JP2002152964A - Inspection system of digital protective relay device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology which makes it possible to inspect digital protective relay devices in a substation built in a remote rural area, such as a place in the mountains, etc., without a trip to the substation which requires a long time and a trouble of an operator and hence is not efficient. SOLUTION: Electric value transmission units which output calculation results, obtained by a calculation method same as a protective calculation, are provided in a plurality of digital protective relay devices, in addition to relay decision units outputting the protective calculation results. The calculated values of a plurality of the electric value transmission units are transmitted to a common data collection means via signal transmission routes and the collected data are inputted to a propriety decision unit to decide whether the digital relay devices are defective or not.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection method of a digital protection relay using a quantity of electricity taken from an electric power system to determine the quality of the device. The present invention relates to an inspection method for a digital protection relay device which takes in the electric quantity data obtained by the above and makes a judgment.

[0002]

2. Description of the Related Art Conventionally, when inspecting a digital protection relay device of an electric power system, an electric quantity having a level clearly higher than the power flow level of the system is artificially input, particularly an analog input processing unit and other input processing units. It took a lot of trouble and time to check the quality of the work.

[0003] In particular, when inspecting a digital protective relay installed in a remote mountainous substation, an operator periodically goes to the site to manually input an inspection input and perform an inspection. Had gone. Also, during the inspection period, it was necessary to lock the device and suspend the operation.

[0004]

As described above, going to a substation installed in a remote place such as a mountainous area for inspection of a digital protection relay requires a lot of time and labor for an operator. Instead, it is not efficient. For this reason, there has been a long-awaited need for an inspection method capable of performing an inspection operation of a digital protective relay without visiting a substation.

According to the present invention, even during normal operation at a remote substation or the like, the data of a relay device is collected from a remote location and the quality of the device is determined, thereby making it possible to perform a periodic operation without manpower and time. It is an object of the present invention to obtain an inspection method for a digital protection relay device that enables simplification of inspection work and improvement of efficiency.

[0006]

In order to achieve the above object, the invention of the inspection system for a digital protection relay device according to the present invention is characterized in that an analog electric quantity input from an electric power system is sampled at a constant period. In the inspection method of the digital protection relay device, which performs a protection calculation based on a predetermined protection calculation program after converting the digital protection relay device into a digital quantity and further performing a filtering process, a plurality of the digital protection relay devices are prepared. Each of the digital protection relays includes a relay determining unit that outputs a protection operation result and an electric amount transmitting unit that outputs a result of calculating the input electric amount by the same operation method, and is transmitted from these electric amount transmitting units. The collected electricity is collected by a common data collection unit via a signal transmission path, and the collected data is input to a pass / fail judgment unit for pass / fail judgment. Since the pass / fail judgment is made using the formula, even if the digital protection relay is installed at a remote substation in a mountainous area, the workers do not go to the site and the amount of system electricity in normal times Can be used for inspection work.

According to a second aspect of the present invention, there is provided an inspection system for a digital protection relay device, comprising: an input electric amount detecting means for detecting that an analog electric amount input from the electric power system is equal to or less than a predetermined value; An input device and an input switching unit that operates so as to switch from a power system to a simulated input device and take in a simulated input based on an operation output of the input electric quantity detection unit are provided. When the value is equal to or less than the predetermined value, the system is switched so as to apply the simulated input instead of the actual input of the system, so that the level of the actual system electric quantity is small, and a detection error when detecting a failure of the analog input processing unit is reduced. Even in the case where it becomes large, it is possible to detect a failure of the device by switching to the simulation input.

Further, according to a third aspect of the present invention, there is provided an inspection system for a digital protection relay device, wherein a judgment result storage means for storing past data of a judgment value obtained by the pass / fail judgment section is provided. Is compared with the determination value at the time of the nearest inspection, so that a failure determination or a sign of failure can be detected based on the trend of the determination data.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a block diagram of a first embodiment of an inspection system for a digital protection relay device according to the present invention.

In FIG. 1, DigRy1 and DigRy2 are digital protective relays, both of which are analog voltages and currents measured by PT and CT installed at terminals of a transmission line TL which is the same protection target. Quantity), input converter 1
After that, the signal is input to the analog / digital converter 2, where it is converted into a digital quantity suitable for digital operation, and then input to the digital processor 3.

The digital processor 3 includes a buffer memory for storing A / D-converted digital data, a program memory for storing a program, a CPU for performing calculations in accordance with the contents of the program memory, a setting memory for storing a set value, and an output circuit. And its functions are as shown in the block diagram of FIG.

That is, the digital electricity introducing unit 3-1 fetches A / D-converted digital data, performs a filtering process, and outputs the digital data to the input processing unit 3-2. The input processing unit 3-2 calculates instantaneous value data using the input digital amount. The electric quantity sending section 3-3 sends the instantaneous value data calculated by the input processing section 3-2 to an external signal transmission path 4 such as a LAN. The relay determination unit 3-4 performs a relay operation according to a predetermined program using the output digital amount of the input processing unit 3-2, and outputs a shutoff command to a circuit breaker (not shown) if the operation condition of the relay is satisfied. Is what you do.

Reference numeral 5 denotes a data processing device (hereinafter, referred to as a personal computer) such as a personal computer installed at a place different from the digital protection relay devices DigRy1 and DigRy2, and is connected to the signal transmission line 4. Although not shown, the personal computer is provided with a printer in addition to the monitor.

The internal functions of the personal computer 5 include the digital protection relay devices DigRy1 and DigRy1.
A data collection unit 5-1 for collecting data such as instantaneous values output from both Ry2 via an interface, and substituting the collected data into a predetermined arithmetic expression to protect the relay device Di.
Pass / fail determination unit 5-2 that determines pass / fail of the gRy1 and DigRy2 devices.
It has.

The pass / fail judgment unit 5-2 uses, for example, the following judgment formula (1), and when this judgment formula (1) is satisfied,
It is determined that the digital protection relay devices DigRy1 and DigRy2 are defective.

| IAmax−IBmax | ≧ ε + k (| IAmax | + | IBmax |) (1) where, ε: fixed component error, k: proportional component error IAmax = MAX (IAm to IAm-i) (I: 0 to n seconds) n
Maximum value in seconds. IBmax = MAX (IBm to IBm-i) (i: 0 to n seconds) n
Maximum value in seconds. IAmax: The maximum value of the electric quantity of the digital protection relay DigRy1 for n seconds. IBmax: The maximum value of the electric quantity of the digital protection relay DigRy2 for n seconds. | IAmax-IBmax |: (difference between the maximum value of the A device and the B device for n seconds)

The above equation (1) means that the magnitude of the electric quantity of the transmission lines input to the plurality of digital protection relay devices DigRy1 and DigRy2 installed for one transmission line is the same ( The same quantity of electricity taken in via the instrument transformer PT or the current transformer CT)
The maximum value for n seconds of the electric quantity data collected by the data collection unit 5-1 from the digital protection relay devices DigRy1 and DigRy2 is taken into the pass / fail determination unit 5-2, and the two devices DigRy1, Di
If the absolute value of the difference between the electric quantities of gRy2 is larger than the sum of the fixed error and the electric quantity data of the two apparatuses multiplied by the proportional error, it is determined that one of the two apparatuses is defective. .

According to this embodiment, it is possible to detect a defect such as a phase characteristic of an electric quantity input circuit (analog input processing unit) of each digital protection relay without being affected by the power system. An inspection method of the digital protection relay can be provided.

(Second Embodiment) FIG. 2 shows a second embodiment of the present invention.
FIG. 2 is a configuration diagram of a digital protection relay device according to an embodiment of the present invention. The transformer PT is not shown in the drawing due to space limitations. The same applies to the following embodiments. This embodiment is a digital protection relay DigRy
1. Install three or more devices, DigRy2, DigRy3, etc., fetch data from each of these digital relay devices DigRy1, DigRy2, DigRy3, etc. into the personal computer 5, and compare the data for determining the failure of the digital protection relay device. In this method, data is obtained from three or more devices. According to the present embodiment, it is possible to specify which device the defective device is.

(Third Embodiment) FIG. 3 is a block diagram of an inspection system of a digital protection relay device according to a third embodiment of the present invention. Avoid the explanation given. The transformer (PT) is omitted due to space limitations.

In this embodiment, a shortage-of-electricity detection unit 3-5 is provided which operates when the actual input of the power system falls below a predetermined value, and the input switch 6 is operated by the output of the shortage-of-electricity detection unit 3-5. Is applied instead of the actual input of the electric power system.

According to the present embodiment, even when the input level of the actual system electric quantity is small and the detection error when detecting a defect in the analog input processing section becomes large, the digital input can be switched to the simulation input device. Defective protection relay device can be detected.

(Fourth Embodiment) FIG. 4 is a configuration diagram of an inspection system of a digital protection relay device according to a fourth embodiment of the present invention.

In this embodiment, the past data of the judgment value obtained by the judgment formula in the pass / fail judgment unit 5-2 is stored in a newly provided data storage means 5-3 in the configuration shown in FIG. In addition, the newly provided trend calculation unit 5-4 compares the current determination value with the determination value at the past (for example, the previous inspection), and determines a failure or a sign of failure according to the trend (trend) of the determination data. This is to detect.
The device failure is detected by substituting the electric quantity data into the determination formula (2).

Xi = | IAmax−IBmax | / (k + | IAmax | + | IBmax |) | Xn−Xn−1 | ≧ *% (2) where Xn: present determination value Xn−1: Previous Determination Value According to the present embodiment, it is possible to roughly predict when the device will be defective.

By using the judgment value X0 for the first time as the judgment value for the past, it is possible to know the degree of deterioration of the analog input processing unit particularly from the initial stage of device delivery, based on the trend of the judgment data. | Xn−X ₀ | ≧ *% (3) where X _{0 is the} initial determination value, Xn is the current determination value

(Embodiment 5) This embodiment is different from the fourth embodiment shown in FIG. 4 in that past data of a judgment value obtained by a pass / fail judgment unit 5-2 using a judgment expression of a defect judgment is stored in a data storage unit 5. -3, the trend calculation and prediction unit 5
According to -5, the future judgment value is predicted based on the trend (trend) of the judgment data at the time of the previous or previous inspection, and if it is judged that the judgment value deviates from the predetermined value in the future, an alarm will be issued by a defect judgment. It is configured to emit. According to the present embodiment, it is possible to reduce the time during which the device cannot be operated, such as by replacing the component before the device becomes defective, and to improve the operation rate of the system.

(Sixth Embodiment) In this embodiment, of the electric quantities transmitted from the two digital relay devices, the device having the larger zero-phase component is determined to be defective. According to the present embodiment, it is possible to determine which of the two devices is defective.

(Seventh Embodiment) In this embodiment, of the electric quantities transmitted from the two digital relay devices, the device having the larger change in the trend of the defect judgment data is determined by the pass / fail judgment unit 5-2b. This is a method of judging a failure. According to the present embodiment, even when it is difficult to determine the quality of the zero-phase component due to the influence of the system phenomenon, it is possible to determine which of the two devices is defective.

(Eighth Embodiment) In the present embodiment, an intelligent mobile agent (software that autonomously repeats processing between computers and various devices connected via a network) agent in a personal computer 5 To collect data, determine the quality of the digital relay device,
Further, the system is such that the agent displays the inspection result of the device and the judgment result of the defect on the operation screen in the format of a report.

According to the present embodiment, the inspection work can be performed by merely performing a patrol instruction operation on the intelligent mobile agent without a human having to access each device each time, and a defect of the device can be detected. .

Further, since data is collected without a human having to access each device each time, a defect detection of the device and a report thereof are automatically created in a format designated in advance.
It can be attached and sent by e-mail, or printed out and quickly distributed to relevant places. In addition, in addition to the above-described embodiments, the present invention can be implemented with some modifications as follows.

(Modification) In the first embodiment, the instantaneous value of the electric quantity is used for the defect determination. However, the present invention is not limited to the instantaneous value alone, and the defect determination is performed using the effective value. You may. When the effective value is used, strict time synchronization between devices on the order of several microseconds is not required, and inspection for comparing the electric quantity can be performed between devices of different manufacturers having different analog input processing unit specifications.

(Modification) Two digital protection relays are used.
The data may be taken in between the two streams, and the data may be compared to determine the apparatus. As described above, when data comparison is performed between two systems, a device failure can be more strictly detected.

(Modification) Data at the time of a power system accident may be used as an input source for inspection of the digital protection relay. If the electric quantity at the time of the accident is adopted, the electric quantity level is large and various frequencies are included, so the characteristics of the analog input processing unit can be analyzed without applying a high-level inspection input artificially. Defective equipment can be detected.

(Modification) The data collection unit 5-1 may be configured so that the acquisition time of electric quantity data between a plurality of devices can be changed to an arbitrary value. In this case, even if the amount of electricity in the system fluctuates at certain time intervals, the data acquisition time can be adjusted to the fluctuation cycle, so that a device failure can be detected.

(Modification) The data collection unit 5-1 may be configured so that the acquisition interval of the electric quantity data between a plurality of devices can be changed to an arbitrary value. In this case, even when the amount of electricity in the system fluctuates at certain time intervals, the data acquisition period is adjusted to the fluctuation period,
There is no need to worry about acquiring more data than necessary, and it is possible to configure a system in which the memory capacity and the storage capacity of hardware related to data collection are less likely to be reduced.

(Modification) As shown in FIG. 2, three or more digital protection relays are installed and a failure judgment is performed by a common pass / fail judgment unit 5-4. The determination data is compared, and if the data of a certain device is clearly different from the determination data of most other device groups, the device is determined to be defective.
According to the present embodiment, it is possible to determine which device is defective.

(Modification) In the configuration diagram shown in FIG. 4, the data obtained when the data fetched by the personal computer 5 at the previous time or the data at the time of fetching past data is stored and stored. In this method, a trend of data is calculated, and if the change in the trend is large and the rate of change exceeds a predetermined value, it is determined to be defective. According to the present embodiment, even when there is no object to be compared or when the data of the device to be compared cannot be collected for some reason, the failure can be detected by the device alone.

(Modification) In this case, the personal computer 5 is installed in a place remote from the digital relay devices DigRy1 and DigRy1 and DigRy1, and a general-purpose Internet browser is operated on the device, and the results of the remote operation and the defect judgment of the device are determined. This is a display method. According to the present embodiment, it is not necessary to develop dedicated communication software for displaying the result of remote control of the apparatus and the result of the failure determination, and therefore, it is possible to reduce the cost of system construction.

[0041]

As described above, the present invention focuses on the fact that the transmission lines input to a plurality of digital protection relays installed on one protection target have the same amount of electricity. By remotely collecting the electric quantities input by these multiple devices and comparing them using a failure judgment formula, the characteristics of the electric quantity input circuit of each digital protection relay can be changed without being affected by the system side. Digital protection relays that can be realized without the need for humans to go to the site as usual and that use ordinary system electricity to save labor and achieve relatively simple and low-cost system construction. An inspection method of the electric device can be provided.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a first embodiment of the present invention relating to an inspection method of a digital protection relay device.

FIG. 2 is a configuration diagram illustrating a second embodiment of the present invention relating to an inspection method of the digital protection relay device.

FIG. 3 is a configuration diagram for explaining a third embodiment of the present invention relating to a check method of a digital protection relay device.

FIG. 4 is a configuration diagram illustrating a fourth embodiment of the present invention relating to a check method of a digital protection relay device.

FIG. 5 is a configuration diagram illustrating a fifth embodiment of the present invention related to a check method of a digital protection relay device.

FIG. 6 is a configuration diagram for explaining a sixth embodiment of the present invention relating to an inspection method of a digital protection relay device.

FIG. 7 is a configuration diagram for explaining a seventh embodiment of the present invention relating to an inspection method of a digital protection relay device.

FIG. 8 is a configuration diagram for explaining an eighth embodiment of the present invention relating to an inspection method of a digital protection relay device.

[Explanation of symbols]

DigRy1, DigRy2: Digital protective relay, 1 ... Input converter, 2 ... Analog / digital converter, 3 ... Digital processor, 3-1 ... Digital electricity introduction unit, 3-2 ...
Input processing unit, 3-3: electric quantity sending unit, 3-4: relay determining unit,
3-5: Deficient amount of electricity detection unit, 4: Signal transmission line, 5: Data processing device, 5-1: Data collection unit, 5-2: Pass / fail judgment unit, 5-3
... Data storage unit, 5-4 ... Trend calculation unit, 5-5 ... Trend calculation prediction unit, 6 ... Input switch, 7 ... Simulation input device, agen
t… Intelligent mobile agent.

Continuing on the front page (72) Inventor Mamoru Kato 1 Toshiba-cho, Fuchu-shi, Tokyo In the Fuchu office of Toshiba Corporation (72) Inventor Goichi Sawai 1-1-1, Shibaura, Minato-ku, Tokyo In the head office of Toshiba Corporation ( 72) Inventor Ryuji Tanaka 1 Toshiba-cho, Fuchu-shi, Tokyo F-term in Fuchu Works, Toshiba Corporation (reference) 5G042 FF02 FF03 FF07 FF15 FF23 FF24 FF31

Claims (3)

[Claims] 1. A digital protection system which samples an analog electric quantity input from a power system at a constant period, converts it into a digital quantity, performs a filtering process, and then performs a protection operation based on a predetermined protection operation program. In the inspection method of the relay device, a plurality of the digital protection relay devices were prepared, and each digital protection relay device calculated a relay determination unit for outputting a protection calculation result and an input electric quantity by the same calculation method. It is provided with an electricity quantity sending section for outputting the result, electricity quantity sent from these electricity quantity sending sections is collected by a common data collecting means via a signal transmission path, and the collected data is inputted to a pass / fail judgment section. Inspection method for digital protection relays that makes a failure judgment using an arithmetic expression for good or bad. 2. A simulated input device, comprising: a deficient amount of electricity detection unit that operates when an analog amount of electricity input from a power system is equal to or less than a predetermined value; a simulated input device; 2. The inspection method of the digital protection relay device according to claim 1, further comprising an input switching unit that operates so as to switch to the input device and take in the simulated input. 3. A judgment result storage means for storing past data of a judgment value obtained by the quality judgment unit,
The system is characterized in that the stored past judgment value is compared with a judgment value at the time of the latest inspection, and a defect judgment or a sign of a defect is detected based on a trend of the judgment data. 2. The inspection method of the digital protection relay device according to 1.