阅读说明：本技术 一种基于5g网络通信的配电网保护及自愈系统 (Power distribution network protection and self-healing system based on 5G network communication ) 是由 蔡玉朋 王同 张武洋 卢盛阳 史松杰 王英明 王鹤奇 黄未 楚天丰 董明 于 2021-06-25 设计创作，主要内容包括：本发明属于配电网技术领域,尤其涉及一种基于5G网络通信的配电网保护及自愈系统,具体是一种适用于配电网环网线路的基于5G网络通信的配电网保护及自愈系统。本发明包括差动保护终端和分段备自投终端构成。本发明提供一种智能配电一体化终端为基础,终端之间可通过5G网络通信的系统,同时各终端间信息的实时共享交互,备自投逻辑简单,延时较短。解决了配电网保护级差配合困难,传统差动保护依赖专用光纤通道、光纤通讯工程实施成本高、周期长等难题。可实现配电网故障的精准定位和供电能力的快速自愈,适用于多级配网或者地铁大分区环网供电线路转供电。(The invention belongs to the technical field of power distribution networks, particularly relates to a power distribution network protection and self-healing system based on 5G network communication, and particularly relates to a power distribution network protection and self-healing system based on 5G network communication and suitable for a looped network line of a power distribution network. The invention comprises a differential protection terminal and a sectional spare power automatic switching terminal. The invention provides a system based on intelligent power distribution integrated terminals, which can communicate through a 5G network between the terminals, simultaneously shares and interacts information among the terminals in real time, and has simple spare power automatic switching logic and shorter time delay. The problems that the protection level difference of the power distribution network is difficult to match, the traditional differential protection depends on a special optical fiber channel, the implementation cost of the optical fiber communication engineering is high, the period is long and the like are solved. The method can realize accurate positioning of the power distribution network fault and quick self-healing of the power supply capacity, and is suitable for power supply transfer of a multi-stage power distribution network or a subway large-partition ring network power supply line.)

1. The utility model provides a distribution network protection and self-healing system based on 5G network communication, characterized by: the system comprises a protection terminal and a sectional spare power automatic switching terminal.

2. The power distribution network protection and self-healing system based on 5G network communication according to claim 1, characterized in that: the protection terminal is a differential protection terminal.

3. The power distribution network protection and self-healing system based on 5G network communication according to claim 1, characterized in that: the protection terminal comprises a first terminal (11), a second terminal (12), a third terminal (13), a fourth terminal (14), a fifth terminal (21), a sixth terminal (22), a seventh terminal (23) and an eighth terminal (24), wherein line differential protection is respectively formed by the first terminal (11) and the second terminal (12) of looped network incoming lines of the looped network unit, and the fifth terminal (21) and the sixth terminal (22) of the looped network unit, and the two terminals are respectively in communication connection through a 5G network;

the second terminal (12) and the sixth terminal (22) respectively form a tie line differential protection with a terminal A (112) and a terminal B (122) of an adjacent ring network unit, and the two terminals are communicated through a 5G network;

the spare power automatic switching terminal (10), the second terminal (12), the third terminal (13) and the fourth terminal (14) respectively form bus protection, and the four terminals are respectively interconnected through optical fibers;

the spare power automatic switching terminal (10), the sixth terminal (22), the seventh terminal (23) and the eighth terminal (24) respectively form bus protection, and the four terminals are respectively interconnected through optical fibers.

4. The power distribution network protection and self-healing system based on 5G network communication according to claim 3, characterized in that: when a looped network cable of the looped network unit fails, a fault protection terminal of the looped network unit trips off a corresponding breaker to perform fault isolation, and sends a starting standby switching signal; after the spare automatic switching terminal receives a starting spare switching signal sent by a fault protection terminal of the ring network unit, the spare automatic switching terminal confirms that the fault bus has no power supply voltage, the fault is isolated, the power supply voltage of the bus to be switched is normal, and after the spare switching device is charged, the action of a switching circuit breaker of the ring network unit is controlled after a set time period is delayed, and the bus switching power supply is completed.

5. The power distribution network protection and self-healing system based on 5G network communication according to claim 1, characterized in that: the protection terminal is configured with an address-based network route, the CPE is accessed to the 5G network, and the CPE route is deployed in a sinking core network near the base station, so that the intercommunication of the DTU network is realized.

6. The power distribution network protection and self-healing system based on 5G network communication according to claim 3, characterized in that: the ring network unit inlet and outlet lines are all provided with differential protection terminals, and when the distribution network main line fails, the differential protection terminals act to rapidly remove the failure at the outlet; the interval protection terminal exchanges a phase overcurrent starting state, a zero sequence overcurrent starting state, a single-phase grounding line selection starting state, a phase overcurrent positive direction state, a zero sequence overcurrent positive direction state and a grounding line selection positive direction state with an adjacent interval protection terminal through a 5G-based wireless communication network to carry out looped network fault judgment, switch station bus fault judgment and feed-out line fault judgment.

7. The power distribution network protection and self-healing system based on 5G network communication according to claim 6, wherein: the looped network fault judgment comprises the following steps:

1) the circuit is an incoming and outgoing line;

2) starting at least one of two sides at intervals;

2) all the starting intervals on both sides are not in the opposite direction of the fault.

8. The power distribution network protection and self-healing system based on 5G network communication according to claim 6, wherein: the bus fault judgment of the switching station comprises the following steps:

1) at least one interval is started;

2) all the start intervals are not positive fault directions.

9. The power distribution network protection and self-healing system based on 5G network communication according to claim 3, characterized in that: when a looped network cable of the looped network unit fails, a fault protection terminal of the looped network unit trips to a breaker at a protection installation position for fault isolation, and sends a starting standby switching signal to a next-stage sectional standby automatic switching terminal; when a bus of a ring network unit fails, an incoming line fault protection terminal of a fault bus trips an incoming line breaker of the fault bus in parallel to perform fault isolation with an outgoing line breaker of a bus, and simultaneously trips an incoming line breaker of a next ring network unit, and the incoming line breaker of the next ring network unit sends a standby switching starting signal to a sectional standby automatic switching terminal of the stage; after the sectional spare power automatic switching terminal receives a starting spare switching signal sent by a fault protection terminal of the ring network unit, the incoming line is confirmed to be tripped, the fault bus has no power supply voltage, the power supply voltage of the bus to be switched is normal, and the standby switching equipment is charged completely, the combined sectional breaker of the ring network unit is controlled to act after a time delay set time period, and the bus is switched to supply power.

10. The power distribution network protection and self-healing system based on 5G network communication according to claim 3, characterized in that: when a looped network cable of the looped network unit has a fault, the next-stage incoming line tripping signal starts the fast spare power automatic switching device, and selective power distribution network protection such as differential protection and dynamic self-adaptive protection T1 section action signals configured on the incoming line are transmitted to the local subsection spare power automatic switching device in a hard-open or GOOSE mode;

in the second looped network unit, after the local backup power automatic switching charging is completed, when the circuit where the breaker of the I mother terminal A (112) is located starts the backup power switching action, the non-voltage of the I mother three-wire is judged, any one wire of the II mother is judged to have the voltage, and after the breaker of the terminal A (112) is confirmed to be tripped, the circuit is switched on and off through 'section switching-on delay'; when a circuit where a breaker of a first female terminal B (122) is located starts a standby switch-in action, judging whether three lines of a second female are pressureless and any line of the first female has pressure, and switching on a segmented breaker through 'segmented switching-on delay' after the breaker of the terminal B (122) is confirmed to be tripped;

the local spare power automatic switching function is configured at the bus-bar joint of each ring network unit, and the local bus-bar joint spare power automatic switching is started by the last cascade jump incoming line;

when a looped network cable has a fault, the fault occurs at a point A between a first terminal (11) breaker and a second terminal (12) breaker, the fault location is realized by the dynamic adaptive protection of the first terminal (11) breaker, the first terminal (11) breaker is tripped, the second terminal (12) breaker is tripped in parallel, the fault isolation is realized, the third looped network unit is started to carry out on-site spare power automatic switching, the second terminal (12) breaker is tripped, the left side bus is subjected to voltage loss, the right side bus is subjected to voltage reduction, and the left side bus of the third looped network unit is switched to supply power;

when a bus fails, the fault occurs at a bus D point where a breaker of a first terminal (11) of a first ring network unit is located, fault location is achieved by a dynamic adaptive protection device configured at the breaker of a third terminal (13) to trip off the breaker of the third terminal (13), a breaker of the first terminal (11) is tripped in a connected mode, a breaker of a second terminal (12) is tripped in a connected mode, fault isolation is achieved, the third ring network unit is started to be in a standby power automatic switching mode on site, it is confirmed that the breaker of the second terminal (12) is tripped, the left side bus is in a voltage loss state, the right side bus is in a voltage state, and power supply switching of the left side bus of the third ring network unit is achieved.

Technical Field

The invention belongs to the technical field of power distribution networks, particularly relates to a power distribution network protection and self-healing system based on 5G network communication, and particularly relates to a power distribution network protection and self-healing system based on 5G network communication and suitable for a looped network line of a power distribution network.

Background

The power distribution network directly faces to users, is an important link in power supply, and the safety and the reliability of the power distribution network play a vital role in the development of national economy. The current intelligent power grid power distribution and utilization service terminals are multi-faceted, wide and distributed, the optical fiber communication mode has the advantage of strong service transmission capability, but the deployment and construction difficulty is high, the cost is high, the full coverage of massive power distribution and utilization terminals cannot be met, meanwhile, the short medium-low voltage short circuit in the power distribution network is still protected by traditional current or distance, the short medium-low voltage short circuit is difficult to match with the power distribution network in the setting value and the action time, and the phenomenon that the accident range of the power distribution network is expanded frequently occurs.

At present, a core area with high requirement on power supply reliability of a domestic power distribution network adopts a 3-5 segmented double-loop network power supply mode to introduce 2 paths of power supplies from a transformer substation, the field of urban rail transit is particularly prominent, a large number of large-partition power supplies are used in a subway power supply system at present, and a looped network unit/a switch station/a subway traction substation are connected in a single bus segment mode. The traditional operation topological mode has the problems that differential protection depends on a special optical fiber channel, the implementation cost of optical fiber communication engineering is high, the period is long, and the like, and simultaneously has the problems that information between terminals cannot be shared and interacted in real time, the fault of a power distribution network is not accurate enough, and the power supply capacity is not perfect enough.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a power distribution network protection and self-healing system based on 5G network communication. The invention aims to realize the purposes of fault isolation and power supply switching by utilizing the quick action of the fault protection terminal and transmitting an action signal to the local sectional spare power automatic switching terminal.

The technical scheme adopted by the invention for realizing the purpose is as follows:

a power distribution network protection and self-healing system based on 5G network communication comprises a protection terminal and a segmented spare power automatic switching terminal.

Further, the protection terminal is a differential protection terminal.

Furthermore, the protection terminal comprises a first terminal, a second terminal, a third terminal, a fourth terminal, a fifth terminal, a sixth terminal, a seventh terminal and an eighth terminal, wherein the first terminal and the second terminal, and the fifth terminal and the sixth terminal form line differential protection respectively by the looped network incoming line of the looped network unit, and are in communication connection through a 5G network;

the second terminal and the sixth terminal respectively form a tie line differential protection with a terminal A and a terminal B of an adjacent ring network unit, and the second terminal and the sixth terminal are communicated with each other through a 5G network;

the spare power automatic switching terminal, the second terminal, the third terminal and the fourth terminal respectively form bus protection, and the four terminals are respectively interconnected through optical fibers;

the spare power automatic switching terminal, the sixth terminal, the seventh terminal and the eighth terminal respectively form bus protection, and the fourth terminal, the sixth terminal, the seventh terminal and the eighth terminal are respectively interconnected through optical fibers.

Further, when a looped network cable of the looped network unit fails, a fault protection terminal of the looped network unit trips off a corresponding circuit breaker for fault isolation, and sends a standby switching starting signal; after the spare automatic switching terminal receives a starting spare switching signal sent by a fault protection terminal of the ring network unit, the spare automatic switching terminal confirms that the fault bus has no power supply voltage, the fault is isolated, the power supply voltage of the bus to be switched is normal, and after the spare switching device is charged, the action of a switching circuit breaker of the ring network unit is controlled after a set time period is delayed, and the bus switching power supply is completed.

Furthermore, the protection terminal is configured with an address-based network route, the CPE is accessed to the 5G network, and the CPE route is deployed in a sinking core network near the base station, so that the intercommunication of the DTU network is realized.

Furthermore, the incoming and outgoing lines of the ring network unit are all provided with differential protection terminals, and when the distribution network main line fails, the differential protection terminals act to rapidly remove the failure at the outlet; the interval protection terminal exchanges a phase overcurrent starting state, a zero sequence overcurrent starting state, a single-phase grounding line selection starting state, a phase overcurrent positive direction state, a zero sequence overcurrent positive direction state and a grounding line selection positive direction state with an adjacent interval protection terminal through a 5G-based wireless communication network to carry out looped network fault judgment, switch station bus fault judgment and feed-out line fault judgment.

Further, the ring network fault determination includes:

1) the circuit is an incoming and outgoing line;

2) starting at least one of two sides at intervals;

2) all the starting intervals on both sides are not in the opposite direction of the fault.

Further, the bus fault judgment of the switching station comprises the following steps:

1) at least one interval is started;

2) all the start intervals are not positive fault directions.

Further, when a looped network cable of the looped network unit fails, a fault protection terminal of the looped network unit trips a breaker at a protection installation position to perform fault isolation, and sends a starting standby switching signal to a next-stage sectional spare power automatic switching terminal; when a bus of a ring network unit fails, an incoming line fault protection terminal of a fault bus trips an incoming line breaker of the fault bus in parallel to perform fault isolation with an outgoing line breaker of a bus, and simultaneously trips an incoming line breaker of a next ring network unit, and the incoming line breaker of the next ring network unit sends a standby switching starting signal to a sectional standby automatic switching terminal of the stage; after the sectional spare power automatic switching terminal receives a starting spare switching signal sent by a fault protection terminal of the ring network unit, the incoming line is confirmed to be tripped, the fault bus has no power supply voltage, the power supply voltage of the bus to be switched is normal, and the standby switching equipment is charged completely, the combined sectional breaker of the ring network unit is controlled to act after a time delay set time period, and the bus is switched to supply power.

Furthermore, when a looped network cable of the looped network unit has a fault, the next-stage incoming line tripping signal starts the fast spare power automatic switching device, and selective power distribution network protection such as differential protection and dynamic self-adaptive protection T1 section action signals configured on the incoming line are transmitted to the local subsection spare power automatic switching device in a hard-open or GOOSE mode;

in the second looped network unit, after the local spare power automatic switching charging is completed, when the line where the breaker of the first bus terminal A is located starts the standby switching action, the three-line voltage of the first bus is judged, any line of the second bus has the voltage, and after the breaker of the terminal A is confirmed to be tripped, the sectionalized breaker is switched on through the sectionalized switching-on delay; when a line where a breaker B of a first female terminal is located is started and switched in, judging that three lines of a second female are not pressurized and any line of the first female is pressurized, and closing a segmented breaker through 'segmented closing delay' after the breaker B of the terminal is confirmed to be tripped;

the local spare power automatic switching function is configured at the bus-bar joint of each ring network unit, and the local bus-bar joint spare power automatic switching is started by the last cascade jump incoming line;

when a looped network cable has a fault, the fault occurs at a point A between a first terminal circuit breaker and a second terminal circuit breaker, the fault location is realized by the dynamic adaptive protection configured on the first terminal circuit breaker to trip off the first terminal circuit breaker, and the second terminal circuit breaker is tripped in parallel to finish fault isolation, a third looped network unit is started to be in-situ spare power automatic switching, the second terminal circuit breaker is determined to be tripped, a left side bus is subjected to voltage loss, a right side bus is subjected to voltage, and the switching power supply of the left side bus of the third looped network unit is finished;

when a bus fails, the fault occurs at a bus D point where the first terminal circuit breaker of the first ring network unit is located, fault location is carried out by dynamic adaptive protection configured at the third terminal circuit breaker to trip off the third terminal circuit breaker, the first terminal circuit breaker is tripped in a connected mode, the second terminal circuit breaker is tripped in a connected mode, fault isolation is completed, the third ring network unit is started to be in a standby self-switching mode, it is confirmed that the second terminal circuit breaker is tripped, the left side bus is in no-voltage state, and the right side bus is in voltage state, and power supply switching of the left side bus of the third ring network unit is completed.

The invention has the following beneficial effects and advantages:

the invention provides a system which is based on intelligent power distribution integrated terminals and can realize communication between the terminals through a 5G network, meanwhile, the information between the terminals is shared and interacted in real time, the spare power automatic switching logic is simple, the time delay is short, and the invention aims of accurate positioning of power distribution network faults and quick self-healing of power supply capacity can be realized.

The invention integrates the 5G communication technology and the current differential protection concept and applies the integration to the ring network unit of the power distribution network, thereby solving the problems that the protection level difference of the power distribution network is difficult to cooperate, the traditional differential protection depends on a special optical fiber channel, the implementation cost of the optical fiber communication engineering is high, the period is long, and the like. And the fault protection terminal is used for transmitting the action signal to the next-level spare power automatic switching terminal, the spare power automatic switching and switching-on time of each ring network unit does not need to consider the matching of level differences, including the problems of fault removal time, switching-on time and the like, the fast switching can be realized, the delay time is shorter, and the method is suitable for the ring network power supply switching of a multi-level distribution network or a subway large-partition power supply line.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic diagram of a dual ring network power supply of the present invention;

fig. 2 is a schematic diagram of the distribution and contact communication of the protection terminal and the backup power automatic switching terminal of the invention;

FIG. 3 is a schematic diagram of the differential protection terminal communication based on 5G communication according to the present invention;

fig. 4 is a schematic diagram of the backup power automatic switching logic of the present invention.

In the figure:

the automatic power switching system comprises a standby power switching terminal 10, a first terminal 11, a second terminal 12, a third terminal 13, a fourth terminal 14, a fifth terminal 21, a sixth terminal 22, a seventh terminal 23, an eighth terminal 24, a terminal A112 and a terminal B122.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, a more particular description of the invention will be rendered by reference to the appended drawings. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.

The solution of some embodiments of the invention is described below with reference to fig. 1-4.

Example 1

The invention relates to a power distribution network protection and self-healing system based on 5G network communication, which is a power distribution network protection system based on 5G network communication and suitable for a power distribution network looped network line.

As shown in fig. 2, fig. 2 is a schematic diagram of the distribution and contact communication of the protection terminal and the backup power automatic switching terminal according to the present invention. Is a typical design topological diagram of a ring network line of a power distribution network.

The protection and self-healing system of the invention comprises: the system comprises a protection terminal and a sectional spare power automatic switching terminal. The protection terminal is a differential protection terminal.

Specifically, the system comprises 9 protection terminals: one of the backup power automatic switching terminals 10 and the others are protection terminals.

According to the invention, the first terminal 11 and the second terminal 12 of the looped network incoming line of the looped network unit, and the fifth terminal 21 and the sixth terminal 22 respectively form line differential protection, and the two terminals are respectively in communication connection through a 5G network.

The second terminal 12 and the sixth terminal 22 respectively form a tie line differential protection with the terminal a112 and the terminal B122 of the adjacent ring network unit, and the two are respectively communicated through a 5G network;

the spare power automatic switching terminal 10, the second terminal 12, the third terminal 13 and the fourth terminal 14 respectively form bus protection, and the four terminals are respectively interconnected through optical fibers.

The spare power automatic switching terminal 10, the sixth terminal 22, the seventh terminal 23 and the eighth terminal 24 respectively form bus protection, and the four terminals are respectively interconnected through optical fibers.

When the looped network cable has a fault, the fault protection terminal of the looped network unit trips off the corresponding circuit breaker to perform fault isolation, and sends a standby switching starting signal. After the spare automatic switching terminal receives a starting spare switching signal sent by a fault protection terminal of the ring network unit, the spare automatic switching terminal confirms that the fault bus has no power supply voltage, the fault is isolated, the power supply voltage of the bus to be switched is normal, and after the spare switching device is charged, the action of a switching circuit breaker of the ring network unit is controlled after a set time period is delayed, and the bus switching power supply is completed.

As shown in fig. 3, fig. 3 is a schematic diagram of the differential protection terminal based on 5G communication according to the present invention. And configuring an address-based network route at the protection terminal, accessing the CPE to the 5G network, deploying the CPE route in a sinking core network near the base station, and realizing the intercommunication of the DTU network.

The ring network unit inlet and outlet lines are all provided with differential protection terminals, so that the ring network unit inlet and outlet lines have a differential protection function, and when a distribution network main line fails, the differential protection terminals act to rapidly remove the failure at an outlet; the interval protection terminal exchanges a phase overcurrent starting state, a zero sequence overcurrent starting state, a single-phase grounding line selection starting state, a phase overcurrent positive direction state, a zero sequence overcurrent positive direction state and a grounding line selection positive direction state with an adjacent interval protection terminal through a 5G-based wireless communication network to carry out looped network fault judgment, switch station bus fault judgment and feed-out line fault judgment.

The distribution network main line comprises a connecting line between the ring network units.

The looped network fault judgment comprises the following steps:

1) the circuit is an incoming and outgoing line;

2) starting at least one of two sides at intervals;

2) all the starting intervals on both sides are not in the opposite direction of the fault.

The bus fault judgment of the switching station comprises the following steps:

1) at least one interval is started;

2) all the start intervals are not positive fault directions.

Each protection terminal collects state quantities such as the current and the current of the local side and the position of a switch, receives sampling data such as the current and the voltage of each side line through a 5G network, and synchronizes CPE and the protection terminals in the area by using an internal synchronous clock or a GPS external clock; each interval protection terminal performs local sampling and timestamping on the interval at an absolutely uniform sampling starting moment, unifies sampling serial numbers, encapsulates GOOSE and SV into a UDP message format and sends the UDP message format to a 5G communication network through CPE; and each interval protection terminal receives other interval sampling data with sampling serial numbers from the 5G communication network, synchronizes data at each side by adopting a serial number alignment mode and performs differential calculation.

For the protection terminal which communicates in an optical fiber mode, local sampling and time marking are carried out on the interval at an absolutely uniform sampling starting moment, and after sampling serial numbers are unified, the interval is transmitted to other adjacent intervals through optical fibers in GOOSE and SV message formats respectively; each protection terminal receives other sampling data with sampling serial numbers at intervals, synchronizes data on each side by adopting a serial number alignment mode, and performs differential calculation.

Example 2

The invention also provides an embodiment, which is a power distribution network protection and self-healing system based on 5G network communication and is suitable for a power distribution network ring network line.

When a looped network cable fails, a fault protection terminal of a looped network unit trips off a breaker at a protection installation position to perform fault isolation, and sends a starting standby switching signal to a next-stage sectional spare power automatic switching terminal; when a bus of a ring network unit fails, an incoming line fault protection terminal of a fault bus trips an incoming line breaker of the fault bus in parallel to perform fault isolation with an outgoing line breaker of a bus, and simultaneously trips an incoming line breaker of a next ring network unit, and the incoming line breaker of the next ring network unit sends a standby switching starting signal to a sectional standby automatic switching terminal of the stage; after the sectional spare power automatic switching terminal receives a starting spare switching signal sent by a fault protection terminal of the ring network unit, the incoming line is confirmed to be tripped, the fault bus has no power supply voltage, the power supply voltage of the bus to be switched is normal, and the standby switching equipment is charged completely, the combined sectional breaker of the ring network unit is controlled to act after a time delay set time period, and the bus is switched to supply power.

As shown in fig. 1, fig. 1 is a schematic diagram of a dual-ring network power supply mode of the present invention, and is a typical design topological diagram of a ring network line of a power distribution network.

When the looped network cable has a fault, the next stage of incoming line trip signal starts the fast spare power automatic switching device, and selective power distribution network protection such as differential protection and dynamic self-adaptive protection T1 section action signals configured on the incoming line are transmitted to the local subsection spare power automatic switching device in a hard switching-in or GOOSE mode.

Taking the second looped network unit as an example, after the local backup power automatic switching charging is completed, when the line where the breaker of the first bus terminal A112 is located starts the switching-in action, the three lines of the first bus are not pressurized and any line of the second bus is pressurized, and after the breaker of the terminal A112 is determined to be tripped, the circuit is switched on and off through 'section switching-on delay'; when the line where the first female terminal B122 breaker is located is started to be switched into operation, the second female three-line voltage is not applied and any line of the first female is pressed, and the sectionalized breaker is closed through 'sectionalized closing delay' after the fact that the terminal B122 breaker is tripped is confirmed. As shown in fig. 4, fig. 4 is a schematic diagram of the backup power automatic switching logic of the present invention.

The spare power automatic switching closing time of each ring network unit does not need to consider the matching of the level difference, and the method is suitable for switching power supply of a multi-level distribution network or a subway large-partition ring network power supply line.

And the local spare power automatic switching function is configured at the bus-bar joint of each ring network unit, and the local bus-bar joint spare power automatic switching is started by the last cascade jump incoming line.

(1) And (4) ring network cable failure.

The fault occurs at the point A between the first terminal 11 circuit breaker and the second terminal 12 circuit breaker, the fault location is protected by the dynamic adaptation configured at the first terminal 11 circuit breaker to complete the trip-out of the first terminal 11 circuit breaker, the second terminal 12 circuit breaker is tripped in parallel to complete fault isolation, the third ring network unit is started to be in spare power automatic switching on the spot, the second terminal 12 circuit breaker is confirmed to be tripped out, the left side bus is in voltage loss, the right side bus is in voltage, and the power supply switching of the left side bus of the third ring network unit is completed.

(2) And (6) bus failure.

When a bus fails, the fault occurs at a bus D point where a breaker of a second terminal 12 of the first ring network unit is located, fault location is achieved by means of dynamic adaptive protection configured at the breaker of a third terminal 13 to trip off the breaker of the third terminal 13, a breaker of the first terminal 11 is tripped in a connected mode, a breaker of the second terminal 12 is tripped in a parallel mode, fault isolation is achieved, the third ring network unit is started to be in a standby power automatic switching mode on site, the fact that the breaker of the second terminal 12 is tripped, the voltage of a bus on the left side is lost, the voltage of the bus on the right side is pressed is confirmed, and power supply switching of the bus on the left side of the third ring network unit is achieved.

In summary, the invention provides a power distribution network protection and self-healing system based on 5G network communication and applicable to a power distribution network ring network line, and the 5G communication technology and the current differential protection concept are fused and applied to a power distribution network ring network unit, so that the problems that the power distribution network protection level difference is difficult to cooperate, the traditional differential protection depends on a special optical fiber channel, the implementation cost of an optical fiber communication project is high, the period is long, and the like are solved. When the looped network cable has a fault, the fault protection terminal of the looped network unit trips off the corresponding circuit breaker to perform fault isolation, and sends a standby switching starting signal. After the sectional spare power automatic switching terminal receives a starting spare switching signal sent by a fault protection terminal of the ring network unit, the fact that a fault bus has no power supply voltage is confirmed, the fault is isolated, the power supply voltage of the bus to be switched is normal, and the standby switching equipment is charged completely, the action of a switching breaker of the ring network unit is controlled after a time delay set time period, bus switching power supply is completed, power supply fast switching is achieved, and the sectional spare power automatic switching terminal is suitable for switching power supply of a multi-stage distribution network or a subway large-partition ring network power supply line.

In the present invention, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. The terms "connected" and "fixed" are to be construed broadly, e.g., "connected" may be a fixed connection, a removable connection, or an integral connection. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the description of the present invention, it is to be understood that the indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the indicated devices or units must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present specification, the description of the terms "one embodiment," "some embodiments," or the like, means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.