JPH03251039A - Fault zone detector - Google Patents

Abstract

PURPOSE:To shorten time required for detecting a fault zone by feeding fault detection information to the oscillator of a slave station when the operation of a selection relay reaches a fault detection slave station, detecting it by a fault information detection sensor of a a master station, and signal processing it. CONSTITUTION:When a power distribution line fault occurs, an output contact Ryn1a is closed. On ther other hand, a slave station selection relay 35 turns ON, OFF output contacts Ry1a-Ry1n, and outputs oscillation frequencies f1-fn corresponding to a slave station ON from oscillators OS1-OSn to slave stations 11-(n) at each time. The stations 11-(n) start oscillating only when the resonator Fn of own station coincides with the frequency to close output contact Ryn2a. In this case, if the oscillating frequency fn coincides with the station (n) which has detected a fault, a closed circuit is formed between communication lines C10 and C11 to insert an impedance, and a high frequency current flows to the oscillator OSn. A signal processor 30 detects the current through fault information detection sensors 31, 32 to judge the fault detection slave station ON.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention provides a fault section detection device that detects a fault section at high speed in order to take into consideration the balance of power supply and demand and to quickly restore the power supply when an accident occurs on a power distribution line. It is related to.

[Conventional technology]

Non-grounded power distribution systems use sectional switching elements (hereinafter referred to as sectional switches) equipped with fault detection sensors that divide distribution lines into predetermined sections to minimize power outage sections and to quickly detect failure points in the event of a distribution line failure. ) and a loop point switching element (hereinafter referred to as a loop point switch) with a failure detection sensor at the interconnection point that performs reverse power interchange power transmission.

FIG. 3 is a distribution system diagram in which, for example, distribution lines output from three distribution substations are interconnected by a loop point switch, and in the figure, As/s.

B srs and Cs/s are respectively distribution substations, 1 is the bus of distribution substation A srs, 2 is distribution substation Bs
/s busbar, 3 is the distribution substation Csrs busbar, CBI
I and CBk1 are circuit breakers for distribution lines connected to bus 1, CB21 is a circuit breaker connected to bus 2 of distribution substation B s/s, and CB51 is a circuit breaker connected to bus 3 of distribution substation Cs/s. The connected circuit breaker Fil is a distribution line that is connected to the other terminal of the distribution circuit breaker CBII and supplies power to consumers, and Fkl is connected to the other terminal of the distribution circuit breaker CBk1 and supplies power. Supply distribution line, also F2
1 and F31 are also power distribution lines. Also, 5Sll~
5SI3 and SSk 1 to 5Sk3 are division switches for dividing the distribution lines Fil and Fkl at appropriate intervals, 5
SIO is a loop point switch for interconnecting power distribution line Fil and power distribution line F21, 513kO is a loop point switch for interconnecting power distribution line Fkl and power distribution line F31, S11.
S L2. S13 is breaker CBII, section switch 5
This shows the section of the distribution line Fil divided by S11.5S12 and the loop point switch 5510, and the circuit breaker CB1
The first section, the second section of the distribution line Fil from the section closer to 1,
In the third section, Ski, Sk2. Sk3 breaker CB
k1, section switches 5Skl, 5Sk2, and loop point switch 5SkO, each section of the distribution line Fk, 1 is shown.
The first section, second section, and third section of Also, lL1
2.13 and kl, 2. 3 is section switch 5SII~
5S13 This is a slave station for 5Skl to 5Sk3. Furthermore, 1O-1 to 13-1 and kO-1 to 3-1 are section switches 5SII to 5S13 and loop point switches 5S, respectively.
The sectional switches are controlled from the slave station using the control lines of the IO and the sectional switches 5Sk1 to 5Sk3 and the loop point switch 5SkO, and the failure state of each section is detected. 4
0 is the master station, CI, and C2 are the master station 40 and slave stations 10 to 13.
This is a communication line for transmitting information between 3 and 3.

Next, the operation will be explained. First, section switch 5SII
~5S13, 5Skl ~5Sk3 and loop point switch 5
SIO and 5SkO are slave stations 10 to 13. each equipped with a failure detection function. It has 3 in ko-. The master station 40 is connected to each of the slave stations 10 to 13. In order to collect failure detection information for kO-3, information is periodically collected by a polling method via communication lines C1 and C2. At that time,
For example, when a one-wire ground fault occurs in the third section S13 of the power distribution line Fil, a ground fault current flows through the power distribution line 11 as indicated by an arrow. In order to prevent a power outage in the healthy section of the fourth section S14, which is located further on the load side than the third section S13, the distribution NIAII is operated before the circuit breaker CBII of the distribution substation As/s operates to shut off (the circuit breaker is Approximately 0.
It is necessary to turn on the loop point switch S10 (activated in 5 to 1.0 seconds) to form a loop, and then disconnect the section switches 3312 and 5S13 at high speed. In this case, before turning on the loop point switch 5SIO1 or 5SkO, the master station 40 determines the failure section based on the failure detection information collected from the slave stations 3311-3S12 using a sequential polling method, and selects which loop point switch 5SIO1 or 5SkO. Determine which loop point switch will have the least impact on the system by turning it on, and then select the best loop point switch to disconnect. Determining this fault section is difficult because polling time to collect fault detection information from all slave stations takes a lot of time, and when a two-wire ground fault occurs, the slave station power supply decreases due to a drop in the line voltage of the distribution line. There was a gap in the failure detection information of the station, and it took a lot of time to correct the failure area determination.

Furthermore, in the worst case, it may become impossible to determine a faulty section. Conventionally, it took more than 0.5 to 1.0 seconds to detect the fault section, check the cross current detection value, and select the loop point switch, so it was difficult to cut off the distribution line at the distribution substation. When a faulty section was tripped, the faulty section was detected, the faulty section was disconnected, and power was transferred to the healthy section by re-closing, re-closing, and opening/closing the switch manually/programmed.

[Problem to be solved by the invention]

Since the conventional fault section detection device is configured as described above, it detects a fault section by collecting fault detection information of all slave stations when a ground fault occurs. (Because there are many connection changes to communication lines, the polling order changes and it is necessary to collect all information), processing to correct missing slave station information due to grid voltage drop at the time of an accident, and loop point switch selection operation. Since the time required for the distribution line breaker to operate was longer than 0.5 to 10 seconds, a power outage occurred in healthy sections other than the faulty section, and as the power outage became longer, the power outage in the faulty section Recovery was delayed. As a result, there has been a problem that, for example, various electronic products such as OA equipment, which are a load on the power distribution line, are greatly affected.

This invention was made in order to solve the above-mentioned problems, and it is possible to detect a faulty line at high speed and collect fault information of slave stations related to the faulty line at high speed regardless of the presence or absence of grid voltage. The object of the present invention is to obtain a faulty section detection device that reduces the time required for section detection.

[Means to solve the problem]

A fault section detection device according to the present invention operates on a slave station provided in each section of a distribution line connected to a distribution substation, and receives fault detection information of the distribution line detected by a fault detection section of the slave station to open/close the fault section. A master station that controls the device, a latch-type failure detection relay energized by the detection operation of its failure detection unit, and a slave station selection relay of the master station are shifted to select an oscillation frequency corresponding to the slave station, There are multiple oscillators that output to the communication line, a selection relay that resonates and is energized when the frequency of the resonant section matches the oscillation frequency, and when the operation of the energized selection relay reaches the fault detection slave station. The failure detection information flows between the oscillator of the corresponding slave station, and the failure information detection sensor of the master station detects this and processes the signal. It is now possible to collect information in a short time, and it is also possible to collect slave station information and detect faulty sections at high speed and reliably even during a drop in system voltage or a power outage due to an accident or the like.

[For production]

The master station in this invention has a plurality of oscillators that output oscillation frequencies corresponding to the slave stations, and sequentially switches the slave station selection frequency and transmits to the slave stations.

A resonator is provided in the selected slave station, and the resonator resonates with the frequency to energize the selection relay.

At this time, if the operation of the selection relay matches that of the failure detection slave station, a predetermined impedance is inserted into the communication line and the failure detection information is transmitted to the master station, so the master station transmits the failure detection information to the communication line. data is easily collected through the network, and faulty slave stations can be detected in a short time.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, the same parts as in FIG. 3 are designated by the same reference numerals. In FIG. The existing high-speed overcurrent detector 51 is used to detect a short circuit accident, and the existing high-speed ground fault direction detector 67G is used to detect a ground fault accident. Ryo
is a latch type failure detection relay, and RVh+m is the failure detection relay described above. + output contact, Fn is a resonant section consisting of a capacitor Cn and an inductance Ln, Ry9□ is a selection relay that is energized when the resonant section Fn resonates at a certain frequency, Z is a current limiting resistor, CIO.

C1l is a communication line.

In FIG. 2, 40 is a master station, and 3o is a signal processing unit, which receives failure information when a slave station n detects a distribution line failure from a voltage detection sensor 31 or a current detection sensor 32 as a failure information detection sensor. and it works. 35 is a slave station selection relay, with output contacts Ry+m +Ry+a,...R)'
l1m is sequentially and cyclically switched. (Although not shown, the slave station selection relay 35 may start operating in response to the fact that the master station 40 detects a distribution line failure in another failure detection unit.) f1 to f, l are slave stations n
This is a slave station compatible oscillator provided corresponding to the resonant section Fn.

Next, the operation will be explained. First, when a distribution line failure such as a short circuit or a ground fault occurs in the distribution line Fll, the failure detection unit Dn equipped with an overcurrent detector, a ground fault direction detector, etc. is activated and energizes the latch type failure detection relay RV1. Then, its output contact Ry□ is closed. On the other hand, the slave station selection relay 35 of the master station 40 has its output contact RV1m, R)' rb
+...R)'+- is cyclically turned on and off for a predetermined period of time, and each time, the slave station N
Transmission frequencies ft', fz, ... f7 corresponding to O are transmitted from the oscillators O3I, O32゜O33, .O3n to the communication line CI
slave stations 11, 12 . ...Output to n. Each slave station 11. 12. -n is the oscillation frequency f+,
fz.

. . f is received from the communication lines CIO and C1l, resonance starts only when the resonant lower part Fn of the local station matches the frequency, and a resonant current flows to energize the selection relay R'/at. Then, the output contact R'J-ta is closed for a certain period of time. At this time, when the oscillation frequency f7 matches the slave station n whose failure has been detected, a current limiting resistor Z,
Output contact R)',,2S.

A Ry-ra closed circuit is formed, an impedance is inserted, and a high frequency current flows between it and the oscillator O3n. The signal processing unit 30 of the master station 40 has failure information detection sensors 31 and 32.
The high frequency current is detected through the oscillator, and the failure detected slave station number is determined from the timing of detection of the oscillation frequency corresponding to the slave station number. In response to this, the master station 40 directly connects the section switch SS
Moving on to the control operation of n and the loop point switch 5SkO.

Other than that, the subsequent control operations of the sectional switch related to ground faults and short circuits proceed in the same manner as in the conventional example.

Note that although the above embodiments have described latch-type failure detection relays, these may also be configured with semiconductor circuits.
The same effects as in the above embodiment are achieved.

In addition, although we have described an example in which a high-speed overcurrent detector and a high-speed ground fault direction detector are used as fault detection units in slave stations, we have also described methods using other principles for detecting distribution line faults, such as impedance relays or fault point A scalar amount of current may be used, and the same effect as in the above embodiment can be achieved.

Furthermore, although frequency is used as the slave station selection signal, voltage levels, current levels, phases, etc. based on other principles may also be used.

Furthermore, although the LC series resonance is illustrated as the resonance section, other resonance circuits may be used and the same effects as in the above embodiments can be achieved.

〔Effect of the invention〕

As described above, according to the present invention, when failure information of the distribution line is received by the plurality of slave stations provided on the distribution line and the failure detection unit in the slave stations, the master station that controls the switch of the distribution line; A plurality of oscillators installed in the master station oscillate at different frequencies in response to the slave stations, a resonator that resonates and energizes the selection relay when the oscillation frequency matches that of the slave station, and the operation of the resonator. When the fault detection information matches the fault detection slave station, it transmits the fault detection information to the master station, and since it is configured with a signal processing section that collects and processes the signal, there is no need for complicated protocols or transmission formats between the master station and slave stations. In addition to quickly detecting faulty sections, power is supplied from the master station even during power outages.
This has the effect of being able to collect failure detection information held on the slave station side.

Furthermore, since the signal level can be increased, a device with excellent noise resistance and high reliability can be obtained.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of a slave station according to an embodiment of the present invention, and FIG.
The figure is a block diagram showing a circuit configuration for collecting slave station information, and FIG. 3 is a configuration diagram of a conventional fault section detection device. In the figure, Fil is a distribution line, SSn is a switch, and 11-
n is a slave station, Dn is a failure detection unit, 40 is a master station, R)l□ is a failure detection relay, 35 is a slave station selection relay O81, 032
, -03n is an oscillator, Fn is a resonance section, R)l2 is a selection relay, and 30 is a signal processing section. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] A slave station installed at a switch installation point provided for each section of a distribution line connected to a distribution substation receives fault detection information on the distribution line detected by a fault detection unit of the slave station. A master station that controls the switch, a latch-type failure detection relay energized by the detection operation of the failure detection section, and a slave station selection relay in the master station are shifted to select an oscillation frequency corresponding to the slave station. A plurality of oscillators that output to a communication line, a selection relay of the slave station that resonates and is energized when the resonance part of the slave station matches the oscillation frequency, and a malfunction in the operation of the energized selection relay. A signal processing unit that transmits fault detection information between the detected slave station and the oscillator of the corresponding slave station when the detected slave station matches, detects the failure detection information by a failure information detection sensor of the master station, and performs signal processing. Section detection device.