JP2002238187A - Digital protector-controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out an operation based on digital information from a controller of higher order, without interfering with a protective and control computation. SOLUTION: An analog signal from an electric power system 30 is converted into a digital signal at an analog input unit 14. Based on the digital signal, a sequential computing unit 22 carries out protective and control computations related to an object to be protected and controlled, during the operation periods of 15 deg. of the first cycle of computation cycle of 30 deg., and sequentially outputs the result of the computation during each computation cycle of 30 deg.. When digital information related to simulation is inputted from a control computer 36, the analog input unit 14 and the sequential computing unit 22 carry out a computation related to simulation during the computation cycles of 15 deg. of the second half of computation cycle of 30 deg., and transfer the result of the computation to the control computer 36 via global memory 16 during each computation cycle of 30 deg..

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital protection / control apparatus, and more particularly to a power system and equipment connected to the power system which are to be protected / controlled and suitable for protecting the protected / controlled object from accidents and the like. Digital protection and control device.

[0002]

2. Description of the Related Art Conventionally, as a digital protection / control device, there is known a device using a digital protection relay (second generation digital relay) as described in, for example, Vol. Have been. A conventional device of this type includes an analog input unit, a digital operation processing unit, a settling unit, and an output unit.The analog input unit includes an analog filter for preventing aliasing errors, a sample and hold circuit, a multiplexer, An A / D converter and a buffer are provided. On the other hand, the digital arithmetic processing unit
It is divided into an input board for digital filter processing using high-speed sampling data and an operation board for protection control operation. The input board is mainly sampled at an electrical angle of 3.75 ° and obtained by sampling. A digital filter operation is executed based on the data thus obtained, and the operation result is transferred to the operation board once every 30 electrical degrees. In the calculation board, data is input every 30 °, and calculation processing, accident monitoring and mutual monitoring calculation are executed in accordance with the input data and the protection calculation algorithm, and finally, abnormality information is displayed on a panel, and LED ( Display is performed using a light emitting diode).

In this type of digital protection / control device, a configuration is adopted in which, at the time of remote operation, only the set value is taken from a remote control station or the like, and the set value is changed via a dedicated line and operated. ing.

[0004]

In the above prior art, at the time of remote operation, only a set value is transferred to a digital protection / control device from a control station serving as a higher-level control device. The setting value for tripping is changed, and operation is performed according to the changed setting value. However, the operation board only performs the accident monitoring and the mutual monitoring operation, but does not perform the process of determining whether the information transferred from the higher-level control device is appropriate, and the following problems occur. .

(1) When the set value is changed, it is impossible to dynamically calculate (verify) whether the set value is appropriate or not using a protection calculation algorithm built in the apparatus. That is, it is not possible to verify the form including the transient characteristics.

(2) In the constant monitoring process of the device, only hardware monitoring such as a memory check can be performed, and it is not possible to confirm a comprehensive calculation process as a protection relay.

(3) When the harmonic generation situation changes with the change in the system configuration, and it becomes necessary to change the characteristics of the filter used in the protection operation algorithm, the apparatus is temporarily stopped.
It is necessary to confirm the necessity of changing the filter characteristics. When the filter characteristics are changed, it is necessary to prepare an input signal generator and a measuring instrument in order to confirm the change in the filter characteristics with an actual device. There was a limit to remote control.

An object of the present invention is to provide a digital protection / control device capable of performing an operation based on digital information from a host control device without obstructing the protection / control operation.

[0009]

In order to solve the above-mentioned problems, the present invention provides an analog signal input means for inputting an analog amount of an electric signal from a power system, and an analog signal input from the analog input means for converting a digital signal into a digital signal. Analog-to-digital conversion means for converting digital data into digital information from a higher-level control device; and A second operation relating to the simulation based on the first arithmetic processing and the digital information input by the digital information input means;
Arithmetic processing means for executing the arithmetic processing in each arithmetic cycle, wherein the arithmetic processing means executes the first arithmetic processing and the second arithmetic processing separately within each arithmetic cycle,
Output the processing result of the arithmetic processing of
A digital protection / control device configured to output a processing result of the second arithmetic processing to the host control device is provided.

When the digital protection / control device is configured, the digital information input means may be configured to have a function of inputting digital information from a higher-level control device via a communication network.

In configuring each digital protection / control device, the following elements can be added.

(1) The arithmetic processing means executes the first arithmetic processing and the second arithmetic processing alternately in each arithmetic cycle.

(2) When the arithmetic processing means receives simulation data and digital information relating to the set value from the host control device, the arithmetic processing means performs, as a second arithmetic processing, the simulation data and the settled data inputted from the digital input means. A simulation including the validity of the set value is performed based on digital information on the value, and the result of the simulation is output to the host controller.

(3) The arithmetic processing means, when receiving digital information relating to the characteristic constant of the digital filter for removing harmonics from the higher-level control device, performs the second arithmetic processing based on the input of the digital input means as second arithmetic processing. A filter coefficient for the digital filter for removing harmonics is calculated based on digital information about a characteristic constant of the digital filter for removing harmonics, and a frequency characteristic of the digital filter for removing harmonics is calculated. Output to the device.

(4) The arithmetic processing means changes the characteristic of the harmonic elimination digital filter from the calculation result of the filter coefficient and the calculation result of the frequency characteristic during the second arithmetic processing, and the characteristic is changed. A simulation relating to filter characteristics is executed for the digital filter for removing harmonics, and the result of the simulation is output to the host controller.

(5) In the second arithmetic processing, the arithmetic processing means changes the characteristic of the digital filter for removing harmonics from the calculation result of the filter coefficient and the calculation result of the frequency characteristic, and performs the first arithmetic processing. In some cases, the first arithmetic processing is performed using a digital filter for harmonic removal whose characteristics have been changed.

According to the above-described means, when digital information is input from the host controller, the arithmetic processing means executes the first arithmetic processing and the second arithmetic processing separately in each arithmetic cycle. , The first arithmetic processing and the second arithmetic processing are alternately executed in each arithmetic cycle while avoiding duplication, and the processing result of the first arithmetic operation is output to the protection / control target, and the processing result of the second arithmetic operation is output. Is output to the higher-level control device, the arithmetic processing based on the digital information from the higher-level control device can be executed without obstructing the first arithmetic processing relating to the protection / control target, and the efficiency of the apparatus can be improved. Operation can be planned.

Further, a simulation including the validity of the set value is performed based on the simulation data and the digital information on the set value, and the simulation result is output to the host controller, so that the protection / control function is not stopped. The simulation can be performed consistently from the input digital information, and the reliability of the remote monitoring function of the digital protection / control device can be increased. Further, when the set value is changed, a simulation result regarding the validity of the set value can be confirmed before the operation starts after the set value is changed.

Further, since the filter coefficient is calculated based on the digital information on the characteristic of the digital filter for removing harmonics, the pressure collecting characteristic of the filter is calculated, and each calculation result is output to the host controller. When a change in filter characteristics occurs due to a change in system conditions or the like, confirmation of the changed filter characteristics can be performed by the host control device. Further, by changing the filter characteristics from the filter coefficient calculation results and the frequency characteristic calculation results, executing a simulation relating to the filter characteristics for the filters whose characteristics have been changed, and outputting the simulation results to the host controller, The simulation result of the filter whose filter characteristics have been changed can be confirmed in the host control device, which can contribute to the improvement of the reliability of the remote operation.

Further, by executing the first arithmetic processing using the filter whose characteristic has been changed, it is possible to confirm the remote operation and finally confirm the set value in the higher-level control device. Can be further increased.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram of a system including a digital protection / control device according to an embodiment of the present invention. In FIG. 1, the digital protection / control device 10
A plurality of input transformers 12, an analog input unit 14, a global memory 16, a network interface unit 18, a system bus 20, a protection / control sequence operation unit 22, a digital input / output unit 24, a human interface 26, and a display 28 Each input transformer 12 is connected to a power system 30, the network interface unit 18 is connected to a communication network 34 via a network cable 32, and the communication network 34 is a control computer serving as a higher-level control device. The control computer 36 has a database 38 connected thereto.
Is connected.

Each input transformer 12 receives an AC voltage signal and a current signal as analog electric signals from the power system 30 through each signal line, and converts the AC voltage to an electronic circuit level, for example, ± 10 volts or less. It is configured as analog signal input means for converting the voltage into a voltage and outputting the converted voltage to the analog input unit 14. The analog input unit 14 is configured as analog-to-digital conversion means for converting an analog signal output from each input transformer 12 into a digital signal, and performs a digital filter operation based on digital data obtained from the digital signal. And outputs the operation result to the global memory 16 and the system bus 20.

Specifically, the analog input unit 14
As shown in FIG. 2, a plurality of analog low-pass filters 40, a multiplexer 42, an oscillator 44, a timing control circuit 46, an A / D (analog / digital) converter 4
8, buffer memory 50, microcomputer (CP
U) 52, system bus 54, interrupter 56, program memory (ROM) 58, data memory (RAM)
60, a global memory interface 62, and a system bus interface 64, and each analog low-pass filter 40 is connected to each input transformer 1
2, the interrupter 56 is connected to the sequence operation unit 22, the global memory interface 62 is connected to the global memory 16, and the system bus interface 64 is connected to the system bus 20.

Each analog low-pass filter 40 removes a harmonic component from a signal included in the analog signal input from each input transformer 12, outputs only a low-frequency component signal to the multiplexer 42 in sequence, and returns an aliasing error due to sampling. To reduce the effect. The multiplexer 42 sequentially selects the analog signals that have passed through each analog low-pass filter 40 in response to the multiplexer switching signal 66 from the timing control circuit 46, and outputs the selected analog signals to the A / D converter 48. I have. The A / D converter 48 includes a timing control circuit 46
The analog signal is converted into a digital signal in response to the A / D conversion start signal 68 output from the
0 is output. Buffer memory 50
Sequentially stores system data (data related to the voltage and current of the power system 30) obtained from a digital signal in a designated storage area in response to an address signal 70 and a memory write signal 72 output from the timing control circuit 46. It is supposed to.

The microcomputer 52 executes arithmetic processing according to a program stored in the program memory 58 at regular intervals in response to an interrupt signal 74 output from the timing control circuit 46. . During normal operation, system data stored in the buffer memory 50 is fetched, and digital filter processing is performed on the fetched system data. On the other hand, when digital information is input from the control computer 36, various calculations are performed based on the digital information. For example, at the time of a simulation, an operation related to the simulation is performed using simulation data input from the global memory 16 via the global memory interface 62. When the interrupt start signal 76 is output from the timing control circuit 46 to the interrupter 56, the interrupt signal 78 is output from the interrupter 56 to the sequence operation unit 22, and the interrupt release signal 80 is input from the sequence operation unit 22. At times, the output of the interrupt signal 78 is stopped.

At the time of simulation, when the microcomputer 52 inputs digital information from the control computer 36, the global memory 16 stores the analog input interface 16a, the CPU bus interface 16b, the buffer 16c, and the buffer 1 as shown in FIG.
6d, a dual port memory 16e, and a communication unit interface 16f. The analog input interface 16a is
2, the CPU bus interface 16b is connected to the sequence operation unit 22, and the communication unit interface 16f is connected to the network interface unit 18
It is connected to the. The dual port memory 16e is asynchronously accessed from the three interfaces 16a, 16b and 16f, accessed from the analog input interface 16a via the buffer 16c, and accessed from the CPU bus interface 16b. 16d, the ports are exclusively selected by these accesses.

The access from the communication interface 16f is randomly performed asynchronously with the access on the buffers 16c and 16d. And
The digital information from the control computer 30 including digital data, for example, simulation data, data relating to the set value for tripping the circuit breaker, etc.
As shown in (a), the data is transferred to the analog input unit 14 via the network interface unit 18, the communication unit interface 16f, the dual port memory 16b, the buffer 16c, and the analog input interface 16a. The system data includes an analog input interface 16a, a buffer 16c,
Dual port memory 16e, communication unit interface 1
6f, the network interface unit 18 and the control computer 36 via the communication network 34.

The data of the simulation result by the processing of the sequence operation unit 22 is controlled via the CPU bus interface 16b, buffer 16d, dual port memory 16e, communication unit interface 16f, network interface unit 18, and communication network 34. The data is transferred to the computer 36.

On the other hand, the protection / control sequence calculation unit 22 shown in FIG. 1 receives set values and set values for protection / control calculation in the form of conversation with the operator via the human interface 26, When data relating to the state of the power system is input from the analog input unit 14, the power system 30 and devices connected to the power system 30 are set as protection / control targets, and arithmetic processing for protecting / controlling the protection / control target ( 1), and outputs the calculation result to the protection / control target via the digital input / output unit 24.

Further, the protection / control sequence operation unit 22 performs a second operation related to a simulation or the like based on the operation result of the analog input unit 14 for each operation cycle, for example, for each electrical angle of 30 °. Through the global memory 16, the network interface unit 18, and the communication network 34.
6 is output.

That is, the analog input unit 14 and the protection / control sequence operation unit 22 are configured as operation processing means, and this operation processing means performs the first operation processing and the second operation processing separately in each operation cycle. In addition, for example, each arithmetic processing is executed alternately without duplication.

Next, the operation of the digital protection / control device will be described with reference to FIG. In processing an analog signal from the power system 30, in the present embodiment, the electrical angle 30
The operation cycle generated at every ° (t1 to t7) is divided into 8
An electrical angle of 3.75 ° (１ ／ times 7.5 °) is set as a basic calculation cycle, and an analog signal is converted into a digital signal every 7.5 ° in the calculation cycle at timings t1 to t6. Further, each calculation cycle at an electrical angle of 30 ° is divided into four, and the four divided cycles are each divided into two to divide into first half 1-4 and second half 1′-4 ′,
At the calculation timing of 3.75 ° in the first half of the calculation cycle, the first
As the arithmetic processing, the analog signal is converted to a digital signal, and the second arithmetic processing based on the digital information transferred from the control computer 36 at the arithmetic timing of 3.75 ° in the latter half of the arithmetic cycle, for example, according to simulation data. The arithmetic processing is executed and the processing result is protected from the analog input unit 14 by the protection / control sequence arithmetic
You are going to transfer to.

Here, when the first arithmetic processing is executed in the sequence arithmetic unit 22, the first arithmetic processing (A) for protecting and controlling the protection / control target based on the system data relating to the power system 30 is performed. ) Are sequentially executed within the first half of the calculation cycle of the electrical angle of 30 °, and the calculation results are sequentially output for each electrical angle of 30 °.

On the other hand, when digital information (simulation data and set value data) for performing a simulation is input from the control computer 36 and the simulation start flag is turned on, the second calculation processing (B) relating to the simulation is performed by the sequence calculation control unit. 22. This calculation is performed with an electrical angle of 30
The calculation is performed within the latter 15 ° calculation cycle of the calculation cycle of °, and the calculation result is output for every electrical angle of 30 °. The data transfer path at this time is shown in FIG.

In the process of performing a simulation based on the simulation data and the set value data, FIG.
As shown in (a), the first arithmetic processing (A) is performed in the analog input unit 14 and the sequence arithmetic unit 22. At this time, when data for performing a simulation is transferred from the control computer 36, data is exchanged between the control computer 36 and the network interface unit 18, and simulation data communication is being performed. Thereafter, when the download of the data is completed, the simulation calculation processing by the analog input unit 14 and the sequence calculation unit 22 is executed. As the simulation data at this time, as shown in FIG. 6B, data relating to voltage and current are input, and a simulation based on these data is performed.

In this case, by inserting an accident occurrence flag into the simulation data and executing a simulation at the time of occurrence of the accident according to the accident occurrence flag, the time from the occurrence of the flag to the relay operation for tripping the circuit breaker can be reduced. It can be measured accurately.

That is, the most important factor in the simulation is whether or not the relay operates according to the protection operation / sequence processing and the set value currently being operated.
Alternatively, it is necessary to know whether or not the operation time is accurate.
Therefore, by inserting a flag indicating the start of an accident into the simulation data,
Whether the relay operates correctly or not can be easily grasped by the sequence processing and the set value.
The operation when the set value is changed can be easily confirmed.

Next, when confirming the characteristics of the digital filter for removing harmonics used in the analog input unit 14, the control computer 36 outputs digital information on the characteristic constant of the digital filter for removing harmonics as digital information.
When the data of the filter coefficient or the filter characteristic constant is transferred, the data is transmitted / received through a route as shown in FIG. At this time, the analog input unit 14 calculates a filter coefficient from the filter characteristic constant, generates a single-frequency sine wave in order to obtain a frequency characteristic, and uses the generated sine wave signal as an input signal as a digital filter. And calculates the ratio of the amplitude of the output signal output from the digital filter to the amplitude of the input signal to calculate the frequency characteristic of the digital filter.

The generated sine wave signal is input to a digital filter, the effective value of the output signal of the digital filter is obtained, and the gain / frequency characteristic of the digital filter is obtained as shown in FIG. The global memory 16 stores a pair of data on the frequency of the input signal and the gain (gain = output / input) for the frequency of the input signal.
To be stored.

As for the phase, as shown in FIG. 7B, the generated input signal is input to a digital filter, the delay time of the output signal with respect to the input signal is detected, and this delay time is converted into a delay phase. Then, the data on the frequency of the input signal and the phase with respect to the input signal are stored in the global memory 16 as a pair.

These processes are executed while the simulation flag is set, as in the case of the simulation value. The data stored in the global memory 16 is sequentially transferred to the control computer 36, and
When a change in filter characteristics occurs due to a change in system conditions or the like on the side, a result accompanying the change in filter characteristics can be confirmed.

The operation for checking the filter characteristics is performed at the timing shown in FIG. That is, the control computer 36 and the network interface unit 18
Data transmission / reception regarding the filter coefficient of the digital filter is performed between them, and the calculation for obtaining the frequency characteristic of the filter is performed on condition that the download of the data is completed and the simulation flag is set. When the frequency characteristic is obtained by the above-described method, that is, when the frequency characteristic of the input signal is swept and the frequency characteristic is calculated, data is exchanged between the network interface unit 18 and the control computer 36. The data is uploaded to the control computer 36.

When calculating the frequency characteristic of the digital filter, as shown in FIG. 9, a filter characteristic constant, for example, in the case of a low-pass notch filter, the zero-point frequency ω
n, cutoff frequency ω0, selectivity Q, sampling frequency T
From the filter coefficients A1, A2, B1, B2, and H. That is, although the filter coefficient can be obtained from the characteristic constant of the filter, the frequency characteristic of the digital filter can be calculated by directly receiving the data regarding the filter coefficient from the control computer 36 of the higher system.

Further, the characteristic data and the data relating to the simulation result as shown in FIG. 7 are displayed on the screen of the control computer 36, and by checking the characteristic and the simulation result displayed on the screen, the validity of the set value and the like is obtained. And the characteristics of the filter can be confirmed.

In some cases, it is necessary to confirm the operation as a protection relay in response to a change in the characteristics of the harmonic elimination filter. Operation support can be provided.

When monitoring system data,
As shown in FIG. 5C, digital data generated by the A / D converter 48 is generated as system data by the analog input unit 14, and the system data is transferred to the control computer 36 via the global memory 16. Therefore, the state of the system can be analyzed by the control computer 36 located at a remote place.

As described above, in the present embodiment, the first calculation processing (A) is performed in half (50%) of the calculation cycles of the electrical angle of 30 °, and the other half (5%) is performed.
0%), the second arithmetic processing (B) is performed so as to avoid duplication with the first arithmetic processing. Therefore, arithmetic processing based on digital information from a higher-level control device while performing protection / control arithmetic. And the operation by the digital protection / control device can be performed efficiently.

Further, according to the present embodiment, the simulation including the validity of the set value is performed based on the simulation data and the digital information on the set value, and the simulation result is output to the control computer 36. Simulation can be performed consistently from the input digital information without stopping the control function.
It is possible to increase the reliability of the remote monitoring function for the digital protection / control device. Further, when the set value is changed, a simulation result regarding the validity of the set value can be confirmed before the operation starts after the set value is changed.

Further, according to the present embodiment, the filter coefficient is calculated based on the digital information on the characteristics of the digital filter for removing harmonics, the pressure collecting characteristics of the filter are calculated, and each calculation result is output to the control computer 36. Therefore, when a change in filter characteristics occurs due to a change in system conditions or the like, the changed filter characteristics can be confirmed in the host control device.

Further, the filter characteristics are changed based on the calculation results of the filter coefficients and the frequency characteristics, a simulation relating to the filter characteristics is executed for the filter whose characteristics have been changed, and the simulation result is output to the control computer 36. By doing so, the control computer 36 can check the simulation result regarding the filter whose filter characteristic has been changed, which can contribute to the improvement of the reliability of the remote operation.

Further, by executing the first arithmetic processing using the filter whose characteristics have been changed, the control computer 36 can confirm the remote operation and the final confirmation of the set value. Can be further increased.

[0052]

As described above, according to the present invention,
When digital information is input from the host controller, the arithmetic processing means executes the first arithmetic processing and the second arithmetic processing separately in each arithmetic cycle, and protects / controls the processing result of the first arithmetic processing. Output to the target and output the processing result of the second operation to the host control device, so that the operation process based on digital information from the host control device inhibits the first operation process for the protection / control target. The operation can be performed without performing, and efficient operation of the apparatus can be achieved.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a system including a digital protection / control device according to a first embodiment of the present invention.

FIG. 2 is a block diagram of an analog input unit.

FIG. 3A is a block diagram of a global memory;
FIG. 3B is a diagram for explaining a data flow in which a global memory is used as an intermediary.

FIG. 4 is a time chart for explaining the operation of the digital protection / control device shown in FIG. 1;

FIGS. 5A to 5C are diagrams for explaining a data flow of the digital protection / control device shown in FIG. 1;

FIGS. 6A and 6B are time charts for explaining a simulation operation of the digital protection / control device shown in FIG. 1;

FIG. 7A is a gain characteristic diagram of a digital filter;
(B) is a phase characteristic diagram of the digital filter.

FIG. 8 is a time chart for explaining arithmetic processing relating to frequency characteristics of the digital protection / control device shown in FIG. 1;

FIG. 9A is an equivalent circuit diagram of a digital filter,
(B) is an explanatory diagram of the configuration of the filter coefficient.

[Explanation of symbols]

 Reference Signs List 10 digital protection / control device 12 input transformer 14 analog input unit 16 global memory 18 network interface unit 20 system bus 22 protection / control sequence calculation unit 24 digital input / output unit 26 human interface 28 display 30 power system 32 network Cable 34 communication network 36 control computer 38 database

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinji Saito 1-1-1, Kokubuncho, Hitachi City, Ibaraki Prefecture Inside the Electric Systems Division, Hitachi, Ltd. (72) Inventor Takashi Kobayashi 1-1-1 Kokubuncho, Hitachi City, Ibaraki Prefecture No. 1 F-term in the Electric Systems Division, Hitachi, Ltd. (Reference) 5G042 GG01 GG06 5G064 AA04 AB03 AC05 AC08 CA00 CB03 DA01 5H223 CC08 DD03 DD07 EE04 FF05

Claims (7)

[Claims] 1. An analog signal input means for inputting an analog electric signal from a power system, an analog / digital conversion means for converting an analog signal input from the analog input means into a digital signal, and digital information from a higher-level control device. Digital information input means for inputting a digital signal, first arithmetic processing for protecting and controlling an object to be protected and controlled based on a digital signal converted by the analog / digital conversion means, and digital information input from the digital information input means. Based on the simulation
Arithmetic processing means for executing the arithmetic processing in each arithmetic cycle, wherein the arithmetic processing means executes the first arithmetic processing and the second arithmetic processing separately within each arithmetic cycle,
Output the processing result of the arithmetic processing of
A digital protection and control device for outputting a processing result of the second arithmetic processing to the host control device. 2. An analog signal input means for inputting an analog electric signal from a power system, an analog / digital conversion means for converting an analog signal input from the analog input means into a digital signal, and a communication network from a host controller. Digital information input means for inputting digital information via the digital signal input means, first arithmetic processing for protecting and controlling an object to be protected / controlled based on a digital signal converted by the analog / digital conversion means, and the digital information input means Arithmetic processing means for executing a second arithmetic processing relating to the simulation at every arithmetic cycle based on the digital information by the input of the above, wherein the arithmetic processing means performs each of the first arithmetic processing and the second arithmetic processing. Executing separately within an operation cycle, outputting a processing result of the first operation processing to a protected / controlled object, A digital protection / control device for outputting a processing result of the second arithmetic processing to the host control device via the communication network. 3. The digital protection / control device according to claim 1, wherein said arithmetic processing means comprises:
A digital protection / control device characterized by alternately executing the arithmetic processing of the above and the second arithmetic processing in each arithmetic cycle. 4. The digital protection / control device according to claim 1, wherein the arithmetic processing means receives the simulation data and digital information relating to the set value from the host control device, and executes the second processing. As an arithmetic process, a simulation including the validity of the set value is performed based on the simulation data and digital information on the set value by the input of the digital input means,
A digital protection / control device, wherein the simulation result is output to the host control device. 5. The digital protection / control device according to claim 1, wherein said arithmetic processing means receives digital information on a characteristic constant of a digital filter for removing harmonics from said higher-level control device. In the second arithmetic processing, a filter coefficient for the harmonic elimination digital filter is calculated based on digital information on a characteristic constant of the harmonic elimination digital filter by an input of the digital input means. Calculate the frequency characteristics of the digital filter,
A digital protection / control device, wherein each calculation result is output to the host control device. 6. The digital protection / control device according to claim 5, wherein the arithmetic processing unit performs the second harmonic processing based on the filter coefficient calculation result and the frequency characteristic calculation result during the second calculation processing. A digital protection / digital filter characterized in that the characteristics of the filter are changed, a simulation relating to the filter characteristics is executed for the digital filter for harmonic removal whose characteristics have been changed, and the simulation result is output to the host controller. Control device. 7. The digital protection / control device according to claim 5, wherein the arithmetic processing unit performs the second harmonic processing based on the calculation result of the filter coefficient and the calculation result of the frequency characteristic during the second arithmetic processing. A digital protection / control device, wherein a characteristic of a filter is changed, and a first arithmetic processing is executed at the time of the first arithmetic processing by using a digital filter for harmonic removal whose characteristic has been changed.