CN108493906A - Decentralized bus protection handset repair method and decentralized bus protection system - Google Patents

Abstract

The invention relates to a distributed bus protection sub-machine maintenance method and a distributed bus protection system. The distributed bus protection includes N sub-machines, N≥2, and each sub-machine is connected to each other through a communication line, and each sub-machine is provided with N maintenance Press plate, when a certain sub-machine is overhauled, the maintenance sub-machine is put into all the maintenance pressure plates, and other sub-machines are put into the corresponding maintenance pressure plate of the maintenance sub-machine, and then the maintenance sub-machine is overhauled, without affecting the information interaction between other sub-machines, It also does not affect the normal operation of other sub-machines. After the overhaul is completed, each sub-machine withdraws from the corresponding overhaul pressing plate. Therefore, by setting the maintenance platen and the input control of the maintenance platen according to the number of sub-units in the distributed busbar protection sub-units, the information interaction between other sub-units is not affected, and the problem of maintenance of a single sub-unit of distributed busbar protection is solved. Moreover, the method has simple software processing, high reliability, and is easy to implement, and can improve the reliability of the in-situ busbar protection device.

Description

Distributed busbar protection sub-machine maintenance method and distributed busbar protection system

technical field

The invention relates to a distributed busbar protection sub-unit maintenance method and a distributed busbar protection system, and belongs to the technical field of electric power system relay protection.

Background technique

The State Grid Corporation has summarized the operation of the protection and control equipment of the smart substation in recent years, combined with the test situation of the network connection test of the China Electric Power Research Institute, and put forward suggestions for optimization and improvement in the following main aspects: First, the ease of operation and maintenance of the protection and control devices The usability and convenience need to be improved; the second is the safety and reliability of the relay protection system, especially the requirement that the damage protection of a single component cannot be misoperated. The delay of sampling transmission and the increase of subsequent links such as intelligent terminals lead to an increase in the action time of the entire group of relay protection compared with conventional substations; fourth, the management and control of intelligent substation engineering configuration files need to be improved, and intelligent substations need to be improved from engineering design to configuration , Commissioning and acceptance stages rely heavily on equipment manufacturers, and various configuration files and configuration downloading tools are different, which seriously affects the construction cycle of smart substation projects, and prevents operation and maintenance personnel from independently completing relevant maintenance operations. In this context, the Science and Technology Department of the State Grid Corporation of China and the National Investigation Center successively organized related equipment manufacturers and some provincial companies to carry out research on innovative schemes for the layout of secondary equipment in smart substations, and proposed miniaturization of relay protection devices, Localized unprotected installation mode.

The Chinese patent application document with the application publication number CN101699706A discloses a method for processing the maintenance state of a relay protection device by a substation of a fault information system. Manually put in the hard pressing plates corresponding to the interval, and withdraw the corresponding hard pressing plates manually when the maintenance of the relay protection device is completed. In addition, the maintenance status of the corresponding relay protection device is judged through the status information of the hard plate, and sent to the substation.

In recent years, my country's smart substation has developed rapidly, which has strongly promoted the innovation of relay protection technology. Miniaturization and in-situ protection are the current development direction of smart substation relay protection technology. Component protection such as on-site transformer protection and busbar protection adopts a distributed structure, which is composed of multiple on-site protection sub-machines, and each sub-machine shares information and operates cooperatively. Each sub-machine is responsible for completing the acquisition of several interval analog quantities and switching values, and at the same time receives the collected data of other sub-machines, and then independently completes the protection logic operation and tripping exit.

Therefore, the processing method of the above-mentioned patent application is only applicable to the communication between the sub-station and the master station, and cannot be applied to distributed systems such as distributed busbar protection.

Contents of the invention

The object of the present invention is to provide a method for overhauling the sub-units of distributed busbar protection, which is used for overhauling the subunits of distributed busbar protection. The invention also provides a distributed busbar protection system.

To achieve the above object, the present invention includes the following technical solutions.

A method for overhauling distributed busbar protection subunits. The distributed busbar protection includes N subunits, N≥2. The subunits are connected to each other through communication lines, and each subunit can obtain relevant information of other subunits and complete the operation independently. All protection functions, each sub-machine is equipped with N maintenance pressure plates, and each maintenance pressure plate in each sub-machine corresponds to each sub-machine one by one; when a certain sub-machine is overhauled, the maintenance sub-machine is put into the inspection pressure plate corresponding to all sub-machines , each sub-machine except the maintenance sub-machine is put into the maintenance pressure plate corresponding to the maintenance sub-machine, and then the maintenance sub-machine is overhauled, and when the maintenance is completed, the maintenance sub-machine withdraws from all the maintenance pressure plates, All sub-machines except the sub-machine for inspection withdraw from the inspection pressing plate corresponding to the sub-machine for inspection.

The sub-machines are connected to each other through communication lines. Each sub-machine can obtain the relevant information of other sub-machines and complete all protection functions independently. As many sub-machines as the protection has, each sub-machine has as many maintenance pressure plates. When a certain When a sub-machine is overhauled, the maintenance sub-machine is put into the inspection pressure plate corresponding to all the sub-machines, and each sub-machine except the maintenance sub-machine is put into the inspection pressure plate corresponding to the inspection sub-machine, and then the maintenance sub-machine is overhauled. Affect the information interaction between other sub-machines, the information interaction between the sub-machines except the maintenance sub-machine will not be affected, and the normal operation of other sub-machines will not be affected, so the maintenance of a single sub-machine will not affect the normal protection run. After the inspection is completed, the inspection sub-machine withdraws from all inspection pressing plates, and each sub-machine except the inspection sub-machine withdraws from the inspection pressing plate corresponding to the inspection sub-machine. Therefore, this maintenance method is suitable for distributed protection, and is mainly used in the local distributed bus protection device of intelligent substation. By setting the maintenance pressure plate and the input control of the maintenance pressure plate according to the number of sub-machines in the distributed bus protection sub-machine, It does not affect the information interaction between other sub-units, and solves the problem of maintenance of a single sub-unit of distributed busbar protection. Moreover, the method has simple software processing, high reliability, and is easy to implement, and can improve the reliability of the in-situ busbar protection device.

Further, when the maintenance sub-machine is put into the maintenance pressure plate corresponding to all sub-machines, only the analog quantity information corresponding to the maintenance sub-machine is received, and the analog quantity information corresponding to other sub-machines is not received; Any sub-machine other than the inspection sub-machine, when the inspection platen corresponding to the inspection sub-machine is put into the sub-machine, the sub-machine will no longer receive the analog information corresponding to the inspection sub-machine, and each sub-machine except the maintenance sub-machine The analog information exchange between slaves is not affected.

Since the primary device corresponding to the sub-machine has been disconnected when the inspection pressure plate of a single sub-machine is put into operation, there is no current in the secondary circuit, so other sub-machines no longer receive the analog information corresponding to the sub-machine for maintenance, and will not affect the busbar protection The normal operation of the protection, that is, the maintenance of a single sub-machine will not affect the normal operation of the protection. Moreover, when the sub-unit is overhauled, it is necessary to apply a current through a relay protection tester and other equipment to check the correctness of the current circuit and protection performance of the overhauled sub-unit. If other sub-units receive the analog information corresponding to the overhauled sub-unit, it may cause the normal operation of the bus The protection is malfunctioning, so other slave machines cannot receive the analog information corresponding to the maintenance slave machine. The maintenance sub-unit only receives its own analog information, which can isolate the influence of other sub-units, and is used for the inspection of busbar protection performance. Therefore, the interaction of analog information between the sub-machines except the maintenance sub-machine is not affected, and the maintenance of a single sub-machine will not affect the normal operation of the protection.

Further, when the maintenance sub-machine is put into the maintenance pressure plate corresponding to all sub-machines, the fixed value and pressure plate of the maintenance sub-machine are inconsistent with other sub-machines, and the alarm is exited, and the other sub-machines and the maintenance sub-machine If the fixed value and the pressure plate are inconsistent, the judgment logic exits.

Further, each sub-machine calculates its fixed value and pressing plate into CRC and transmits it to other sub-machines, and each sub-machine compares the corresponding CRC information to judge the consistency of the fixed value and pressing plate.

A distributed bus protection system, including N sub-units, N≥2, each sub-unit is connected to each other through communication lines, each sub-unit can obtain relevant information of other sub-units and independently complete all protection functions, each sub-unit N inspection pressure plates are provided, and each inspection pressure plate in each sub-machine corresponds to each sub-machine one by one; All other sub-machines are put into the inspection platen corresponding to the inspection sub-machine, and then the inspection sub-machine is overhauled. Each sub-machine outside withdraws from the maintenance pressing plate corresponding to the said maintenance sub-machine.

Further, when the maintenance sub-machine is put into the maintenance pressure plate corresponding to all sub-machines, only the analog quantity information corresponding to the maintenance sub-machine is received, and the analog quantity information corresponding to other sub-machines is not received; Any sub-machine other than the inspection sub-machine, when the inspection platen corresponding to the inspection sub-machine is put into the sub-machine, the sub-machine will no longer receive the analog information corresponding to the inspection sub-machine, and each sub-machine except the maintenance sub-machine The analog information exchange between slaves is not affected.

Further, when the maintenance sub-machine is put into the maintenance pressure plate corresponding to all sub-machines, the fixed value and pressure plate of the maintenance sub-machine are inconsistent with other sub-machines, and the alarm is exited, and the other sub-machines and the maintenance sub-machine If the fixed value and the pressure plate are inconsistent, the judgment logic exits.

Further, each sub-machine calculates its fixed value and pressing plate into CRC and transmits it to other sub-machines, and each sub-machine compares the corresponding CRC information to judge the consistency of the fixed value and pressing plate.

Further, in order to realize high-speed and high-reliability data transmission, each sub-machine is connected through optical fiber Ethernet to form a bidirectional double-ring network, and each sub-machine can obtain relevant information of other sub-machines through the bidirectional double-ring network.

Furthermore, each sub-machine is fixedly connected to M bays, and is responsible for the collection of analog and switching values corresponding to M bays and the phase-separated tripping outlets, M≥1.

Further, each slave machine can issue SV messages, send and receive GOOSE and MMS messages, wherein, the SV message contains the analog information of the interval collected by the corresponding slave machine, and the message sent by GOOSE contains the trip signal of the whole set of busbar protection and the corresponding The switching value information of the intervals collected by the sub-machine, GOOSE receives the message as the start failure signal of all intervals.

Description of drawings

Figure 1 is a schematic diagram of the layout of distributed busbar protection sub-units.

Detailed ways

Embodiment of Distributed Busbar Protection System

In this embodiment, the distributed busbar protection system (referred to as distributed busbar protection) adopts direct cable sampling and direct cable tripping, uses standard connectors for external input and output, and is installed close to the primary equipment on site. Therefore, the distributed bus protection sub-machine maintenance method adopted in the distributed bus protection can be applied to the distributed bus protection device arranged close to the primary equipment.

Distributed busbar protection includes N busbar protection sub-units (hereinafter referred to as sub-units), N≥2, all sub-units are identical, and the specific number of N is set according to actual needs. In this embodiment, the distributed busbar protection adopts a building block design, and a maximum of 4 slave units are configured. The sub-machines are connected to each other through communication lines, and each sub-machine can obtain relevant information of other sub-machines. In this embodiment, the sub-machines are connected through Gigabit optical fiber Ethernet to form a highly reliable seamless redundancy The internal dedicated two-way double-ring network, each sub-machine can obtain the relevant information of other sub-machines through the bi-directional double-ring network, and each sub-machine can independently complete all protection functions. In addition, each sub-machine is fixedly connected to M intervals, and is responsible for the collection of analog and switching values corresponding to M intervals and the phase-separated tripping exit. M≥1, and the value of M is set according to the actual situation. In this embodiment , M=8, then, each sub-machine is fixedly connected to 8 bays, and is responsible for the acquisition of the analog and switching values corresponding to the 8 bays and the phase-splitting tripping outlets of the corresponding bays. Each sub-machine has the output function of SV, GOOSE, and MMS three-in-one optical port. The optical port adopts a 100M optical fiber interface. The SV data output format is IEC 61850-9-2, and the sampling rate is 4kHz. All sub-machines are connected to the protection private network, and each sub-machine can issue SV messages and send and receive GOOSE and MMS messages. Among them, the SV message contains the analog information of the corresponding sub-machine The trip signal of the busbar protection and the switching value information of the intervals collected by the corresponding sub-units, the messages received by GOOSE are the start-up failure signals of all intervals.

Fig. 1 is a schematic diagram of a specific arrangement of sub-machines for distributed busbar protection, of course, the present invention is not limited to this specific implementation.

Each sub-machine is equipped with N inspection pressure plates, that is to say, each sub-machine is equipped with sub-machine inspection pressure plates according to the maximum number of sub-machines, how many sub-machines there are, how many inspection pressure plates are set for each sub-machine, and the number of inspection pressure plates in each sub-machine Each maintenance pressing plate corresponds to each sub-machine one by one. Since in this embodiment, the in-situ distributed busbar protection is configured by a maximum of 4 sub-machines, then each sub-machine is provided with a total of 4 maintenance platen.

Most of the existing busbar protection adopts a centralized arrangement, that is, one protection device is used to complete all protection functions, so there is no problem of single sub-unit maintenance, while distributed busbar protection is completed by multiple sub-units. There is the problem of single sub-machine maintenance during maintenance or device failure.

When a certain sub-machine is overhauled (the overhauled sub-machine is called an overhaul sub-machine), the overhaul sub-machine is put into the overhaul platen corresponding to all sub-machines, and all sub-machines except the overhaul sub-machine are put into the overhaul sub-machine. The maintenance pressure plate corresponding to the sub-machine, for example: when sub-machine 2 needs to be overhauled, sub-machine 2 is the maintenance sub-machine, then sub-machine 2 is put into the maintenance pressure plate corresponding to sub-machine 1, sub-machine 2, sub-machine 3 and sub-machine 4, Sub-machine 1, sub-machine 3 and sub-machine 4 are all put into the maintenance pressure plate corresponding to sub-machine 2. The processing method of putting all the inspection pressure plates into the maintenance sub-machine is different from that of other sub-machines except the maintenance sub-machine. , that is, when the sub-machine 2 is put into the inspection platen corresponding to all sub-machines, it only receives the analog information corresponding to the inspection sub-machine, and does not receive the analog information corresponding to other sub-machines. This processing method can verify the protection of the maintenance sub-machine. Action behavior, further, the specific verification process of the protection action behavior of the maintenance sub-machine is: when the sub-machine is overhauled, a current is applied through the relay protection tester, and whether the sampling value of the device is consistent with the applied current through the management unit, and the sub-machine can be checked. The correctness of the electromechanical current circuit; moreover, verify the protection action behavior by applying the corresponding current, for example: the differential protection should operate reliably when the starting current setting value of 1.025 times the differential protection is applied, and the time difference when the starting current setting value of the differential protection is applied is 0.975 times The dynamic protection should be reliable and not act. For any sub-machine except the maintenance sub-machine, that is, sub-machine 1, sub-machine 3 or sub-machine 4, when the inspection platen corresponding to the overhaul sub-machine is put into operation, that is, when the inspection platen corresponding to sub-machine 2 is put into operation, these except The slave machines other than the maintenance slave machine no longer receive the analog quantity information corresponding to the maintenance slave machine, and the interaction of analog quantity information between these slave machines (that is, all slave machines except the maintenance slave machine) is not affected.

Therefore, since the distributed busbar protection is completed by multiple sub-units to jointly complete all protection functions, there is a problem of single sub-unit maintenance when an equipment maintenance or device failure occurs. Each sub-machine is equipped with N inspection pressure plates corresponding to N sub-machines respectively. When a sub-machine is overhauled, the maintenance pressure plates of all sub-machines in the inspection sub-machine need to be put in. At this time, the maintenance sub-machine only receives its own simulation. It does not receive the analog quantity information corresponding to other sub-machines; other sub-machines only need to be put into the inspection platen of the inspection sub-machine, and at this time other sub-machines no longer receive the analog information corresponding to the inspection sub-machine, except for the inspection sub-machine The interaction of analog information between sub-machines other than the sub-machine is not affected, so the maintenance of a single sub-machine will not affect the normal operation of the protection. Moreover, when the maintenance pressure plate of a single sub-machine is put into operation, the primary equipment corresponding to the sub-machine has been disconnected, and there is no current in the secondary circuit, so other sub-machines no longer receive the analog information corresponding to the sub-machine for maintenance, and will not affect the bus normal operation of the protection. Because when the sub-machine is overhauled, it is necessary to apply a current through the relay protection tester to check the correctness of the current circuit and protection performance of the overhauled sub-machine. If other sub-machines receive the analog information corresponding to the overhauled sub-machine, it may cause the normal operation of the busbar protection to malfunction. , so other sub-machines cannot receive the analog information corresponding to the maintenance sub-machine. The maintenance sub-unit only receives its own analog information, which can isolate the influence of other sub-units, and is used for the inspection of busbar protection performance.

Distributed busbar protection is completed by multiple sub-units to complete all protection functions, and the setting value of each sub-unit is exactly the same as the pressure plate during normal operation. When the setting value or pressure plate of a sub-machine is inconsistent with other sub-machines, it indicates that the setting value or pressure plate of this sub-machine is abnormal, which may cause protection malfunction. Therefore, when the setting value and pressure plate of each sub-machine are inconsistent, blocking protection is required. Therefore, under normal circumstances, that is, when the system is running normally, it is necessary to judge the inconsistency of the fixed value and the pressure plate among the sub-machines and give an alarm. When the inspection sub-machine is put into the inspection pressure plate corresponding to all the sub-machines, it is also necessary to judge the inconsistency of the fixed value and the pressure plate. Value, pressure plate inconsistent judgment alarm exit, other sub-machines and maintenance sub-machine set value, pressure plate inconsistent judgment logic exit. There is the problem of a single sub-machine overhaul when an equipment overhaul or device failure occurs. When a sub-machine is overhauled, all the sub-machines in the sub-machine are put into the maintenance pressure plate, and other sub-machines only need to put in the maintenance pressure plate of the sub-machine. However, the maintenance sub-unit still needs to complete the busbar protection function test independently, so it is no longer necessary to judge whether the fixed value and pressure plate of the maintenance sub-unit and other sub-units are consistent.

Furthermore, each sub-machine calculates its own fixed value and pressure plate into CRC and then transmits it to other sub-machines through the internal dedicated two-way double-ring network, and each sub-machine compares the corresponding CRC information to determine the consistency of the fixed value and pressure plate, as follows A specific implementation process is given: each sub-machine takes its own fixed value and pressure plate as a total data block, and uses the cyclic redundancy check code to calculate the CRC: after the K-bit information code, the R-bit check code is spliced , the entire code length is N bits, so this code is also called (N, K) code. For a given (N, K) code, it can be proved that there exists a polynomial G(x) whose highest power is NK=R. The check code of K-bit information can be generated according to G(x), and G(x) is called the generator polynomial of this CRC code. The specific generation process of the check code is as follows: Assuming that the information to be sent is represented by a polynomial C(x), shift C(x) to the left by R bits (can be expressed as C(x)*2R), so that the right side of C(x) The R bit will be vacated, which is the position of the check code. The remainder obtained by dividing C(x)*2R by the generator polynomial G(x) is the check code. Any code composed of binary bit strings can be in one-to-one correspondence with a polynomial whose coefficients only take values of '0' and '1'. For example: the polynomial corresponding to the code 1010111 is x ⁶ +x ⁴ +x ² +x+1, and the polynomial is x ⁵ +x ³ +x ² +x+1 corresponding to the code 101111. Each sub-machine independently determines the value and the consistency of the pressure plate through the CRC information. After each sub-machine receives the CRC information of other N-1 sub-units, it compares its CRC information with other sub-units respectively. If the pressure plate is not put into use, the rated value will be reported, and the pressure plate will be inconsistent and locked for protection.

Then, the overhaul sub-machine is overhauled.

When the maintenance is completed, the maintenance sub-unit exits all the maintenance pressure plates, and each sub-unit except the maintenance sub-unit exits the maintenance pressure plate corresponding to the maintenance sub-unit, and each sub-unit normally participates in the logical discrimination of the distributed busbar protection.

Specific embodiments have been given above, but the present invention is not limited to the described embodiments. The basic idea of the present invention lies in the maintenance method of the distributed busbar protection sub-machine, which is not limited to the system structure applied by the method, that is, it is not limited to the specific system structure given above, any distributed busbar based on the maintenance method systems are within the protection scope of the present invention. Changes, modifications, substitutions and variations to the implementations without departing from the principle and spirit of the present invention still fall within the protection scope of the present invention.

Embodiment of Distributed Busbar Protection Subunit Maintenance Method

This embodiment provides a method for overhauling distributed busbar protection subunits. The distributed busbar protection includes N subunits, N≥2, and the subunits are connected to each other through communication lines. Each subunit can obtain the relevant information and independently complete all protection functions, each sub-machine is equipped with N inspection pressure plates, and each inspection pressure plate in each sub-machine corresponds to each sub-machine one by one; when a certain sub-machine is overhauled, the maintenance sub-machine is put into all sub-machines Corresponding inspection pressure plate, each sub-machine except the inspection sub-machine is put into the inspection pressure plate corresponding to the inspection sub-machine, and then the inspection sub-machine is inspected, when the inspection is completed, the inspection sub-machine withdraws from all inspection pressure plates, except for the maintenance Each sub-machine except the sub-machine withdraws from the inspection pressing plate corresponding to the inspection sub-machine.

Since the maintenance method has been described in detail in the above system embodiments, it will not be described in detail here.

Claims (10)

1. A distributed bus protection sub-machine maintenance method, distributed bus protection includes N sub-machines, N≥2, each sub-machine is connected to each other through communication lines, each sub-machine can obtain the relevant information of other sub-machines and Independently complete all protection functions, the feature is that each sub-machine is equipped with N inspection pressure plates, and each inspection pressure plate in each sub-machine corresponds to each sub-machine one by one; when a certain sub-machine is overhauled, the maintenance sub-machine is put into all The inspection pressing plate corresponding to the sub-machine, each sub-machine except the inspection sub-machine is put into the inspection pressing plate corresponding to the inspection sub-machine, and then the maintenance sub-machine is overhauled, and when the maintenance is completed, the maintenance sub-machine Exit all inspection pressing plates, and each sub-machine except the inspection sub-machine withdraws from the inspection pressing plate corresponding to the inspection sub-machine. 2. The distributed busbar protection sub-machine maintenance method according to claim 1, characterized in that when the maintenance sub-machines are put into the maintenance pressure plates corresponding to all sub-machines, only the analog information corresponding to the maintenance sub-machines is received , does not receive the analog information corresponding to other sub-machines; for any sub-machine except the maintenance sub-machine, when the maintenance pressure plate corresponding to the maintenance sub-machine is put into the sub-machine, the sub-machine will no longer receive the maintenance The analog quantity information corresponding to the sub-machine, and the interaction of analog quantity information among the sub-machines except the maintenance sub-machine is not affected. 3. The method for overhauling distributed busbar protection sub-units according to claim 1 or 2, characterized in that, when the overhaul sub-units are put into the overhaul pressure plates corresponding to all sub-units, the overhaul sub-unit and other sub-units The fixed value and pressure plate inconsistent judgment alarm exit, and the fixed value and pressure plate inconsistency judgment logic of other sub-machines and the maintenance sub-machine exit. 4. The method for overhauling distributed busbar protection sub-units according to claim 3, wherein each sub-unit calculates its respective fixed value and pressing plate into a CRC and then transmits it to other sub-units, and each sub-unit compares the corresponding The CRC information is used to determine the value and the consistency of the pressure plate. 5. A distributed busbar protection system, characterized in that it includes N sub-machines, N≥2, each sub-machine is connected to each other through a communication line, and each sub-machine can obtain relevant information of other sub-machines and independently complete all Protection function, each sub-machine is equipped with N inspection pressure plates, and each inspection pressure plate in each sub-machine corresponds to each sub-machine one by one; All sub-machines except the maintenance sub-machine are put into the maintenance pressing plate corresponding to the maintenance sub-machine, and then the maintenance sub-machine is overhauled, and when the maintenance is completed, the maintenance sub-machine withdraws from all the maintenance pressing plates, except All sub-machines other than the sub-machines for inspection withdraw from the inspection pressing plate corresponding to the sub-machines for inspection. 6. The distributed busbar protection system according to claim 5, characterized in that when the maintenance sub-units are put into the maintenance pressure plates corresponding to all sub-units, only the analog information corresponding to the maintenance sub-units is received, and no Analog quantity information corresponding to other sub-machines; for any sub-machine except the maintenance sub-machine, when the maintenance pressing plate corresponding to the maintenance sub-machine is put into the sub-machine, the sub-machine will no longer receive the information corresponding to the maintenance sub-machine. The analog quantity information of each sub-machine except the maintenance sub-machine is not affected. 7. The distributed busbar protection system according to claim 5 or 6, characterized in that, when the maintenance sub-unit is put into the maintenance pressure plate corresponding to all sub-units, the fixed value of the maintenance sub-unit and other sub-units 1. The discriminant alarm for the inconsistency of the pressing plate exits, and the setting value of the other sub-machines and the maintenance sub-machine, and the discriminant logic of the inconsistency of the pressing plate exit. 8. The distributed busbar protection system according to claim 7, characterized in that each sub-machine calculates its own fixed value and pressure plate into CRC and then transmits it to other sub-machines, and each sub-machine compares the corresponding CRC information Carry out the determination of the fixed value and the consistency of the pressure plate. 9. according to the described distributed bus protection system of claim 5 or 6 or 8, it is characterized in that, each sub-machine is connected by optical fiber Ethernet to form a bidirectional double-ring network, and each sub-machine can obtain Information about other slaves. 10. The distributed busbar protection system according to claim 5 or 6 or 8, wherein each sub-machine is fixedly connected to M intervals, and is responsible for the acquisition and phase separation of analog quantities and switching quantities corresponding to M intervals Trip exit, M≥1.