JP2009290918A - Distributed power system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that, when a conventional distributed power system is installed in an area where failures such as an output overcurrent, an input overvoltage and an input short voltage or the like of an inverter frequently occur due to an instantaneous voltage drop, an instantaneous power failure or a load fluctuation or the like in a commercial power system, the frequency of abnormal stop is limited, thereby frequently causing serious stops of the device and warnings. <P>SOLUTION: The distributed power system comprises a failure information storage means 108 for storing a type of failure and a characteristic value whenever a failure is detected, a failure occurrence pattern storing means 109 for storing, in advance, the type of the failure and the time-series occurrence pattern of the characteristic value, and a failure determining means 110. The failure determining means 110 compares the information stored in the failure information storage means 108 with the information stored in the failure occurrence pattern storing means 109. When the time-series occurrence pattern coincides with the information stored in the failure information storage means 108, the distributed power system is determined as faulty. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a distributed power supply device that supplies AC power to a home load in linkage with a commercial power system.

  Conventionally, this type of distributed power supply device is, for example, as shown in FIG.

  Here, FIG. 7 shows a block diagram of a conventional distributed power supply apparatus, where 1 is a commercial power system, 2 is a load connected to the commercial power system 1 and an inverter described later, 3 is a solar cell as a DC power source, and 4 is An inverter having an input terminal connected to the solar cell 3 and an output terminal connected to the load 2 via the output current detector 5, the low-pass filter 6, the normally closed disconnection switch 7, and the interconnection transformer 8. is there.

Reference numeral 9 denotes a system control circuit that detects a system voltage, a system voltage frequency, and an inverter output current in a state where the inverter 4 is connected to the commercial power system 1, and performs output power control, and 12 includes two BPFs (bands). (Pass filter) 10 and 11 are bimodal band filters, 13 and 14 are AC voltage detectors, and 15 is a smoothing capacitor. (For example, see Patent Document 1)
In the distributed power supply configured as described above, the system control circuit 9 determines the abnormality of the apparatus by monitoring the output frequency of the inverter 4 and the operation status, and if the abnormality of the apparatus is determined to occur, In addition to determining the contents, it is determined whether the number of occurrences of each abnormal content has reached a preset number of times set individually. If the determination is affirmative, the main switch (not shown) of the device is turned off to stop the device in earnest, output an alarm, and display the abnormal stop content on the display device (not shown).
JP-A-8-126338

  However, in the conventional configuration, a distributed power supply device is installed in an area where abnormalities such as output overcurrent, input overvoltage, and input undervoltage of the inverter frequently occur due to instantaneous voltage drop, instantaneous power failure, load fluctuation, etc. In such a case, there is a problem that the full-scale stoppage of the apparatus and a warning frequently occur by limiting the number of abnormal stops.

  The present invention solves the above-mentioned conventional problems, and even when a distributed power supply apparatus is installed in an area where anomalies frequently occur due to instantaneous voltage drop, instantaneous power failure, load fluctuation, etc. of the commercial power system, It is an object of the present invention to provide a distributed power supply device that can determine whether a device has failed without being affected by an abnormality or load fluctuation and can be stopped only when the device has failed.

  In order to solve the above-described conventional problems, a distributed power supply apparatus according to the present invention generates power itself, and in a distributed power supply apparatus linked to a commercial power system, a characteristic value detection unit that detects a plurality of characteristic values; An abnormality detection means for detecting an abnormality based on the characteristic value detected by the characteristic value detection means and determining an abnormality type; an abnormality type when the abnormality detection means detects an abnormality; and the characteristic value detection means An abnormality information storage means for storing characteristic values to be detected; an abnormality generation pattern for storing an abnormality type detected by the abnormality detection means when a failure occurs in advance and a time-series generation pattern of characteristic values detected by the characteristic value detection means Storage means and failure determination means for determining failure of the distributed power supply device, wherein the failure determination means is the abnormality type and characteristics stored in the abnormality information storage means and the abnormality occurrence pattern storage means When time-series generated patterns are matched, and is intended to determine malfunction.

  As a result, even when a distributed power supply system is installed in an area where abnormalities occur frequently due to instantaneous voltage drops, instantaneous power outages or load fluctuations in the commercial power system, the system is not affected by abnormalities in the commercial power system or load fluctuations. Can be stopped only when the device fails.

  Even if a distributed power supply is installed in an area where anomalies frequently occur due to instantaneous voltage drops, instantaneous power outages or load fluctuations in the commercial power system, the distributed power supply apparatus of the present invention can A device failure can be determined without being affected, and can be stopped only when the device fails.

  The first invention is based on the characteristic value detected by the characteristic value detecting means and the characteristic value detecting means for detecting a plurality of characteristic values in the distributed power supply device that generates power and is connected to the commercial power system. An abnormality detection unit that detects an abnormality and determines an abnormality type, an abnormality information storage unit that stores an abnormality type and a characteristic value detected by the characteristic value detection unit when the abnormality detection unit detects an abnormality, and a failure in advance An abnormality occurrence pattern storage means for storing an abnormality type detected by the abnormality detection means and a time-series occurrence pattern of the characteristic value detected by the characteristic value detection means, and a failure determination means for determining a failure of the distributed power supply device The failure determination means determines that a failure occurs when the abnormality type stored in the abnormality information storage means and the abnormality occurrence pattern storage means match the time-series occurrence pattern of the characteristic value.

  With this configuration, even if a distributed power supply is installed in an area where abnormalities occur frequently due to instantaneous voltage drops, instantaneous power outages or load fluctuations in the commercial power system, it is not affected by abnormalities in the commercial power system or load fluctuations. A device failure can be determined and stopped only if the device fails.

  In the second invention, particularly in the distributed power supply device of the first invention, the abnormality information storage means selects and stores the characteristic value detected by the characteristic value detection means in accordance with the abnormality type detected by the abnormality detection means. Therefore, the amount of stored information can be reduced, and the cost can be reduced by using a storage means having a smaller storage capacity, or the determination time for failure determination can be reduced.

  According to a third aspect of the present invention, in the distributed power supply of the first or second aspect of the invention, there is provided a failure location specifying means for specifying a failure location, and when the failure location identification means determines that a failure has occurred, The failure location is specified based on the abnormality type and characteristic value stored in the information storage means, and maintenance personnel can efficiently perform maintenance and repair by obtaining information on the specified failure location. Can do.

  According to a fourth aspect of the present invention, in particular, in the distributed power supply device according to any one of the first to third aspects, the setting unit includes a setting unit, and the setting unit updates the information stored in the abnormality occurrence pattern storage unit or the abnormality information storage unit. Deletes the information stored therein, and can make a failure determination according to the status of the commercial power system and the distributed power supply.

  According to a fifth aspect of the present invention, in particular, in the distributed power supply device according to any one of the first to fourth aspects, the abnormality generation pattern generation unit includes an abnormality type stored in the abnormality information storage unit. Based on the characteristic value, the abnormality type detected by the abnormality detecting unit when a failure occurs and the time series occurrence pattern of the characteristic value detected by the characteristic value detecting unit are generated, and the information stored in the abnormality generating pattern storage unit is stored. Therefore, it is possible to make a failure determination according to the state of the commercial power system in which the distributed power supply apparatus is installed without bothering a person such as a maintenance man.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to this embodiment.
(Embodiment 1)
FIG. 1 shows a block diagram of a distributed power supply apparatus according to Embodiment 1 of the present invention. FIG. 2 shows an abnormality occurrence pattern stored in the abnormality occurrence pattern storage means in the embodiment. FIG. 3 is a flowchart showing a flow of failure determination of the distributed power supply apparatus according to the embodiment.

  In FIG. 1, 101 is a commercial power system that is a single-phase three-wire AC power source composed of a U phase, an O phase, and a W phase, 102 is a household load that consumes AC power supplied from the commercial power system 101, and 103 is This is a distributed power supply device that is connected to a commercial power system and supplies power to the home load 102.

  The distributed power supply device 103 converts the direct current generated by the fuel cell 104 by the fuel cell 104 that generates direct current, the DC / DC circuit 105a, and the DC / AC circuit 105b into alternating current, and is commercialized via the interconnection relay 105c. The inverter 105 connected to the power system 101 and the household load 102, the input / output voltage and current of the DC / DC circuit 105a and the DC / AC circuit 105b, the system voltage frequency, the deparallel time of the interconnection relay 105c, A characteristic value detecting means 106 for detecting a characteristic value such as the current time is provided.

  In addition, the distributed power supply device 103 has an overvoltage, an undervoltage, an overcurrent, a system voltage frequency of the input / output of the DC / DC circuit 105a and the DC / AC circuit 105b based on the characteristic value detected by the characteristic value detecting unit 106. The abnormality detection means 107 that detects an abnormality such as an increase or decrease in the operation or the isolated operation and determines the abnormality type, and the abnormality type and characteristic value detection means 106 that are determined when the abnormality detection means 107 detects an abnormality. Abnormal information storage means 108 for storing the characteristic value to be detected is provided.

  In addition, the distributed power supply apparatus 103 stores in advance a time series occurrence pattern of the abnormality type detected by the abnormality detection means 107 and the characteristic value detected by the characteristic value detection means 106 when the distributed power supply apparatus 103 fails. An abnormality occurrence pattern storage unit 109; a failure determination unit 110 that determines a failure of the distributed power supply device 103 when the abnormality detection unit 107 detects an abnormality; an LCD 111 that displays a warning when the failure determination unit 110 determines a failure; An external memory 112a for storing update information to the abnormality occurrence pattern storage unit 109 is provided.

  Further, the distributed power supply apparatus 103 includes a setting unit 112 configured by a switch 112b for operating information stored in the external memory 112a to reflect the abnormality occurrence pattern storage unit 109 and erasing information stored in the abnormality information storage unit 108. Prepare.

  With respect to the distributed power supply apparatus configured as described above, the operation and action will be described below with reference to FIGS.

  First, failure determination of the distributed power supply device 103 will be described.

  The distributed power supply device 103 detects the characteristic value by the characteristic value detecting unit 106, and based on the detected characteristic value, the abnormality detecting unit 107 detects the input / output voltages of the DC / DC circuit 105a and the DC / AC circuit 105b. It is determined whether there is an abnormality or not by determining whether the level of current, system voltage frequency, etc., the rate of change, or the amount of change is greater than or less than a predetermined value and whether or not it is in a single operation state (STEP 201, 202). .

  If the determination result is abnormal, the apparatus is stopped, the abnormality detection unit 107 determines the abnormality type, and the determined abnormality type and characteristic value are stored in the abnormality information storage unit 108 (STEPs 203 to 206).

  Here, the determination of the abnormality type by the abnormality detection unit 107 is, for example, when the instantaneous output current of the DC / AC circuit 105b is 15 A or more, the abnormality type is determined as a DC / AC circuit output overcurrent.

  After storing the characteristic value and the abnormality type, the failure determination unit 110 compares the characteristic value stored in the abnormality information storage unit 108 and the abnormality occurrence pattern storage unit 109 with the time series occurrence pattern of the abnormality type, It is determined whether or not the distributed power supply device 103 has failed (STEP 207).

  In the failure determination in the present embodiment, the failure type and the characteristic value stored in the abnormality information storage means 108 are determined as a device failure when the pattern satisfying the abnormality type and characteristic value in FIG. judge.

  Thus, for example, when an instantaneous voltage drop or an instantaneous power failure of the commercial power system 101 occurs while the interconnection relay 105c is in parallel, an abnormality such as an output overcurrent of the DC / AC circuit 105b may be detected. Since the probability of occurrence within 3 s of parallel times within 10 s, such as NO2 of 2, is extremely small, the distributed power supply device 103 is erroneously determined to be faulty due to the instantaneous voltage drop of the commercial power system 101 and the occurrence of an instantaneous power failure. There is nothing.

  On the other hand, when the DC / AC circuit 105b fails, an abnormality called the output overcurrent of the DC / AC circuit 105b is detected immediately after the interconnection relay 105c is connected in parallel. Therefore, an abnormality that satisfies the generation pattern of NO1 in FIG. 2 occurs. The failure of the device can be determined.

  After determining the device failure, if it is determined that there is no failure, restart is performed (STEP 208, 209). On the other hand, if it is determined that there is a failure, a warning is displayed on the LCD 111 to notify that the device has failed, and a full-scale stop is performed so that it cannot be restarted unless operated by a maintenance man or the like (STEP 210).

  Next, a maintenance method using the setting means 112 by a maintenance man will be described.

  When a failure occurs in the distributed power supply device 103, the maintenance man erases the information stored in the abnormality information storage unit 108 by using the switch 112b after repairing the corresponding failure portion. As a result, when the operation of the apparatus is started again, the failure determination unit 110 determines that there is no failure of the apparatus, so that the apparatus can be restarted.

  In addition, when updating the storage information of the abnormality occurrence pattern storage means 109 by a maintenance man or the like, the information created in advance is stored in the external memory 112a, and the storage information in the external memory 112a is generated by operating the switch 112b. Update to the pattern storage means 109.

  For example, the DC / AC circuit output overcurrent is frequently abnormal at 7 to 8 o'clock due to an instantaneous voltage drop or an instantaneous power failure of the commercial power system 101, a large fluctuation in the home load 102, or the like, not a failure of the distributed power supply device 103. When the type is detected, the information of NO1 in FIG. 2 is updated to information that “occurs within 10 s after three consecutive reconnections excluding 7 to 8 o'clock”.

  In this embodiment, the occurrence pattern stored in the abnormality occurrence pattern storage unit 109 is as shown in FIG. 2, but when a specific timing can be recognized from the characteristic value detected by the characteristic value detection unit 106. Failure determination may be performed based on the occurrence pattern excluding the situation.

  Further, in the present embodiment, the pattern shown in FIG. 2 is used as the generation pattern stored in the abnormality generation pattern storage unit 109. However, the input / output overvoltage and undervoltage of the DC / DC circuit 105a and DC / AC circuit 105b are used. The failure determination may be performed by providing a similar generation pattern for overcurrent, system voltage frequency increase / decrease, isolated operation state detection, and the like.

  As described above, in the present embodiment, the failure determination unit 110 detects that the abnormality type stored in the abnormality information storage unit 108 and the abnormality occurrence pattern storage unit 109 matches the time-series occurrence pattern of the characteristic value. In order to determine a failure, even if the distributed power supply 103 is installed in an area where the abnormality frequently occurs due to an instantaneous voltage drop of the commercial power system 101, an instantaneous power failure, a fluctuation in the household load 102, or the like, A device failure can be determined without being affected by abnormalities or fluctuations in the household load 102, and can be stopped only when the device has failed.

In the present embodiment, the setting means 112 updates the information stored in the abnormality occurrence pattern storage means 109 or deletes the information stored in the abnormality information storage means 108, so that the commercial power system 101 and the distributed power supply A failure determination according to the status of the device 103 can be performed.
(Embodiment 2)
FIG. 4 shows a block diagram of a distributed power supply apparatus according to Embodiment 2 of the present invention. In addition to the configuration of FIG. 1, the distributed power supply device 103 generates time-sequential generation of abnormality types and characteristic values when the device fails based on the abnormality types and characteristic values stored in the abnormality information storage unit 108. A failure comprising an abnormality occurrence pattern generation means 113 for generating a pattern, a failure information storage unit 114a for storing an abnormality type and a characteristic value generated at the time of each failure, and a failure location specifying unit 114b for specifying the failure location The location specifying means 114 is provided.

  FIG. 5 shows failure location specifying information stored by the failure location specifying means in the embodiment. FIG. 6 is a flowchart showing a flow of failure determination of the distributed power supply apparatus according to the embodiment.

  The operation and action of the distributed power supply device configured as described above will be described below with reference to FIGS. 2 and 4 to 6.

  Since the process from the detection of the characteristic value by the characteristic value detection unit 106 to the determination of the abnormality type by the abnormality detection unit 107 is the same as that of the first embodiment, the description is omitted (STEPs 301 to 305).

  After the abnormality type is determined by the abnormality detection unit 107, the characteristic value detected by the characteristic value detection unit 106 is selected based on the determined abnormality type, and the abnormality type and the selected characteristic value are stored in the abnormality information storage unit 108. (STEP 306, 307).

  Here, the selection and storage of the characteristic value is performed when, for example, the abnormality type is a type related to the output side of the DC / AC circuit 105b such as an output overcurrent or output overvoltage of the DC / AC circuit 105b. Characteristic values such as the output voltage and current and the parallel time of the interconnection relay 105c are selected and stored.

  After storing the abnormality type and characteristic value, the abnormality occurrence pattern generation unit 113 generates a time-series generation pattern of the abnormality type and characteristic value based on the abnormality type and characteristic value stored in the abnormality information storage unit 108. Then, it is stored in the abnormality occurrence pattern storage means 109 (STEP 308).

  Here, the generation of the occurrence pattern is, for example, on the third day of the seventh day, if an abnormal type of DC / AC circuit output overcurrent is stored at 7 to 8 o'clock, 7 to 8 o'clock is caused by a factor outside the failure of the device. It is determined that an abnormality is detected, and a new generation pattern of “occurrence within 10 s after three consecutive reconnections except for 7-8 o'clock” is generated as the condition of NO1 in FIG. The data is stored in the abnormality occurrence pattern storage unit 109.

  After the generation pattern is generated, the failure determination unit 110 compares the time series generation patterns stored in the abnormality information storage unit 108 and the abnormality generation pattern storage unit 109 to determine whether the distributed power supply device 103 has failed. It is determined whether or not (STEP309).

  In the failure determination in the present embodiment, the failure type and the characteristic value stored in the abnormality information storage means 108 are determined as a device failure when the pattern satisfying the abnormality type and characteristic value in FIG. judge. However, characteristic values that are not stored in the abnormality information storage unit 108 are excluded from determination targets.

  After determining the failure of the apparatus, if it is determined that there is no failure, restart is performed (STEP 310, 311). On the other hand, when it is determined that there is a failure, the failure location is determined by comparing the abnormality information storage means 108 and the failure information storage portion 114a by the failure location specifying unit 114b (STEP 312).

  For example, when the abnormality type and characteristic value stored at the end of the abnormality information storage unit 108 matches the failure location identification information of NO2 in FIG. 5 stored in the failure information storage unit 114a, the DC / AC circuit 105b fails. Is determined.

  After identifying the failure location of the device, a warning display of the device failure and a display of the failure location are displayed on the LCD 111, and a full-scale stop that can only be started by an operation by a maintenance man or the like is performed (STEP 313).

  As described above, in the present embodiment, the abnormality information storage unit 108 selects and stores the characteristic value detected by the characteristic value detection unit 106 according to the abnormality type detected by the abnormality detection unit 107. The amount can be reduced, and the cost can be reduced by using storage means having a smaller storage capacity, or the determination time for failure determination can be reduced.

  Further, in the present embodiment, the failure location specifying means 114 specifies the failure location based on the abnormality type and the characteristic value stored in the abnormality information storage means 108 when the failure determination means 110 determines a failure. Therefore, the maintenance man can efficiently perform maintenance, repair, etc. by obtaining information on the specified failure location.

  Further, in the present embodiment, the abnormality occurrence pattern generation unit 113 detects the abnormality type and characteristic value detected by the abnormality detection unit 107 when a failure occurs based on the abnormality type and characteristic value stored in the abnormality information storage unit 108. Since the time series generation pattern of the characteristic value detected by the detection unit 106 is generated and the information stored in the abnormality generation pattern storage unit 109 is updated, the distributed power supply apparatus 103 is not required without the need for maintenance personnel or the like. Can be determined according to the situation of the commercial power system 101 in which is installed.

  As described above, the distributed power supply according to the present invention can be applied to the commercial power system even when the distributed power supply is installed in an area where anomalies frequently occur due to instantaneous voltage drop, instantaneous power failure, load fluctuation, etc. It is possible to determine the failure of a device without being affected by abnormalities and load fluctuations and stop only when the device breaks down, such as a fuel cell device, solar power generation device, wind power generation device, solar thermal power generation device The present invention can also be applied to uses such as a distributed power supply device.

Block diagram of distributed power supply apparatus according to Embodiment 1 of the present invention Explanatory drawing which shows the abnormality occurrence pattern which the abnormality occurrence pattern memory | storage means in Embodiment 1 memorize | stores The flowchart which shows the flow of the failure determination of the distributed power supply device in Embodiment 1 Block diagram of a distributed power supply apparatus according to Embodiment 2 of the present invention Explanatory drawing which shows the fault location specific information which the fault location specific means in Embodiment 2 memorize | stores The flowchart which shows the flow of the failure determination of the distributed power supply device in Embodiment 2 Block diagram of a conventional distributed power supply

Explanation of symbols

DESCRIPTION OF SYMBOLS 103 Distributed type power supply device 106 Characteristic value detection means 107 Abnormality detection means 108 Abnormality information storage means 109 Abnormality occurrence pattern storage means 110 Failure determination means 112 Setting means 113 Abnormality occurrence pattern generation means 114 Failure location identification means

Claims (5)

In a distributed power supply that generates its own power and links to a commercial power system,
Characteristic value detecting means for detecting a plurality of characteristic values;
Abnormality detection means for detecting an abnormality based on the characteristic value detected by the characteristic value detection means, and determining an abnormality type;
Abnormality information storage means for storing an abnormality type when the abnormality detection means detects an abnormality and a characteristic value detected by the characteristic value detection means;
An abnormality occurrence pattern storage means for storing an abnormality type detected by the abnormality detection means when a failure occurs in advance and a time-series occurrence pattern of the characteristic value detected by the characteristic value detection means;
Failure determination means for determining failure of the distributed power supply device,
The distributed power supply apparatus, wherein the failure determination means determines that a failure occurs when the abnormality type and characteristic value time-series occurrence patterns stored in the abnormality information storage means and the abnormality occurrence pattern storage means match. The distributed power supply apparatus according to claim 1, wherein the abnormality information storage unit selects and stores a characteristic value detected by the characteristic value detection unit according to an abnormality type detected by the abnormality detection unit. A failure location specifying means for specifying a failure location, wherein the failure location characteristic means is based on an abnormality type and a characteristic value stored in the abnormality information storage means when the failure determination means determines a failure. The distributed power supply device according to claim 1 or 2, wherein a fault location is specified. 4. The apparatus according to claim 1, further comprising a setting unit, wherein the setting unit updates information stored in the abnormality occurrence pattern storage unit or deletes information stored in the abnormality information storage unit. Distributed power supply. An abnormality occurrence pattern generation means, and the abnormality occurrence pattern generation means detects the abnormality type and the characteristic detected by the abnormality detection means when a failure occurs based on the abnormality type and characteristic value stored in the abnormality information storage means. 5. The distributed power supply device according to claim 1, wherein a time-sequential generation pattern of characteristic values detected by the value detection unit is generated, and information stored in the abnormality occurrence pattern storage unit is updated.

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