JP2013073782A - Breaker contact piece exhaustion amount management system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a breaker contact piece exhaustion amount management system capable of calculating exhaustion amount of a breaker efficiently at a low cost.SOLUTION: An oscilloscope is setup at a high-order electric power station, and relating to a distance relay for backup protection, trigger is executed by respective operation signals of a multistage relay in addition to a breaker trip signal. The oscilloscope includes a delay time table which stores a delay time that means time duration before recording of electric signal is stopped after detection of trigger, delay time setting means which sets a delay time that corresponds to a time zone in which the operation signal is outputted by referencing to the delay time table after detection of trigger, a stop timer which outputs a recording stop command based on the lapse of delay time, and electric signal recording means which records an electric signal by a memory circulation method until the record stop command is received from the stop timer. By taking the recorded data of the oscilloscope into a computer device, the contact piece exhaustion amount of breakers of the electric power stations at a high order and a low order are calculated.

Description

  The present invention relates to a circuit breaker contact consumption management system that efficiently collects operation signals and electrical data of protection relays installed in a power system and calculates the contact consumption of a circuit breaker contact.

  The circuit breaker contacts are consumed every time they are shut off, so they need to be replaced if they are shut off several times. Generally, when the cut-off current is large, the consumption amount tends to increase. The amount of wear is estimated using data such as the maximum short-circuit capacity for the current fiscal year, or a power oscilloscope (hereinafter simply referred to as an “oscilloscope”) is installed at each electric station, and the measured breaking current is also measured. Or to calculate.

  The grasping of the breaking current is measured by an oscilloscope as described in Patent Document 1, and using this measurement data, the consumption amount (wear rate) is calculated using an arithmetic expression as described in Patent Document 2. We are grasping.

Japanese Patent Laid-Open No. 9-166651 JP 2007-149458 A

  However, estimating from the maximum short-circuit capacity of the current year has a large error, and it is necessary to measure three phases for calculating the breaking current. However, the number of inputs to the oscilloscope is limited and there are many lines of electricity. On the other hand, there are cases where only two phases of the line are inputted or only the zero phase is inputted, so that it is impossible to accurately grasp the short-circuit current, and therefore it is impossible to accurately grasp the amount of contact consumption. Moreover, in order to grasp correctly, it is necessary to install an oscilloscope device in each electric station, and it becomes expensive.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a contactor consumption amount management system for a circuit breaker that can efficiently calculate the consumption amount of the circuit breaker at low cost. To do.

  To achieve the above object, the contact consumption control system for a circuit breaker according to the present invention records an electrical signal including a voltage / current of a power transmission system and uses a trip signal of a distance relay as a trigger to set a preset trigger. An oscilloscope device that records and stops an electrical signal between a pre-occurrence time (hereinafter referred to as a gradual time) and a predetermined time after the occurrence of a trigger, a transmission device that transmits recording data of the oscilloscope device, and a communication network from the transmission device A circuit breaker contact consumption management system comprising: a computer device that receives the recording data of the oscilloscope sent via the computer and calculates the contact consumption of the circuit breaker based on the recorded data The distance relay includes an electric station where the distance relay and the oscilloscope device are installed in a power transmission system based on an electric signal, and a subordinate electric station. Detecting an abnormality for each section and outputting an operation signal and outputting a trip signal after a predetermined time has elapsed for each section after the operation signal is output, and the oscilloscope performs recording measurement at each section. And a delay time table for storing an electrical signal between a gradual time and a predetermined time after the trigger detection and a delay time that is a time until the stop after the trigger detection, and a delay time table after the trigger detection A delay time corresponding to the section in which the operation signal is output is set by reference, a stop timer that outputs a recording stop command when the delay time elapses, and an electric signal is circulated in the memory until a recording stop command is received from the stop timer And an electrical signal recording means for recording in a formula, wherein the stop timer detects the trigger again after the trigger time is detected and before the elapse of the delay time. The computer device restarts by setting a time corresponding to the category of the operation signal that caused the timer, and the computer device receives data recorded by the oscilloscope sent from the transmission device; The circuit breaker installed at each electric station of the power transmission system, the operation circuit breaker determination means for determining the operated circuit breaker, and the record data for each circuit breaker determined by the operation circuit breaker determination means And a contact consumption amount calculating means for calculating the contact wear amount of the circuit breaker.

  In the present invention, an oscilloscope device is installed at a higher power station, and a trigger is applied by each operation signal of the multistage relay (a signal before the time element input) in addition to the circuit breaker trip signal. The recorded data of the oscilloscope device is taken into a computer device, and the contact consumption of the circuit breakers at the upper and lower electric stations is calculated. This makes it possible to manage the contact consumption of the circuit breaker at the lower electric station by using the recording data of the oscilloscope installed at the upper electric station.

  The delay time stored in the delay time table is preferably larger than the set value of the distance relay time relay in the section.

  The operation circuit breaker determination means of the computer device calculates the contact consumption amount of the circuit breaker for each of the two or more sections when the distance relay operation signal is output for two or more sections. And Thereby, the maintenance management of a circuit breaker becomes more reliable.

  Further, the operation breaker determining means of the contactor consumption control system for a circuit breaker according to the present invention is a section in which the operation section of the distance relay includes the other end, and the magnitude of the breaking current calculated from the recorded data of the oscilloscope device Is less than a predetermined value, it is determined that it is a busbar accident at the other end.

  Further, the delay time setting means of the contactor consumption amount management system for a circuit breaker according to the present invention includes a value obtained by adding a constant value to a set value of the time relay for the distance relay input via the digital input means. It is set as a delay time corresponding to the section of the distance relay in the time table.

  In the present invention, by setting the setting value of the time relay for the distance relay and the setting of the delay time of the oscilloscope device (time until the recording stop after the trigger), the circuit breaker is operated at the lower electric station. However, it is possible to reliably collect electrical data necessary for calculating the contact consumption of the circuit breaker.

  According to the present invention, since the consumption amount of the contact of the circuit breaker of the lower electric station is calculated by the oscilloscope device installed in the upper electric station, the number of installation of the oscilloscope apparatus can be reduced, and the consumption of the contactor can be reduced at a low cost. The amount can be managed. Further, it is possible to efficiently manage the amount of consumption of the contact by collecting the electrical data necessary for the calculation of the amount of consumption from the upper power station automatically using the communication network.

1 is a system configuration diagram of a power transmission system including a contact consumption control system for a circuit breaker according to an embodiment of the present invention. It is a block diagram of the protection relay 13 and the oscilloscope device 2 of FIG. It is the protective relay 13 of FIG. 1, Comprising: It is explanatory drawing of the setting state of a distance relay. 3 is a flowchart showing a procedure of a recording stop process of the oscilloscope 2 of FIG. It is a functional block diagram of the computer apparatus 4 of FIG. It is explanatory drawing of the time cooperation of the distance relay of a power transmission end, and the overcurrent relay of the other party end (the 1). It is explanatory drawing of the time cooperation of the distance relay of a power transmission end, and the overcurrent relay of the other party end (the 2). It is a data block diagram of the contactor data file 43 of FIG. It is a systematic diagram for demonstrating the interruption current calculation process by the other Example of this invention (accident example 1). It is a systematic diagram for demonstrating the interruption current calculation process by the other Example of this invention (accident example 2). It is a systematic diagram for demonstrating the interruption current calculation process by the other Example of this invention (accident example 3). It is a systematic diagram for demonstrating the interruption current calculation process by the other Example of this invention (accident example 4).

  Hereinafter, a contactor consumption management system for a circuit breaker according to an embodiment of the present invention will be described with reference to the drawings. The following embodiment is a preferred specific example of the contactor consumption management system for a circuit breaker according to the present invention, and may have various technically preferred limitations, but the technical scope of the present invention. Unless otherwise specified, the present invention is not limited to these embodiments. In addition, the constituent elements in the embodiments shown below can be appropriately replaced with existing constituent elements and the like, and various variations including combinations with other existing constituent elements are possible. Therefore, the description of the embodiment described below does not limit the contents of the invention described in the claims.

  FIG. 1 is an explanatory diagram of a power system to which the contactor consumption management system for a circuit breaker according to the first embodiment is applied. The circuit breaker contact consumption management system 1 includes an oscilloscope device 2, a transmission device 3 that transmits data stored in the oscilloscope device 2, and data transmitted from the oscilloscope device 2 via the communication network 5. And the computer device 4 that calculates the contact consumption amount of the circuit breaker.

  The oscilloscope device 2 is provided in the upper power station 10 of the power transmission source among power generation / substations (hereinafter referred to as “electric station”) connected by the power transmission line 15. The upper electrical station 10 inputs the electrical data collected through the PT and CT electrical data collecting means 12 to the protective relay 13, and the protective relay 13 detects a system fault based on the inputted electrical data. Then, a trip signal is output to the circuit breaker 11 to trip the circuit breaker 11.

  Although not shown, the lower electrical station 20 also includes a protective relay and a circuit breaker that operate based on the electrical data collected through the electrical data collection unit. In addition, a conventional technique can be used for the protective relay, the circuit breaker, and the electrical data collection means provided in each electric station.

  In general, the relay system includes a pilot relay system, a line selection relay system, a distance relay system, and a ground fault direction / ground fault overvoltage system. However, as the data recording conditions of the oscilloscope according to the present embodiment, the following operating conditions are used. Is used.

  First, the operating conditions of a distance relay with back-end protection are used for a short circuit and a ground fault in a direct grounding system. As for the resistance grounding system, a short-circuit is used for the distance relay, and a ground fault is used for the ground fault direction and ground fault overvoltage (if there is no ground fault direction, only the ground fault overvoltage is used).

  The reason for this is that the pilot relay communicates failure information between its own end and the other end, and when it becomes unable to communicate, it will not operate, and the line selection relay can be used in a state where two lines are used together. This is because it does not operate in the (CB) off state. In addition, pilot system and line selection are adopted as main protection and differ depending on the line, but distance relay is adopted as main protection and set as back-up protection, so it is highly versatile and can analyze accidents on more lines Because it becomes.

  As described above, the distance relay as a protection for the transmission line is an impedance type for short circuit, and the ground fault differs depending on the grounding method, but the section can be identified by using any type of relay. it can. As shown in FIG. 3, the distance relay generally has three fault point detection sections of 1, 2, and 3 stages, and usually the first stage is a section (section 1) around 80% of the impedance of the transmission line to be protected. ), The second stage is set to protect 120% or more section (section 2), and the third stage is set to protect 250% or more section (section 3). In other words, the second stage and the third stage also protect the transmission line between the opposite electric stations and beyond the transmission line between the opposing electric stations.

  Normally, in an accident at the partner electrical station (lower electrical station), the premises protection relay of the partner electrical station operates in advance to shut off the counterpart circuit breaker, and the transmission line breaker at the power transmission end (upper power station) operates. do not do. This is because a timer is provided in the trip circuit of the backup protection relay, and a trip signal is output after the timer expires.

  However, the protection relay has been operating since the occurrence of an accident, although no trip signal is output. The present invention is characterized in that electrical data such as voltage and current is stored by the oscilloscope device using the operation signal of the protection relay.

  For example, in the short-circuit distance relay, as shown in FIG. 2, the outputs of the short-circuit distance relays (44S) 31a to 31c set for each section (this output is referred to as “operation signal”) are used for each short-circuit distance relay. Inputs to the time relays (44ST) 32a to 32c, and outputs of these time relays 32a to 32c are input to the OR circuit 33, and a trip signal for the circuit breaker is output under the OR condition of each output. Normally, this trip signal is used as a trigger for the oscilloscope 2, but in this embodiment, an operation signal for a distant section (sections 2 and 3) including the lower electrical station is also passed to the oscilloscope 2 to perform these operations. The signal is also used as a trigger for the oscilloscope 2. It is sufficient to use at least the operation signals in the sections 2 and 3 as a trigger, but the operation signal in the section 1 may be included.

(Configuration of oscilloscope)
The configuration of the oscilloscope 2 according to the present embodiment is shown in FIG.
In this figure, the oscilloscope 2 always measures, stores for a fixed time, starts recording from the progressive time set when the trigger is generated, and outputs a recording stop command when the set delay time elapses. , A delay time table 24 for storing each interval and a delay time that is a time until recording of an electric signal is stopped after detecting a trigger due to an abnormality in the interval, and a delay time table 24 after detecting the trigger. The delay time setting means 25 for setting the delay time corresponding to the section in which the operation signal is output with reference to the stop timer 23, and the electric signal recording for recording the electric signal in a memory circulation manner until the recording stop command is received from the stop timer 23 Means 22, digital input (DI) means 26 for inputting and recording each signal that causes the trigger (hereinafter referred to as “trigger type”), voltage / voltage Analog input (AI) means 27 for inputting an electrical signal, such as a flow, and includes an A / D converter 28 for converting the analog value into a digital value.

  Further, the section of the protective relay 13 is set as shown in FIG. 3, and the delay time of each section stored in the delay time table in this case is the set value + c of the time relay of that section. . The delay time for the trip signal is also the delay time c. Here, c is a positive value set in advance. For example, when the time relay 32b for the second stage distance relay is set to B (seconds), the delay time of the section 2 of the delay time table 24 is B + c (seconds). Note that c may be a different value depending on the trigger type.

Next, the recording stop process of the oscilloscope 2 will be described with reference to FIG.
When a trigger signal is output from the OR circuit 29b (S101), the delay time setting means 25 reads the trigger type (which section is the operation signal or trip signal) from the DI means 26 (S102), and the trigger The delay time corresponding to the type is read from the delay time table 24, set in the stop timer 23, and the stop timer 23 is started (S103). As a result, the stop timer 23 is decremented from the delay time value set as the initial value, and the timer value is zero, that is, after the set delay time has elapsed ("YES" in S104), the electric signal recording means 22 is Output a recording stop command. The electric signal recording means 22 converts the inputted electric signal into a digital signal by the AI means 27 and the A / D conversion means 28 when the power is turned on, and always records it in a memory circulation format. When the recording stop command is received, the recording is stopped (S105).

  It should be noted that the waveform of the electric signal, the signal input via the DI means 26 and the generation time of the trigger signal are timed by the radio clock 21 and recorded in the electric signal recording means 22.

  If a further trigger signal is generated while the delay time is elapsed by the stop timer 23 (“NO” in S104, “YES” in S106), the delay time setting means 25 delays the delay time corresponding to the trigger type. The extracted delay time is extracted from the time table 24 (S107), and the extracted delay time is compared with the current stop timer value (that is, the remaining time until the stop). Is set in the stop timer 23 and activated (S110). Thereby, even when a trigger occurs due to a plurality of factors, it is possible to record an electrical signal for a time required for the factors. Although not described in the flowchart of FIG. 4, when a trigger is generated simultaneously due to a plurality of factors, it is preferable to use the larger delay time corresponding to the factors.

  As described above, the trigger type and trigger time are recorded, and the recording time after the trigger is set longer than the time constant of the time relay (timer) corresponding to each operation signal. Even in a local accident, the interruption current can be grasped from the recorded data of the oscilloscope device of the power transmission end protection relay.

(Configuration of computer device)
FIG. 5 is a functional block diagram of the computer apparatus 4.
The computer device 4 is connected to a communication network, and receives a data transmission unit 60 that receives data transmitted from the transmission device 3, and a calculation unit 50 that performs processing for calculating the contact consumption of the circuit breaker based on the received data. And a storage unit 40 for storing data.

  In addition, the calculation unit 50 includes a data receiving unit 51 that receives data transmitted from the transmission device 3, an operation circuit breaker determining unit 52 that determines an operating circuit breaker based on the received data, and the oscilloscope 2. Breaking current calculating means 53 for calculating the breaking current based on the electrical data collected in step (b), and contact consumption amount calculating means 54 for calculating the amount of contact consumption of the breaker from the breaking current for each activated breaker. And.

Next, the operation of the computer device 4 will be described.
When the data receiving unit 51 receives the recording data of the oscilloscope device 2 sent from the transmission device 3 via the transmission unit 60, the data reception unit 51 stores it in the oscilloscope data file 41 of the storage unit 40.

(Operation breaker judgment processing)
Next, the operation breaker determining means 52 determines whether or not the own line CB has tripped when the reception of the data receiving means 51 is completed or is activated by the activation request from the input unit 61. It is determined whether an operation signal of three stages or only three stages has been generated. First, after the trigger, there is a two-stage operation, and if the accident current has been resolved within the two-stage timer + device operation time, it is determined that the circuit breaker after the counterpart end has operated within the two-stage section. If there is no 2-stage operation signal and a 3-stage operation signal is generated and the accident current has been resolved within the 3-stage timer + device operation time, it is determined that the breaker in the 3-stage section has been activated. To do.

  In addition, since the operation state of the circuit breakers other than the oscilloscope installation end is confirmed by the operator after the accident, information on the operated circuit breaker may be input via the input unit 61.

(Operation breaker judgment processing from oscilloscope data)
The operation breaker can be determined from the oscilloscope data by using a conventional accident point locating technique such as JP-A-2000-227453. Hereinafter, the determination procedure of the operation breaker determination means 52 will be described.

  First, the fault point is determined by the fault current, fault point location (impedance calculation), and fault duration based on the oscilloscope data at the power transmission end.

  FIG. 6 is a diagram showing the time cooperation of the distance relay at the power transmission end, the overcurrent relay (OC-A) on the counterpart power receiving side, and the overcurrent relay (OC-B) on the counterpart power transmission side. In the time-dependent coordination of relays as shown in FIG. 6, when an accident occurs at point x, the impedance (% Z) at point a is calculated from the oscilloscope data at the power transmission end by fault location.

  Further, from the oscilloscope data at the power transmission end, for example, the failure continuation time can be determined by the time during which the voltage is not more than a predetermined value. The operation time b of the relay can be calculated by subtracting the operation time of the auxiliary relay (not shown) and the circuit breaker that are passed after the trip signal is output from the failure duration time.

  The fault current of the premises accident is calculated using the fault current of the oscilloscope data at the transmission end, and the relay operating time can be determined from this fault current and the relay set value. The relay that has been operated is identified by comparing the operation time of the relay due to the failure current with the operation time b obtained from the failure continuation. As a result, it is possible to estimate which circuit breaker has shut off even in a premises accident.

  Note that if OC-B is operating and tripping with timed coordination in FIG. 6, the failure duration should be shorter than b. However, if the failure continuation time from the oscilloscope data is b, it is not OC-B, and it can be determined that the blockage is at OC-A.

  In addition, when an accident occurs at point y as shown in FIG. 7, both OC-A and OC-B will trip and trip, but the fault point will be a breaker at the lower part but cut off the breaking current. Since it is not possible to specify either, it is assumed that both cut off the same current.

(Contact consumption calculation processing)
Since the amount of contact consumption is determined by the magnitude of the breaking current, it is only necessary to know the current when breaking.
Since it is a transmission line protection relay, the cutoff current of the own line transmission line accident can be grasped by the condition of own line relay operation + own line CB operation.

  In a premises accident at the other end (power receiving side power station), the transmission line relay at the other end does not operate, so there is no relay operation even if the CB operates at the time of the bus or Tr primary side accident. Current is not memorized.

However, at the power transmission end (power supply side), the power transmission line relay operates and the oscilloscope device 2 stores data at the time of the accident, and the oscilloscope data can be used to grasp the interruption current of the premises accident.
Note that the current data of the contact consumption is the breaking current of the circuit breaker, that is, the current immediately before breaking.

When the operation circuit breaker determination means 52 determines the operated circuit breaker, the operation circuit breaker determination means 52 increments the number of operation of the circuit breaker in the contact data file shown in FIG. Next, the contact consumption amount calculating means 54 calculates a cutoff current from the oscilloscope data and stores it in the contact data file 43.
Then, the consumption amount is calculated by the following equation using the maximum current as the cutoff current. The amount of consumption is calculated according to conventional techniques. (For example, refer to JP 2007-149458 A)
In addition, you may make it manage as a relative amount showing consumption amount as follows.

When V is a consumption amount, I is a cut-off current, t is an arc time, and α and β are coefficients determined by the contact material, the consumption amount V is expressed by the following equation.
V = α · I ^β · t

It should be noted that α and t are constants, and a relative amount A representing the amount of consumption can be obtained from the following equation from the relational expression between the amount of consumption V and the interruption current when the circuit is interrupted n times.
A = V / (α · t) = I ^β · n

The consumption amount of the circuit breaker contact may be managed by the relative amount A representing the consumption amount.
FIG. 8 shows an example of a contactor data file. It is a table when the rated breaking current is 31.5 kA, the rated breaking current is defined as 10 times, and the constant β that is a manufacturer setting value is 1.2. In this table, the cut-off current is obtained from the record data of the oscilloscope 2, but when there is no record data, the maximum value calculated in the corresponding year may be used.

(Cutting current calculation processing according to another embodiment)
Next, as another embodiment, a determination process in the case of two parallel lines according to the following example will be described. It is assumed that the fault location described in this section is all calculated from oscilloscope data. These determination rules may be defined and stored in the determination rule file 42 for each system configuration.

(Accident example 1)
In the system shown in FIG. 9, when an accident occurs on the AB line 1L, the line relays A, B, and C change and the circuit breakers A-1, B-1, and C-1 occur at any point of the accident. Is operated and shuts off, the breaking current of each breaker is calculated from the oscilloscope data by calculating the C variable bypass current I3 by the following equation.
I3 = {I2 · (Z2 + Z5 + Z4) −I1 · Z1} / (Z3 + Z4 + Z5)

  Here, Z1 is the impedance from the A change of the AB line 1L to the C change point, Z2 is the impedance from the A change of the AB line 2L to the C change point, and Z3 is the accident point from the C change point of the AB line 1L. , Z4 is the impedance from the accident point of AB line 1L to B change, Z5 is the impedance from the accident point of AB line 2L to B change, Z6 is the impedance from C change branch point to C change of AB line 1L , Z7 is the impedance from the C turning point of the AB line 2L to the C turning point.

  The cut-off current I1 of the A change A-1 is the current of 1L oscillodata, the cut-off current of the B change B-1 is the value obtained by subtracting I3 from the current I2 of the A change 2L oscillodata (I2-I3), and the C change C- The cut-off current of 1 is I3.

(Accident example 2)
When a B-bus fault occurs in the system shown in FIG. 10, the A-change becomes the power supply terminal and both A-change AB lines 1L and 2L operate, but normally the breaker B-1, B-2 is shut off in advance, and the A and C breakers do not operate.

  Normally, there is almost no difference in line impedance between the AB lines 1L and 2L, and there is almost no difference in impedance between the C variable branch lines, so that almost no detour current flows through the C change and the C variable line relay does not operate.

  Without the C variable line relay operation, the current of the A-modified AB line 1L oscilloscope data becomes the breaking current of the B-1 circuit breaker, and the current of the A-modified AB line 2L oscilloscope data becomes the breaking current of the B-2 circuit breaker.

  If there is a difference in the impedance of the AB lines 1L and 2L and there is a current that bypasses the C change, the C change bypass current I3 is obtained from the line impedance at the time of the accident and the A change oscilloscope data, and B changes B-1 and B-2. Find the breaking current.

When I3 is in the direction from AB line 1L to AB line 2L, I3 is calculated by the following equation.
I3 = (I2 · Z2−I1 · Z1) / (Z5 + Z6)
At this time, the breaking current of the breaker B-1 is I1-I3, and the breaking current of the breaker B-2 is I2 + I3.

When I3 is in the direction from AB line 2L to AB line 1L, I3 is calculated by the following equation.
I3 = (I1 · Z1−I2 · Z2) / (Z5 + Z6)
At this time, the breaking current of the breaker B-1 is I1 + I3, and the breaking current of the breaker B-2 is (I2-I3).

(Accident example 3)
In the system shown in FIG. 11 (a), when a B change bus accident occurs, the A change and the C departure are the power supply terminals, and the A change AB lines 1L and 2L are equipped with the oscilloscope and there is data, but the C departure is the oscilloscope. Not. In this case, the breaking current of the circuit breaker B-2 can be estimated as follows.

In FIG. 11 (b), the impedance of the AB line 1L is Z1, the impedance from the A change of the AB line 2L to the C branch is Z2, the impedance from the C branch of the AB line 2L to the B change is Z3, and the AB line 1L When the current is I1, the current of the AB line 2L is I2, and the current from the C source is I3, the impedances Z1, Z2, and Z3 are known by the line impedance, and the currents I1 and I2 are known by the line relay operation. If the current I3 is understood, the breaking current of the breaker B-2 is obtained. The current I3 can be calculated by the following formula.
I3 = {I1 · Z1−I2 · (Z2 + Z3)} / Z3
The current I1 is the breaking current of the breaker B-1, and the current I2 + I3 is the breaking current of the breaker B-2.

  In the case of an accident in the B-transformation, the impedance from the A-transformation is equal to the line impedance except for an accident in the transformer. However, as shown in FIG. 11 (c), when a fault current I2 flows from the C source, the A-variable relay has a further apparent increase in impedance due to the shunt effect, and is determined to be a distant accident. If the current I2 is obtained from the impedance that is apparently increased by the shunt effect, the sum of the current I1 and the current I2 becomes the breaking current of the breaker B-2.

That is, assuming that ZA is the impedance that the A-variable relay sees, the equation for the shunt effect is as follows.
ZA = Z2 + Z3 · {(I1 + I2) / I1}
∴I2 = {ZA- (Z2 + Z3)} · I1 / Z3

  The current I1 is not required to be calculated because it is known from the A-transform transmission line oscilloscope data, and the current I1 + I2 is the breaking current of the circuit breaker B-2.

  Further, in the accident between the C branch and the B change, the impedance up to the accident point becomes unknown due to the shunt effect while the C generator is generating power. If the C generator is in-house, the reactance of the generator can be grasped, and the impedance from the C departure to the branch can also be grasped. If the impedance of the power source behind the A change is known, the impedance that is the same as the fault current flowing from the A change can be obtained, and the fault current from the fault point and the C source can be obtained.

  The A-change voltage at the time of the accident is determined by the impedance at the accident point and the line impedance from the accident point to the A-change. If there is a large generator behind the A change, there is also an impedance from this generator and the generator to the A change, and these are called back power supplies, but the back power supply is a healthy voltage before the accident occurs and the fault current flows to the A change. The A variable voltage becomes lower due to the voltage drop.

Now, assuming that the voltage immediately before the accident is VB, the voltage at the time of accident is VΦS, the impedance viewed by the A-variable relay is ZA, and the A-variable power supply impedance is ZGA, the A-variable power supply impedance ZGA is calculated by the following equation. be able to.
ZGA = (VB / VΦS) · ZA-ZA

  Once this A-variable power supply impedance is known, all the impedances up to the branch are known, and after that, an impedance that is the same as the fault current that has flowed into the A-change at the time of the accident after the branch may be obtained.

  However, if the impedance at the fault point is large, the exact position on the track becomes unclear, so the fault current from the C source obtained by calculation is used to correct the shunt effect of the impedance ZA and correct the position of the fault point. .

・ Understanding the breaking current of the C circuit breaker: For the accident on the B change side from the C branch, calculate the fault current using the above method. Since there is no shunting effect on the A change side from the C departure branch, the impedance from the C departure to the fault point is obtained from the orientation distance from the A change, and the fault current from the C departure is obtained.

  In the case of the C departure branch line, it cannot be determined from the A change whether the B change side or the C branch line. In such a case, if a lightning is occurring, a lightning monitoring device is used to determine which point is the accident point.

  In small and medium-sized hydropower plants, the fault current is small and the power line breaker is cut off by shutting down all after the generator parallel breaker is cut off first by preventing single operation after turning off the A-transformed transmission line relay rather than the operation of the short circuit relay. At this time, the power line breaker is shut off with no load, so it is better to check the state change record.

  In addition, the interruption current at the time of a power line accident is often much smaller than the rating, and in this case, there is often no influence on grasping the amount of contact consumption even if the interruption of an external accident is not considered. The power line breaker of can be simplified to manage only the current of the premises accident.

(Accident example 4)
In the system shown in FIG. 12, when a B-transformer primary accident occurs, the A-transformation becomes the power supply terminal and both A-transform AB lines 1 and 2L operate, but the normal B-transformer protection OC relay As a result, the breaker B-3 is cut off in advance, and the breakers A and C do not operate.

  At this time, the sum of the current of the A-modified AB line 1L relay and the current of the A-modified AB line 2L relay becomes the breaking current of the circuit breaker B-3.

(Internal accident judgment)
In relays for electric premises, there are many infinite periods of time, and in the event of a short-circuit ground fault, if the fault point resistance is large, the fault current does not flow sufficiently, so the operation may slow down and the power transmission end may trip.

  In the case of one-line branching of two parallel transmission lines as shown in FIG. 11, it is difficult to distinguish between an accident on a premises or a branch line because the accident point is located near the branch even in an electric premises accident. For this reason, it is determined from the accident data at the power transmission end whether or not a sufficient operating current has flowed at the time of the campus accident.

  That is, when the breaking current is equal to or greater than a predetermined value and the power transmission end is tripped, it is determined that there is no on-site accident. If the cut-off current is less than a certain value and there is no transmission end trip, it is determined that there is a local accident. Also, if the breaking current is less than a certain value and the power transmission end trip occurs, it is determined that there is a possibility of a local accident.

As described above, according to the present embodiment, the consumption amount of the contact of the circuit breaker of the lower electric station is calculated based on the data of the oscilloscope apparatus installed in the upper electric station. The consumption of the contact can be managed at a cost. Further, it is possible to efficiently manage the amount of consumption of the contact by collecting the electrical data necessary for the calculation of the amount of consumption from the upper power station automatically using the communication network.
Further, instead of the oscilloscope, it is also possible to collect and utilize data by using a transmission line relay instead of the oscilloscope. If it does so, even if there is no oscilloscope device, the consumption of the contactor in the same level can be managed.

DESCRIPTION OF SYMBOLS 1 Contactor consumption management system of circuit breaker 2 Oscilloscope 3 Transmission apparatus 4 Computer apparatus 5 Communication network 10 Higher electric station 11 Circuit breaker 12 Electric data collection means 13 Protection relay 14 Overcurrent relay (OC relay)
15 Transmission line 20 Lower electrical station 21 Radio clock 22 Electrical signal recording means 23 Stop timer 24 Delay time table 25 Delay time setting means 26 DI means 27 AI means 28 A / D conversion means 29a, 29b OR circuits 31a, 31b, 31c Distance Relay 32a, 32b, 32c Timed relay (timer)
33 OR circuit 40 Storage unit 41 Oscillo data file 42 Judgment rule file 43 Contact data file 50 Calculation unit 51 Data reception unit 52 Operation breaker determination unit 53 Breaking current calculation unit 54 Contact consumption amount calculation unit 60 Transmission unit 61 Input unit

Claims (5)

Record electrical signals including the voltage and current of the power transmission system, and use the trip signal of the distance relay as a trigger, and the electrical signal between the preset trigger occurrence time (hereinafter referred to as progressive time) and after a certain time has elapsed since the trigger occurrence An oscilloscope device that records and stops recording, a transmission device that transmits recording data of the oscilloscope device, receives the recording data of the oscilloscope device sent from the transmission device via a communication network, and also stores the recorded data A circuit breaker contact consumption management system comprising: a computer device for calculating a contact consumption of the circuit breaker;
The distance relay detects an abnormality and outputs an operation signal for each predetermined section including the distance relay in the power transmission system, the electric station where the oscilloscope is installed, and the lower electric station based on the electric signal. A trip signal is output after a predetermined time has elapsed for each section after the operation signal is output,
The oscilloscope performs recording measurement at all times, and delays each of the intervals and a delay time, which is a time from when the trigger signal is detected to when the electrical signal is recorded from the progressive time to a certain time after the trigger is detected and stopped. A stop timer that sets a delay time corresponding to a section in which an operation signal is output with reference to the delay time table after detecting the trigger, and outputs a recording stop command when the delay time elapses, and the stop timer An electrical signal recording means for recording an electrical signal in a memory circulation manner until a recording stop command is received from the memory, and the stop timer detects the trigger again after the trigger time has elapsed, before the delay time elapses. Set the timer to the time corresponding to the category of the operation signal that caused the trigger, and restart.
The computer device includes a data receiving means for receiving data recorded by the oscilloscope sent from the transmission device, and a circuit breaker installed at each electric station of the power transmission system, An operation circuit breaker determining means for determining, and a contact consumption amount calculating means for calculating a contact wear amount of the circuit breaker using the recording data for each circuit breaker determined by the operation circuit breaker determining means. A circuit breaker contact consumption control system comprising a circuit breaker.   2. The contactor consumption management system for a circuit breaker according to claim 1, wherein a delay time stored in the delay time table is larger than a set value of a distance relay time relay in a section.   When the operation signal of the distance relay is output for two or more sections, the operation breaker determination means of the computer device calculates the contact consumption of the circuit breaker for each of the two or more sections. The contactor consumption management system for a circuit breaker according to claim 1 or 2.     The operation breaker determining means of the computer device is a section in which the distance relay operation section includes the counterpart end, and the magnitude of the cutoff current calculated from the recorded data of the oscilloscope is less than a predetermined value, The contact consumption control system for a circuit breaker according to any one of claims 1 to 3, wherein it is determined that an end bus fault has occurred.     The delay time setting means of the computer device corresponds to the distance relay section of the delay time table obtained by adding a fixed value to the set value of the time relay for the distance relay input via the digital input means. The contactor consumption management system for a circuit breaker according to any one of claims 1 to 4, wherein the system is set as a delay time.