阅读说明：本技术 三端差动通道异常情况下远跳的处理方法 (Method for processing far jump under abnormal condition of three-terminal differential channel ) 是由 韩晋 程淋伟 徐东方 张利峰 张祝威 于 2021-06-01 设计创作，主要内容包括：本发明公开了三端差动通道异常情况下远跳的处理方法,本方法包含以下内容：三端差动各侧均将两侧的通道状态传送给对侧,当有一侧通道故障时,通过主机切换和转发远跳命令,使通道异常的两个主机之间的远跳命令可以互传,实现快速保护,通信环内的差动保护和远跳保护都能正确执行,而不受通道故障的影响。本发明通过主机转发远跳命令,消除了三端差动在一通道异常的情况下远跳动作有死区的问题,使得在这种工况下,远跳也能快速动作,提高了现场的运行可靠性。(The invention discloses a method for processing far jump under the condition of three-terminal differential channel abnormality, which comprises the following steps: when one side channel has a fault, the remote jump commands between two hosts with abnormal channels can be mutually transmitted through switching and forwarding the remote jump commands by the hosts, so that the rapid protection is realized, and the differential protection and the remote jump protection in the communication ring can be correctly executed without being influenced by the channel fault. The invention transmits the far jump command through the host, eliminates the problem that the far jump has dead zone under the condition that the three-terminal differential motion is abnormal in one channel, ensures that the far jump can also act quickly under the working condition, and improves the operation reliability of the site.)

1. The method for processing the long jump under the abnormal condition of the three-terminal differential channel is characterized by comprising the following steps of:

step 1, each device always monitors the state of each channel under normal conditions and transmits the channel state to all connected protection devices;

step 2, when one channel is abnormal, the host automatically switches to the host with normal channels on two sides;

step 3, the switched host forwards the received long jump command to the adjacent two-side devices, and simultaneously sends the long jump command of the host side to the two-side devices;

and 4, the device receiving the long jump command executes the long jump command according to the set conditions.

2. The method as claimed in claim 1, wherein in step 1, when all channels are normal, the host is determined by the identification code.

3. The method as claimed in claim 1, wherein in step 3, if there is a channel abnormality, the host will forward as long as any device in the communication ring sends out the far-jump signal.

Technical Field

The invention belongs to the technical field of electric power systems, relates to a method for processing line protection long jump of an electric power system, and particularly relates to a method for transmitting long jump when a channel on one side of a three-terminal differential mechanism is abnormal.

Background

When a fault occurs between the line side CT and the line switch, the fault point is in the bus differential protection action range, and the fault bus operation switch is cut off through the quick action of the fault point, but for the opposite side transformer substation, the fault point is not in the line protection range, so that the fault cannot be quickly removed, and the fault is cut off through the backup protection of the opposite side line protection device in a delayed mode, and the stable operation of the system is influenced. To achieve fast protection action, a long jump function is provided, and after the mother-difference and failure protection actions, TJR are activated, the opposite side switch is jumped far.

The function and implementation of the long jump are as follows: with three-terminal differential, if each channel, M, N in fig. 1, is normal with P, each device sends its own remote jump command to the neighboring device. When a certain channel is abnormal, such as the channel between N and P in fig. 2, the host switches to the side where the channels on both sides are intact, i.e., the side M, and the differential protection function is normal. However, if a fault occurs on the line on the N side and falls into the bus protection range, and when the protection of the M and P sides adjacent to each other by means of joint tripping is required, the P side connected by the channel abnormality cannot be subjected to joint tripping, and thus, the operation with the fault is likely to be carried out for a moment, and skip-step tripping is caused. The case of a similar fault long jump command on the P side is the same as that on the N side. Obviously, the existing three-terminal differential has a dead angle of action for far jump, when the three-terminal differential has a channel fault on one side, although the differential protection still can correctly act after the host is automatically switched, the channel abnormal side cannot transmit a far jump command to the other two sides, and the fault cannot be timely removed. The invention is based on the improvement of the implementation scheme of a long jump when one communication fails.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a method for processing a far jump under the condition of an abnormal three-terminal differential channel, wherein when the channel is abnormal, a far jump command is forwarded through a host, so that the far jump commands between two hosts with abnormal channels can be mutually transmitted, and the rapid protection is realized; when the channel is normal, the original mode is still adopted to send information to the adjacent side, and the information is not forwarded, so that an information storm in a communication ring is avoided.

In order to achieve the purpose, the invention provides the following technical scheme:

the method for processing the long jump under the abnormal condition of the three-terminal differential channel comprises the following steps:

step 1, each device always monitors the state of each channel under normal conditions and transmits the channel state to all connected protection devices;

step 2, when one channel is abnormal, the host automatically switches to the host with normal channels on two sides;

step 3, the switched host forwards the received long jump command to the adjacent two-side devices, and simultaneously sends the long jump command of the host side to the two-side devices;

and 4, the device receiving the long jump command executes the long jump command according to the set conditions.

Further, in step 1, when all channels are normal, the host is determined by the identification code.

Further, in step 3, in the case of a channel abnormality, the host will forward as long as any device in the communication ring sends out a far-jump signal.

Compared with the prior art, the invention has the following advantages and beneficial effects:

by applying the method of the invention, when one channel has a fault, the remote jump command between two hosts with abnormal channels can be mutually transmitted by switching and forwarding the remote jump command through the hosts, thereby realizing rapid protection, and both differential protection and remote jump protection in a communication ring can be correctly executed without being influenced by the channel fault. The invention transmits the far jump command through the host, eliminates the problem that the far jump has dead zone under the condition that the three-terminal differential motion is abnormal in one channel, ensures that the far jump can also act quickly under the working condition, and improves the operation reliability of the site.

Drawings

FIG. 1 is a schematic diagram of three-terminal differential remote jump command transmission.

Fig. 2 is a schematic flow chart of a method for processing far jump under an abnormal condition of a three-terminal differential channel according to the present invention.

FIG. 3 is a schematic diagram of the improved three-terminal differential with one channel abnormal long jump command transmission.

Detailed Description

The technical solutions provided by the present invention will be described in detail below with reference to specific examples, and it should be understood that the following specific embodiments are only illustrative of the present invention and are not intended to limit the scope of the present invention.

The flow of the method for processing far jump under the abnormal condition of the three-terminal differential channel provided by the invention is shown in figure 2, and the method comprises the following steps:

(1) normally each device monitors the status of each channel and transmits the channel status to all connected protection devices, the host being dependent on the identification code.

(2) When one channel is abnormal, the host automatically switches to the host with normal channels on two sides, in this example, as shown in fig. 3, after the channel between N and P is abnormal, the host automatically switches to the M device; the host switching is performed on the premise that all communication states of all devices are known, if an abnormal host exists, the host is switched to the device with normal channels on both sides, and if all the channels are normal, the host is determined by the identification code.

(3) The host in this system will forward the received far-jump command and also send its own far-jump command to both sides, as shown in fig. 3, the M device will forward the far-jump command received from the P device to the N device, and at the same time, will also forward the far-jump command received from N to the P device. In this step, if there is a channel exception, the host will forward as long as any device in the communication ring sends out a far-jump signal.

(4) The device receiving the long jump command executes the long jump command according to the set condition.

The technical means disclosed in the invention scheme are not limited to the technical means disclosed in the above embodiments, but also include the technical scheme formed by any combination of the above technical features. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and such improvements and modifications are also considered to be within the scope of the present invention.