JP5944177B2 - Protective relay device and protective relay system - Google Patents

Description

  Embodiments described herein relate generally to a protective relay device and a protective relay system.

  In order to maintain the safe operation of the power system by detecting the accident that occurred in the bus, transformer, transmission line, and other power system equipment, the protective relay device is disconnected from the healthy power system. is set up.

  When the power system facility is an important system, a current differential protection relay device having excellent fault section discrimination performance is often applied as the protection relay device.

  As shown in FIG. 15, the current differential protection relay device introduces a current flowing through both ends of the protection target facility, performs a differential calculation, and determines an accident inside the protection range. When the current differential protection relay device is applied for power transmission line protection, because there is a physical distance, current instantaneous values obtained at the same time at both ends of the power transmission line (between power transmission line terminals) Data is transmitted to each other using a transmission line, and differential operation is performed using the instantaneous value data of the local current and the instantaneous value data of the transmitted partner current, and the operation is determined. When the current differential protection relay device for the transmission line is a digital type, the PCM transmission method is used as the transmission method of the instantaneous current value data, so it is generally called “PCM relay”. Is done.

The differential calculation in the PCM relay uses a differential current (Id) obtained as a vector sum of currents at each end as an operation amount, a suppression amount (Σ | I |), and a minimum operation sensitivity (Idk). It is determined that there is an accident within the protection zone when the comparison formula is established.

  As shown in FIG. 16, the sampling frequency and the calculation interval of the grid electricity amount in the conventional PCM transmission system are determined based on an electrical angle of 30 degrees, so that when the commercial frequency is 50 Hz, 600 Hz and 60 Hz In this case, the frequency is 720 Hz.

  In addition, the current differential protection relay device uses the fact that the transmission delay time of the uplink and downlink transmission lines is the same as means for synchronizing the sampling timing of data at each terminal, so that transmission on the transmission line If there is a delay time variation, it will occur as an error of the power system fault detection means.

  For this reason, the transmission path used in the PCM relay employs a method capable of setting a transmission delay time within a predetermined range, and 54 kbps, 1.5 Mbps, etc. are used as the transmission speed. . However, since these transmission systems are actually power-specific standards and are expensive, it is considered to use a general-purpose transmission system with high capacity, low cost, and high availability such as high-speed Ethernet (registered trademark). Has been.

“Standard concept of system protection relay system (digital edition)”, Director-General for Protection Control Section, Engineering Division, Electric Power Industry Federation, March 1992, p31, 116, 224-225

  However, in the protective relay device as described above, when the instantaneous current value data is transmitted using the general-purpose transmission method, if the relay relay device of multiple routes and other applications share the network, the transmission data is It is expected that the transmission delay time fluctuates due to congestion. For this reason, even if a large-capacity general-purpose transmission technique is applied, there is a disadvantage that the amount of transmission information cannot be increased.

  Therefore, from the viewpoint of suppressing the above-described fluctuation in transmission delay time, it is required to reduce the amount of transmission data and the number of data transmissions at all times.

  The problem to be solved by the present invention is to provide a protection relay device and a protection relay system that can reduce the amount of transmission data and the number of times of data transmission at all times, and can suppress fluctuations in transmission delay time.

  The protection relay device of the embodiment is provided at each terminal facing the power system.

  The protective relay device includes acquisition means and transmission means.

  The acquisition means acquires electric quantity data from the power system at every sampling period t.

The transmission means transmits M electrical quantity data (2 ≦ M ≦ N) of electrical quantity data acquired at each sampling period t at every transmission period tN that is N times the sampling period t. Transmit to the protective relay device at the other terminal.
The transmission means includes
When an accident detection signal is received from an accident detection means provided in the electric power system, at least NM (where N> M) electric quantity data not transmitted among the acquired electric quantity data Means for transmitting to the protective relay device of the counterpart terminal is provided.

It is a schematic diagram which shows the system | strain to which the protective relay apparatus which concerns on 1st Embodiment was applied. It is a schematic diagram which shows the protection relay apparatus and its periphery structure in the same embodiment. It is a schematic diagram which shows the example of the transmission frame in the same embodiment. It is a schematic diagram which shows the example of the sampling timing and transmission timing in the same embodiment. It is a schematic diagram which shows the example of the sampling timing and transmission timing in the same embodiment. It is a flowchart for demonstrating operation | movement of the protection relay apparatus which concerns on 2nd Embodiment. It is a schematic diagram which shows the example of the sampling timing and transmission timing in the same embodiment. It is a schematic diagram which shows the example of the sampling timing and transmission timing in the same embodiment. It is a schematic diagram for demonstrating the expansion differential calculation system in the protection relay system which concerns on 3rd Embodiment. It is a schematic diagram which shows the structure of the protection relay system in the embodiment. It is a schematic diagram which shows the protection relay apparatus and its periphery structure in the same embodiment. It is a schematic diagram which shows the example of the operation state of the protection relay system which concerns on 4th Embodiment. It is a schematic diagram which shows the structure of the protection relay apparatus in the protection relay system in the embodiment. It is a schematic diagram which shows the structure of the protection relay apparatus in the protection relay system which concerns on 5th Embodiment. It is a schematic diagram which shows the conventional system | strain. It is a schematic diagram which shows the conventional sampling timing and transmission timing.

  Each embodiment will be described below with reference to the drawings. Each of the following devices can be implemented for each device with either a hardware configuration or a combination configuration of hardware resources and software. As the software of the combined configuration, a program that is installed in advance on a computer of a corresponding device from a network or a storage medium and that realizes the function of the corresponding device is used.

<First Embodiment>
FIG. 1 is a schematic diagram showing a system to which the protective relay device according to the first embodiment is applied.
In the present embodiment, from the viewpoint of reducing the amount of transmission data at all times and the number of data transmissions, instead of the protective relay devices A-1 ′ and B-1 ′ shown in FIG. Are provided with protective relay devices A-1 and B-1, respectively. Since the protective relay devices A-1 and B-1 have the same configuration, in this specification, one protective relay device A-1 will be described as a representative example. The term “protective relay device” may be read as “transmission line protective relay device” or “power system protective relay device”.

  As illustrated in FIG. 2, the protection relay device A-1 includes an acquisition unit 101, a transmission unit 102, a calculation unit 103, and an output unit 104.

  Here, the acquisition unit 101 has an acquisition function of acquiring electric quantity data from the power system at every sampling period t. As the acquisition unit 101, for example, the electric quantity of the self-current obtained by the current transformer (CT) is passed through the input converter and the analog filter in the analog-digital conversion unit, and the passed electric quantity is sampled. Sampling is performed by the holding means, and the data is converted into electric quantity data (current instantaneous value data) as digital data by the analog / digital conversion means and output to the transmission unit 102. The acquisition unit 101 is not limited to a configuration that acquires current instantaneous value data using a current transformer (CT), and may be configured to acquire voltage instantaneous value data using a voltage transformer (VT).

  The transmission unit 102 supplies M pieces of electric quantity data (where 2 ≦ M ≦ N) among electric quantity data acquired for each sampling period t for each transmission period tN that is N times the sampling period t. It has a transmission function to transmit to the protective relay device B-1 of the counterpart terminal. Moreover, the transmission part 102 has a function which receives the electrical quantity data transmitted from the protection relay apparatus B-1 of the other party terminal, and sends it out to the calculating part 103.

  The calculation unit 103 calculates the difference described above based on the electrical quantity data transmitted from the transmission unit 102 to the protective relay device B-1 and the electrical quantity data received by the transmission unit 102 from the protective relay device B-1. It has a function to execute motion calculation and motion determination.

  As a result of the operation determination, the output unit 104 has a function of outputting a trip command to the circuit breaker CB to be controlled by the own device A-1 when it is determined that an accident exists.

  Next, the operation of the protective relay device configured as described above will be described with reference to FIGS.

  In the protective relay device A-1, the acquisition unit 101 acquires electrical quantity data from the power system at each sampling period t.

  The transmission unit 102 supplies M pieces of electric quantity data (where 2 ≦ M ≦ N) among electric quantity data acquired for each sampling period t for each transmission period tN that is N times the sampling period t. It transmits to the protective relay device B-1 of the other party terminal.

  In this way, in the protective relay device A-1, the transmission interval of the electric quantity data used in the accident detection is set to N times the sampling period t, and the data for M sampling is transmitted and used in the general-purpose transmission method. By reducing the number of transmissions in the header / footer portion of the transmission format, the total transmission data amount is suppressed.

  As an example of the general-purpose transmission method, FIG. 3 shows a transmission format when UDP / IP is used on the Ethernet. As shown in the figure, the amount of header / footer data in one transmission is 18 bytes when only Ethernet is used, and 46 bytes when UDP / IP is used on Ethernet.

  Here, as shown in FIG. 4, when N = 4 and M = 4, information equivalent to the conventional method can be used, and the binary addition method used in the PCM relay (conventional method) (non-patent) It is possible to calculate the amplitude using the reference 1 on page 31). However, as the number of transmissions is reduced, the header / footer information is reduced and the transmission information amount is reduced as a whole. I understand that

  As shown in FIG. 5, even when N = 6 and M = 2, it is possible to calculate the amplitude by applying the amplitude square method (described on page 31 of Non-Patent Document 1). It can be seen that even if the values of N and M are not equal, it can function as a protective relay device.

  As described above, according to the present embodiment, M electrical quantity data (where 2 ≦ M ≦ N) of the obtained electrical quantity data is transmitted to the other party every transmission cycle tN that is N times the sampling period t. With the configuration of transmission to the terminal protection relay device B-1, it is possible to reduce the amount of transmission data at all times and the number of data transmissions, thereby suppressing fluctuations in transmission delay time.

  Supplementally, by collecting and transmitting a plurality of sampling data, it is possible to obtain the effect of reducing the number of transmissions and reducing the amount of transmission data.

<Second Embodiment>
Next, the protective relay device according to the second embodiment will be described. The present embodiment is a modification of the first embodiment, in which the transmission unit 12 transmits detailed data after an accident is detected.

  Specifically, when the transmission unit 12 receives an accident detection signal from an accident detection means (not shown) provided in the power system, in addition to the functions described above, the transmission unit 12 transmits the acquired electric quantity data. It has a function of transmitting at least NM electrical quantity data that has not been transmitted to the protective relay device B-1 of the counterpart terminal.

  Here, as the accident detection means, for example, a simple and highly sensitive accident such as a differential OC, an overcurrent relay at its own end, or an accident detection (FD) relay provided to reduce the malfunction rate of the protection relay. A device for detecting the occurrence of an accident by the discrimination calculation can be used as appropriate.

  Next, the operation of the protective relay device configured as described above will be described with reference to FIGS.

  As shown in FIG. 6, the acquisition unit 11 and the transmission unit 12 of the protective relay device A-1 operate in the same manner as in the first embodiment (ST1). An accident detection means (not shown) performs simple accident determination (ST2). If no accident is detected as a result of the simple accident determination (ST3; N), the protective relay device A-1 continues the operation of step ST1.

  If an accident is detected as a result of the simple accident determination (ST3; Y), the accident detection means transmits an accident detection signal to the protective relay device A-1.

  When receiving the accident detection signal, the transmission unit 12 of the protective relay device A-1 receives at least NM pieces of electric quantity data (detailed data) that are not transmitted from the electric quantity data acquired by the acquisition unit 11. ) Is transmitted to the protective relay device B-1 of the counterpart terminal (ST4). The at least NM electrical quantity data that have not been transmitted are used for detailed accident determination involving high-precision computation in the computation unit 13 of the protective relay device B-1 (ST5).

  For example, as shown in FIG. 7 where N = 4 and M = 2, if an accident occurs at the timing of A6 and an accident is detected at the timing of A10, detailed data from the point in time when the predetermined sampling number is traced back Is transmitted to the other end to make a detailed accident determination. Further, after the accident is detected, as shown in FIG. 8, it is possible to perform sequential transmission by setting N = 1 and M = 1 for a predetermined period, and continuously perform detailed accident determination. Also, if the information transmitted to the other end as detailed data and the data that has already been transmitted have the same accuracy, it is more than necessary even in the event of an accident by selectively transmitting information that has not been transmitted in the past. Another method that does not increase the amount of transmitted data is also conceivable.

  In any case, when it is determined that there is an accident as a result of the detailed accident determination (ST6; Y), the output unit 14 of the protective relay device B-1 outputs a trip command to the circuit breaker CB (ST7). The circuit breaker CB is opened by a trip command and performs accident removal of the power system.

  In general, digital relays have a window length for the calculation of the effective value described above, and a digital filter is provided to eliminate the effects of harmonic components. There is a delay time until detection.

  In the case of a PCM relay, although it depends on the magnitude of the accident current and the phase at which the accident occurs, it takes about 20 ms from the occurrence of the accident to the detection of the accident if the transmission delay time is excluded. For this reason, if accident detection is performed in 10 to 15 ms using a highly sensitive accident determination method, detailed data transmission and accident determination calculation using the detailed data can be performed in the remaining 5 to 10 ms, the accident can be removed. This time can be made equal to that of the conventional method.

  The transmission capacity of the general-purpose transmission method is several tens to several thousand times that of the transmission method used by the PCM relay. For this reason, even if the detailed data is transmitted after the accident is detected, the time required for transmitting the detailed data is sufficiently shortened, so that the time from the accident detection to the accident removal can be maintained.

  In this specification, the case where the sampling frequency and the calculation interval coincide with each other has been described. However, in recent digital protection relay devices, the electric quantity data is acquired at a sampling frequency several times as large as the calculation interval, and the average is obtained. A method of performing transmission processing, etc., and compressing the error of the acquisition unit 101 before transmission is common. For this reason, it is also possible to make the electric quantity data transmitted at the time of an accident n times the calculation interval. In this case, if there is an accident recording function or fault location function as an additional function of the power line protection relay device, it is possible to transmit information used for these functions without increasing the normal transmission load. It becomes.

  As described above, according to the present embodiment, when the accident detection signal is received, at least NM pieces of electrical quantity data (detailed data) that have not been transmitted among the obtained electrical quantity data are protected for protection of the counterpart terminal. With the configuration of transmission to the electric device B-1, in addition to the effects of the first embodiment, detailed data can be transmitted to the protective relay device B-1 on the counterpart terminal side after detecting an accident.

  Supplementally, the amount of transmission data at all times can be reduced by thinning transmission. Further, since the protective relay device B-1 on the counterpart terminal side performs the accident determination using the detailed data transmitted after the accident detection, there is no reduction in the calculation accuracy. Furthermore, by using a highly sensitive relay element, the time from the occurrence of an accident to the detection of the accident can be shortened. Even if detailed data is subsequently transmitted and differential calculation is performed, the time required to eliminate the accident is not different from the conventional method.

<Third Embodiment>
Next, the protection relay system according to the third embodiment will be described, but before that, the outline of the present embodiment will be described.

  In the PCM relay, normally, the electric quantity data sampled by the protective relay device A-1 and the protective relay device B-1 are transmitted, differential calculation is performed, and an accident is determined.

  9, the current Ia-1 detected by the protective relay device A-1 is equal to the current Ia-2 detected by the protective relay device A-2 and the protective relay device A-. It is obvious that 3 is equal to the sum of the detected currents Ia-3.

  Therefore, when there is a defect in the protective relay device A-1, by performing a differential operation using Ia-2, Ia-3 and the current Ib-1 detected by the protective relay device B-1 The protection function between the protective relay device A-1 to the protective relay device B-1 can be continued. This is called an enlarged differential calculation method.

  As shown in FIG. 10, the current data of the protective relay devices A-2 and A-3 are transmitted to the protective relay device B-1 via the transmission device 200, and differential calculation is performed. At this time, the protective relay device A-2 to the protective relay device B-1, the protective relay device A-3 to the protective relay device B-1, and the protective relay device A-2 to the protective relay device A-3. Therefore, the amount of data transmitted between the A substation and the B substation increases.

  Since the restrictions on the transmission system are usually loose within substations and stricter between substations, the protection relay device A-2 is used by using the first transmission network NW1 in the substations with relatively few restrictions on the amount of transmission data. Transmit the current value of the protective relay A-3, calculate the differential current (Id) and the suppression amount (Σ | I |) of A-2 and A-3 in A-2, and then transmit the data amount The transmission to the B substation is performed via the second transmission network NW2 in which restrictions on the network are relatively strict. As a result, transmission can be performed only between the protective relay device A-2 and the protective relay device B-1.

At that time, the protective relay device A-2 that performs calculation of the amount of electricity in the substation is called a representative device.

  The above is the outline of the present embodiment. Next, the configuration of the protective relay device A-2 as a representative device will be described with reference to FIG. The representative device is connected to the first transmission network NW1 having a restriction on the amount of transmission of electrical quantity data among the plurality of protection relay devices A-1 to A-3, B-1 in the protection relay system. Any protective relay device (eg, A-2).

  The protection relay device A-2 as a representative device includes a calculation unit 105 and a calculation data transmission unit 106 in addition to the units 101 to 104 described above.

  When a failure is detected from one of the other protective relay devices A-1 and A-3 (for example, A-1) connected to the first transmission network NW1, the calculation unit 105 detects the first transmission network NW1. Protective relay device A in which a defect has been detected based on the electrical quantity data transmitted from still another protective relay device A-3 connected to the device and the electrical quantity data acquired by the acquisition unit 101 of the own device -1 has a calculation function for calculating electric quantity data that is estimated to be acquired when the defect does not occur.

  The calculated data transmission unit 106 transmits the electric quantity data calculated by the calculation unit 105 to the protection relay device B-1 at the counterpart terminal via the second transmission network NW2 that is more restrictive than the first transmission network NW1. Has a calculation data transmission function.

  Next, the operation of the protective relay system configured as described above will be described.

  The protective relay device A-1 operates in the same manner as in the first embodiment.

  Subsequently, it is assumed that a failure is detected in the protective relay device A-1.

  The calculation unit 105 in the protection relay device A-2 of the representative device, when a failure is detected from the protection relay device A-1, still another protection relay device A- connected to the first transmission network NW1. 3 is detected based on the electric quantity data (current Ia-3 instantaneous value data) transmitted from 3 and the electric quantity data (current Ia-2 instantaneous value data) acquired by the acquisition unit 101 of the own device. Electricity data estimated to have been acquired when no failure occurred in the protective relay device A-1 (current Ia-1 instantaneous value data = current Ia-2 instantaneous value data + current Ia-3 instantaneous value data) Is calculated.

  The calculated data transmission unit 106 transmits the calculated electric quantity data to the protection relay device B-1 at the counterpart terminal via the second transmission network NW2 that is more restrictive than the first transmission network NW1.

  As described above, according to the present embodiment, one of the protective relay devices (for example, A-2) connected to the first transmission network NW1 having a restriction on the transmission amount of the electric quantity data is detected as defective. The amount of electricity estimated to be acquired by the protection relay device A-1 is calculated, and the amount of electricity is protected via the second transmission network NW2 that is more restrictive than the first transmission network NW1. With the configuration of transmission to the relay device B-1, in addition to the effects of the second embodiment, the amount of transmission data of the second transmission network NW2 with severe restrictions can be reduced.

  Supplementally, for example, after calculating the differential current and the suppression amount between the protection relay devices A-2 and A-3 of the first transmission network NW1 with a loose transmission constraint, the transmission data amount is severely limited (first section). By transmitting the electric quantity data through the two transmission networks NW2), it is possible to reduce the transmission data quantity in a section where the restriction of the transmission data quantity is severe.

<Fourth Embodiment>
Next, the protection relay system according to the fourth embodiment will be described, but before that, the outline of the present embodiment will be described.

  Unlike the third embodiment in which the representative device is fixed, the present embodiment has a configuration in which the representative device can be switched. Supplementally, in the fourth embodiment, since the amount of electricity to be used for the expanded differential calculation differs depending on the operating state of the system in the third embodiment, a representative device suitable for performing the amount of electricity calculation is selected as the system of the system. It is in a form that changes depending on the operating state.

  For example, as in the operation information shown in FIG. 12 (a), when the busbar breaker is closed, the representative device for the enlarged differential calculation using the currents of the protective relays A-2 and A-3 Is the protective relay device A-2. Here, as in the operation state shown in FIG. 12B, when the busbar breaker is opened, the electrical quantity data acquired by the protective relay device A-2 is not necessary for the enlarged differential calculation. . Further, since the circuit breaker CB to be controlled by the protective relay device A-2 is opened, the protective relay device A-2 can be stopped. For this reason, the representative device is switched to the protective relay device A-3.

  In the operation state shown in FIG. 12C, it is also possible to stop the protective relay device A-3 on the bus side that is not used. Therefore, the representative device is switched to A-2 or A-4.

  In addition, when the state of the switch (setting unit) for setting the operation state of the representative device is excluded or when a test setting is made, the representative device has a function of switching to another device.

  The above is the outline of the present embodiment. Next, the configuration of the protective relay devices A-1 to A-4 that can be switched to the representative device will be described with reference to FIG. In addition, each protection relay device A-1 to A-4 is the restriction | limiting of the transmission amount of electrical quantity data among several protection relay device A-1 to A-4, B-1 in a protection relay system. Is connected to a first transmission network NW1. Moreover, since each protection relay apparatus A-1 to A-4 has the same configuration, the protection relay apparatus A-2 will be described as a representative example.

  The protection relay device A-2 includes a setting unit 107, a storage unit 108, an update unit 109, a calculation unit 110, and a calculation data transmission unit 111 in addition to the units 101 to 104 described in the second embodiment.

  The setting unit 107 has a setting function for setting whether or not its own device A-2 is a representative device representing each of the protective relay devices A-1 to A-4 connected to the first transmission network NW1.

  The storage unit 108 stores protection relay device identification information that identifies a protection relay device in which a defect is detected in advance, and representative device identification information that identifies a protection relay device serving as a representative device in association with each other. In addition, the memory | storage part 108 is good also as a form which memorize | stored the circuit breaker identification information which identifies the open circuit breaker instead of the protection relay apparatus identification information which identifies the protection relay apparatus by which the defect was detected. That is, the storage unit 108 includes information indicating the operation status of the system and the device (for example, protective relay device identification information for identifying the protective relay device in which a failure is detected, and breaker identification information for identifying the opened circuit breaker. ) And the representative device identification information may be stored in association with each other.

  When a failure is detected from any of the other protective relay devices A-1, A-3, A-4 (for example, A-1) connected to the first transmission network NW1, the update unit 109 The storage unit 108 is searched based on the protective relay device identification information for identifying the protective relay device A-1 in which the failure is detected, and the setting function of the setting unit 107 is updated based on the search result. Yes.

  When the updated setting unit 107 sets that the own device A-2 is the representative device, the calculating unit 110 further includes another protection relay device (for example, A) arranged in the first transmission network NW1. -3) and the amount of electricity acquired by the acquisition unit 101 of the own device A-2 based on the amount of electricity data transmitted from the device A-2, the failure is not caused in the protective relay device A-1 in which the failure is detected. In this case, it has a calculation function for calculating the electric quantity data that is estimated to be acquired.

  When the updated setting unit 107 indicates that the own device A-2 is a representative device, the calculated data transmission unit 111 receives the electric quantity data calculated by the calculation unit 110 from the first transmission network NW1. Has a calculation data transmission function for transmitting to the protective relay device B-1 of the counterpart terminal via the second transmission network NW2 which is severely restricted.

  Next, the operation of the protective relay system configured as described above will be described.

  First, it is assumed that the representative device is the protective relay device A-2. In addition, the storage unit 108 includes protection relay device identification information for identifying the protection relay device A-1 in which a defect is detected in advance, and representative device identification information for identifying the protection relay device A-3 that is a representative device. Are stored in association with each other.

  Subsequently, it is assumed that a failure is detected in the protective relay device A-1.

  When a failure is detected from another protection relay device A-1 connected to the first transmission network NW1, the updating unit 109 of the protection relay devices A-2 and A-3 protects the failure detected. The storage unit 108 is searched based on the protection relay device identification information for identifying the relay device A-1, and the setting contents of the setting unit 107 of the own devices A-2 and A-3 are updated based on the search result. To do.

  Accordingly, the setting content of the setting unit 107 of the protection relay device A-2 is updated so that the own device A-2 is not a representative device. In addition, the setting unit 107 of the protective relay device A-3 updates the setting contents to the effect that the own device A-3 is the representative device.

  The calculation unit 110 of the protection relay device A-3, when the updated setting unit 107 is set to indicate that the own device A-3 is a representative device, is further different from the first transmission network NW1. Based on the amount of electricity data transmitted from the protective relay device A-4 and the amount of electricity data acquired by the acquisition unit 101 of the own device A-3, the protection relay device A-1 in which a failure is detected Electric quantity data estimated to have been acquired when no defect occurred is calculated.

  When the updated setting unit 107 sets that the own device A-3 is the representative device, the calculated data transmission unit 111 receives the electric quantity data calculated by the calculation unit 110 from the first transmission network NW1. Are transmitted to the protective relay device B-1 of the counterpart terminal via the second transmission network NW2 which is severely restricted.

  As described above, according to the present embodiment, the storage unit 108 is searched based on the protection relay device identification information for identifying the protection relay device A-1 in which the failure is detected, and the setting is performed based on the search result. With the configuration in which the setting content of the unit 107 is updated, the representative device can be switched in addition to the effects of the second embodiment.

  Supplementally, the function maintenance of the protective relay system can be facilitated by providing the function of automatically switching the representative device even if the operating state of the system or device changes.

<Fifth Embodiment>
Next, a protective relay system according to a fifth embodiment will be described, but before that, an outline of the present embodiment will be described.

  This embodiment is a mode in which, in the fourth embodiment, the severity of restrictions on the amount of transmission data is automatically determined from the history of transmission delay time.

  For example, it is conceivable to determine the restrictions on the transmission system based on the transmission delay time. The transmission delay time is determined by the delay time depending on the physical distance and the processing delay time of the transmission device. When there are a plurality of transmission devices, the processing delay time of the transmission device is a time obtained by accumulating the processing delay times of the individual devices.

  When using an IP network, it is possible to detect the number of hops by scanning the transmission path with an ICMP packet, so it is possible to determine how many transmission devices (routers) are present in the transmission path. Is possible. Since it is assumed that there is no router or a very small number of routers in a substation premises network, it is possible to determine that a transmission path in which a plurality of routers are interposed has a large transmission restriction.

  In addition, a network configured only by Ethernet without using IP tends to have a very short delay time for each transmission device. However, in the case of a low-speed transmission path with severe transmission restrictions, data collisions, etc. It is considered that the probability of occurrence of fluctuation (jitter) in the transmission delay time increases.

  If there is a high probability that the arrival time of the transmission frame will not be a constant interval in the measurement using the clock in the own apparatus, it can be determined that information is being exchanged via a transmission path with severe transmission restrictions. In this case, it is preferable to use the method described in the fourth embodiment to reduce the amount of data transmitted in a network with severe transmission restrictions.

  The above is the outline of the present embodiment. Then, the structure of each protection relay apparatus A-1 to A-4 is demonstrated using FIG. Since each of the protective relay devices A-1 to A-4 has the same configuration, the protective relay device A-2 will be described as a representative example here.

  The protective relay device A-2 includes a measurement unit 112, a determination unit 113, and a control unit 114 in addition to the units 101 to 111 described in the fourth embodiment.

  The measuring unit 112 has a measuring function for measuring the arrival time of the electric quantity data every time the electric quantity data arrives at the transmission unit 102 from the other protective relay devices A-1 and A-3.

  When there is a high probability that the interval between the arrival times measured by the measurement unit 112 during the predetermined period is not a constant interval, the determination unit 113 determines that the electric quantity data that arrived at the arrival time is the second transmission network NW2. It has a discriminating function for discriminating that the data has been transmitted via the.

  When it is determined that the data is transmitted via the second transmission network NW2, the control unit 114 sets the protection relay device that is the transmission source of the electrical quantity data transmitted via the second transmission network NW2. The unit 107 has a control function for controlling the transmission unit 102 so as not to transmit the electric quantity data other than the protective relay device in which the device A-2 is set as the representative device.

  Next, the operation of the protective relay system configured as described above will be described.

  First, the measuring unit 112 of each protection relay device A-i (where i = 1, 2, 3, 4) is connected to another protection relay device A-j (where j = 1, 2, 3, 3). 4, j ≠ i), every time the electric quantity data arrives at the transmission unit 102 from B-1, the arrival time of the electric quantity data is measured.

  The determination unit 113 of each protection relay device A-i arrives at the arrival time when the probability that the interval between the measured arrival times is not a constant interval is higher than a reference value during a predetermined period. It is determined that the electric quantity data is transmitted via the second transmission network NW2.

  If it is determined that the control unit 114 of each protection relay device A-i is transmitted via the second transmission network NW2, the transmission source of the electrical quantity data transmitted via the second transmission network NW2 Transmission is performed so that the electrical quantity data is not transmitted to the protection relay device B-1 other than the protection relay device A-2 in which it is set in the setting unit 107 that the own device A-2 is the representative device. The unit 102 is controlled.

  As described above, according to the present embodiment, the own device A− is connected to the setting unit 107 with respect to the protection relay device that is the transmission source of the electrical quantity data transmitted through the second transmission network NW2 in which the restriction on the transmission amount is severe. In addition to the effect of the fourth embodiment, only the representative device has a configuration in which the transmission unit 102 is controlled so that the electric quantity data is not transmitted except for the protection relay device in which 2 is set as the representative device. It is possible to perform transmission with severe restrictions.

  Supplementally, by causing the protection relay devices A-1 to A-4 to automatically detect the restrictions on the transmission path, by providing a function that appropriately reduces the amount of transmission data, a failure of the transmission equipment, etc. Even when the transmission route is switched, it is possible to quickly switch the transmission method and maintain the protection function.

  According to at least one embodiment described above, M electrical quantity data (where 2 ≦ M ≦ N) of the obtained electrical quantity data are obtained every transmission cycle tN that is N times the sampling period t. With the configuration of transmission to the protection relay device B-1 at the counterpart terminal, it is possible to reduce the amount of transmission data at all times and the number of data transmissions, thereby suppressing fluctuations in transmission delay time.

  In addition, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  A-1 to A-4, B-1 ... Protective relay device 101 ... Acquisition unit 102 ... Transmission unit 103 ... Calculation unit 104 ... Output unit 105,110 ... Calculation unit 106,111 ... Calculation data Transmission unit 107 ... Setting unit 108 108 Storage unit 109 Update unit 112 Measurement unit 113 Discrimination unit 114 Control unit

Claims (4)

A protective relay device provided at each terminal facing the power system,
Acquisition means for acquiring electric quantity data from the power system at every sampling period t;
For each transmission cycle tN that is N times the sampling cycle t, M pieces of electric quantity data (2 ≦ M ≦ N) of the electric quantity data acquired every sampling period t are protected for protection of the counterpart terminal. A transmission means for transmitting to the electric device;
With
The transmission means includes
When an accident detection signal is received from an accident detection means provided in the electric power system, at least NM pieces of electric quantity data (where N> M) that are not transmitted out of the acquired electric quantity data are converted into the above-described electric quantity data. A protective relay device comprising means for transmitting to a protective relay device of a mating terminal. A protection relay system using a plurality of protection relay devices according to claim 1 ,
Among the plurality of protective relay devices, any one of the protective relay devices connected to the first transmission network having a restriction on the transmission amount of the electrical quantity data,
When a failure is detected from any of the other protective relay devices connected to the first transmission network, the electric quantity data transmitted from the other protective relay devices connected to the first transmission network; Based on the amount of electricity acquired by the acquisition unit of the device itself, a calculation unit for calculating the amount of electricity estimated to be acquired when the failure has not occurred in the protective relay device in which the failure has been detected. When,
Further comprising: calculated data transmission means for transmitting the calculated electric quantity data to the protective relay device of the counterpart terminal via the second transmission network, which is more restrictive than the first transmission network. Protective relay system. A protection relay system using a plurality of protection relay devices according to claim 1 ,
Among the plurality of protective relay devices, each protective relay device connected to the first transmission network having a restriction on the transmission amount of the electrical quantity data is:
Setting means for setting whether the own device is a representative device representing each protection relay device connected to the first transmission network;
Storage means for storing protection relay device identification information for identifying a protection relay device in which a defect is detected in advance and representative device identification information for identifying the protection relay device serving as the representative device in association with each other;
When a failure is detected from any of the other protection relay devices connected to the first transmission network, the storage is performed based on the protection relay device identification information for identifying the protection relay device in which the failure is detected. Updating means for searching for means and updating the setting content of the setting means based on the search result;
When it is set in the updated setting means that the own device is a representative device, the electric quantity data transmitted from the other protection relay device arranged in the first transmission network, and the own device Based on the electricity quantity data obtained by the obtaining means, calculating means for calculating the electricity quantity data that is assumed to have been obtained when the failure did not occur in the protective relay device in which the failure was detected;
When it is set in the updated setting means that the own device is a representative device, the calculated electric quantity data is sent via the second transmission network, which is more restrictive than the first transmission network. A protective relay system, further comprising: calculated data transmission means for transmitting to the protective relay device of the counterpart terminal. In the protective relay system according to claim 3 ,
Each of the protective relay devices is
Each time electricity quantity data arrives from another protective relay device, a measuring means for measuring the arrival time of the electricity quantity data,
If there is a high probability that the measured arrival time intervals do not become constant intervals during a predetermined period, it is confirmed that the electric quantity data arriving at the arrival times has been transmitted via the second transmission network. Discriminating means for discriminating;
If it is determined that the data has been transmitted through the second transmission network, the setting device is connected to the protection relay device that is the transmission source of the electrical quantity data transmitted through the second transmission network. A protective relay system, further comprising: a control unit that controls the transmission unit so as not to transmit the electric quantity data other than the protective relay unit that is set to be a representative device.

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