JP2012182905A - Diagnostic apparatus for protective relay - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce burden on both owners of distributed power sources and an administrating firm of a power system so as to secure safety of the power system when operating a protective relay.SOLUTION: A slave station 9 performs an operation test (self-diagnosis) of an interconnection protective relay 54 according to data received from a key station 3 through a relay station 4. In doing so, the slave station 9 outputs a switch signal to a magnet switch MGS2 to connect a test switch SW1 to a terminal T2, and a test switch SW2 to a terminal T4. Then, after the slave station 9 outputs pseudo abnormal values to the interconnection protective relay 54, according to whether the slave station 9 receives a trip signal from the interconnection protective relay 54 or not, the slave station 9 transmits a test result indicating normal or abnormal to the key station 3 through the relay station 4. Meanwhile, the interconnection protective relay 54, after receiving the pseudo abnormal values from the slave station 9, detects an abnormality and transmits a trip signal to the slave station 9. After the completion of the test on the relay, the slave station 9 connects the test switch SW1 to a terminal T1, and the test switch SW2 to a terminal T3 by a switch signal.

Description

  The present invention relates to a self-diagnosis function of a protective relay using a transfer interrupting device in a distributed power transfer interrupting system.

  Due to the recent eco-boom, subsidy system to support the introduction of power generation equipment, surplus power purchase system, etc., solar power generation equipment, wind power generation equipment and power storage equipment (hereinafter referred to as “power generation equipment”) are spreading. Many power generation facilities are being installed.

  When generating power by connecting the power generation equipment to the power grid, it is based on the “Grid Grid Technical Requirements Guidelines for Ensuring Power Quality” established by the Agency for Natural Resources and Energy and the “Grid Grid Regulations” to supplement those guidelines. Power plant owners or managers (hereinafter referred to as “customers”) and power system managers (hereinafter referred to as “system managers”) conduct prior consultations on power quality and safety measures, and are necessary. Is required to confirm that appropriate measures have been taken.

  One necessary measure is the installation and management of protective relays. The protective relay has a control function of detecting a short-circuit failure or the like and disconnecting the failure section from the power system, and customers are required to manage the protective relay appropriately in the future. However, since the protective relay has a feature of “operating when in an emergency”, its management tends to be neglected.

JP 2011-4458 A

Therefore, in the past, matters relating to protective relays are described in contracts (for example, contract outlines for surplus power received from solar power generation) signed between customers and system managers. There's a problem.
(1) For the system administrator, it takes a lot of time and manpower to gather inspection histories and to request regular inspections from customers.
(2) For the customer, time and expense burdens arise in the maintenance of the equipment.
(3) Some customers do not read the contract, and some reject the inspection.
(4) There is a time lag between the occurrence of a device failure and contact with the system administrator, and the safety of the power system during that time is not guaranteed.
In addition, Patent Document 1 discloses a power monitoring system that performs a protection characteristic test of a protection relay mounted on a distribution board without any main circuit power failure. However, the protection relay checks the operation of a circuit breaker. Yes, it does not confirm the operation of the protection relay itself from the outside.

  The present invention has been made in view of the above-mentioned problems, and its main purpose is to reduce the burden on both the installer of the distributed power source and the manager of the power system when operating the protective relay, and to ensure the safety of the power system. It is to ensure sex.

  In order to solve the above-described problems, the present invention provides an open / close connected between the power system and the distributed power source when it is determined that the power system or the distributed power source connected to the power system is abnormal. A protective relay diagnostic device for diagnosing a protective relay that outputs a cut-off signal instructing a circuit to open, a first connection state in which the protective relay is connected to the measuring instrument of the power system and the switch, Or, the switching means for switching the second connection state in which the protective relay and the protective relay diagnostic device are connected, and the abnormal value related to the power system is simulated in the state switched to the second connection state by the switching means. When the interruption signal is output from the protection relay and then the interruption signal is acquired from the protection relay, the protection relay is determined to be normal, and the interruption signal is not acquired from the protection relay. A diagnostic means for determining that the protective relay is abnormal, and an administrator notification means for notifying the apparatus of the power system when the diagnostic relay determines that the protective relay is abnormal by the diagnostic means; And a return means for switching to the first connection state by the switching means after the diagnosis of the protection relay by the diagnostic means is completed.

  According to this configuration, the protective relay connected to the measuring instrument and the switch at normal times is connected to the diagnostic device at the time of diagnosis, and an abnormal value is pseudo-output from the diagnostic device, and a shut-off signal is returned. By determining whether or not, it is possible to diagnose whether or not the protective relay is normal without bothering manpower and without affecting the interconnection of the power system and the distributed power source. Further, when the protection relay determines that there is an abnormality, the fact is notified to the system administrator's device, so the system administrator can respond without delay from the occurrence of the abnormality. According to the above, when operating the protective relay, the burden on both the installer of the distributed power source and the manager of the power system can be reduced, and the safety of the power system can be ensured.

Further, in the protection relay diagnostic device of the present invention, aside from the protection relay, system abnormality determination means for determining whether or not the power system is abnormal, and while the protection relay is switched to the second connection state In addition, when the power system is determined to be abnormal by the system abnormality determination unit, an abnormality recovery unit that switches to the first connection state by the switching unit may be further provided.
According to this configuration, when an abnormality occurs in the power system while the protective relay is not connected to the measuring instrument of the power system for diagnosis, the abnormality is detected by the diagnostic device, and the protective relay is normally connected. Return to the current connection. According to this, it is possible to diagnose the protective relay while monitoring the state of the power system, and when a power system abnormality occurs, the switch is opened by the function of the protective relay, and the distributed power supply is shut off be able to.

In the protection relay diagnosis device of the present invention, the protection relay may be diagnosed when an instruction for diagnosis of the protection relay is obtained from a device of the power system manager.
According to this configuration, the manager of the power system can instruct diagnosis of the protective relay at an arbitrary timing.

In the protection relay diagnosis apparatus of the present invention, a diagnosis schedule of the protection relay may be stored, and the protection relay may be diagnosed according to the schedule.
According to this configuration, the customer can perform diagnosis of the protective relay according to the diagnosis schedule by setting the diagnosis schedule in the diagnosis device in advance.

In the protection relay diagnosis apparatus of the present invention, the protection relay may be diagnosed when an instruction for diagnosis of the protection relay is acquired by an operation of a field worker.
According to this configuration, the local worker can instruct diagnosis of the protective relay at an arbitrary timing.

  In addition, the problems disclosed by the present application and the solutions thereof will be clarified by the description of the mode for carrying out the invention and the drawings.

  ADVANTAGE OF THE INVENTION According to this invention, when operating a protection relay, the burden of both the installation person of a distributed power supply and the manager of an electric power system can be eased, and the safety | security of an electric power system can be ensured.

It is a figure which shows the structure of the transfer interruption | blocking system 1 for distributed power supplies. 1 is a diagram illustrating a configuration of a transfer cutoff signal transmission device (master station) 3. FIG. It is a figure which shows the structure of the power conditioner 5 and its periphery. 3 is a diagram showing a configuration of a slave station 9. FIG. It is a figure which shows the structure of the data memorize | stored in the memory | storage part of each apparatus, (a) shows the structure of the customer information 34A memorize | stored in the memory | storage part 35 of the master station 3, (b) is the memory | storage of the slave station 9 The structure of the slave station information 94A stored in the unit 94 is shown. It is a figure which shows the format of the data transmitted / received between the main | base station 3 and the sub_station | mobile_unit 9, (a) shows the format of test switch switching data, (b) shows the format of relay test data. 4 is a flowchart showing relay test processing of the master station 3. It is a flowchart which shows the data reception process of the sub_station | mobile_unit 9.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The slave station (protective relay diagnosis device) according to the embodiment of the present invention receives a predetermined trigger, temporarily disconnects the interconnection protection relay (protection relay) from the power system, and diagnoses the operation of the interconnection protection relay. Is to implement. Necessary when the master station (transfer cutoff signal transmission device) on the system administrator side acquires the diagnosis result of the interconnection protection relay from the slave station (transfer cutoff device) and the diagnosis result indicates an abnormality. The system of the distributed power supply is disconnected accordingly. That is, in the embodiment of the present invention, the operation of the interconnection protection relay is diagnosed from the outside by utilizing a distributed power supply transfer cut-off system including a master station and a slave station. According to this, it becomes possible to reduce the burden on the customer and the system administrator and to ensure the safety of the power system when properly managing the protective relay.

≪System configuration and overview≫
FIG. 1 is a diagram showing a configuration of a distributed power transfer cutoff system 1. The distributed power transfer interruption system 1 includes a distribution automation system 2, a transfer interruption signal transmission device (hereinafter referred to as "master station") 3, a transfer interruption signal relay device (hereinafter referred to as "relay station") 4, a power conditioner. 5 and a distributed power source 6. The relay station 4 is provided on the utility pole, and the power conditioner 5 is provided in the customer (electric power consumer) 's house, and they are communicably connected via a service line.

  The distribution automation system 2 manages the state of the power system and transmits power system information to the master station 3 in real time. The master station 3 acquires and stores power system information in advance. Then, when a power system accident occurs, CB (Circuit Breaker) / Ry (Relay: protection relay) information is acquired, and based on the acquired CB / Ry information and stored power system information, a power failure The distributed power source 6 connected to the section of the distributed power line is specified, and a transfer cut-off signal (disconnection request) including the number of the specified distributed power source 6 is sent to the relay station under its control via the IP network 7 4 to send. The relay station 4 stores the number of the distributed power source 6 under its control. When the transfer cutoff signal is received from the master station 3 via the IP network 7, the number of the distributed power source 6 under the relay station 4 is added to the number of the distributed power source 6 to be blocked included in the transfer cutoff signal. Is included, a transfer interruption signal is transmitted to the subordinate power conditioner 5 by PLC (Power Line Communication) using a lead-in line.

  The power conditioner 5 has a function of converting DC power generated by the distributed power supply 6 into household AC power, and receives a transfer cut-off signal from the relay station 4 by a low-speed PLC on the lead-in line, or itself Has a function of detecting a system abnormality and disconnecting the distributed power source 6 from the power system by a built-in switch. The distributed power source 6 is a private power source such as a solar power generator or a wind power generator installed at a customer's home, and is connected to the power system via the power conditioner 5.

  In addition, between the master station 3 and the power conditioner 5, not only the transfer cut-off signal but also data related to the operation diagnosis of the interconnection protection relay built in the power conditioner 5 is transmitted / received via the relay station 4. .

FIG. 2 is a diagram showing a configuration of the transfer cutoff signal transmission device (master station) 3. The master station 3 includes a communication unit 31, a display unit 32, an input unit 33, a processing unit 34, and a storage unit 35, and is configured so that each unit can transmit and receive data via the bus 36. The communication unit 31 is a part that communicates with the distribution automation system 2 and the relay station 4 via a communication line (including the IP network 7), and is realized by a NIC (Network Interface Card) or the like. The display unit 32 is a part that displays data according to an instruction from the processing unit 34, and is realized by, for example, a liquid crystal display (LCD). The input unit 33 is a part where an operator inputs data, and is realized by a keyboard, a mouse, or the like. The processing unit 34 exchanges data between the units and controls the entire master station 3. The processing unit 34 is realized by a CPU (Central Processing Unit) executing a program stored in a predetermined memory. The The storage unit 35 stores data from the processing unit 34 and reads the stored data, and is realized by a nonvolatile storage device such as a flash memory or a hard disk device.
The distribution automation system 2 and the relay station 4 have the same configuration as the master station 3 in FIG.

  FIG. 3 is a diagram showing the configuration of the power conditioner 5 and its periphery. The power conditioner 5 includes an inverter 51 and a switch 52 as an electric main circuit unit, and includes an inverter control circuit 53, a connection protection relay 54, and a slave station 9 as a control circuit unit. The inverter 51 is a device that converts DC power from the distributed power source 6 into AC power, and the converted AC power is supplied to the distribution board 8 via the switch 52. The switch 52 is a switch for causing the distributed power source 6 to be parallel or disconnected from the power system. The switch 52 is connected between the inverter 51 and the distribution board 8 and normally the distributed power source 6 is connected in a closed state. In parallel, when an abnormality in the power system is detected, the distributed power source 6 is disconnected due to an open circuit state.

  The inverter control circuit 53 performs various controls related to the inverter 51 (voltage, current, frequency, maximum power point tracking [MPPT, Maximum Power Point Tracking], single operation detection, voltage rise prevention, sequence, etc.) and abnormalities in the power system. Is detected, the system abnormality information is transmitted to the interconnection protection relay 54. The interconnection protection relay 54 acquires voltage, current, frequency, etc. (system data) of the power system from a measuring instrument (not shown) provided on the power line, and outputs a trip signal when an abnormality is detected. Thus, the distributed power source 6 is disconnected from the power system. A trip signal is also output when system abnormality information is received through the inverter control circuit 53 or when a failure of the distributed power source 6 is detected. Further, the interconnection protection relay 54 is a diagnosis target by the slave station 9.

  The slave station 9 performs an operation diagnosis of the interconnection protection relay 54 (for example, confirmation of an abnormality detection function of voltage and frequency) and a transfer interruption of the distributed power source 6 according to the data received from the master station 3 via the relay station 4. This is a device that performs (a function of a transfer interrupting device in a distributed power transfer interrupting system), and is connected to magnet switches MGS1 and MGS2 and terminals T2 and T4. By outputting a transfer cut-off signal to the magnet switch MGS1, the switch 52 is opened, and the distributed power supply 6 is disconnected. By outputting a test switch switching signal to the magnet switch MGS2, the test switches SW1 and SW2 are connected to the respective terminals according to the normal time and the test of the interconnection protection relay 54. Switch.

  The test switch SW1 is a switch for switching a transmission source of a signal input to the interconnection protection relay 54. Of the terminals whose connection is switched, the terminal T1 is connected to a power line measuring instrument (not shown), and the terminal T2 Is connected to the slave station 9. On the other hand, the test switch SW2 is a switch for switching the destination of the signal output from the interconnection protection relay 54. Of the terminals whose connection is switched, the terminal T3 is connected to the magnet switch MGS1, and the terminal T4 is connected to the slave station 9. Connected.

  Normally, the test switch SW1 is connected to the terminal T1, and the test switch SW2 is connected to the terminal T3. As a result, the interconnection protection relay 54 acquires the system data from the power line and outputs the trip signal as a transfer cutoff signal to the magnet switch MGS1 when the power system abnormality is detected, thereby opening the switch 52. The distributed power source 6 is disconnected. On the other hand, during the relay test, the test switch SW1 is connected to the terminal T2, and the test switch SW2 is connected to the terminal T4. Thereby, the interconnection protection relay 54 acquires a pseudo abnormal value of the power system as a relay test instruction from the slave station 9, detects the abnormality, and outputs a trip signal to the slave station 9 as a relay test result.

  FIG. 4 is a diagram showing the configuration of the slave station 9. The slave station 9 includes a communication unit 91, a signal input / output unit 92, a processing unit 93, and a storage unit 94, and is configured so that each unit can transmit and receive data via the bus 95. The communication unit 91 is a part that communicates with the relay station 4 by PLC, and is realized by a PLC modem or the like. The signal input / output unit 92 outputs signals to the magnet switches MGS1 and MGS2 and the terminal T2 shown in FIG. 3 and acquires signals from the terminal T4. The processing unit 93 exchanges data between the units and controls the slave station 9 as a whole. The processing unit 93 is realized by the CPU executing a program stored in a predetermined memory. The storage unit 94 stores data from the processing unit 93 and reads the stored data, and is realized by a non-volatile storage device such as a flash memory or a hard disk device.

<< Data structure >>
FIG. 5 is a diagram illustrating a configuration of data stored in the storage unit of each device. FIG. 5A shows the configuration of customer information 35 </ b> A stored in the storage unit 35 of the master station 3. The customer information 35A is information relating to the customer's home under the master station 3, and includes a record including a distributed power supply number 35A1, customer contact information 35A2, and a processing result 35A3. The distributed power supply number 35A1 is a number unique to each distributed power supply 6 connected to the subordinate of the master station 3, and is set as data transmitted from the master station 3 to the slave station 9. The customer contact information 35A2 is a contact information of a customer who manages the distributed power supply 6 of the distributed power supply number 35A1, and for example, an address, a telephone number, an e-mail address, etc. are set, and a contact information for contacting the processing result 35A3. Used as The processing result 35A3 is the result of the processing in the slave station 9, and is notified to the customer contact 35A2 when it is abnormal.

  FIG. 5B shows the configuration of the slave station information 94 </ b> A stored in the storage unit 94 of the slave station 9. The slave station information 94A is information related to the slave station 9, and includes a distributed power supply number 94A1, a relay connection mode 94A2, and a processing result 94A3. The distributed power supply number 94A1 is a number unique to the distributed power supply 6 connected to the power conditioner 5 incorporating the slave station 9, and is matched with the distributed power supply number of the data received from the master station 3. Sometimes processing according to the received data is performed. The relay connection mode 94A2 indicates a connection state of the test switches SW1 and SW2 of the interconnection protection relay 54, and a normal mode (first connection state) or a test mode (second connection state) is set. The normal mode is the normal connection state described in FIG. 3 (the test switch SW1 is connected to the terminal T1 and the test switch SW2 is connected to the terminal T3), and the interconnection protection relay 54 is normal. Perform the operation. On the other hand, the test mode is the connection state (the test switch SW1 is connected to the terminal T2 and the test switch SW2 is connected to the terminal T4) at the time of the relay test described with reference to FIG. 54 is an object of the operation test (self-diagnosis). The processing result 94A3 indicates the result of the data reception processing of the slave station 9.

  FIG. 6 is a diagram illustrating a format of data transmitted / received between the master station 3 and the slave station 9. FIG. 6A shows a format of test switch switching data. This data is used when the master station 3 instructs the slave station 9 to switch the test switches SW1 and SW2 of the power conditioner 5 and when the slave station 9 notifies the master station 3 of the result. Used. The packet length is the size of the data, and “20 bytes” is set as a fixed length. The distributed power supply number is the number of the distributed power supply 6 connected to the power conditioner 5 including the interconnection protection relay 54 to be tested. The T flag is “1” during the relay test and “0” during normal operation. As the packet type, “31h” indicating a selection control command (one behavior) is set. The C flag and serial number are fixed to 0. The control code indicates the switching code of the test switch, and is set to “03h” indicating switching to the normal mode or “05h” indicating switching to the test mode. The control response result indicates the switching result of the test switch, and is set to “FFh” indicating normal operation or “0Fh” indicating malfunction. The transmission time (day, hour, minute, second) indicates the time when the data is transmitted from the master station 3 or the slave station 9, and one decimal digit is set for each byte.

  FIG. 6B shows a format of relay test data. The data is used when the master station 3 instructs the slave station 9 to perform the test of the interconnection protection relay 54 and when the slave station 9 notifies the master station 3 of the result. The packet length is the size of the data, and “24 bytes” is set as a fixed length. The distributed power supply number is the number of the distributed power supply 6 connected to the power conditioner 5 including the interconnection protection relay 54 to be tested. The T flag is set to “1” indicating the relay test time. As the packet type, “35h” indicating a relay test is set. The C flag is fixed to 0. The test type indicates the type of relay test, “01h” indicating overvoltage (voltage increase), “02h” indicating undervoltage (voltage drop), “03h” indicating overcurrent, “04h” indicating frequency increase, Alternatively, “05h” indicating a frequency drop is set. The test response indicates the result of the relay test, and is set to a value equal to or greater than “01h” indicating relay operation or “00h” indicating relay non-operation. The test input value is an input value to the interconnection protection relay 54 relay for the relay operation test corresponding to the test type, and a binary number is set for the digital relay. The transmission time (year, month, day, hour, minute) indicates the time when the data is transmitted from the master station 3 or the slave station 9, and one decimal digit is set for each byte.

≪System processing≫
7 and 8 are flowcharts showing the processing of the distributed power supply transfer cutoff system 1. FIG. FIG. 7 shows the relay test process of the master station 3. In the master station 3, in the master station 3, the processing unit 34 mainly refers to and updates the data in the storage unit 35 in response to an instruction from the input unit 33 by the operation of the system administrator, while the communication unit 31 performs the IP network The relay station 4 is instructed to perform a relay test via the relay station 4.

  First, the master station 3 transmits test switch switching data to the slave station 9 in order to switch the interconnection protection relay 54 to the test mode (S701). At that time, the test switch switching data shown in FIG. 6A is set in a predetermined memory. Specifically, one of the distributed power supply numbers 35A1 in the customer information 35A in the storage unit 35 is set as the distributed power supply number. Next, “1” indicating the relay test time is set in the T flag, and “05h” indicating switching to the test mode is set in the control code. Then, the current date and time are set as the transmission time. Note that the fixed value of the test switch switching data is set in advance. Subsequently, test switch switching data is received as a switching result from the slave station 9, the control response result is stored as a processing result 35A3 (S702), and whether or not the control response result is “FFh” indicating normal operation. Is determined (S703).

  If the control response result is “FFh”, that is, if the switching result is normal (Y in S703), the master station 3 transmits relay test data to the slave station 9 in order to perform the test of the interconnection protection relay 54. (S704). At that time, the relay test data shown in FIG. 6B is set on a predetermined memory. Specifically, the distributed power supply number set in the test switch switching data in S701 is set as the distributed power supply number. Next, the instruction value by the operation of the system administrator is set to the test type and the test input value. Then, the current date and time are set as the transmission time. In addition, the fixed value of relay test data shall be preset. Subsequently, the relay test data is received as a test result from the slave station 9, the test response is stored as the processing result 35A3 (S705), and it is determined whether or not the test response is equal to or greater than “01h” indicating the relay operation. (S706).

  If the test response is “01h” or more, that is, if the test result is normal, the master station 3 transmits test switch switching data to the slave station 9 in order to switch the interconnection protection relay 54 to the normal mode (S707). ). At that time, the test switch switching data shown in FIG. 6A is set in a predetermined memory. Specifically, the distributed power supply number set in the relay test data in S704 is set as the distributed power supply number. Next, “0” indicating normal time is set in the T flag, and “03h” indicating switching to the normal mode is set in the control code. Then, the current date and time are set as the transmission time. Note that the fixed value of the test switch switching data is set in advance. Subsequently, test switch switching data is received from the slave station 9 as a switching result, the control response result is stored as a processing result 35A3 (S708), and whether or not the control response result is “FFh” indicating normal operation. Is determined (S709).

  If the control response result is “FFh”, that is, if the switching result is normal (Y in S709), the master station 3 ends the relay test process.

  If the result of switching to the test mode is not normal in S703 (N in S703), if the result of the relay test is not normal in S706 (N in S706), or the result of switching to the normal mode is normal in S709 If it is not (N in S709), the master station 3 considers the importance and urgency of the result, and sends a disconnection request of the distributed power source 6 to the slave station 9 as necessary. The disconnection result is received from the slave station 9 and stored as the processing result 35A3 (S710). It is assumed that the data of the release request and the release result include at least the distributed power source number, the packet type indicating the “release request”, and the release result.

  Then, the master station 3 refers to the customer information 35A, and notifies the processing result 35A3 to the customer contact 35A2 corresponding to the distributed power supply number 35A1 set in the data transmitted to the slave station 9 (S711). In the processing result 35A3, a switching result, a test result, and a disconnection result until it becomes NG are accumulated. According to this, since the customer can know the stage at which the operation is not normal by acquiring and referring to the processing result of the relay test, it is possible to examine future countermeasures. When receiving an inquiry from a customer, the processing result 35A3 corresponding to the distributed power supply number 35A1 or the customer contact address 35A2 may be notified.

  In FIG. 7, as shown in the processing of S704 to S706, the relay test data is transmitted only once from the master station 3, the result for the relay test data is received, and it is determined whether or not it is normal. As described in the description of relay test data in (b), there are five types of tests, from overvoltage to frequency drop, so two or more types of relay test data are transmitted and the results are received. You may make it determine whether or not.

  FIG. 8 shows data reception processing of the slave station 9. In this processing, in the slave station 9, the processing unit 93 mainly receives the data from the master station 3 via the IP network 7 and the relay station 4 by the communication unit 91, and refers to and updates the data in the storage unit 94 while performing the test. Switch switching and relay test.

  First, the slave station 9 determines whether data has been received from the master station 3 (S801). Specifically, it is determined whether or not the communication unit 91 has received data. If the data has been received, the processing unit 93 further determines that the distributed power source number 94A1 in which the distributed power source number in the data is the slave station information 94A. It is determined whether or not it matches. If data having the same distributed power supply number has not been received (N in S801), the reception check is repeated.

  If data having the same distributed power supply number is received (Y in S801), the slave station 9 refers to the packet type and control code in the data, and the data type is switched to the test mode. Then, it is determined whether the instruction is a relay test, switching to the normal mode, or a request for disconnecting the distributed power source 6 (S802).

  When the data type indicates switching to the test mode (test switching in S802), the slave station 9 determines whether or not the relay connection mode 94A2 of the storage unit 94 is in the test mode (S803). If not in the test mode (N in S803), in order to switch to the test mode, the signal input / output unit 92 outputs a test switch switching signal to the magnet switch MGS2 (S804). Then, if the switching of the test switches SW1 and SW2 is normally performed based on the contact information (Y in S805), the test mode is set in the relay connection mode 94A2 of the storage unit 94 (S806). According to this, even if the interconnection protection relay 54 is operated by the relay test instruction via the terminal T2 from the slave station 9, the trip signal reaches the slave station 9 via the terminal T4, and the operation of the switch 52 Since it does not go to the magnet switch MGS1 for use, the distributed power source 6 does not have to be disconnected.

  If the relay connection mode 94A2 is the test mode in S803 (Y in S803), the slave station 9 skips the processes of S804 to S806 because there is no need to switch the test switch. If the test switch is not switched normally in S805 (N in S805), the process in S806 is skipped.

  Then, the slave station 9 transmits the switching result of the test switch to the master station 3 and stores it in the storage unit 94 as the processing result 94A3 (S807). At that time, among the received test switch switching data shown in FIG. 6A, a control response result is set according to the switching result. More specifically, “FFh” is set when the test mode is already set or when the switching is normal. On the other hand, if the switching is not normal, “0Fh” is set. Then, the communication switch 91 transmits test switch switching data to the master station 3. Thereafter, the process returns to S801 to wait for reception of new data.

  When the data type indicates a relay test (test instruction in S802), the slave station 9 determines whether or not the relay connection mode 94A2 of the storage unit 94 is in the test mode (S808). If it is in the test mode (Y in S808), the relay test can be performed, so that the test input value is output as the test signal among the received relay test data shown in FIG. 6B to the terminal T2. (S809). Thereby, the operation check of the interconnection protection relay 54 can be executed. If it is not in the test mode (N in S808), the relay test cannot be performed, so the process in S809 is skipped.

  Then, the slave station 9 transmits the result of the relay test to the master station 3 and stores it as the processing result 94A3 in the storage unit 94 (S810). At that time, among the received relay test data shown in FIG. 6B, a test response is set according to the test result. Specifically, when a trip signal is received within a predetermined time (for example, 1 second) from the interconnection protection relay 54 via the terminal T4 with respect to the test signal, a result value of “01h” or more is set. On the other hand, “00h” is set when the trip signal is not received within a predetermined time (for example, 1 second) with respect to the test signal or when the test signal is not output because the test mode is not set. Then, relay test data is transmitted to the master station 3 by the communication unit 91. Thereafter, the process returns to S801 to wait for reception of new data.

  When the data type indicates switching to the normal mode (normal switching in S802), the slave station 9 determines whether or not the relay connection mode 94A2 of the storage unit 94 is in the normal mode (S811). If not in the normal mode (N in S811), in order to switch to the normal mode, the signal input / output unit 92 outputs a test switch switching signal to the magnet switch MGS2 (S812). If the switching of the test switches SW1 and SW2 is normally performed as judged from the contact information (Y in S813), the normal mode is set to the relay connection mode 94A2 of the storage unit 94 (S814).

  If the relay connection mode 94A2 is the normal mode in S811 (Y in S811), there is no need to switch the test switch, so the slave station 9 skips the processes in S812 to S814. If the test switch is not switched normally in S813 (N in S813), the process in S814 is skipped.

  Then, the slave station 9 transmits the switching result of the test switch to the master station 3, and stores it as the processing result 94A3 in the storage unit 94 (S815). At that time, among the received test switch switching data shown in FIG. 6A, a control response result is set according to the switching result. More specifically, “FFh” is set when the normal mode has been set or when the switching is normal. On the other hand, if the switching is not normal, “0Fh” is set. Then, the communication switch 91 transmits test switch switching data to the master station 3. Thereafter, the process returns to S801 to wait for reception of new data.

  When the data type is a request for disconnection of the distributed power source 6 (disconnection request in S802), the slave station 9 outputs a transfer cutoff signal to the magnet switch MGS1 by the signal input / output unit 92 (S816). ). Then, the data of the disconnection result corresponding to the open / close state of the switch 52 based on the contact information is transmitted to the master station 3 and stored in the storage unit 94 as the processing result 94A3 (S817). That is, if the switch 52 is open, the disconnection result is “normal”, and if the switch 52 is closed, the disconnection result is “abnormal”. Thereafter, in order to switch to the normal mode, the processes of S811 to S815 are performed, and the process returns to S801 to wait for reception of new data.

  Although the processing of the master station 3 has been described with reference to FIG. 7 and the processing of the slave station 9 has been described with reference to FIG. 8, the data transmission between the master station 3 and the slave station 9 included in these processing is A relay station 4 is interposed. That is, the relay station 4 receives data instructing processing from the master station 3 and transmits it to the slave station 9, while receiving data indicating the processing result from the slave station 9 and transmits it to the master station 3.

  In the power conditioner 5, even in the relay test mode, the system voltage and the like are monitored, and the interconnection protection relay 54 and the switch 52 operate when a true failure occurs. More specifically, referring to FIG. 3, first, when the inverter control circuit 53 detects an abnormality in the power system, the system abnormality information is transmitted to the interconnection protection relay 54. The interconnection protection relay 54 receives system abnormality information from the inverter control circuit 53 and outputs a trip signal. If the slave station 9 does not output a relay test signal to the terminal T2 but receives a trip signal from the terminal T4, the slave station 9 recognizes that a true failure has occurred and transfers a transfer cutoff signal to the magnet switch MGS1. Is output.

  The slave station 9 may transmit a test switch switching signal to the magnet switch MGS2 instead of outputting the transfer cutoff signal. As a result, the test switches SW1 and SW2 are connected to the terminals T1 and T3 on the normal side, respectively, so that the connection protection relay 54 in the normal mode operates to detect an abnormality in the system data, and the magnet switch A transfer cut-off signal is output to MGS1.

  Separately, the master station 3 detects a system abnormality and transmits a disconnection request of the distributed power source 6 to the slave station 9, so that the slave station 9 outputs a transfer cutoff signal to the magnet switch MGS1. As described above, even if the interconnection protection relay 54 is under test or failure, the switch 52 is opened when an abnormality occurs in the power system, so that the transfer interruption function is effective and the distributed power supply 6 Can be prevented.

  In the above embodiment, the program executed by the processing unit (CPU) is recorded on a computer-readable recording medium in order to make each device in the distributed power transfer cutoff system 1 shown in FIG. 1 function. Then, it is assumed that the distributed power supply transfer cutoff system 1 according to the embodiment of the present invention is realized by causing the computer to read and execute the recorded program. In this case, the program may be provided to the computer via a network such as the Internet, or a semiconductor chip or the like in which the program is written may be incorporated in the computer.

  According to the embodiment of the present invention described above, when operating the interconnection protection relay 54, while reducing the burden on both the installer of the power conditioner 5 and the distributed power source 6, the manager of the power system, The safety of the power system can be ensured.

  Specifically, in FIG. 7 and FIG. 8, before performing the operation test of the interconnection protection relay 54 by the procedure in which the slave station 9 responds to the instruction from the master station 3, as shown in S701, S707, S804, and S812. Since the relay connection is returned to the normal mode after the relay connection is set to the test mode and the operation test is completed, the closed state of the switch 52, that is, the state where the distributed power source 6 is connected to the power system is maintained. However, the operation test can be performed safely.

  Next, as shown in S704 to 706, S809, and S810, an operation test of the interconnection protection relay 54 is performed according to a procedure in which the slave station 9 responds to an instruction from the master station 3, and the test result is immediately sent to the master station 3. Therefore, the system manager can immediately cope with the abnormality of the interconnection protection relay 54.

  Furthermore, even if an abnormality occurs in the power system during the operation test of the interconnection protection relay 54, the switch 52 operates so as to be opened, so that the operation test can be performed safely while maintaining the transfer cutoff function. be able to.

  According to the above, the following effects are produced by automating the inspection of the interconnection protection relay 54. First, the burden of time and expense is reduced for both the customer and the system administrator. Next, there is no need for a worker to go to the site, and human errors such as erroneous entry of inspection history, missed communication, and reporting errors do not occur. Then, the system manager can grasp the failure of the interconnection protection relay 54 in real time and can ensure the safety of the power system by responding quickly.

<< Other embodiments >>
As mentioned above, although the form for implementing this invention was demonstrated, the said embodiment is for making an understanding of this invention easy, and is not for limiting and interpreting this invention. The present invention can be changed and improved without departing from the gist thereof, and equivalents thereof are also included in the present invention. For example, the following embodiments can be considered.

(1) In the above embodiment, the slave station 9 performs a series of diagnostic processing (switching to the test mode, connection protection relay 54 to the connection protection relay 54 shown in FIG. In the above description, the test signal is output to the normal mode and the mode is switched to the normal mode. However, the diagnosis process may be performed by another trigger. As an example, the slave station 9 includes an input unit such as a keyboard and a touch panel. Then, it is conceivable that a diagnosis schedule is acquired in advance from the input unit by the operation of the customer, stored in the storage unit 94, and the diagnosis process is performed according to the diagnosis schedule. According to this, since the slave station 9 automatically performs diagnosis according to the once set diagnosis schedule, it is possible to reduce the burden on the customer, the system administrator, and the local workers without relying on human hands. Further, the diagnosis schedule can be adjusted according to each person's intention, the situation of the interconnection protection relay 54, and the like.

  Further, when the local worker goes around the customer's home where the power conditioner 5 and the distributed power source 6 are installed, the diagnosis instruction of the interconnection protection relay 54 is input by operating the input unit, and the slave station 9 It is conceivable to perform a diagnostic process according to the instruction. According to this, the local worker can diagnose the interconnection protection relay 54 at an arbitrary timing.

(2) In the above embodiment, the slave station 9 switches the relay connection mode according to the instruction from the master station 3. However, when the slave station 9 receives the relay test instruction from the master station 3, the slave station 9 A series of processes of “switching, relay test, switching to normal mode” may be performed.

(3) When determining the test input value of the relay test data, the set value of the interconnection protection relay 54 may be acquired and set based on the set value.

3 Master station (device of power system manager)
5 Power conditioner 52 Switch 54 Link protection relay (protective relay)
6 Distributed power supply 9 Slave station (Protective relay diagnostic device)
SW1, SW2 Test switch (switching means)

Claims (5)

Protection that outputs a cut-off signal instructing opening of a switch connected between the power system and the distributed power supply when it is determined that the power system or the distributed power supply connected to the power system is abnormal A protective relay diagnostic device for diagnosing a relay,
Switching means for switching the first connection state in which the protective relay is connected to the measuring instrument of the power system and the switch, or the second connection state in which the protective relay is connected to the protective relay diagnostic device. When,
When the switching means switches to the second connection state, an abnormal value related to the power system is artificially output to the protection relay, and then the protection signal is acquired from the protection relay when the protection signal is acquired. A diagnostic means for determining that the protective relay is abnormal when determining that the relay is normal and not obtaining the interruption signal from the protective relay;
When the diagnostic relay determines that the protective relay is abnormal, an administrator notification means for notifying the device of the power system administrator to that effect;
A return means for switching to the first connection state by the switching means after completing the diagnosis of the protective relay by the diagnostic means;
A protective relay diagnostic apparatus comprising: The protective relay diagnostic device according to claim 1,
Separately from the protective relay, a system abnormality judging means for judging whether or not the power system is abnormal,
While the protective relay is switched to the second connection state, when the power system is determined to be abnormal by the system abnormality determination unit, an abnormality return unit that switches to the first connection state by the switching unit;
A protective relay diagnostic apparatus, further comprising: The protective relay diagnostic device according to claim 1 or claim 2,
The protection relay diagnosis device, wherein the protection relay is diagnosed when an instruction for diagnosis of the protection relay is obtained from a device of an administrator of the power system. The protective relay diagnostic device according to claim 1 or claim 2,
A protection relay diagnosis apparatus, wherein a diagnosis schedule of the protection relay is stored, and the protection relay is diagnosed according to the schedule. The protective relay diagnostic device according to claim 1 or claim 2,
The protective relay diagnosis device, wherein the protective relay is diagnosed when an instruction to diagnose the protective relay is obtained by an operation of a local worker.

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