A combiner box monitoring system based on optical fiber ring network

Abstract

The present invention relates to a junction box monitoring system based on an optical fiber ring network. The system includes a plurality of junction box monitors installed in each junction box and a box transformer communication management machine installed in a box transformer, the junction box monitor and the box transformer communication management machine each include a first optical fiber module and a second optical fiber module, the first optical fiber module and the second optical fiber module connect each junction box monitor and the box transformer communication management machine end to end through optical fiber, so that each junction box monitor has two communication loops connected to the box transformer communication management machine. The present invention uses optical fiber for communication, which can solve the communication problem between the junction box monitor and the box transformer communication management machine in the photovoltaic production area, and can also effectively avoid electromagnetic interference from other power equipment and prevent lightning strikes from damaging electronic devices. The configuration of the ring network can also be used as communication channel redundancy to improve reliability.

Description

Technical Field

[0001] The invention relates to the field of photovoltaic monitoring, and in particular to a combiner box monitoring system based on an optical fiber ring network. Background Art

[0002] With the large-scale construction of domestic photovoltaic power stations, the proportion of photovoltaic power generation in the entire power supply has gradually increased, and the safety monitoring of photovoltaic power stations has gradually received attention from operating companies. At present, the monitoring of photovoltaic production areas is mainly completed by combiner box monitoring and box transformer measurement and control. The photovoltaic production area is composed of many photovoltaic modules and the area is wide. Therefore, reliable communication between smart devices is a key issue that needs to be solved in the monitoring of photovoltaic power station production areas.

[0003] The communication between the current mainstream box-type transformer measurement and control device and the monitoring background is realized by the Ethernet fiber ring network of the box-type transformer communication management machine, but the communication between the junction box monitor and the box-type transformer communication management machine is generally carried out by RS485 or wireless communication. One of the main equipment of a photovoltaic power station is the inverter. When the inverter is working, it will generate a large number of high-order harmonics, which will cause great electromagnetic pollution to the power grid and space, seriously affecting RS485 and wireless communication, and bringing communication risks to accurate and reliable monitoring. In addition, the production area of ​​the photovoltaic power station is often not unified due to its large scope during construction, and the lightning protection measures are not perfect, which also brings great hidden dangers to communication, often causing the entire network to lose connection on thunderstorm days.

[0004] In view of the above situation, there is an urgent need to develop a combiner box monitoring system that solves the above problems. Summary of the invention

[0005] The purpose of the present invention is to solve the communication problem of the combiner box monitor in the photovoltaic production area, and propose a combiner box monitoring system based on the optical fiber ring network. The system uses optical fiber for communication, which can effectively avoid electromagnetic interference from other power equipment and prevent lightning strikes from damaging electronic devices. The configuration of the ring network can also be used as communication channel redundancy to improve reliability.

[0006] To achieve the above-mentioned purpose, the present invention provides a junction box monitoring system based on an optical fiber ring network. The system includes a junction box monitor and a box transformer communication management machine, wherein the junction box monitor includes multiple ones, each installed in an outdoor junction box, and used to collect string current, parallel voltage and environmental temperature and humidity information entering each junction box; the box transformer communication management machine is installed in an outdoor box transformer, and used to collect information from the junction box monitor to achieve protocol conversion; wherein the junction box monitor and the box transformer communication management machine each include a first optical fiber module and a second optical fiber module, and the first optical fiber module and the second optical fiber module connect each junction box monitor to the box transformer communication management machine end to end through optical fibers, so that each junction box monitor has two communication loops connected to the box transformer communication management machine.

[0007] Furthermore, the combiner box monitor also includes: a current transformer, a voltage transformer, a temperature and humidity sensor, an ADC chip, a CPU chip, an open-in optocoupler, a display, a keyboard and a photovoltaic power supply.

[0008] The current transformer, voltage transformer and temperature and humidity sensor are respectively connected to the ADC chip, and are used to convert the current, voltage and ambient temperature and humidity signals of the photovoltaic module into weak voltage signals suitable for reading by the ADC chip;

[0009] The ADC chip is connected to the CPU chip and is used to perform analog-to-digital conversion on the weak voltage signal read by the ADC chip and then send it to the CPU chip;

[0010] The CPU chip is connected to the input optical coupler, the keyboard and the display, and is used to read the data information of the ADC chip, the input optical coupler and the keyboard, and display it on the display, and transmit it to the outside through the first optical fiber module and the second optical fiber module;

[0011] The photovoltaic power source is used to supply power to the monitor.

[0012] Furthermore, the first fiber optic module in the combiner box monitor is connected to the second fiber optic module in the adjacent combiner box monitor or the box transformer communication manager through optical fiber, and the first fiber optic module in the box transformer communication manager is connected to the second fiber optic module in the adjacent photovoltaic power optimizer.

[0013] Furthermore, the first fiber optic module in the combiner box monitor is connected to the first fiber optic module in the adjacent combiner box monitor or the box transformer communication management machine through optical fiber, and the second fiber optic module in the combiner box monitor is connected to the second fiber optic module in the adjacent combiner box monitor or the box transformer communication management machine through optical fiber.

[0014] The combiner box monitoring system based on optical fiber ring network proposed in the present invention has the following beneficial effects:

[0015] 1. Fiber optic communication will not receive electromagnetic interference from other power equipment;

[0016] 2. When lightning strikes a communication line, the overvoltage will not be transmitted along the optical fiber to the weak current equipment;

[0017] 3. The communication rate is much higher than traditional RS485 communication or wireless communication;

[0018] 4. The topological structure of the ring network can prevent the damage of a certain communication line from causing the device to lose connection;

[0019] 5. Fiber optic communication achieves electrical isolation between devices, and damage to a single device will not affect the communication of other devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of a combiner box monitor based on an optical fiber ring network of the present invention;

[0021] Figure 2 It is a structural block diagram of a combiner box monitoring system based on an optical fiber ring network of the present invention;

[0022] Figure 3 It is a structural block diagram of another combiner box monitoring system based on optical fiber ring network of the present invention;

[0023] Description of reference numerals:

[0024] 1-current transformer, 2-voltage transformer, 3-temperature and humidity sensor, 4-ADC chip, 5-CPU chip, 6-open-in optocoupler, 7-keyboard, 8-display, 9-photovoltaic power supply, 10-combiner box monitor, 11-combiner box monitor, 12-combiner box monitor, 13-combiner box monitor, 14-combiner box monitor, 15-box transformer communication management machine, 16 first optical fiber module, 17-second optical fiber module, 18-optical fiber, 19-optical fiber, 20-optical fiber, 21-optical fiber, 22-optical fiber, 23-optical fiber. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention, and to make the above-mentioned purposes, features and advantages of the embodiments of the present invention more obvious and easy to understand, the technical solutions of the present invention are further described in detail below through the accompanying drawings and embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0026] Figure 1 It is a structural block diagram of a combiner box monitor based on an optical fiber ring network according to an embodiment of the present invention.

[0027] like Figure 1 As shown, the combiner box monitor in this embodiment includes a current transformer 1, a voltage transformer 2, a temperature and humidity sensor 3, an ADC chip 4, a CPU chip 5, an input optical coupler 6, a display 7, a keyboard 8, a photovoltaic power supply 9, a first optical fiber module 16 and a second optical fiber module 17.

[0028] The current transformer 1 , the voltage transformer 2 , and the temperature and humidity sensor 3 are respectively connected to the ADC chip 4 and are responsible for converting the current, voltage, and ambient temperature and humidity signals of the photovoltaic module into weak voltage signals suitable for reading by the ADC chip 4 .

[0029] The ADC chip 4 is connected to the CPU chip 5 and is responsible for performing analog-to-digital conversion on the weak voltage signal read by the ADC chip 4 and then sending the converted signal to the CPU chip 5 .

[0030] The open-in optical coupler 6, display 7, keyboard 8, first optical fiber module 16 and second optical fiber module 17 are respectively connected to the CPU chip 5. The CPU chip 5 is responsible for reading the data information of the ADC chip 4, the open-in optical coupler 6 and the keyboard 8, and displaying it through the display 7, and transmitting it to the outside through the first optical fiber module 16 and the second optical fiber module 17.

[0031] The photovoltaic power source 9 is mainly used to supply power to the monitor.

[0032] Figure 2 It is a structural block diagram of the combiner box monitoring system based on the optical fiber ring network of the present invention.

[0033] like Figure 2 As shown, the combiner box monitoring system based on the optical fiber ring network of the present invention includes a combiner box monitor and a box transformer communication management machine. The combiner box monitor includes multiple combiner box monitors, and in this embodiment, there are 4 combiner box monitors, namely combiner box monitor 11, combiner box monitor 12, combiner box monitor 13 and combiner box monitor 14, each of which is installed in an outdoor combiner box and is responsible for collecting the string current, parallel voltage and environmental temperature and humidity information entering their respective combiner boxes. The box transformer communication management machine 15 is installed in the outdoor box transformer and is responsible for collecting the information of the combiner box monitor to realize protocol conversion. Among them, the combiner box monitors 11, 12, 13, 14 and the box transformer communication management machine 15 each include a first optical fiber module 16 and a second optical fiber module 17, and the first optical fiber module 16 and the second optical fiber module 17 are used to form an optical fiber ring network. The first optical fiber module 16 and the second optical fiber module 17 connect each combiner box monitor to the box transformer communication management machine end to end through optical fibers, so that each combiner box monitor has two communication loops connected to the box transformer communication management machine.

[0034] Specifically, the first optical fiber module 16 in the combiner box monitor in this embodiment is connected to the second optical fiber module 17 in the adjacent combiner box monitor or the box transformer communication manager through optical fibers 17, 18, 19, and 21. The first optical fiber module 16 in the box transformer communication manager is connected to the second optical fiber module 17 in the adjacent photovoltaic power optimizer through optical fiber 20.

[0035] During normal communication, the data of the combiner box monitor 14 connected to the second optical fiber module 17 in the box transformer communication management machine 15 is sent out from the second optical fiber module 17 inside it, and the other combiner box monitors 11, 12, and 13 send out the lower-level data received by the first optical fiber module 16 inside them together with the local data from their own second optical fiber modules 17. When an optical fiber is abnormal somewhere, for example, the optical fiber 18 is damaged, after the combiner box monitors 11 and 12 detect the damage, the combiner box monitor 11 sends out the local data from the first optical fiber module 16 connected well inside it, and the combiner box monitor 12 sends out the local data from the second optical fiber module 17 connected well inside it; at this time, the combiner box monitor 11 is connected to the box transformer communication management machine 15 through the combiner box monitor 14, and the combiner box monitor 12 is connected to the box transformer communication management machine 15 through the combiner box monitor 13, and the data of all combiner box monitors will not be lost.

[0036] Figure 3 It is a structural block diagram of another combiner box monitoring system based on optical fiber ring network of the present invention.

[0037] like Figure 3 As shown, the junction box monitoring system based on the optical fiber ring network of the present invention includes a junction box monitor and a box transformer communication management machine. The junction box monitors include multiple ones, and in this embodiment, there are 5 of them, namely, the junction box monitor 10, the junction box monitor 11, the junction box monitor 12, the junction box monitor 13 and the junction box monitor 14, each of which is installed in an outdoor junction box and is responsible for collecting the string current, parallel voltage and environmental temperature and humidity information entering their respective junction boxes. The box transformer communication management machine 16 is installed in the outdoor box transformer and is responsible for collecting the information of the junction box monitor and realizing protocol conversion. Among them, the junction box monitors 10, 11, 12, 13, 14 and the box transformer communication management machine 15 each include a first optical fiber module 16 and a second optical fiber module 17, and the first optical fiber module 16 and the second optical fiber module 17 are used to form a fiber optic ring network. The first optical fiber module 16 and the second optical fiber module 17 connect each combiner box monitor with the box-type transformer communication management machine end to end through optical fibers, so that each combiner box monitor has two communication loops connected to the box-type transformer communication management machine.

[0038] Specifically, the first optical fiber module 16 in the junction box monitor or the box transformer communication management machine in this embodiment is connected to the first optical fiber module 16 in the adjacent junction box monitor or the box transformer communication management machine through optical fibers 19, 21, and 23, and the second optical fiber module 17 in the junction box monitor or the box transformer communication management machine is connected to the second optical fiber module 17 in the adjacent junction box monitor or the box transformer communication management machine through optical fibers 18, 20, and 22.

[0039] When an optical fiber is abnormal somewhere, for example, optical fiber 18 is damaged, after the combiner box monitors 10 and 11 detect the damage, the combiner box monitor 10 sends the local data from the first optical fiber module 16 with intact internal connection, and the combiner box monitor 11 sends the local data from the first optical fiber module 16 with intact internal connection; at this time, the combiner box monitor 10 is connected to the box transformer communication management machine 15 through the combiner box monitors 13 and 14, and the combiner box monitor 11 is connected to the box transformer communication management machine 15 through the combiner box monitor 12, and the data of all combiner box monitors will not be lost.

[0040] In summary, the present invention uses optical fiber for communication, which can solve the communication problem between the junction box monitor in the photovoltaic production area and the box transformer communication management machine, and can also effectively avoid electromagnetic interference from other power equipment and prevent lightning strikes from damaging electronic devices. The ring network configuration can also be used as communication channel redundancy to improve reliability.

[0041] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A combiner box monitoring system based on optical fiber ring network, characterized in that: It includes a combiner box monitor and a box transformer communication management machine. The combiner box monitor includes multiple ones, each installed in an outdoor combiner box, and is used to collect string current, parallel voltage, and environmental temperature and humidity information entering the respective combiner boxes; the box transformer communication management machine is installed in the outdoor box transformer, and is used to collect information from the combiner box monitor to realize protocol conversion; Wherein, the combiner box monitor and the box-type transformer communication management machine each include a first optical fiber module and a second optical fiber module, and the first optical fiber module and the second optical fiber module connect each combiner box monitor and the box-type transformer communication management machine end to end through optical fiber, so that each combiner box monitor has two communication loops connected to the box-type transformer communication management machine; The combiner box monitor also includes: a current transformer, a voltage transformer, a temperature and humidity sensor, an ADC chip, a CPU chip, an open-in optocoupler, a display, a keyboard and a photovoltaic power supply. The current transformer, voltage transformer and temperature and humidity sensor are respectively connected to the ADC chip, and are used to convert the current, voltage and ambient temperature and humidity signals of the photovoltaic module into weak voltage signals suitable for reading by the ADC chip; The ADC chip is connected to the CPU chip and is used to perform analog-to-digital conversion on the weak voltage signal read by the ADC chip and then send it to the CPU chip; The CPU chip is connected to the input optical coupler, the keyboard and the display, and is used to read the data information of the ADC chip, the input optical coupler and the keyboard, and display it on the display, and transmit it to the outside through the first optical fiber module and the second optical fiber module; The photovoltaic power source is used to supply power to the monitor.

2. The combiner box monitoring system based on optical fiber ring network according to claim 1 is characterized in that: The first fiber optic module in the combiner box monitor is connected to the second fiber optic module in the adjacent combiner box monitor or box transformer communication manager through optical fiber, and the first fiber optic module in the box transformer communication manager is connected to the second fiber optic module in the adjacent photovoltaic power optimizer.

3. The combiner box monitoring system based on optical fiber ring network according to claim 1, characterized in that: The first fiber optic module in the combiner box monitor is connected to the first fiber optic module in the adjacent combiner box monitor or box transformer communication management machine through optical fiber, and the second fiber optic module in the combiner box monitor is connected to the second fiber optic module in the adjacent combiner box monitor or box transformer communication management machine through optical fiber.

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