JP2986165B2 - Control / protection system - Google Patents

Description

The present invention relates to various control systems and protection systems such as power systems, and more particularly, to a settling method capable of changing coefficient values in an online state. Further, the present invention relates to a control / protection system to which the setting method is applied.

[Prior Art] Generally, in a control or protection system,
The computer constituting the system performs an operation for control or protection on the input information by using a coefficient (parameter) value given in advance. In such a system, the coefficient value may need to be changed due to a change in the control or protection target.

It is preferable that the change of the coefficient value can be performed online, that is, without stopping the operation of the computer, depending on the system.

2. Description of the Related Art Conventionally, as a settling method capable of changing a coefficient value online, there is a method described in Japanese Patent Application Laid-Open No. 55-138106.

The technology described therein is based on non-volatile memory,
A second buffer memory, wherein when changing the coefficient, the transfer of the coefficient value from the nonvolatile memory to the first buffer memory is prohibited, and the coefficient value is stored in the first buffer memory. The arithmetic operation of the computer is executed, during which the coefficient value is set in the nonvolatile memory, the set coefficient value is stored in the second buffer memory, and the validity of the coefficient value transferred to the second buffer memory is determined. After the property is checked by a computer, the new coefficient value set in the non-volatile memory is input to the computer via the first buffer memory to perform a control operation.

[Problem to be Solved by the Invention] The above-described conventional technology is excellent in that the setting of the coefficient value can be changed online.

However, in this conventional technique, no consideration is given to the case where the power is cut off during the operation of changing the coefficient value. Therefore, if the power is turned off, there is a problem that the calculation of the computer is performed by using the values up to the middle of the coefficient change, regardless of whether the set value is checked by the operator. In such a case, there is a danger that an error occurs in the control or the protection operation, which leads to the occurrence of an accident.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a settling method that can execute a computer operation with a value before a coefficient change even when power is cut off during a coefficient setting change operation.

Another object of the present invention is to provide a control or protection system that can restart operation without fear of malfunction when restarting even if power is cut off by such a setting method. is there.

Means for Solving the Problems The object of the present invention is to provide a control or protection system in which a plurality of electrically erasable and rewritable nonvolatile memories are used for setting a coefficient of a system, Is written for the plurality of memories.
This is achieved by performing the first and second steps in two or more steps.

Further, in the settling method in the control or protection system, a plurality of electrically erasable and rewritable nonvolatile memories are used for setting the coefficient of the system, and writing of a new coefficient to the memory is performed by the plurality of memories. While holding the previous coefficient in one of the memories, the other memory of the plurality of memories is used, and after the writing to the other memory is completed, the new coefficient is stored in the one memory. It is also achieved by writing.

Another object of the present invention is to provide a coefficient setting panel for displaying a setting state while receiving a coefficient setting from the outside, and a first and a second for storing and holding a coefficient set in the coefficient setting panel.
A non-volatile memory, a buffer memory for storing coefficient values stored in the second non-volatile memory, a coefficient value stored in the buffer memory, and information input from a protection or control target. At least a computer that executes an operation for protection or control and controls the system, and stores the coefficients set on the coefficient setting panel in the order of a first nonvolatile memory and a second nonvolatile memory. By performing the processing in two stages, and after setting a new coefficient in the second nonvolatile memory, the content of the buffer memory is rewritten with the coefficient stored in the second nonvolatile memory. Achieved.

Also, writing of a new coefficient is performed for the first nonvolatile memory while holding the previous coefficient in the second nonvolatile memory, and after the writing to the first nonvolatile memory is completed. A function for writing a new coefficient to the second nonvolatile memory, and when the power is cut off during the coefficient changing operation, the function is stored in the second nonvolatile memory when the system is restarted. This is achieved by a configuration in which the system is operated using the coefficient values before the change.

The control or protection system configured according to the present invention, when writing a new coefficient into the second nonvolatile memory, or after writing the new coefficient, stores the content of the second nonvolatile memory into the first nonvolatile memory. It is preferable to have a function of collating with the contents stored in the memory and displaying the collation result on the coefficient setting panel.

It is also preferable to have a function of displaying a corresponding message on the coefficient setting panel when the system is turned off when the coefficient is set and when the system is restarted.

[Operation] In the present invention, at least two nonvolatile memories are provided, and when a coefficient is newly set, first, a new coefficient is written to the first nonvolatile memory. Then, after the writing of the coefficient value is confirmed, a new coefficient value is written to the second nonvolatile memory.

As described above, since the coefficient is set in at least two stages, even if the power is cut off while the coefficient is being written to the first nonvolatile memory, the change is not stored in the second nonvolatile memory. Since the previous coefficient value is stored, the operation can be restarted by using the coefficient value before change stored in the second nonvolatile memory when the system is started up.

Therefore, according to the present invention, since the operation using the uncertain coefficient in the middle of the change is not performed, the malfunction of the system can be prevented, and the setting can be performed with high reliability.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of an embodiment of a power protection system to which the settling method of the present invention is applied.

The protection system according to the present embodiment includes a coefficient setting panel 10 for performing a coefficient setting operation from the outside, electrically erasable and rewritable nonvolatile memories 20 and 21 for storing and holding set coefficient values, and the memory. Buffer memories 30 and 40 for holding coefficient values transferred from 20, 21; a computer 60 for executing a protection relay operation based on input information using coefficient values stored in buffer memory 30; When an accident is detected, an output circuit 70 that outputs a shut-off command in response to the detection, and an input circuit 50 that periodically inputs the system information I sampled at regular time intervals to a computer. You.

In this embodiment, the nonvolatile memories 20 and 21 are E ² PRO
M is used. Of course, the present invention is not limited to this, and other memories may be used as long as they can be erased and rewritten. For example, EPROM, EAROM and the like can be mentioned.

The non-volatile memory 20 is connected to the coefficient setting panel 10, stores and holds the set coefficient, and is connected to the buffer memory 40 so that the stored coefficient value can be transferred to the buffer memory. You.

On the other hand, the non-volatile memory 21 is connected to the buffer memory 40 and can transfer coefficient values to and from the buffer memory 40, and can be connected to the buffer memory 30 to transfer stored coefficient values. It is configured as follows.

Each of the buffer memories 30 and 40 is constituted by, for example, a RAM (random access memory), and is connected to the computer 60 so that the computer 60 can read out the stored contents.

The computer 60 includes a central processing unit (CPU) 61 that executes protection relay arithmetic and system control, and a RO that stores a program that defines an accident detection algorithm for performing protection relay arithmetic, a system control program, and the like.
It includes at least an M62 and a RAM 63 for storing input data and operation results, and executes an accident detection operation.

FIG. 2 conceptually shows an example of the configuration of a coefficient setting panel suitably used in the above embodiment.

The coefficient setting panel of the present embodiment has a display 1 for displaying coefficient values.
A coefficient setting switch 2 for setting a coefficient, a coefficient writing switch 3 for writing the value of the coefficient setting switch 2 to the non-volatile memory 20, and a coefficient selection switch (which functions as a relay selection switch in the case of a protection relay). ) 4
A coefficient change command switch 5, a coefficient check command switch 6 for checking these values after the coefficient is changed, a coefficient changing display 7 for displaying that the coefficient is being changed, and a normal coefficient change. A normal setting display 8 for displaying
An abnormality setting display 9 for displaying that the coefficient change value is abnormal is provided.

The coefficient selection switch 4 includes element coefficient selection switches 41 to 45
have. In this embodiment, five switches are used. However, a required number of switches may be set according to the needs of the system.

The coefficient setting panel 10 mainly includes a protection relay device that protects these transmission lines and the like when there is an accident in a transmission line, a transformer, a bus, etc. Used for control devices such as gasifiers. The present invention is not limited to this, and the present invention can be applied to a system in which a coefficient is changed with respect to an operating state of a control computer such as a steel or a railway.

 Next, the operation of the present embodiment will be described.

Prior to the description of the operation of this embodiment, the normal operation of the protection relay will be described with reference to FIG.

The present system periodically inputs the system information I sampled at regular time intervals to the computer 60 through an input circuit.
The setting value stored in the non-volatile memory 21 that stores the coefficient value (the setting value of the element relay in the case of the protection relay) is input through the buffer memory 30 while being input through the buffer memory 30. And every time you take in the input information,
Computer 60 performs the operation according to the accident detection algorithm.
Apply in.

The computer 60 performs a process of comparing the amount derived by the calculation with the input coefficient value, and issues a cutoff command via the output circuit 70 when it is determined that an accident has occurred.

This arithmetic processing is repeatedly performed on the input data at each sample.

Next, a specific description of the operation of the present embodiment will be given in the first section.
This will be described with reference to FIGS. FIG. 3 is an operation flowchart of this embodiment.

First, the coefficient setting panel 10 receives a coefficient change command from an operator (step 100). That is, the coefficient change command switch 5 shown in FIG.
Is turned on, the coefficient changing indicator 7 shown in FIG. Writing the coefficient value from the nonvolatile memory 21 to the data buffer 30 shown in FIG.
Stop by signal line A.

The computer 60 intermittently executes the protection relay calculation process using the coefficient value frozen in the buffer memory 30.

Next, in the relay selection switch 4 shown in FIG.
Accept the selection of the element relay for setting change (step
101). That is, the selection is accepted when the corresponding selection switch of the setting change relay is operated and turned on by the operator.

The on state of this switch is sent to the computer 60 via the signal line C, and the CPU 61 reads out the coefficient value corresponding to the switch from the buffer memory 30 and sends it to the coefficient setting board 10 via the signal line D. Then, in the coefficient setting panel 10, the contents thereof, that is, the coefficient value before the change (current) of the relay is displayed on the display 1 shown in FIG.

In the following step 102, a coefficient value setting from the operator to the coefficient setting switch 2 shown in FIG. 2 is received. When the operator turns on the coefficient writing switch 3 shown in FIG.
Is written to the corresponding address of the nonvolatile memory 20 via the signal line B.

At the same time, this is notified to the computer 60 via the signal line C. Then, the coefficient value written in the nonvolatile memory 20 is automatically stored in the corresponding address of the buffer memory 40. In addition, the CPU 61
The content written to 0, that is, the content written to the non-volatile memory 20 is sent to the coefficient setting panel 10 via the signal line D and displayed on the display 1.

In step 103, the CPU 61 uses the idle time of the task, checks the time at which the changed coefficient value was written to the buffer memory 40, inputs this value, and checks this value, that is, the deviation. Check the performance (for example, for the protection relay, check the set value range). further,
The result is displayed on the indicators 8 and 9 via the signal line D in FIG. That is, if the check result is normal, the normal setting display 8 is turned on, and if the check result is abnormal, the abnormal setting display 9 is turned on.

The operator checks the result and the value of the display 1 in FIG. 2, and if the result is normal, shifts to the next coefficient change. In the case of an abnormality, the process returns to step 102 in FIG. 3, and the same processing as above is executed again.

Hereinafter, exactly the same processing is repeated by the number of coefficient changes. If it is determined in step 104 that all the planned coefficient changes have been completed, the process proceeds to step 105.

In step 105, a confirmation operation from the operator who has visually recognized the coefficient value displayed on the display 1 is accepted. That is, when the coefficient confirmation switch 6 is turned on by the operator, the fact is notified to the computer 60 via the signal line C.

At this stage, since all the changed coefficient (settling) values should have been input to the buffer memory 40 in FIG. 1, the computer 60 uses the idle time of the task and inputs all these values. Then, for example, a check is made of the magnitude relation between the coefficients. In the case of a protection relay, as shown in the characteristic example of the distance relay in FIG. 4, the relationship between coefficient values, that is, the first-stage coefficient value Z ₁ <the second-stage coefficient value Z ₂ <third. checks the coefficient values ZFD coefficient value Z ₃ ≦ fault detection element of the stage.

The relevance of the coefficient values of the timers associated with the characteristic example of FIG. 4 is checked by checking the first-stage timer T ₁ <the second-stage timer T ₂ <the third-stage timer T ₃ .

In step 106, the result of checking the coefficient is determined. If the result is normal, the process proceeds to step 107, where the signal line E in FIG.
The contents of the buffer memory 40 are written to the nonvolatile memory 21. The computer 60 recognizes the part where the coefficient has been changed using the number of coefficient values set in advance or a part of the buffer memory 40, and deletes all the contents of the buffer memory 40 or all necessary parts. Processing is performed to transfer the data to the nonvolatile memory 21.

Note that the signal line E may be connected to the nonvolatile memory 20, and the contents of the nonvolatile memory 20 may be directly transferred to the nonvolatile memory 21 without passing through the buffer memory 40.

The computer 60 checks whether or not the value written in the nonvolatile memory 21 matches the contents of the buffer memory 40 or the nonvolatile memory 20 as necessary. This check can be performed by reading the contents of the nonvolatile memories 20 and 21 directly via the signal line E or via the buffer memory 40. Further, the computer 60 writes the coefficient value into the nonvolatile memory 21 at the time of writing.
A check of deviation, a check of relevance, and the like may be performed.

When these processes are completed, the process advances to the process of step 108. Here, the computer 60 communicates via the signal line D,
The normal setting display 8 shown in FIG. 2 is turned on.

Next, at step 109, the operator confirms that the normal setting display 8 is lit on the coefficient setting panel, and receives an operation of turning off the coefficient confirmation switch 6 and the coefficient change command switch 5 by the operator.

When the coefficient change command switch 5 is turned off, the writing to the buffer memory 30 locked by the signal line A is released. As a result, the contents of the nonvolatile memory 21 storing the changed coefficient value are stored in the buffer memory 30 again.
Is written to.

The system uses the changed coefficient value from this point,
Operation to execute protection relay calculation.

On the other hand, in step 106 described above, if the determination result is abnormal, the process proceeds to step 110, where the computer 60
The abnormality setting display 9 is turned on via the signal line D.

In this case, the operator needs to return to step 101 and change the coefficient again from the beginning. However, at this time, if a function for displaying which coefficient change was abnormal in step 106 is added, it goes without saying that only the abnormal coefficient set value needs to be changed.

FIG. 5 shows the operation of the computer 60 in the above-described operation. The check CK of the coefficient value and the check CCK of the correlation between the coefficient values are performed by using the remaining time of the task processing TK in each sample period. Is shown.

Next, in the flowchart of FIG. 3, a description will be given of a response when the power of the computer 60 is cut off during the process of setting change.

When the power of the computer is turned off, the computer normally erases all initialized values in the RAM such as the buffer memory. In this embodiment, when the power is turned off, the contents of the buffer memories 30 and 40 in FIG. 1 are erased. Also, the signals on the signal line A and the like are all initialized once. For example, the command to write the coefficient value from the nonvolatile memory 21 to the data buffer memory 30 by the signal line A is stopped.

Thereafter, when the power is turned on again, the CPU 61 inside the computer 60 again performs initialization processing, for example, the RAM 63
Also, initialization of the buffer memories 30, 40 is performed. Here, in the initialization process, if the process of transferring the content of the non-volatile memory 21 to the buffer memory 30 is performed, the computer 60 can read the coefficient value before the power is turned off.

Even if the power is cut off while the coefficient changing operation is being performed, the present embodiment can cope with the following.

In other words, the contents of which are changed
20 is the non-volatile memory 21 because the value before the coefficient change operation is stored and held in the non-volatile memory 21
What is necessary is just to transfer the contents of 21 to the buffer memory 30. As a result, the computer 60 can perform an operation using the old coefficient value before the change. Therefore, before the operator determines whether or not to execute the calculation of the computer 60 with the changed coefficient value, it is possible that the computer 60 performs the calculation with the changed coefficient value due to the power interruption during the change of the coefficient value. Absent.

Further, even when the power is cut off while transferring the changed coefficient value to the nonvolatile memory 21, the following measures can be taken.

That is, by performing a compare check between the non-volatile memory 20 and the non-volatile memory 21 when the power is turned on, it is possible to check whether or not all the changed coefficient values have been transferred to the non-volatile memory 21. Even if not all of the changed coefficient values have been transferred to the non-volatile memory 21, the computer 60 can notify the outside by performing a display alarm by this check processing. For this reason, irregular coefficient values are used
The 60 operations are never performed.

The display alarm is given by, for example, the display 1,
This can be performed by the abnormality setting display 9. Also,
In addition to the display 1, a CRT display, a liquid crystal display,
A display such as a plasma display may be provided, and a message such as an alert, a countermeasure guide, or the like may be displayed on this display screen. Further, in addition to or separately from this, a warning or a guide by voice may be issued.

As the above-mentioned message, for example, “input value is cleared by turning off the power”, “the coefficient value is cleared by turning off the power, so input again” can be considered.

In the above description, the present embodiment (FIGS. 1 and 2)
Although only the main block configuration of the first embodiment is shown and described, the present embodiment also includes a configuration in which coefficients can be easily changed and settling errors do not occur, a required hardware configuration is reduced in size, and computer processing is performed. The structure has been designed with due consideration to improving the capacity.

First, consideration is given to the ease of changing the coefficient and to avoid setting errors, as follows.

(A) The coefficient setting switch on the coefficient setting panel is in decimal notation. Therefore, although not shown in FIG. 1, a decimal / binary conversion circuit is required before the value of the coefficient setting switch is input to the computer. When this circuit is not added, this processing must be performed by the CPU 61.

(B) By turning on the corresponding switch of the relay selection switch, the coefficient value used so far is displayed on the display so that the value to be changed can be confirmed.

The required hardware amount is reduced as follows.

(A) A coefficient setting switch is not provided for each element, and one switch is commonly used for each element.

(B) To that end, a function of storing the coefficient value is required, but a nonvolatile memory is required to enable automatic restart even when power is restored after a power failure. Moreover, in order to cope with the settling change, an electrically rewritable nonvolatile memory is required. Therefore, the semiconductor nonvolatile memory E ² PROM is adopted in consideration of the above points.

The computer is configured as follows to improve the processing capability.

(A) The computer does not directly access the non-volatile memory but accesses via the buffer memory. This solves the problem that, when the computer attempts to access the non-volatile memory due to the long access time of the non-volatile memory, the computer is restricted by the access time of the non-volatile memory and cannot exhibit the maximum processing capability. Is what it is.

(B) The coefficient range check at the time of coefficient change and the check of the relevance between coefficients as described above are described in the fifth section.
As shown in the figure, the idle time of the computer is effectively used.

In addition, the present invention can be configured as follows.

First, the number of nonvolatile memories is not limited to two, but may be three or more, and writing may be performed in multiple stages according to the number.

Secondly, a configuration may be adopted in which the contents of the non-volatile memories 20 and 21 are compared as necessary to check whether the set value has become abnormal.

In addition, in order to improve the reliability of this check, a nonvolatile memory is provided in addition to the nonvolatile memories 20 and 21, and the coefficient value is written to the nonvolatile memory 20 or 21 separately. At the same time, the contents of these memories may be checked to monitor whether there is any abnormality.

Third, a plurality of displays 1 shown in FIG. 2 may be provided, and the contents of the nonvolatile memories 20 and 21 may be separately displayed as necessary. The display 1 may be a large screen display such as a CRT display, and the contents of the nonvolatile memories 20 and 21 may be displayed on the same screen.

Fourth, as another embodiment of the coefficient setting panel 10 used in the present invention, it can be configured using a display device having a large display.

In this case, the display 1, the coefficient change display 7, the normal setting display 8, and the abnormal setting display 9 are arranged on the same screen, and these displays are not limited to simply turning on numbers or lamps, but also displaying messages. It can be configured to be displayed in a format.

Further, the coefficient setting switch 2 can be configured to input from a keyboard, a numeric keypad, or the like, store the input value in a buffer memory or the like, and display the input value on a display.

Further, the coefficient writing switch 3, the coefficient selection switch 4, the coefficient change command switch 5, and the coefficient confirmation command switch 6 are arranged by arranging a symbol figure indicating a switch on a display and designating the arrangement position with a mouse or the like. Alternatively, a corresponding key may be turned on / off by pressing a corresponding key from a keyboard. In this case, a light pen, a touch panel, or the like may be used as the switch instruction means.

In this embodiment, since the configuration is as described above, the following effects can be obtained.

(1) Since the coefficients are written into the first and second nonvolatile memories in two stages, even if the power is cut off while the contents of the first nonvolatile memory are being changed, the second nonvolatile memory is written. There is an effect that the operation of the computer can be executed by using the contents of (1).

(2) Even if the power is turned off while the coefficient value is being written to the second non-volatile memory, it is possible to detect an abnormality by checking the contents of the plurality of non-volatile memories.

(3) Arbitrary set value change at any time can be achieved without interrupting the operation of the computer.

(4) Since an arbitrary number can be set as the coefficient, the control characteristics can be easily changed, and the flexibility can be increased.

(5) Each time a coefficient is changed, the deviation of the value is checked (lens check), and the relevance between the coefficients after all the coefficient changes can be checked. Therefore, accurate coefficient changes can be easily performed.

(6) The set value can be maintained even when the power is turned off.

(7) The current coefficient value can also be easily seen.

(8) Since the idle time of the computer is used, for example, there is no obstacle to the operation for relay.

As described above, since the present embodiment can maximize the effect of introducing the computer, the practical advantage is very large.

The above embodiment is an example in which the present invention is applied to a protection system that performs a protection relay operation for electric power. However, the present invention is not limited to this, and a control system such as a system stabilization device, a plant control system such as steel, a railway It can be widely applied to control systems in traffic and transportation.

[Effects of the Invention] As described above, according to the present invention, even if the power supply is interrupted during the change of the coefficient setting, the protection and control calculations can be performed with the values before the coefficient change.

Therefore, according to the present invention, the system can be set with high reliability.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing the configuration of an embodiment of a power protection system to which the settling method of the present invention is applied, and FIG. 2 is a block diagram of a coefficient setting panel suitably used in the above embodiment. FIG. 3 is a diagram conceptually showing an example of the configuration, FIG. 3 is a flowchart showing the operation of the settling method in the above embodiment, FIG. 4 is a graph showing an example of the characteristics of a distance relay applicable to this embodiment, and FIG. Is a time chart showing the processing timing of the computer used in the above embodiment. 1 Display unit 2 Coefficient setting switch 3 Coefficient writing switch 4 Coefficient selection switch 5 Coefficient change command switch 6 Coefficient confirmation command switch 7
Coefficient change display, 8 Normal setting display, 9 Abnormal setting display, 10 Coefficient setting panel, 20, 21 Non-volatile memory, 30, 40 Buffer memory, 50 Input circuit , 60…
... Computer, 61 ... CPU, 62 ... ROM, 63 ... RAM, 7
0 ... Output circuit.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Minoru Seya 1-1-1, Kokubuncho, Hitachi City, Ibaraki Prefecture Inside the Kokubu Plant of Hitachi, Ltd. (56) References JP-A-56-1726 (JP, A) JP-A-58-86821 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H02H 3/02 G05B 7/02

Claims (2)

(57) [Claims] 1. A method for receiving a coefficient setting from the outside,
A coefficient setting panel for displaying a setting state; first and second nonvolatile memories for storing and holding coefficients set on the coefficient setting panel; and a coefficient value stored in the second nonvolatile memory. A buffer memory, a coefficient value stored in the buffer memory, and a computer that performs an operation for protection or control and controls the system based on information input from a protection or control target. The coefficient setting panel includes a coefficient change command switch that receives a coefficient change command input, a coefficient setting switch that receives a coefficient setting, a coefficient check command switch that receives an input of a set coefficient check command, and a setting content. And at least a display for displaying, and after the coefficient change command switch is turned on, until the coefficient change ends. 2, a process of stopping the writing from the nonvolatile memory to the buffer memory, a process of writing the set value by the coefficient setting switch to the first nonvolatile memory, and a confirmation command by the coefficient confirmation command switch. Sending a command to the computer, and after the writing to the first non-volatile memory is completed, the computer writes the content written to the first non-volatile memory to the second non-volatile memory If the power is turned off while the coefficient is being written to the first nonvolatile memory, when the system is restarted, the process of writing the contents of the second nonvolatile memory to the buffer memory is performed. And displaying a message requesting re-input of the data on the display unit. Is disconnected, the count values of the first nonvolatile memory and the second nonvolatile memory are compared. If the values stored in the two memories are different, an alarm signal is output to the outside. A control / protection system that performs processing. 2. When or after writing a new coefficient in the second nonvolatile memory, the contents stored in the second nonvolatile memory are compared with the contents stored in the first nonvolatile memory. 2. The control / protection system according to claim 1, further comprising a function of displaying a comparison result on said display.