JP2001119852A - Protective relay method in loop system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid occurrence of a case where protection is impossible in different systems, which is caused by fixing a central unit to one side of O1 voltage or O2 voltage in breaker positions at both ends of a loop line, thereby performing the protective operation, in the central unit which serializes the loop system connected to each consumer via a loop line from a power source. SOLUTION: A central unit 10 performs protective operation (S1-S3), by taking in O1 voltage and O2 voltage of breakers MO1 and MO2 at both ends of a loop line, and selecting the voltage of the larger one between the zero-phase voltage V01 of the O1 voltage and the zero-phase voltage V02 of the O2 voltage. It includes selecting the voltage on the side, where a voltage at or higher than certain value between the zero-phase voltages V01 and V02 is generated and moreover selecting the O1 voltage preferentially, when the zero-phase voltages V01 and V02 are both at or higher than certain values, and others.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protective relay system for a ring system, and more particularly to a method for selecting an accident voltage used in a relay element.

[0002]

2. Description of the Related Art In a protection relay system for a ring system, a central device housing a relay is configured in two lines. FIG. 5 shows the system configuration. Central devices 1 and 2 that are a combination of central relay devices 1A and 2A and central communication devices 1B and 2B are provided at the power supply end positions of the first and second systems, and a relay unit and a transmission unit are provided at each customer position on the loop line. the terminal device 3 ₁ to 3 _N consisting provided,
These terminal devices 3 ₁ to 3 _N and the central communication device 1B, are connected with 2-system transmission line conventional system and loopback system between 2B.

In this configuration, current and voltage information of each customer and substation is transferred to a central relay device (central processing unit) via a transmission line, and is subjected to protection arithmetic processing. When the result of the protection operation in the central relay device is determined to be an accident, the result is transferred to the relay unit of each terminal device via the transmission line,
Trip the circuit breaker in the accident section.

The central unit 1 of the first system always uses the O1 voltage of the first system, and the central unit 2 of the second system always uses the O1 voltage of the circuit breaker MO2.
Performs a relay operation using two voltages. In the 1-system central unit 1, the output circuit breaker MO1 (or LS) on the O1 voltage side is "off", and the output circuit breaker MO2 (and L
When S) is "ON", switching to the O2 voltage is performed. The system 2 central unit 2 is connected to the output circuit breaker MO2 (or L
S) is "OFF" and the O1 voltage side feed-out circuit breaker MO1
(And LS) is "ON", the voltage is switched to the O1 voltage.

FIG. 6 shows a relay configuration of the central unit and the terminal unit, FIG. 7 shows a line protection relay sequence, and FIG. 8 shows a bus protection relay sequence. The central device 1 of the first system and the central device 2 of the second system each implement the illustrated relay sequence, and the terminal device trips the circuit breaker by the OR logic of the first system and the second system.

The element (main detection element) for switching the voltage acquired by the central unit and the terminal unit is indicated by □ 87G in the figure.
(Internal ground fault differential relay), □ 87BG (bus protection differential relay), □ 27S (insufficient voltage relay), □ 44SF (short-circuit distance relay), □ 67GF (ground fault direction relay). In addition, the numerical value in the square is assigned and indicated according to the number of terminals in the ring system.

[0007]

In the conventional two-series system, basically, the system 1 performs the operation of the □ 87G and □ 87BG relays with the O1 voltage and the O2 voltage with the system 2 and therefore, the system is connected to the loop line in the event of an accident. Even if a disconnection section occurs, the system can be protected by either system 1 or system 2 during operation in different systems, and each terminal device receives a cut-off signal from system 1 central device 1 and system 2 central device 2. OR trips the circuit breaker.

Here, when the central device is integrated into one line, 1
Since 27S, 44SF, and 67GF of the system are relays that detect whether there is an accident in the ring system from the circuit breaker side of the MO1, the voltage can be fixed to the O1 side voltage. Use voltage. In addition, 2 of 2
7S, 44SF, and 67GF are relays that detect whether there is an accident in the ring system from the circuit breaker side of MO2.
Voltage can be fixed, and O
Use two-sided current and voltage.

However, □ 87G and □ 87BG are
A case where one voltage is used and a case where O2 voltage is used are considered. In a normal loop system (all the breakers are “on”), the O1 voltage and the O2 voltage are the same, but when the circuit breaker and the bus circuit breaker in the ring system are “off”, the O1 voltage is changed depending on the location of the accident. There are cases where it should be used and cases where the O2 voltage should be used.

FIG. 9 shows a circuit breaker in the ring system (terminal 2 in the figure).
01CB) indicates an accident case in which the vehicle is in the “OFF” state. At this time, the bus CB is also “OFF” and the MO1 side and the MO2 side are different systems. When the 01 circuit breaker of the terminal 2 is “OFF”, F
For a ground fault that has occurred at one point, it is necessary to perform a relay operation using the voltage on the O1 side. On the other hand, for a ground fault occurring at the point F2, it is necessary to perform a relay operation using the voltage on the O2 side.

That is, if the voltage is not selected as described above, no zero-phase voltage is generated, so that it is not possible to detect a ground fault, and it is impossible to eliminate the fault.

Therefore, when the central device is integrated into one system, if the O1 voltage or the O2 voltage is fixed to the reference voltage by the system as in the conventional two-system configuration, there are cases where the accident cannot be eliminated due to the operation mode and the accident case. Conceivable. For example, if the O1 voltage is used during operation in a different system as shown in FIG. 9, protection at the time of an accident at point F2 cannot be performed.

[0013] An object of the present invention is to provide a protection relay system for a ring system which can protect the ring system by a centralized system that can be protected in most accident situations such as a single accident or a chasing accident. It is in.

[0014]

Means for Solving the Problems (First Invention) A central unit is provided in which a ring system connected from a power source to each customer via a ring is integrated into one line, and the central unit includes a bus line protection differential relay unit and A protection relay system having an internal ground fault differential relay means for detecting an accident of a ring line, wherein the central device captures O1 voltage and O2 voltage at breaker positions at both ends of the line, and
Select O1 voltage or O2 voltage larger of the first voltage of zero-phase voltage V ₀₁ and O2 voltage of zero-phase voltage V ₀₂ and performing protective operation by said relay means.

(Second Invention) A central device is provided in which a ring system connected from a power source to each customer via a ring is integrated into one line, and the central device includes a bus line protection differential relay means and an internal ground fault differential relay. a protective relay system has a means for detecting an accident of the ring line, the central apparatus takes the O1 voltage and O2 voltage circuit breaker position of the ring line ends, O1 zero-phase voltage V ₀₁ and O2 voltage of the voltage Of the zero-phase voltage _V02 of the above, the O1 voltage or the O2 voltage on the side that generates a certain value or more is selected, and when both the zero-phase voltages _V01 and _V02 are not less than a certain value, O
The present invention is characterized in that one voltage is preferentially selected and the protection operation by the relay means is performed.

(Third invention) A central device is provided in which a ring system connected from a power supply to each customer via a ring is integrated into one line, and the central device is a bus line protection differential relay means and an internal ground fault differential relay. a protective relay system has a means for detecting an accident of the ring line, the central apparatus takes the O1 voltage and O2 voltage circuit breaker position of the ring line ends, O1 zero-phase voltage V ₀₁ and O2 voltage of the voltage more than a predetermined value generates select O1 voltage or O2 voltage side are of the zero-phase voltage V _02, and the zero-phase voltage fast zero-phase voltage V ₀₁ and V ₀₂ together when more than a predetermined value is constant The O1 voltage or the O2 voltage on the side exceeding the value is selected, and when the zero-phase voltage simultaneously exceeds a certain value, the O1 voltage is preferentially selected and the protection operation by the relay means is performed. .

(Fourth invention) A central device is provided in which a ring system connected from a power source to each customer via a ring is grouped into one line, and the central device is a bus line protection differential relay means and an internal ground fault differential relay. A protection relay system for detecting an accident of a loop line having a means, wherein the central unit individually takes in the O1 voltage and the O2 voltage of the circuit breaker positions at both ends of the loop line into the two relay means, and performs a protection calculation. A relay is provided, and a protection output is obtained by a logical sum of outputs from the individual relays.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 shows an embodiment of the present invention and shows an example of the configuration of a ring system and a voltage selection sequence portion of a centralized central unit.

In the ring system having the terminals 1 to 3, the centralized unit 10 that has been grouped takes in the O1 voltage and the O2 voltage, and compares the magnitudes of the zero-phase voltages V ₀₁ and V ₀₂ (S1). , Use the larger voltage (S02,
S03).

In this selection method, when the normal ring system in which no accident occurs is maintained, the O1 voltage and the O2 voltage are the same, and therefore, the central unit 10 can use either voltage. Can be protected without problems.

Next, as shown in FIG. 1, for a single incident upon different systems operating in the F1 point accidents, O1 is the zero-phase voltage Vo ₁ is generated in the voltage, the O2 voltage zero-phase voltage Vo _{Since 2} does not occur, the central device 10 uses the O1 voltage, and the accident can be correctly removed.

In the F2 point accident, Vo ₂ is generated in the O2 voltage, contrary to the F1 point accident, while V2 is generated in the O1 voltage.
Since the o ₁ does not occur, will be using the O2 voltage, can correctly accident removed.

Next, in the case of a chasing accident from point F1 to point F2 during the operation of the different system, if "O1 voltage V ₀₁ ">"O2 voltage V ₀₂ ", the F1 point accident is removed. since Vo ₁ is eliminated, switches to Vo _2, it is possible to remove the F2 points.

Conversely, in the case of a chasing accident from point F2 to point F1 (the chasing time is within the timer of the mouth 87GTO), Vo ₂
> In Vo _1, detects the F2 points accident (3) 87G
After the relay operates, it returns once and detects the F1 point accident (2)
After the 87G relay operates and the F1 point accident is eliminated first, the F2
This will eliminate point accidents. In this case, although the removal of the F2 point accident is delayed, protection is possible.

(Second Embodiment) FIG. 2 shows an embodiment of the present invention, and shows only a voltage selection sequence part of a centralized central unit.

In this embodiment, the zero-phase voltage is generated at a certain value or more.
Select the generated voltage and keep the O1 voltage and O2 voltage constant
If the value is equal to or more than the value, the O1 voltage is given priority. That is, zero phase
Voltage V₀₁Is greater than the fixed value K (S11), the O1
The pressure is used (S12). V ₀₁Is less than the constant value K
Combined with V₀₂Is greater than the fixed value K (S13), the O2
The pressure is used (S14). Note that the constant value K is
The detection level (Vo cut voltage) is used.

In the present embodiment, a single accident can be protected normally as in the first embodiment. Also, in the case of a chasing accident at the time of operation in a different system, similarly to the first embodiment, when a chasing accident from point F1 to point F2 occurs and "O1 voltage V ₀₁ ">"O2 voltage V ₀₂ ", Can be protected normally. In F2 points → F1 point of chasing accident (chase time is within timer of mouth 87GTO), when the V _02> V _01, delayed the removal of F2 points accident.

(Third Embodiment) FIG. 3 shows an embodiment of the present invention, and shows only a voltage selection sequence portion of a centralized central unit.

In this embodiment, the zero-phase voltage is a constant value (V ₀
A voltage generated at least equal to (cut voltage) K is selected. When both the O1 voltage and the O2 voltage are equal to or more than the constant value K, the voltage at which the zero-phase voltage quickly exceeds the constant value is selected. That is, when the zero-phase voltage _V01 is equal to or higher than the fixed value K (S21), the O1 voltage is continuously used (S22). When V ₀₂ is above a predetermined value K and V ₀₁ is no longer less than the predetermined value K (S23), O2
Continue using the voltage (S24). Also, the O1 voltage and O2
When the voltage simultaneously exceeds the fixed value K, the O1 voltage is selected (S25).

In the present embodiment, a single accident can be protected normally as in the first embodiment. In addition, regarding the chasing accident during the operation of the different system, the chasing accident from the point F1 to the point F2, “O1 voltage V ₀₁ ”> “O2 voltage V
_{In the case of} " ₀₂ ", normal protection is possible as in the first and second embodiments. F2 point → F1 point chasing accident (Chase time is within the timer of mouth 87GTO), V
_{When 02} > _V01 , the F1 point accident removal is performed after the F2 point accident removal. Therefore, as in the first and second embodiments, the F2 point accident removal relay returns once after the operation, and further the F1 point accident removal. The operation delay that eliminates the F2 point accident after the operation is eliminated.

(Fourth Embodiment) In the present embodiment, FIG.
As shown in the figure, the centralized device in one line has a port 87G (1) and □ 87BG (1) relay using the O1 voltage, and □ 87G (2) and □ 878 using the O2 voltage.
G (2) Relays are individually mounted. And □ 87G
(1) and □ 87G (2) are OR (logical sum) outputs.
Also, □ 87BG (1) and □ 87BG (2) are ORed.

In the present embodiment, the first accident is
Normal protection is possible as in the third embodiment. In addition, when operating in a different system, (2) 8
Since the 7G (1) relay operates and the (3) 87G (2) operates for eliminating the F2 point accident, normal protection is possible. In the case of a chasing accident during the operation of a different system, F1
For point accidents, (2) 87G (1) relay operates and F
Regarding a two-point accident, (3) the 87G (2) relay operates, and protection can be performed without delay.

[0033]

As described above, according to the present invention, the O1 voltage and the O2 voltage at the circuit breaker position are appropriately selected to protect the ring system with the centralized unit that is integrated into one line.
Even in the case of a single accident and multiple accidents, a chasing accident, a different system operating, and a chasing accident straddling between different systems, it is possible to eliminate the accident with almost no operation delay.

[Brief description of the drawings]

FIG. 1 shows a ring system and a voltage selection sequence according to an embodiment of the present invention.

FIG. 2 is a voltage selection sequence according to another embodiment of the present invention.

FIG. 3 is a voltage selection sequence showing another embodiment of the present invention.

FIG. 4 shows □ 87G and □ 87 showing another embodiment of the present invention.
BG relay internal sequence.

FIG. 5 is a configuration example of a protection relay system in a ring system.

FIG. 6 is an example of the relay configuration of FIG. 5;

FIG. 7 is a line protection relay sequence of the protection relay device in FIG.

FIG. 8 is a bus protection relay sequence of the protection relay device in FIG. 5;

FIG. 9 is an example of an accident case in which the CB in the ring system is “OFF”.

[Explanation of symbols]

1A ... 1 based protective relay device 1B ... 1 based communication apparatus 2A ... 2 based protective relay device 2B ... 2 system of the communication apparatus 3 ₁ to 3 _N ... terminal device of

Claims (4)

[Claims] A central device is provided in which a ring system connected from a power supply to each customer via a ring is integrated into one line, and the central device has a busbar protection differential relay means and an internal ground fault differential relay means. A protection relay system for detecting an accident in the loop line, wherein the central device captures the O1 voltage and the O2 voltage at the breaker positions at both ends of the loop line, and obtains the zero-phase voltages _V01 and O2 of the O1 voltage.
Larger ring line system protective relay system which is characterized in that the selected protective operation by the relay means O1 voltage or O2 voltage of the zero-phase voltage V ₀₂ of the voltage. 2. A central unit having a series of ring systems connected from a power supply to each customer via a ring line is provided, and the central unit has a bus line protection differential relay unit and an internal ground fault differential relay unit. A protection relay system for detecting an accident in the loop line, wherein the central device captures the O1 voltage and the O2 voltage at the breaker positions at both ends of the loop line, and obtains the zero-phase voltages _V01 and O2 of the O1 voltage.
Select the O1 voltage or O2 voltage on the side of the zero-phase voltage _V02 which generates a voltage equal to or more than a certain value, and give priority to the O1 voltage when both the zero-phase voltages _V01 and _V02 are not less than a certain value. And a protection operation by the relay means is performed. 3. A central device is provided in which a ring system connected from a power supply to each customer via a ring is integrated into one line, and the central device has a bus-bar protection differential relay means and an internal ground fault differential relay means. A protection relay system for detecting an accident in the loop line, wherein the central device captures the O1 voltage and the O2 voltage at the breaker positions at both ends of the loop line, and obtains the zero-phase voltages _V01 and O2 of the O1 voltage.
The zero-phase voltage fast constant value select O1 voltage or O2 voltage above Occurring side, and when said zero-phase voltage V ₀₁ and V ₀₂ together above a certain value of the zero-phase voltage V ₀₂ of the voltage The O1 voltage or the O2 voltage on the side exceeding the predetermined value is selected, and when the zero-phase voltage simultaneously exceeds the predetermined value, the O1 voltage is preferentially selected and the protection operation by the relay means is performed. Protection relay system for the ring system. 4. A central device is provided in which a ring system connected from a power supply to each customer via a ring is integrated into one line, and the central device has a bus line protection differential relay unit and an internal ground fault differential relay unit. A protection relay system for detecting an accident of the ring line, wherein the central device is provided with individual relays for taking the O1 voltage and the O2 voltage at the circuit breaker positions at both ends of the ring line and performing a protection calculation on the both relay means, A protection relay system for a ring system, wherein a protection output is obtained by a logical sum of outputs from the individual relays.