JPH01264533A - Digital protection relay device - Google Patents

Abstract

PURPOSE:To delete a wasting time for altering a settling and to prevent the alteration of settling from erroneously occurring by setting in advance the settling of transmission lines, and automatically switching it to a settled value matched to the line to be protected. CONSTITUTION:Whether the arrays of '1', '0' of a settling pattern table are coincident with a pattern 1 or not is compared to detect a transmission line connected to a bus. If it is judged as a settling pattern 1, the pattern 1 settled in advance for a transmission line #1 is output by a settling memory, and the settling of a bus tie relay is altered to the pattern 1. If it is not the pattern 1, a settling pattern 2 is compared. Thereafter, the process is repeated until the coincident settling pattern is detected.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Field of Application) The present invention introduces the grid current of a busbar connection breaker unit that links dual main buses, and connects any of a plurality of power transmission lines with This invention relates to a digital protective relay device that protects power transmission lines.

(Prior Art) FIG. 3 is an example of an electric station having a double busbar and a plurality of power transmission lines. Power transmission lines #1 to #n are connected to disconnectors 1, Sl, and -A.

Bus-A via LSI-El-LSn-A and LSn-B, respectively.

It is connected to Bus-8. Also bus-A, B
The US-B is likely to be linked by the busbar additional twist breaker c[3-By.

Each power transmission line is connected to one of the busbars by opening and closing a disconnector. For example, when disconnector Lst-8 is closed and LSI-B is open, power transmission line #1 is connected to bus line Bus-A.

Figure 4 shows that at the electrical station in Figure 3, transmission lines #2 to #n are connected to bus Bus-A, and only transmission line #1 is connected to bus Bus-A.
-8 in an operational state.

In the figure, only the closed state of the disconnector is shown, and the open state is omitted. In Figures 3 and 4, the protective relay device RY1''RY,n of each transmission line introduces grid current through current transformers CTI to CTn installed for each transmission line,
In the event of an accident on each power transmission line, the circuit breakers CB-1 to CBn are tripped. However, if the current transformer, circuit breaker, or protective relay device of the power transmission line cannot be used for inspection or repair, and the power transmission line cannot be stopped, only one of the transmission lines to be protected can be turned off as shown in Figure 4. The protective relay device BTRY (hereinafter referred to as bus tie relay device) connects to the busbar and in the event of an accident, connects the busbar breaker CB-BT to the busbar breaker by introducing the grid current from the current transformer installed in the busbar breaker section. I need a way to remove it.

In other words, if the equipment or protective relay device installed for each transmission line cannot be used for some reason, and if the transmission line cannot be stopped in spite of this, only the transmission line can be disconnected from one bus and all other transmission lines. A method is used to continue power supply by connecting the electric wire to the other bus bar and protecting the corresponding power transmission line with a bus tie relay device.

In addition, RYI to RYn and BTRY mentioned above are protective relay devices R.
They are stored together as YT.

(Problem to be Solved by the Invention) A distance relay system having the R-X characteristic shown in FIG. 5 is usually used in a bus tie relay device. The 01.02 element in FIG. 5 is a reactance relay that detects the magnitude of the reactance portion of the power transmission line impedance.

The SU element detects the absolute value of the impedance of the power transmission line using a Mori relay.

Figure 6 shows protection using each element in Figure 5. FIG. 2 is a block diagram of a configuration example of a bus tie relay device.

The block diagram will be explained below. When the 01 element and the SU element operate together, the A N-'D circuit 1 is established and the O
A first stage function that issues a tripping command via R circuit 3, and 02
When the element and the SU element operate together, the AND circuit 2 is established and the second stage function of issuing a tripping command via the OR circuit 3 after the time limit operation circuit T2 is activated, and when the SU element operates and the time limit operation circuit T3 is executed after the time limit has expired. A third circuit that issues a tripping command via the OR circuit 3.
It consists of three types of tier functions. At this time, the time limit of the time limit operation circuit has a relationship of T2<13.

Fig. 7 is a diagram explaining the function of Fig. 6, where the own rotation interval is Ll,
Assuming that the adjacent section is L2, the far end is L3, and the vertical axis is the tripping time T, the structure is such that the closer it is to its own rotation, the faster it is tripped. At this time, the setting of each function is as follows: If the impedance between the own circuits is ZL = 100%, the first stage is set to ZL.
Generally, the value is set to about 80%, the second stage is set to about 150%, and the third stage is set to about 300%. However, the impedance ZL of the power transmission line to be protected is not constant and varies from transmission line to transmission line. Since the power transmission line to be protected by the bus tie relay device changes each time from #1 to #n, it is necessary to change the setting every time the target power transmission line changes. Conventionally, setting changes have been made by human personnel, which requires a lot of time each time and causes errors in setting changes. In recent years, with the advent of digital protection relay devices using microcomputers, improvements in the setting method have been desired.

' The present invention has been made to solve the above information, and provides a digital protective relay device that does not require manual setting each time, but can be switched automatically.

[Structure of the invention]

(Means for solving the problem) A digital protective relay that protects a power system consisting of multiple power transmission lines connected via a disconnector to one of the double main buses with which the busbar connection circuit breaker is linked. The first invention provides a device for detecting a power transmission line to be protected based on the open/closed states of disconnectors of a plurality of power transmission lines; The relay is provided with a relay that protects the power transmission line to be protected by inputting the amount of current flowing through the intake bus-bar connection breaker selected from among preset setting conditions. A second invention also provides a detection means for detecting a power transmission line to be protected based on the open/closed states of disconnectors of the plurality of power transmission lines; relay, and a busbar relay that takes the setting conditions of this relay and protects the transmission line by inputting the amount of current flowing to the busbar connection breaker when either of the relays for each transmission line cannot protect the transmission line to be protected. and.

(Function) In the first invention, settings suitable for each power transmission line are set in advance.
The setting value is stored in the setting memory section, and by selecting the transmission line to be protected based on the combination of the open and closed states of the disconnectors of each transmission line, the setting value of the transmission line to be protected is retrieved from the setting memory section and the setting value of the bus tie relay device is selected. It is designed so that it can be changed automatically.

In addition, in the second invention, a power transmission line to be protected is selected from a pattern of combinations of open and closed states of disconnectors of each power transmission line, and the setting value of the power transmission line to be protected is retrieved from a setting memory section by setting the power for each power transmission line. The set value of the bus tie relay device can be automatically changed to the set value of the power transmission line to be protected.

(Example) Examples will be described below with reference to the drawings.

FIG. 1 is an example for explaining the relationship between the setting pattern, the opening/closing state pattern table of the power line disconnectors, and the setting memory section. In the setting pattern table, the disconnectors of each power line are
“1” if connected to us-[3, bus Bus-
The case where it is not connected to B is defined as II OII. In the setting pattern table, setting pattern 1 is used in which only transmission line #1 is connected to bus BUS-B, and below, only transmission line #n is connected to bus 1.
The setting pattern n is connected to i+BIJs-B. This setting pattern matches the setting pattern in the setting memory section, and setting pattern 1 in the setting memory section roughly stores the setting suitable for power transmission line #1.

FIG. 2 is a flowchart showing the mathematical content of FIG. This flowchart will be explained below.

Sl detects the open/closed state of the disconnector of each power transmission line.

In S2, the power transmission line I1A (hereinafter referred to as bridging) connected to both bus lines Bus-A and Bus-B is detected, and when there is a power transmission line being bridged, the setting of the bus tie relay device is not changed. This is because if there is a transmission line in the bridge, the fault current will be shunted and normal protection will not be possible. In S3, it is detected that only one line is connected to bus-B. This is because when using a bus tie relay device, only one line of the power transmission line to be protected is connected to one bus bar for protection, so it is basically impossible to connect and use two or more lines. The present invention utilizes this type of operation. S4 detects the power transmission line connected to bus-B, and can be easily determined by comparing whether the 1.0 arrangement in the setting pattern table of FIG. 1 matches pattern 1. s5 is set in s4 putter -8
= If it is determined that the transmission line # is
1, and change the setting of the bus tie relay device to setting pattern 1. If the setting pattern is not 1, the process advances to s6 and a comparison of the setting pattern 2 is performed. The method is not limited to that shown in FIG. 2, but there is also a method of detecting which power transmission line is connected to the bus BUS-B and then directly calling the setting pattern. 86 matching settling patterns
The process is repeated until it is detected between ~Sll.

As explained above, according to the present invention, the power transmission line to be protected is detected from the open/closed state of the disconnector of each power transmission line by comparison with the setting pattern table, and the setting is automatically changed to the setting in the setting memory section, which is the setting in advance. I can do it.

In addition, the power transmission line to be protected is detected from the open/closed state of the disconnector of each power transmission line by comparison with the setting pattern table, and the setting pattern detected from the setting memory section that stores the setting of the target power transmission line is automatically activated as a bus tie relay. It can be imported.

〔Effect of the invention〕

According to the present invention, by setting the setting of each power transmission line in advance, the setting value is automatically switched to the one suitable for the transmission line to be protected, or the setting of the transmission line protection device of the target power transmission line is set by the bus tie relay. Since the settings are automatically imported, the time spent on setting changes, which conventionally had to be done manually, can be reduced and mistakes in setting changes can be prevented. This contributes to more efficient operation and improved reliability of the device.

[Brief explanation of the drawing]

Fig. 1 is a related diagram of a setting pattern diagram and a setting memory section that constitute the present invention, Fig. 2 is a flowchart of the present invention, Fig. 3 is an example of an electric station where the device is installed, and Fig. 4 is a diagram of the setting pattern of the present invention. An example of an electrical station in an operation mode for detailed explanation, Fig. 5 is an R-X characteristic diagram of a distance relay, Fig. 6 is a tripping block diagram, and Fig. 7 is a system example for explaining Fig. 6. It is. 81~Sll/program instructions, Bus-A, +3US-8 bus, #i-#n-power transmission line, Cl3-1-CBn, CB-BT-breaker,
LSI-A-LSn-A, LSI-B-LSn-B,
LS-BT-A, LS-BT-B-disconnector, RYI
~RYn...Protective relay device, BTR'Y...Bustie relay device, CTI-CTn
, CT-BT-current transformer, 0'l, 02... Reactance relay element, SU... Mori relay element, 1,2
...AND circuit, 3...OR circuit, Tl
, T2...Time-limited operation circuit, Agent Patent attorney Noriyuki Chika Ken Daishimaru

Claims (2)

[Claims] (1) In a digital protective relay device that protects a power system consisting of a plurality of power transmission lines connected via a disconnect switch to either of the dual main buses in which the busbar connections and disconnectors cooperate, the above-mentioned A detection means detects a power transmission line to be protected from the open/closed states of disconnectors of multiple power transmission lines, and a setting condition is selected from preset conditions for each power transmission line to be protected according to the output from this detection means. A digital protective relay device comprising: a relay that protects a power transmission line to be protected by inputting the amount of current flowing to the busbar connection or disconnector. (2) In a digital protective relay device that protects a power system consisting of a plurality of power transmission lines connected via a disconnector to either of the double main buses in which busbar connections and disconnectors cooperate, the above-mentioned A detection means for detecting a power transmission line to be protected from the open/closed states of disconnectors of a plurality of power transmission lines, a relay for each power transmission line that performs protection by inputting the current flowing through the transmission line or the disconnector, and A busbar relay that takes the setting conditions of this relay and protects the transmission line by inputting the amount of current flowing to the busbar contactor or disconnector when one of the relays for each electric wire cannot protect the transmission line to be protected. A digital protective relay device characterized by: