KR101234616B1 - Photo voltaic array monitoring system and method based on sensor network - Google Patents

Photo voltaic array monitoring system and method based on sensor network Download PDF

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KR101234616B1
KR101234616B1 KR1020110018912A KR20110018912A KR101234616B1 KR 101234616 B1 KR101234616 B1 KR 101234616B1 KR 1020110018912 A KR1020110018912 A KR 1020110018912A KR 20110018912 A KR20110018912 A KR 20110018912A KR 101234616 B1 KR101234616 B1 KR 101234616B1
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solar
solar module
module
current
array
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KR1020110018912A
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Korean (ko)
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KR20120100184A (en
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이상도
박상돈
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(주) 파이시스네트웍스
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy

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Abstract

The present invention can provide a monitoring system capable of monitoring the performance of the solar array, detecting a failure of the solar array, and in particular, can provide a monitoring system based on a low power sensor network to enable monitoring from a remote location.
According to the present invention, a low-power sensor network-based solar array monitoring system includes: a solar array including a plurality of solar modules for producing electrical energy from sunlight; A solar module measuring device configured to generate sensing information by sensing an output voltage or current from the plurality of solar modules; A relay node collecting sensing information from the solar module measuring device; And a monitoring server for monitoring the solar array based on the sensing information.

Description

Solar array monitoring system and method based on low power sensor network {PHOTO VOLTAIC ARRAY MONITORING SYSTEM AND METHOD BASED ON SENSOR NETWORK}

The present invention is a low-power sensor network-based solar array monitoring system and method, and in particular, having a sensor for measuring the output value of the solar module constituting the solar array and the solar radiation and temperature value for the surrounding environment of the solar array The present invention relates to a system and method for processing the information measured by a sensor and monitoring the operation of a solar array in a higher system through a low power sensor network.

Photovoltaic is a part of renewable energy to solve the problems caused by the use of fossil fuels.So, many countries around the world have built photovoltaic power generation system using solar light, and have unlimited energy and pollution-free solar light. R & D is actively in progress to use as a countermeasure for diversification of future energy sources.

In particular, Korea lacks resources and it is absolutely necessary to disseminate renewable energy. In addition, it is necessary to actively introduce solar power generation systems for the purpose of preventing environmental pollution.

However, in the case of photovoltaic facilities, the photovoltaic modules, which are the main components, are distributed through in-house testing by manufacturers and performance certification by performance certification institutes, so the reliability of the products is guaranteed, but for the photovoltaic array composed of individual photovoltaic modules Since there is no appropriate monitoring method, power generation efficiency may be greatly reduced due to the site construction status of the solar array and defects of the solar module.

In other words, the diagnosis system that measures the performance of the photovoltaic power generation facilities and determines the abnormality of the photovoltaic power generation facilities is underdeveloped. Therefore, it is urgent to develop a technology capable of checking the performance of the photovoltaic array. to be.

In addition, the solar array is subject to the constraint that the solar light must be installed directly, the problem that the labor and effort of the worker is accompanied to check the solar array when the solar power generation system is located at a long distance have.

The present invention devised to solve the above problems is an object of the present invention to monitor the performance of the solar array, and to provide a monitoring system that can detect the failure of the solar array.

In addition, there is another purpose to provide a system that can be monitored remotely, and in particular to provide a low-power remote monitoring system based on a low-power sensor network.

According to the present invention, a low-power sensor network-based solar array monitoring system includes: a solar array including a plurality of solar modules for producing electrical energy from sunlight; A solar module measuring device configured to generate sensing information by sensing an output voltage or current from the plurality of solar modules; A relay node collecting sensing information from the solar module measuring device; And a monitoring server for monitoring the solar array based on the sensing information.

According to the present invention, a low-power sensor network-based solar array monitoring method includes: sensing information generation step (S1) of generating sensing information by sensing an output voltage or a current from a solar module constituting a solar array; Collecting the sensing information at a relay node (S2); And a monitoring step (S3) in which a monitoring server receives sensing information from the relay node and monitors an operating state of the solar array.

The present invention has the effect of providing a monitoring system that can monitor the performance of the solar array and detect the failure of the solar array.

In addition, by providing a system that can be monitored remotely, there is an advantage to build a system that can monitor the solar array without the problem of manpower and time consumption.

1 is a low-power sensor network based solar array monitoring system according to an embodiment of the present invention,
2 is a block diagram of a solar array in accordance with aspects of the present invention.
3 is a block diagram of a solar module sensing device according to an aspect of the present invention;
4 is an exemplary view of connecting a photovoltaic module measuring device by grouping a photovoltaic array;
5 is an exemplary diagram of a network configuration of a solar array monitoring system, and
6 is a flowchart of a low power sensor network based solar array monitoring method according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings, the same reference numerals are used to designate the same or similar components, and the same reference numerals will be used to designate the same or similar components. Detailed descriptions of known functions and configurations are omitted.

1 is a low-power sensor network based solar array monitoring system according to an embodiment of the present invention.

Referring to FIG. 1, a low power sensor network-based solar array monitoring system includes a solar array 10, a solar module sensing device 200, a relay node 300, and a monitoring server.

The solar array 10 is the main measurement object in the present invention, the solar array 10 is configured by connecting a plurality of solar modules 100 in series / parallel. Each photovoltaic module 100 is a collection of unit photovoltaic cells that produce electrical energy by photoelectric conversion.

Power generated by the solar array 10 may be used to charge the battery 14 or may be supplied to the power system through the inverter 16. 2 is a schematic diagram showing the overall configuration of a photovoltaic system, wherein the battery 14 is charged with electrical energy of the photovoltaic array 10 when daytime or sunshine is good, and then is charged at night or on a cloudy day. In addition, the inverter 16 converts the direct current power of the solar power system into an alternating current power to supply power to loads requiring the alternating current power. The power controller 12 controls the overall power supply method of the photovoltaic power generation system and processes a charge control function for charging the battery 14 with electricity of the solar array.

The photovoltaic module sensing device 200 generates sensing information about the voltage and current output state of each photovoltaic module 100 and the surrounding environment of the photovoltaic array 10 and transmits the generated sensing information to a higher system. It is a small wireless transceiver on a sensor network.

3 is a block diagram of a solar module sensing device according to an aspect of the present invention. Referring to FIG. 3, the solar module sensing device 200 includes a sensor unit 210, an A / D converter 220, a central processing unit 230, and a communication module 240.

The sensor unit 210 detects a charging state of the solar array 10, and is installed near the solar array 10 installed at a site to detect sensing of the surrounding environment of the solar array 10 to generate sensing information. It is wealth. The sensor unit 210 is configured of a plurality of sensors to generate sensing information about the state of the solar array 10 and the environment around the solar array 10.

The sensor unit 210 includes a voltage detection sensor 212 for detecting an output voltage of the solar array 10 or a current detection sensor 214 for detecting an output current. The detected voltage detection value and the current detection value are used as an index to compare whether each module of the solar array 10 is operating normally.

In addition, the sensor unit 210 is installed near the photovoltaic array 10 installed at the measurement site, the solar radiation sensor 216 for detecting the amount of solar radiation, and two temperatures for sensing the solar array module temperature and the ambient temperature of the site It may further include a sensor 218. At this time, each sensor of the sensor unit 210 should be installed in a loading place so as to detect the output voltage and output current of the solar module 100, the environment around the solar array 10, the installation location After being installed outside the enclosure of the photovoltaic module sensing device 200 so as not to be bound to, and may be connected to the A / D converter 220 inside the enclosure via a connection cable.

The sensing information generated through the sensor unit 210 is input to the A / D converter 220 in turn through the multiplexer, and the A / D converter 220 is connected to the sensor unit 210 so that the sensor unit 210 is connected to the sensor unit 210. It converts the sensed analog data into digital data suitable for communication environment.

The central processing unit 230 processes the digital signal input from the A / D converter 220 into a signal suitable for communication.

The communication module 240 transmits the digitally converted sensing information to the relay node 300 according to the request of the relay node 300. The data communication method between the communication module 240 and the relay node 300 may use a wireless network applying a low power Zigbee protocol, which is a general communication method supported by a sensor network, but is not limited thereto.

In the solar module sensing device 200, the voltage detection sensor 212 or the current detection sensor 214 may be attached to each solar module 100 constituting the solar array 10. By being attached to the solar module 100 individually, it can be determined whether each of the solar modules 100 provides a normal output.

Alternatively, the photovoltaic module 100 constituting the photovoltaic array 10 may be grouped in any number, and a voltage detecting sensor 212 or a current detecting sensor 214 capable of determining an output state for each group may be used. It may be.

For example, as shown in FIG. 4, in the plurality of solar modules 100 connected in series, an open voltage is derived by attaching a voltage detection sensor 212 to the ends of the solar modules connected in series, or connected in series. By measuring the short-circuit current of the optical module, it is possible to determine whether the output value of the grouped photovoltaic module 100 is normal.

In this case, when grouping the photovoltaic module 100, each group preferably has the same number of photovoltaic modules 100 and have the same electrical connection state. This is to easily detect the abnormality of the photovoltaic array 10 by selecting a group in which any one of the photovoltaic modules 100 operates abnormally and generates a smaller output value than other groups.

When grouping the photovoltaic module 100, there is an economic advantage that can not accurately identify the photovoltaic module 100 that has a failure, but can build a monitoring system using fewer sensors.

The relay node 300 is connected to the plurality of solar module sensing devices 200 to collect sensing information and transmit the collected sensing information to the monitoring server. The relay node 300 serves as a communication relay device between the solar module sensing device 200 and the monitoring server.

The monitoring server 400 collects sensing information from the relay node 300 and monitors the operation state of the solar array 10. The monitoring server 400 may remotely monitor matters related to the amount of power output to the power system or the amount of power charged by the battery 14 and the surface temperature of the solar array 10 through the solar array 10.

Monitoring server 400 and the relay node 300 may be connected via a wired or wireless network, it is preferable to use an Ethernet-based LAN or WLAN that supports the TCP / IP protocol.

In addition, the monitoring server 400 may diagnose the failure of the solar module 100 based on sensing information such as a voltage detection value, a current detection value, an insolation amount, and a temperature measurement value.

For example, by examining whether there is a photovoltaic module 100 having a voltage output value or a current output value smaller than that of other photovoltaic modules 100, it is determined whether the photovoltaic module 100 has failed or is estimated based on the amount of solar radiation and temperature. The failure is determined by checking the solar module 100 having an output lower than the voltage or current output value.

At this time, the monitoring server 400 writes the expected output value of the photovoltaic module 100 according to the amount of insolation and the ambient temperature into a look up table (LUT) and stores the result in a memory, and then measures the measured insolation and temperature values. The abnormality of the solar module 100 may be determined by checking whether a corresponding voltage or current output value is output from the solar module.

According to another embodiment of the present invention, the central processing unit 230 of the solar module sensing device 200 compares the voltage or current value input through the solar module 100 itself of the solar module 100 It may be determined whether there is an error, and the determination result may be transmitted to the relay node 300.

In the solar array 10, each solar module 100 is typically placed under the same conditions at the same amount of solar radiation and temperature except for the effects of partially occurring shadows, so that the individual solar modules 100 output The voltage or current to be made is at a similar level. Therefore, the measured voltage or current value is connected to a comparator (not shown), and an error signal is generated when an error larger than a predetermined range occurs, thereby preventing abnormality in the photovoltaic module 100. It can be detected.

The detected error signal is transmitted to the monitoring server 400 through the relay node 300, so that the monitoring server 400 can easily identify that an error has occurred.

FIG. 5 is an exemplary network configuration of a solar array monitoring system. In order to form an entire network, a network is formed by merging a star topology and a tree topology.

The monitoring server 400 and the relay node 300 establish a star network to transmit sensing information collected from the plurality of relay nodes 300 to the monitoring server, and connect the solar module sensing device 200 to the tree network. Form the entire network merged form.

In such a network, a low power network may be configured by applying a synchronization scheme in connection between nodes. The relay node 300, which is constantly supplied with power, transmits a synchronization packet at a predetermined time interval. Each sensor of the solar module sensing device 200 which is normally idle is operated by receiving a synchronization packet. In this case, the idle time of the photovoltaic module sensing device 200 may be adjusted by the monitoring server, and the control signal may be transmitted to all the relay nodes 300 through the monitoring server. The photovoltaic module sensing device 200 receives a synchronization packet and operates each sensor to transmit a measured value.

In this case, since the time required to calculate the measured value varies depending on the type of sensor used in the solar module sensing device 200, it is important to accurately synchronize the synchronization to apply the synchronization technique to all the sensors.

For example, since the sensor measuring the amount of insolation and temperature takes longer than the sensor that detects the voltage or current, the sensor operates according to the characteristics of the sensor before the time required to calculate the measured value is measured and then receives the synchronization packet. You will have to.

In FIG. 5, the network configuration is described as having a tree type and a star type topology, but the present invention is not intended to limit the present invention, and the present invention may be applied to various types of network topologies such as mesh type, full connected type, and ring type.

6 is a flowchart of a low power sensor network based solar array monitoring method according to an embodiment of the present invention.

Referring to FIG. 6, the solar array monitoring method is performed according to the following flow.

Sensing information generation step (S601) the solar module sensing device 200 detects the surface temperature, output voltage value and current value of each module from the solar module 100 constituting the solar array 10, In this step, the solar module 100 generates sensing information by detecting surrounding environmental conditions such as insolation, atmospheric temperature, and the like.

In the sensing information collecting step (S602), the relay node 300 collects sensing information generated from the plurality of solar module sensing devices 200. The sensing information may be periodically collected at predetermined time intervals, and a collection cycle may be set through the monitoring server.

The monitoring step (S603) is a step in which the monitoring server receives the sensing information from the relay node 300 to monitor the operating state of the solar array 10.

The failure determination step (S604) is a step in which the monitoring server diagnoses a failure of the solar module 100 based on sensing information such as a voltage detection value, a current detection value, an insolation amount, and a temperature measurement value. Compare the voltage detection value or the current detection value between the photovoltaic module 100 to screen out the abnormal photovoltaic module 100, or the voltage or current value output from the photovoltaic module 100 is measured to the measured solar radiation and temperature. If it is smaller than the normal output value of the corresponding solar module 100, it can be determined that the solar module 100 is a failure.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

10 solar array 12 power controller
14 battery 16 inverter
100: solar module 200: solar module measuring device
210: sensor 220: A / D converter
230: central processing unit 240: communication module
300: relay node 400: monitoring server

Claims (9)

A solar array comprising a plurality of solar modules producing electrical energy from sunlight;
A solar module measuring device configured to generate sensing information by sensing an output voltage or current from the plurality of solar modules;
A relay node collecting sensing information from the solar module measuring device; And
And a monitoring server for monitoring the solar array based on the sensing information.
The solar module measuring device,
A voltage detection sensor measuring an output voltage of the solar module or a current detection sensor measuring an output current of the solar module; And
Including a solar radiation sensor for measuring the amount of solar radiation and a temperature sensor for measuring the ambient temperature of the solar array,
The monitoring server,
The normal output voltage value or output current value of the solar module with respect to the solar radiation measured by the solar radiation sensor and the ambient temperature measured by the temperature sensor is stored as a lookup table, and whether the solar module is broken based on the lookup table Low-power sensor network-based solar array monitoring system, characterized in that for determining.
delete delete The method of claim 1, wherein the monitoring server,
A low power sensor network based solar array monitoring system, characterized in that to determine whether the failure of the solar module by comparing the output voltage or current between the solar modules.
delete According to claim 1, The solar module measuring device,
A low power sensor, characterized in that it further comprises a comparator for comparing the output voltage or current between the photovoltaic module, and generates an error signal when an error occurs when the comparison value of the output voltage or current is larger than a preset value. Network based solar array monitoring system.
The method of claim 1, wherein the relay node,
And transmitting the synchronization packet to the solar module measuring device, wherein the solar module measuring device receives the synchronization packet to generate the sensing information.
delete delete
KR1020110018912A 2011-03-03 2011-03-03 Photo voltaic array monitoring system and method based on sensor network KR101234616B1 (en)

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