Protection control system and protection control method

Abstract

To perform an operation test for each unit in a distributed protection control system device.SOLUTION: A protection control system includes a merging unit, and a protection control device connected to the merging unit via a communication network. When a signal indicating an amount of electricity of a power system is input, the merging unit converts the amount of electricity into digital data to output the digital data to a communication network. The protection control device receives the digital data regarding the amount of electricity from the communication network and executes protection control operation to output a digital command corresponding to results of the protection control operation to the communication network. The merging unit receives the digital command to output a control command based on the digital command to facilities of the power system. The protection control device includes a local output unit that outputs results of the protection control operation to a local communication path different from the communication network.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a protection relay system applying a process bus and a test method thereof.

Background Art

[0002] In recent digitalized new protection control systems, mainly consist of an (IED) device that performs arithmetic processing of protection control and a (MU) device that captures analog signals and outputs control commands, and the communication between devices is processed by communication signals, becoming a distributed system. However, due to its dispersion, when using a "test device" that tests the response output signal from the test input of the protection relay operation, device testing can only be performed during combined operation. To test individual devices, it is necessary to conduct tests using dedicated test inputs and output signals.

[0003] As a technology related to a test method for a distributed protection control system, for example, there is one described in Japanese Patent Application Laid-Open No. 2013-165591 (Patent Document 1). Patent Document 1 describes that "the test setting unit generates test setting information indicating that the integrated unit setting and display device has set the integrated unit to a testable state. The communication interface unit of the integrated unit sends the test setting information and electrical quantity information to the protection unit side via the process bus. The relay arithmetic unit of the protection unit receives and combines the test setting information and the electrical quantity information, which is system information, and executes a relay arithmetic test. A protection unit display device is connected to the process bus and the protection unit, and the test setting information is displayed on this device."

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In conventional protection and control systems, when conducting actual equipment tests of an "integrated or bundled protection and control system," there was a "test device" that output a test signal from the test equipment and took in the output of the operational results of the test subject to perform test measurements.

[0006] In contrast, modern digital protection and control systems primarily consist of a distributed system where the IED (Input Device Deposition) unit, which performs the calculations for protection and control, and the MU (Master Unit) unit, which acquires analog signals and outputs control commands, are located at separate sites and connected by a communication network. In such a distributed system, where communication between devices is limited to communication signals, existing "test equipment" cannot perform operational tests on each individual device in the conventional analog signal-based test equipment environment.

[0007] Patent Document 1, mentioned above, proposes a test method that uses communication testing on the interface between two devices to transmit electrical quantity information with a test flag attached, and captures control commands with the test flag attached to perform the test. However, this method requires specifications for handling dummy data with the test flag attached to both devices, so testing may not be possible in cases where dummy data communication is not supported, such as when combining with existing equipment or in multi-vendor combinations where the opposing device uses products from other companies. Furthermore, in real-world testing, existing equipment may be connected to the communication network that performs communication on the interface between the two devices, so it may be desirable to avoid sending dummy information for testing into the communication network. [Means for solving the problem]

[0008] To solve at least one of the above problems, the present invention provides a protection control system comprising a merging unit and a protection control device connected to the merging unit via a communication network, wherein the merging unit, upon receiving a signal indicating the amount of electricity in a power system, converts the amount of electricity into digital data and outputs the digital data to the communication network; the protection control device receives the digital data of the amount of electricity from the communication network, performs a protection control calculation, and outputs a digital command to the communication network according to the result of the protection control calculation; the merging unit receives the digital command and outputs a control command based on the digital command to the equipment of the power system; and the protection control device has a local output unit that outputs the result of the protection control calculation to a local communication path different from the communication network. The test is then performed based on the result of the protection control calculation output by the local output unit to the local communication path, and the control command output by the merging unit when it receives a digital command corresponding to the result of the protection control calculation. It is characterized by the following: [Effects of the Invention]

[0009] According to one aspect of the present invention, even in a distributed protection and control system device for a digital substation where communication between devices is conducted via communication, unit-by-unit operation testing can be performed using a conventional test device that uses end-to-end signals, which input analog current and voltage signals and detect control output signals.

[0010] Furthermore, there is no need to send unnecessary dummy test data to the actual operating environment network.

[0011] Furthermore, even when using a compatible device that only supports actual operation, such as a device from another company, it is possible to perform tests in a real environment. This allows for troubleshooting during installation tests and when using devices from other companies.

[0012] Other issues, configurations, and effects not mentioned above will be clarified by the following description of the embodiments. [Brief explanation of the drawing]

[0013] [Figure 1]This is an explanatory diagram showing an example of a test environment for a protective control system according to an embodiment of the present invention. [Figure 2] This is an explanatory diagram showing an example of an actual operation test covering the entire protection control device and merging unit in a protection control system test environment according to an embodiment of the present invention. [Figure 3] This is an explanatory diagram showing an example of a monitor operation test targeting a protection control device and a merging unit in a protection control system test environment according to Embodiment 1 of the present invention. [Figure 4] This is an explanatory diagram showing an example of a monitor operation test targeting only the protection control device in the protection control system test environment of Embodiment 1 of the present invention. [Figure 5] This is an explanatory diagram showing an example of the internal processing of a protective control device in a test environment of the protective control system according to Embodiment 2 of the present invention. [Figure 6] This is an explanatory diagram showing an example of the internal processing of the local output section of a protection control device in a test environment of a protection control system according to Embodiment 2 of the present invention. [Figure 7] This flowchart shows an example of processing in a test environment for a protective control system embodiment of the present invention. [Modes for carrying out the invention]

[0014] In this embodiment of the present invention, a LOCAL output terminal for testing is provided on the IED (Improvised Emergency Device) side, and a monitor output unit for test response is provided by extracting signals during operation. This makes it possible to perform relay testing on a single IED during replacement using conventional testing equipment. Furthermore, by ensuring that the data handled by the IED's "local output unit" is the same as the data handled by the protection calculation unit handled by the actual "transmission data processing unit," it is ensured that the test measurement is a response result from the same processing as the actual operation. The details of this embodiment will be described below.

[0015] Figure 1 is an explanatory diagram showing an example of a test environment for a protective control system according to an embodiment of the present invention.

[0016] As shown in Fig. 1, a protection control system for a digital substation is configured by connecting a protection control device (IED) 101 and a merging unit (MU) 111 using a process bus 121, and performing communication-based exchanges between devices in a distributed manner. Each part of this protection control system is configured as follows.

[0017] The merging unit (MU) 111 takes in current and voltage signals from the analog input unit 112, converts the current and voltage signals into digital data in the sampling processing unit 113, creates transmission data in the communication control unit 114, and outputs the transmission data. The transmission data transfers the current and voltage signals to the protection control device (IED) 101 via the process bus 121. The protection control device (IED) 101 has its communication control unit 102 receive the data, perform received data processing in the received data processing unit 103, perform protection calculations in the protection calculation unit 104, and issue a control command if the conditions for issuing a control command are met. When issuing a control command, the transmission data processing unit 105 creates transmission data and transfers the control command from the communication control unit 102 to the merging unit (MU) 111 via the process bus 121. The merging unit (MU) 111 performs received data processing to extract control command information from the data received by the communication control unit 114, transfers the information to the input / output signal processing unit 115 to perform input / output signal processing, and outputs a control command from the drive circuit unit 116.

[0018] To test the protection control system composed of this protection control device (IED) 101 and the merging unit (MU) 111, a test device 131 equipped with a variable test output unit 132 outputs test current and voltage signals and applies them to the analog input unit 112 of the system. The current and voltage signal levels of the test output of the test device 131 are varied, and the test device 131 captures the output of the control signal when the protection control system responds at its detection input unit 133 to conduct a relay operation test.

[0019] The general data flow and respective processing times at that time will be described with reference to Fig. 7.

[0020] FIG. 7 is a flowchart showing an example of processing in the protection control system test environment of an embodiment of the present invention.

[0021] The processing flow of FIG. 7 is as described with reference to FIG. 1.

[0022] Here, the processing time T1 is the time required from the start (i.e., the output of the test current and voltage signals from the test device 131) until the signal capture process 701 by the analog input unit 112 of the merging unit (MU) 111, the sampling process 702 by the sampling processing unit 113, and the transmission data output 703 by the communication control unit 114 are completed. The next processing time T2 is, in addition to the processing time T1, the time required from when the protection control device (IED) 101 receives the data until the received data processing 704 by the received data processing unit 103, the protection calculation process 705 and determination 706 by the protection calculation unit 104, and the creation / output 707 of the transmission data by the transmission data processing unit 105 are completed. Finally, the processing time T3 is, in addition to the processing time T2, the time required from when the communication control unit 114 of the merging unit (MU) 111 receives the data including the control command again and performs the received data processing 708, until the input / output signal processing / output 709 is performed by the input / output signal processing unit 115 and the drive circuit unit 116 to drive the switch.

[0023] FIG. 2 is an explanatory diagram showing an example of an actual operation test for the entire protection control device (IED) 101 and the merging unit (MU) 111 in the protection control system test environment of an embodiment of the present invention.

[0024] For example, the test device 131 may measure the time from when the test output unit 132 transmits a test current / voltage signal until the test output from the monitor output unit 143 is input to the detection input unit 133 as processing time T2, and the time from when the test output unit 132 transmits a test current / voltage signal until the output from the drive circuit unit 116 is input to the detection input unit 133 (or the time from when the test output unit 132 transmits a test current / voltage signal until the test output from the monitor output unit 117 is input to the detection input unit 133) as processing time T3. These processing times can be used, for example, to determine whether an abnormality in the protection control system is in the protection control device (IED) 101 or the merging unit (MU) 111.

[0025] The test is performed by inputting the system response result to the test output from the test device 131 into the detection input unit 133 of the test device 131, as shown by the thick arrow 201 in Figure 2, and observing the signal flow. [Examples]

[0026] Embodiment 1 of the present invention will be described with reference to Figures 3 and 4. The system configuration according to Embodiment 1 is the same as the system shown in Figures 1, 2, and 7, unless otherwise specified below.

[0027] Figure 3 is an explanatory diagram showing an example of a monitor operation test targeting the protective control device (IED) 101 and the merging unit (MU) 111 in the protective control system test environment of Embodiment 1 of the present invention.

[0028] The test shown in Figure 3 is performed by outputting a test output from the monitor output unit 117 within the merging unit (MU) 111, which is equipped with a drive circuit, instead of outputting control commands from the actual drive circuit unit 116.

[0029] This is an embodiment that can be implemented when the settings of the merging unit (MU) 111 are changed for testing purposes, and the output is not driven by the drive circuit section 116 connected to the switch, but instead the test can be performed using the monitor output section 117.

[0030] In the configuration shown in Figure 3, the control command output signal from the drive circuit section 116 and the response result output from the monitor output section 117, which are response result outputs of the merging unit (MU) 111, are mutually exclusive.

[0031] Figure 4 is an explanatory diagram showing an example of a monitor operation test targeting only the protective control device (IED) 101 in the protective control system test environment of Embodiment 1 of the present invention.

[0032] Figure 4 shows an example of a test performed on only the protective device (IED) 101 in the configuration shown in Figure 3, where the merging unit (MU) 111 is from another company, the existing unit cannot be modified for testing, or the settings are not to be modified for testing.

[0033] As shown in Figure 4, the test support device 141 is connected to the local output unit 106 of the protective device control unit (IED) 101. The protective device control unit (IED) 101 outputs a control command output from the local output unit 106, which is then transmitted to the local input unit 142 of the test support device 141, outputting a test result from the monitor output unit 143, and the test is performed by capturing the response result at the detection input unit 133 of the test device 131.

[0034] Here, the local output unit 106 has the function of outputting digital data of protection control commands based on the calculation results of the protection calculation unit 104 to the local input unit 142 of the test support device 141 via a local communication path different from the process bus 121. For example, the local output unit 106 may consist of hardware for an interface connected to the local communication path and software for controlling that interface.

[0035] The local input unit 142 of the test support device 141 receives digital data of protection control commands from the local communication path. The monitor output unit 143 generates a monitor signal based on the protection control commands received by the local input unit 142 and outputs it as a test output. The monitor output unit 143 may be configured with hardware and software having the same functionality as the monitor output unit 117 of the merging unit (MU) 111.

[0036] The monitor signal generated here is the signal input to a waveform measuring device (e.g., an oscilloscope). This is the signal that would be output from the monitor output unit 117 if a protection control command based on the calculation result of the protection calculation unit 104 were sent to the merging unit (MU) 111, and the merging unit (MU) 111 were operating normally. A comparison of these monitor signals can be used to isolate and test the operation of the protection control device (IED) 101 and the merging unit (MU) 111, respectively.

[0037] In the configuration shown in Figure 4, the control command output, which is the response result output of the protection device (IED) 101, will be either a control command output based on data from the communication control unit 102 or a control command output from the monitor output unit 143. By exclusively switching between these outputs, it is prevented that the control command output during the operational test will be output to the actual power system.

[0038] In this way, by connecting the operational outputs for each case, such as the case in Figure 3 and the case in Figure 4, to the detection input unit 133 of the test device 131, it is possible to switch between each test using the same test device, thereby enabling individual testing even if there are constraints on the test setting conditions for one of the distributed systems. [Examples]

[0039] Example 2 will be described with reference to Figures 5 and 6. The system configuration of Example 2 is the same as the system shown in Figures 1 to 4 and Figure 7, unless otherwise specified below.

[0040] Figure 5 is an explanatory diagram showing an example of the internal processing of the protective control device (IED) 101 in a protective control system test environment according to Embodiment 2 of the present invention.

[0041] Specifically, Figure 5 is an internal processing block diagram of the part of the protection control device (IED) 101 that passes the output from the protection calculation unit 104 to the local output unit 106 and the transmission data processing unit 105. Unlike Example 1, in Example 2, the local output unit 106 and the transmission data processing unit 105 are not mutually exclusive, and both can output. In addition, a shared memory system is adopted for the internal relay part that passes signals. This ensures that the test operation is performed by referencing the same data in the shared memory 107.

[0042] Figure 6 is an explanatory diagram showing an example of the internal processing of the local output unit 106 of the protection control device (IED) 101 in a test environment of the protection control system of Embodiment 2 of the present invention.

[0043] According to Embodiment 2, as shown in Figure 6, a test can be performed to compare the test monitor output from the monitor output unit 143 of the protection control device (IED) 101 with the test monitor output from the monitor output unit 117 of the merging unit (MU) 111.

[0044] Furthermore, the system of the embodiment of the present invention may be configured as follows.

[0045] (1) A protection control system comprising a merging unit (e.g., a merging unit (MU) 111) and a protection control device (e.g., a protection control device (IED) 101) connected to the merging unit via a communication network (e.g., a process bus 121), wherein when the merging unit receives a signal indicating the amount of electricity in the power system, it converts the amount of electricity into digital data and outputs the digital data to the communication network; the protection control device receives the digital data of the amount of electricity from the communication network, performs a protection control calculation, and outputs a digital command to the communication network according to the result of the protection control calculation; the merging unit receives the digital command and outputs a control command based on the digital command to the equipment in the power system; and the protection control device has a local output unit (e.g., a local output unit 106) that outputs the result of the protection control calculation to a local communication path different from the communication network (e.g., a communication path between a local output unit 106 and a local input unit 142).

[0046] This allows for operational testing of individual units, such as merging units and protective control devices, in a distributed protection and control system.

[0047] (2) The protection control system described in (1) above, further comprising a test support device (e.g., test support device 141) connected to the local communication path, wherein the test support device generates and outputs a monitor signal to be input to a waveform measuring device (e.g., an oscilloscope) based on the result of the protection control calculation (e.g., processing by the monitor output unit 143).

[0048] This allows for unit-by-unit operational testing in a distributed protection and control system.

[0049] (3) The protection control system described in (2) above, wherein the test support device generates the control command to be output as the monitor signal when the merging unit receives a digital command corresponding to the result of the protection control calculation.

[0050] This allows for unit-by-unit operational testing in a distributed protection and control system.

[0051] (4) The protection control system described in (3) above, wherein the protection control device further has a shared memory (e.g., shared memory 107) for storing the results of the protection control calculation, outputs a digital command corresponding to the results of the protection control calculation read from the shared memory to the communication network, and the local output unit outputs the results of the protection control calculation read from the shared memory to the local communication path.

[0052] This ensures that the same data is used to test each unit.

[0053] (5) The protection control system described in (4) above, further comprising a test device (e.g., test device 131), the test device having a test output unit (e.g., test output unit 132) that outputs a test signal indicating the amount of electricity of the power system, and a detection input unit (e.g., detection input unit 133) into which the control command and the monitor signal are input, and measuring a first time (e.g., processing time T2) from the time the test signal is output until the monitor signal is input, and a second time (e.g., processing time T3) from the time the test signal is output until the control command is input.

[0054] This helps in identifying abnormal parts within the protective control system.

[0055] It should be noted that the present invention is not limited to the embodiments described above, and various modifications are included. For example, the embodiments described above are explained in detail for a better understanding of the present invention, and are not necessarily limited to those having all of the configurations described. Furthermore, it is possible to replace parts of the configuration of one embodiment with the configuration of another embodiment, and it is possible to add configurations from other embodiments to the configuration of one embodiment. In addition, it is possible to add, delete, or replace parts of the configuration of each embodiment with other configurations.

[0056] Furthermore, each of the above configurations, functions, processing units, and processing means may be implemented in hardware, either partially or entirely, by designing them as integrated circuits, for example. Alternatively, each of the above configurations and functions may be implemented in software by a processor interpreting and executing programs that implement each function. Information such as programs, tables, and files that implement each function can be stored in storage devices such as non-volatile semiconductor memory, hard disk drives, and SSDs (Solid State Drives), or in computer-readable non-temporary data storage media such as IC cards, SD cards, and DVDs.

[0057] Furthermore, the control lines and information lines shown are those deemed necessary for explanation purposes, and do not necessarily represent all control lines and information lines in the actual product. In practice, it can be assumed that almost all components are interconnected. [Explanation of symbols]

[0058] 101 Protective Devices (IEDs) 102 Communication Control Unit 103 Received Data Processing Unit 104 Protection calculation section 105 Transmission Data Processing Unit 106 Local Output Section 107 Shared Memory 111 Merging Unit (MU) 112 Analog Input Section 113 Sampling Processing Unit 114 Communication Control Unit 115 Input / Output Signal Processing Unit 116 Drive circuit section 117 Monitor Output Section 121 process bus 131 Test equipment 132 Variable Test Output Unit 133 Detection Input Section 141 Test support equipment 142 Local Input Section 143 Monitor Output Section

Claims

1. A protection control system comprising a merging unit and a protection control device connected to the merging unit via a communication network, When the merging unit receives a signal indicating the amount of electricity in the power system, it converts the amount of electricity into digital data and outputs the digital data to the communication network. The protection control device receives digital data of the electrical quantity from the communication network, performs a protection control calculation, and outputs a digital command to the communication network according to the result of the protection control calculation. The merging unit receives the digital command and outputs a control command based on the digital command to the equipment of the power system. The protection control device has a local output unit that outputs the result of the protection control calculation to a local communication path different from the communication network. A protection control system characterized by performing a test based on the result of the protection control calculation output by the local output unit to the local communication path and the control command output by the merging unit when it receives a digital command corresponding to the result of the protection control calculation.

2. A protective control system according to Claim 1, The aforementioned protective control device is The system further includes a shared memory for storing the results of the protection control calculation, A digital command corresponding to the result of the protection control calculation read from the shared memory is output to the communication network. The protection control system is characterized in that the local output unit outputs the result of the protection control calculation read from the shared memory to the local communication path.

3. A protective control system according to Claim 1, The system further includes a test support device connected to the local communication path, The aforementioned test support device is a protection control system characterized by generating and outputting a monitor signal to be input to a waveform measuring device based on the result of the protection control calculation.

4. The protective control system according to claim 3, The aforementioned test support device is a protection control system characterized in that it generates the control command to be output as the monitor signal when the merging unit receives a digital command corresponding to the result of the protection control calculation.

5. A protective control system according to claim 4, The test equipment is further equipped, The aforementioned test apparatus is It has a test output unit that outputs a test signal indicating the amount of electricity in the power system, and a detection input unit that receives the control command and the monitor signal. A protective control system characterized by measuring a first time from the time the test signal is output until the monitor signal is input, and a second time from the time the test signal is output until the control command is input.

6. A protection control method performed by a protection control system, The protection control system comprises a merging unit and a protection control device connected to the merging unit via a communication network. The aforementioned protection control method is, The merging unit, upon receiving a signal indicating the amount of electricity in the power system, performs a first step of converting the amount of electricity into digital data and outputting the digital data to the communication network. The protection control device receives digital data of the electrical quantity from the communication network, performs a protection control calculation, and outputs a digital command to the communication network according to the result of the protection control calculation, The protection control device performs a third step of outputting the result of the protection control calculation to a local communication path different from the communication network, A fourth step in which the merging unit receives the digital command and outputs a control command based on the digital command to the equipment of the power system, A protection control method characterized by including a fifth step of performing a test based on the result of the protection control calculation output to the local communication path and the control command output by the merging unit when it receives a digital command corresponding to the result of the protection control calculation.

7. A protection control method according to claim 6, The protection control device further includes a shared memory for storing the results of the protection control calculation, In the second step, the protection control device outputs a digital command corresponding to the result of the protection control calculation read from the shared memory to the communication network. A protection control method characterized in that, in the third step, the protection control device outputs the result of the protection control calculation read from the shared memory to the local communication path.

8. A protection control method according to claim 6, The protection control system further comprises a test support device connected to the local communication path, The protection control method further includes a sixth step in which the test auxiliary device generates and outputs a monitor signal to be input to the waveform measuring device based on the result of the protection control calculation.

9. A protection control method according to claim 8, A protection control method characterized in that, in the sixth step, the test support device generates the control command to be output as the monitor signal when the merging unit receives a digital command corresponding to the result of the protection control calculation.

10. A protection control method according to claim 9, The aforementioned protection control system further comprises a test device, The test apparatus includes a test output unit that outputs a test signal indicating the amount of electricity in the power system, and a detection input unit that receives the control command and the monitor signal. The protection control method further includes a seventh step of measuring a first time from when the test device outputs the test signal until the monitor signal is input, and a second time from when the test signal is output until the control command is input.

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