Control method of power distribution system and power distribution system

Abstract

The present invention discloses a control method for a power distribution system and a power distribution system, which include the following steps: S1: a busbar with an abnormal power supply is used as a power-off busbar, and a busbar with a normal power supply is used as a normal busbar, and a first energy storage module connected to the power-off busbar is connected to the normal busbar; S2: when a second energy storage module connected to the normal busbar is in a discharging state, it is judged whether the load power of the normal busbar meets the supplementary energy storage discharge condition; if so, the first energy storage module discharges to the normal busbar; if not, the first energy storage module enters a standby state; S3: when the second energy storage module is in a charging state, it is judged whether the load power of the normal busbar meets the supplementary energy storage charging condition; if so, the first energy storage module is charged through the normal busbar; if not, the first energy storage module enters a standby state.

Description

Technical Field

[0001] The present invention relates to the field of power distribution technology, and in particular to a control method for a power distribution system and a power distribution system. Background Art

[0002] As an important part of the power grid, the distribution system is directly connected to the user end, and its operating status is directly related to the reliability of power supply. The existing distribution system usually has two bus sections, which are powered by two power supplies respectively. The two bus sections are independent of each other and serve as complementary power supplies to each other. The energy storage modules connected to each bus section operate independently and only adjust the power for their respective buses to avoid problems such as reverse current, overcurrent or tripping of the bus. When the power supply of a bus section is abnormal, the bus section is in a power-off state, and the power supply of the other bus section supplies power to the load equipment of the power-off bus. The energy storage module connected to the power-off bus cannot sample the load power of the normal bus and cannot adjust the power of the normal bus, so the energy storage module connected to the power-off bus cannot operate, which results in low utilization of the energy storage module in the existing distribution system when a power failure occurs in a bus section, and poor continuous stability of the distribution system operation. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a control method and a distribution system for a power distribution system, so as to solve the problem of poor continuous stability of the existing power distribution system when the power supply of a bus is abnormal.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: to provide a control method of a power distribution system, which is applied to a power distribution system with two busbars, and comprises the following steps:

[0005] S1: The busbar with abnormal power supply is used as the power-off busbar, the busbar with normal power supply is used as the normal busbar, and the first energy storage module connected to the power-off busbar is connected to the normal busbar;

[0006] S2: When the second energy storage module connected to the normal bus is in a discharging state, determine whether the load power of the normal bus meets the supplementary energy storage discharge condition; if so, the first energy storage module discharges to the normal bus; if not, the first energy storage module enters a standby state;

[0007] S3: When the second energy storage module is in a charging state, determine whether the load power of the normal bus meets the supplementary energy storage charging conditions; if so, the first energy storage module is charged through the normal bus; if not, the first energy storage module enters a standby state.

[0008] Further, judging whether the load power of the normal bus meets the supplementary energy storage discharge condition specifically includes the following steps:

[0009] S201: Determine whether the normal bus has reverse active power; if so, the first energy storage module enters a standby state; if not, execute step S202;

[0010] S202: Determine whether the discharge power of the second energy storage module meets the load operation requirement of the normal bus; if so, the first energy storage module enters a standby state; if not, the first energy storage module discharges to the normal bus.

[0011] Furthermore, the load operation requirement of the normal bus in step S202 includes: a ratio of the discharge power of the second energy storage module to the load demand power of the normal bus is greater than a first preset percentage.

[0012] Furthermore, the step S201 also includes: when reverse active power appears in the normal bus, reducing the discharge power of the second energy storage module.

[0013] Furthermore, in step S2, the first energy storage module discharges to the normal bus, including: obtaining the difference between the load demand power of the normal bus and the discharge power of the second energy storage module, and adjusting the discharge power of the first energy storage module to a second preset percentage of the difference.

[0014] Furthermore, in step S3, judging whether the load power of the normal bus satisfies the supplementary energy storage charging condition includes: judging whether the load power of the normal bus reaches a preset power protection value; if so, the first energy storage module is charged through the normal bus; if not, the first energy storage module enters a standby state.

[0015] Furthermore, in step S3, the first energy storage module is charged through the normal bus, including: obtaining the remaining available power of the normal bus, and adjusting the charging power of the first energy storage module to a third preset percentage of the remaining available power.

[0016] Furthermore, the de-energized busbars are connected to each other via a communication cabinet, and the communication cabinet includes a first switch for controlling the connection or disconnection of the de-energized busbars with the normal busbars; in the step S1, the first energy storage module connected to the de-energized busbar is connected to the normal busbar, including: the first switch is changed from an open state to a closed state to connect the first energy storage module to the normal busbar.

[0017] Another object of the present invention is to provide a power distribution system, which is controlled by the above-mentioned control method, including two power distribution units and a connecting cabinet, the two power distribution units each including a bus, an energy storage module, an incoming line cabinet and a converter, the energy storage module and the incoming line cabinet are both connected to the bus, the converter is connected to the incoming line cabinet, the incoming line cabinet includes a collection module for obtaining the load power of the bus, the collection module is communicatively connected to the energy storage module, and the energy storage modules of the two power distribution units are communicatively connected; the busbars of the two power distribution units are connected through a connecting cabinet, and the connecting cabinet includes a first switch.

[0018] Furthermore, a second switch is provided between the converter and the incoming line cabinet.

[0019] The beneficial effects of the present invention are as follows: in the case where the power supply of a section of bus is in an abnormal state, the control method of the power distribution system provided by the present invention uses the section of bus as a power-off bus, and uses the first energy storage module connected to the power-off bus as a supplementary energy storage module for the normal bus. In the control method provided by the present invention, the first energy storage module can be discharged or charged through the normal bus to ensure that the normal bus can meet the power requirements of all loads, thereby improving the utilization rate of the overall energy storage modules of the power distribution system when the power supply of a section of bus is in an abnormal state, thereby improving the reliability, stability and sustainability of the power distribution system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 A flow chart of a control method provided by the present invention in one embodiment;

[0021] Figure 2 A schematic diagram of a power distribution system provided by the present invention in one embodiment.

[0022] Description of labels:

[0023] 1. Power distribution unit; 2. Contact cabinet; 3. Busbar; 4. Energy storage module; 5. Incoming cabinet; 6. Converter; 7. First switch; 8. Second switch; 9. Collection module. DETAILED DESCRIPTION

[0024] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in combination with the implementation modes and the accompanying drawings.

[0025] Please refer to Figure 1 as well as Figure 2 The control method of the power distribution system is applied to a power distribution system with two busbars, and comprises the following steps:

[0026] S1: The busbar with abnormal power supply is used as the power-off busbar, the busbar with normal power supply is used as the normal busbar, and the first energy storage module connected to the power-off busbar is connected to the normal busbar;

[0027] S2: When the second energy storage module connected to the normal bus is in a discharging state, determine whether the load power of the normal bus meets the supplementary energy storage discharge condition; if so, the first energy storage module discharges to the normal bus; if not, the first energy storage module enters a standby state;

[0028] S3: When the second energy storage module is in a charging state, determine whether the load power of the normal bus meets the supplementary energy storage charging conditions; if so, the first energy storage module is charged through the normal bus; if not, the first energy storage module enters a standby state.

[0029] The working principle of the present invention is briefly described as follows: the control method provided by the present invention can be applied to a power distribution system with two bus sections. When the power supply of one bus section in the power distribution system is in an abnormal state and the power supply of the other bus section is in a normal state, the first energy storage module connected to the power-off bus is connected to the normal bus, so that the first energy storage module can be used as a supplementary energy storage module for the normal bus. When the discharge power of the second energy storage module cannot meet the power requirements of all loads powered by the normal bus, the first energy storage module discharges to the second bus to ensure that the normal bus can meet the power requirements of all loads; when the second energy storage module is charged and the load power of the normal bus can meet the energy storage charging conditions, the first energy storage module is charged through the normal bus to increase the duration of stable operation of the power distribution system when the power supply of one bus section is in an abnormal state.

[0030] As can be seen from the above description, the beneficial effects of the present invention are as follows: in the case where the power supply of a section of the bus is in an abnormal state, the control method of the power distribution system provided by the present invention uses the first energy storage module connected to the de-energized bus as a supplementary energy storage module for the normal bus; wherein, when the discharge power of the second energy storage module cannot meet the power requirements of all loads on the normal bus, the first energy storage module can discharge to the normal bus to ensure that the normal bus can meet the power requirements of all loads; the first energy storage module is charged through the normal bus, and the utilization rate of the overall energy storage module of the power distribution system is improved when the power supply of a section of the bus is in an abnormal state, thereby improving the reliability, stability and sustainability of the power distribution system.

[0031] Further, judging whether the load power of the normal bus meets the supplementary energy storage discharge condition specifically includes the following steps:

[0032] S201: Determine whether the normal bus has reverse active power; if so, the first energy storage module enters a standby state; if not, execute step S202;

[0033] S202: Determine whether the discharge power of the second energy storage module meets the load operation requirement of the normal bus; if so, the first energy storage module enters a standby state; if not, the first energy storage module discharges to the normal bus.

[0034] From the above description, it can be seen that when there is no reverse active power on the normal bus and the discharge power of the second energy storage system cannot meet the power requirements of all loads on the normal bus, the first energy storage module discharges to the normal bus so that the normal bus can meet the power requirements of all loads.

[0035] Furthermore, the load operation requirement of the normal bus in step S202 includes: a ratio of the discharge power of the second energy storage module to the load demand power of the normal bus is greater than a first preset percentage.

[0036] From the above description, it can be seen that the load demand power of the normal bus refers to the sum of the demand powers of all loads powered by the normal bus. When the discharge power of the second energy storage module cannot meet the load demand power of the normal bus, the power supply reliability and stability of the normal bus to all loads powered by it are reduced. At this time, the first energy storage module discharges to the normal bus so that the discharge power of the first energy storage module supplements the load power of the normal bus, thereby improving the reliability and stability of the normal bus power supply to the load.

[0037] Furthermore, the step S201 also includes: when reverse active power appears in the normal bus, reducing the discharge power of the second energy storage module.

[0038] It can be seen from the above description that when reverse active power appears in the normal bus, the discharge power of the second energy storage module is reduced to prevent the discharge power of the second energy storage module from being too large and causing the normal bus to supply reverse power to its power supply.

[0039] Furthermore, in step S2, the first energy storage module discharges to the normal bus, including: obtaining the difference between the load demand power of the normal bus and the discharge power of the second energy storage module, and adjusting the discharge power of the first energy storage module to a second preset percentage of the difference.

[0040] From the above description, it can be seen that the difference between the load demand power of the normal bus and the discharge power of the second energy storage module is the remaining demand power of the normal bus. The first energy storage module discharges to the normal bus according to a second preset percentage of the remaining discharge power to prevent a sudden decrease in the load of the normal bus and the occurrence of reverse flow.

[0041] Furthermore, in step S3, judging whether the load power of the normal bus satisfies the supplementary energy storage charging condition includes: judging whether the load power of the normal bus reaches a preset power protection value; if so, the first energy storage module is charged through the normal bus; if not, the first energy storage module enters a standby state.

[0042] It can be seen from the above description that in actual application, the preset power protection value can be set according to the power protection value of the converter connected to the normal bus. When the load power of the normal bus is less than the preset power protection value, the first energy storage module can be charged using the remaining available power of the normal bus to improve the sustainability of the first energy storage module and improve the reliability, stability and sustainability of the distribution system.

[0043] Furthermore, in step S3, the first energy storage module is charged through the normal bus, including: obtaining the remaining available power of the normal bus, and adjusting the charging power of the first energy storage module to a third preset percentage of the remaining available power.

[0044] It can be seen from the above description that the remaining available power is the difference between the maximum operating power of the normal bus and its load power. The control method controls the first energy storage module to charge using the third preset percentage of the remaining available power of the normal bus to avoid the load power of the normal bus exceeding the capacity of the converter connected to the normal bus when the normal bus charges the first energy storage module. The control method has high reliability and stability.

[0045] Furthermore, the de-energized busbars are connected to each other via a communication cabinet, and the communication cabinet includes a first switch for controlling the connection or disconnection of the de-energized busbars with the normal busbars; in the step S1, the first energy storage module connected to the de-energized busbar is connected to the normal busbar, including: the first switch is changed from an open state to a closed state to connect the first energy storage module to the normal busbar.

[0046] It can be seen from the above description that whether the first energy storage module can be connected to the normal bus can be determined by identifying the open or closed state of the first switch.

[0047] Another object of the present invention is to provide a power distribution system, which is controlled by the above-mentioned control method, including two power distribution units 1 and a connecting cabinet 2, the two power distribution units 1 each including a bus 3, an energy storage module 4, an incoming line cabinet 5 and a converter 6, the energy storage module 4 and the incoming line cabinet 5 are both connected to the bus 3, the converter 6 is connected to the incoming line cabinet 5, the incoming line cabinet 5 includes a collection module 9 for obtaining the load power of the bus 3, the collection module 9 is communicatively connected to the energy storage module 4, and the energy storage modules 4 of the two power distribution units 1 are communicatively connected; the bus bars 3 of the two power distribution units 1 are connected through the connecting cabinet 2, and the connecting cabinet 2 includes a first switch 7.

[0048] From the above description, it can be seen that the two distribution units of the distribution system serve as each other's supplementary distribution units. The two distribution units can be connected through a connecting cabinet. When the power supply of the busbar of one distribution unit is in an abnormal state and the power supply of the busbar of the other distribution unit is normal, the energy storage module of the distribution unit where the power-off busbar is located can realize the power regulation function of the normal busbar, so as to improve the reliability, stability and sustainability of the distribution system.

[0049] Furthermore, a second switch 8 is provided between the converter 6 and the incoming line cabinet 5 .

[0050] It can be seen from the above description that when the power supply of the busbar of one of the distribution units is in an abnormal state, the second switch can be changed from a closed state to an open state. In actual application, the battery management system of the energy storage module of the distribution unit can determine whether to serve as a supplementary energy storage module of the energy storage module of another distribution unit according to the states of the first switch and the second switch.

[0051] Example

[0052] Please refer to Figure 1 to Figure 2 The embodiment of the present invention is to provide a control method for a power distribution system, which can be applied to control the following power distribution system: Figure 2 As shown, the power distribution system includes two power distribution units 1 and a connecting cabinet 2. The two power distribution units 1 both include a bus 3, an energy storage module 4, an incoming line cabinet 5 and a converter 6. The energy storage module 4 and the incoming line cabinet 5 are both connected to the bus 3. The input ends of the converters 6 of the two power distribution units 1 are respectively connected to two power supplies, which may be a power distribution network. The output end of the converter 6 is connected to the incoming line cabinet 5, and a second switch 8 is provided between the converter 6 and the incoming line cabinet 5; the converter 6 is connected to the incoming line cabinet 5, and the incoming line cabinet 5 includes a collection module 9 for obtaining the load power of the bus 3. The collection module 9 is communicatively connected to the energy storage module 4, and the energy storage modules 4 of the two power distribution units 1 are communicatively connected; the bus 3 of the two power distribution units 1 are connected through the connecting cabinet 2, and the connecting cabinet 2 includes a first switch 7.

[0053] In the power distribution system, when the power supply of the busbar of the distribution unit is in an abnormal state, the second switch of the distribution unit will be switched from an open state to a closed state to disconnect the busbar from the power supply. The battery management system of the energy storage module can determine whether the power supply of the distribution unit in which it is located is in an abnormal state by monitoring the state of the second switch.

[0054] In a power distribution system, when the power supply of a busbar of one power distribution unit is in an abnormal state and the power supply of a busbar of another power distribution system is in a normal state, the power distribution system can be controlled by using the control method provided in this embodiment, including the following steps:

[0055] S1: The busbar with abnormal power supply is used as the power-off busbar, and the busbar with normal power supply is used as the normal busbar, and the first energy storage module connected to the power-off busbar is connected to the normal busbar.

[0056] In detail, in the power distribution system provided in the present embodiment, when the power supply of the busbar of one distribution unit is in an abnormal state and the power supply of the busbar of another distribution unit is in a normal state, the busbar 3 with the power supply in the abnormal state cannot supply power to its load, and therefore the busbar 3 with the power supply in the abnormal state is used as a power-off busbar, and the energy storage module 4 of the distribution unit 1 where the power-off busbar is located is used as the first energy storage module; the busbar 3 with the power supply in the normal state is used as a normal busbar, and the energy storage module 4 of the distribution unit 1 where the normal busbar is located is used as the second energy storage module.

[0057] When the power supply of the busbar of one distribution unit 1 in the power distribution system is in an abnormal state and the power supply of the busbar of another distribution unit 1 is in a normal state, the operation and maintenance personnel may select the switch state of the first switch 7:

[0058] 1. When the load of the power-off bus needs to be powered by the power supply of the normal bus, the first switch 7 can be controlled to close. At this time, the power supply of the normal bus supplies power to the load of the power-off bus and the load of the normal bus at the same time. The first energy storage module is electrically connected to the normal bus through the closed first switch 7. The first energy storage module can be used as a supplementary energy storage module for the normal bus. The first energy storage module is connected in communication with the second energy storage module to obtain operating parameter information such as the load power of the normal bus and the discharge power or charging power of the second energy storage module;

[0059] 2. When the power supply of the de-energized bus needs to be repaired, the operation and maintenance personnel can control the first switch 7 and the second switch 8 to be in the open state. At this time, the distribution unit 1 where the de-energized bus is located is in the whole de-energized state, reducing the auxiliary power loss.

[0060] In this embodiment, the first energy storage module can determine whether to serve as a supplementary energy storage module for the normal bus according to the state of the first switch 7 and the state of the second switch 8 of the distribution unit 1 in which it is located: when the first switch 7 is in a closed state and the second switch 8 is in an open state, the first energy storage module serves as a supplementary energy storage module for the normal bus; when both the first switch 7 and the second switch 8 are in an open state, the first energy storage module enters a power-off state to reduce the auxiliary source power loss; when the first switch 7 is in an open state and the second switch 8 is in a closed state, the first energy storage module can communicate with the acquisition module 9 to obtain the load power state of the power-off bus to determine whether the power supply of the power-off bus has recovered to a normal state.

[0061] The control method provided in this embodiment also includes step S2: when the second energy storage module connected to the normal bus is in a discharging state, determining whether the load power of the normal bus meets the supplementary energy storage discharge condition; if so, the first energy storage module discharges to the normal bus; if not, the first energy storage module enters a standby state.

[0062] Specifically, judging whether the load power of the normal bus meets the supplementary energy storage discharge condition includes the following steps:

[0063] S201: Determine whether the normal bus has reverse active power; if so, the first energy storage module enters a standby state; if not, execute step S202;

[0064] S202: Determine whether the discharge power of the second energy storage module meets the load operation requirement of the normal bus; if so, reduce the discharge power of the second energy storage module, and the first energy storage module enters a standby state; if not, the first energy storage module discharges to the normal bus;

[0065] The load operation requirement of the normal bus in step S202 includes: the ratio of the discharge power of the second energy storage module to the load demand power of the normal bus is greater than a first preset percentage. In this embodiment, the first preset percentage can be set to 80%.

[0066] In this embodiment, when the second energy storage module is in a discharging state, if the load power of the normal bus does not have reverse active power, and the discharge power of the second energy storage module fails to meet the power requirements of all loads of the normal bus, the first energy storage module discharges to the normal bus to supplement the load power of the normal bus with the discharge power of the first energy storage module.

[0067] In order to prevent the reverse flow caused by the large change in load power of the normal bus, in step S202, the first energy storage module discharges to the normal bus, including: obtaining the difference between the load demand power of the normal bus and the discharge power of the second energy storage module, and adjusting the discharge power of the first energy storage module to a second preset percentage of the difference. In this embodiment, the second preset percentage can be set to 90%.

[0068] For ease of understanding, the above steps are illustrated as follows: the sum of the power requirements of all loads on the normal bus is 800kW, and the discharge power of the second energy storage module is 500kW. The ratio of the discharge power of the second energy storage module to the load demand power of the normal bus is 55.56%, which is less than 80% of the first preset percentage. The normal bus still has a remaining demand power of 300kW. The discharge power of the first energy storage module to the normal bus is adjusted to 90% of the second preset percentage of the remaining demand power of 300kW, that is, the first energy storage module discharges to the normal bus at a discharge power of 270kW, which can supplement the load power of the normal bus, ensure that the load power of the normal bus can meet the power requirements of all loads, and prevent the normal bus from having a reverse flow due to its large load power change. When the sum of the power requirements of all loads on the normal bus is 800kW, and the discharge power of the second energy storage module is greater than 640kW, that is, when the ratio of the discharge power of the second energy storage module to the load power requirement of the normal bus is greater than 80% of the first preset percentage, it is determined that the discharge power of the second energy storage module meets the requirements of all loads on the normal bus, and the first energy storage module enters the standby state.

[0069] The control method provided in this embodiment also includes step S3: when the second energy storage module is in a charging state, determining whether the load power of the normal bus meets the supplementary energy storage charging condition; if so, the first energy storage module is charged through the normal bus; if not, the first energy storage module enters a standby state.

[0070] In this embodiment, in step S3, judging whether the load power of the normal bus satisfies the supplementary energy storage charging condition includes: judging whether the load power of the normal bus reaches a preset power protection value; if so, the first energy storage module is charged through the normal bus; if not, the first energy storage module enters a standby state.

[0071] In this embodiment, in step S3, the first energy storage module is charged through the normal bus, including: obtaining the remaining available power of the normal bus, and adjusting the charging power of the first energy storage module to a third preset percentage of the remaining available power. In this embodiment, the third preset percentage is 90%.

[0072] When the second energy storage module is in a charging state, the preset power protection value of the normal bus can be collected; for example, 80% of the power protection value of the converter connected to the normal bus can be used as the preset power protection value of the normal bus to prevent the normal bus from causing overcurrent and tripping of the converter during operation.

[0073] Among them, when the second energy storage module is in a charging state and the load power of the normal bus does not reach the preset power protection value, the first energy storage module can use the remaining available power of the normal bus for charging to improve the reliability and stability of the first energy storage module.

[0074] For ease of understanding, the above steps are illustrated as follows: when the power protection value of the converter connected to the normal power is 1000kW, the preset power protection value of the normal bus is set to 80% of the power protection value of the converter, that is, the preset power protection value is 800kW. If the load power of the normal bus is 500kW at this time, the load power of the normal bus is less than the preset power protection value, and the remaining usable power of the normal bus is 500kW, the charging power of the first energy storage module charged through the normal bus is adjusted to the third preset percentage of 90% of the remaining usable power of 500kW, that is, the first energy storage module is charged through the normal bus at a charging power of 450kW. When the preset power protection value of the normal bus is 800kW, and the load power of the normal bus reaches 800kW, that is, the ratio of the load power of the normal bus reaches the preset power protection value, it is judged that the normal bus cannot meet the supplementary energy storage charging conditions, and the first energy storage module enters the standby state.

[0075] In the power distribution system provided in this embodiment, when the power supplies of the busbars of the two distribution units 1 are in a normal state, the second switches 8 of the two distribution units 1 are in a closed state; in the distribution units 1, the power supply can electrically conduct the busbar 3 and supply power to the busbar 3; the first switch 7 of the connecting cabinet 2 remains in an open state so that the two distribution units 1 can work independently of each other.

[0076] When the distribution unit 1 operates independently, a collection module 9 is provided on the incoming cabinet 5 of the distribution unit 1, and the collection module 9 can collect the load power of the bus 3. The energy storage module 4 is communicated with the collection module 9 to perform power limiting control or backflow prevention control on the bus 3 according to the load power of the bus 3 collected by the collection module 9.

[0077] In detail, during the charging process of the energy storage module 4, the energy storage module 4 can be regarded as a load device powered by the bus 3. The collection module 9 collects the forward active power of the incoming cabinet 5 to determine whether the load power of the bus 3 exceeds the power protection value of the converter 6. If the load power of the bus 3 exceeds the power protection value of the converter 6, the charging power of the energy storage module 4 is reduced to prevent the energy storage module 4 from causing the converter 6 to overcurrent and trip during the charging process; if the load power of the bus 3 does not exceed the power protection value of the converter 6, the energy storage module 4 is charged according to the rated charging power.

[0078] During the discharge of the energy storage module 4, the acquisition module 9 acquires the reverse active power of the incoming cabinet 5 to determine whether the bus 3 has reverse active power and reverse power transmission, that is, when the reverse active power of the bus 3 is greater than 0kW, the discharge power of the energy storage system is reduced to avoid the bus 3 supplying reverse power to its power supply; if the bus 3 does not have reverse active power, the energy storage module 4 discharges according to its rated discharge power.

[0079] When the power supplies of the buses of the two distribution units 1 are normal, the energy storage module 4 obtains the load power of the bus 3 according to the acquisition module 9 of the distribution unit 1 in which it is located, and only performs backflow prevention control or power limiting control on the bus 3 to which it is connected.

[0080] When the power supply of the bus 3 of one distribution unit 1 is in an abnormal state and the power supply of the bus 3 of another distribution unit 1 is in a normal state, when the first switch 7 is in a closed state, the energy storage module 4 connected to the de-energized bus establishes communication with the energy storage module 4 connected to the normal bus, so that the energy storage module 4 connected to the de-energized bus can obtain the load power of the normal bus, and serve as a supplementary energy storage module of the normal bus to perform power regulation on the normal bus.

[0081] In summary, the control method of the power distribution system provided by the present invention uses the first energy storage module connected to the de-energized bus as a supplementary energy storage module for the normal bus when the power supply of a section of the bus is in an abnormal state; wherein, when the discharge power of the second energy storage module cannot meet the power requirements of all loads on the normal bus, the first energy storage module can discharge to the normal bus to ensure that the normal bus can meet the power requirements of all loads; the first energy storage module is charged by the normal bus, and the utilization rate of the overall energy storage modules of the power distribution system is improved when the power supply of a section of the bus is in an abnormal state, thereby improving the reliability, stability and sustainability of the power distribution system.

[0082] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A control method for a power distribution system, applied to a power distribution system with two busbars, characterized in that: The following steps are involved: S1: The busbar with abnormal power supply is used as the power-off busbar, the busbar with normal power supply is used as the normal busbar, and the first energy storage module connected to the power-off busbar is connected to the normal busbar; S2: When the second energy storage module connected to the normal bus is in a discharging state, determine whether the load power of the normal bus meets the supplementary energy storage discharge condition; if so, the first energy storage module discharges to the normal bus; if not, the first energy storage module enters a standby state; S3: When the second energy storage module is in a charging state, determine whether the load power of the normal bus meets the supplementary energy storage charging condition; if so, the first energy storage module is charged through the normal bus; if not, the first energy storage module enters a standby state; In the step S2, the first energy storage module discharges to the normal bus, including: obtaining the difference between the load demand power of the normal bus and the discharge power of the second energy storage module, and adjusting the discharge power of the first energy storage module to a second preset percentage of the difference; Determining whether the load power of the normal bus meets the supplementary energy storage discharge condition specifically includes the following steps: S201: Determine whether the normal bus has reverse active power; if so, the first energy storage module enters a standby state; if not, execute step S202; S202: Determine whether the discharge power of the second energy storage module meets the load operation requirement of the normal bus; if so, the first energy storage module enters a standby state; if not, the first energy storage module discharges to the normal bus.

2. The control method according to claim 1, characterized in that: The load operation requirement of the normal bus in step S202 includes: a ratio of the discharge power of the second energy storage module to the load demand power of the normal bus is greater than a first preset percentage.

3. The control method according to claim 1, characterized in that: The step S201 further includes: when reverse active power appears on the normal bus, reducing the discharge power of the second energy storage module.

4. The control method according to claim 1, characterized in that: In the step S3, it is determined whether the load power of the normal bus meets the supplementary energy storage charging condition, including: determining whether the load power of the normal bus reaches a preset power protection value; if so, the first energy storage module is charged through the normal bus; if not, the first energy storage module enters a standby state.

5. The control method according to claim 1, characterized in that: In the step S3, the first energy storage module is charged through the normal bus, including: obtaining the remaining available power of the normal bus, and adjusting the charging power of the first energy storage module to a third preset percentage of the remaining available power.

6. The control method according to claim 1, characterized in that: The de-energized busbars are connected to each other via a connecting cabinet, and the connecting cabinet includes a first switch for controlling the connection or disconnection of the de-energized busbar with the normal busbar; in the step S1, the first energy storage module connected to the de-energized busbar is connected to the normal busbar, including: the first switch is changed from an open state to a closed state to connect the first energy storage module to the normal busbar.

7. A power distribution system, characterized in that, It is controlled by the control method described in any one of claims 1 to 6, and includes two distribution units and a connecting cabinet. The two distribution units each include a bus, an energy storage module, an incoming line cabinet and a converter. The energy storage module and the incoming line cabinet are both connected to the bus, the converter is connected to the incoming line cabinet, the incoming line cabinet includes a collection module for obtaining the load power of the bus, the collection module is communicatively connected to the energy storage module, and the energy storage modules of the two distribution units are communicatively connected; the busbars of the two distribution units are connected through a connecting cabinet, and the connecting cabinet includes a first switch.

8. The power distribution system according to claim 7, characterized in that: A second switch is provided between the converter and the incoming line cabinet.

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