JPH11178200A - Power distribution system - Google Patents

Abstract

(57) [Summary] [Problem] When an accident occurs in the conventional power distribution system, the ground fault information data from the remote control station is only bit data, and when an accident occurs, detailed analysis cannot be performed using only the accident detection bit. Solve the problem. SOLUTION: In a high voltage distribution network, a pole switch (20
1) Or means to control pole breakers (3a to 3c), detect ground faults and short circuits, measure distribution line voltage and current, and communicate
06), means for analyzing the zero-sequence voltage and zero-sequence current at the ground fault point when a ground fault occurs by fast Fourier transform (211), and ground fault waveform data previously input for each ground fault type Means for collating the frequency distribution of ground fault waveform data at the time (211)
A remote control station (202) having means (211) for instantaneously determining the type of ground fault and means (212) for transmitting the data at the request of the master station.

Description

DETAILED DESCRIPTION OF THE INVENTION

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention analyzes ground fault data at the time of an accident in a power distribution system, and automatically determines a ground fault type.
Store the discrimination data, waveform data and sequence,
By transmitting such information to the master station, it is possible to easily predict and analyze the cause of the accident within the sales office, investigate the cause of the accident, and improve the efficiency of recovery work. Related to the power distribution system including them.

[0002]

2. Description of the Related Art FIG. 6 shows a conventional substation 7 through a CB (breaker in a substation) 8, through a high-voltage distribution line, a pole switch 1a, 1b, 1c. , And remote control stations 2a, 2b, 2c, 4c,... Having the functions of control, voltage and current measurement, and a computer 5 and a master station 6 for managing them. 1 is a configuration block diagram illustrating a power distribution system provided. When a ground fault occurs, [ground fault point 9] the remote control station having the ground fault detection function, when the zero-phase voltage (V0), the zero-phase current (I0), the phase, and the ground fault detection time limit are established, the master station The ground fault information is returned in response to the state change request. The computer 5 specifies the accident section based on the ground fault information of the remote control station, separates the accident section, and performs accommodation of a healthy section.

For example, when an accident occurs at the accident point 9 in FIG. 6, the pole breaker 3c self-interrupts due to ground fault detection of the remote control station 4c, and the power failure range is suppressed to a minimum. At this time, the remote control station 4c returns an accident detection and cutoff bit, and the computer 5 determines and processes the accident section.

[0004]

However, in the prior art, when an accident occurs in the power distribution system, the ground fault information data returned from the remote control station is only bit data, and even if the accident section is specified. Until you arrive at the site and investigate, the true cause of the accident cannot be identified. If the accident disappears due to intermittent ground faults such as tree contact, the accident cause and the ground fault point cannot be specified, and the accident may occur again without recovery work.

Furthermore, in the prior art, an accident occurs in the distribution system, and the conditions of the operation sequence are not satisfied for some reason. For example, protection coordination cannot be performed, and the computer 5 of the distribution system cannot identify the accident section. In such a case, when performing an operation analysis for pursuing a cause, there is a problem that information of a remote control station which is an actual site only returns or stores only an accident detection bit, and a detailed operation analysis cannot be performed.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a first aspect of the present invention is to control the on / off of a pole switch or a pole breaker of a high voltage distribution network and to control the voltage of the distribution line. In a power distribution system consisting of remote control stations having means for measuring current, a zero-phase voltage and a zero-phase current at a ground fault point when a ground fault occurs are fast Fourier-transformed and input in advance for each ground fault type. The remote control station is provided with means for comparing the frequency distribution of the ground fault waveform data and the ground fault waveform data at the time of the accident to determine the type of ground fault, and for transmitting the data at the request of the master station. It is a power distribution system characterized by the following.

According to a second aspect of the present invention, there is provided a means for storing a ground fault waveform at the time of occurrence of an accident in a memory, and has a function of transmitting the ground fault waveform data when requested by a master station. 2. The power distribution system according to claim 1, comprising a remote control station.

According to a third aspect of the present invention, in a high-voltage distribution network, a ground fault, short-circuit detection, a pole breaker, a means for controlling and communicating the same, and a fault occurring in a power distribution system are provided. 2. The remote control station according to claim 1, further comprising means for individually storing the accident data and operation sequence, and further comprising means for extracting information from a local setting display through communication and analyzing the accident. It is a power distribution system.

According to a fourth aspect of the present invention, there is provided the power distribution system according to the third aspect, further comprising a setting display capable of extracting information from the remote control station and displaying accident data / operation sequence. .

In this way, the remote control station of the present invention analyzes the ground fault waveform (zero-sequence voltage, zero-sequence current) data at the time of occurrence of a ground fault in real time by FFT (Fast Fourier Transform) and inputs the data to a memory in advance. There is a special effect of comparing the obtained waveform data of the ground fault type with the frequency distribution and determining the ground fault type.

The remote control station stores the ground fault waveform data at the time of the occurrence of the ground fault in a memory, and transmits the discrimination data or the waveform data when the master station requests the data. Becomes possible.

Further, the remote control station according to the present invention provides a remote control station in the event that a ground fault occurs and the fault section is specified by a computer.
The ground fault data and the waveform data are transmitted from the remote control station that stores the ground fault data in the memory according to the data request of the sales office master station, and the cause of the accident can be specified by analyzing in advance in the sales office jurisdiction. This has the remarkable effect of being able to shorten the on-site ground fault factor investigation and restoration work.

Still further, the remote control station of the present invention provides a zero-phase voltage at the time of an accident of a local pole switch or local pole breaker,
Stores the zero-phase current level, its phase difference, duration, occurrence time (with a clock inside), and power failure information. After that, when performing operation analysis, if necessary, the information is displayed on the local setting display by communication if required. Can be obtained, detailed accident information can be obtained for each individual case, so that there is also an effect that it becomes a powerful clue for specifying an actual operation sequence and an accident section in performing operation analysis.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. [Embodiment 1] FIG. 1 is a diagram showing a change over time of request / transmission / reply transmission / reception among a computer, a master station, and a remote control station according to Embodiment 1 of the present invention. With reference to FIG. 1 and FIG. 6 showing the configuration of the entire system, the state of the operation of each part over time will be described.

As an example, suppose that a ground fault has occurred at the point 9 in FIG. In FIG. 1, when a ground fault occurs and ground fault conditions of zero-sequence voltage and zero-sequence current level are satisfied, the remote control station starts saving ground fault waveform data. When the condition of the ground fault detection time limit is satisfied, the slave station returns a ground fault information bit in response to the state change request of the master station. The remote control station finishes saving the ground fault waveform data and performs FFT analysis on the data. The frequency distribution of the ground fault data subjected to the FFT analysis is collated with the frequency distribution data of the ground fault type previously input to the remote control station memory to determine the ground fault type.

When the computer 5 specifies the faulty section where the faulty section has been separated and interchanged, the computer requests the remote control station 4c on the power supply side closest to the ground fault point for the ground fault type. Obtain the information on the type of entanglement If necessary, the ground fault waveform data is similarly requested to the remote control station for individual data, and is used as specific data of the cause of the accident before the site survey. This data is stored in the memory of the computer 5 and used as a ground fault phenomenon database together with the ground fault factors determined by the field survey.

FIG. 2 is a block diagram showing a circuit configuration of a remote control station and a pole switch (or a pole breaker) for monitoring and opening and closing a distribution line to which the present invention is applied. The operation of the remote control station will be described with reference to FIG. Inside the pole switch 201, the current detectors CT1, CT2, CT3 (r1,
r2 and r3 are resistances), a phase current is detected, a zero-phase current is detected in the ZCT, and each is supplied to the signal adjustment unit 204. Further, the voltage detectors PT1, PT2, PT3 (c1 to
c6) detects each phase voltage via a capacitor) and applies it to the signal adjustment unit 204. These detection input signals are introduced into the remote control station 202 via the signal cable 206, and the signal processing unit 211 here performs arithmetic processing of the signals.

That is, the analog signal from the pole switch 201 is pre-processed in the analog section 20 and analyzed and determined by digital operation in the digital section 30 in the next stage. Based on the resulting operation data, I /
Data transmission from the communication unit 212 or the like to the master station via the O device 10 and a control command to the direct control unit 209 are performed, and the control command from the master station is also transmitted to the control unit via the communication unit 212 / I / O device 10. 209.

The power supply unit 21 of the remote control station 202
Numeral 0 is supplied as A and C power from two places, a power source side and a load side, of a switch (not shown) installed on a distribution line (U, V, W phase) shown on the left side of FIG. And a control unit 209 that controls a switch and the like of the remote control station 202, and an operation unit 208 that outputs operation power based on a command from the control unit 209.
[Mainly a relay circuit] passes through a security unit [varistor or the like for protection against abnormal voltage from the outside] 207, passes through a control cable 205, and passes through an operation unit 20 of the pole switch 201.
Move to the operation of the device operation in 3. In this way, the present invention provides a remote control station 202 (installed on the same pole as the pole switch 201) for controlling the pole switch 201, which can determine the type of accident. , There is a characteristic.

[Second Embodiment] FIGS. 3A and 3B show a second embodiment of the present invention. FIG. 3A is a block diagram showing the configuration of a part of the circuit. FIG. 3B is a block diagram showing the internal configuration of a setting display. Fig. (C)
FIG. 3 is a diagram showing a flowchart showing an operation procedure. FIG. 4 is a time-series operation history diagram showing the operation of the present invention sequentially. FIG. 5 is a diagram showing an example of a display on the setting display at the time of the accident.

In the block diagram showing the configuration of a part of the circuit shown in FIG.
02 further includes a setting display 220, which is connected to a master station or the like by a communication cable 300. The internal configuration of the setting display 220 is, as shown in the block diagram of FIG. 3B, a communication connector 221, an interface (I / F) circuit 222, a communication control circuit (CPU), an operation panel (touch panel) 225, It comprises a display 224. FIG. 3 (c) is a flowchart showing the procedure of the operation of the on-site / setting display, and the operation is performed in the order from step 1 to step 6.

The sequential operation according to the second embodiment of the present invention will be described with reference to FIG. FIG. 4A shows a case of normal operation in a time series, and FIG. 4B shows a case of series trip operation in a time series. As an example, assume that the ground fault detection time limit of the CB is T1 and the ground fault detection time limit of the remote control station 4c is T2 in FIG. At this time, if a ground fault occurs at the ground fault point 9, the pole breaker 3c detects the ground fault and performs a self-cutoff, but for some reason, coordination cannot be taken, and the CB8 is also cut off, causing a series trip. Suppose.

At this time, since the remote control station 4c has returned the accident detection bit, it is considered that a ground fault has occurred at a point after the remote control station 3c. The machine 5 cannot clearly identify the ground fault point. So why CB
In order to verify whether the pole breaker 8 and the pole breaker 3c did not cooperate, as shown in FIG. 3 (a), the local remote control station (4c) 202
The setting display 220 is connected to the controller, and as shown in FIG. 5, the stored data such as the time limit of the ground fault occurrence, the zero-phase voltage, the zero-phase current level, the phase difference, the ground fault continuation time, and the power failure information are taken out. By doing so, the ground fault detection operation (setting) of the CB 8 can be compared with the operation of the pole breaker, and the operation sequence of the pole breaker 3c can be grasped. In this manner, the present invention makes it possible to quickly perform appropriate emergency measures for accident recovery means from the appropriate accident type determination.

[0024]

According to the present invention, ground fault type data and ground fault waveform data at the time of a ground fault in a distribution line can be collected for each terminal, and the cause of the fault can be specified in advance. A special effect of shortening the time can be achieved. Furthermore, since the accident data and the operation sequence at the time of the distribution line accident can be collected for each terminal, a remarkable effect that the operation analysis of the accident can be easily and reliably verified when the operation analysis of the accident is required is obtained.

[Brief description of the drawings]

FIG. 1 shows a computer, a master station,
Diagram of change over time in request / transmission / reply transmission / reception between remote control stations

FIG. 2 is a block diagram showing a circuit configuration of a remote control station and a pole switch or pole breaker to which the present invention is applied for monitoring distribution lines and switching lines;

FIGS. 3A and 3B are explanatory diagrams of Embodiment 2 of the present invention. FIG. 3A is a block diagram showing the configuration of a part of the circuit. FIG. 3B is a block diagram showing the internal configuration of a setting display. Diagram representing a flow chart representing

FIG. 4 is a time-series operation process diagram sequentially representing the operation of the present invention.

FIG. 5 is a diagram showing an example of a display of a setting display at the time of an accident according to the present invention.

FIG. 6 is a block diagram showing a configuration of a power distribution system as a conventional technique.

[Explanation of symbols]

1a, 1b, 1c, 1d, 1e, 1g Pole switch 2a, 2b, 2c, 2d, 2e, 2g Distance control station (for pole switch) 3a-3c Pole breaker 4a-4c Distance control station (For pole breaker) 5 Computer 6 Master station 7 Substation 8 CB 9 Ground fault point 10 I / O device (I / O device) 20 Analog section 30 Digital section 201 Pole switch 202 Remote control station 203 Operation section 204 signal adjustment unit 205 control cable 206 signal cable 207 security unit 208 operation unit 209 control unit 210 power supply unit 211 signal processing unit 212 communication unit 213 communication cable 220 setting display 221 communication connector 222 I / F circuit 223 communication control circuit ( CPU) 224 Display (monitor) 225 Operation panel (touch panel)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H02H 7/26 H02H 7/26 MH02J 13/00 301 H02J 13/00 301D

Claims (4)

[Claims] 1. A power distribution system comprising a remote control station having means for controlling the switching of a pole switch or a pole breaker of a high voltage distribution line network and measuring the voltage and current of a distribution line. When a fault occurs, the zero-sequence voltage and zero-sequence current at the ground fault point are subjected to fast Fourier transform, and the frequency distribution of the ground fault waveform data input in advance for each ground fault type and the frequency distribution of the ground fault waveform data at the time of the accident are compared. A power distribution system, characterized in that a remote control station is provided with means for judging the type of fault and means for transmitting the data at the request of the master station. 2. A remote control station having means for storing a ground fault waveform at the time of occurrence of an accident in a memory, and having a function of transmitting ground fault waveform data when requested by a master station. The power distribution system according to claim 1, wherein: 3. In a high-voltage distribution network, means for detecting a ground fault and a short circuit, as well as a pole breaker and its control and communication means, and separate fault data and operation sequence when a fault occurs in a power distribution system. 2. The power distribution system according to claim 1, comprising a remote control station having means for storing, and means for extracting information from the local setting display by communication and analyzing the accident. 4. The power distribution system according to claim 3, further comprising a setting display for extracting information from the remote control station and displaying accident data and an operation sequence. [0001]