Process Interface Unit and Power System Protection and Control System

Abstract

To provide a novel PIU (Process Interface Unit) with high reliability.SOLUTION: An interface unit provides information on a current or a voltage acquired from an instrument transformer provided in electric facilities to a protection device or a control device connected with a communication line. The interface unit has a calculation part, a first output circuit, and a second output circuit. The first output circuit outputs to a circuit breaker a command for controlling the circuit breaker to be in an open state in a case where both a first open signal and a second open signal outputted from the calculation part are inputted, or in a case where both a third open signal and a fourth open signal are inputted. The second output circuit outputs to the circuit breaker a command for controlling the circuit breaker to be in an energization state in a case where both a first energization signal and a second energization signal outputted from the calculation part are inputted, or in a case where both a third energization signal and a fourth energization signal are inputted.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] This paper relates to protective devices that detect and eliminate accidents in electrical equipment, such as power transmission lines, switches such as circuit breakers, and transformers, and to control electrical equipment, as well as control devices that monitor and control electrical equipment, and to power system protection and control systems that are composed of these devices. [Background technology]

[0002] Conventionally, protection and control devices (hereinafter sometimes referred to as protection and control devices) installed in substations obtain system current and voltage information, status information and fault information of electrical equipment such as switches such as circuit breakers and transformers via metal cables. Metal cables were also used for the control output from the protection and control devices to the switches and electrical equipment. Protection and control devices are installed in each piece of electrical equipment such as power transmission lines, and are digital devices that use microprocessors and software technology.They generally consist of a calculation unit that performs protection and control processing, an input / output unit that inputs system voltage and current information and electrical equipment status and fault information, and outputs control information to switches and electrical equipment, and a transmission unit that performs transmission processing with a higher-level device. Meanwhile, with recent technological advances, protection and control systems that use process buses are beginning to be put into practical use. In this system, the input and output sections in a conventional protection and control device are separated and made independent as process interface units (hereafter referred to as PIUs), and the two are connected by communication using optical cables. This communication path is called the process bus. The PIU is sometimes called a merging unit (MU). Conventionally, protection and control devices and electrical equipment were connected by metal cables, but in this system, a PIU is installed near the electrical equipment, and the PIU takes in system current and voltage information, as well as electrical equipment status and fault information, converts it into digital form, and sends the digital information to the protection and control device via the process bus, or receives control output commands for the electrical equipment from the protection and control device via the process bus and outputs control to the controlled equipment. By applying a process bus, a protection and control system can significantly reduce the amount of metal cable within a substation, which can run for several hundred kilometers depending on the size of the substation, by using optical cable instead of metal cable.This is expected to result in reduced cable space and substation area, as well as a reduced environmental impact. On the other hand, the input / output section of the conventional protection and control device will be separated and an independent PIU will be installed to implement the input / output section, which will increase the number of devices compared to conventional systems. Depending on the system construction concept, a configuration in which a PIU is provided for each protection and control device is also considered, and a further increase in the number of devices is expected. This will result in a significant increase in the number of devices that make up the system compared to conventional systems, which will lead to issues such as a more complex system configuration, worsening economic efficiency, and reduced reliability. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-70769 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention aims to provide a new, highly reliable PIU that has an optimal system configuration and an optimal output circuit configuration, taking into consideration the above-mentioned problems, for protection and control systems that use process buses, which are expected to be used in the future. As a solution to the increasing number of devices and the complexity of the system configuration, the present invention provides a PIU that can be shared by protection and control devices within an electrical facility such as a power transmission line, or by other devices, thereby simplifying the system configuration.In addition, the present invention provides a highly reliable PIU by implementing a means to maintain performance equivalent to that of conventional systems, avoid malfunctions due to PIU defects, and avoid output operation delays during automatic inspection of the output circuit. [Means for solving the problem]

[0005] A PIU (Process Interface Unit) according to an embodiment provides information on current or voltage or both obtained from an instrument transformer installed in an electrical facility such as a power transmission line, and information on the status of electrical facility such as a circuit breaker, to a protection device or a control device connected via a communication line, or to both the protection device and the control device. The PIU has a calculation unit, a first output circuit, and a second output circuit. The calculation unit obtains a first open signal, a second open signal, a first energization signal, or a second energization signal transmitted by the protection device in accordance with the status of the electrical facility, obtains a third open signal, a fourth open signal, a third energization signal, or a fourth energization signal transmitted by the control device in accordance with the status of the electrical facility or an operation by an operator, outputs the obtained first open signal, the second open signal, the third open signal, or the fourth open signal to the first output circuit, and outputs the obtained first energization signal, the second energization signal, the third energization signal, or the fourth energization signal to the second output circuit. The first output circuit outputs a command to the circuit breaker to control the circuit breaker to an open state when both the first open signal and the second open signal are input, or when both the third open signal and the fourth open signal are input. The second output circuit outputs a command to the circuit breaker to control the circuit breaker to an energized state when both the first energization signal and the second energization signal are input, or when both the third energization signal and the fourth energization signal are input. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of a substation system 1. [Diagram 2] 1 is a diagram mainly showing a protection device 32, a control device 42, a PIU 50, and electrical equipment E. [Diagram 3] FIG. 2 is a diagram showing an example of the functional configuration of a calculation unit 60. [Figure 4] FIG. 2 is a diagram showing an example of the functional configuration of an output circuit 80 and an output circuit 82. [Diagram 5] FIG. 4 is a diagram for explaining a protection device 32X, a control device 42Y, and a circuit breaker 100 of a comparative example. [Figure 6]FIG. 13 is a diagram showing an example of the functional configuration of a PIU 50A according to a second embodiment. [Figure 7] FIG. 4 is a diagram for explaining the processing executed by a processing unit 68. [Figure 7A] FIG. 13 is a diagram for explaining another type of processing executed by the processing unit 68. [Figure 8] FIG. 13 is a diagram showing an example of the configuration of a substation system 1A according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, the PIU of the embodiment will be described with reference to the drawings.

[0008] First Embodiment 1 is a diagram showing an example of the configuration of a substation system 1 including a PIU. In this embodiment, a substation is used as an example, but the substation system 1 of this embodiment may be applied to a power station that handles a power receiving and transforming system of a power plant, a switchyard, a factory, or a general industry instead of the substation.

[0009] The substation system 1 is divided into a station level hierarchy, a bay level hierarchy, and a process level hierarchy, and is composed of devices and equipment provided at the station level, devices and equipment provided at the bay level, devices and equipment provided at the process level, and communication lines CL1, CL2, etc. that connect these devices. The bay level is a hierarchy between the station level and the process level.

[0010] [Station level] At the station level, for example, a TC (Telecommunicate Equipment) 12, an HMI (Human Machine Interface) 14, and a first communication line CL1 are provided. The first communication line CL1 (first network) may be referred to as a station bus, for example. The first communication line CL1 is a communication line that constitutes a LAN (Local Area Network) in a predetermined area in the substation. Note that the TC 12, the HMI 14, and the communication line CL1 may each be partially or entirely made redundant.

[0011] The TC 12 is connected to the first communication line CL1. The TC may also be referred to as a GW (Gateway). The TC 12 is a device that relays the transmission and reception of acquired information. The acquired information is information acquired from devices and equipment connected to the first communication line CL1. The TC 12 is a device that relays communication with devices (e.g., the HMI 14) installed within the substation and outside the substation (e.g., computer systems in facilities outside the substation such as a system control center or a power supply station). The HMI 14 may be configured to communicate directly with each device (e.g., a protection device or a control device) within the substation, rather than via the TC 12, to collect information within the substation.

[0012] The HMI 14 is connected to the TC 12. The HMI 14 and the TC 12 may be connected via, for example, a dedicated line. The HMI 14 includes, for example, a display unit, and displays information collected by the TC 12 on the display unit. The display unit displays, for example, the operating status of devices and equipment (circuit breakers and transformers) included in the substation system 1, and the electric quantities (current, voltage, active / reactive power) of electrical facilities such as transmission lines. By referring to the information displayed on the display unit, an operator can check the status of the devices and equipment of the substation system 1 and the operating status of the substation system 1, and can also give control commands to the devices and equipment. The above control commands control the use / locking of devices and the opening / closing of circuit breakers.

[0013] [Bay Level] At the bay level, for example, a control panel 40 and a protection panel 30 are provided. The control panel 40 is arranged for the purpose of monitoring and controlling and measuring equipment such as power transmission lines. The control panel 40 receives equipment control commands for circuit breakers and the like (not only circuit breakers but also disconnectors and earth disconnectors) from the TC 12 and the HMI 14, transmits the received equipment control commands to the PIU 50, and the PIU 50 issues equipment control commands to the circuit breakers and the like to be controlled to control opening and closing of the equipment. The PIU 50 also takes in an AC electric quantity from an instrument transformer, converts it into a digital value, transmits the digitally converted AC electric quantity to the control panel 40, and transmits the digitally converted AC electric quantity to the TC 12 or the HMI 14 via the control panel 40. Note that the control panel 40 may be prepared separately for each device to be controlled (for example, a control panel for a power transmission line, a control panel for a transformer, a control panel for a busbar, etc.). The control panel may also be made redundant.

[0014] The protection panel 30 takes in the digitally converted AC electricity quantity from the PIU 50 and performs system fault calculations (e.g., current differential relay calculations, etc.), and if the calculation results indicate a system fault, the protection panel 30 sends a command to the PIU 50 to shut off the circuit breaker. The PIU 50 outputs a command to the circuit breaker to open it. Note that a protection panel 30 may be prepared separately for each device to be protected (e.g., a protection panel for power transmission lines, a protection panel for transformers, a protection panel for busbars, etc.). In addition, the protection panels may be made redundant.

[0015] The control device 42 mounted on the control panel 40 and the protection device 32 mounted on the protection panel are sometimes called IEDs (Intelligent Electrical Devices). The control panel 40 and the protection panel 30 will be described below in that order.

[0016] The control panel 40 is connected to the first communication line CL1 and the second communication line CL2. The control panel 40 includes a control device (e.g., BCU; Bay Control Unit, etc.) 42. The control device 42 is provided for each piece of power equipment, such as a line that supplies power to a load and a transformer that converts a system voltage, in the substation, and monitors and controls the power equipment. The control device 42 acquires equipment status (opening and closing information) of equipment such as a circuit breaker, a disconnecting switch, a grounding device, etc., electric quantity information, and information on various equipment failures from the PIU 50 provided in the power equipment to be monitored, and handles information for monitoring and controlling the operation status of the power equipment, such as a transmission line, based on the acquired information. The electric quantity information is information on the power supplied to a section of the power equipment, and is, for example, information indicating the voltage value and current value of the power supplied to the section. The equipment status information is information on the operation of a circuit breaker, a disconnecting switch, a disconnecting switch with a grounding switch, etc. controlled by the control panel 40 or the protection panel 30, and is, for example, information indicating whether the circuit breaker, etc. is in a connected state or a disconnected state. The fault information is fault information of various devices arranged in the power facility. The control device 42 transmits the generated various information to the TC 12 and the like.

[0017] The control device 42 acquires, for example, information on the state of the system in the power facility such as a line and the state of various facilities from devices and equipment connected to the first communication line CL1 and the second communication line CL2. Furthermore, the control device 42 can control the opening and closing of switches such as circuit breakers and disconnectors for changing the configuration of the system in the power facility based on the results of its own calculations or instructions from an operator.

[0018] The protection board 30 includes a protection device 32. The protection board 30 is connected to a first communication line CL1 and a second communication line CL2. The second communication line CL2 may be provided as a redundant line.

[0019] The second communication line CL2 (second network) may be referred to as, for example, a process bus. The second communication line CL2 is a communication line that constitutes a LAN (Local Area Network) in a specific area such as a substation. Hereinafter, the first communication line CL1 may be referred to as a "station bus," and the second communication line CL2 may be referred to as a "process bus."

[0020] Here, for example, the first communication protocol of the first communication line CL1 is different from the second communication protocol of the second communication line CL2. For example, the communication protocol of the first communication line CL1 is a communication protocol of a station bus applied to the IEC 61850 standard, and the communication protocol of the second communication line CL2 is a communication protocol of a process bus applied to the IEC 61850 standard. The communication protocol of the first communication line CL1 and the communication protocol of the second communication line CL2 are not limited to the above communication protocols and may be other communication protocols, or the communication protocol of the first communication line CL1 and the communication protocol of the second communication line CL2 may be the same. There is also a case where both the first communication line CL1 and the second communication line CL2 are configured redundantly.

[0021] The protective panel 30 is a protective relay device that controls circuit breakers provided at multiple locations in electrical equipment, such as power transmission lines, that are installed in the power system. When an accident, such as a short circuit or a ground fault, occurs in the power system, the protective panel 30 shuts off the circuit breakers to isolate the power equipment or system where the accident occurred, thereby eliminating the accident and preventing the accident from spreading, thereby ensuring the sound operation of the power system.

[0022] The protection panel 30 acquires power information related to the power supplied to the section to be protected. The protection panel 30 generates operation information related to the operation of the circuit breaker, and controls the circuit breaker based on the generated operation information. The protection panel 30 transmits the power information and operation information to the control device 42, the TC 12, etc.

[0023] [Process level] The process level is provided with a PIU50. The PIU50 is connected to a second communication line CL2. The PIU50 is an example of an interface unit with electrical equipment such as an instrument transformer, a switchgear, and a transformer. In the case of following the system construction concept of a conventional substation system before the application of a process bus, a dedicated PIU50 may be provided for each protection and control device. In this case, however, the number of devices increases, resulting in problems such as a complicated system configuration, a worsening of economy, and a decrease in reliability. Therefore, in this embodiment, the PIU is shared between the protection device 32 and the control device 42. Note that the second communication line CL2 and the PIU50 may be partially or entirely made redundant.

[0024] The PIU 50 provides information on current or voltage obtained from an instrument transformer installed in electrical equipment such as a power transmission line to the protection device 32 and control device 42 connected to the process bus. The PIU 50 obtains information indicating the status of equipment and information on equipment failures. The PIU 50 is connected to equipment such as an instrument transformer and a circuit breaker connected to a power transmission line, etc. The PIU 50 obtains information obtained by the instrument transformer and the status of equipment such as circuit breakers, and transmits the obtained information to the protection panel 30 and control panel 40. The PIU 50 converts the system electrical quantity input from the instrument transformer into a digital signal and transmits the converted digital signal to the protection device 32.

[0025] FIG. 2 is a diagram mainly showing the protection device 32, the control device 42, the PIU 50, and the electrical equipment E.

[0026] [Protective device] The protection device 32 includes, for example, a fault detection unit 34 and a reclosing control unit 36. The fault detection unit 34 detects the presence or absence of a fault in the section to be protected, for example, by using information on the power equipment (for example, current and voltage information) acquired from the PIU 50. For example, the fault detection unit 34 detects the presence or absence of a fault in the protection section by using main detection elements such as a current differential element and a distance relay element. When a fault in the protection section is detected based on the main detection elements, a signal (hereinafter referred to as "signal (M)") generated by the fault detection unit 34 is output as a first opening signal.

[0027] The fault detection unit 34 detects the presence or absence of a fault based on, for example, information on the power equipment acquired from the PIU 50 (for example, information on current and voltage). The fault detection unit 34 detects the presence or absence of a fault using fault detection elements such as an overcurrent element and an undervoltage element, regardless of the protection section. When a fault is detected based on the fault detection elements, the fault detection unit 34 generates and outputs a signal (hereinafter referred to as "signal (FD)") as a second open signal. The above-mentioned generation method of the signal (M) and the signal (FD) is an example, and other methods may be used. For example, the signal (M) and the signal (FD) are generated by different generation methods, and for example, the generation method of the signal (FD) is a signal generated by a simpler calculation than the generation method of the signal (M). The signal (M) may be output as the second open signal, and the signal (FD) may be output as the first open signal. The fault detection unit 34 may be divided into a main detection element related to the signal (M) and a fault detection element related to the signal (FD).

[0028] When the reclosing control unit 36 ​​recognizes that the conditions for the circuit breaker 100 to be closed without any abnormality, such as the gas pressure of the circuit breaker 100 being equal to or higher than a predetermined level, it generates a reclosing preparation completion signal and outputs the generated preparation completion signal as a first energization signal. After a voltage-free time during which the fault is expected to be cleared has elapsed since an opening command was output to the circuit breaker 100, the reclosing control unit 36 ​​outputs a reclosing command signal as a second energization signal after confirming that the elements related to the voltage of the target system have been synchronized as necessary. The preparation completion signal may be output as the second energization signal, and the reclosing command signal may be output as the first energization signal. Note that the reclosing control unit 36 ​​may be divided into a section for generating the preparation completion signal and a section for generating the reclosing command signal.

[0029] [Control device] The control device 42 includes, for example, a control command unit 44. The control command unit 44 controls electrical equipment of a system under its jurisdiction based on its own calculation results or an instruction from an operator. For example, when opening a circuit breaker, if the control command unit 44 receives an equipment selection command from the TC 12 or the HMI 14 or generates an equipment selection command based on its own calculation results, the control command unit 44 generates a selection signal (open) indicating that the equipment to be controlled has been selected or has been selected, and outputs the generated selection signal (open) as a third open signal. Also, for example, when opening a circuit breaker, if the control command unit 44 receives an equipment control command from the TC 12 or the HMI 14 or generates an equipment control command based on its own calculation results, the control command unit 44 generates a control signal (open) for controlling the equipment to be controlled, and outputs the generated control signal (open) as a fourth open signal. For example, when the control command unit 44 energizes a circuit breaker, if the control command unit 44 receives an equipment selection command from the TC 12 or the HMI 14 or generates an equipment selection command based on its own calculation result, the control command unit 44 generates a selection signal (energization) indicating that the equipment to be controlled has been selected or has been selected, and outputs the generated selection signal (energization) as a third energization signal. Also, for example, when the control command unit 44 energizes a circuit breaker, if the control command unit 44 receives an equipment control command from the TC 12 or the HMI 14 or generates an equipment control command based on its own calculation result, the control command unit 44 generates a control signal (energization) for controlling the equipment to be controlled, and outputs the generated control signal (energization) as a fourth energization signal.

[0030] [PIU] The PIU 50 includes, for example, an input conversion unit 52, a signal conversion unit 54, an input circuit 56, a calculation unit 60, an input / output unit 70, an output circuit 80 (an example of a "first output circuit"), an output circuit 82 (an example of a "second output circuit"), and a transmission unit 90. The input conversion unit 52 removes noise and the like contained in an analog signal (for example, current, voltage information) transmitted from, for example, an instrument transformer, and converts the signal into a predetermined analog quantity. The signal conversion unit 54 converts the analog signal output by the input conversion unit 52 into a digital signal. The input circuit 56 acquires status information, fault information, and the like output by means of contacts and the like from switches such as circuit breakers and electrical equipment such as transformers, and transmits the information to the input / output unit 70. The input / output unit 70 acquires the signal output to the calculation unit 60 and outputs the acquired signal to the output circuit 80 or the output circuit 82. The transmission unit 90 is a communication interface for communicating with various devices and equipment. In the following description, of the functional components included in the PIU 50, the arithmetic unit 60, the output circuit 80, and the output circuit 82 will be mainly described, and illustrations of the other functional components will be omitted hereafter.

[0031] The calculation unit 60 processes input signals and inspects output circuits. FIG. 3 is a diagram showing an example of the functional configuration of the calculation unit 60. The calculation unit 60 includes, for example, an analog signal processing unit 61A, a binary signal processing unit 61B, a switching command unit 62, a protection control command discrimination unit 64, and an automatic inspection processing unit 66. The switching command unit 62, the protection control command discrimination unit 64, and the automatic inspection processing unit 66 are realized by a hardware processor such as a CPU (Central Processing Unit) executing a program (software). In addition, some or all of these functional units may be realized by hardware (including circuitry) such as an LSI (Large Scale Integration), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a GPU (Graphics Processing Unit), or may be realized by cooperation between software and hardware. The program may be stored in advance in a storage device such as an HDD (Hard Disk Drive) or flash memory (a storage device with a non-transient storage medium), or may be stored in a removable storage medium (non-transient storage medium) such as a DVD or CD-ROM, and installed in the storage device by inserting the storage medium into a drive device.

[0032] The analog signal processing unit 61A acquires the signal output from the signal conversion unit 54 and transmits the acquired signal to the protection device 32 or the control device 42 using the transmission unit 90 as an interface, for example, by a method such as an SV (Sampled Value) signal specified in IEC 61850.

[0033] The binary signal processing unit 61B acquires the signal output from the input / output unit 70, and transmits the acquired signal to the protection device 32 or the control device 42 using the transmission unit 90 as an interface, for example, by a method such as a GOOSE (Generic Object Oriented Substation Events) signal specified in IEC 61850.

[0034] The switching command unit 62 acquires each signal output by the protection device 32 or the control device 42, and outputs the acquired signal to the output circuit 80 or the output circuit 82. The switching command unit 62 outputs the signal to the output circuit 80 or the output circuit 82 so that the signal is input to the contact of the output circuit 80 or the contact of the output circuit 82 according to the type of the signal.

[0035] The protection control command discriminator 64 discriminates whether the acquired signal is a signal output by the protection device 32 or a signal output by the control device 42. When the protection control command discriminator 64 receives a command from the protection device 32, it locks the command from the control device 42. When the protection control command discriminator 64 receives a command from the protection device 32 while receiving a command from the control device 42, the protection control command discriminator 64 prioritizes the command from the protection device 32.

[0036] The automatic inspection processing unit 66 inspects whether or not there is an abnormality in the output circuit 80 and the output circuit 82. The automatic inspection processing unit 66 outputs a first inspection signal, which will be described later, to the output circuit 80, acquires information indicating the operating state of the output circuit 80 according to the first inspection signal from the output circuit 80, and judges whether or not the output circuit 80 operates normally (first inspection process). The automatic inspection processing unit 66 outputs a second inspection signal, which will be described later, to the output circuit 82, acquires information indicating the operating state of the output circuit 82 according to the second inspection signal from the output circuit 82, and judges whether or not the output circuit 82 operates normally (second inspection process). The automatic inspection processing unit 66 outputs the first inspection signal or the second inspection signal at a predetermined timing to perform the inspection process. The automatic inspection processing unit 66 periodically outputs the first inspection signal or the second inspection signal to perform the inspection process. The automatic inspection processing unit 66 may generate the first inspection signal or the second inspection signal upon receiving an instruction to generate the first inspection signal or the second inspection signal from the control device 42. The inspection signal may be output at any timing other than a predetermined timing, for example, by manual activation.

[0037] In the following description, of the functional components included in the calculation unit 60, the switching command unit 62, the protection control command discrimination unit 64, and the automatic inspection processing unit 66 will be mainly described, and illustrations of the other functional components will be omitted hereafter.

[0038] The output circuit 80 controls the circuit breaker 100 from a conducting state to an open state and inspects its own circuit based on the signal instruction output by the calculation unit 60. The output circuit 82 controls the circuit breaker 100 from an open state to a conducting state and inspects its own circuit based on the instruction of the protection device 32 or the control device 42 input via the calculation unit 60.

[0039] FIG. 4 is a diagram showing an example of the functional configuration of the output circuit 80 and the output circuit 82. The output circuit 80 includes, for example, a contact A, a contact B, and a first inspection unit. In the case of operation by the protection device 32, when a signal (M) is input, the contact A is controlled to change from an open state to a conductive state. When a signal (FD) is input, the contact B is controlled to change from an open state to a conductive state. In the case of operation by the control device 42, when a selection signal (open) is input, the contact A is controlled to change from an open state to a conductive state. When a control signal (open) is input, the contact B is controlled to change from an open state to a conductive state. When the contacts A and B are controlled to a conductive state, the output circuit 80 outputs a signal (open command) to the circuit breaker to control the circuit breaker to an open state. When the above signal (open command) is input, the circuit breaker controls the circuit breaker to an open state. As described above, when both the signal (M) and the signal (FD) or both the selection signal (open) and the control signal (open) are input, the output circuit 80 controls the circuit breaker 100 to the open state.

[0040] The first inspection unit is normally in a conducting state, and when a first inspection signal is input, it controls the inspection contacts included in the first inspection unit to an open state. When an operation check signal for checking the operation of contact A or contact B is input to contact A or contact B while the inspection contacts are controlled to be in an open state, contact A or contact B will open or conduct electricity. This allows the operation of contact A or contact B to be checked.

[0041] The output circuit 82 includes, for example, a contact C, a contact D, and a second inspection unit. In the case of operation by the protection device 32, when a preparation completion signal is input, the contact C is controlled to change from an open state to an energized state. When a reclose command signal is input, the contact D is controlled to change from an open state to an energized state. In the case of operation by the control device 42, when a selection signal (energized) is input, the contact C is controlled to change from an open state to an energized state. When a control signal (energized) is input, the contact D is controlled to change from an open state to an energized state. When the contacts C and D are controlled to an energized state, the output circuit 82 outputs a signal (close command) to the circuit breaker to control the circuit breaker to an energized state (closed state). When the above signal (close command) is input, the circuit breaker controls the circuit breaker to an energized state (closed state). As described above, when both the preparation completion signal and the reclose command signal, or both the selection signal (energized) and the control signal (energized) are input, the output circuit 82 controls the circuit breaker 100 to the energized state.

[0042] The second inspection unit is normally in a conducting state, and when an inspection signal is input, it controls the inspection contacts included in the second inspection unit to an open state. When an operation check signal for checking the operation of contact C or contact D is input to contact C or contact D while the inspection contacts are controlled to be in an open state, contact C or contact D changes the contact to an open state or a conducting state. This allows the operation of contact C or contact D to be checked.

[0043] Here, a protection device 32X, a control device 42Y, and a circuit breaker 100 in a comparative example will be described with reference to Fig. 5. In the comparative example, the protection device 32X and the circuit breaker 100X, and the control device 42Y and the circuit breaker 100X are directly connected by a communication line such as a metal cable. Also, no PIU is provided between the protection device 32X and the circuit breaker 100X, and no PIU is provided between the control device 42Y and the circuit breaker 100X.

[0044] Furthermore, the protection device 32X includes a fault detection unit 34X, a switching circuit control unit 36X, an output circuit 80X, and an output circuit 82X. The control device 42X includes a control command unit 44Y, an output circuit 80Y, and an output circuit 82Y. As described above, the output circuit and the protection device 32X, and the output circuit and the control device 42X are provided in the same device. The protection device 32X and the control device 42Y each output a signal to the circuit breaker to directly control the circuit breaker.

[0045] Here, in recent years, digitalization in electric power stations has progressed, and digital substations in which PIUs are installed near electrical equipment such as instrument transformers (VTs / CTs), switches, and transformers, information is collected in the PIU, and standards such as IEC 61850, which is an international standard, are applied between the PIU, the protection device, and the control device, are being put into practical use. However, the configuration shown in FIG. 5 may not be appropriate for a digital substation system. For example, in order to reduce the cost of the hardware of the PIU, it is preferable to implement a shared output circuit for the protection device and the control device. In addition, when the output circuit is shared, it is necessary to consider how to handle commands from each device and when a fault occurs, and facilities that can maintain the same reliability as the current situation are required. In this embodiment, as described above, by implementing a shared output circuit, it is possible to provide a highly reliable facility while realizing the required functions and suppressing costs.

[0046] According to the first embodiment described above, a PIU 50 having an arithmetic unit 60, an output circuit 80, and an output circuit 82 is provided within a substation system 1 in a form that can be commonly used for the protection device 32 and the control device 42, or other devices. In addition, the PIU 50 is provided with a means for processing commands from the protection device 32 in preference to commands from the control device 42. This makes it possible to provide a highly reliable PIU having performance equivalent to that of conventional systems, and an optimal protection and control system configuration when a process bus is applied, thereby providing a solution to the issues of protection and control systems when a process bus is applied.

[0047] <Second embodiment> The second embodiment will be described below. In the second embodiment, the protection device and the control device share the PIU, the PIU includes two sets of output units, and further has a function of switching the output units to be used. The second embodiment will be described below, focusing on the differences from the first embodiment.

[0048] 6 is a diagram showing an example of the functional configuration of the PIU 50A of the second embodiment. The PIU 50A includes, for example, a calculation unit 60A. In addition to the functional configuration of the first embodiment, the PIU 50A includes an output circuit 84 and an output circuit 86. The output circuit 84 has a functional configuration similar to that of the output circuit 80, and the output circuit 86 has a functional configuration similar to that of the output circuit 82.

[0049] The calculation unit 60A includes a processing unit 68 in addition to the functional configuration of the calculation unit 60 of the first embodiment. The processing unit 68 is realized by a hardware processor such as a CPU executing a program (software). The processing unit 68 may be realized by hardware (including circuitry) such as an LSI, ASIC, FPGA, or GPU, or may be realized by a combination of software and hardware. The calculation unit 60A includes an analog signal processing unit 61A and a binary signal processing unit 61B, which are omitted in FIG. 6.

[0050] The processing unit 68 determines whether or not an abnormality has occurred in the output circuit 80 or the output circuit 82, and if an abnormality has occurred, outputs a signal that was to be output to the output circuit in which the abnormality has occurred to an output circuit having a similar functional configuration to the output circuit in which it has been determined that the abnormality has occurred. If an abnormality has occurred in the output circuit 80 or the output circuit 82, the processing unit 68 stops use of the output circuit in which the abnormality has occurred, and controls the breaker 100 using an output circuit having a similar functional configuration to the output circuit in which the abnormality has occurred. Furthermore, if the output circuit 80 or the output circuit 82 is being inspected, the processing unit 68 controls the breaker 100 using an output circuit having a similar functional configuration to the output circuit being inspected.

[0051] 7 is a diagram for explaining the process executed by the processing unit 68. For example, when the output circuits 80 and 82 are used and the output circuits 84 and 86 are not used, if an abnormality occurs in the output circuit 80, the processing unit 68 stops using the output circuit 80 and switches to using the output circuit 84 having a similar functional configuration. Note that, when the output circuit 80 or the output circuit 82 is used and an abnormality occurs in one or both of the output circuits 80 and 82, the processing unit 68 may stop using the output circuits 80 and 82 and use the output circuits 84 and 86. Similarly, when the output circuit 80 or the output circuit 82 is being inspected, the processing unit 68 may switch to using the output circuit 84 or the output circuit 86.

[0052] Also, in a state where the output circuits 84 and 86 are used and the output circuits 80 and 82 are not used, a switch may be made so that if an abnormality occurs in the output circuit 84, the output circuit 80 is used, and if an abnormality occurs in the output circuit 86, the output circuit 82 is used. Similarly, when the output circuit 84 or the output circuit 86 is undergoing inspection, a switch may be made so that the output circuit 80 or the output circuit 82 is used.

[0053] The output circuits may be switched not only in a manner in which only output circuits that are abnormal or under inspection are switched, but also in a manner in which, when a certain output circuit is abnormal or under inspection, all circuits that are not abnormal or under inspection are switched at once.

[0054] For example, when the output circuit 80 is abnormal or undergoing inspection and the output circuit 82 is not abnormal or undergoing inspection, only the output circuit 80 may be switched to the output circuit 84, and the output circuit 82 may not be switched. In addition, when the output circuit 80 is abnormal or undergoing inspection and the output circuit 82 is not abnormal or undergoing inspection, the output circuits 80 and 82 may be switched to the output circuits 84 and 86, respectively.

[0055] 7A is a diagram for explaining another method of processing executed by the processing unit 68. For example, in a state where the output circuit 80 and the output circuit 82 are used for the protection device, and the output circuit 84 and the output circuit 86 are used for the control device, if an abnormality occurs in the output circuit 80, the processing unit 68 stops using the output circuit 80 and switches to using the output circuit 84 having a similar functional configuration in common for the protection device and the control device. Also, for example, if an abnormality occurs in the output circuit 82, the processing unit 68 stops using the output circuit 82 and switches to using the output circuit 86 having a similar functional configuration in common for the protection device and the control device. Similarly, the output circuit 80 may be used in common when the output circuit 84 is abnormal, and the output circuit 82 may be used in common when the output circuit 86 is abnormal. Similarly, output circuit 84 may be used in common when output circuit 80 is under inspection, output circuit 86 may be used in common when output circuit 82 is under inspection, output circuit 80 may be used in common when output circuit 84 is under inspection, and output circuit 82 may be used in common when output circuit 86 is under inspection. Also, output circuits 80 and 82 may be used for control devices, and output circuits 84 and 86 may be used for protection devices.

[0056] According to the second embodiment described above, the substation system 1 can provide a highly reliable system by including the output circuits 84 and 86 in addition to the output circuits 80 and 82. For example, even if the output circuit 80 or the output circuit 82 is under inspection, the inspection process can be temporarily suspended, and the circuit breaker 100 can be controlled using another output circuit without waiting for the output process while the output circuit 80 or the output circuit 82 is being restored to a normal use state. In addition, even if the output circuit 84 or the output circuit 86 is under inspection, the circuit breaker 100 can be controlled using another output circuit. Similarly, even if an abnormality occurs in the output circuit 80 or the output circuit 82, or if an abnormality occurs in the output circuit 84 or the output circuit 86, the circuit breaker 100 can be controlled using the other output circuit. Therefore, even if an abnormality occurs in the output circuit or during inspection, the circuit breaker can be quickly controlled to cut off without delaying or suppressing delay from the specified cutoff time, and delay in cutting off can be avoided, and a highly reliable PIU 50 and a protection control system with an optimal configuration when a process bus is applied can be provided.

[0057] <Third embodiment> The third embodiment will be described below. In the third embodiment, a plurality of PIUs 50 cooperate with each other to control the circuit breaker. The third embodiment will be described below, focusing on the differences from the first embodiment.

[0058] FIG. 8 is a diagram showing an example of the configuration of a substation system 1A of the third embodiment. The substation system 1A includes, for example, a PIU 50-1 and a PIU 50-2. The PIU 50-1 acquires a signal output by the protection device 32 and a signal output by the control device 42, selects the signal output by the protection device 32 from the acquired signals, and controls the circuit breaker 100 based on the signal output by the protection device 32. The PIU 50-2 acquires a signal output by the protection device 32 and a signal output by the control device 42, selects the signal output by the control device 42 from the acquired signals, and controls the circuit breaker 100 based on the signal output by the control device 42. Based on the above processing as a rule, when an abnormality occurs or during inspection processing, the following processing is performed.

[0059] When an abnormality occurs in output circuit 80-1 or output circuit 82-1, or during inspection processing, PIU 50-1 transmits information indicating that an abnormality has occurred or that inspection is being performed to PIU 50-2. When PIU 50-2 acquires this information, it controls breaker 100 by using an output circuit having a similar functional configuration to the output circuit in PIU 50-1 in which an abnormality has occurred or which is being inspected. PIU 50-2 may also have the same functions as PIU 50-1 which performs the above-mentioned processing.

[0060] For example, when an abnormality occurs in the PIU 50-1, the PIU 50-1 transmits information indicating the occurrence of the abnormality to the PIU 50-2 using a predetermined communication protocol (for example, GOOSE; Generic Object Oriented Substation Event defined in IEC 61850). When the PIU 50-2 acquires information regarding the abnormality from the PIU 50-1, the PIU 50-2 controls itself so as to control the circuit breaker 100 based on the signal output from the control device 42 and the signal output from the protection device 32. When an abnormality occurs, instead of (in addition to) the PIU 50-1 may be controlled to a state in which the PIU 50-2 can control the circuit breaker 100 based on the signal output from the control device 42 and the signal output from the protection device 32 as described above while the PIU 50-1 is being inspected. Also, the PIU 50-1 is controlled to a state in which the PIU 50-1 can control the circuit breaker 100 based on the signal output from the protection device 32 and the signal output from the control device 42 while the PIU 50-2 is being inspected or when an abnormality occurs.

[0061] Furthermore, if an abnormality occurs in PIU 50-1 (for example, if an abnormality occurs in the output circuit), and PIU 50-1 acquires a signal for controlling the circuit breaker 100 from the protection device 32, the acquired signal may be transferred to PIU 50-2, which may then execute processing in accordance with the transfer. Furthermore, if an abnormality occurs in PIU 50-2, the signal may be transferred to PIU 50-1, which may then execute processing in accordance with the transfer.

[0062] In addition to switching only the output circuit that is abnormal or under inspection, the output circuits may also be switched collectively when an output circuit is abnormal or under inspection. For example, when the output circuit 80 is abnormal or under inspection and the output circuit 82 is not abnormal or under inspection, only the output circuit 80 is switched to the output circuit 84, and the output circuit 82 is not switched. In addition, when the output circuit 80 is abnormal or under inspection and the output circuit 82 is not abnormal or under inspection, the output circuits 80 and 82 may be switched to the output circuit 84 and the output circuit 86.

[0063] According to the third embodiment described above, even if the substation system 1A is configured with a PIU 50-1 that mainly handles signals from the protection device 32 and a PIU 50-2 that mainly handles signals from the control device 42, it is possible to construct a highly reliable protection and control system by having means for transferring abnormal conditions and inspection conditions to each other and having means for functioning as a commonly usable PIU in abnormal conditions and inspection conditions.

[0064] In the configuration of Figure 8, for example, even if PIU50-1 is used commonly for protection and control and PIU50-2 is normally left unused as standby, a highly reliable protection and control system can be constructed by using the same means as described above.

[0065] The second and third forms may also be combined.

[0066] In the first, second and third embodiments, the PIU may be, for example, a PIU having a protection function, a control function and the like, or in addition, a PIU connected to a station bus in addition to a process bus, for example.

[0067] According to each of the embodiments described above, a more reliable protection device can be realized.

[0068] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope of the invention and its equivalents described in the claims, as well as in the scope and spirit of the invention. [Explanation of symbols]

[0069] 1... substation system, 30... protection panel, 32... protection device, 40... control panel, 42... control device, 50... PIU, 60... calculation unit, 80, 82, 84, 86... output circuit

Claims

1. An interface unit that provides information on current or voltage or both obtained from an instrument transformer installed in the electrical equipment and information on the status of the electrical equipment obtained from the electrical equipment to a protection device or a control device, or both of the protection device and the control device, connected to a communication line, The device includes a calculation unit, a first output circuit, and a second output circuit, The calculation unit is Obtaining a first open signal, a second open signal, a first energization signal, or a second energization signal transmitted by the protection device according to a state of the electrical equipment; acquiring a third open signal, a fourth open signal, a third energization signal, or a fourth energization signal transmitted by the control device in response to a state of the electrical equipment or an operation by an operator; outputting the acquired first open signal, the second open signal, the third open signal, or the fourth open signal to the first output circuit; outputting the acquired first energization signal, the second energization signal, the third energization signal, or the fourth energization signal to the second output circuit; the first output circuit outputs a command to the circuit breaker to control the circuit breaker to an open state when both the first open signal and the second open signal are input, or when both the third open signal and the fourth open signal are input, the second output circuit outputs a command to the circuit breaker to control the circuit breaker to a conductive state when both the first energization signal and the second energization signal are input, or when both the third energization signal and the fourth energization signal are input, Process Interface Unit.

2. a third output circuit including a functional configuration similar to or equivalent to the first output circuit; a fourth output circuit including a functional configuration similar to or equivalent to the second output circuit; The calculation unit is determining whether an abnormality has occurred in the first output circuit or the second output circuit or whether an output circuit is being inspected; When an abnormality occurs in the first output circuit or when the first output circuit is being inspected, the first open signal, the second open signal, the third open signal, or the fourth open signal is output to the third output circuit instead of the first output circuit; When an abnormality occurs in the second output circuit or when the second output circuit is being inspected, the first energization signal, the second energization signal, the third energization signal, or the fourth energization signal is output to the fourth output circuit instead of the second output circuit. The process interface unit of claim 1 .

3. The calculation unit prioritizes processing based on a signal transmitted by the protection device over processing based on a signal transmitted by the control device.

3. The process interface unit according to claim 1 or 2.

4. The calculation unit executes a first inspection process for inspecting an operation of the first output circuit and a second inspection process for inspecting an operation of the second output circuit. A process interface unit according to any one of claims 1 to 3.

5. the protection device and the control device are connected to a process bus and a station bus; the interface unit is connected to the process bus and communicates with the protection device and the control device via the process bus; A process interface unit according to any one of claims 1 to 4.

6. A plurality of interface units for providing information on a current or voltage obtained from an instrument transformer provided in the electrical equipment and information on a state of the electrical equipment obtained from the electrical equipment to a protection device or a control device or both connected to a communication line, a first interface unit included in the plurality of interface units connected to the communication line, A first calculation unit, a first output circuit, and a second output circuit, The first calculation unit is Obtaining a first open signal, a second open signal, a first energization signal, or a second energization signal transmitted by the protection device according to a state of the electrical equipment; outputting the acquired first open signal or the acquired second open signal to the first output circuit; outputting the acquired first energization signal or the acquired second energization signal to the second output circuit; the first output circuit outputs a command to the circuit breaker to control the circuit breaker to an open state when both the first open signal and the second open signal are input; the second output circuit outputs a command to the circuit breaker to control the circuit breaker to a conductive state when both the first energization signal and the second energization signal are input; A second interface unit included in the plurality of interface units includes: a second calculation unit, a third output circuit, and a fourth output circuit; The second calculation unit is acquiring a third open signal, a fourth open signal, a third energization signal, or a fourth energization signal transmitted by the control device in response to a state of the electrical equipment or an operation by an operator; outputting the acquired third open signal or the acquired fourth open signal to the first output circuit; outputting the acquired third energization signal or the acquired fourth energization signal to the second output circuit; the third output circuit outputs, when both the third open signal and the fourth open signal are input, a command to the circuit breaker to control the circuit breaker to an open state; the fourth output circuit outputs, when both the third energization signal and the fourth energization signal are input, a command to control the circuit breaker to a conductive state, to the circuit breaker; Process Interface Unit.

7. The first calculation unit is When an abnormality occurs in the first output circuit, the acquired signal or information indicating the occurrence of the abnormality is transmitted to the second interface unit; The second calculation unit executes the process that was to be performed by the first calculation unit, instead of the first calculation unit, by using the third output circuit. The process interface unit of claim 6.

8. 8. A power system protection and control system comprising the process interface unit according to claim 1 as a component.

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