JP2018098902A - Monitoring system and monitoring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a monitoring system and a monitoring device which can establish a time synchronization between devices at an early stage, in a configuration collecting measurement results concerning a solar cell panel by the respective devices.SOLUTION: A monitoring system has a single or a plurality of monitoring devices performing a measurement concerning a solar cell panel, and a collection device. Each of the monitoring devices transmits a time synchronization request to the collection device, which receives the time synchronization request transmitted from each of the monitoring devices and transmits a time synchronization response including a current time to each of the monitoring devices. Each of the monitoring devices receives the time synchronization response transmitted from the collection device, sets a current time of the self device on the basis of the current time included in the time synchronization response, and transmits the time synchronization request to the collection device at a timing based on identification information of the self device.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a monitoring system and a monitoring apparatus.

  In recent years, techniques for detecting a failure of a photovoltaic power generation system have been developed. For example, JP 2012-205078 A (Patent Document 1) discloses a monitoring system for photovoltaic power generation as follows. That is, the photovoltaic power generation monitoring system is a photovoltaic power generation monitoring system that monitors the power generation status of the solar cell panel for a photovoltaic power generation system that aggregates outputs from a plurality of solar cell panels and sends them to a power converter. A measuring device for measuring the power generation amount of each solar cell panel provided in a place where the output electric circuits from the plurality of solar cell panels are aggregated, and connected to the measurement device, A lower communication device having a function of transmitting measurement data, an upper communication device having a function of receiving the measurement data transmitted from the lower communication device, and the solar cell panel via the upper communication device And a management device having a function of collecting the measurement data for each.

JP 2012-205078 A

  In a photovoltaic power generation monitoring system such as the system described in Patent Document 1, a plurality of measuring devices are provided, and each measuring device measures a solar cell panel corresponding to itself. And if the measurement data of the predetermined period by each measuring device are compared, the failure of a solar cell panel, etc. can be detected. In this case, in order to synchronize the time between a plurality of measuring devices, information on time is transmitted and received between each measuring device and the management device, so that time synchronization processing is performed between each measuring device and the management device. Is done.

  In this time synchronization processing, it is desirable that the time synchronization processing with the management device is completed early in all measurement devices by avoiding interference between signals transmitted from the plurality of measurement devices to the management device.

  This invention was made in order to solve the above-mentioned subject, and the object is to establish the time synchronization between each device early in the composition which collects the measurement result about the solar cell panel by each device. It is to provide a monitoring system and a monitoring device that can be used.

  (1) In order to solve the above-described problem, a monitoring system according to an aspect of the present invention includes one or a plurality of monitoring devices that perform measurement related to a solar battery panel, and a collection device, and each of the monitoring devices includes a time A synchronization request is transmitted to the collection device, the collection device receives the time synchronization request transmitted from each of the monitoring devices, and transmits a time synchronization response including a current time to each of the monitoring devices; The monitoring device receives the time synchronization response transmitted from the collection device, sets its current time based on the current time included in the time synchronization response, and each monitoring device identifies itself The time synchronization request is transmitted to the collection device at a timing based on information.

  (5) In order to solve the above-described problem, a monitoring device according to an aspect of the present invention is a monitoring device that performs measurement related to a solar battery panel, and includes a transmission unit that transmits a time synchronization request, and a time that includes the current time. A receiving unit that receives a synchronization response; and a setting unit that sets a current time in the monitoring device of itself based on the current time included in the time synchronization response received by the receiving unit; Transmits the time synchronization request at a timing based on the identification information of its own monitoring device.

  The present invention can be realized not only as a monitoring system including such a characteristic processing unit, but also as a monitoring method using such characteristic processing as a step, or for causing a computer to execute such a step. Or as a program.

  In addition, the present invention can be realized not only as a monitoring apparatus including such a characteristic processing unit, but also as a monitoring method using such characteristic processing as a step, or causing a computer to execute such a step. Or can be realized as a program. Further, it can be realized as a semiconductor integrated circuit that realizes part or all of the monitoring device.

  ADVANTAGE OF THE INVENTION According to this invention, the time synchronization between each apparatus can be established at an early stage in the structure which collects the measurement result regarding the solar cell panel by each apparatus.

FIG. 1 is a diagram showing a configuration of a photovoltaic power generation system according to an embodiment of the present invention. FIG. 2 is a diagram showing the configuration of the current collecting unit according to the embodiment of the present invention. FIG. 3 is a diagram showing a configuration of the solar cell unit according to the embodiment of the present invention. FIG. 4 is a diagram showing a configuration of the monitoring system according to the embodiment of the present invention. FIG. 5 is a diagram showing the configuration of the monitoring apparatus according to the embodiment of the present invention. FIG. 6 is a diagram showing in detail the configuration of the monitoring apparatus according to the embodiment of the present invention. FIG. 7 is a diagram illustrating a first example of transmission timing of a time synchronization request transmitted from each monitoring apparatus according to the embodiment of the present invention. FIG. 8 is a diagram illustrating a second example of the transmission timing of the time synchronization request transmitted from each monitoring apparatus according to the embodiment of the present invention. FIG. 9 is a diagram for explaining a current time setting method in the monitoring apparatus according to the embodiment of the present invention. FIG. 10 is a diagram illustrating an example of the transmission timing of measurement information from each monitoring apparatus and the retransmission timing of the time synchronization request according to the embodiment of the present invention.

  First, the contents of the embodiment of the present invention will be listed and described.

  (1) A monitoring system according to an embodiment of the present invention includes one or a plurality of monitoring devices that perform measurement related to a solar battery panel and a collection device, and each of the monitoring devices sends a time synchronization request to the collection device. And the collection device receives the time synchronization request transmitted from each of the monitoring devices, and transmits a time synchronization response including the current time to each of the monitoring devices. The time synchronization response transmitted from the time synchronization response is received, the current time of the self is set based on the current time included in the time synchronization response, each monitoring device at the timing based on its own identification information, A time synchronization request is transmitted to the collection device.

  With such a configuration, the time synchronization requests transmitted from the respective monitoring devices can be prevented from interfering with each other and the possibility of reaching the collection device can be increased, so that time synchronization between the monitoring device and the collection device is achieved. The possibility to establish can be increased. As a result, it can be prevented that it takes a long time to establish time synchronization. Therefore, in the configuration for collecting the measurement results related to the solar cell panel by each device, time synchronization between the devices can be established early.

  (2) Preferably, each of the monitoring devices transmits measurement information indicating a result of the measurement to the collection device, a periodic transmission period of the measurement information is set, and a part of the transmission period is set. The transmission of the measurement information from each of the monitoring devices is permitted in the transmittable period that is a period, and the monitoring device can retransmit the time synchronization request. A plurality of retransmission timings are set so as to be included in a transmission prohibition period that is a period other than the transmittable period.

  With such a configuration, there is an opportunity to transmit a time synchronization request that does not interfere with measurement information, so that the possibility of the time synchronization request reaching the collection device can be increased.

  (3) More preferably, each of the monitoring devices periodically resends the time synchronization request.

  With such a configuration, the retransmission timing of the time synchronization request can be easily adjusted by setting the retransmission cycle of the time synchronization request.

  (4) More preferably, the retransmission period is set so that the retransmission timing is included in the transmission prohibition period at least once within a predetermined synchronization period including a plurality of the transmission periods.

  With such a configuration, it is possible to provide an opportunity that the time synchronization request does not interfere with the measurement information with certainty in a plurality of predetermined transmission cycles.

  (5) The monitoring device according to the embodiment of the present invention is a monitoring device that performs measurement related to the solar battery panel, and includes a transmission unit that transmits a time synchronization request and a reception unit that receives a time synchronization response including the current time. And a setting unit that sets a current time in the own monitoring device based on the current time included in the time synchronization response received by the receiving unit, and the transmission unit is the own monitoring device The time synchronization request is transmitted at a timing based on the identification information.

  With such a configuration, the time synchronization requests transmitted from the respective monitoring devices can be prevented from interfering with each other and the possibility of reaching the collection device can be increased, so that time synchronization between the monitoring device and the collection device is achieved. The possibility to establish can be increased. As a result, it can be prevented that it takes a long time to establish time synchronization. Therefore, in the configuration for collecting the measurement results related to the solar cell panel by each device, time synchronization between the devices can be established early.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated. Moreover, you may combine arbitrarily at least one part of embodiment described below.

<Configuration and basic operation>
[Configuration of solar power generation system]
FIG. 1 is a diagram showing a configuration of a photovoltaic power generation system according to an embodiment of the present invention.

  With reference to FIG. 1, the photovoltaic power generation system 401 includes four current collecting units 60 and a PCS 8. The PCS 8 includes a copper bar 7 and a power conversion unit 9.

  In FIG. 1, four current collecting units 60 are representatively shown, but a larger or smaller number of current collecting units 60 may be provided.

  FIG. 2 is a diagram showing the configuration of the current collecting unit according to the embodiment of the present invention. Referring to FIG. 2, current collection unit 60 includes four solar cell units 75 and copper bar 72.

  In FIG. 2, four solar cell units 75 are representatively shown, but a larger or smaller number of solar cell units 75 may be provided.

  FIG. 3 is a diagram showing a configuration of the solar cell unit according to the embodiment of the present invention.

  Referring to FIG. 3, solar cell unit 75 includes three solar cell panels 78 and copper bar 77.

  Although three solar cell panels 78 are representatively shown in FIG. 3, a larger or smaller number of solar cell panels 78 may be provided.

  The solar cell panel 78 is, for example, a string in which a plurality of solar cell panels are connected in series. Note that the solar cell panel 78 is not limited to a configuration including a plurality of solar cell panels, and may include a single solar cell panel.

  In the solar power generation system 401, output lines 1, 5, 2 from the plurality of solar battery panels 78, that is, power lines are electrically connected to the PCS 8, respectively.

  More specifically, output line 1 of solar cell panel 78 has a first end connected to solar cell panel 78 and a second end connected to copper bar 77. Each output line 1 is aggregated to the output line 5 via a copper bar 77. The copper bar 77 is provided, for example, inside a connection box 76 that is an example of a housing.

  When solar panel 78 receives sunlight, it converts the received sunlight energy into DC power, and outputs the converted DC power to output line 1.

  2 and 3, output line 5 has a first end connected to copper bar 77 and a second end connected to copper bar 72 in corresponding solar cell unit 75. Each output line 5 is aggregated into the output line 2 via a copper bar 72. The copper bar 72 is provided, for example, inside a current collection box 71 that is an example of a housing.

  Referring again to FIG. 1, in the photovoltaic power generation system 401, as described above, the output lines 1 from the plurality of solar battery panels 78 are aggregated into the output line 5, and the output lines 5 are aggregated into the output line 2. Each output line 2 is electrically connected to a PCS 8 which is an example of a power converter.

  More specifically, each output line 2 has a first end connected to the copper bar 72 in the corresponding current collecting unit 60 and a second end connected to the copper bar 7. In the PCS 8, the internal line 3 has a first end connected to the copper bar 7 and a second end connected to the power conversion unit 9.

  The PCS 8 is provided, for example, inside the container 6. In the PCS 8, the power conversion unit 9 uses, for example, DC power generated in each solar panel 78 as output line 1, copper bar 77, output line 5, copper bar 72, output line 2, copper bar 7, and internal line 3. When received via, it converts the received DC power into AC power and outputs it to the system.

[Configuration of monitoring system]
FIG. 4 is a diagram showing a configuration of the monitoring system according to the embodiment of the present invention.

  With reference to FIG. 4, the monitoring system 301 includes a plurality of monitoring devices 111, a collection device 101, and a management device 151.

  In FIG. 4, four monitoring devices 111 provided corresponding to one current collection unit 60 are representatively shown, but a larger or smaller number of monitoring devices 111 may be further provided. The monitoring system 301 includes one collection device 101, but may include a plurality of collection devices 101.

  The monitoring system 301 is used for the solar power generation system 401. In the monitoring system 301, sensor information in the monitoring device 111 that is a child device is transmitted to the collection device 101 that is a parent device regularly or irregularly.

  The monitoring device 111 is provided in the current collection unit 60, for example. More specifically, four monitoring devices 111 are provided corresponding to the four solar cell units 75, respectively. Each monitoring device 111 is electrically connected to the corresponding output line 5, for example.

  The monitoring device 111 measures the current of each output line 1 in the corresponding solar cell unit 75 with a sensor. Moreover, the monitoring apparatus 111 measures the voltage of the output line 5 in the corresponding solar cell unit 75 with a sensor.

  The collection device 101 is provided in the vicinity of the PCS 8, for example. More specifically, for example, the collection device 101 is provided in correspondence with the PCS 8 inside the container 6 and is electrically connected to the copper bar 7 via the signal line 46. Note that the collection device 101 may be provided outside the container 6.

  The monitoring device 111 and the collection device 101 perform transmission and reception of information by performing power line communication (PLC: Power Line Communication) via the output lines 2 and 5.

  More specifically, each monitoring device 111 calls the current and voltage measurement results of the corresponding output line, and communication identification information (hereinafter referred to as “communication ID (Identification)”) as identification information for its own communication. .) To the collection apparatus 101. For example, the collection device 101 collects a set of measurement results and communication IDs notified from each monitoring device 111 and notifies the management device 151 of a plurality of sets of collected measurement results and communication IDs.

  For example, the management device 151 detects a failure of the solar cell unit 75 corresponding to each monitoring device 111 by comparing the measurement results of the monitoring devices 111 for a predetermined period. For this reason, it is necessary to synchronize the time between the plurality of monitoring apparatuses 111. For example, the time synchronization between the monitoring apparatuses 111 is performed based on the time of the collection apparatus 101.

  More specifically, for example, when the monitoring device 111 is activated by receiving power supplied from the solar battery panel 78, the monitoring device 111 transmits a time synchronization request Rq for receiving a notification of the current time in the collection device 101 to the collection device 101.

  The collection device 101 receives the time synchronization request Rq transmitted from the monitoring device 111, and acquires the current time by confirming the count value of its own counter, for example. Then, the collection device 101 transmits a time synchronization response Rs including the acquired current time to the monitoring device 111 that is a transmission source of the time synchronization request Rq.

  The monitoring device 111 receives the time synchronization response Rs transmitted from the collection device 101, and sets the count value of its own counter indicating the current time, for example, based on the current time included in the time synchronization response Rs. When each monitoring device 111 sets such a current time, the time between the plurality of monitoring devices 111 is synchronized.

[Monitoring device]
(Overview)
FIG. 5 is a diagram showing the configuration of the monitoring apparatus according to the embodiment of the present invention. In FIG. 5, the output line 1, the output line 5, the copper bar 77 and the copper bar 72 are shown in more detail.

  Referring to FIG. 5, output line 1 includes a positive output line 1p and a negative output line 1n. The output line 5 includes a plus side output line 5p and a minus side output line 5n.

  The copper bar 77 includes a plus side copper bar 77p and a minus side copper bar 77n. The copper bar 72 includes a plus-side copper bar 72p and a minus-side copper bar 72n corresponding to the plus-side output line 5p and the minus-side output line 5n, respectively.

  The plus side output line 1p has a first end connected to the corresponding solar cell panel 78 and a second end connected to the plus side copper bar 77p. Negative side output line 1n has a first end connected to the corresponding solar cell panel 78 and a second end connected to negative side copper bar 77n.

  The plus side output line 5p has a first end connected to the plus side copper bar 77p and a second end connected to the plus side copper bar 72p in the current collection box 71. The negative output line 5n has a first end connected to the negative copper bar 77n and a second end connected to the negative copper bar 72n in the current collection box 71.

  The monitoring device 111 includes a detection unit 11, three current sensors 16, a voltage sensor 17, and a communication unit (reception unit and transmission unit) 14. Note that the monitoring device 111 may further include a large number or a small number of current sensors 16 depending on the number of output lines 1.

  For example, the monitoring device 111 is provided in the vicinity of the solar cell panel 78. Specifically, the monitoring device 111 is accommodated, for example, in a connection box 76 provided with a copper bar 77 to which the output line 1 to be measured is connected. Note that the monitoring device 111 may be provided outside the connection box 76.

  The monitoring device 111 is electrically connected to, for example, the plus side output line 5p and the minus side output line 5n via the plus side power line 26p and the minus side power line 26n, respectively.

(Send time synchronization request)
FIG. 6 is a diagram showing in detail the configuration of the monitoring apparatus according to the embodiment of the present invention.

  Referring to FIG. 6, in addition to detection unit 11, three current sensors 16, voltage sensor 17, and communication unit 14, monitoring device 111 further includes a processing unit (setting unit) 12, a counter 13, and a storage unit. 15 and a DC / DC converter 19.

  Each circuit in the monitoring device 111 operates using the output voltage of the solar battery panel 78 supplied from the output line 5 as a power supply voltage.

  More specifically, DC / DC converter 19 boosts or reduces the DC voltage of solar cell panel 78 received from negative output line 5n and positive output line 5p via negative power supply line 26n and positive power supply line 26p, respectively. The voltage is stepped down to generate a DC voltage Vc. Then, the DC / DC converter 19 outputs the generated DC voltage Vc to each circuit in the monitoring device 111.

  The communication unit 14 transmits and receives information by power line communication via the output line 5 and the power line 26.

  The counter 13 counts clock pulses generated by, for example, an oscillation circuit using a crystal resonator and holds the count value. As described above, this count value indicates the current time in its own monitoring device 111, for example.

  In the storage unit 15, for example, the communication ID of the own monitoring device 111 is stored. The communication ID of the monitoring device 111 is an ID input in advance to the monitoring device 111 by the administrator or an ID notified in advance to the monitoring device 111 by the collection device 101.

  The communication ID includes, for example, a network ID and a node ID. A plurality of monitoring apparatuses 111 whose collection destinations 101 have the same transmission destination of the measurement information Me indicating the measurement result of the sensor are each assigned a common network ID to the collection apparatus 101 and different node IDs. Is done.

  For example, when the solar cell panel 78 starts power generation and each monitoring device 111 is activated, the processing unit 12 uses the node ID stored in the storage unit 15 to synchronize the time from the activation timing of the own monitoring device 111. A waiting time T until the transmission timing of the request Rq is calculated.

  Then, the processing unit 12 monitors the count value of the counter 13 and outputs a time synchronization request Rq to the communication unit 14 at a timing when the standby time T has elapsed from the activation timing. The communication unit 14 transmits the time synchronization request Rq received from the processing unit 12 to the collection device 101 via the power supply line 26, the output lines 5, 2, and the signal line 46.

(A) Specific example 1
FIG. 7 is a diagram illustrating a first example of transmission timing of a time synchronization request transmitted from each monitoring apparatus according to the embodiment of the present invention.

  Here, for example, in addition to the communication ID, the storage unit 15 further stores a maximum value Tm of the standby time T and a maximum number n of the monitoring devices 111 that can be arranged in the monitoring system 301. Further, as illustrated in FIG. 7, it is assumed that the node IDs of the monitoring devices 111 in the monitoring system 301 are “1” to “n”.

  The processing unit 12 in each monitoring device 111 uses, for example, the node ID stored in the storage unit 15 in the own monitoring device 111, the maximum value Tm of the standby time T, and the maximum number n of the monitoring devices 111. The waiting time T is calculated so that the transmission timing of the time synchronization request Rq in the monitoring device 111 is shifted by Tm / n.

  For example, the waiting time T calculated by the processing unit 12 in the monitoring device 111 (ID1) whose node ID is “1” is T1, and the processing unit 12 in the monitoring device 111 (ID2) whose node ID is “2”. Is the waiting time T calculated by the processing unit 12 in the monitoring device 111 (IDn) whose node ID is “n”.

  In this case, for example, standby time T1 = Tm / n, standby time T2 = (Tm / n) × 2, and standby time Tn = (Tm / n) × n = Tm.

  When each monitoring device 111 is activated at time t0, the monitoring device 111 (ID1) transmits a time synchronization request Rq to the collection device 101 at a timing when the standby time T1 has elapsed from time t0. In addition, the monitoring device 111 (ID2) transmits a time synchronization request Rq to the collection device 101 at a timing when the standby time T2 has elapsed from the time t0. In addition, the monitoring device 111 (IDn) transmits a time synchronization request Rq to the collection device 101 at a timing when the standby time Tn has elapsed from time t0.

  The collection device 101 receives the time synchronization request Rq transmitted from the monitoring device 111, and transmits a time synchronization response Rs including the current time to the monitoring device 111 that is the transmission source of the time synchronization request Rq.

(B) Specific example 2
FIG. 8 is a diagram illustrating a second example of the transmission timing of the time synchronization request transmitted from each monitoring apparatus according to the embodiment of the present invention. In FIG. 8, the transmission timing of the time synchronization response Rs from the collection device 101 is not shown.

  Here, it is assumed that the number of monitoring devices 111 included in the monitoring system 301 is k (<n), which is smaller than the maximum number n, and the node IDs of the monitoring devices 111 are “1” to “k”.

  The processing unit 12 in each monitoring device 111 uses, for example, the node ID stored in the storage unit 15 in the own monitoring device 111, the maximum value Tm of the standby time T, and the maximum number n of the monitoring devices 111. The standby time T is calculated so that the transmission timing of the time synchronization request Rq in the monitoring device 111 is shifted by (Tm / n) × 2.

  More specifically, the processing unit 12 in each monitoring device 111 has a standby time Tx = (Tm) when the node ID “x” (x is an integer not less than 1 and not more than k) of the own monitoring device 111 is an even number. / N) × x is calculated.

  Further, for example, when the node ID “x” of the own monitoring device 111 is an odd number, the processing unit 12 in each monitoring device 111 calculates the standby time Tx = Tm− (Tm / n) × x.

  That is, with reference to FIG. 8, the standby time T1 calculated by the processing unit 12 in the monitoring device 111 (ID1) with the node ID “1” is T1 = Tm− (Tm / n). The standby time T2 calculated by the processing unit 12 in the monitoring device 111 (ID2) with the node ID “2” is T2 = (Tm / n) × 2.

  The standby time T3 calculated by the processing unit 12 in the monitoring device 111 (ID3) with the node ID “3” is T3 = Tm− (Tm / n) × 3. The standby time T4 calculated by the processing unit 12 in the monitoring device 111 (ID4) with the node ID “4” is T4 = (Tm / n) × 4.

  Note that the processing unit 12 in each monitoring device 111 may calculate the standby time T by a calculation method other than the calculation method described above.

  For example, when the number of the monitoring devices 111 included in the monitoring system 301 is k (<n), which is smaller than the maximum number n, the processing unit 12 in each monitoring device 111 has each The waiting time T may be calculated so that the transmission timing of the monitoring device 111 is shifted by Tm / k. That is, the processing unit 12 may calculate T = (Tm / k) × x as the standby time T when the node ID of its own monitoring device 111 is “x”.

  Further, the processing unit 12 in each monitoring device 111 may calculate the standby time T by using not only the node ID of the own monitoring device 111 but also other unique identification information.

  Further, the processing unit 12 in each monitoring device 111 described above transmits the time synchronization request Rq at the timing when the standby time T has elapsed from the timing at which the own monitoring device 111 is activated, but is not limited to such a configuration. For example, the configuration may be such that the time synchronization request Rq is transmitted at the timing when the standby time T has elapsed from the timing at which the predetermined information broadcast from the collection device 101 is received.

  Specifically, when the administrator performs a predetermined operation on the collection device 101, the collection device 101 broadcasts a time setting request Rq. When each monitoring device 111 receives the time setting request Rq broadcast from the collection device 101, each monitoring device 111 calculates the standby time T, and performs time synchronization at the timing when the standby time T has elapsed from the timing at which the time setting request Rq was received. The request Rq is transmitted to the collection apparatus 101.

(Current time setting)
Referring to FIG. 6 again, the processing unit 12 receives the time synchronization response Rs transmitted from the collection device 101 via the communication unit 14. Then, the processing unit 12 sets the current time in its own monitoring device 111 by newly setting the count value of the counter 13 based on the current time included in the received time synchronization response Rs.

  FIG. 9 is a diagram for explaining a current time setting method in the monitoring apparatus according to the embodiment of the present invention.

  With reference to FIG. 9, first, the processing unit 12 in the monitoring device 111 transmits a time synchronization request Rq to the collection device 101 at a timing when the counter 13 indicates time ts. Then, when receiving the time synchronization request Rq transmitted from the monitoring device 111, the collection device 101 acquires the current time tc, for example, by checking the count value of its own counter.

  Next, the collection device 101 transmits a time synchronization response Rs including the acquired current time tc to the monitoring device 111 that is a transmission source of the time synchronization request Rq.

  Next, when the processing unit 12 in the monitoring device 111 receives the time synchronization response Rs transmitted from the collection device 101 at the timing when the counter 13 indicates the time tr, for example, the time ts when the time synchronization request Rq is transmitted is received. The count value of the counter 13 is newly set using the current time tc included in the time synchronization response Rs and the time tr received the time synchronization response Rs.

  More specifically, when the transmission time of the time synchronization request Rq from the monitoring apparatus 111 to the collection apparatus 101 is equal to the transmission time of the time synchronization response Rs from the collection apparatus 101 to the monitoring apparatus 111, the counter 13 in the monitoring apparatus 111 And the difference td between the count value of the counter and the count value of the counter in the collection apparatus 101 is td = tc− (ts + tr) / 2.

  If the count value before the change is tb and the count value after the change is ta, ta = tb + td. Therefore, the processing unit 12 can synchronize the time between the monitoring device 111 and the collection device 101 by changing the current count value tb of the counter 13 to the count value ta.

  In the period from time ts, which is the timing at which the monitoring device 111 transmits the time synchronization request Rq, to time tr, which is the timing from when the time synchronization response Rs is received, for example, it is transmitted from each of the plurality of monitoring devices 111. Signals may interfere with each other, or a communication failure between the monitoring device 111 and the collection device 101 may occur. In such a case, the changed count value based on the time synchronization response Rs received by the monitoring device 111 at the time tr may not have sufficient accuracy.

  For this reason, for example, the processing unit 12 may check the interval from the time tr to the time ts, and may not be configured to change the count value as described above when the interval is equal to or greater than the predetermined value Th. .

(Notification of measurement results)
Referring to FIG. 6 again, when the processing unit 12 establishes time synchronization between its own monitoring device 111 and the collection device 101 by changing the count value of the counter 13, the current sensor 16 and the voltage sensor 17. The measurement information Me indicating the measurement result is transmitted to the collection apparatus 101 via the communication unit 14.

  More specifically, a periodic transmission period of the measurement information Me is set, and transmission of the measurement information Me is permitted in a transmittable period that is a part of the transmission period. The processing unit 12 in each monitoring device 111 transmits the measurement information Me at different timings in the transmittable period.

  In addition to the communication ID, the storage unit 15 further includes an ID of a destination device of a measurement information packet to be described later (hereinafter also referred to as a destination ID) and period information for calculating the transmission timing of the measurement information packet. Saved. In this example, the ID of the destination device is the ID of the collection device 101. Also, the transmission timing is set so as not to overlap with the transmission timing of the other monitoring devices 111 in the monitoring system 301 in the transmittable period, for example.

  The period information includes, for example, the reference time ts0, the length Lp of the transmittable period, the period Tpd from which the transmittable period arrives, and the time Ta from the start timing of the transmittable period to the transmission timing of the measurement information Me. As Ta, for example, a different value is set for each monitoring device 111.

  The start timing of the transmittable period is obtained, for example, by calculating ts0 + Tpd × Kn. Here, Kn is an integer greater than or equal to zero. Further, the transmission timing of the measurement information Me is obtained by calculating (ts0 + Tpd × Kn) + Ta.

  When the processing unit 12 establishes time synchronization between its own monitoring device 111 and the collection device 101, the processing unit 12 calculates the transmission timing of the measurement information Me based on the period information in the storage unit 15. Then, the processing unit 12 monitors the count value of the counter 13 and outputs a measurement command to the detection unit 11 when a predetermined time before the calculated transmission timing comes.

  The three current sensors 16 measure the current of the negative output line 1n corresponding to each of the plurality of solar battery panels 78, and output a measurement signal indicating the measurement result to the detection unit 11. The current sensor 16 may measure a current flowing through the plus side output line 1p.

  The voltage sensor 17 measures the voltage of the output line 5 and outputs a measurement signal indicating the measurement result to the detection unit 11.

  For example, when the measurement unit 11 receives a measurement command from the processing unit 12, the detection unit 11 performs signal processing such as averaging and filtering on each measurement signal received from each current sensor 16 and voltage sensor 17 in accordance with the received measurement command. The converted signal is converted into a digital signal, and the converted digital signal is output to the processing unit 12 as a response to the measurement command.

  The processing unit 12 creates measurement information Me indicating the measurement result regarding the corresponding solar cell panel 78. More specifically, the processing unit 12 includes the measurement result indicated by each digital signal received from the detection unit 11, the ID of the corresponding current sensor 16, the ID of the voltage sensor 17, and the communication ID of its own monitoring device 111. Measurement information Me including is created.

  When the transmission timing of the measurement information Me arrives, the processing unit 12 acquires a destination ID from the storage unit 15, and creates a measurement information packet in which the transmission destination ID is the destination ID and the data portion is the measurement information Me. Then, the processing unit 12 transmits the created measurement information packet to the collection device 101 via the communication unit 14 at intervals of the period Tpd.

  In addition, the process part 12 should just transmit the measurement information Me in the timing included in a transmission possible period, and does not need to transmit the measurement information Me periodically.

(Resending time synchronization request)
For example, when the length from the time ts that is the transmission timing of the time synchronization request Rq to the time tr that is the reception timing of the time synchronization response Rs is greater than or equal to a predetermined value Th, the processing unit 12 transmits the time synchronization request Rq. If the time synchronization response Rs is not received within a predetermined time later, the time synchronization request Rq is retransmitted.

  Here, when a period in which the time synchronization request Rq is retransmitted by a certain monitoring apparatus 111 overlaps with a period in which the measurement information Me is transmitted by another monitoring apparatus 111, the monitoring apparatus 111 transmits the time synchronization request Rq. Signals may interfere with each other. For this reason, the retransmission timing of the time synchronization request Rq by the processing unit 12 is set so as to be included in a period in which the measurement information Me is not transmitted by the other monitoring devices 111.

  FIG. 10 is a diagram illustrating an example of the transmission timing of measurement information from each monitoring apparatus and the retransmission timing of the time synchronization request according to the embodiment of the present invention.

  Referring to FIG. 10, the period Tpd at which the above-described transmission period of measurement information Me arrives is set to a value larger than the length Lp of the transmission period. That is, in the period Tpd, a transmission prohibition period, which is a period in which the measurement information Me is not transmitted by each monitoring device 111, is provided.

  For example, the processing unit 12 periodically resends the time synchronization request Rq until the time synchronization between the own monitoring device 111 and the collection device 101 is established. Assuming that the retransmission cycle, which is the retransmission interval of the time synchronization request Rq, is Trd, the retransmission cycle Trd is set based on the length Lst of the transmission prohibited period and the transmission cycle Tpd of the measurement information Me.

  For example, the retransmission period Trd of the time synchronization request Rq is set so that the retransmission timing of the time synchronization request Rq is included in the transmission prohibited period at least once within a predetermined synchronization period Tsp including a plurality of transmission periods Tpd of the measurement information Me. Is set.

  Specifically, it is assumed that the node IDs of the respective monitoring devices 111 provided in the monitoring system 301 are “1” to “n”. In addition, the monitoring device 111 (IDx) whose node ID is “x” (x is an integer greater than or equal to 1 and less than or equal to k) has not established time synchronization with the collection device 101, and the other monitoring devices 111 collect It is assumed that time synchronization with the apparatus 101 has been established.

  Further, it is assumed that the transmission period Tpd of the measurement information Me is set to 1 minute, the length Lp of the transmittable period is 45 seconds, and the length Lst of the transmission prohibited period is 15 seconds. Furthermore, it is assumed that the length of the synchronization period Tsp is 3 minutes and the retransmission cycle Trd of the time synchronization request Rq is set to 45 seconds.

  In this case, the retransmission timing of the time synchronization request Rq by the monitoring device 111 (IDx) whose node ID is “x” arrives four times in the synchronization period Tsp, and one of these four times is transmission of the measurement information Me. It will be included in the prohibition period.

  The time synchronization request Rq transmitted from the monitoring device 111 (IDx) at the timing included in the transmission prohibition period does not interfere with the measurement information Me transmitted from the other monitoring device 111, and thus reaches the collection device 101. The possibility increases. As a result, the possibility of establishing time synchronization between the monitoring device 111 (IDx) and the collection device 101 can be increased.

  Note that the retransmission timing of the time synchronization request Rq is not limited to the setting included in the transmission prohibition period as illustrated in FIG. 10 and may be set so as not to be included in the transmission prohibition period. Further, the retransmission timing of the time synchronization request Rq may not be set to a periodic timing.

  Further, a setting may be made such that a plurality of retransmission timings of the time synchronization request Rq are respectively included in a plurality of transmission prohibition periods. In this case, the synchronization period Tsp matches the transmission period Tpd of the measurement information Me.

  By the way, in the monitoring system for photovoltaic power generation like the system of patent document 1, a some measurement apparatus is provided and each measurement apparatus measures the solar cell panel corresponding to self. And if the measurement data of the predetermined period by each measuring device are compared, the failure of a solar cell panel, etc. can be detected. In this case, in order to synchronize the time between a plurality of measuring devices, information on time is transmitted and received between each measuring device and the management device, so that time synchronization processing is performed between each measuring device and the management device. Is done.

  Such time synchronization processing is performed, for example, after each measurement device is activated, and each measurement device is often activated at almost the same timing in response to power supplied from the solar battery panel. Signals transmitted to the management device from each other interfere with each other. In such a case, there is a high possibility that it takes a long time to complete the time synchronization processing with the management apparatus in all measurement apparatuses.

  On the other hand, in the monitoring system 301 according to the embodiment of the present invention, one or a plurality of monitoring devices 111 perform measurement related to the solar cell panel 78. Each monitoring device 111 transmits a time synchronization request Rq to the collection device 101. The collection device 101 receives the time synchronization request Rq transmitted from each monitoring device 111 and transmits a time synchronization response Rs including the current time to each monitoring device 111. Each monitoring device 111 receives the time synchronization response Rs transmitted from the collection device 101, and sets its current time based on the current time included in the time synchronization response Rs. Each monitoring device 111 transmits a time synchronization request Rq to the collection device 101 at a timing based on its own node ID.

  With such a configuration, it is possible to prevent the time synchronization requests Rq transmitted from the respective monitoring devices 111 from interfering with each other and to increase the possibility of reaching the collection device 101. The possibility of establishing time synchronization between them can be increased. As a result, it can be prevented that it takes a long time to establish time synchronization. Therefore, in the configuration for collecting the measurement results related to the solar battery panel 78 by each device, time synchronization between the devices can be established early.

  In the monitoring system 301 according to the embodiment of the present invention, each monitoring device 111 transmits measurement information Me indicating the measurement result to the collection device 101. In addition, a periodic transmission period of the measurement information Me is set, and transmission of the measurement information Me from each monitoring device 111 is permitted in a transmittable period that is a part of the transmission period. Further, the monitoring device 111 can retransmit the time synchronization request Rq, and one or a plurality of retransmission timings of the time synchronization request Rq by the monitoring device 111 are included in the transmission prohibition period that is a period other than the transmission possible period. Set to

  With such a configuration, there is an opportunity to transmit the time synchronization request Rq that does not interfere with the measurement information Me, so that the possibility that the time synchronization request Rq reaches the collection apparatus 101 can be increased.

  In the monitoring system 301 according to the embodiment of the present invention, each monitoring device 111 periodically resends the time synchronization request Rq.

  With such a configuration, the retransmission timing of the time synchronization request Rq can be easily adjusted by setting the retransmission cycle Trd of the time synchronization request Rq.

  In the monitoring system 301 according to the embodiment of the present invention, the retransmission cycle Trd of the time synchronization request Rq is a time synchronization request at least once within a predetermined synchronization period Tsp including a plurality of transmission cycles Tpd of the measurement information Me. Rq retransmission timing is set to be included in the transmission prohibited period.

  With such a configuration, it is possible to provide an opportunity that the time synchronization request Rq does not reliably interfere with the measurement information Me in a predetermined plurality of transmission cycles.

  Moreover, the monitoring apparatus 111 which concerns on embodiment of this invention performs the measurement regarding the solar cell panel 78. FIG. The communication unit 14 transmits a time synchronization request Rq and receives a time synchronization response Rs including the current time. Then, the processing unit 12 sets the current time in its own monitoring device 111 based on the current time included in the time synchronization response Rs received by the communication unit 14. Further, the communication unit 14 transmits a time synchronization request Rq at a timing based on the node ID of its own monitoring device 111.

  With such a configuration, it is possible to prevent the time synchronization requests Rq transmitted from the respective monitoring devices 111 from interfering with each other and to increase the possibility of reaching the collection device 101. The possibility of establishing time synchronization between them can be increased. As a result, it can be prevented that it takes a long time to establish time synchronization. Therefore, in the configuration for collecting the measurement results related to the solar battery panel 78 by each device, time synchronization between the devices can be established early.

  The above embodiment should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The above description includes the following features.

[Appendix 1]
One or more monitoring devices for measuring solar panels,
A collecting device,
Each of the monitoring devices transmits a time synchronization request to the collection device,
The collection device receives the time synchronization request transmitted from each monitoring device, and transmits a time synchronization response including the current time to each monitoring device,
Each monitoring device receives the time synchronization response transmitted from the collection device, sets its current time based on the current time included in the time synchronization response,
Each monitoring device transmits the time synchronization request to the collection device at a timing based on its own identification information,
When the monitoring device starts upon receiving power supplied from the solar panel, it uses its own node ID (Identification) to calculate a standby time from its own start timing to the time synchronization request transmission timing, A monitoring system that transmits the time synchronization request to the collection device at a timing when the standby time has elapsed from the activation timing.

[Appendix 2]
A monitoring device for measuring solar panel,
A transmission unit for transmitting a time synchronization request;
A receiver for receiving a time synchronization response including the current time;
Based on the current time included in the time synchronization response received by the receiver, a setting unit that sets the current time in the monitoring device of itself,
The transmission unit transmits the time synchronization request at a timing based on identification information of the monitoring device of the self,
Furthermore, a storage unit for storing a node ID (Identification) of the monitoring device of itself is provided,
When the monitoring device starts when receiving the power supplied from the solar battery panel, the setting unit uses the node ID stored in the storage unit to start the monitoring device from the startup timing of the monitoring device. Calculate the waiting time until the time synchronization request transmission timing,
The monitoring device, wherein the transmission unit transmits the time synchronization request at a timing when the standby time calculated by the setting unit has elapsed from the activation timing.

1, 2, 5 Output line 3 Internal line 6 Container 7 Copper bar 8 PCS
9 Power Conversion Unit 11 Detection Unit 12 Processing Unit (Setting Unit)
13 Counter 14 Communication unit (receiver and transmitter)
DESCRIPTION OF SYMBOLS 15 Memory | storage part 16 Current sensor 17 Voltage sensor 19 DC / DC converter 26 Power supply line 46 Signal line 60 Current collection unit 71 Current collection box 72 Copper bar 75 Solar cell unit 76 Connection box 77 Copper bar 78 Solar cell panel 101 Collection apparatus 111 Monitoring Device 151 Management device 301 Monitoring system 401 Solar power generation system

Claims (5)

One or more monitoring devices for measuring solar panels,
A collecting device,
Each of the monitoring devices transmits a time synchronization request to the collection device,
The collection device receives the time synchronization request transmitted from each monitoring device, and transmits a time synchronization response including the current time to each monitoring device,
Each monitoring device receives the time synchronization response transmitted from the collection device, sets its current time based on the current time included in the time synchronization response,
Each of the monitoring devices transmits the time synchronization request to the collection device at a timing based on its own identification information. Each of the monitoring devices transmits measurement information indicating the result of the measurement to the collection device,
A periodic transmission period of the measurement information is set, and transmission of the measurement information from each monitoring device is permitted in a transmittable period that is a part of the transmission period.
The monitoring device is capable of resending the time synchronization request,
The monitoring system according to claim 1, wherein one or a plurality of retransmission timings of the time synchronization request by the monitoring device are set to be included in a transmission prohibition period that is a period other than the transmittable period.   The monitoring system according to claim 2, wherein each of the monitoring devices periodically resends the time synchronization request.   The monitoring system according to claim 3, wherein the retransmission period is set so that the retransmission timing is included in the transmission prohibition period at least once within a predetermined synchronization period including a plurality of the transmission periods. A monitoring device for measuring solar panel,
A transmission unit for transmitting a time synchronization request;
A receiver for receiving a time synchronization response including the current time;
Based on the current time included in the time synchronization response received by the receiver, a setting unit that sets the current time in the monitoring device of itself,
The transmitting device transmits the time synchronization request at a timing based on identification information of the monitoring device of its own.

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