, so that the real-time operating power of the charging equipment in each substation is stable, thereby ensuring the stability and quality of the electric energy of each charging station when the charging station is in operation.

[0107] The following is a detailed explanation and description of the substation voltage control method provided in the above embodiment of the present application in conjunction with the accompanying drawings. Figure 5 A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 3 .like Figure 5 As shown, in the above method, determining whether each area meets the preset overload condition according to the power difference of each area and the real-time charging load power of each area may include:

[0108] S501: Determine whether the real-time charging load power of each substation is greater than or equal to the power difference of each substation.

[0109] In a possible implementation, it is determined whether the real-time charging load power Pload_tfx of each area is greater than or equal to the power difference ΔPx of each area. If yes, step S502 is executed; if no, step S503 is executed.

[0110] S502: If it is greater than or equal to the power difference of each substation, it is determined that each substation meets the preset overload condition.

[0111] S503: If it is less than the power difference of each substation, it is determined that each substation does not meet the preset overload condition.

[0112] In one possible implementation, if the real-time charging load power Pload_tfx of each area is greater than or equal to the power difference ΔPx of each area, it is determined that each area meets the preset overload condition. If the real-time charging load power Pload_tfx of each area is less than the power difference ΔPx of each area, it is determined that each area does not meet the preset overload condition, that is, the flexible interconnection device in each area is controlled to be in a shutdown state.

[0113] For example, refer to Figure 1 , based on this, determine whether the A and B areas meet the preset overload conditions. If the A and B areas meet the preset overload conditions, calculate the required transfer power Pneed_FIDx corresponding to the A and B areas; if the A and B areas do not meet the preset overload conditions, control the flexible interconnection devices in the A and B areas to be in the shutdown state.

[0114] The embodiment of the present application provides a substation voltage control method, which determines whether the real-time charging load power of each substation is greater than or equal to the power difference of each substation; if it is greater than or equal to the power difference of each substation, it is determined that each substation meets the preset overload condition; if it is less than the power difference of each substation, it is determined that each substation does not meet the preset overload condition, and the flexible interconnection device in each substation is controlled to be in a shutdown state, so that the real-time operating power of the charging equipment in each substation is stable, thereby ensuring the stability and quality of the electric energy of each charging station when the charging station is in operation.

[0115] The following is a detailed explanation and description of the substation voltage control method provided in the above embodiment of the present application in conjunction with the accompanying drawings. Figure 6 A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 4 .like Figure 6 As shown, the above method may also include:

[0116] S601. If the first substation in each substation meets the preset overload condition, the required transfer power of the first substation is determined according to the tripping power threshold of the first substation, the hysteresis power of the first substation and the real-time charging load power of the first substation.

[0117] In one possible implementation, if the real-time charging load power Pload_tf1 of the first substation among all substations is greater than or equal to the power difference ΔPx of the first substation among all substations, that is, the first substation among all substations meets the preset overload condition, then the required transfer power Pneed_FID1 of the first substation can be determined by the following formula (7) based on the tripping power threshold Prate_tf1 of the first substation, the hysteresis power Pdiff_tf1 of the first substation and the real-time charging load power Pload_tf1 of the first substation.

[0118] Pneed_FID1=(Prate_tf1-Pdiff_tf1)-Pload_tf1 Formula (7)

[0119] According to formula (7), the required transfer power corresponding to each substation is Pneed_FIDx=(Prate_tfx-Pdiff_tfx)-Pload_tfx.

[0120] S602: Determine target power transfer conditions to be satisfied by the first substation and the second substation according to the required power transfer of the first substation and the allowable power transfer of the flexible interconnection device in the second substation.

[0121] In one possible implementation, the target transfer conditions satisfied by the first substation and the second substation are determined based on the relationship between the required transfer power Pneed_FID1 of the first substation calculated in step S601 and the allowed transfer power Pallow_exch_tf2 of the flexible interconnection device in the second substation calculated according to formula (5).

[0122] S603: Determine the set transfer power of the first substation and the set transfer power of the second substation according to the target transfer condition.

[0123] In one possible implementation, the set transfer power Pset_FIDx of the flexible interconnection device of the transferred area is determined according to the target transfer conditions satisfied by the first area and the second area, that is, the set transfer power Pset_FID1 of the first area and the set transfer power Pset_FID2 of the second area are determined.

[0124] It should be noted that after obtaining the demand transfer power Pneed_FIDx corresponding to each substation, the demand transfer power Pneed_FIDx needs to be limited to ensure that when each substation is overloaded, the demand transfer power Pneed_FIDx is within the range of (-Prate_tfx, -Pdiff_tfx), and then the set transfer power Pset_FIDx of each substation is determined according to the target transfer conditions.

[0125] S604: Generate a control signal of the flexible interconnection device in the first area and a control signal of the flexible interconnection device in the second area according to the set transfer power of the first area and the set transfer power of the second area.

[0126] In a possible implementation, according to the set transfer power Pset_FID1 of the first area and the set transfer power Pset_FID2 of the second area, a control signal of the flexible interconnection device in the first area and a control signal of the flexible interconnection device in the second area are generated respectively, so as to issue a power on / off instruction to the flexible interconnection device according to the control signal of the flexible interconnection device in the first area; and issue a power on / off instruction to the flexible interconnection device according to the control signal of the flexible interconnection device in the second area. For example, if the set transfer power Pset_FIDx is 0, a shutdown instruction is issued to the flexible interconnection device to instruct the flexible interconnection device to shut down; otherwise, a power on instruction is issued to the flexible interconnection device to instruct the flexible interconnection device to start up.

[0127] The embodiment of the present application provides a substation voltage control method. If the first substation in each substation meets the preset overload condition, the required transfer power of the first substation is determined according to the trip power threshold of the first substation, the hysteresis power of the first substation and the real-time charging load power of the first substation according to the above formula (7); then, according to the relationship between the required transfer power of the first substation and the allowed transfer power of the flexible interconnection device in the second substation, the target transfer conditions satisfied by the first substation and the second substation are determined; then, according to the target transfer conditions, the set transfer power of the first substation and the set transfer power of the second substation are determined; finally, according to the set transfer power of the first substation and the set transfer power of the second substation, a control signal of the flexible interconnection device in the first substation and a control signal of the flexible interconnection device in the second substation are generated respectively, so as to issue a power on / off instruction to the flexible interconnection device according to the control signal of each substation, so as to instruct the flexible interconnection device to power on and off, thereby ensuring that when the energy storage system is running, multiple transformers and multiple charging devices in each substation can operate stably, thereby ensuring the stability of the real-time operating power of the substation.

[0128] Optionally, in the above method, determining the target transfer conditions satisfied by the first and second substations according to the required transfer power of the first substation and the allowed transfer power of the flexible interconnection device in the second substation may include:

[0129] If the required transfer power of the first substation is less than the allowed transfer power of the flexible interconnection device in the second substation, the target transfer condition is determined to be the first transfer condition.

[0130] In a possible implementation manner, if the demand transfer power Pneed_FID1 of the first substation area is less than the allowable transfer power Pallow_exch_tf2 of the flexible interconnection device in the second substation area, that is, Pneed_FID1 < Pallow_exch_tf2, it indicates that the second substation area has sufficient remaining capacity for transfer. The remaining capacity in the second substation area can be transferred to the first substation area. Then, the target transfer condition is determined as the first transfer condition, that is, the first transfer condition is Pneed_FID1 + Pallow_exch_tf2 > 0.

[0131] In a possible implementation embodiment, according to the target transfer condition, determining the set transfer power of the first substation area and the set transfer power of the second substation area may include:

[0132] Under the first transfer condition, according to the demand transfer power of the first substation area, determine the set transfer power of the first substation area and the set transfer power of the second substation area.

[0133] In a possible implementation manner, under the first transfer condition (such as Pneed_FID1 + Pallow_exch_tf2 > 0), that is, the demand transfer power Pneed_FID1 of the flexible interconnection device in the first substation area (i.e., the substation area to be transferred) is less than the allowable transfer power Pallow_exch_tf2 of the second substation area, it indicates that the second substation area has sufficient remaining capacity for transfer. Then, the set transfer power Pset_FID1 of the first substation area can be determined as the demand transfer power Pneed_FID1 of the first substation area, that is, the set transfer power Pset_FID1 = Pneed_FID1; the set transfer power Pset_FID2 of the second substation area is determined as the set transfer power Pset_FID1 of the first substation area, that is, the set transfer power Pset_FID2 = -(Pset_FID1) = -(Pneed_FID1).

[0134] For the substation area voltage control method provided by the embodiments of the present application, if the demand transfer power of the first substation area is less than the allowable transfer power of the flexible interconnection device in the second substation area, the target transfer condition is determined as the first transfer condition, that is, Pneed_FID1 + Pallow_exch_tf2 > 0, which indicates that the second substation area has sufficient remaining capacity for transfer. Under the first transfer condition, the set transfer power of the first substation area can be determined as the demand transfer power of the first substation area; the set transfer power of the second substation area is determined as the set transfer power of the first substation area, so as to effectively alleviate the problem of power oscillation in each substation area under the first transfer condition.

[0135] The following continues to explain and illustrate in detail the substation area voltage control method provided by the above embodiments of the present application in combination with the accompanying drawings. Figure 7A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 5 .like Figure 7 As shown, in the above method, according to the required transfer power of the first substation and the allowed transfer power of the flexible interconnection device in the second substation, determining the target transfer conditions satisfied by the first substation and the second substation may include:

[0136] S701: If the required transfer power of the first substation is greater than or equal to the allowed transfer power of the flexible interconnection device in the second substation, determine whether the allowed transfer power of the flexible interconnection device in the second substation exceeds a preset multiple of the hysteresis power of the first substation.

[0137] The preset multiple N can be set empirically based on actual conditions. Generally, the preset multiple N is 2. N is a positive integer greater than 1.

[0138] In one possible implementation, if the required transfer power Pneed_FID1 of the first substation is greater than or equal to the allowed transfer power Pallow_exch_tf2 of the flexible interconnection device in the second substation, that is, Pneed_FID1≥Pallow_exch_tf2, it is necessary to determine whether the allowed transfer power Pallow_exch_tf2 of the flexible interconnection device in the second substation exceeds a preset multiple of the hysteresis power of the first substation (such as 2*Pdiff_tf1), that is, determine whether Pallow_exch_tf2≥2*Pdiff_tf1 is satisfied.

[0139] S702: If the allowable transfer power of the flexible interconnection device in the second substation exceeds a preset multiple of the hysteresis power of the first substation, determine the target transfer condition to be the second transfer condition.

[0140] In one possible implementation, if the allowable transfer power Pallow_exch_tf2 of the flexible interconnect device in the second substation exceeds a preset multiple of the hysteresis power of the first substation (such as 2*Pdiff_tf1), that is, Pallow_exch_tf2≥2*Pdiff_tf1, then the target transfer condition is determined to be the second transfer condition, that is, the second transfer condition is Pallow_exch_tf2≥2*Pdiff_tf1.

[0141] Optionally, determining the set transfer power of the first substation and the set transfer power of the second substation according to the target transfer condition may include:

[0142] Under the second transfer condition, the set transfer power of the first substation and the set transfer power of the second substation are determined according to the difference between the allowable transfer power of the flexible interconnection device in the second substation and the hysteresis power of the second substation.

[0143] In one possible implementation, under the second transfer condition (such as Pallow_exch_tf2≥2*Pdiff_tf1), it means that although the allowable transfer power Pallow_exch_tf2 of the flexible interconnection device in the second area is not enough to meet all power requirements of the first area (i.e., the area being transferred), there is still some capacity in the second area that can be transferred. Therefore, under the condition that the second area does not exceed the light load power value of the first area (i.e., Prate_tf1-pdiff_tf1), the transfer power is partial to ensure the total charging operation power of the first area. The difference between the allowable transfer power Pallow_exch_tf2 of the flexible interconnection device in the second area and the hysteresis power Pdiff_tf2 of the second area can be used. , that is (Pallow_exch_tf2-Pdiff_tf2), determine the set transfer power Pset_FID1 of the first substation and the set transfer power Pset_FID2 of the second substation, that is, the set transfer power Pset_FID1 of the first substation (that is, the substation to be transferred) is (-(Pallow_exch_tf2-Pdiff_tf2)), that is, Pset_FID1=(-(Pallow_exch_tf2-Pdiff_tf2)), the set transfer power Pset_FID2 of the second substation is Pset_FID1, that is, Pset_FID2=-(Pset_FID1)=(Pallow_exch_tf2)-(Pdiff_tf2).

[0144] The embodiment of the present application provides a substation voltage control method. If the required transfer power of the first substation is greater than or equal to the allowed transfer power of the flexible interconnection device in the second substation, it can be determined whether the allowed transfer power of the flexible interconnection device in the second substation exceeds the preset multiple of the hysteresis power of the first substation; if the allowed transfer power of the flexible interconnection device in the second substation exceeds the preset multiple of the hysteresis power of the first substation, the target transfer condition is determined to be the second transfer condition; then under the second transfer condition, the set transfer power of the first substation and the set transfer power of the second substation are determined according to the difference between the allowed transfer power of the flexible interconnection device in the second substation and the hysteresis power of the second substation, so as to effectively alleviate the problem of power oscillation in each substation under the second transfer condition.

[0145] Optionally, the method may further include determining the target transfer conditions satisfied by the first and second substations according to the required transfer power of the first substation and the allowed transfer power of the flexible interconnection device in the second substation, and may further include:

[0146] If the allowable transfer power of the flexible interconnection device in the second area is less than the preset multiple of the hysteresis power of the first area, but greater than or equal to the hysteresis power of the first area, the target transfer condition is determined to be the third transfer condition.

[0147] In one possible implementation, if the allowable transfer power Pallow_exch_tf2 of the flexible interconnection device in the second substation is less than a preset multiple of the hysteresis power of the first substation (such as 2*Pdiff_tf1), that is, Pallow_exch_tf2<2*Pdiff_tf1, and the allowable transfer power Pallow_exch_tf2 of the flexible interconnection device in the second substation is greater than or equal to the hysteresis power Pdiff_tf1 of the first substation, that is, Pallow_exch_tf2≥Pdiff_tf1, then the target transfer condition can be determined as the third transfer condition, that is, the third transfer condition is (Pallow_exch_tfy<2*Pdiff_tfx)&&(Pallow_exch_tfy≥Pdiff_tfx).

[0148] In a possible implementation, determining the set transfer power of the first substation and the set transfer power of the second substation according to the target transfer condition may include:

[0149] Under the third transfer condition, the set transfer power of the first substation and the set transfer power of the second substation are determined according to the allowable transfer power of the flexible interconnection device in the second substation.

[0150] In a possible implementation, under the third transfer condition (such as (Pallow_exch_tfy<2*Pdiff_tfx)&&(Pallow_exch_tfy≥Pdiff_tfx)), the set transfer power Pset_FID1 of the first area and the set transfer power Pset_FID2 of the second area can be determined according to the allowed transfer power Pallow_exch_tf2 of the flexible interconnection device in the second area. That is, the set transfer power Pset_FID1 of the first area is Pallow_exch_tf2, that is, Pset_FID1=-(Pallow_exch_tf2), and the set transfer power Pset_FID2 of the second area is Pset_FID1, that is, Pset_FID2=-(-(Pallow_exch_tf2))=Pallow_exch_tf2.

[0151] It should be noted that when the first transfer condition, the second transfer condition and the third transfer condition are not met, the set transfer power Pset_FID1 of the transferred area (i.e., the first area) is 0. It is worth noting that after calculating the set transfer power Pset_FID1 of the transferred area (i.e., the first area), the set transfer power Pset_FID2 of the second area of ​​the area to be transferred (i.e., the second area) is (-Pset_FID1).

[0152] In the substation voltage control method provided by the embodiment of the present application, if the allowable transfer power of the flexible interconnection device in the second substation is less than a preset multiple of the hysteresis power of the first substation, and the allowable transfer power of the flexible interconnection device in the second substation is greater than or equal to the hysteresis power of the first substation, then the target transfer condition can be determined to be a third transfer condition; and under the third transfer condition, the set transfer power of the first substation and the set transfer power of the second substation are determined according to the allowable transfer power of the flexible interconnection device in the second substation, so as to effectively alleviate the problem of power oscillation in each substation under the third transfer condition.

[0153] The following is a detailed explanation and description of the substation voltage control method provided in the above embodiment of the present application in conjunction with the accompanying drawings. Figure 8 A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 6 .like Figure 8 As shown, in the above method, adjusting the real-time operating power of the charging equipment in each area according to the allowed operating power of the flexible interconnection device in each area and the second real-time operating power of each area may include:

[0154] S801. Update the limited operating power of the charging equipment in each area according to the allowed operating power of the flexible interconnection device in each area and the second real-time operating power of each area.

[0155] In one possible implementation, the operating rated power of all charging equipment configured in each substation is used as the maximum initial limit. The operating rated power of all charging equipment in the substation can be understood as the tripping power threshold of each substation (such as 535.5KVA). When the energy storage system is running, the limit operating power Pset_chg_tfx of the charging equipment in each substation can be updated separately according to the allowable operating power Pallow_exch_tfx of the flexible interconnection device in each substation and the second real-time operating power Prun_FIDx of each substation.

[0156] Among them, Pset_chg_tfx is the limited operating power of each charging device in the station area x.

[0157] For example, the limited operating power Pset_chg_tfx of the charging equipment in each area can be updated according to the following formula (8).

[0158] Pset_chg_tfx=Prun_chg_tfx+Pallow_tfx-Prun_FIDx Formula (8)

[0159] Wherein, Prun_chg_tfx is the historical operating power of each charging device in the station area x in the previous calculation cycle.

[0160] S802: Take the smaller of the limited operating power of the charging equipment in each area and the rated operating power of the corresponding charging equipment to obtain the real-time operating power of the charging equipment in each area.

[0161] In one possible implementation, the real-time operating power Prun_chg of the charging equipment in each area can be obtained by taking the smaller of the limiting operating power Pset_chg_tfx of the charging equipment in each area and the rated operating power (such as 535.5KVA) of the corresponding charging equipment.

[0162] It should be noted that, as a finite element device, the flexible interconnection device has a maximum transferable power limit to limit the transfer power of the flexible interconnection device before it is sent. In addition, it should be noted that during real-time operation, according to the tripping power threshold of the transformer in each area and the real-time charging load power of all charging devices, only the real-time operating power limit of some charging devices can be updated in real time as needed.

[0163] The embodiment of the present application provides a method for controlling the voltage of a substation, which updates the limited operating power of the charging equipment in each substation according to the allowed operating power of the flexible interconnection device in each substation and the second real-time operating power of each substation; and performs a smaller operation on the limited operating power of the charging equipment in each substation and the rated operating power of the corresponding charging equipment to obtain the real-time operating power of the charging equipment in each substation, so as to limit the real-time operating power of the charging equipment in each substation in combination with the result of setting the transfer power of the flexible interconnection device in each substation, and update the actual operating power of each charging equipment according to the limit value, so as to give priority to calling the set transfer power of the flexible interconnection device on the basis of ensuring the real-time operating power of each charging equipment, and when the transfer power is not satisfied, the real-time operating total power of each substation is adjusted by adjusting the real-time operating power limit of each charging device to ensure that the real-time operating total power of multiple substations does not exceed the limit, so as to solve the problem of large fluctuations in the substation operating power due to sudden increase or decrease in charging power when the existing flexible substation transfer strategy is applied to the charging station.

[0164] To facilitate understanding of the above-mentioned substation voltage control method, the present application embodiment further provides an example of a process of the substation voltage control method, which is described below in conjunction with the accompanying drawings. Fig. 9 A schematic diagram of a method for controlling a voltage in a station area provided in an embodiment of the present application Figure 7 .like Fig. 9 As shown, the station area voltage control method may include:

[0165] S901. Determine the real-time total charging load power of each substation according to the first real-time operating power of each substation and the second real-time operating power of each substation.

[0166] Specifically, the first real-time operating power Prun_tfx of the transformer corresponding to the X substations and the second real-time operating power Prun_FIDx of the corresponding flexible interconnection device are obtained, and the real-time total charging load power Pload_tfx of the charging stations in the X substations is calculated by the above formula (1).

[0167] S902: Determine the allowable operating power of the flexible interconnection device in each substation according to the tripping power threshold of each substation and the real-time charging load power of each substation.

[0168] Specifically, after obtaining the real-time charging load power Pload_tfx of each substation, the allowable operating power Pallow_tfx of the flexible interconnection device in each substation can be determined by the above formula (3) according to the tripping power threshold Prate_tfx (such as 535.5KVA) of the transformer in each substation.

[0169] S903: Determine the allowable transfer power of the flexible interconnection device in each substation according to the allowable operating power of the flexible interconnection device in each substation and the preset hysteresis power of each substation.

[0170] Specifically, according to the allowable operating power Pallow_tfx of the flexible interconnection device in each substation and the preset hysteresis power Pdiff_tfx (such as 31.5KVA) of each substation, the allowable transfer power Pallow_exch_tfx of the flexible interconnection device in each substation is determined by the above formula (5).

[0171] S904: Send down the setting transfer power of the flexible interconnection device in each substation.

[0172] Specifically, first, based on the difference between the trip power threshold Prate_tfx (such as 535.5KVA) of the transformer of each substation and the preset hysteresis power Pdiff_tfx (such as 31.5KVA) and the real-time total charging load power Pload_tfx of each substation, Pload_tfx≥(Prate_tfx)-(Pdiff_tfx) is used to determine whether each substation meets the preset overload condition. Then, it is determined in turn whether the first substation and the second substation meet the preset overload condition. If the first substation and the second substation meet the preset overload condition, the transfer power calculation process of the flexible interconnection device of the substation overload is entered; if the first substation and the second substation do not meet the preset overload condition, the set transfer power Pset_FID1 of the first substation and the set transfer power Pset_FID2 of the second substation are directly issued as 0 to instruct the flexible interconnection device to shut down.

[0173] Furthermore, the calculation process of the setting transfer power of the flexible interconnection device in the overloaded area is as follows:

[0174] If the first substation in each substation meets the preset overload condition, the required transfer power Pneed_FID1 of the first substation is determined by the above formula (7) according to the trip power threshold Prate_tf1 of the first substation, the hysteresis power Pdiff_tf1 of the first substation and the real-time charging load power Pload_tf1 of the first substation, and then the required transfer power Pneed_FID1 is limited. When the first substation is overloaded, the required transfer power Pneed_FID1 should be within the range of (-Prate_tf1, -Pdiff_tf1); then the set transfer power of the corresponding flexible interconnection device is output according to the target transfer condition. Rate, that is, if the first transfer condition is met (such as Pneed_FID1+Pallow_exch_tf2>0), that is, the required transfer power Pneed_FID1 of the flexible interconnection device in the first substation (the substation to be transferred) is less than the allowed transfer power Pallow_exch_tf2 of the second substation, it means that the second substation has sufficient remaining capacity for transfer, then the set transfer power Pset_FID1 of the flexible interconnection device in the first substation (the substation to be transferred) is the required transfer power Pneed_FID1, and the set transfer power Pset_FID2 of the second substation is the set transfer power Pset_FID1 of the first substation.

[0175] Otherwise, determine whether the allowed transfer power Pallow_exch_tf2 of the second area exceeds 2 times the preset multiple of the hysteresis power of the first area (i.e., the second transfer condition = Pallow_exch_tf2≥2*Pdiff_tf1). This means that although the allowed transfer power Pallow_exch_tf2 cannot meet the power requirements of all the areas to be transferred, there is still some capacity that can be transferred in the second area. Therefore, at this time, part of the power is transferred under the condition that the first area does not exceed the light load power value (i.e., Prate_tfx-pdiff_tfx) to ensure the total charging operating power of the first area. In this case, the set transfer power Pset_FID1 of the first area is (-(Pallow_exch_tfy-Pdiff_tfy)), and the set transfer power Pset_FID2 of the second area is Pallow_exch_tf2-Pdiff_tf2.

[0176] In addition, if the third transfer condition is met (ie, Pallow_exch_tfy<2*Pdiff_tfx&&Pallow_exch_tfy≥Pdiff_tfx), the set transfer power Pset_FID1 of the first substation (ie, the transferred substation) is Pallow_exch_tf2; the set transfer power Pset_FID2 of the second substation is also Pallow_exch_tf2.

[0177] It is worth noting that after calculating the set transfer power Pset_FID1 of the transferred area (ie, the first area), the set transfer power Pset_FID2 of the second area of ​​the area to be transferred (ie, the second area) is (-Pset_FID1).

[0178] S905. Update the operating power limit of the charging equipment in each substation.

[0179] Specifically, the limited operating power Pset_chg_tfx of the charging equipment in each substation can be updated according to the above formula (8). Then, the operating rated power of all charging equipment configured in each substation is used as the maximum initial limit. The operating rated power of all charging equipment in the substation can be understood as the tripping power threshold of each substation (such as 535.5KVA). When the energy storage system is running, the limited operating power Pset_chg_tfx of the charging equipment in each substation can be updated according to the allowed operating power Pallow_exch_tfx of the flexible interconnection device in each substation and the second real-time operating power Prun_FIDx of each substation. The real-time operating power Prun_chg of the charging equipment in each substation can be obtained by combining the limited operating power Pset_chg_tfx of the charging equipment in each substation and the rated operating power (such as 535.5KVA) of the corresponding charging equipment.

[0180] For example, area A contains three charging devices, and the maximum operating limit powers of these three charging devices are 480KVA, 120KVA and 120KVA respectively; area B contains four charging devices, and the maximum operating limit powers of these four charging devices are 360KVA, 120KVA, 120KVA and 120KVA respectively. The rated power of the transformers in area A and area B is 630KVA; the tripping power threshold Prate_tfx of area A and area B is: 630KVA*0.85=535.5KVA; the preset hysteresis power Pdiff_tfx is: 630KVA*0.05=31.5KVA.

[0181] Table 1 below is a data table showing the real-time operating power of the charging equipment, the set transfer power of the flexible interconnection device, and other sampled power changes when the load of area A suddenly increases by 50 at the 5th second.

[0182]

[0183]

[0184] As can be seen from Table 1 above, when all charging devices in any area are charged at full power at the same time, the corresponding area will trip; when the flexible interconnection device is used to expand the rechargeable capacity in Area A and Area B, the real-time operating power Prun_chg of the charging equipment that limits the maximum charging power of each area can be used. That is, Area A updates the real-time operating power Prun_chg of the charging equipment with a maximum operating limit power of 480KVA in real time, and Area B updates the real-time operating power Prun_chg of the charging equipment with a maximum operating limit power of 360KVA in real time.

[0185] The embodiment of the present application provides a method for controlling the voltage of a substation, which determines the real-time total charging load power of each substation according to the first real-time operating power of each substation and the second real-time operating power of each substation; determines the allowable operating power of the flexible interconnection device in each substation according to the tripping power threshold of each substation and the real-time charging load power of each substation; determines the allowable transfer power of the flexible interconnection device in each substation according to the allowable operating power of the flexible interconnection device in each substation and the preset hysteresis power of each substation; issues the set transfer power of the flexible interconnection device in each substation; updates the limit operating power of the charging equipment in each substation, so as to On the basis of ensuring the real-time operating power of the charging equipment in each area, the set transfer power of the flexible station interconnection device is preferentially called. When the set transfer power of the flexible station interconnection device is not met, the maximum operating limit power of the charging equipment in each area is adjusted to adjust the real-time operating power of the charging equipment in each area to ensure that the real-time operating power of each area does not exceed the limit. This solves the problem of large fluctuations in the real-time operating power of each area caused by the sudden increase or decrease in the real-time operating power of the charging equipment in each area when the existing flexible station transfer strategy is applied to the charging station. At the same time, when the energy storage equipment is running, the stability and quality of the electric energy can be further guaranteed.

[0186] Based on the same inventive concept, a substation voltage control device is also provided in the embodiment of the present application. Since the principle of solving the problem by the device in the embodiment of the present application is similar to the above-mentioned substation voltage control method in the embodiment of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0187] Fig.10 This is a schematic diagram of the structure of a station area voltage control device provided in an embodiment of the present application. Fig.10 As shown, the station area voltage control device 1000 may include:

[0188] The first determination module 1001 is used to determine the real-time total charging load power of each substation according to the first real-time operating power of each substation and the second real-time operating power of each substation, wherein the first real-time operating power is the real-time operating power of the transformer in each substation, the second real-time operating power is the real-time operating power of the flexible interconnection device in each substation, and the real-time total charging load power is the real-time charging load power of all charging devices in each substation;

[0189] The second determination module 1002 is used to determine the allowable operating power of the flexible interconnection device in each substation according to the trip power threshold of each substation and the real-time charging load power of each substation;

[0190] The adjustment module 1003 is used to adjust the real-time operating power of the charging equipment in each substation according to the allowed operating power of the flexible interconnection device in each substation and the second real-time operating power of each substation, so that the first real-time operating power of each substation after adjustment does not exceed the tripping power threshold of each substation.

[0191] In an optional embodiment, the substation voltage control device 1000 is also used to: determine the allowable transfer power of the flexible interconnection device in each substation according to the allowable operating power of the flexible interconnection device in each substation and the preset hysteresis power of each substation; determine the power difference of each substation according to the tripping power threshold of each substation and the preset hysteresis power of each substation; determine whether each substation meets the preset overload condition according to the power difference of each substation and the real-time charging load power of each substation; if each substation does not meet the preset overload condition, control the flexible interconnection device in each substation to be in a shutdown state.

[0192] In an optional embodiment, the substation voltage control device 1000 is specifically used to: determine whether the real-time charging load power of each substation is greater than or equal to the power difference of each substation; if it is greater than or equal to the power difference of each substation, determine that each substation meets the preset overload condition; if it is less than the power difference of each substation, determine that each substation does not meet the preset overload condition.

[0193] In an optional embodiment, the substation voltage control device 1000 is also used for: if the first substation among the substations meets the preset overload condition, determining the required transfer power of the first substation according to the tripping power threshold of the first substation, the hysteresis power of the first substation and the real-time charging load power of the first substation; determining the target transfer conditions satisfied by the first substation and the second substation according to the required transfer power of the first substation and the allowed transfer power of the flexible interconnection device in the second substation; determining the set transfer power of the first substation and the set transfer power of the second substation according to the target transfer conditions; and generating a control signal of the flexible interconnection device in the first substation and a control signal of the flexible interconnection device in the second substation, respectively, according to the set transfer power of the first substation and the set transfer power of the second substation.

[0194] In an optional implementation, the substation voltage control device 1000 is specifically used to: if the required transfer power of the first substation is less than the allowed transfer power of the flexible interconnection device in the second substation, determine the target transfer condition to be the first transfer condition.

[0195] In an optional implementation, the substation voltage control device 1000 is specifically used to: under the first transfer condition, according to the required transfer power of the first substation, determine the set transfer power of the first substation and the set transfer power of the second substation.

[0196] In an optional embodiment, the substation voltage control device 1000 is specifically used to: if the required transfer power of the first substation is greater than or equal to the allowable transfer power of the flexible interconnection device in the second substation, determine whether the allowable transfer power of the flexible interconnection device in the second substation exceeds a preset multiple of the hysteresis power of the first substation; if the allowable transfer power of the flexible interconnection device in the second substation exceeds the preset multiple of the hysteresis power of the first substation, determine that the target transfer condition is the second transfer condition.

[0197] In an optional embodiment, the substation voltage control device 1000 is specifically used to: under the second transfer condition, determine the set transfer power of the first substation and the set transfer power of the second substation based on the difference between the allowable transfer power of the flexible interconnection device in the second substation and the hysteresis power of the second substation.

[0198] In an optional embodiment, the substation voltage control device 1000 is specifically used to: if the allowable transfer power of the flexible interconnection device in the second substation is less than a preset multiple of the hysteresis power of the first substation, but greater than or equal to the hysteresis power of the first substation, then determine the target transfer condition to be the third transfer condition.

[0199] In an optional implementation, the substation voltage control device 1000 is specifically used to: under the third transfer condition, determine the set transfer power of the first substation and the set transfer power of the second substation according to the allowed transfer power of the flexible interconnection device in the second substation.

[0200] In an optional implementation, the adjustment module 1003 is specifically configured to:

[0201] According to the allowed operating power of the flexible interconnection device in each area and the second real-time operating power of each area, the limited operating power of the charging equipment in each area is updated respectively;

[0202] The smaller of the limit operating power of the charging equipment in each area and the rated operating power of the corresponding charging equipment is taken to obtain the real-time operating power of the charging equipment in each area.

[0203] It should be noted that for details not disclosed in the substation voltage control device of the embodiment of the present application, please refer to the details disclosed in the substation voltage control method of the embodiment of the present application, and the details will not be repeated here.

[0204] The above modules may be one or more integrated circuits configured to implement the above methods, such as one or more application specific integrated circuits (ASICs), or one or more microprocessors, or one or more field programmable gate arrays (FPGAs). For another example, when a module is implemented in the form of a processing element scheduling program code, the processing element may be a general-purpose processor, such as a central processing unit (CPU) or other processor that can call program code. For another example, these modules may be integrated together and implemented in the form of a system-on-a-chip (SOC).

[0205] Optionally, the embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the processor executes the steps of the station area voltage control method of the mobile storage medium in the above embodiment. The specific implementation method and technical effect are similar and will not be repeated here.

[0206] In the several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0207] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0208] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0209] The above-mentioned integrated unit implemented in the form of a software functional unit can be stored in a computer-readable storage medium. The above-mentioned software functional unit is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor (English: processor) to perform some steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (English: Read-Only Memory, abbreviated: ROM), random access memory (English: Random Access Memory, abbreviated: RAM), disk or optical disk and other media that can store program codes.

[0210] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for controlling a voltage in a station area, characterized in that: include: Determine the real-time total charging load power of each substation according to the first real-time operating power of each substation and the second real-time operating power of each substation, wherein the first real-time operating power is the real-time operating power of the transformer in each substation, the second real-time operating power is the real-time operating power of the flexible interconnection device in each substation, and the real-time total charging load power is the real-time charging load power of all charging devices in each substation; Determine the allowable operating power of the flexible interconnection device in each substation according to the trip power threshold of each substation and the real-time charging load power of each substation; According to the allowed operating power of the flexible interconnection device in each substation and the second real-time operating power of each substation, the real-time operating power of the charging equipment in each substation is adjusted so that the first real-time operating power of each substation after adjustment does not exceed the tripping power threshold of each substation.

2. The method for controlling the voltage in a substation according to claim 1, characterized in that: The method further comprises: Determine the allowable transfer power of the flexible interconnection device in each area according to the allowable operating power of the flexible interconnection device in each area and the preset hysteresis power of each area; Determine the power difference of each substation according to the trip power threshold of each substation and the preset hysteresis power of each substation; Determine whether each of the stations meets a preset overload condition according to the power difference of each of the stations and the real-time charging load power of each of the stations; If the preset overload condition is not satisfied in each of the sections, the flexible interconnection devices in each section are controlled to be in a shutdown state.

3. The method for controlling the voltage in a metro station according to claim 2, characterized in that: The determining whether each of the stations meets the preset overload condition according to the power difference of each of the stations and the real-time charging load power of each of the stations includes: Determine whether the real-time charging load power of each of the stations is greater than or equal to the power difference of each of the stations; If it is greater than or equal to the power difference of each of the substations, it is determined that each of the substations meets the preset overload condition; If it is less than the power difference of each of the stations, it is determined that each of the stations does not meet the preset overload condition.

4. The method for controlling the voltage in a metro station according to claim 3, characterized in that: The method further comprises: If the first substation among the substations meets the preset overload condition, the required transfer power of the first substation is determined according to the trip power threshold of the first substation, the hysteresis power of the first substation and the real-time charging load power of the first substation; Determine target transfer conditions satisfied by the first substation and the second substation according to the required transfer power of the first substation and the allowable transfer power of the flexible interconnection device in the second substation; According to the target power transfer condition, determining the set power transfer of the first substation and the set power transfer of the second substation; According to the set transfer power of the first area and the set transfer power of the second area, a control signal of the flexible interconnection device in the first area and a control signal of the flexible interconnection device in the second area are generated respectively.

5. The method for controlling the voltage in a metropolitan area according to claim 4, characterized in that: The determining, according to the required transfer power of the first substation and the allowed transfer power of the flexible interconnection device in the second substation, the target transfer conditions satisfied by the first substation and the second substation include: If the required transfer power of the first area is less than the allowed transfer power of the flexible interconnection device in the second area, determining the target transfer condition to be the first transfer condition; The step of determining the set transfer power of the first area and the set transfer power of the second area according to the target transfer condition includes: Under the first transfer condition, the set transfer power of the first substation and the set transfer power of the second substation are determined according to the required transfer power of the first substation.

6. The method for controlling the voltage in a metro station according to claim 4, characterized in that: The determining, according to the required transfer power of the first substation and the allowed transfer power of the flexible interconnection device in the second substation, the target transfer conditions satisfied by the first substation and the second substation include: If the required transfer power of the first area is greater than or equal to the allowed transfer power of the flexible interconnection device in the second area, determine whether the allowed transfer power of the flexible interconnection device in the second area exceeds a preset multiple of the hysteresis power of the first area; If the allowable transfer power of the flexible interconnection device in the second station area exceeds the preset multiple of the hysteresis power of the first station area, determining the target transfer condition to be the second transfer condition; The step of determining the set transfer power of the first area and the set transfer power of the second area according to the target transfer condition includes: Under the second transfer condition, the set transfer power of the first area and the set transfer power of the second area are determined according to the difference between the allowed transfer power of the flexible interconnection device in the second area and the hysteresis power of the second area.

7. The method for controlling the voltage in a metro station according to claim 6, characterized in that: The step of determining target transfer conditions satisfied by the first and second substations according to the required transfer power of the first substation and the allowed transfer power of the flexible interconnection device in the second substation also includes: If the allowable transfer power of the flexible interconnection device in the second station area is less than the preset multiple of the hysteresis power of the first station area, but greater than or equal to the hysteresis power of the first station area, then determining that the target transfer condition is the third transfer condition; The step of determining the set transfer power of the first area and the set transfer power of the second area according to the target transfer condition includes: Under the third transfer condition, the set transfer power of the first substation and the set transfer power of the second substation are determined according to the allowed transfer power of the flexible interconnection device in the second substation.

8. The method for controlling the voltage in a metro station according to claim 1, characterized in that: The adjusting the real-time operating power of the charging equipment in each area according to the allowed operating power of the flexible interconnection device in each area and the second real-time operating power of each area includes: According to the allowed operating power of the flexible interconnection device in each area and the second real-time operating power of each area, respectively updating the limited operating power of the charging equipment under each area; The smaller of the limited operating power of the charging equipment in each area and the rated operating power of the corresponding charging equipment is taken to obtain the real-time operating power of the charging equipment in each area.

9. A control device, characterized in that: The control device includes: a processor; and a memory communicatively connected to the processor; wherein the memory stores a computer program executable by the processor, and the computer program is executed by the processor so that the processor can execute the substation voltage control method described in any one of claims 1-8.

10. An energy storage system, characterized in that: The energy storage system comprises: transformers in multiple substations, multiple charging devices, multiple flexible interconnection devices, and the control device described in claim 9; Among them, the transformers in the multiple substations are respectively connected to the flexible interconnection devices in their respective substations, and the transformers in the multiple substations are respectively connected to the charging equipment in their respective substations; the control device is communicatively connected with the transformers in the multiple substations, the multiple flexible interconnection devices and the multiple charging equipment; the control device is used to execute the substation voltage control method described in any one of claims 1-8.

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