Transformer area interconnection system

Abstract

The utility model provides a transformer area interconnection system, and relates to the technical field of power electronics. The transformer area interconnection system comprises a plurality of flexible transformer area interconnection devices, each flexible transformer area interconnection device comprises a plurality of current transformation modules, and the alternating current sides of the plurality of current transformation modules in each flexible transformer area interconnection device are connected with a transformer of the same transformer area; the direct current sides of the plurality of converter modules in the first flexible transformer area interconnection device in the plurality of flexible transformer area interconnection devices are respectively connected with the direct current sides of the plurality of converter modules in the second flexible transformer area interconnection device, so as to form a plurality of groups of parallel power channels between the first flexible transformer area interconnection device and the second flexible transformer area interconnection device. Therefore, according to the application, when the fault of any current conversion module is received, the shutdown command is only issued to the fault current conversion module, and the transformer area interconnection system can work normally.

Description

Technical Field

[0001] The present application relates to the field of power electronics technology, and in particular to a substation interconnection system. Background Art

[0002] In a dual-zone interconnection scenario, multiple converter modules are connected in parallel to the zone interconnection system. Multiple converter modules communicate with each other through parallel cables, using a master-multiple slave mode, that is, each slave aggregates the data stream to the master module, and the master module interacts with the control device in the zone interconnection system; when the zone interconnection system issues the working mode and operating parameters to each converter module, the zone interconnection system first issues the instructions to the master module in each converter module, and then the master module issues the instructions to all slave modules in each converter module. When starting up, the master module confirms the status of all converter modules. After confirming that there are no faults, all converter modules are started up at the same time. When any converter module fails, it is reported to the master module in a unified manner. The master module issues a shutdown command to all converter modules and sends the fault to the zone interconnection system.

[0003] However, in this case, when the host module receives a message that any converter module has a fault, it will send a shutdown command to all converter modules, causing the converter modules without faults to shut down and become unable to work. Utility Model Content

[0004] The purpose of this application is to provide a substation interconnection system that can, when receiving a fault in any converter module, only issue a shutdown command to the faulty converter module without affecting the operation of other non-faulty converter modules in the same substation.

[0005] To achieve the above objectives, the technical solutions adopted in the embodiments of the present application are as follows:

[0006] In a first aspect, an embodiment of the present application provides a substation interconnection system, comprising: a plurality of flexible substation interconnection devices, wherein each flexible substation interconnection device comprises: a plurality of converter modules, wherein the AC sides of the plurality of converter modules in each flexible substation interconnection device are all connected to a transformer in the same substation;

[0007] The DC sides of the multiple converter modules in the first flexible metro area interconnection device among the multiple flexible metro area interconnection devices are respectively connected to the DC sides of the multiple converter modules in the second flexible metro area interconnection device to form multiple groups of parallel power channels between the first flexible metro area interconnection device and the second flexible metro area interconnection device.

[0008] Optionally, the DC sides of the multiple converter modules in the first flexible metropolitan area interconnection device are connected to the DC sides of the multiple converter modules in the second flexible metropolitan area interconnection device in a one-to-one correspondence to form the multiple groups of parallel power channels.

[0009] Optionally, the DC side of a converter module in the first flexible metropolitan area interconnection device is connected to the DC sides of some or all converter modules in the second flexible metropolitan area interconnection device to form the multiple groups of parallel power channels.

[0010] Optionally, the substation interconnection system further includes: a control device; each flexible substation interconnection device further includes: a control unit, the control unit is connected to the multiple converter modules in parallel, and the control unit is connected to the control device.

[0011] Optionally, the substation interconnection system also includes: multiple energy storage modules, and the DC sides of the multiple conversion modules in the first flexible substation interconnection device are respectively connected to the DC sides of the multiple conversion modules in the second flexible substation interconnection device through the multiple energy storage modules to form multiple groups of energy storage and conversion channels between the first flexible substation interconnection device and the second flexible substation interconnection device.

[0012] In a second aspect, an embodiment of the present application provides a substation interconnection system, comprising: a plurality of groups of flexible substation interconnection devices, wherein each group of flexible substation interconnection devices comprises: a plurality of flexible interconnection devices, each flexible interconnection device comprises: a converter module;

[0013] The AC sides of the converter modules of the multiple flexible interconnection devices in each group are respectively connected to the transformers of the corresponding substations, and the DC sides of the converter modules of the multiple flexible interconnection devices in each group are connected in parallel.

[0014] Optionally, the number of the converter modules in each flexible interconnection device is one or more.

[0015] Optionally, each group further includes: an energy storage module, and the DC ends of the converter modules of the multiple flexible interconnection devices in each group are electrically connected to the energy storage module in parallel.

[0016] Optionally, the substation interconnection system further includes: a control device; each of the flexible interconnection devices further includes: a control unit, the control unit being connected to the conversion module;

[0017] Each control unit in the plurality of flexible interconnection devices in each group is connected in parallel to the control device.

[0018] Optionally, each control unit is connected to the control device via a wired Ethernet communication line, or each control unit is connected to the control device via wireless Ethernet communication.

[0019] The beneficial effects of the area interconnection system provided by this application are:

[0020] The present application provides a substation interconnection system, which is composed of multiple flexible substation interconnection devices, wherein each flexible substation interconnection device includes: multiple converter modules, the AC sides of the multiple converter modules in each flexible substation interconnection device are connected to the transformer of the same substation, so that the multiple converter modules in each flexible substation interconnection device are powered by the transformer of the same substation; the DC sides of the multiple converter modules in the first flexible substation interconnection device in the multiple flexible substation interconnection devices are respectively connected to the DC sides of the multiple converter modules in the second flexible substation interconnection device, so as to form multiple groups of parallel power channels between the first flexible substation interconnection device and the second flexible substation interconnection device, so that after a converter module in the multiple converter modules fails, the other converter modules in the multiple converter modules in the substation interconnection system that are not at fault can perform normal data exchange. Therefore, the substation interconnection system provided by the present application can, when any converter module fails, only issue a shutdown command to the failed converter module, without affecting the operation of other converter modules in the same substation. That is, the substation interconnection system can operate normally, thereby improving the reliability of the substation interconnection system. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. 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 relevant drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 1 ;

[0023] Figure 2 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 2 ;

[0024] Figure 3 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 3 ;

[0025] Figure 4 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 4 ;

[0026] Figure 5 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 5 ;

[0027] Figure 6 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 6 ;

[0028] Figure 7 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 7 ;

[0029] Figure 8 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 8 ;

[0030] Figure 9 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 9 ;

[0031] Figure 10 A flowchart of a power reallocation method provided in an embodiment of the present application. DETAILED DESCRIPTION

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0033] 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 protection, but merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in the present application without making any creative efforts shall fall within the scope of protection of the present application.

[0034] 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, it does not need to be further defined or explained in subsequent drawings.

[0035] In the description of this application, it should be understood that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the utility model product is conventionally placed when in use, or are the orientations or positional relationships conventionally understood by those skilled in the art. They are only for the convenience of describing this application and simplifying the description, and do 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 should not be understood as a limitation on this application.

[0036] Furthermore, the terms “first,” “second,” “third,” etc., are merely used for distinguishing descriptions and are not to be understood as indicating or implying relative importance.

[0037] It should also be noted that, in the description of this application, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0038] In order to better understand the various solutions provided in the embodiments of the present application, a substation interconnection system provided in the embodiments of the present application is described in detail below in conjunction with the accompanying drawings.

[0039] Figure 1 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 1 .like Figure 1 As shown, the platform interconnection system 200 may include: a plurality of flexible platform interconnection devices 100 .

[0040] Each flexible platform interconnection device 100 may include: a plurality of converter modules 110 .

[0041] The AC sides of the multiple converter modules 110 in each flexible metropolitan area interconnection device 100 are connected to the transformer of the same metropolitan area, so that the multiple converter modules 110 in each flexible metropolitan area interconnection device 100 are powered by the transformer of the same metropolitan area; the DC sides of the multiple converter modules 110 in the first flexible metropolitan area interconnection device 100-1 among the multiple flexible metropolitan area interconnection devices 100 are respectively connected to the DC sides of the multiple converter modules 110 in the second flexible metropolitan area interconnection device 100-2, so as to form multiple groups of parallel power channels between the first flexible metropolitan area interconnection device 100-1 and the second flexible metropolitan area interconnection device 100-2, thereby forming a same-level parallel connection mode between the first flexible metropolitan area interconnection device 100-1 and the second flexible metropolitan area interconnection device 100-2; wherein, the multiple groups of parallel power channels between the first flexible metropolitan area interconnection device 100-1 and the second flexible metropolitan area interconnection device 100-2 are independent of each other and do not interfere with each other.

[0042] The present application provides a substation interconnection system, which is composed of multiple flexible substation interconnection devices, wherein each flexible substation interconnection device includes: multiple converter modules, the AC sides of the multiple converter modules in each flexible substation interconnection device are connected to the transformer of the same substation, so that the multiple converter modules in each flexible substation interconnection device are powered by the transformer of the same substation; the DC sides of the multiple converter modules in the first flexible substation interconnection device in the multiple flexible substation interconnection devices are respectively connected to the DC sides of the multiple converter modules in the second flexible substation interconnection device, so as to form multiple groups of parallel power channels between the first flexible substation interconnection device and the second flexible substation interconnection device, so that after a converter module in the multiple converter modules fails, the other converter modules in the multiple converter modules in the substation interconnection system that are not at fault can perform normal data exchange. Therefore, the substation interconnection system provided by the present application can, when any converter module fails, only issue a shutdown command to the failed converter module, without affecting the operation of other converter modules in the same substation. That is, the substation interconnection system can operate normally, thereby improving the reliability of the substation interconnection system.

[0043] Optionally, in one possible embodiment, continue to combine Figure 1 The DC sides of multiple converter modules in the first flexible metropolitan area interconnection device 100-1 are connected to the DC sides of multiple converter modules in the second flexible metropolitan area interconnection device 100-2 in a one-to-one correspondence. For example, the DC side of the converter module 110-1 in the first flexible metropolitan area interconnection device 100-1 is connected to the DC side of the converter module 110-1 in the second flexible metropolitan area interconnection device 100-2, and the DC side of the converter module 110-2 in the first flexible metropolitan area interconnection device 100-1 is connected to the DC side of the converter module 110-2 in the second flexible metropolitan area interconnection device 100-2, thereby forming multiple parallel power channels.

[0044] It should be noted that in the above embodiments, the substation interconnection system provided by the present application can meet the one-to-one correspondence between the DC side of multiple converter modules in the first flexible substation interconnection device 100-1 and the DC side of multiple converter modules in the second flexible substation interconnection device 100-2, that is, a converter module 110 of the first flexible substation interconnection device 100-1 can be connected to a converter module in the second flexible substation interconnection device 100-2 to form a one-to-one correspondence between the converter module of the first flexible substation interconnection device 100-1 and the converter module of the first flexible substation interconnection device 100-2, thereby establishing multiple groups of parallel power channels. Therefore, the substation interconnection system provided by the present application can only issue a shutdown command to the faulty converter module when a fault occurs in any converter module, without affecting the operation of other non-faulty converter modules in the same substation, that is, the substation interconnection system can work normally, thereby improving the reliability of the substation interconnection system.

[0045] exist Figure 1 On this basis, the substation interconnection system provided in the embodiment of the present application is described below with reference to the accompanying drawings. Figure 2 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 2 .like Figure 2 As shown, the DC side of one converter module 110 in the first flexible substation interconnection device 100-1 is connected to the DC side of some or all converter modules 110 in the second flexible substation interconnection device 100-2 to form multiple parallel power channels. In other words, the converter modules between multiple substations in the substation interconnection system provided by this application can also meet the situation of non-one-to-one correspondence, such as Figure 2 In the example, one converter module 110 of the first flexible substation interconnection device 100-1 can be connected to all converter modules of the second flexible substation interconnection device 100-2. Therefore, the substation interconnection system provided by this application can, upon receiving a fault in any converter module, only issue a shutdown command to the faulty converter module, without affecting the operation of other intact converter modules in the same substation. This means that the substation interconnection system can operate normally, thereby improving the reliability of the substation interconnection system.

[0046] Figure 3 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 3 .like Figure 3 As shown, one converter module 110 of the first flexible substation interconnection device 100-1 can be connected to the converter module 110-1 and the converter module 110-2 in the second flexible substation interconnection device 100-2, and then the remaining converter modules 110 in the second flexible substation interconnection device 100-2 are all idle and not connected. This forms two sets of parallel power channels. Therefore, the substation interconnection system provided by the present application can only issue a shutdown command to the faulty converter module when a fault occurs in any converter module, without affecting the operation of other non-faulty converter modules in the same substation, that is, the substation interconnection system can operate normally, thereby improving the reliability of the substation interconnection system.

[0047] exist Figure 1 On this basis, the substation interconnection system provided in the embodiment of the present application is described below with reference to the accompanying drawings. Figure 4 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 4 .like Figure 4 As shown, the substation interconnection system 200 may further include: a control device 210.

[0048] Each flexible platform interconnection device 100 may further include a control unit 120 .

[0049] The control unit 120 is connected to the multiple converter modules 110 in parallel, and the control unit 120 is connected to the control device 210. Optionally, the control unit 120 can be connected to the multiple converter modules 110 in parallel via a control area network (CAN) communication bus. Due to the anti-interference, serial communication, and priority characteristics of the control area network (CAN) communication bus, the control unit 120 can directly communicate with a master module (such as the converter module 110-1) among the multiple converter modules 110. The master module (such as the converter module 110-1) is configured to receive data from other converter modules among the multiple converter modules 110 except the master module (such as the converter module 110-1).

[0050] Optionally, in one possible embodiment, continue to combine Figure 4 The control unit 120 is connected to the control device 210 via a wired Ethernet communication line, or the control unit 120 is connected to the control device 210 via a wireless Ethernet communication line to establish a limited or wireless communication connection between the control unit 120 and the control device 210, thereby improving the versatility of the substation interconnection system.

[0051] The control device 210 is the master controller of the substation interconnection system 200 and can be selected based on actual conditions. For example, the control device 210 can be an EMS (Energy Management System). The converter module 110 is used for AC / DC conversion and can be selected based on actual conditions. For example, the converter module 110 can be an ACDC module. The control unit 120 is the controller within each flexible substation interconnection device 100 and can be selected based on actual conditions. For example, the control unit 120 can be a CSCU (Central Switch and Control Unit).

[0052] It should be noted that if Figure 4 As shown, in the substation interconnection system, the converter module 110-1 in the same flexible substation interconnection device 100 is the master module, and the remaining converter modules 110 are slave modules. When multiple converter modules 110 are communicatively connected to the control device 210 in parallel, the master module (converter module 110-1) is generally directly communicatively connected to the control device 210 to transmit data from each slave module collected by the master module (converter module 110-1) to the control device 210. However, it is also possible to communicatively connect multiple converter modules in the same flexible substation interconnection device 100 to the control device 210 to transmit data from multiple converter modules 110 to the control device 210.

[0053] For example, in the actual application of the dual-area interconnection scenario, there are two AC distribution areas, two flexible area interconnection devices 100, and other loads in the two areas. Each area is provided with a flexible area interconnection device 100, and each flexible area interconnection device 100 has at least two converter modules 110. The AC sides of the at least two converter modules 110 are connected in parallel and connected to the low-voltage side of the transformer in the area where they are located; the DC sides of the converter modules 110 in the two flexible area interconnection devices 100 are grouped in pairs, one-to-one, and connected in groups. There are a total of two groups of DC side groups of converter modules 110 to form two groups of converter channels. Each group of converter channels is independently connected and does not interfere with each other. When a slave module fails, the power that the area interconnection system 200 re-sends to other converter modules will increase, and the area interconnection system 200 will limit the final power sent to avoid exceeding the power upper limit (for example, 65KW) output by the converter module 110.

[0054] In an optional embodiment, when the master module (converter module 110-1) fails, the control device 210 in the substation interconnection system 200 reselects the converter module with the smallest address from all healthy converter modules after 3 seconds and sets it as the master module. The master module then redistributes power, and all slave modules upload their device status to the master module. The master module then excludes the faulty converter module when performing power distribution. It should be noted that setting the waiting time of the control device 210 to 3 seconds is merely an example and can be adjusted according to actual application. No limitation is imposed here.

[0055] The substation interconnection system provided by this application is further composed of a control device and multiple flexible substation interconnection devices. The control unit in each flexible substation interconnection device is connected in parallel to multiple converter modules, and the control unit is connected to the control device. Thus, this application can achieve data exchange between the control unit in the flexible substation interconnection device and the control device in the substation interconnection system.

[0056] exist Figure 4 On this basis, the substation interconnection system provided in the embodiment of the present application is described below with reference to the accompanying drawings. Figure 5 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 5 .like Figure 5 As shown, the substation interconnection system 100 may further include: a plurality of energy storage modules 130 .

[0057] Among them, the DC sides of multiple converter modules 110 in the first flexible metropolitan area interconnection device 100-1 are respectively connected to the DC sides of multiple converter modules 110 in the second flexible metropolitan area interconnection device 100-2 through multiple energy storage modules 130 to form multiple groups of independent energy storage and conversion channels between the first flexible metropolitan area interconnection device 100-1 and the second flexible metropolitan area interconnection device 100-2.

[0058] In the substation interconnection system provided by the present application, the DC sides of multiple converter modules in the first flexible substation interconnection device are connected to the DC sides of multiple converter modules in the second flexible substation interconnection device through multiple energy storage modules, so as to form multiple groups of independent energy storage conversion channels between two adjacent substations, so that when a converter module among the multiple converter modules fails, the operation of other non-faulty converter modules in the same substation will not be affected.

[0059] In order to clearly illustrate the substation interconnection system provided by the present application, the present application also provides another substation interconnection system. The following continues to illustrate the substation interconnection system provided in the embodiment of the present application with reference to the accompanying drawings. Figure 6 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 6 .like Figure 6 As shown, the platform interconnection system 200 may include: multiple groups of flexible platform interconnection devices 100.

[0060] Each group of flexible platform interconnection devices 100 may include: a plurality of flexible interconnection devices 140 , and each flexible interconnection device 140 may include: a converter module 110 .

[0061] The AC sides of the converter modules 110 of the multiple flexible interconnection devices 140 in each group are respectively connected to the transformers of the corresponding substations, and the DC sides of the converter modules 110 of the multiple flexible interconnection devices 140 in each group are connected in parallel.

[0062] For example, when a flexible interconnection device is used between multiple stations, the DC side of the flexible interconnection device is connected in groups, such as Figure 4 As shown, the six substations are divided into two groups, each with three substations. When a flexible interconnection device fails, the flexible interconnection devices in other groups are not affected, thereby preventing the failure of a single flexible interconnection device from causing all converter modules 110 on the DC bus to fail to work normally.

[0063] The present application provides a substation interconnection system, which is composed of multiple groups of flexible substation interconnection devices, wherein each group of flexible substation interconnection devices includes: multiple flexible interconnection devices, each flexible substation interconnection device includes a converter module; the AC sides of the converter modules of the multiple flexible interconnection devices in each group are respectively connected to the transformers of multiple substations, and the DC sides of the converter modules of the multiple flexible interconnection devices in each group are connected in parallel to avoid the failure of any flexible substation interconnection device to cause the converter module on the DC bus to fail to operate normally.

[0064] Optionally, in one possible embodiment, continue to combine Figure 6 , the number of the converter module 110 in each flexible interconnection device 100 is one; Figure 7A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 7 .like Figure 7 As shown, each flexible interconnection device 100 includes a plurality of converter modules 110 .

[0065] exist Figure 6 On this basis, the substation interconnection system provided in the embodiment of the present application is described below with reference to the accompanying drawings. Figure 8 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 8 .like Figure 8 As shown, each group may further include: an energy storage module 130 .

[0066] The DC ends of the converter modules 110 of the multiple flexible interconnection devices 100 in each group are electrically connected in parallel to the energy storage module 130 to solve the over-distribution problem in the substation interconnection system, thereby avoiding the problem of unstable power transfer between multiple substations.

[0067] In the substation interconnection system provided by the present application, the energy storage module in each group of flexible substation interconnection devices is electrically connected in parallel with the DC end of the converter modules of multiple flexible substation interconnection devices in each group to solve the over-capacity problem in the substation interconnection system and thereby avoid the problem of instability during power transfer between multiple substations.

[0068] exist Figure 8 On this basis, the substation interconnection system provided in the embodiment of the present application is described below with reference to the accompanying drawings. Figure 9 A schematic diagram of the structure of a substation interconnection system provided in an embodiment of the present application Figure 9 .like Figure 9 As shown, the substation interconnection system 200 may further include a control device 210 . Each flexible interconnection device may further include a control unit 120 .

[0069] Among them, the control unit 120 is connected to the converter module 110; each control unit 120 in multiple flexible interconnection devices in each group is connected in parallel to the control device 210 to achieve unified management and control of the control device 210, so as to avoid the failure of any flexible area interconnection device causing all converter modules on the DC bus to fail to operate normally.

[0070] The substation interconnection system provided in the present application can be composed of a control device and multiple groups of flexible substation interconnection devices. The control unit in each flexible substation interconnection device is communicated and connected to the converter module; the control units in the multiple flexible substation interconnection devices in each group are communicated and connected to the control device in parallel to achieve unified management and control of the control device, so as to avoid the failure of any flexible substation interconnection device causing all converter modules on the DC bus to fail to operate normally.

[0071] Optionally, in one possible embodiment, continue to combine Figure 9 The control unit 120 is connected to the converter module 110 via the control area network CAN communication bus. Due to the anti-interference, serial communication and priority characteristics of the control area network CAN communication bus, the control unit 120 can communicate directly with the converter module 110.

[0072] Optionally, in one possible embodiment, continue to combine Figure 9 Each control unit is connected to the control device via a wired Ethernet communication line, or each control unit is connected to the control device via a wireless Ethernet communication line to establish a limited or wireless communication connection between the control unit 120 and the control device 210, thereby improving the versatility of the substation interconnection system.

[0073] In order to facilitate the understanding of the above-mentioned area interconnection system, Figure 1 For example, the embodiment of the present application also provides an example of a process of a method for redistributing power after a converter module fails, which is described below in conjunction with the accompanying drawings. Figure 10 This is a flow chart of a power redistribution method provided in an embodiment of the present application. Figure 10 As shown, the power redistribution method provided in the embodiment of the present application may include:

[0074] S301. Obtain the required setting power of each flexible area interconnection device.

[0075] Specifically, Figure 1 For example, at the first moment t1, when each flexible metropolitan area interconnection device 100 in the metropolitan area interconnection system 200 is performing power transfer, the required setting power Pset_FIDx of each flexible metropolitan area interconnection device 100 corresponding to the metropolitan area interconnection system 200 is obtained.

[0076] S302: After a first converter module among the multiple converter modules fails, obtain a required power of a single available converter module among the multiple converter modules.

[0077] Specifically, if the first converter module fails at the first moment t2, the power requirement Pset_FIDx of each flexible substation interconnection device 100 corresponding to the substation interconnection system 200 is set, and the number N of converter modules that can operate normally is used to calculate the required power Pset_pcs of a single converter module at this time using the following formula (1).

[0078] Pset_pcs=Pset_FIDx / N Formula (1)

[0079] S303: Determine whether the required power of a single converter module exceeds the upper limit of the output power of the single converter module.

[0080] S304: If yes, reset the required power of the single converter module.

[0081] Specifically, the required power Pset_pcs of a single converter module is compared with the output power upper limit Pmax_pcs of the required power of a single converter module. If │(Pmax_pcs) / (Pset_pcs)│>1, it means that the current required power Pset_pcs of the single converter module exceeds the output power upper limit Pmax_pcs of the single converter module. Then the final required power Pset_pcs of the single converter module can be set to Pset_pcs=(Pset_pcs)*│(Pmax_pcs) / (Pset_pcs)│; otherwise, the current required power Pset_pcs of the single converter module does not reach the upper limit and meets the demand, then the final required power Pset_pcs of the single converter module is itself.

[0082] It should be noted that when a group of converter modules in the substation interconnection system 200 fails, the control device 210 in the substation interconnection system 200 will re-distribute power to other converter modules. At this time, the demand setting power Pset_FIDx received by each converter module will increase. The substation interconnection system 200 will limit the demand power Pset_pcs of a single converter module that is finally distributed to avoid exceeding the output power upper limit Pmax_pcs of a single converter module, thereby improving the stability and reliability of the substation interconnection system 200.

[0083] The present application provides a power redistribution method, which first obtains the required power setting of each flexible substation interconnection device, and then determines that the first converter module among multiple converter modules fails, obtains the required power of a single available converter module among multiple converter modules, and then determines whether the required power of a single converter module exceeds the upper limit of the output power of a single converter module. For a single converter module whose required power exceeds the upper limit of the output power of a single converter module, the required power of the single converter module is reset. Therefore, in the substation flexible station application scenario, the present application can connect the DC side of the flexible substation interconnection device according to the converter module grouping, one to one correspondence, and change the converter module from a one-master and multiple-slave mode to a same-level parallel mode. Multiple converter modes independently interact with the substation interconnection system for data streams, so that when a converter module fails, it will not affect the normal operation of other converter modules, effectively improving the reliability of the substation interconnection system.

[0084] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A substation interconnection system, characterized in that: include: Multiple flexible area interconnection devices, wherein each flexible area interconnection device comprises: multiple converter modules, wherein the AC sides of the multiple converter modules in each flexible area interconnection device are connected to the transformer of the same area; The DC sides of the multiple converter modules in the first flexible metro area interconnection device among the multiple flexible metro area interconnection devices are respectively connected to the DC sides of the multiple converter modules in the second flexible metro area interconnection device to form multiple groups of parallel power channels between the first flexible metro area interconnection device and the second flexible metro area interconnection device.

2. The substation interconnection system according to claim 1, characterized in that: The DC sides of the multiple converter modules in the first flexible metropolitan area interconnection device are connected to the DC sides of the multiple converter modules in the second flexible metropolitan area interconnection device in a one-to-one correspondence to form the multiple groups of parallel power channels.

3. The substation interconnection system according to claim 1, characterized in that: The DC side of a converter module in the first flexible metropolitan area interconnection device is connected to the DC sides of some or all converter modules in the second flexible metropolitan area interconnection device to form the multiple groups of parallel power channels.

4. The substation interconnection system according to claim 1, characterized in that: The substation interconnection system further includes: a control device; each flexible substation interconnection device further includes: a control unit, the control unit is connected to the multiple converter modules in parallel, and the control unit is connected to the control device.

5. The substation interconnection system according to claim 1, characterized in that: The substation interconnection system also includes: multiple energy storage modules, and the DC sides of the multiple conversion modules in the first flexible substation interconnection device are respectively connected to the DC sides of the multiple conversion modules in the second flexible substation interconnection device through the multiple energy storage modules to form multiple groups of energy storage and conversion channels between the first flexible substation interconnection device and the second flexible substation interconnection device.

6. A substation interconnection system, characterized in that: include: Multiple groups of flexible area interconnection devices, wherein each group of flexible area interconnection devices includes: multiple flexible interconnection devices, each flexible interconnection device includes: a converter module; The AC sides of the converter modules of the multiple flexible interconnection devices in each group are respectively connected to the transformers of the corresponding substations, and the DC sides of the converter modules of the multiple flexible interconnection devices in each group are connected in parallel.

7. The substation interconnection system according to claim 6, characterized in that: The number of the converter modules in each flexible interconnection device is one or more.

8. The substation interconnection system according to claim 6, characterized in that: Each group further includes: an energy storage module, and the DC ends of the converter modules of the multiple flexible interconnection devices in each group are electrically connected to the energy storage module in parallel.

9. The substation interconnection system according to claim 6, characterized in that: The substation interconnection system further includes: a control device; each flexible interconnection device further includes: a control unit, the control unit being connected to the conversion module; Each control unit in the plurality of flexible interconnection devices in each group is connected in parallel to the control device.

10. The substation interconnection system according to claim 9, characterized in that: Each control unit is connected to the control device via a wired Ethernet communication line, or each control unit is connected to the control device via wireless Ethernet communication.

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