JP4573802B2 - Digital overcurrent protection relay system - Google Patents

Description

      The present invention relates to a digital overcurrent protection relay system among protective relays that constantly monitor the amount of electric power input from the power system in order to detect and remove faults in the power system and localize the fault range. Is.

      When an accident occurs, the protective relay must remove the accident so that the power outage becomes the minimum section, and must perform protection coordination between the devices. In the conventional protection relay, the operation time characteristic curve for protection coordination is realized by selecting in advance a plurality of operation time characteristic formulas provided in the protection relay and setting parameters such as operation time magnification.

      In the protective relay realized by the data table consisting of the input current and the counter value that is added at every sampling period instead of the equation for the operating time curve, the data table has the same step size of the input current, On the other hand, a counter value is set.

Japanese Patent Laid-Open No. 6-22438 (FIG. 1 and paragraph number [0026]) Japanese Unexamined Patent Publication No. 55-26014 (FIG. 4 and its description)

      When protection coordination of protection relays is performed, depending on the operation time characteristic curves of the protection relays and fuses with which the protection relay is to be performed, there are cases in which it is not possible to set the coordination well with a plurality of operation time characteristic formulas provided in the protection relay. Also, there are cases where it is desired to realize an operating time characteristic curve with a curve that is not in the characteristic formula, for example, as a countermeasure against inrush.

      As a solution to this problem, Japanese Patent Application Laid-Open No. 2004-228561 discloses that “a curve diagram input means for inputting an arbitrary operating time characteristic curve diagram, a data conversion means for converting the curve input by the curve diagram input means into data, and this data conversion means. The protective relay includes an input means for capturing the data converted into the data and a storage means for recording the data captured by the input means.

      If the concept of Patent Document 1 is used, an optimal operating time curve for performing protection coordination is input to a curve diagram input means such as a personal computer, converted into data, and imported into a protection relay to facilitate protection coordination. Although a protection relay that can be implemented can be realized, there is no description about a specific data conversion method, and the method for realizing the data conversion means is unknown.

      Further, even if the data converted by the data conversion means is taken into the protective relay by the method described in Patent Document 1 and the protective relay is operated, the analog circuit of the protective relay, the response time of the auxiliary relay, etc. Therefore, an error occurs in the actual operation time.

      The realization of the operation time curve by data is described in Patent Document 2, but in this method, the step size of the input current is constant and the step size such as a large current region where there is almost no change in the operation time. Since there is a large amount of data even in a portion that does not need to be made fine, there is a problem that the required memory capacity increases.

The present invention has been made in view of the above circumstances, and its main purpose is to realize a digital overcurrent protection relay system that operates with an arbitrarily drawn operation time curve in order to facilitate protection coordination. Furthermore, it is in the realization of a digital overcurrent protection relay system with high operation time accuracy .
Further, an object of another aspect of the present invention, can save a memory capacity to store the data, it is to provide a digital overcurrent protection relay system cost can be reduced.

The digital overcurrent protection relay system according to the present invention comprises a curve diagram input means for inputting an operation time characteristic curve diagram for determining an operation characteristic of the overcurrent protection relay, and a curve inputted by the curve diagram input means is a magnitude of a current. A digital overcurrent protection relay system comprising data converting means for converting to data equivalent to operating time for the data, and storage means for recording data converted into data by the data converting means, the operating time corresponding to the magnitude of the current as corresponding data, data obtained by converting the counter value corresponding to the operation time of each magnitude of the current determined by the operation time characteristic curve diagram is recorded in the storage unit, the recorded counter value, measured against overcurrent The counter value corresponding to the actual operating time of the protected relay is corrected, and the corrected counter value is recorded in the storage means. , From the corrected counter value in the storage means is recorded data, it retrieves the counter value corresponding to the input overcurrent, counts the corrected counter value recorded in the storage means corresponding to the input overcurrent Thus, the operation is performed for a predetermined operation time with respect to the input overcurrent.

According to the present invention, a curve diagram input means for inputting an operation time characteristic curve diagram for determining an operation characteristic of an overcurrent protection relay, and a curve input by the curve diagram input means is converted into an operation time equivalent data for a current magnitude. A digital overcurrent protection relay system comprising data conversion means and storage means for recording data converted into data by the data conversion means, wherein the operation time characteristic is the operation time equivalent data for the magnitude of the current. data converted to the counter value corresponding to the operation time of each magnitude of the current determined by the curve diagram are recorded in the storage unit, the recorded counter value, the protective relays actual operation time measured for overcurrent is corrected to the corresponding counter value, the corrected counter value is recorded in the storage unit, which is the correction in the storage unit counter From the data but recorded, input to search a counter value corresponding to the overcurrent, by counting the corrected counter value recorded in the storage means corresponding to the input overcurrent at a predetermined operating time for the input overcurrent Because it operates, it is possible to realize a digital overcurrent protection relay system that operates with an operation time curve arbitrarily drawn to facilitate protection coordination, by realizing a specific means of data conversion , and more accurate operation time the effect of that Ru can achieve high digital overcurrent protection relay system with.

Reference Example 1
Hereinafter , an example of an improved digital overcurrent protection relay system born in the process leading to the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing an example of a system configuration, FIG. 2 is a diagram showing an example of an operation time curve input from a curve diagram input means, and FIG. 3 is a diagram showing examples of restrictions when inputting from a curve diagram input means. 4 is an explanatory diagram of a data conversion method when data is generated from an operation time curve, and FIG. 5 is a conceptual diagram showing an example when a personal computer is used as an example of a curve diagram input means. In addition, in each figure, the same code | symbol shows the same part.

FIG. 1 is the same system configuration diagram as FIG. 1 described in Patent Document 1. Like FIG. 1 described in Patent Document 1, the digital overcurrent protection relay system of Reference Example 1 is an R-phase rectification / smoothing circuit. R-phase analog filter circuit 21 having a T-phase analog filter circuit 22 having a T-phase rectification / smoothing circuit, etc., a microcomputer (hereinafter abbreviated as “microcomputer”) 23 which is a calculation function part of a relay, The circuit 24-26, the output circuit 27, the display 28, the A / D conversion circuit 33, the curve input means 60, the data conversion means 61, the input means 62, and the storage means 63 are configured. . The digital protective relay 6 includes an R-phase analog filter circuit 21 having an R-phase rectification / smoothing circuit, a T-phase analog filter circuit 22 having a T-phase rectification / smoothing circuit, and a microcomputer (relay calculation function unit). (Hereinafter abbreviated as “microcomputer”) 23, an establishment circuit 24-26, an output circuit 27, a display 28, an A / D conversion circuit 33, an input means 62, and a storage means 63. . It may be provided in the curve input means 60, the data converting means 61 and the digital protection relay 6, or may be connected to the digital protection relay 6 via a connection cable or a network.

An R-phase analog filter circuit 21 having an R-phase rectification / smoothing circuit, a T-phase analog filter circuit 22 having a T-phase rectification / smoothing circuit, etc., and a microcomputer (hereinafter abbreviated as “microcomputer”) as a calculation function unit of a relay 23, the establishment circuit 24-26, the output circuit 27, the display 28, the A / D conversion circuit 33, the curve input means 60, the input means 62, the storage means 63, and the functions of the digital protection relay 6 are the same as in Patent Document 1. Therefore, the description thereof is omitted.
FIG. 1 shows an example of a system configuration to which the present invention is applied. For example, the present invention can be applied only to an R-phase, S-phase, and T-phase three-phase input type overcurrent relay. It can also be applied to phase input type overcurrent relays.

In this reference example , a specific method of the data converting means 61 will be described. With respect to the curve diagram input means 60, an operation time curve is drawn as shown in FIG. The horizontal axis of the operating time curve is the input current (the ratio of the input current to the operating current set value), and the vertical axis represents the operating time. The constraint conditions here are as follows.
1. The operating current and the operating time are within the specified range. An extremely long operating time or a time shorter than the minimum necessary time for operating the relay cannot be set. Also, it cannot be set where the ratio of the input current to the operating current set value is very large, and the operating time is fixed at a current above a certain level (usually 2000%). However, even with these restrictions, it can be set sufficiently in normal protection coordination.
2. A curve having a plurality of operation times as shown in FIG. 3 cannot be set for a certain input current.
3. The operating time curve may be a straight line, but it must be continuous.

For the operation time curve drawn by the curve diagram input means 60, the data conversion means 61 creates a data table in the following manner.
(1) Based on the drawn operation time curve, the operation time for each current value is obtained at certain intervals.
Example: Input current 200% → Operating time 0.20s
202% → Operating time 0.18s
204% → Operation time 0.17s, etc. (2) As shown in Fig. 4, calculate the data (counter value) as shown below from each current value and operation time.
Determine the maximum counter value (assuming A) → When this counter value is reached, the operation cycle in the protective relay operation protective relay is ST.
→ Example: In case of a protective relay that performs calculations at a rated electrical frequency of 30 ° and a frequency of 30 °
ST = 1 / (50 × 12)
The input current and the operation time are set to the operation time T with respect to the current I.
Calculate K such that K = A x ST / T.
→ Add K for each calculation, and set K (counter value) so that it becomes A after T.
Even if the input current changes before the operation of the protective relay, it operates in an appropriate operating time according to the change.
The above counter value (K) is calculated for each input current value in the input current range of the operating time curve, and a K data table is created. Since complicated processing is not required in the calculation process, the data conversion means can be provided in the protective relay itself, for example, without being a personal computer.

      The data table created by the data converting means 61 is taken into the protective relay through the data input means 62 of the protective relay. The protective relay itself can be provided with a curve diagram input means and a data conversion means. In this case, it is not necessary to take in data.

      The protection relay that has taken in the data table created by the data conversion means stores the data table in a nonvolatile memory (storage means 63) built in the protection relay.

The protective relay operates as follows.
The ratio of the input current to the operating current set value is calculated every calculation cycle.
When the ratio of the input current exceeds 1, the input current is compared with the data table, and the counter value K corresponding to the input current is searched. When the counter value K is determined, the value is added for each calculation. If the counter value K exceeds the maximum counter value A, the protective relay is activated.

      An example of the curve diagram input means and data conversion means is a personal computer. A personal computer tool that can freely draw an operating time curve on the screen and creates a computer that calculates data from the operating time curve using a personal computer process. Connect the communication port such as RS232C of the personal computer and the protective relay as shown in Fig. 5, and send the data of the personal computer to the protective relay. As a method of the curve diagram input means and the data conversion means, a method other than a personal computer may be used, and the function can be incorporated in the protective relay itself.

As described above, the improved digital overcurrent protection relay system born in the process of the present invention has a curve diagram input described in Patent Document 1 in order to operate the protection relay with an arbitrarily set operation time curve. Means 60 and data converting means 61, the data converting means being a digital overcurrent protection relay system capable of creating data by a simple conversion formula; in other words, an operation for determining the operating characteristics of the overcurrent protection relay A curve diagram input means 60 for inputting a time characteristic curve diagram, a data converting means 61 for converting the curve input by the curve diagram input means into data corresponding to the operating time for the current magnitude, and data conversion by this data converting means A digital overcurrent protection relay system comprising a storage means 63 for recording the recorded data, wherein the operation time corresponding to the magnitude of the current As a data, the data converted into a counter value corresponding to the operating time for each current magnitude determined by the operating time characteristic curve diagram is recorded in the storage means, and the input overcurrent is calculated from the data recorded in the storage means. Is a digital overcurrent protection relay system that operates in a predetermined operation time with respect to the input overcurrent by searching for the counter value corresponding to the input overcurrent and counting the recorded counter value in the storage means corresponding to the input overcurrent. Therefore, a digital overcurrent protection relay system that operates with an arbitrarily drawn operation time curve to facilitate protection coordination can be realized by realizing a specific means of data conversion.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to FIGS. FIG. 6 is a block diagram showing an example of the system configuration, FIG. 7 is a flowchart showing an example of how to correct the data table, and FIG. 8 is a diagram showing an example of the method of correcting the data table outside the operation time measurement. 1 to 8, the same or corresponding parts are denoted by the same reference numerals.

The first embodiment includes an operation time input unit 101 and a data correction unit 103. The data table created by the first embodiment is taken into the protective relay, and a protective relay that operates according to an arbitrary operation time curve is manufactured. When current is passed through this protective relay and the actual operating time is measured, the operating time is often slightly different from the operating time curve drawn on the curve diagram input means. This is because there is a response time of the analog circuit of the protective relay and the auxiliary relay, a plurality of sampling data is necessary for the digital calculation, and it takes time for the change of the data to be reflected in the digital calculation result.

      In order to reduce the error in the operation time, the operation time input unit 101 and the data correction unit 103 correct data. For the protective relay incorporating the data table created according to the first embodiment, the input current is changed and the operating time at that time is measured. The input current is measured only for a few points, not all the input current patterns that make up the data table. The control point defined by the protection relay standard is one standard for the measurement point, but the accuracy can be improved by measuring in detail.

      The measured input current value and operation time are input from the operation time input means 101. The data correction unit 103 corrects data in the following procedure from the input current value and the operation time (actual value) input and the operation time curve (theoretical value) input from the curve diagram input unit, and the data table Recreate.

With respect to the operating time curve, the operating time at a certain input current I1 is T1. In the first embodiment, the counter value at the input current I1 in the data table created from the curve diagram input means and the data conversion means is K1. In addition, when the current I1 is actually input to the protective relay that fetches the data table and the operation time is measured, the operation time is T′1. Further, T′1−T1 = ΔT1.
K1 was added for each calculation, and K1 was set to be A after T1, but in order to correct the operating time, K′1 was added for each calculation, and A after T1−ΔT1 Thus, it is necessary to determine K′1.
K′1 = A × ST / (T1−ΔT1) = A × ST / (2 × T1−T′1)
T1 and A are values when the data table is created in Reference Example 1, and T′1 is a measured value.
By replacing the data table created in Reference Example 1 with K′1 as shown in FIG. 7, it is possible to obtain a protective relay with higher operating time accuracy.

      It is unrealistic to measure and correct the operating time for all input current values on the data table, and only the counter value is corrected. For the other data, the correction rate of the counter value that has been corrected is calculated, and the correction rate is used to correct the data for which the operating time is not measured.

Assume that the counter value is corrected from K1 to K′1 for the data of the input current I1 in the data table. Similarly, it is assumed that the counter value is corrected from K2 to K′2 for the data of the input current I2. Assuming that the input current for which the operating time is not measured is I3, if I1 <I3 <I2 is satisfied, correction is performed by the following method.
(1) K′1 / K1 = α1 and K′2 / K2 = α2 (2) α3 = {(α2−α1) / (I2−I1)} × I3 + {(Α1 × I2−α2 × I1) / (I2−I1)}
As shown in FIG. 8, in the straight line connecting (I1, α1) and (I2, α2), α at I3 is derived.
(3) The original counter value K3 in I3 is corrected to α3 × K3 = K′3.
(4) Similarly, correction is performed on other uncorrected data.
(5) If there is no measurement data for the operating time corresponding to I1 or I2 where I1 <I3 <I2,
In the case of I1 <I3, α3 = α1 is simply set, and K3 × α1 = K′3.
When I3 <I2, simply α3 = α2 and K3 × α2 = K′3.

      As described above, the data correction means 103 corrects all the counter value data tables and imports them again into the protective relay. Since the data table considering the response time of the analog circuit and the auxiliary relay can be created, the protective relay can be operated in an operation time closer to the drawn operation curve.

In the first embodiment, as described above, the operation of the protective relay is performed for the protective relay configured to operate according to the arbitrarily set operating time curve by taking in the data created from the arbitrarily set operating time curve diagram. It is a digital overcurrent protection relay system that measures the time, inputs the operation time data, corrects the data, takes the corrected data back into the protection relay, and reduces the error in the operation time of the protection relay. In other words, in the digital overcurrent protection relay system, the actual operating time of the protective relay against overcurrent is measured, and the counter value corrected to the counter value corresponding to the actual operating time is recorded in the storage means. Therefore, it is possible to increase the accuracy of data by the correcting means and realize a digital overcurrent protection relay system with a small operating time error.

Embodiment 2 FIG.
The second embodiment of the present invention will be described below with reference to FIG. 9 showing another example of the system configuration in a block diagram.

In the second embodiment, in addition to the curve diagram input means 60 and the data conversion means 61, a data conversion means selection unit 102 is provided. It is assumed that there are a plurality of data conversion means 61, 61-1, 61-2,..., And operation time input means 101 and data correction means 103 are provided as necessary.
In Reference Example 1 and Embodiment 1 , the data table is uniquely created by the data converting means 61. At this time, the step size of the input current in the data table is constant, and even in a region where the slope of the operating current curve is steep and the change in the counter value of the data table is large, the slope of the operating current curve is gentle and the data table Even in a region where the counter values continue to be the same value, the data amount is the same for a certain input current range, and the memory capacity (storage means 63) required by the protective relay is the same.

      However, depending on the hardware configuration of the protective relay, there are cases where the memory capacity must be saved. Also, saving memory capacity leads to cost reduction of the protective relay itself.

      For cases where it is desired to change the data conversion means, such as when the memory capacity is limited, a data conversion means selection unit 102 is added to protect the relay from the plurality of data conversion means 61-1, 61-2,. By making it possible to select the optimum data conversion means from the characteristics of the memory capacity and the operating curve, it is possible to save the memory capacity, and in turn, it is possible to reduce the cost of the digital protection relay and the digital protection relay system itself.

Second embodiment, as described above, when creating the data from the operation time curve arbitrarily set, select that data creation means may create a memory capacity of the protective relays, it was in the required accuracy data In other words, a plurality of data conversion means having different data amounts are provided, and the plurality of data conversion means are selected by the data conversion means selection section, and the selected data conversion is performed. A digital overcurrent protection relay system in which data converted into data is recorded in the storage means is provided. Therefore, it is possible to save the memory capacity, and as a result, it is possible to reduce the cost of the digital protection relay and the digital protection relay system itself.

Embodiment 3 FIG.
The third embodiment of the present invention will be described below with reference to FIG. 10 showing an example of a data capacity reduction method.

      In general, in the operation time curve, the larger the input current, the shorter the operation time, and the larger the input current, the gentler the curve slope. If the step size of the input current in the data table is constant, the change in the counter value at each input current is small in the region where the slope of the operation curve is gentle. In such an area, even if the step size of the input current in the data table is increased, the counter value hardly changes. Therefore, the error in the operation time is small even in the input current not in the data table.

Therefore, in the region where the slope of the operation curve is gentle, the step size of the input current in the data table can be increased.
In the third embodiment, as illustrated in FIG. 10, the data table is created so that the step size of the input current in the data table increases as the input current increases. For example, as shown in FIG. 10, in the region where the input current is 200%, the step size of the input current is 200%, 210%, 220%,... In the region, the step size of the input current is 1500%, 1550%, 1600%,.
As a result, the size of the data table can be reduced, the capacity of the internal memory (storage means 63) of the digital protection relay 6 can be reduced, and the cost can be reduced. Data table creation guidelines include, for example, making the input current and step size proportional to each other, or increasing the step size exponentially, so that the data table can be created without complicated processing. Can also be incorporated into the digital protection relay 6.

In the third embodiment, as described above, with respect to data created from an arbitrarily set operating time curve, the step size of the input current is increased in a region where the change amount of the operating time with respect to the input current is small, such as a large current region. Thus, the capacity of the data to be created can be reduced. In other words, each of a plurality of currents with a certain step size is converted into the counter value corresponding to the operation time, and the operation time characteristics The region where the change amount of the operating time in the curve is small is the digital overcurrent protection relay system in which the step size is increased. Accordingly, the size of the data table can be reduced, the capacity of the internal memory (storage means 63) of the digital protection relay 6 can be reduced, and the cost can be reduced.

Embodiment 4 FIG.
The fourth embodiment of the present invention will be described below with reference to FIG. 11 showing an example of a data capacity reduction method.

In the above-described third embodiment, the step size is determined only by the magnitude of the input current, but the actual operation time curve has various changes in the slope. In the region where the input current is small, the slope becomes gradual, and even if the input current increases further, the operation time hardly changes (see (a) in FIG. 11), or the operation time even if the input current increases. There is a case where the change of (see (b) in FIG. 11) is large. At this time, in the data conversion according to the third embodiment, there is a problem that an error increases with a certain input current. Therefore, in the fourth embodiment, data is generated based on the following guidelines. .

      The operation time at an arbitrary input current I1 is T1, and the operation time at an arbitrary input current I2 is T2. Here, the step size of the input current is determined so that the area of the triangle formed by (I1, T1), (I2, T2), (I1, T2) is always constant. A table of input current and counter value is created with this step size. Where the change in operating time is large, the step size of the input current can be reduced, and where the change in operating time is small, the step size of the input current can be increased. As a result, it is possible to reduce the size of the data table and reduce the capacity of the internal memory (storage means 63) of the digital protection relay 6 while maintaining an error in the input current other than the data table.

As described above, the fourth embodiment creates data by setting the step size of the input current so that the area created by the operation time curve is equal for the data created from the arbitrarily set operation time curve. Thus, it is possible to reduce the volume of data created while ensuring accuracy, in other words, the areas between the plurality of currents at the certain step size and the operating time characteristic curve are substantially equal. This is a digital overcurrent protection relay system.

Embodiment 5 FIG.
The fifth embodiment of the present invention will be described below with reference to FIG. 12, which is a block diagram showing still another example of the system configuration.

In the fifth embodiment, operation curve selection means 104 is provided for selecting a data table to be applied. A data table is created from an arbitrary operation time curve by the method described in the first to fifth embodiments. A plurality of data tables can be stored in the storage means 63 of the digital protection relay 6 so that an appropriate operation curve can be selected depending on the system or other equipment in which the digital protection relay is introduced.

      The operation time curve to be selected is based on a characteristic table defined by a standard or the like, even if it is based on a data table created from an arbitrary operation time curve input by the curve diagram input means 60. May be stored as In addition, since an arbitrarily drawn operation time curve is difficult to understand unless the curve is actually confirmed, it is preferable to provide means for displaying a graph of the data table.

As described above, in the fifth embodiment, a plurality of data is acquired and stored for realizing the protective relay that operates with an arbitrarily set operating time curve, and the operation is performed only by changing the setting. The time curve can be switched, in other words, operation time equivalent data corresponding to each of a plurality of operation time characteristic curves having different operation times is stored in the storage means, and the plurality of operation time characteristics are stored. This is a digital overcurrent protection relay system in which operation time equivalent data corresponding to each of the curves is selectively used.

Embodiment 6 FIG.
A sixth embodiment of the present invention will be described below with reference to FIG. 13 showing an example of combining operating time characteristic curves.

      When setting an operation time curve arbitrarily, it is often desired not only to draw freely but also to set the entire curve or a part of the curve with a standard operation characteristic formula as in the standard. In addition, when the characteristic formulas of other devices to be protected and coordinated are known, there are cases in which setting is easier by selecting from the standard operating characteristic formulas than drawing freely.

      In the curve input means 60, a characteristic equation prepared in advance is selected for a function that allows an operation curve to be freely input, so that the entire curve or a part thereof can be combined. FIG. 13 shows an example in which a part of the curve can be realized according to the characteristic equation. A data table is created from the combined operation time curve and is taken into the digital protection relay 6.

As described above, in the sixth embodiment, when an operation time curve is arbitrarily set, the operation time curve is set not only by a freely drawn curve but also by a combination with an operation time curve formula prepared in advance. In other words, the operation time characteristic curve is configured by combining a plurality of operation time characteristic curves, and the operation is configured by combining the plurality of operation time characteristic curves. A digital overcurrent protection relay system that converts a time characteristic curve into data corresponding to an operation time corresponding to the magnitude of current and records the data in the storage means, and in other words, one of the plurality of operation time characteristic curves. The operating time characteristic curve is an operating time characteristic curve arbitrarily drawn by the curve diagram input means, and another operating time characteristic curve of the plurality of operating time characteristic curves is prepared in advance. A digital overcurrent protection relay system is operational time characteristic curve by the operation time curve equation is.

It is a figure which shows the example of the improved digital overcurrent protection relay system born in the process leading to this invention , and is a block diagram which shows an example of a system structure. It is a figure which shows the example of the improved digital overcurrent protection relay system born in the process leading to this invention, and is a figure which shows an example of the operation time curve input from a curve figure input means. It is a figure which shows the example of the improved digital overcurrent protection relay system born in the process leading to this invention, and is a figure which shows the example of the restriction | limiting matter at the time of inputting from a curve figure input means. It is a figure which shows the example of the improved digital overcurrent protection relay system born in the process leading to this invention , and is explanatory drawing of the data-ized method at the time of data-forming from an operation time curve. It is a figure which shows the example of the improved digital overcurrent protection relay system born in the process leading to this invention , and is a conceptual diagram which shows an example when a personal computer is used as an example of a curve figure input means. It is a figure which shows Embodiment 1 of this invention, and is a block diagram which shows an example of a system configuration | structure. It is a figure which shows Embodiment 1 of this invention, and is a figure which shows an example of the correction method of a data table with a flowchart. It is a figure which shows Embodiment 1 of this invention, and is a figure which shows the example of the correction method of the data table outside operation time measurement. It is a figure which shows Embodiment 2 of this invention, and is a block diagram which shows another example of a system configuration. It is a figure which shows Embodiment 3 of this invention, and is a figure which shows the example of the data capacity reduction method. It is a figure which shows Embodiment 4 of this invention, and is a figure which shows the example of the data capacity reduction method. It is a figure which shows Embodiment 5 of this invention, and is a block diagram which shows another example of a system configuration. It is a figure which shows Embodiment 6 of this invention, and is a figure which shows the example which performs the combination of an operating time characteristic curve.

6 Digital protective relay,
21 R-phase analog filter circuit,
22 T-phase analog filter circuit,
23 Microcomputer (microcomputer),
24-26 established circuit,
27 output circuit,
28 Display,
33 A / D conversion circuit,
60 Curve diagram input means,
61 Data conversion means,
62 input means,
63 storage means,
61-1, 61-2 data conversion means,
101 operation time input means,
102 data conversion means selection unit,
103 data correction means,
104 Operation curve selection means.

Claims (7)

Curve diagram input means for inputting an operation time characteristic curve diagram for determining the operation characteristics of the overcurrent protection relay, and data conversion means for converting the curve input by the curve diagram input means into operation time equivalent data for the magnitude of the current; A digital overcurrent protection relay system comprising a storage means for recording data converted into data by the data conversion means, and is determined by the operating time characteristic curve diagram as operating time equivalent data for the magnitude of the current data converted to the counter value corresponding to the operation time of each magnitude of the current is recorded in the storage unit, the recorded counter value, measured corresponding to protection relays actual operation time counter value for overcurrent is corrected to, the corrected counter value is recorded in the storage unit, the corrected counter value in the storage means is recorded From the data, it searches the counter value corresponding to the input overcurrent, over digital operates in a predetermined operation time by counting the corrected counter value recorded in the storage means corresponding to the input over-current to the input overcurrent Current protection relay system. 2. The digital overcurrent protection relay system according to claim 1, wherein a plurality of data conversion means having different data amounts are provided, and the plurality of data conversion means are selected by the data conversion means selection unit, and the selected data conversion means is selected. A digital overcurrent protection relay system characterized in that data converted into data by the data conversion means is recorded in the storage means. 3. The digital overcurrent protection relay system according to claim 1 or 2, wherein each of a plurality of currents in a certain step size is converted into the counter value corresponding to the operation time, and the operation in the operation time characteristic curve. The digital overcurrent protection relay system, wherein the step size is increased for a region where the amount of change in time is small. 4. The digital overcurrent protection relay system according to claim 3 , wherein each of the areas between the plurality of currents in the certain step size and the operating time characteristic curve is made substantially equal. Protective relay system. A digital overcurrent protective relay system according to any one of claims 1 to 4, the operation time corresponding data corresponding to each of a plurality of operating time characteristic curve of the different operating times is stored in the storage means A digital overcurrent protection relay system, wherein operation time equivalent data corresponding to each of the plurality of operation time characteristic curves is selectively used. 6. The digital overcurrent protection relay system according to claim 5 , wherein the operating time characteristic curve is configured by combining a plurality of operating time characteristic curves, and the operating time characteristic curve configured by combining the plurality of operating time characteristic curves is defined as a current. A digital overcurrent protection relay system, wherein the data is converted into operation time equivalent data and recorded in the storage means. 7. The digital overcurrent protection relay system according to claim 6 , wherein one of the plurality of operation time characteristic curves is an operation time characteristic curve arbitrarily drawn by the curve diagram input means, The digital overcurrent protection relay system, wherein the other operating time characteristic curve among the plurality of operating time characteristic curves is an operating time characteristic curve based on an operating time curve formula prepared in advance.

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