Reverse power flow processing method and cut-through power supply traction power transformation system

Abstract

The invention provides a reverse power flow processing method and a cut-through power supply traction power transformation system, and is applied to the cut-through power supply traction power transformation system, and the method comprises the steps: determining the operation condition of the cut-through power supply traction power transformation system according to the current information of one or more traction substations in a plurality of traction substations; determining an adjustment strategy corresponding to the operation condition, and obtaining adjustment parameters required by the adjustment strategy; and according to the adjustment strategy, controlling corresponding equipment in one or more traction substations in the plurality of traction substations to work according to the adjustment parameters. In the working process of the through power supply traction power transformation system, the operation condition of the traction substation is determined according to the current information of the traction substation, and the corresponding adjustment parameters are determined according to the operation condition of the traction substation, so that the corresponding equipment is controlled to work according to the adjustment parameters; the ride-through power generated by the traction substation can be reduced, and the system stability is improved.

Description

Technical Field

[0001] The present application relates to the field of power supply and distribution, and in particular, to a reverse power flow processing method and a through-power supply traction substation system. Background Art

[0002] The through power supply of electrified railways (for example, bilateral power supply) has the advantages of high power supply reliability, good grid voltage level, large power supply capacity, and small power loss. However, under normal circumstances, the traction substations on both sides form a parallel structure with the power grid. When the traction substation is unloaded, power and current flow through the traction substation. The corresponding power is called ride-through power. When the traction substation is in a regenerative condition, regenerative power may also be generated. These reverse currents such as ride-through power and regenerative power will affect the power distribution and power dispatching of the power system, and also cause metering problems in the traction power supply system, resulting in economic losses for traction users.

[0003] At present, the common way to deal with reverse power flow is to set up a corresponding power flow control unit to regulate the reverse power flow so that the reverse power flow returned from the traction substation can be transferred to the distribution system and / or energy storage equipment for utilization.

[0004] However, when there are many reverse flows, it is difficult for the distribution system and / or energy storage equipment to completely transfer and utilize these reverse flows, and the remaining reverse flows may still have an impact on the power system and affect the system stability. Summary of the invention

[0005] In view of this, the purpose of the embodiments of the present application is to provide a reverse power flow processing method and a through-power supply traction substation system, which can reduce the through power generated by the traction substation and improve the system stability performance.

[0006] In the first aspect, an embodiment of the present application provides a reverse power flow processing method, which is applied to a through-power supply traction substation system; wherein the through-power supply traction substation system includes multiple traction substations, and two adjacent traction substations are connected by a switch; the method includes: determining the operating condition of the through-power supply traction substation system according to the current information of one or more traction substations among the multiple traction substations; determining an adjustment strategy corresponding to the operating condition, and obtaining adjustment parameters required for the adjustment strategy; according to the adjustment strategy, controlling the corresponding equipment in one or more traction substations among the multiple traction substations to operate according to the adjustment parameters.

[0007] In the above implementation process, during the operation of the through-power supply traction substation system, the operating condition of the traction substation is first determined based on the current information of the traction substation, and the corresponding adjustment parameters are determined based on the operating condition of the traction substation to control the corresponding equipment to work according to the adjustment parameters. By adjusting the parameters of the corresponding equipment, the through-power supply generated by the traction substation can be reduced and the system stability can be improved. In addition, by determining the corresponding adjustment strategy according to the different operating conditions of the traction substation, the through-power supply traction substation system can be reused in multiple scenarios to improve the utilization rate of the through-power supply traction substation system.

[0008] In one embodiment, the through-power supply traction substation system also includes: a first single-phase converter and a transformer; a primary side of the transformer is respectively connected in series between the traction busbar of each traction substation and the traction transformer feeder line, and each secondary side of the transformer is respectively connected to a first port of the first single-phase converter, and the second port of each first single-phase converter is respectively connected to a low-voltage side distribution system; the operating conditions include: no-load conditions, and the adjustment parameters include first adjustment parameters; determining the adjustment strategy corresponding to the operating conditions and obtaining the adjustment parameters required for the adjustment strategy include: obtaining the return to one or more traction substations among the multiple traction substations ride through power; determining whether the ride through power exceeds the ride through power limit; in the case that the ride through power exceeds the ride through power limit, determining a first adjustment parameter of the first single-phase converter connected to the traction substation whose ride through power exceeds the ride through power limit; according to the adjustment strategy, controlling corresponding equipment in one or more traction substations among the multiple traction substations to operate according to the adjustment parameter, including: controlling the first single-phase converter connected to the traction substation whose ride through power exceeds the ride through power limit to operate according to the first adjustment parameter; wherein the first adjustment parameter is configured to reduce the ride through power of one or more traction substations among the multiple traction substations.

[0009] In the above implementation process, when the traction substation is in a no-load condition and the through-power traction substation in the through-power traction substation system generates through-power, by determining the first adjustment parameter of the first single-phase converter and controlling the operation of the first single-phase converter based on the first adjustment parameter, the voltage amplitude and phase size of the traction bus output connected to it can be adjusted by the first single-phase converter, thereby reducing the difference between the voltage amplitude and phase size of the traction bus output of the traction substation, so as to reduce the size of the through-power, reduce the configuration of the through-power utilization device capacity, and reduce the system cost. In addition, it can also effectively solve the through-power problem of the bilateral power supply system, reduce the through-power sent back to the power system, and improve the power supply stability of the power system.

[0010] In one embodiment, when the ride-through power exceeds the ride-through power limit, determining the first adjustment parameter of the first single-phase converter connected to the traction substation whose ride-through power exceeds the ride-through power limit includes: when the ride-through power exceeds the ride-through power limit, determining the traction substation in the through-power traction substation system that needs to perform parameter adjustment according to a priority rule; and calculating the first adjustment parameter of the first single-phase converter connected to the traction substation that needs to perform parameter adjustment according to a set rule.

[0011] In one embodiment, determining the traction substations in the through-power supply traction substation system that need to be adjusted in parameters according to the priority rule includes: when there are multiple traction substations in the through-power supply traction substation system whose first voltage difference between the bus voltage and the set voltage is within the first preset difference range, determining that other traction substations in the through-power supply traction substation system except for the multiple traction substations whose first voltage difference is within the first preset difference range are traction substations that need to be adjusted in parameters; calculating the first adjustment parameter of the first single-phase converter connected to the traction substation that needs to be adjusted in parameters according to the set rule includes: determining the first adjustment parameter of the first single-phase converter connected to each traction substation that needs to be adjusted in parameters according to the bus voltage of the traction substation that needs to be adjusted in parameters and the set voltage; wherein the first adjustment parameter is configured to reduce the difference between the bus voltage of the traction substation that needs to be adjusted in parameters and the set voltage.

[0012] In one embodiment, determining the traction substations in the through-power supply traction substation system that need parameter adjustment according to the priority rule includes: if the bus voltages of multiple traction substations whose voltage differences are within the preset difference range are not within the preset voltage range, determining that all traction substations in the through-power supply traction substation system are traction substations that need parameter adjustment; calculating the first adjustment parameter of the first single-phase converter connected to the traction substation that needs parameter adjustment according to the set rules includes: determining the first adjustment parameter of the first single-phase converter connected to each traction substation that needs parameter adjustment based on the bus voltage of the traction substation that needs parameter adjustment and the average value of the bus voltage; wherein the first adjustment parameter is configured to reduce the difference between the bus voltage of the traction substation and the average value of the bus voltage.

[0013] In one embodiment, the determining of the traction substations in the through-power supply traction substation system that need parameter adjustment according to the priority rule includes: when the voltage difference of the bus voltages of multiple traction substations in the through-power supply traction substation system is not within the preset difference range, calculating the average bus voltage of multiple traction substations whose bus voltages are within the preset voltage range; determining that the traction substation whose bus voltage is different from the bus voltage average value is the traction substation that needs parameter adjustment; calculating the first adjustment parameter of the first single-phase converter connected to the traction substation that needs parameter adjustment according to the set rule includes: determining the first adjustment parameter of the first single-phase converter connected to each traction substation that needs parameter adjustment according to the bus voltage of the traction substation that needs parameter adjustment and the bus voltage average value; wherein the first adjustment parameter is configured to reduce the difference between the bus voltage of the traction substation and the bus voltage average value.

[0014] In the above implementation process, by setting priority rules to determine the traction substations that need parameter adjustment, as few traction substations as possible can be determined for parameter adjustment according to demand, thereby reducing the number of traction substations that need parameter adjustment and improving adjustment efficiency.

[0015] In one embodiment, the through-feed traction substation system further includes: a second single-phase converter and a three-phase converter; the traction busbar of each traction substation is respectively connected to a first port of the second single-phase converter, the second port of each second single-phase converter is respectively connected to a first port of the three-phase converter, and the second port of each three-phase converter is respectively connected to a low-voltage side distribution system; after the first single-phase converter connected to the traction substation whose ride-through power exceeds the ride-through power limit is controlled to operate according to the first adjustment parameter, the method further includes: when one or more traction substations among the multiple traction substations still have residual ride-through power: controlling the second single-phase converter to be in a rectification state, and controlling the three-phase converter to be in an inversion state; transmitting the residual ride-through power after rectification by the second single-phase converter and inversion by the three-phase converter to the low-voltage side distribution system; wherein the residual ride-through power after rectification by the second single-phase converter and inversion by the three-phase converter is configured for use by the low-voltage side distribution system.

[0016] In the above implementation process, after adjustment by the first single-phase converter, if there is still residual ride-through power in the traction substation, the residual ride-through power can be rectified and inverted and then transmitted to the low-voltage side distribution system by controlling the corresponding working states of the second single-phase converter and the three-phase converter, so that the residual ride-through power can be used by the electrical equipment in the low-voltage side distribution system, thereby improving the utilization rate of the ride-through power. In addition, by using the residual ride-through power through the low-voltage side distribution system, the residual ride-through power in the system can be reduced, thereby reducing the ride-through power returned to the three-phase system, reducing the impact of the ride-through power on the traction transformer feeder line, and improving the power supply stability and safety of the traction transformer feeder line.

[0017] In one embodiment, the through-power supply traction substation system further includes: a second single-phase converter and a three-phase converter; the traction bus of each traction substation is respectively connected to a first port of the second single-phase converter, the second port of each second single-phase converter is respectively connected to a first port of the three-phase converter, and the second port of each three-phase converter is respectively connected to a low-voltage side distribution system; the operating conditions include: regeneration conditions; determining the adjustment strategy corresponding to the operating conditions and obtaining the adjustment parameters required for the adjustment strategy include: obtaining the regeneration power of one or more traction substations among the multiple traction substations; when the regeneration power is less than or equal to the power of the three-phase converter: controlling the second single-phase converter to be in a rectification state, and controlling the three-phase converter to be in an inversion state; transmitting the regeneration power rectified by the second single-phase converter and inverted by the three-phase converter to the low-voltage side distribution system; wherein the regeneration power rectified by the second single-phase converter and inverted by the three-phase converter is configured for use by the low-voltage side distribution system.

[0018] In the above implementation process, by controlling the corresponding working states of the second single-phase converter and the three-phase converter, the regenerative power is rectified and inverted and then transmitted to the low-voltage side distribution system, so that the electrical equipment in the low-voltage side distribution system can use the regenerative power, thereby improving the utilization rate of the regenerative power. In addition, by using the regenerative power through the low-voltage side distribution system, the regenerative power in the system can be reduced, thereby reducing the regenerative power returned to the three-phase system, reducing the impact of the regenerative power on the traction transformer feeder line, and improving the power supply stability and safety of the traction transformer feeder line.

[0019] In one embodiment, the through-power supply traction substation system also includes: an energy storage device; the energy storage device is connected to the second port of the second single-phase converter; the method also includes: when the regenerative power is greater than or equal to the power of the three-phase converter: controlling the second single-phase converter to be in a rectification state, and controlling the three-phase converter to be in an inversion state; transmitting the regenerative power rectified by the second single-phase converter and inverted by the three-phase converter to the low-voltage side power distribution system; wherein the regenerative power transmitted to the low-voltage side power distribution system is equal to the power of the three-phase converter; controlling the energy storage device to store the remaining regenerative power.

[0020] In the above implementation process, when the regenerative power is greater than or equal to the power of the three-phase converter, the remaining regenerative power used by the low-voltage side distribution system can be sent to the energy storage device to charge the energy storage device, and the remaining regenerative power is further consumed by the energy storage device to further reduce the regenerative power returned to the three-phase system, reduce the impact of the regenerative power on the traction transformer feeder line, and improve the power supply stability and safety of the traction transformer feeder line.

[0021] In one embodiment, the through-power supply traction substation system further includes: an energy storage device and a second single-phase converter; the traction bus in each traction substation is respectively connected to a first port of the second single-phase converter, and the second port of each second single-phase converter is respectively connected to one of the energy storage devices; the operating conditions include: traction conditions; determining the adjustment strategy corresponding to the operating conditions and obtaining the adjustment parameters required for the adjustment strategy include: when the traction power is less than the power of the energy storage device, controlling the energy storage device to discharge according to the traction power, and controlling the second single-phase converter to be in an inverter state; when the traction power is greater than or equal to the power of the energy storage device, controlling the energy storage device to discharge according to the power of the energy storage device, and controlling the second single-phase converter to be in an inverter state; wherein the power after inversion by the second single-phase converter is configured to be used by traction equipment in one or more traction substations among the multiple traction substations.

[0022] In the above implementation process, the power supplied to the traction substation is determined based on the relationship between the traction power and the power of the energy storage device. That is, within the allowable range of the power of the energy storage device and the power of the traction substation, the traction substation is supplied with power at a relatively small power supply, so that as much electric energy stored in the energy storage device as possible can be transmitted to the traction substation under the premise of ensuring line safety, thereby reducing the electric energy that the three-phase system needs to provide to the traction substation and reducing electricity costs.

[0023] In one embodiment, the through-power supply traction substation system also includes: a second single-phase inverter; the traction bus of each traction substation is respectively connected to a first port of the second single-phase inverter; the operating conditions include: inter-zone operation, and the inter-zone operation is to shut down one or more traction substations in the through-power supply traction substation system; determining the adjustment strategy corresponding to the operating condition and obtaining the adjustment parameters required for the adjustment strategy include: controlling the second single-phase inverter to generate a reactive current whose phase exceeds the voltage phase of the traction substation connected thereto by 90°; wherein the reactive current is configured to support the voltage in one or more traction substations among the multiple traction substations.

[0024] In the above implementation process, under the inter-regional operation condition, reactive power is generated by the second single-phase converter, which can reduce the power supply difference between traction substations in different areas and improve the power supply stability of the traction substations.

[0025] In one embodiment, the through-power supply traction substation system further includes: a second single-phase converter and a three-phase converter; the traction bus of each traction substation is respectively connected to the first port of the second single-phase converter, the second port of each second single-phase converter is respectively connected to the first port of the three-phase converter, and the second port of each three-phase converter is respectively connected to a low-voltage side distribution system; the operating conditions include: exiting operation, and the exiting operation means that some traction substations in the through-power supply traction substation system exit operation; determining the adjustment strategy corresponding to the operating condition and obtaining the adjustment parameters required for the adjustment strategy include: controlling the three-phase converter to be in a rectifying state; controlling the second single-phase converter to be in an inverting state; wherein the electric energy in the low-voltage side distribution system after rectification by the three-phase converter and inversion by the second single-phase converter is configured as an emergency power supply for use by traction equipment of one or more traction substations in the traction substations that have exited operation.

[0026] In the above implementation process, when the traction substation is in an out-of-operation condition, the electric energy in the low-voltage side distribution system is rectified and inverted through a three-phase converter and a second single-phase converter and then transmitted to the traction equipment in the traction substation for use by the traction equipment. This can provide emergency rescue when an emergency occurs in the traction substation, and ensure the safety and stability of the operation of the traction equipment in the traction substation.

[0027] In one embodiment, the through-power supply traction substation system further includes: a transformer and a first single-phase converter; a primary side of the transformer is connected in series between the traction bus of each traction substation and the traction transformer feeder line, and a first port of the first single-phase converter is connected to the secondary side of each transformer; before determining the operating condition of the through-power supply traction substation system according to the current information of one or more traction substations among the multiple traction substations, the method further includes: calculating the average bus voltage of two adjacent traction substations; calculating the working voltage of the corresponding first single-phase converter according to the average bus voltage and the bus voltage of each traction substation; controlling each first single-phase converter to operate according to the corresponding working voltage; wherein the difference between the superimposed voltage after the working voltage of the first single-phase converter and the bus voltage of the corresponding traction substation is superimposed and the average bus voltage is within a preset range; when it is determined that the difference between the superimposed voltage of the two adjacent traction substations and the average bus voltage is within the preset range, controlling the switch to close.

[0028] In the above implementation process, before closing the switch, it is first calculated whether the traction substation meets the closing conditions. When it is determined that the traction substation meets the closing conditions, the switch is closed to form bilateral power supply, which can improve the stability of the traction substation.

[0029] In the second aspect, an embodiment of the present application also provides a through-power supply traction substation system, including: the through-power supply traction substation system is used to execute the method described in any one of claims 1 to 9 above, and the system includes: multiple traction substations, multiple transformers, multiple first single-phase converters, multiple second single-phase converters and multiple three-phase converters; adjacent traction substations are connected by switches; a primary side of the transformer is respectively connected in series between the traction busbar of each traction substation and the traction transformer feeder line, and the secondary side of each transformer is respectively connected to the first port of the first single-phase converter; the second port of each first single-phase converter is respectively connected to the first port of the three-phase converter; the traction busbar of each traction substation is respectively connected to the first port of the second single-phase converter, and the second port of each second single-phase converter is respectively connected to the first port of the three-phase converter; the second port of each three-phase converter is respectively connected to a low-voltage side distribution system.

[0030] In the above implementation process, by setting the traction busbar to be connected with the transformer and the first single-phase converter, when the cross-over power is formed between two adjacent traction substations, the voltage of the traction substation connected thereto can be adjusted by the first single-phase converter, thereby reducing the voltage difference between the two adjacent traction substations, thereby reducing the generation of cross-over power, thereby reducing the configuration of the cross-over power utilization device capacity and reducing the system cost. At the same time, the cross-over power problem of the bilateral power supply system can be effectively solved to a certain extent, avoiding the reverse power transmission to the power system. In addition, by setting the second single-phase converter and the three-phase converter, the second single-phase converter and the three-phase converter can transmit the cross-over power that still exists after adjustment to the low-voltage side distribution system through rectification, inversion and other actions, for use by the low-voltage side distribution system, thereby improving the utilization rate of the cross-over power and reducing the power supply of the power supply system.

[0031] In one embodiment, it also includes: a plurality of two-branch switches; each of the two-branch switches includes a first branch contact and a second branch contact; the first terminal of each of the first branch contacts is connected to a traction bus of the traction substation, and the second terminal is connected to the traction transformer feeder line; the first terminal of each of the second branch contacts is connected to the traction transformer feeder line and a second terminal of the first branch contact, and the second terminal is connected to a terminal of the primary side of the transformer; the other terminal of the primary side of each of the transformers is connected to a first terminal of the first branch contact and a traction bus of the traction substation; wherein the first branch contact and the second branch contact operate in a complementary conduction mode.

[0032] In the above implementation process, by setting up two branch switches, and the first branch contact and the second branch contact of each two-branch switch working in the complementary conduction mode, the transformer can be controlled to bypass and exit the through-power supply system under non-no-load conditions, thereby avoiding the power of the traction transformer feeder line from flowing into the transformer and the first single-phase converter, thereby reducing the capacity requirements of the transformer and the first single-phase converter.

[0033] In one embodiment, it also includes: multiple energy storage devices; the energy storage devices are connected to the second port of the first single-phase inverter device and the second port of the second single-phase inverter device; wherein the energy storage devices are configured to store the residual power of one or more traction substations among multiple traction substations; the residual power includes one or more of residual ride-through power and residual regenerative power; the energy storage devices are also configured to supply power to the corresponding traction substation through the second single-phase inverter device.

[0034] In the above implementation process, by setting up an energy storage device, when the low-voltage side power distribution system cannot fully utilize the reverse power flow, the remaining power can be stored through the energy storage device, thereby reducing the reverse power flow in the system and reducing the negative impact of the reverse power flow on the power grid through the traction transformer feeder line. In addition, the power stored in the storage device can also be used to supply power to the traction substation, reducing the power supply of the traction transformer feeder line to the traction substation and reducing the power supply cost.

[0035] In a third aspect, an embodiment of the present application further provides an electronic device, comprising: a processor and a memory, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the machine-readable instructions are executed by the processor to perform the steps of the method in the above-mentioned first aspect, or any possible implementation of the first aspect.

[0036] In a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the flow control method in the above-mentioned first aspect, or any possible implementation of the first aspect are executed.

[0037] In order to make the above-mentioned objects, features and advantages of the present application more obvious and understandable, embodiments are given below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] 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.

[0039] Figure 1 A schematic diagram of the overall structure of the through-power supply traction substation system provided in the embodiment of the present application;

[0040] Figure 2 A schematic diagram of the connection of each traction substation in the through-feed traction substation system provided in an embodiment of the present application;

[0041] Figure 3 A schematic diagram of the connection of each traction substation including two branch switches in the through-power supply traction substation system provided in an embodiment of the present application;

[0042] Figure 4 A block diagram of an electronic device provided in an embodiment of the present application;

[0043] Figure 5A flowchart of a reverse power flow processing method provided in an embodiment of the present application;

[0044] Figure 6 A schematic diagram of the functional modules of the power utilization device provided in an embodiment of the present application.

[0045] Description of the drawings: 100 - traction substation, 110 - traction bus, 200 - transformer, 300 - first single-phase converter, 400 - second single-phase converter, 500 - multiple three-phase converters, 600 - energy storage device, 700 - two-branch switch, 710 - first branch contact, 720 - second branch contact, 20 - low-voltage side distribution system, 30 - traction transformer feeder line, 40 - switch. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present application will be described below in conjunction with the accompanying drawings in the embodiments of the present application.

[0047] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0048] Normally, when the traction substation is unloaded, there is a through power flow in the traction substation. The through power may be fed back to the traction transformer feeder line, affecting the stability of the traction transformer feeder line. In addition, the regenerative power in the traction substation may also be fed back to the traction transformer feeder line, affecting the stability of the traction transformer feeder line. For these reverse currents, the commonly used method is to set up a power utilization device to timely utilize the reverse current in the traction substation through the power utilization device.

[0049] However, the inventor of the present application has found through long-term research that, although the method of using the reverse current by setting up a power utilization device can reduce the reverse current to a certain extent, when a large amount of reverse current is generated, the power utilization device cannot fully utilize or transfer the reverse current, and the remaining reverse current may still be sent back to the three-phase system. If the capacity of the power utilization device is increased so that the power utilization device can transfer or utilize more reverse current, although the reverse current can be reduced or even eliminated, the large-capacity power utilization device greatly increases the cost of the system.

[0050] In view of this, the present application proposes a reverse power flow processing method. During the operation of the through-power supply traction substation system, the operating condition of the traction substation is first determined according to the current information of the traction substation, and the corresponding adjustment parameters are determined according to the operating condition of the traction substation to control the corresponding equipment to work according to the adjustment parameters. By adjusting the parameters of the corresponding equipment, the through-power supply generated by the traction substation can be reduced and the system stability can be improved. In addition, by determining the corresponding adjustment strategy according to the different operating conditions of the traction substation, the through-power supply traction substation system can be reused in multiple scenarios to improve the utilization rate of the through-power supply traction substation system.

[0051] To facilitate understanding of this embodiment, a through-power supply traction substation system that executes a reverse power flow processing method disclosed in an embodiment of the present application is first introduced in detail.

[0052] like Figure 1 , Figure 2 , which is a schematic diagram of the structure of a through-power supply traction substation system provided in an embodiment of the present application. The through-power supply traction substation system includes: a plurality of traction substations 100, a plurality of transformers 200, a plurality of first single-phase converters 300, a plurality of second single-phase converters 400, and a plurality of three-phase converters 500.

[0053] Among them, Figure 1 As shown, adjacent traction substations 100 are connected via switches 40 ( Figure 1 1 shows a through-power supply traction substation system including two traction substations 100); Figure 2 As shown, a primary side of a transformer 200 is respectively connected in series between the traction bus 110 of each traction substation 100 and the traction substation feeder line 30, and the secondary side of each transformer 200 is respectively connected to the first port of a first single-phase converter 300; the second port of each first single-phase converter 300 is respectively connected to the first port of a three-phase converter 500; the traction bus 110 of each traction substation 100 is respectively connected to the first port of a second single-phase converter 400, and the second port of each second single-phase converter 400 is respectively connected to the first port of a three-phase converter 500; the second port of each three-phase converter 500 is respectively connected to a low-voltage side power distribution system 20.

[0054] The traction substation 100 herein is a substation dedicated to electric traction, which is configured to convert the electric energy transmitted from the power plant via the power transmission line into a voltage suitable for the rolling stock and distribute it to the contact network or contact rail.

[0055] When multiple traction substations 100 form a through power supply, multiple traction substations 100 connected to the same common connection point usually bring reverse power due to bus voltage differences. The reverse power may include ride-through power and regenerative power.

[0056] It should be understood that if the reverse power flow is not utilized in time, the reverse power flow may be fed back to the traction transformer feeder line 30 and have a negative impact on the power supply of the power grid and users through the traction transformer feeder line 30, thereby affecting the power supply stability.

[0057] The first terminal of the primary side of the transformer 200 is connected to the traction bus 110, and the other terminal of the primary side of the transformer 200 is connected to the traction transformer feeder line 30. The traction transformer feeder line 30 supplies power to the traction bus 110 through the traction transformer 200.

[0058] The first single-phase converter 300 is configured to adjust a first adjustment parameter of the traction bus 110 connected thereto. By adjusting the first adjustment parameter, the voltage difference between the traction buses 110 of two adjacent traction substations 100 can be reduced, thereby reducing the ride-through power generated by the two adjacent traction substations 100.

[0059] The number of the transformer 200, the first single-phase converter 300, the second single-phase converter 400 and the three-phase converter 500 can be determined according to the number of traction substations 100. Each traction substation 100 is equipped with at least one first single-phase converter 300, one second single-phase converter 400 and one three-phase converter 500.

[0060] The second single-phase converter 400 here is configured to switch between a rectification state and an inverter state. Wherein, when the second single-phase converter 400 is in a rectification state, the second single-phase converter 400 is configured to cooperate with the three-phase converter 500 to provide the reverse power flow of the traction substation 100 to the low-voltage side distribution system 20. When the traction transformer feeder line 30 cannot provide electric energy to the traction bus 110, the electric energy of the low-voltage side distribution system 20 can be delivered to the load in combination with the three-phase converter 500 when the second single-phase converter 400 is in an inverter state, so as to play an emergency power supply role.

[0061] Among them, the three-phase converter 500 is configured to switch between rectification state and inversion state, and the three-phase converter 500 is configured to cooperate with the second single-phase converter to provide the reverse power flow of the traction substation 100 to the low-voltage side distribution system 20, or to transmit the electric energy of the low-voltage side distribution system 20 to the load.

[0062] The switch 40 mentioned above may be a circuit breaker, an isolating switch 40 , a load switch 40 , etc. The switch 40 may be selected according to actual conditions.

[0063] The following takes the multi-variable power supply system as a bilateral power supply system as an example to further describe the working process of the through-power supply traction substation system in the embodiment of the present application:

[0064] If the bilateral power supply system includes a traction substation A and a traction substation B, the traction substation A and the traction substation B are connected through a switch 40, the primary side of the transformer A is connected in series between the traction bus A of the traction substation A and the traction transformer feeder line A, the secondary side of the transformer A is connected to the first port of the first single-phase converter A, the second port of the first single-phase converter A is connected to the first port of the three-phase converter A, the traction bus A is connected to the first port of the second single-phase converter A, the second port of the second single-phase converter A is connected to the first port of the three-phase converter A, and the second port of the three-phase converter A is connected to the low-voltage side distribution system A.

[0065] The primary side of transformer B is connected in series between the traction bus B of traction substation B and the traction transformer feeder line B, the secondary side of transformer B is connected to the first port of the first single-phase converter B, the second port of the first single-phase converter B is connected to the first port of the three-phase converter B, the traction bus B is connected to the first port of the second single-phase converter B, the second port of the second single-phase converter B is connected to the first port of the three-phase converter B, and the second port of the three-phase converter B is connected to the low-voltage side distribution system B.

[0066] When the switch 40 is closed, traction substation A and traction substation B are powered bilaterally.

[0067] When the voltage difference between the traction bus A and the traction bus B is large, the through power may be generated between the traction bus A and the traction bus B. In the case where the voltage difference between the traction bus A and the traction bus B is large, the intermediate voltage of the traction bus A and the traction bus B can be determined, and the first adjustment parameters of the first single-phase converter device A and the first single-phase converter device B are calculated respectively according to the intermediate voltage, and the first single-phase converter device A and the first single-phase converter device B are controlled to adjust according to the corresponding first adjustment parameters, so that the difference between the voltage value of the traction bus A superimposed on the first single-phase converter device A and the voltage value of the traction bus B superimposed on the first single-phase converter device B is reduced, thereby reducing the through power generated between the traction bus A and the traction bus B. If there is still through power after adjusting the first single-phase converter device A and the first single-phase converter device B, the through power can be rectified and inverted by the second single-phase converter device A and the three-phase converter device A and transmitted to the low-voltage side distribution system A for use by the low-voltage side distribution system A. And / or the cross-over power is rectified and inverted through the second single-phase converter B and the three-phase converter B and transmitted to the low-voltage side distribution system B for use by the low-voltage side distribution system B.

[0068] In the above implementation process, by setting the traction bus 110 to be connected with the transformer 200 and the first single-phase converter 300, when the cross-over power is formed between two adjacent traction substations 100, the voltage of the traction substation 100 connected thereto can be adjusted by the first single-phase converter 300, thereby reducing the voltage difference between the two adjacent traction substations 100, thereby reducing the generation of cross-over power, thereby reducing the capacity configuration of the cross-over power utilization device and reducing the system cost. At the same time, the cross-over power problem of the bilateral power supply system can be effectively solved to a certain extent, avoiding the reverse power transmission to the power system. In addition, by setting the second single-phase converter 400 and the three-phase converter 500, the second single-phase converter 400 and the three-phase converter 500 can transmit the cross-over power that still exists after adjustment to the low-voltage side distribution system 20 through rectification, inversion and other actions, for use by the low-voltage side distribution system 20, thereby improving the utilization rate of the cross-over power and reducing the power supply of the power supply system.

[0069] In one possible implementation, Figure 3 As shown, the through-power supply traction substation system further includes: a plurality of two-branch switches 700 ; each of the two-branch switches 700 includes a first branch contact 710 and a second branch contact 720 .

[0070] Among them, the first terminal of each first branch contact 710 is connected to the traction bus 110 of a traction substation 100, and the second terminal is connected to the traction transformer feeder line 30; the first terminal of each second branch contact 720 is connected to the traction transformer feeder line 30 and the second terminal of a first branch contact 710, and the second terminal is connected to one terminal of the primary side of a transformer 200; the other terminal of the primary side of each transformer 200 is connected to the first terminal of a first branch contact 710 and the traction bus 110 of the traction substation 100.

[0071] The first branch contact 710 and the second branch contact 720 described above work in a complementary conduction mode. That is, when the first branch contact 710 is in a conducting state, the second branch contact 720 is in a disconnected state. When the second branch contact 720 is in a conducting state, the first branch contact 710 is in a disconnected state.

[0072] It should be understood that by setting the first branch contact 710 and the second branch contact 720 to work in the complementary conduction mode, the transformer 200 and the first single-phase converter 300 can be put into the through-power supply traction substation system only when the through-power supply traction substation system is in an unloaded state. When the through-power supply traction substation system is in a non-unloaded state, the traction transformer feeder line 30 is directly connected to the traction bus 110, and at this time, the transformer 200 and the first single-phase converter 300 exit the through-power supply traction substation system.

[0073] In the above implementation process, by setting up two branch switches 700, and the first branch contact 710 and the second branch contact 720 of each two branch switch 700 working in the complementary conduction mode, the transformer 200 can be controlled to bypass and exit the through-power supply system under non-no-load conditions, thereby avoiding the power of the traction transformer feeder line 30 from flowing into the transformer 200 and the first single-phase converter 300, thereby reducing the capacity requirements of the transformer 200 and the first single-phase converter 300.

[0074] In a possible implementation, the through-power supply traction substation system further includes: a plurality of energy storage devices 600 .

[0075] The energy storage device 600 is connected to the second port of the first single-phase converter 300 and the second port of the second single-phase converter 400 .

[0076] The energy storage device 600 is configured to store surplus power of one or more traction substations 100 among the plurality of traction substations 100 ; the energy storage device 600 is also configured to supply power to the corresponding traction substation 100 via the second single-phase converter 400 .

[0077] Optionally, the remaining power includes one or more of remaining ride-through power and remaining regeneration power. The remaining power can be adjusted according to actual conditions.

[0078] The energy storage device 600 can store the reverse power flow generated by the traction substation 100 when the traction substation 100 generates a reverse power flow, and discharge the power to the traction substation 100 when the traction substation 100 is in a traction state, thereby supplying power to the equipment in the traction substation 100.

[0079] It can be understood that when the traction substation 100 generates a reverse current, if the reverse current cannot be used in time, the reverse current may be sent back to the power grid through the traction transformer feeder line 30, which has a negative impact on the power supply and users, and affects the stability of the power supply. When the traction substation 100 returns the power generation current, the power generation current can be transmitted to the low-voltage side distribution system 20 through the second single-phase converter 400 and the three-phase converter 500, so that the reverse current can be used by the equipment in the low-voltage side distribution system 20. If the reverse current is large, the equipment in the low-voltage side distribution system 20 may not be fully utilized, and when the energy storage device 600 meets the charging conditions, the energy storage device 600 can also be charged by the remaining reverse current. The reverse current is transmitted to the low-voltage side distribution system 20 and / or the energy storage device 600 for use through the second single-phase converter 400 and the three-phase converter 500, thereby reducing the reverse current to 0 as much as possible, and reducing the negative impact of the reverse current on the power grid through the traction transformer feeder line 30.

[0080] When the traction substation 100 does not generate reverse current and the energy storage device 600 meets the discharge conditions, the traction transformer feeder line 30 can supply power to the traction substation 100 while the energy storage device 600 supplies power to the traction substation 100, thereby reducing the power supply of the traction transformer feeder line 30 to the traction substation 100 and reducing the power supply cost.

[0081] In the above implementation process, by setting the energy storage device 600, when the low-voltage side power distribution system 20 cannot fully utilize the reverse power flow, the remaining power can be stored through the energy storage device 600, thereby reducing the reverse power flow in the system and reducing the negative impact of the reverse power flow on the power grid through the traction transformer feeder line 30. In addition, the power stored in the storage device can also be used to supply power to the traction substation 100, reducing the power supply amount of the traction transformer feeder line 30 to the traction substation 100, and reducing the power supply cost.

[0082] To facilitate understanding of this embodiment, the controller 600 that executes the reverse power flow processing method disclosed in the embodiment of the present application is introduced in detail below.

[0083] like Figure 4 , which is a block diagram of a controller 800. The controller 800 may include a memory 811, a processor 813, and a peripheral interface 815. A person skilled in the art may understand that Figure 4 The structure shown is only for illustration and does not limit the structure of the controller 800. For example, the controller 800 may also include Figure 4 More or fewer components as shown, or with Figure 4 Different configurations shown.

[0084] The controller 800 here can be a network server, a database server, etc., or a personal computer (PC), a tablet computer, a smart phone, a personal digital assistant (PDA), etc. The controller 800 can be selected according to actual conditions, and this application does not make specific restrictions.

[0085] The controller 800 can be connected to the traction substation, transformer, first single-phase converter, second single-phase converter and three-phase converter in the through-power supply traction substation system.

[0086] Exemplarily, the controller 800 may be connected to a traction substation and a first single-phase converter, determine the voltage of a traction bus in the traction substation, and calculate a first adjustment parameter of a corresponding first single-phase converter, and send the calculated first adjustment parameter to the corresponding first single-phase converter to control the first single-phase converter to operate according to the first adjustment parameter.

[0087] The controller 800 can also be connected to the second single-phase converter and the three-phase converter, and control the working states of the second single-phase converter and the three-phase converter according to the working conditions of the traction substation.

[0088] The controller 800 may also be connected to a storage device to control the controller 800 to charge or discharge.

[0089] The above-mentioned devices connected to the controller 800 are only exemplary. The devices connected to the controller 800 can be adjusted according to actual conditions, and this application does not impose any specific restrictions.

[0090] It can be understood that after obtaining the current information of the traction substation connected to the controller 800, the controller 800 can determine the operating condition of the traction substation based on the current information, and control the equipment connected to the controller 800 to switch to the working state corresponding to the operating condition.

[0091] The memory 811, processor 813 and peripheral interface 815 are directly or indirectly electrically connected to each other to achieve 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 processor 813 is used to execute the executable module stored in the memory 811.

[0092] The memory 811 may be, but is not limited to, a random access memory 811 (RAM), a read only memory 811 (ROM), a programmable read-only memory 811 (PROM), an erasable programmable read-only memory 811 (EPROM), an electrically erasable programmable read-only memory 811 (EEPROM), etc. The memory 811 is used to store programs, and the processor 813 executes the program after receiving the execution instruction. The method executed by the controller 800 defined by the process disclosed in any embodiment of the present application can be applied to the processor 813, or implemented by the processor 813.

[0093] The above-mentioned processor 813 may be an integrated circuit chip with signal processing capabilities. The above-mentioned processor 813 may be a general-purpose processor 813, including a central processing unit 813 (CPU), a network processor 813 (NP), etc.; it may also be a digital signal processor 813 (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The various methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor 813 may be a microprocessor 813 or the processor 813 may also be any conventional processor 813, etc.

[0094] The above-mentioned peripheral interface 815 couples various input / output devices to the processor 813 and the memory 811. In some embodiments, the peripheral interface 815, the processor 813 and the memory controller can be implemented in a single chip. In some other examples, they can be implemented by separate chips.

[0095] The controller 800 in this embodiment can be used to execute each step in each method provided in the embodiments of the present application. The implementation process of the power flow control method is described in detail below through several embodiments.

[0096] See also Figure 5, is a flow chart of the reverse power flow processing method provided in the embodiment of the present application. Figure 5 The specific process shown is described in detail.

[0097] Step S201, determining the operating condition of the through-power supply traction substation system according to the current information of one or more traction substations among the multiple traction substations.

[0098] Among them, adjacent traction substations among the multiple traction substations are connected through switches.

[0099] The current information here is the current of the traction feeder connected to the traction bus in the traction substation.

[0100] Optionally, the operating conditions may include no-load conditions, regeneration conditions, traction conditions, cross-zone operation, exit operation, etc., and the operating conditions may be set according to actual conditions.

[0101] It should be understood that when the switches between adjacent traction substations among the multiple traction substations are closed, the adjacent traction substations constitute bilateral power supply. When the adjacent traction substations are in bilateral power supply, the operating condition of the traction substation in bilateral power supply can be determined by acquiring the traction feeder in the traction substation in bilateral power supply.

[0102] In one embodiment, when the currents of the traction feeders of the two traction substations with bilateral power supply are both greater than 0, it is determined that the traction substation with bilateral power supply is in a traction condition. When the current of the traction feeder of one of the two traction substations with bilateral power supply is greater than 0 and the current of the traction feeder of the other traction substation is less than 0, it is determined that the traction substation with bilateral power supply is in a no-load condition. When the currents of the traction feeders of the two traction substations with bilateral power supply are both less than 0, it is determined that the traction substation with bilateral power supply is in a regeneration condition.

[0103] For example, if the traction substations in the through-power supply traction substation system are traction substation SS1 and traction substation SS2, and traction substation SS1 and traction substation SS2 are connected by a switch, the current of the traction feeder of traction substation SS1 is IF1, and the current of the traction feeder of traction substation SS2 is IF2. When the operating condition of the traction substation is the traction condition, IF1>0, IF2>0; when the operating condition of the traction substation is the no-load condition, IF1>0, IF2<0; when the operating condition of the traction substation is the regeneration condition, IF1<0, IF2<0.

[0104] Step S202: determine the adjustment strategy corresponding to the operating condition, and obtain the adjustment parameters required by the adjustment strategy.

[0105] Step S203: According to the adjustment strategy, corresponding equipment in one or more traction substations among the multiple traction substations is controlled to operate according to the adjustment parameters.

[0106] Each operating condition here is set with a corresponding adjustment strategy.

[0107] The above adjustment parameters are parameters of the equipment that need to be adjusted under the corresponding adjustment strategy. For example, under no-load conditions, the first single-phase converter needs to be adjusted. In some cases, the second single-phase converter and the three-phase converter can also be adjusted. At this time, the adjustment parameters are the adjustment parameters of the first single-phase converter, and / or the adjustment parameters of the second single-phase converter, and the adjustment parameters of the three-phase converter.

[0108] For another example, in the regeneration condition, the working states of the second single-phase converter and the three-phase converter need to be adjusted, and the adjustment parameters are the adjustment parameters of the second single-phase converter and the three-phase converter. The adjustment parameters can be adjusted according to a specific adjustment strategy.

[0109] Optionally, the adjustment parameter can be calculated in real time according to the operating conditions and the actual reverse power flow. The adjustment parameter can also be set in advance to a corresponding preset value according to the operating conditions. The method for determining the adjustment parameter can be selected according to actual conditions.

[0110] In the above implementation process, during the operation of the through-power supply traction substation system, the operating condition of the traction substation is first determined based on the current information of the traction substation, and the corresponding adjustment parameters are determined based on the operating condition of the traction substation to control the corresponding equipment to work according to the adjustment parameters. By adjusting the parameters of the corresponding equipment, the through-power supply generated by the traction substation can be reduced and the system stability can be improved. In addition, by determining the corresponding adjustment strategy according to the different operating conditions of the traction substation, the through-power supply traction substation system can be reused in multiple scenarios to improve the utilization rate of the through-power supply traction substation system.

[0111] In one possible implementation, the operating conditions include: no-load conditions; step S202, including: obtaining the ride-through power returned to one or more traction substations among the multiple traction substations; determining whether the ride-through power exceeds the ride-through power limit; when the ride-through power exceeds the ride-through power limit, determining a first adjustment parameter of a first single-phase converter connected to the traction substation whose ride-through power exceeds the ride-through power limit.

[0112] Step S203 includes: controlling a first single-phase converter connected to a traction substation whose ride-through power exceeds a ride-through power limit to operate according to a first adjustment parameter.

[0113] The first adjustment parameter is configured to reduce the ride-through power of one or more traction substations among the multiple traction substations.

[0114] Normally, the through-power traction substation system forms a parallel structure with the power grid through multiple traction substations. When the traction substation is unloaded, active power and current flow through the traction substation, which is called ride-through power. This ride-through power may affect the power flow distribution and power flow dispatching of the power system, and may also cause metering problems in the traction power supply system, resulting in economic losses for traction users.

[0115] The ride-through power limit here refers to the maximum power allowed by the traction substation. The ride-through power limit can be a fixed value set in advance, or a value calculated in real time based on the actual circuit parameters of the traction substation. The method for determining the ride-through power limit can be selected according to actual conditions.

[0116] The first adjustment parameter mentioned above refers to the adjustment voltage amplitude and the adjustment phase size of the first single-phase converter.

[0117] It should be understood that when the traction substation is in a no-load condition, if the voltage difference of the traction busbars of the through-powered traction substations exceeds the voltage difference threshold, then ride-through power may be generated in the through-powered traction substations. At this time, by adjusting the voltage amplitude and phase size of the first single-phase converter, the difference in the voltage amplitude and phase size of the traction busbars output by the through-powered traction substations can be reduced, thereby reducing the generation of ride-through power.

[0118] The phase size of the traction bus output is the phase size of the traction bus plus the phase size of the adjusted first single-phase converter connected to it. The voltage amplitude of the traction bus output is the voltage amplitude of the traction bus plus the voltage amplitude of the adjusted first single-phase converter connected to it.

[0119] In one embodiment, the voltage amplitude output by the traction bus of multiple traction substations with through-power supply is the average voltage amplitude of the traction bus of the multiple traction substations with through-power supply, and the phase size output by the traction bus of multiple traction substations with through-power supply is the average phase size of the traction bus of the multiple traction substations with through-power supply.

[0120] In another embodiment, the voltage amplitude outputted by the traction bus of the traction substation of the through-power supply is the voltage amplitude of the traction bus of the other traction substation of the through-power supply. The phase size of the traction bus of the traction substation of the through-power supply is the phase size of the traction bus of the other traction substation of the through-power supply.

[0121] After determining the phase size and voltage amplitude of the traction bus output, the adjusted voltage amplitude and adjusted phase size of the first single-phase converter connected to it can be directly calculated based on the phase size and voltage amplitude of the traction bus output and the actual phase size and voltage amplitude of the traction bus.

[0122] In the above implementation process, when the traction substation is in a no-load condition and the through-power traction substation in the through-power traction substation system generates through-power, by determining the first adjustment parameter of the first single-phase converter and controlling the operation of the first single-phase converter based on the first adjustment parameter, the voltage amplitude and phase size of the traction bus output connected to it can be adjusted by the first single-phase converter, thereby reducing the difference between the voltage amplitude and phase size of the traction bus output of the traction substation, so as to reduce the size of the through-power, reduce the configuration of the through-power utilization device capacity, and reduce the system cost. In addition, it can also effectively solve the through-power problem of the bilateral power supply system, reduce the through-power sent back to the power system, and improve the power supply stability of the power system.

[0123] In a possible implementation, when the ride-through power exceeds the ride-through power limit, a first adjustment parameter of a first single-phase converter connected to a traction substation whose ride-through power exceeds the ride-through power limit is determined, including: when the ride-through power exceeds the ride-through power limit, determining the traction substation that needs to perform parameter adjustment in the through-power traction substation system according to a priority rule; and calculating the first adjustment parameter of the first single-phase converter connected to the traction substation that needs to perform parameter adjustment according to a set rule.

[0124] The priority rule here is a rule set in advance for determining the traction substations that need parameter adjustment. The priority rule can be determined according to the magnitude relationship between the bus voltages of multiple traction substations in the through-power supply traction substation system. For example, when there are multiple traction substations whose first voltage difference between the bus voltage and the set voltage is within the first preset difference range in the through-power supply traction substation system, it can be determined that the other traction substations except the multiple traction substations whose first voltage difference is within the first preset difference range are traction substations that need parameter adjustment. For another example, when the voltage difference of the bus voltages of multiple traction substations in the through-power supply traction substation system is not within the preset difference range, it is determined that all traction substations in the traction substation need parameter adjustment. For another example, a preset bus voltage can also be set to determine that the traction substation with a bus voltage equal to the preset bus voltage or a difference within the preset range does not need parameter adjustment, and the other traction substations are traction substations that need parameter adjustment, etc. The priority rule can be set according to actual conditions.

[0125] The above-mentioned preset rule may be a rule that matches the priority rule, and the preset rule may also be a rule set in advance. For example, the preset rule may be that the bus voltage of the traction substation that needs to be adjusted and the average value of the bus voltages of all traction substations respectively determine the first adjustment parameter of the first single-phase converter connected to each traction substation that needs to be adjusted. The preset rule may also be that the bus voltage of the traction substation that needs to be adjusted and the average value of the bus voltages of multiple traction substations whose bus voltages are within a preset voltage range respectively determine the first adjustment parameter of the first single-phase converter connected to each traction substation that needs to be adjusted. The preset rule may be set according to actual needs.

[0126] For ease of understanding, several examples are given below to illustrate how to determine the traction substation that needs to be adjusted in parameters by using a priority rule, and the corresponding first adjustment parameter determination method:

[0127] Method 1: Determine the traction substations in the through-power supply traction substation system that need to adjust parameters according to the priority rule, including: when there are multiple traction substations in the through-power supply traction substation system whose first voltage difference between the bus voltage and the set voltage is within the first preset difference range, determine the other traction substations in the through-power supply traction substation system except for the multiple traction substations whose first voltage difference is within the first preset difference range as the traction substations that need to adjust parameters.

[0128] In one embodiment, the first adjustment parameter of the first single-phase converter connected to the traction substation that needs parameter adjustment is calculated according to a set rule, including: determining the first adjustment parameter of each first single-phase converter connected to the traction substation that needs parameter adjustment according to the bus voltage and the set voltage of the traction substation that needs parameter adjustment.

[0129] Among them, the first adjustment parameter is configured to reduce the difference between the bus voltage of the traction substation that needs parameter adjustment and the set voltage.

[0130] The set voltage here can be a voltage value set in advance according to the operation of the traction substation system to ensure the normal operation of the traction substation system. The set voltage can include one or more. The number of the set voltages can be selected according to actual conditions. For example, according to the different power supply peak and valley periods of the power supply system, a corresponding set voltage can be set for each period. The corresponding set voltage can also be set according to the date (for example, the set voltage for holidays such as National Day and May Day is different from the set voltage at other times), etc.

[0131] In one embodiment, if a first voltage difference between the bus voltage of the traction substation and the set voltage is within a first preset difference range, it can be determined that the bus voltage of the traction substation is approximately equal to the set voltage.

[0132] Method 2: Determine the traction substations in the through-power supply traction substation system that need to adjust parameters according to the priority rule, including: when there are multiple traction substations in the through-power supply traction substation system whose second voltage difference is within the second preset difference range, determine whether the bus voltages of the multiple traction substations whose second voltage difference is within the second preset difference range are within the preset voltage range; if the bus voltages of the multiple traction substations whose second voltage difference is within the second preset difference range are within the preset voltage range, determine that the other traction substations in the through-power supply traction substation system except the multiple traction substations whose second voltage difference is within the second preset difference range are the traction substations that need to adjust parameters.

[0133] In one embodiment, the first adjustment parameter of the first single-phase converter connected to the traction substation that needs parameter adjustment is calculated according to a set rule, including: determining the first adjustment parameter of each first single-phase converter connected to the traction substation that needs parameter adjustment based on the bus voltage of the traction substation that needs parameter adjustment and the second voltage difference of multiple traction substations within a second preset difference range.

[0134] The first adjustment parameter is configured to reduce the difference between the bus voltage of the traction substation requiring parameter adjustment and the bus voltages of multiple traction substations whose second voltage difference is within a second preset difference range.

[0135] The first preset difference range and the second preset difference range here may be the same or different, and the first preset difference range and the second preset difference range may be set according to actual conditions.

[0136] Method three: Determine the traction substations in the through-power supply traction substation system that need parameter adjustment according to the priority rule, including: if the bus voltages of multiple traction substations whose voltage difference is within the preset difference range are not within the preset voltage range, determine that all traction substations in the through-power supply traction substation system are traction substations that need parameter adjustment.

[0137] In one embodiment, the first adjustment parameter of the first single-phase converter connected to the traction substation that needs parameter adjustment is calculated according to a set rule, including: determining the first adjustment parameter of each first single-phase converter connected to the traction substation that needs parameter adjustment according to the bus voltage of the traction substation that needs parameter adjustment and the average value of the bus voltage.

[0138] Among them, the first adjustment parameter is configured to reduce the difference between the bus voltage of the traction substation and the average value of the bus voltage.

[0139] Method 4: Determine the traction substations that need to adjust parameters in the through-feed traction substation system according to the priority rule, including:

[0140] When the voltage differences of the bus voltages of multiple traction substations in the through-feed traction substation system are not within the preset difference range, calculating the average bus voltage of multiple traction substations whose bus voltages are within the preset voltage range;

[0141] Determine that the traction substation whose bus voltage is different from the average bus voltage is the traction substation that needs parameter adjustment;

[0142] Calculating a first adjustment parameter of a first single-phase converter connected to a traction substation that needs to be adjusted according to a set rule includes:

[0143] The first adjustment parameter of the first single-phase converter connected to each traction substation that needs parameter adjustment is determined based on the bus voltage of the traction substation that needs parameter adjustment and the average value of the bus voltage; wherein the first adjustment parameter is configured to reduce the difference between the bus voltage of the traction substation and the average value of the bus voltage.

[0144] The above-mentioned determination of the traction substation that needs parameter adjustment by priority rules and the corresponding first adjustment parameter determination method are only exemplary. The determination of the traction substation that needs parameter adjustment by priority rules and the corresponding first adjustment parameter determination method can be adjusted according to actual conditions.

[0145] The preset difference range here is a smaller bus voltage difference range. When the voltage difference of the bus voltages of the traction substation is within the preset difference range, the bus voltages of the traction substation can be approximately the same.

[0146] The above preset voltage range is the voltage range allowed for the normal operation of the traction substation. When the bus voltage of the traction substation is not within the preset voltage range, it can be approximately considered that the bus voltage of the traction substation may be in an abnormal working state.

[0147] In the above implementation process, by setting a priority rule for determining the traction substations that need to be adjusted, as few traction substations as possible can be determined for parameter adjustment according to demand, reducing the number of traction substations that need to be adjusted, and improving the adjustment efficiency. In a possible implementation, after controlling the first single-phase converter connected to the traction substation whose ride-through power exceeds the ride-through power limit to work according to the first adjustment parameter, the method also includes: when one or more traction substations among the multiple traction substations still have residual ride-through power: controlling the second single-phase converter to be in a rectification state, and controlling the three-phase converter to be in an inverter state; transmitting the residual ride-through power after rectification by the second single-phase converter and inversion by the three-phase converter to the low-voltage side distribution system.

[0148] The remaining ride-through power after rectification by the second single-phase converter and inversion by the three-phase converter is configured to be used by the low-voltage side power distribution system.

[0149] The residual ride-through power here refers to the ride-through power generated by the traction substation after being adjusted by the first single-phase converter.

[0150] It should be understood that although the first single-phase converter can adjust the voltage output by the traction bus of the traction substation by working according to the first adjustment parameter, since the power supply situation in the system changes in real time and may be limited by the limit of the capacity of the first single-phase converter itself, it is still difficult for the output voltage information of the traction bus of the through-power supply to be completely the same when the voltage information is adjusted by the first single-phase converter, that is, it is difficult to completely avoid the generation of ride-through power.

[0151] When there is surplus ride-through power in the traction substation, the surplus ride-through power can be utilized to avoid the surplus ride-through power being fed back to the three-phase system.

[0152] At this time, the second single-phase converter can be controlled to be in a rectification state, and the remaining ride-through power can be rectified and transmitted to the three-phase converter. The three-phase converter will invert the rectified remaining ride-through power and transmit the inverted remaining ride-through power to the low-voltage side distribution system so that the electrical equipment in the low-voltage side distribution system can use the remaining ride-through power.

[0153] In the above implementation process, after adjustment by the first single-phase converter, if there is still residual ride-through power in the traction substation, the residual ride-through power can be rectified and inverted and then transmitted to the low-voltage side distribution system by controlling the corresponding working states of the second single-phase converter and the three-phase converter, so that the residual ride-through power can be used by the electrical equipment in the low-voltage side distribution system, thereby improving the utilization rate of the ride-through power. In addition, by utilizing the residual ride-through power through the low-voltage side distribution system, the residual ride-through power in the system can be reduced, thereby reducing the ride-through power returned to the three-phase system, reducing the impact of the ride-through power on the power grid through the traction transformer feeder line, and improving the power supply stability and safety of the power grid.

[0154] In one possible implementation, the operating conditions include: regeneration conditions; step S202, including: obtaining the regeneration power in one or more traction substations among the multiple traction substations; when the regeneration power is less than or equal to the power of the three-phase converter: controlling the second single-phase converter to be in a rectification state, and controlling the three-phase converter to be in an inversion state; transmitting the regeneration power after rectification by the second single-phase converter and inversion by the three-phase converter to the low-voltage side distribution system.

[0155] The regenerative power after rectification by the second single-phase converter and inversion by the three-phase converter is configured to be used by the low-voltage side power distribution system.

[0156] The regenerative power here refers to the power returned by the traction substation under regenerative conditions. The regenerative condition refers to the process in which the traction motor's motor condition is changed to a generator condition when the electric locomotive in the traction substation is decelerating or braking, converting the train's kinetic energy into electrical energy, and then feeding it back to the three-phase power supply system through the traction substation. If the regenerative power is returned to the three-phase system, it may cause the three-phase system to reverse power transmission, affecting the safety and stability of the three-phase system power supply.

[0157] When the traction substation is in a regenerative condition, the second single-phase converter of the traction substation in the regenerative condition can be controlled to be in a rectification state, and the regenerative power is rectified and transmitted to the three-phase converter. The three-phase converter then inverts the rectified regenerative power and transmits the inverted regenerative power to the low-voltage side distribution system for use by the low-voltage side distribution system.

[0158] In one embodiment, when the regenerative power is less than the power of the three-phase converter: the power transmitted to the low-voltage side power distribution system through the second single-phase converter and the three-phase converter is equal to the regenerative power.

[0159] In the above implementation process, by controlling the corresponding working states of the second single-phase converter and the three-phase converter, the regenerative power is rectified and inverted and then transmitted to the low-voltage side distribution system, so that the electrical equipment in the low-voltage side distribution system can use the regenerative power, thereby improving the utilization rate of the regenerative power. In addition, by using the regenerative power through the low-voltage side distribution system, the regenerative power in the system can be reduced, thereby reducing the regenerative power returned to the three-phase system, reducing the impact of the regenerative power on the power grid through the traction transformer feeder line, and improving the power supply stability and safety of the power grid.

[0160] In a possible implementation, the method also includes: when the regenerative power is greater than or equal to the power of the three-phase converter: controlling the second single-phase converter to be in a rectification state, and controlling the three-phase converter to be in an inversion state; transmitting the regenerative power rectified by the second single-phase converter and inverted by the three-phase converter to the low-voltage side power distribution system; and controlling the energy storage device to store the remaining regenerative power.

[0161] Among them, the regenerative power transmitted to the low-voltage side distribution system is equal to the power of the three-phase converter.

[0162] In one embodiment, when the regenerative power is greater than or equal to the power of the three-phase converter and less than or equal to the sum of the power of the three-phase converter and the energy storage device, the second single-phase converter is controlled to be in a rectifying state, and the three-phase converter is controlled to be in an inverting state, so that the regenerative power transmitted to the low-voltage side power distribution system by the second single-phase converter and the three-phase converter is equal to the power of the three-phase converter. At the same time, the energy storage device is controlled to be charged according to the charging power being the difference between the regenerative power and the power of the three-phase converter, and the remaining regenerative power is stored.

[0163] When the regenerative power is greater than the sum of the powers of the three-phase converter and the energy storage device, the second single-phase converter is controlled to be in a rectifying state, and the three-phase converter is controlled to be in an inverting state, so that the regenerative power transmitted to the low-voltage side power distribution system through the second single-phase converter and the three-phase converter is equal to the power of the three-phase converter. At the same time, the energy storage device is controlled to be charged according to the power of the energy storage device, and the remaining regenerative power is stored.

[0164] In the above implementation process, when the regenerative power is greater than or equal to the power of the three-phase converter, the remaining regenerative power used by the low-voltage side distribution system can be sent to the energy storage device to charge the energy storage device, and the remaining regenerative power is further consumed by the energy storage device to further reduce the regenerative power returned to the three-phase system, reduce the impact of the regenerative power on the power grid through the traction transformer feeder line, and improve the power supply stability and safety of the power grid.

[0165] In one possible implementation, the operating conditions include: traction conditions; step S202, including: when the traction power is less than the power of the energy storage device, controlling the energy storage device to discharge according to the traction power, and controlling the second single-phase converter device to be in an inverter state; when the traction power is greater than or equal to the power of the energy storage device, controlling the energy storage device to discharge according to the power of the energy storage device, and controlling the second single-phase converter device to be in an inverter state.

[0166] The power converted by the second single-phase converter is configured to be used by traction equipment in one or more traction substations among the multiple traction substations.

[0167] The traction power here refers to the power used to pull equipment or carriages when the train is running. The traction condition refers to the working state of the traction system providing traction power for the train.

[0168] The second single-phase converter is configured to invert the electric energy in the energy storage device into alternating current through the second single-phase converter for use by traction equipment in the traction substation.

[0169] In the above implementation process, the power supplied to the traction substation is determined based on the relationship between the traction power and the power of the energy storage device. That is, within the allowable range of the power of the energy storage device and the power of the traction substation, the traction substation is supplied with power at a relatively small power supply, so that as much electric energy stored in the energy storage device as possible can be transmitted to the traction substation under the premise of ensuring line safety, thereby reducing the electric energy that the three-phase system needs to provide to the traction substation and reducing electricity costs.

[0170] In a possible implementation, the operating condition includes: inter-zone operation; step S202 includes: controlling the second single-phase converter to generate a reactive current whose phase exceeds the voltage phase of the traction substation connected thereto by 90°.

[0171] Wherein the reactive current is configured to support a voltage in one or more traction substations of the plurality of traction substations.

[0172] The cross-zone operation here means that one or more traction substations in the through-power supply traction substation system are taken out of operation.

[0173] In one embodiment, in the inter-zone operation condition, the first single-phase converter device, the three-phase converter device and the energy storage device are in a standby mode.

[0174] In the above implementation process, under the inter-regional operation condition, reactive power is generated by the second single-phase converter, which can reduce the power supply difference between traction substations in different areas and improve the power supply stability of the traction substations.

[0175] In a possible implementation, the operating condition includes: exiting operation; step S202 includes: controlling the three-phase converter to be in a rectifying state; and controlling the second single-phase converter to be in an inverting state.

[0176] Among them, the electric energy in the low-voltage side distribution system after rectification by the three-phase converter and inversion by the second single-phase converter is configured as an emergency power supply for traction equipment of a plurality of traction substations that have been shut down.

[0177] The decommissioning here refers to the decommissioning of some traction substations in the through-power supply traction substation system.

[0178] In the above implementation process, when the traction substation is in an out-of-operation condition, the electric energy in the low-voltage side distribution system is rectified and inverted through a three-phase converter and a second single-phase converter and then transmitted to the traction equipment in the traction substation for use by the traction equipment. This can provide emergency rescue when an emergency occurs in the traction substation, and ensure the safety and stability of the operation of the traction equipment in the traction substation.

[0179] In a possible implementation, before step S201, the method also includes: calculating the average bus voltage of two adjacent traction substations; calculating the working voltage of the corresponding first single-phase converter device according to the average bus voltage and the bus voltage of each traction substation; controlling each first single-phase converter device to operate according to the corresponding working voltage; and controlling the switch to close when it is determined that the difference between the superimposed voltage of two adjacent traction substations and the average bus voltage is within a preset range.

[0180] The difference between a superimposed voltage obtained by superimposing the working voltage of the first single-phase converter and the bus voltage of the corresponding traction substation and an average value of the bus voltage is within a preset range.

[0181] The voltage average value here may include a voltage amplitude average value and a phase angle average value.

[0182] In one embodiment, the calculation of the average bus voltage of two adjacent traction substations may be achieved by the following formula:

[0183]

[0184] Then the working voltage of the first single-phase converter corresponding to the traction substation SS1 can be realized by the following formula:

[0185]

[0186] The working voltage of the first single-phase converter corresponding to the traction substation SS2 can be realized by the following formula:

[0187]

[0188]

[0189] Where U1 is the amplitude of the bus voltage of traction substation SS1, U2 is the amplitude of the bus voltage of traction substation SS2, Ψ1 is the phase of the bus voltage of traction substation SS1, Ψ2 is the phase of the bus voltage of traction substation SS2, U a is the average amplitude, Ψ a is the average phase.

[0190] If the difference between the superimposed voltage of the two adjacent traction substations and the average value of the bus voltage is within the preset range, it can be determined that the two adjacent traction substations meet the closing condition. At this time, closing the switch can form a bilateral power supply.

[0191] In the above implementation process, before closing the switch, it is first calculated whether the traction substation meets the closing conditions. When it is determined that the traction substation meets the closing conditions, the switch is closed to form bilateral power supply, which can improve the stability of the traction substation.

[0192] Based on the same application concept, the embodiment of the present application also provides a power utilization device corresponding to the reverse power flow processing method. Since the principle of solving the problem by the device in the embodiment of the present application is similar to that of the aforementioned reverse power flow processing method embodiment, the implementation of the device in this embodiment can refer to the description in the embodiment of the above method, and the repeated parts will not be repeated.

[0193] See also Figure 6 , is a functional module diagram of a power utilization device provided in an embodiment of the present application. Each module in the power utilization device in this embodiment is used to execute each step in the above method embodiment. The power utilization device includes a determination module 910, an acquisition module 920, and a control module 930; wherein,

[0194] The determination module 910 is used to determine the operating condition of the through-power supply traction substation system according to the current information of one or more traction substations among the multiple traction substations.

[0195] The acquisition module 920 is used to determine the adjustment strategy corresponding to the operating condition and obtain the adjustment parameters required by the adjustment strategy.

[0196] The control module 930 is used to control corresponding equipment in one or more traction substations among the multiple traction substations to operate according to the adjustment parameters according to the adjustment strategy.

[0197] In a possible implementation, the acquisition module 920 is also used to: obtain the ride-through power returned to one or more traction substations among the multiple traction substations; determine whether the ride-through power exceeds the ride-through power limit; and when the ride-through power exceeds the ride-through power limit, determine the first adjustment parameter of the first single-phase converter connected to the traction substation whose ride-through power exceeds the ride-through power limit.

[0198] In a possible implementation, the control module 930 is specifically used to: control the first single-phase converter connected to the traction substation whose ride-through power exceeds the ride-through power limit to operate according to the first adjustment parameter; wherein the first adjustment parameter is configured to reduce the ride-through power of one or more traction substations among the multiple traction substations.

[0199] In a possible implementation, the acquisition module 920 is specifically used to: when the ride-through power exceeds the ride-through power limit, determine the traction substation in the through-power supply traction substation system that needs to adjust parameters according to a priority rule; calculate the first adjustment parameter of the first single-phase converter connected to the traction substation that needs to adjust parameters according to the set rules.

[0200] In a possible implementation manner, the acquisition module 920 is specifically used to: when there are multiple traction substations in the through-power supply traction substation system whose first voltage difference between the bus voltage and the set voltage is within the first preset difference range, determine that other traction substations in the through-power supply traction substation system, except for the multiple traction substations whose first voltage difference is within the first preset difference range, are traction substations that need to be adjusted in parameters;

[0201] In a possible implementation, the acquisition module 920 is further specifically used to: determine the first adjustment parameter of the first single-phase converter connected to each traction substation that needs parameter adjustment according to the bus voltage of the traction substation that needs parameter adjustment and the set voltage; wherein the first adjustment parameter is configured to reduce the difference between the bus voltage of the traction substation that needs parameter adjustment and the set voltage.

[0202] In a possible implementation, the acquisition module 920 is specifically used to: if the bus voltages of multiple traction substations whose voltage differences are within a preset difference range are not within a preset voltage range, determine that all traction substations in the through-power supply traction substation system are traction substations that require parameter adjustment.

[0203] In a possible implementation, the acquisition module 920 is further specifically used to: determine the first adjustment parameter of the first single-phase converter connected to each traction substation that needs to undergo parameter adjustment according to the bus voltage of the traction substation that needs to undergo parameter adjustment and the average value of the bus voltage; wherein the first adjustment parameter is configured to reduce the difference between the bus voltage of the traction substation and the average value of the bus voltage.

[0204] In a possible implementation, the acquisition module 920 is specifically used to: calculate the average bus voltage of multiple traction substations whose bus voltages are within a preset voltage range when the bus voltages of multiple traction substations in the through-power supply traction substation system are different; and determine that the traction substation whose bus voltage is different from the average bus voltage is a traction substation that requires parameter adjustment.

[0205] In a possible implementation, the acquisition module 920 is further specifically used to: determine the first adjustment parameter of the first single-phase converter connected to each traction substation that needs to undergo parameter adjustment according to the bus voltage of the traction substation that needs to undergo parameter adjustment and the average value of the bus voltage; wherein the first adjustment parameter is configured to reduce the difference between the bus voltage of the traction substation and the average value of the bus voltage.

[0206] In one possible implementation, the acquisition module 920 is specifically used to: when there is residual ride-through power in one or more traction substations among the multiple traction substations: control the second single-phase converter device to be in a rectification state, and control the three-phase converter device to be in an inversion state; transmit the residual ride-through power after rectification by the second single-phase converter device and inversion by the three-phase converter device to the low-voltage side power distribution system; wherein the residual ride-through power after rectification by the second single-phase converter device and inversion by the three-phase converter device is configured for use by the low-voltage side power distribution system.

[0207] In a possible implementation, the acquisition module 920 is also used to: acquire the regenerative power in one or more traction substations among the multiple traction substations; when the regenerative power is less than or equal to the power of the three-phase converter: control the second single-phase converter to be in a rectification state, and control the three-phase converter to be in an inversion state; transmit the regenerative power rectified by the second single-phase converter and inverted by the three-phase converter to the low-voltage side power distribution system; wherein the regenerative power rectified by the second single-phase converter and inverted by the three-phase converter is configured for use by the low-voltage side power distribution system.

[0208] In a possible implementation, the acquisition module 920 is specifically used to: when the regenerative power is greater than or equal to the power of the three-phase converter: control the second single-phase converter to be in a rectification state, and control the three-phase converter to be in an inversion state; transmit the regenerative power rectified by the second single-phase converter and inverted by the three-phase converter to the low-voltage side power distribution system; wherein the regenerative power transmitted to the low-voltage side power distribution system is equal to the power of the three-phase converter; and control the energy storage device to store the remaining regenerative power.

[0209] In a possible implementation, the acquisition module 920 is further used to: when the traction power is less than the power of the energy storage device, control the energy storage device to discharge according to the traction power, and control the second single-phase converter device to be in an inverter state; when the traction power is greater than or equal to the power of the energy storage device, control the energy storage device to discharge according to the power of the energy storage device, and control the second single-phase converter device to be in an inverter state; wherein the power after inversion by the second single-phase converter device is configured to be used by traction equipment in one or more traction substations among a plurality of traction substations.

[0210] In a possible implementation, the acquisition module 920 is further used to: obtain the voltage phase of a traction substation connected to one or more traction substations among the multiple traction substations; control the second single-phase converter to generate a reactive current whose phase exceeds the voltage phase of the traction substation connected to it by 90°; wherein the reactive current is configured to support the voltage in one or more traction substations among the multiple traction substations.

[0211] In a possible implementation, the acquisition module 920 is also used to: control the three-phase converter to be in a rectification state; control the second single-phase converter to be in an inversion state; wherein the electric energy in the low-voltage side distribution system after rectification by the three-phase converter and inversion by the second single-phase converter is configured as an emergency power supply for use by traction equipment of a traction substation that has been shut down among multiple traction substations.

[0212] In one possible implementation, the power utilization device includes a calculation module, which is used to: calculate the average bus voltage of two adjacent traction substations; calculate the working voltage of the corresponding first single-phase converter according to the average bus voltage and the bus voltage of each traction substation; control each first single-phase converter to operate according to the corresponding working voltage; wherein the difference between the superimposed voltage after the working voltage of the first single-phase converter and the bus voltage of the corresponding traction substation and the average bus voltage is within a preset range; when it is determined that the difference between the superimposed voltage of two adjacent traction substations and the average bus voltage is within the preset range, control the switch to close.

[0213] In addition, an embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the reverse power flow processing method in the above method embodiment are executed.

[0214] The computer program product of the reverse power flow processing method provided in the embodiment of the present application includes a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the steps of the reverse power flow processing method in the above method embodiment. For details, please refer to the above method embodiment, which will not be repeated here.

[0215] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0216] In addition, the functional modules in the various embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.

[0217] If the function is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a disk or an optical disk. It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variation thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus. In the absence of more restrictions, the elements defined by the sentence "includes..." do not exclude the presence of other identical elements in the process, method, article or apparatus that includes the elements.

[0218] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0219] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A reverse power flow processing method, characterized in that: Applicable to a through-power supply traction substation system; wherein the through-power supply traction substation system comprises a plurality of traction substations, and two adjacent traction substations are connected via a switch; The method comprises: Determining the operating condition of the through-feed traction substation system according to current information of one or more traction substations among the plurality of traction substations; Determine an adjustment strategy corresponding to the operating condition, and obtain adjustment parameters required by the adjustment strategy; According to the adjustment strategy, corresponding equipment in one or more traction substations among the plurality of traction substations is controlled to operate according to the adjustment parameters.

2. The method according to claim 1, characterized in that in, The through-feed traction substation system further includes: a first single-phase converter and a transformer; a primary side of the transformer is connected in series between the traction bus of each traction substation and the traction transformer feeder line, and each secondary side of the transformer is connected to a first port of the first single-phase converter, and each second port of the first single-phase converter is connected to a low-voltage side power distribution system; The operating condition includes: no-load condition, and the adjustment parameter includes a first adjustment parameter; The determining the adjustment strategy corresponding to the operating condition and obtaining the adjustment parameters required by the adjustment strategy includes: obtaining ride-through power returned to one or more traction substations among a plurality of traction substations; Determining whether the ride-through power exceeds a ride-through power limit; In the case where the ride-through power exceeds the ride-through power limit, determining a first adjustment parameter of the first single-phase converter connected to the traction substation whose ride-through power exceeds the ride-through power limit; According to the adjustment strategy, controlling corresponding equipment in one or more traction substations among the plurality of traction substations to operate according to the adjustment parameters includes: Controlling the first single-phase converter connected to the traction substation whose ride-through power exceeds the ride-through power limit to operate according to the first adjustment parameter; The first adjustment parameter is configured to reduce the ride-through power of one or more traction substations among the multiple traction substations.

3. The method according to claim 2, characterized in that When the ride-through power exceeds the ride-through power limit, determining the first adjustment parameter of the first single-phase converter connected to the traction substation whose ride-through power exceeds the ride-through power limit includes: In the case where the ride-through power exceeds the ride-through power limit, determining, according to a priority rule, a traction substation in the through-power traction substation system that needs to have its parameters adjusted; The first adjustment parameter of the first single-phase converter connected to the traction substation requiring parameter adjustment is calculated according to a set rule.

4. The method according to claim 3, characterized in that: The step of determining the traction substation in the through-feed traction substation system that needs to adjust parameters according to the priority rule includes: In the case where there are multiple traction substations in the through-feed traction substation system whose first voltage differences between the bus voltage and the set voltage are within the first preset difference range, determining that other traction substations in the through-feed traction substation system, except for the multiple traction substations whose first voltage differences are within the first preset difference range, are traction substations that need to be adjusted in parameters; The calculating, according to a set rule, the first adjustment parameter of the first single-phase converter connected to the traction substation that needs to be adjusted in parameters includes: The first adjustment parameter of the first single-phase converter connected to each traction substation that needs parameter adjustment is determined based on the bus voltage of the traction substation that needs parameter adjustment and the set voltage; wherein the first adjustment parameter is configured to reduce the difference between the bus voltage of the traction substation that needs parameter adjustment and the set voltage.

5. The method according to claim 3, characterized in that: The step of determining the traction substation in the through-feed traction substation system that needs to adjust parameters according to the priority rule includes: If the bus voltages of the multiple traction substations whose voltage differences are within the preset difference range are not within the preset voltage range, it is determined that all traction substations in the through-feed traction substation system are traction substations that need parameter adjustment; The calculating, according to a set rule, the first adjustment parameter of the first single-phase converter connected to the traction substation that needs to be adjusted in parameters includes: The first adjustment parameter of the first single-phase converter connected to each traction substation that needs to be adjusted in parameters is determined according to the bus voltage of the traction substation that needs to be adjusted in parameters and the average value of the bus voltage; wherein the first adjustment parameter is configured to reduce the difference between the bus voltage of the traction substation and the average value of the bus voltage.

6. The method according to claim 3, characterized in that The step of determining the traction substation in the through-feed traction substation system that needs to adjust parameters according to the priority rule includes: When the voltage differences of the bus voltages of the plurality of traction substations in the through-feed traction substation system are not within the preset difference range, calculating the average bus voltage of the plurality of traction substations whose bus voltages are within the preset voltage range; Determine that a traction substation whose bus voltage is different from the average bus voltage is a traction substation that needs parameter adjustment; The calculating, according to a set rule, the first adjustment parameter of the first single-phase converter connected to the traction substation that needs to be adjusted in parameters includes: The first adjustment parameter of the first single-phase converter connected to each traction substation that needs to be adjusted in parameters is determined according to the bus voltage of the traction substation that needs to be adjusted in parameters and the average value of the bus voltage; wherein the first adjustment parameter is configured to reduce the difference between the bus voltage of the traction substation and the average value of the bus voltage.

7. The method according to claim 2, characterized in that in, The through-feed traction substation system further includes: a second single-phase converter and a three-phase converter; the traction busbar of each traction substation is respectively connected to a first port of the second single-phase converter, the second port of each second single-phase converter is respectively connected to a first port of the three-phase converter, and the second port of each three-phase converter is respectively connected to a low-voltage side power distribution system; After the first single-phase converter connected to the traction substation controlling the ride-through power to exceed the ride-through power limit operates according to the first adjustment parameter, the method further includes: When there is residual ride-through power in one or more traction substations among the multiple traction substations: Controlling the second single-phase converter to be in a rectifying state, and controlling the three-phase converter to be in an inverting state; Transmitting the remaining ride-through power after rectification by the second single-phase converter and inversion by the three-phase converter to the low-voltage side power distribution system; The remaining ride-through power after rectification by the second single-phase converter and inversion by the three-phase converter is configured to be used by the low-voltage side power distribution system.

8. The method according to claim 1, characterized in that: in, The through-feed traction substation system further includes: a second single-phase converter and a three-phase converter; the traction busbar of each traction substation is respectively connected to a first port of the second single-phase converter, the second port of each second single-phase converter is respectively connected to a first port of the three-phase converter, and the second port of each three-phase converter is respectively connected to a low-voltage side power distribution system; The operating conditions include: regeneration conditions; The determining the adjustment strategy corresponding to the operating condition and obtaining the adjustment parameters required by the adjustment strategy includes: obtaining regenerative power in one or more traction substations of the plurality of traction substations; When the regenerative power is less than or equal to the power of the three-phase converter: Controlling the second single-phase converter to be in a rectifying state, and controlling the three-phase converter to be in an inverting state; Transmitting the regenerative power rectified by the second single-phase converter and inverted by the three-phase converter to the low-voltage side power distribution system; The regenerative power rectified by the second single-phase converter and inverted by the three-phase converter is configured to be used by the low-voltage side power distribution system.

9. The method according to claim 8, characterized in that in, The through-feed traction substation system further includes: an energy storage device; the energy storage device is connected to the second port of the second single-phase converter; The method further comprises: When the regenerative power is greater than or equal to the power of the three-phase converter: Controlling the second single-phase converter to be in a rectifying state, and controlling the three-phase converter to be in an inverting state; Transmitting the regenerative power rectified by the second single-phase converter and inverted by the three-phase converter to the low-voltage side power distribution system; wherein the regenerative power transmitted to the low-voltage side power distribution system is equal to the power of the three-phase converter; The energy storage device is controlled to store the remaining regenerative power.

10. The method according to claim 1, characterized in that in, The through-feed traction substation system further includes: an energy storage device and a second single-phase converter; the traction busbar in each traction substation is respectively connected to a first port of the second single-phase converter, and the second port of each second single-phase converter is respectively connected to one of the energy storage devices; The operating conditions include: traction conditions; The determining the adjustment strategy corresponding to the operating condition and obtaining the adjustment parameters required by the adjustment strategy includes: When the traction power is less than the power of the energy storage device, the energy storage device is controlled to discharge according to the traction power, and the second single-phase converter is controlled to be in an inverter state; When the traction power is greater than or equal to the power of the energy storage device, the energy storage device is controlled to discharge according to the power of the energy storage device, and the second single-phase converter is controlled to be in an inverter state; The power converted by the second single-phase converter is configured to be used by traction equipment in one or more traction substations among the multiple traction substations.

11. The method according to claim 1, characterized in that in, The through-feed traction substation system further includes: a second single-phase converter; the traction busbar of each traction substation is respectively connected to a first port of the second single-phase converter; The operation conditions include: inter-region operation, wherein the inter-region operation is to shut down one or more traction substations in the through-power supply traction substation system; The determining the adjustment strategy corresponding to the operating condition and obtaining the adjustment parameters required by the adjustment strategy includes: Controlling the second single-phase converter to generate a reactive current whose phase exceeds the voltage phase of the traction substation connected thereto by 90°; Wherein, the reactive current is configured to support the voltage in one or more traction substations among the plurality of traction substations.

12. The method according to claim 1, characterized in that in, The through-feed traction substation system further includes: a second single-phase converter and a three-phase converter; the traction busbar of each traction substation is respectively connected to a first port of the second single-phase converter, the second port of each second single-phase converter is respectively connected to a first port of the three-phase converter, and the second port of each three-phase converter is respectively connected to a low-voltage side power distribution system; The operation conditions include: exiting operation, wherein the exiting operation is that some traction substations in the through-power supply traction substation system exit operation; The determining the adjustment strategy corresponding to the operating condition and obtaining the adjustment parameters required by the adjustment strategy includes: Controlling the three-phase converter to be in a rectifying state; Controlling the second single-phase converter to be in an inverter state; Among them, the electric energy in the low-voltage side power distribution system after rectification by the three-phase converter and inversion by the second single-phase converter is configured as an emergency power supply for traction equipment of one or more traction substations in the traction substations that have been shut down.

13. The method according to claim 1, characterized in that The through-feed traction substation system further includes: a transformer and a first single-phase converter; a primary side of the transformer is connected in series between the traction busbar of each traction substation and the traction transformer feeder line, and a first port of the first single-phase converter is connected to the secondary side of each transformer; Before determining the operating condition of the through-feed traction substation system according to the current information of one or more traction substations among the plurality of traction substations, the method further includes: Calculate the average bus voltage of two adjacent traction substations; Calculating the operating voltage of the corresponding first single-phase converter device according to the bus voltage average value and the bus voltage of each traction substation; Controlling each first single-phase converter to operate at a corresponding working voltage; wherein a difference between a superimposed voltage obtained by superimposing the working voltage of the first single-phase converter and the bus voltage of the corresponding traction substation and an average value of the bus voltage is within a preset range; When it is determined that the differences between the superimposed voltages of two adjacent traction substations and the average value of the bus voltage are both within a preset range, the switch is controlled to be closed.

14. A through-power supply traction substation system, characterized in that: The through-feed traction substation system is used to execute the method described in any one of claims 1 to 13, and the system comprises: a plurality of traction substations, a plurality of transformers, a plurality of first single-phase converters, a plurality of second single-phase converters, and a plurality of three-phase converters; Adjacent traction substations are connected via switches; A primary side of the transformer is connected in series between the traction busbar of each traction substation and the traction transformer feeder line, and a secondary side of each transformer is connected to a first port of the first single-phase converter. The second port of each of the first single-phase converter devices is respectively connected to the first port of one of the three-phase converter devices; The traction busbar of each traction substation is respectively connected to the first port of one of the second single-phase converters, and the second port of each of the second single-phase converters is respectively connected to the first port of one of the three-phase converters; The second port of each of the three-phase converters is respectively connected to a low-voltage side power distribution system.

15. The system according to claim 14, characterized in that Also includes: A plurality of two-branch switches; each of the two-branch switches comprises a first branch contact and a second branch contact; The first terminal of each of the first branch contacts is connected to a traction busbar of the traction substation, and the second terminal is connected to a traction transformer feeder line; the first terminal of each of the second branch contacts is connected to the traction transformer feeder line and a second terminal of the first branch contact, and the second terminal is connected to a terminal of the primary side of the transformer; the other terminal of the primary side of each of the transformers is connected to a first terminal of the first branch contact and a traction busbar of the traction substation; The first branch contact and the second branch contact operate in a complementary conduction mode.

16. The system according to claim 14, characterized in that Also includes: multiple energy storage devices; The energy storage device is connected to the second port of the first single-phase converter device and the second port of the second single-phase converter device; Wherein, the energy storage device is configured to store the residual power of one or more traction substations among multiple traction substations; the residual power includes one or more of residual ride-through power and residual regenerative power; the energy storage device is also configured to supply power to the corresponding traction substation through the second single-phase converter.

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