KR102156060B1 - Communication device and photovoltaic system - Google Patents

Abstract

The present invention relates to a communication device and a solar system. A communication device according to an embodiment of the present invention includes a first communication unit for receiving AC power to which solar power information is added through a system, solar power information, and current and voltage of a power conversion module connected to the solar cell module. A memory for storing information and status information on the system, and a second communication unit for outputting monitoring information including at least one of solar power information, current and voltage information, and system status information to the outside. . This enables storage and output of monitoring information.

Description

Communication device and photovoltaic system

The present invention relates to a communication device and a solar system, and more particularly, to a communication device and a solar system capable of storing and outputting monitoring information.

Recently, as existing energy resources such as oil and coal are expected to be depleted, interest in alternative energy to replace them is increasing. Among them, solar cells are in the spotlight as a next-generation battery that directly converts solar energy into electrical energy using semiconductor devices.

Meanwhile, the solar module refers to a state in which solar cells for solar power generation are connected in series or in parallel, and the solar module may include a junction box for collecting electricity produced by the solar cells.

An object of the present invention is to provide a communication device and a solar system capable of storing and outputting monitoring information.

A communication device according to an embodiment of the present invention for achieving the above object includes a first communication unit for receiving an AC power to which solar power information is added through a system, solar power information, and power connected to the solar cell module. A memory for storing current and voltage information of the conversion module and status information on the system, and monitoring information including at least one of solar power information, current and voltage information, and status information on the system are output to the outside. It includes a second communication unit.

On the other hand, the solar system according to an embodiment of the present invention for achieving the above object, a solar cell module including a plurality of solar cells, and power to convert the direct current power supplied from the solar cell module into AC power and output power A conversion module, a first communication unit that receives AC power to which solar power information is added through the system, and a memory that stores solar power information, current and voltage information of the power conversion module, and status information on the system. , Solar power information, current and voltage information, and a communication device including a second communication unit for outputting monitoring information including at least one of status information on the system to the outside.

According to an embodiment of the present invention, a communication device includes a first communication unit for receiving AC power to which solar power information is added, through a system, solar power information, a current of a power conversion module connected to the solar cell module, and By including a second communication unit to externally output monitoring information including at least one of voltage information and a memory for storing status information on the system, solar power information, current and voltage information, and status information on the system , Monitoring information can be saved and output.

Meanwhile, the communication device may further include an output unit that outputs monitoring information, and the user can simply check monitoring information on the solar module through the output unit.

The first communication unit, based on a communication speed of 1 Mbps or more and a bandwidth of 2 to 30 MHz, receives the AC power added with solar information from the system, thereby enabling high-speed data communication, and thus, robust against noise. Is done.

Meanwhile, according to an embodiment of the present invention, the solar system includes a solar cell module, a power conversion module, and a communication device, so that the solar power information produced by the solar cell module can be stored and output from the communication device. Is done. Accordingly, user convenience can be increased.

On the other hand, the power conversion module may include a converter unit having a plurality of interleaving converters, and varying the switching period of the plurality of interleaving converters, and in response to the variable switching period, the phase difference between the plurality of interleaving converters By varying, it is possible to prevent an instantaneous output decrease due to a change in the switching frequency.

On the other hand, the interleaving operation of the plurality of interleaving converters reduces a ripple between the input current and the output current of the converter unit, and thus has an advantage of reducing the capacity and size of circuit elements in the power conversion module.

Meanwhile, the converter unit may output a pseudo DC power, and for this purpose, the switching frequency of the interleaving converter may be variable. Accordingly, it is possible to output a pseudo DC power that is closer to a sine wave.

Meanwhile, a converter unit including a plurality of interleaving converters and a power conversion module including an inverter unit may be provided in a junction box attached to a rear surface of the solar cell module. Accordingly, it is possible to stably output AC power immediately.

1 is an example of a configuration diagram of a solar system according to an embodiment of the present invention.
2 is a front view of a solar module according to an embodiment of the present invention.
3 is a rear view of the solar module of FIG. 2.
4 is an exploded perspective view of the solar cell module of FIG. 2.
5 is an example of a configuration of a bypass diode of the solar module of FIG. 2.
6 is an example of a block diagram of a power conversion module inside the junction box of FIG. 2.
7A is an example of an internal circuit diagram of the power conversion module of FIG. 6.
7A is an example of an internal circuit diagram of the power conversion module of FIG. 6.
7B is another example of an internal circuit diagram of the power conversion module of FIG. 6.
8A and 8B are views illustrating a method of operating the power conversion module of FIG. 6.
9A to 9B are views referenced for explaining the operation of the tapped inductor converter of FIG. 7A.
10A and 10B are diagrams referenced for explaining that the converter of FIG. 6 outputs a pseudo DC power using an input power source.
11 to 12 are diagrams referenced for explaining a switching frequency variation according to a switching mode of a switching element.
13 illustrates a case where a switching frequency is fixed in three interleaving converters.
14 illustrates a case in which a switching frequency is varied and a phase difference is fixed in three interleaving converters.
15 illustrates a case in which a switching frequency and a phase difference are varied in three interleaving converters.
16 is an example of an internal block diagram of the communication device of FIG. 1.
17A to 17C illustrate various examples of a communication method between the solar module of FIG. 1 and a communication device.
18 is an example of a configuration diagram of a solar system according to another embodiment of the present invention.
19A is an example of an internal circuit diagram of the power conversion module of FIG. 18.
19B is another example of an internal circuit diagram of the power conversion module of FIG. 18.
20 is an example of a configuration diagram of a solar system according to another embodiment of the present invention.
21A is an example of an internal circuit diagram of the first and second power conversion modules of FIG. 20.
21B is another example of an internal circuit diagram of the first and second power conversion modules of FIG. 20.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

The suffixes "module" and "unit" for the constituent elements used in the following description are given in consideration of only the ease of writing in the present specification, and do not impart a particularly important meaning or role by themselves. Therefore, the "module" and "unit" may be used interchangeably with each other.

1 is an example of a configuration diagram of a solar system according to an embodiment of the present invention.

Referring to the drawings, the solar system 10 of FIG. 1 includes a plurality of solar modules 50a, 50b, ..., 50n, a plurality of solar modules 50a, 50b, ..., 50n, and A communication device 800 for performing communication through a grid, a server 300 for exchanging data through the communication device 800 and the network 750, data with the communication device 800 or server 300 An exchangeable mobile terminal 600 may be provided.

Each solar module (50a, 50b, ..., 50n) is provided with a plurality of solar cells, each solar cell module (100a, 1000b, ..., 100n) for generating a DC power supply, and each solar cell A junction box 200a that is attached to the rear of the modules 100a, 1000b, ..., 100n and converts and outputs DC power from each solar cell module 100a, 100b, ..., 100n into AC power , 200b, ..., 200n).

At this time, the junction box (200a, 200b, ..., 200n) is a power conversion module (Fig. 6) that converts DC power from each solar cell module (100a, 1000b, ..., 100n) into AC power and outputs it. Of 700) may be provided.

The power conversion module (700 in FIG. 6) is on one circuit board, a bypass diode (Da, Db, Dc), a converter unit (530 in FIG. 6), an inverter unit (540 in FIG. 6), and a communication unit ( 570 of FIG. 6 may be provided. Such a power conversion module (700 in FIG. 6) may be referred to as a micro inverter.

On the other hand, in the embodiment of the present invention, a plurality of solar modules (50a, 50b, ..., 50n), each solar cell module (100a, 100b, ..., 100n) and the junction box (200a, 200b) , ...,200n), it is possible to directly output AC power, so it may be called a solar AC module.

On the other hand, according to this configuration, by attaching a micro inverter that outputs AC power to each solar cell module (100a, 1000b, ..., 100n), even if the output of any one of the solar cell modules is lowered, a plurality of The photovoltaic modules 50a, 50b, ..., 50n are connected in parallel to each other, so that it is possible to supply AC power generated by a grid (grid).

In addition, unlike the string method in which a plurality of photovoltaic modules (50a, 50b, ..., 50n) are connected in series with each other, AC power is generated and output independently of each other and is connected in parallel. Regardless of the output, it is possible to stably output AC power to the system.

On the other hand, in the embodiment of the present invention, the power conversion module (700 in FIG. 6) outputs the photovoltaic power information of the photovoltaic module to an external grid through the communication unit (570 in FIG. 6). I can.

At this time, the communication unit (570 in Fig. 6) adds a carrier frequency signal including predetermined information to the AC power converted by the inverter unit (530 in Fig. 6) by power line communication (PLC), and includes information. AC power can be output to the system.

On the other hand, the communication unit (570 in FIG. 6), when the level of the converted AC power is less than or equal to a predetermined value, may add a carrier signal including information to the predetermined DC power and output the DC power including the information to the system. have.

For example, if the solar module cannot generate DC power and there is no converted AC power, the communication unit (570 in FIG. 6) adds a carrier signal including information to a separate DC power source to provide information The DC power supply including the information may be output to the system, or the DC power including the information may be output to the system by adding a carrier signal including information to the DC power supply of the 0 level. Accordingly, even when the DC power is not generated or the level of the AC power is below a predetermined level, communication can be performed through a grid.

On the other hand, the communication unit (570 of FIG. 6) can perform one-way communication, and thus, the configuration of the power conversion module (700 of FIG. 6) can be simply configured.

The communication device 800 can each receive information from the plurality of solar modules 50a, 50b, ..., 50n by power line communication (PLC). That is, information may be received from a plurality of photovoltaic modules 50a, 50b, ..., 50n through a grid, and signal processing may be performed.

To this end, the communication device 800 includes a first communication unit (810 in Fig. 16), a control unit (820 in Fig. 16), a second communication unit (830 in Fig. 16), an output unit (840 in Fig. 16), and a power supply unit (Fig. 16 850 and a memory (860 of FIG. 16) may be provided.

The first communication unit 810 receives information such as solar power information, current and voltage information, etc. from a plurality of solar modules 50a, 50b, ..., 50n through power line communication, and this 820).

The power line communication at this time is preferably a high-speed power line communication (PLC) system that is robust to noise. That is, each communication unit 570 in the plurality of solar modules 50a, 50b, ..., 50n, based on a communication speed of 1 Mbps or more and a bandwidth of 2 to 30 MHz, can output information to the system, and , The first communication unit (810 in FIG. 16) may receive corresponding information.

In addition, the first communication unit (810 of FIG. 16) may separate the carrier frequency signal from the received AC power source and extract corresponding information from the carrier frequency signal. The extracted information may be transmitted to the control unit 820 of FIG. 16.

The control unit (820 in FIG. 16) signals photovoltaic power information received from the first communication unit (810 in FIG. 16), current and voltage information of the power conversion module connected to the solar cell module, and status information on the system. You can handle it. In addition, the signal-processed information may be controlled to be stored in the memory 860.

The memory (860 of FIG. 16) stores photovoltaic power information received through the first communication unit (810 of FIG. 16), current and voltage information of the power conversion module connected to the solar cell module, and status information about the system. I can.

The memory (860 of FIG. 16) may store, in particular, solar power information received in real time, current and voltage information of the power conversion module, and status information about a system received in real time.

The control unit 820 of FIG. 16 may generate monitoring information that can be monitored using accumulated and stored solar power information, current and voltage information of the power conversion module, and the like for a predetermined time.

The monitoring information at this time may include at least one of solar power information, current and voltage information on input/output of the power conversion unit connected to the solar cell module, and status information on the system.

The control unit (820 in FIG. 16) controls to store such monitoring information in a memory (860 in FIG. 16), or controls such information to be displayed or output as sound through an output unit (840 in FIG. 16). I can.

Meanwhile, the controller (820 in FIG. 16) may control to transmit the monitoring information to another external device through the second communication unit (830 in FIG. 16). For example, monitoring information may be transmitted to an adjacent mobile terminal 600, or may be transmitted to the server 300 or to the mobile terminal 600 through the network 750.

Meanwhile, the power unit 850 may receive separate power from the outside. Thereby, even when AC power does not flow through the grid, information can be received from the plurality of solar modules 50a, 50b, ..., 50n, respectively. Alternatively, information is received based on DC power even when AC power is not output from a plurality of solar modules 50a, 50b, ..., 50n while AC power does not flow to the grid. You can do it. Therefore, information can be stably received.

Server 300 or mobile terminal 600, a plurality of solar modules (50a, 50b, ..., 50n) is installed, solar power information for a building or solar power information corresponding to each module , It may be received from the second communication unit (830 of FIG. 16) of the communication device 800. Accordingly, it is possible to easily identify solar power information for each building or module.

Meanwhile, the server 300 may be a power company server, a provider server that provides power information, or a server of Taeyang and module manufacturing companies.

FIG. 2 is a front view of a solar module according to an embodiment of the present invention, FIG. 3 is a rear view of the solar module of FIG. 2, and FIG. 4 is an exploded perspective view of the solar cell module of FIG. 2.

2 to 4, the solar module 50 according to the embodiment of the present invention includes a solar cell module 100 and a junction box 200 positioned on one surface of the solar cell module 100. . In addition, the solar module 50 may further include a heat dissipating member (not shown) disposed between the solar cell module 100 and the junction box 200.

First, the solar cell module 100 may include a plurality of solar cells 130. In addition, the first sealing material 120 and the second sealing material 150 located on the lower and upper surfaces of the plurality of solar cells 130, the rear substrate 110 and the second located on the lower surface of the first sealing material 120 A front substrate 160 positioned on the upper surface of the sealing material 150 may be further included.

First, the solar cell 130 is a semiconductor device that converts solar energy into electrical energy, and includes a silicon solar cell, a compound semiconductor solar cell, and a stacked solar cell. It may be a tandem solar cell, a dye-sensitized type, or a CdTe, CIGS type solar cell, or the like.

The solar cell 130 is formed as a light-receiving surface on which sunlight is incident and a rear surface opposite to the light-receiving surface. For example, the solar cell 130 includes a first conductivity type silicon substrate, a second conductivity type semiconductor layer formed on the silicon substrate and having a conductivity type opposite to the first conductivity type, and a second conductivity type semiconductor layer. An antireflection film including at least one opening exposing a partial surface of the second conductive semiconductor layer and formed on the second conductive semiconductor layer, and a front electrode contacting a partial surface of the second conductive semiconductor layer exposed through at least one opening e And, a rear electrode formed on the rear surface of the silicon substrate.

Each solar cell 130 may be electrically connected in series or in parallel or in series and parallel. Specifically, the plurality of solar cells 130 may be electrically connected by the ribbon 133. The ribbon 133 may be bonded to a front electrode formed on the light-receiving surface of the solar cell 130 and a rear electrode current collecting electrode formed on the rear surface of another adjacent solar cell 130.

In the drawing, the ribbon 133 is formed in two rows, and the solar cells 130 are connected in a line by the ribbon 133 to form the solar cell string 140. As a result, six strings 140a, 140b, 140c, 140d, 140e, and 140f are formed, and each string includes 10 solar cells. Unlike the drawings, various modifications are possible.

Meanwhile, each solar cell string may be electrically connected by a bus ribbon. FIG. 2 shows the first solar cell string 140a and the second solar cell string 140b, respectively, by the bus ribbons 145a, 145c, and 145e disposed under the solar cell module 100. The battery string 140c and the fourth solar cell string 140d are electrically connected to each other, and the fifth solar cell string 140e and the sixth solar cell string 140f are electrically connected. In addition, FIG. 2 shows the second solar cell string 140b and the third solar cell string 140c, respectively, by the bus ribbons 145b and 145d disposed on the solar cell module 100. The battery string 140d and the fifth solar cell string 140e are electrically connected to each other.

Meanwhile, the ribbon connected to the first string, the bus ribbon 145b and 145d, and the ribbon connected to the fourth string are electrically connected to the first to fourth conductive lines 135a, 135b, 135c, and 135d, respectively. , The first to fourth conductive lines 135a, 135b, 135c, and 135d are the bypass diodes (Da, Db, and Dc in FIG. 6) in the junction box 200 disposed on the rear surface of the solar cell module 100 Connected. In the drawings, the first to fourth conductive lines 135a, 135b, 135c, and 135d extend to the rear surface of the solar cell module 100 through an opening formed on the solar cell module 100.

On the other hand, it is preferable that the junction box 200 is disposed closer to an end of the solar cell module 100 from which a conductive line extends.

2 and 3, since the first to fourth conductive lines 135a, 135b, 135c, and 135d extend from the top of the solar cell module 100 to the rear surface of the solar cell module 100, the junction box 200 ) Is located at the top of the rear surface of the solar cell module 100. Accordingly, the length of the conductive line can be shortened, so that power loss can be reduced.

The rear substrate 110, as a back sheet, has waterproof, insulating, and UV-blocking functions, and may be a TPT (Tedlar/PET/Tedlar) type, but is not limited thereto. In addition, although the rear substrate 110 is shown in a rectangular shape in FIG. 4, it may be manufactured in various shapes such as a circular shape or a semi-circular shape according to an environment in which the solar cell module 100 is installed.

On the other hand, on the rear substrate 110, the first sealing material 120 may be attached to the same size as the rear substrate 110 and formed, and on the first sealing material 120, a plurality of solar cells 130 They can be located adjacent to each other to achieve.

The second sealing material 150 may be positioned on the solar cell 130 and bonded to the first sealing material 120 by lamination.

Here, the first sealing material 120 and the second sealing material 150 allow the elements of the solar cell to be chemically bonded. The first sealing material 120 and the second sealing material 150 may be various examples such as an ethylene vinyl acetate (EVA) film.

On the other hand, the front substrate 160 is positioned on the second sealing material 150 to transmit sunlight, and is preferably a tempered glass to protect the solar cell 130 from external impacts. In addition, in order to prevent reflection of sunlight and increase the transmittance of sunlight, it is more preferable to use a low iron tempered glass containing less iron.

The junction box 200 is attached on the rear surface of the solar cell module 100 and may convert power using DC power supplied from the solar cell module 100. Specifically, the junction box 200 may include a power conversion module 700 that converts DC power into AC power and outputs it.

The power conversion module 700 may include a bypass diode (Da, Db, Dc), a converter unit (530 in FIG. 6), and an inverter unit (540 in FIG. 6) on one circuit board. Such, the power conversion module 700 may be referred to as a micro inverter.

Meanwhile, in the junction box 200, in order to prevent moisture penetration of circuit elements, a coating for preventing moisture penetration may be performed inside the junction box using silicon or the like.

On the other hand, an opening (not shown) is formed in the junction box 200, so that the first to fourth conductive lines 135a, 135b, 135c, and 135d described above are connected to the bypass diodes (Da, Db, in Fig. 6) in the junction box. Dc) can be connected.

Meanwhile, an AC output cable 38 for outputting the converted AC power to the outside may be connected to one side of the junction box 200.

Meanwhile, the solar module 50 may include a frame 105 for fixing an outer portion of the solar cell module 10. On the other hand, it is preferable that the thickness of the junction box 200 is smaller than the thickness of the frame 105 so that the junction box 200 does not protrude from the rear surface.

5 is an example of a configuration of a bypass diode of the solar module of FIG. 2.

Referring to the drawings, the bypass diodes Da, Db, and Dc may be connected to the six solar cell strings 140a, 140b, 140c, 140d, 140e, and 140f. Specifically, the first bypass diode Da is connected between the first solar cell string and the first bus ribbon 145a, so that in the first solar cell string 140a or the second solar cell string 140b When the reverse voltage is generated, the first solar cell string 140a and the second solar cell string 140b are bypassed.

For example, when a voltage of approximately 0.6V generated in a normal solar cell is generated, the potential of the cathode electrode is approximately 12V (=0.6V*20) compared to the potential of the anode electrode of the first bypass diode Da. It becomes higher. That is, the first bypass diode Da performs a normal operation rather than a bypass.

On the other hand, in a solar cell of the first solar cell string 140a, when a hot spot occurs due to the occurrence of shading or adhesion of foreign substances, the voltage generated in one solar cell is approximately 0.6V A reverse voltage (approximately -15V) is generated, not the voltage of. Accordingly, the potential of the anode electrode of the first bypass diode Da is approximately 15V higher than that of the cathode electrode, and the first bypass diode Da performs a bypass operation. Accordingly, the voltage generated from the solar cells in the first solar cell string 140a and the second solar cell string 140b is not supplied to the junction box 200. In this way, when a reverse voltage occurs in some solar cells, by bypassing, it is possible to prevent destruction of the solar cell or the like. In addition, it is possible to supply the generated DC power except for the hotspot area.

Next, the second bypass diode Db is connected between the first bus ribbon 145a and the second bus ribbon 145b, and in the third solar cell string 140c or the fourth solar cell string 140d. When the reverse voltage is generated, the third solar cell string 140c and the fourth solar cell string 140d are bypassed.

Next, the third bypass diode Dc is connected between the first solar cell string and the first bus ribbon 145a, and is reversed from the first solar cell string 140a or the second solar cell string 140b. When voltage is generated, the first solar cell string and the second solar cell string are bypassed.

Meanwhile, unlike FIG. 5, it is possible to connect six bypass diodes corresponding to six solar cell strings, and various other modifications are possible.

6 is an example of a block diagram of a power conversion module inside the junction box of FIG. 2.

Referring to the drawings, the power conversion module 700 inside the junction box includes a bypass diode unit 510, a converter unit 530, a capacitor C1, an inverter unit 540, a control unit 550, and a communication unit ( 570) may be included.

The bypass diode unit 510 includes bypass diodes Dc, Db, and Da respectively disposed between the first to fourth conductive lines 135a, 135b, 135c, and 135d of the solar cell module 100. It can be provided. At this time, the number of bypass diodes is one or more, and it is preferable that one is smaller than the number of conductive lines.

Bypass diodes (Dc, Db, Da) from the solar cell module 50, in particular, from the first to fourth conductive lines (135a, 135b, 135c, 135d) in the solar cell module 50 Receive power. In addition, the bypass diodes Dc, Db, and Da can be bypassed when a reverse voltage is generated from DC power from at least one of the first to fourth conductive lines 135a, 135b, 135c, and 135d. have.

Meanwhile, the input power Vpv passed through the bypass diode unit 510 is input to the converter unit 530.

The converter unit 530 converts the input power Vpv output from the bypass diode unit 510. Meanwhile, the converter unit 530 may be referred to as a first power conversion unit.

For example, the converter unit 530 may convert the DC input power Vpv into a pseudo DC voltage, as shown in FIG. 8A. Accordingly, the pseudo DC power may be stored in the capacitor C1. Meanwhile, both ends of the dc terminal capacitor C1 may be referred to as a dc terminal, and the capacitor C1 may be referred to as a dc terminal capacitor.

As another example, the converter unit 530 may boost DC input power Vpv and convert it into DC power, as shown in FIG. 8A. Accordingly, the boosted DC power may be stored in the dc terminal capacitor C1.

The inverter unit 540 may convert DC power stored in the DC terminal capacitor C1 into AC power. Meanwhile, the inverter unit 540 may be referred to as a second power conversion unit.

For example, the inverter unit 540 may convert a pseudo DC voltage converted by the converter unit 530 into AC power.

As another example, the inverter unit 540 may convert the DC power boosted by the converter unit 530 into AC power.

Meanwhile, it is preferable that the converter unit 530 includes a plurality of interleaving converters to convert a pseudo DC voltage or convert a boosted voltage supply.

In particular, in the embodiment of the present invention, it is assumed that the converter unit 530 includes three or more interleaving converters.

In the drawing, n converters 610a, 610b, ... 610n are connected in parallel with each other. The energy conversion capacity of n converters 610a, 610b, ... 610n may be the same.

The current by the DC input power supply (Vpv) decreases to 1/N in n converters 610a, 610b,...610n, and at the output terminals of n converters 610a, 610b,...610n, The output current of each converter is summed into one.

On the other hand, n converters (610a, 610b, ... 610n), interleaving operation, the current phase of each of the n converters (610a, 610b, ... 610n) is + (360 ° / N) compared to the reference phase ), -(360°/N) or a phase delay close thereto.

In this way, when n converters are interleaved, the ripple of the input current and the output current of the converter unit 530 is reduced, and thus, the capacity and size of the circuit elements in the power conversion module 700 are reduced. There is an advantage. Accordingly, the thickness of the junction box may be smaller than the thickness of the frame 105 of the solar cell module.

Meanwhile, as the interleaving converter, a tap inductor converter or a flyback converter may be used.

Meanwhile, the AC power converted by the inverter unit 540 is added with predetermined information through the communication unit 570 and is output to the outside.

That is, the communication unit 570 adds a carrier frequency signal including predetermined information to the AC power converted by the inverter unit 530 by power line communication (PLC), and outputs the AC power including the information to the system. can do.

The information at this time includes power generation information of a photovoltaic module including a photovoltaic module, input of a photovoltaic module, output current information, input of a photovoltaic module, output voltage information, information about an operation state of a photovoltaic module, and a photovoltaic module. It may include at least one of the error information of. Such information may be generated by the controller 550.

Meanwhile, when the level of the converted AC power is less than or equal to a predetermined value, the communication unit 570 may add a carrier signal including information to the predetermined DC power and output the DC power including the information to the system.

For example, when the solar module cannot generate DC power and there is no converted AC power, the communication unit 570 adds a carrier signal including information to a separate DC power source, The power supply may be output to the system, or a DC power supply including information may be output to the system by adding a carrier signal including information to the 0 level DC power supply. Accordingly, even when the DC power is not generated or the level of the AC power is below a predetermined level, communication can be performed through a grid.

On the other hand, the communication unit 570 may perform one-way communication in the grid direction instead of two-way communication, and accordingly, the configuration of the power conversion module 700 can be simply configured.

On the other hand, the communication device 800 can each receive information from the plurality of solar modules 50a, 50b, ..., 50n through power line communication (PLC). That is, information may be received from a plurality of photovoltaic modules 50a, 50b, ..., 50n through a grid, and signal processing may be performed.

On the other hand, the power line communication is preferably a high-speed power line communication (PLC) system that is robust to noise. That is, each communication unit 570 in the plurality of photovoltaic modules 50a, 50b, ..., 50n can output information to the system based on a communication speed of 1 Mbps or more and a bandwidth of 2 to 30 MHz. .

7A is an example of an internal circuit diagram of the power conversion module of FIG. 6.

Referring to the drawings, the power conversion module 700, a bypass diode unit 510, a converter unit 530, a dc terminal capacitor (C1), an inverter unit 540, a control unit 550, a filter unit 560 , And a communication unit 570 may be included.

7A illustrates a tap inductor converter as an interleaving converter. In the drawing, it is exemplified that the converter unit 530 includes first to third tap inductor converters 611a, 611b, ... 611c.

The bypass diode unit 510 includes first to fourth conductive lines 135a, 135b, 135c, and 135d disposed between the nodes a, b, c, and d respectively corresponding to the first to fourth conductive lines 135a, 135b, 135c, and 135d. It includes a third bypass diode (Da, Db, Dc).

The converter unit 530 may perform power conversion by using the DC power Vpv output from the bypass diode unit 510.

In particular, the first to third tap inductor converters 611a, 611b, ... 611c output the converted DC power to the dc terminal capacitor C1 by interleaving operation.

Among them, the first tapped inductor converter 611a is a tapped inductor T1, a switching element S1 connected between the tapped inductor T1 and the ground terminal, and a diode connected to the output terminal of the tapped inductor to perform one-way conduction. (D1) is included. Meanwhile, between the output terminal of the diode D1, that is, the cathode and the ground terminal, a dc terminal capacitor C1 is connected.

Specifically, the switching element S1 may be connected between the tap and the ground terminal of the tap inductor T. In addition, the output terminal (secondary side) of the tapped inductor T is connected to the anode of the diode D1, and the dc terminal capacitor C1 is connected between the cathode and the ground terminal of the diode D1. do.

Meanwhile, the primary side and the secondary side of the tapped inductor T have opposite polarities. Meanwhile, the tap inductor T may be referred to as a switching transformer.

Meanwhile, the primary side and the secondary side of the tapped inductor T are connected to each other as shown in the figure. Accordingly, the tapped inductor converter may be a non-insulated type converter.

On the other hand, when three tap inductor converters 611a, 611b, and 611c are connected in parallel to each other and driven in an interleaving method as shown in the figure, since input current components are branched in parallel, each tap inductor converter 611a, The ripple of the current component output through 611b and 611c is reduced.

Meanwhile, each of the tapped inductor converters 611a, 611b, and 611c can operate adaptively in response to the power required value of the output AC power source.

For example, when the power requirement is approximately 90W to 130W, only the first converter 611a operates, or when the power requirement is approximately 190W to 230W, only the first and second converters 611a and 611b operate, or When the required value is approximately 290W to 330W, all of the first to third interleaving converters 611a, 611b, and 611c can operate. That is, each tap inductor converter 611a, 611b, and 611c may selectively operate. Such an optional operation may be controlled by the controller 550.

The inverter unit 540 converts the DC power level converted by the converter unit 530 into AC power. In the drawing, a full-bridge inverter is illustrated. That is, the upper and lower arm switching elements (Sa, Sb) and lower arm switching elements (S'a, S'b) that are connected in series with each other become a pair, and a total of two pairs of upper and lower arm switching elements are parallel to each other (Sa&S'a, It is connected to Sb&S'b). Diodes are connected in reverse parallel to each of the switching elements Sa, S'a, Sb, S'b.

The switching elements in the inverter unit 540 are turned on/off based on the inverter switching control signal from the controller 550. As a result, an AC power source having a predetermined frequency is output. Preferably, it is desirable to have the same frequency (about 60Hz or 50Hz) as the alternating current frequency of the grid.

The filter unit 560 performs lowpass filtering, understanding smoothing the AC power output from the inverter unit 540. To this end, in the drawings, inductors Lf1 and Lf2 are illustrated, but various examples are possible.

Meanwhile, after the filter unit 560, a communication unit 570 for power line communication with the system may be disposed.

The communication unit 570 may add predetermined information to an AC power source with reduced noise by using a carrier signal of a predetermined frequency. That is, power line communication can be performed. Then, the communication unit 570 outputs the AC power to which information is added to a grid.

On the other hand, the converter input current detection unit (A) detects the input current (ic1) input to the converter unit 530, the converter input voltage detection unit (B), the input voltage input to the converter unit 530 ( vc1) is detected. The sensed input current ic1 and input voltage vc1 may be input to the controller 550.

On the other hand, the converter output current detection unit (C) detects the output current (ic2) output from the converter unit 530, that is, the dc end current, and the converter output voltage detection unit (D) is, in the converter unit 530 It senses the output voltage (vc2), that is, the dc voltage. The sensed output current ic2 and output voltage vc2 may be input to the controller 550.

On the other hand, the inverter output current detection unit (E) detects the current (ic3) output from the inverter unit 540, the inverter output voltage detection unit (F), the voltage (vc3) output from the inverter unit 540 Is detected. The sensed current ic3 and voltage vc3 are input to the controller 550.

Meanwhile, the control unit 550 may output a control signal for controlling the switching element S1 of the converter unit 530 of FIG. 7. In particular, the control unit 550 is applied to at least one of the sensed input current (ic1), input voltage (vc1), output current (ic2), output voltage (vc2), output current (ic3), or output voltage (vc3). Based on this, a turn-on timing signal of the switching element S1 in the converter unit 530 may be output.

Meanwhile, the control unit 550 may output an inverter control signal that controls each of the switching elements Sa, S'a, Sb, and S'b of the inverter unit 540. In particular, the control unit 550 is applied to at least one of the sensed input current (ic1), input voltage (vc1), output current (ic2), output voltage (vc2), output current (ic3), or output voltage (vc3). Based on this, the turn-on timing signal of each of the switching elements Sa, S'a, Sb, S'b of the inverter unit 540 may be output.

Meanwhile, the control unit 550 may control the converter unit 530 to calculate a maximum power point for the solar cell module 100 and output DC power corresponding to the maximum power accordingly.

On the other hand, the control unit 550, the power generation information of the solar module, input of the solar module, output current information, input of the solar module, output voltage information, operation state information of the solar module, error information of the solar module At least one of can be created.

In addition, the communication unit 570 includes information by adding a carrier frequency signal including information generated by the control unit 550 to the AC power converted by the inverter unit 530 by high-speed power line communication (PLC). AC power can be output to the system.

Meanwhile, when the level of the converted AC power is less than or equal to a predetermined value, the communication unit 570 may add a carrier signal including information to the predetermined DC power and output the DC power including the information to the system.

7B is another example of an internal circuit diagram of the power conversion module of FIG. 6.

The power conversion module 700 of FIG. 7B is the same as the power conversion module 700 of FIG. 7A, a bypass diode part 510, a converter part 530, a dc terminal capacitor C1, and an inverter part 540. , A control unit 550, a filter unit 560, and a communication unit 570 may be included.

However, FIG. 7B illustrates a flyback converter as an interleaving converter in the converter unit 530. In the drawing, it is illustrated that the converter unit 530 includes a first flyback converter to a third flyback converter 612a, 612b, ... 612c.

In particular, the first flyback converter to the third flyback converter 612a, 612b, ... 612c, unlike the non-insulated type tap inductor converter, is an isolated type, and each converted DC power supply by interleaving operation Output to dc terminal capacitor (C1).

Among these, the first flyback converter 612a is connected to the transformer (T11), the switching element (S11) connected between the primary side and the ground terminal of the transformer (T11), and the secondary side of the transformer (T11) to conduct one-way conduction. It includes a diode (D11) to perform. Meanwhile, between the output terminal of the diode D11, that is, the cathode and the ground terminal, the dc terminal capacitor C1 is connected. On the other hand, the primary side and the secondary side of the transformer T11 have opposite polarities.

On the other hand, the control unit 550, the power generation information of the solar module, input of the solar module, output current information, input of the solar module, output voltage information, operation state information of the solar module, error information of the solar module At least one of can be created.

In addition, the communication unit 570 includes information by adding a carrier frequency signal including information generated by the control unit 550 to the AC power converted by the inverter unit 530 by high-speed power line communication (PLC). AC power can be output to the system.

Meanwhile, when the level of the converted AC power is less than or equal to a predetermined value, the communication unit 570 may add a carrier signal including information to the predetermined DC power and output the DC power including the information to the system.

8A and 8B are views illustrating a method of operating the power conversion module of FIG. 6.

First, referring to FIG. 8A, the converter unit 530 of the power conversion module 700 according to an embodiment of the present invention converts DC power from the solar cell module 100 into a pseudo DC voltage. Can be converted.

As shown in FIG. 7A, when the converter unit 530 is a tap inductor converter or the converter unit 530 is a flyback converter as shown in FIG. 7B, full-wave rectification is performed by switching on/off of the switching element S1 or S11. It can be converted into a pseudo DC voltage, which has the same envelope as the DC power supply. Accordingly, the pseudo DC power may be stored in the capacitor C1.

Meanwhile, the inverter 540 receives a pseudo DC voltage, performs a switching operation, and outputs it as AC power. Specifically, a pseudo DC voltage having the same envelope as the full-wave rectified DC power source may be used, and converted into an AC power source having + and-and output. In particular, it can be converted into an AC power source corresponding to the system frequency and output.

Next, referring to FIG. 8B, the converter unit 530 of the power conversion module 700 according to an embodiment of the present invention converts the DC power from the solar cell module 100 to a level and specifically boosts, It can be converted to a boosted DC power supply.

7A, when the converter unit 530 is a tap inductor converter or the converter unit 530 is a flyback converter, as shown in FIG. 7B, by switching on/off of the switching element S1 or S11, the DC power supply ( Vp) can be converted into a boosted DC power supply. Accordingly, the boosted DC power may be stored in the capacitor C1.

The inverter 540 receives the boosted DC power, performs a switching operation, and outputs the AC power. In particular, it can be converted into an AC power source corresponding to the system frequency and output.

9A to 9B are views referenced for explaining the operation of the tapped inductor converter of FIG. 7A.

Briefly describing the operation of the first tapped inductor converter 611a, when the switching element S1 is turned on, as shown in FIG. 9A, the input voltage Vpv, the primary side of the tapped inductor T1, and A closed loop is formed through the switching element S1, and the first current I1 flows on the closed loop. At this time, since the secondary side of the tapped inductor T1 has a polarity opposite to that of the primary side, the diode D1 cannot conduct and is turned off. Accordingly, energy by the input voltage Ppv is stored in the primary side of the tapped inductor T1.

Next, when the switching element S1 is turned off, as shown in FIG. 9B, the input voltage Vpv, the primary side and the secondary side of the tapped inductor T1, and the diode D1, and the capacitor C1 Through the closed loop (closed loop) is formed, the second current (I2) flows on the closed loop. That is, since the secondary side of the tapped inductor T1 has a polarity opposite to that of the primary side, the diode D1 becomes conductive. Accordingly, the input voltage Ppv and energy stored in the primary and secondary sides of the tapped inductor T1 may be stored in the capacitor C1 through the diode D1.

In this way, the converter unit 530 can output a pseudo DC power supply or a high-efficiency high-voltage DC power supply by using the input voltage Ppv and the energy stored in the primary side and the secondary side of the tapped inductor T1. .

10A and 10B are diagrams referenced for explaining that the converter of FIG. 6 outputs a pseudo DC power using an input power source.

6 and 10A, the first to third interleaving converters 610a, 610b, and 610c in the converter unit 530 output a pseudo DC power by using an input power Vpv that is DC.

Specifically, the converter unit 530 outputs a pseudo DC power having a peak value of approximately 330V using a DC power supply of approximately 32V to 36V from the solar cell module 100.

To this end, the controller 550 determines the duty of the switching elements of the first to third interleaving converters 610a, 610b, and 610c, based on the detected input power (Vpv) and the detected output power (Vdc). Decide.

In particular, the lower the input voltage Vpv, the greater the duty of the switching element of the first to third interleaving converters 610a, 610b, and 610c, and the higher the input voltage Vpv, the smaller the duty of the switching element. .

On the other hand, as the target output power Vdc is lower, the duty of the switching elements of the first to third interleaving converters 610a, 610b and 610c decreases, and as the target output power Vdc is higher, the duty of the switching elements Becomes larger. For example, when the target output power Vdc has a peak value of approximately 330V, the duty of the switching element may be the greatest.

In Fig. 10A, the pseudo DC power supply waveform Vslv outputted by the duty variable is illustrated, and the pseudo DC power supply waveform follows the target sine wave Vsin.

On the other hand, in the present invention, it is assumed that the switching frequency of the converter unit 530 is varied so that the pseudo DC power supply waveform Vslo more accurately follows the full-wave rectified waveform Vsin.

As shown in FIG. 10B, when the switching frequency of the converter unit 530 is fixed, the error ΔE2 between the pseudo DC power waveform Vslf and the target sine wave Vsin is the converter unit 530 of FIG. 10A When the switching frequency of is varied, it becomes larger than the error ΔE1 between the pseudo DC power supply waveform Vslv and the target sinusoidal waveform Vsin.

In the present invention, in order to reduce such an error, the switching frequency of the converter unit 530 is varied. That is, the switching frequency of the switching elements of the first to third interleaving converters 610a, 610b, and 610c is varied.

The control unit 550 sets the switching frequency of the converter unit 530 to increase as the rate of change of the target sine wave Vsin increases, that is, the switching period decreases, and the rate of change of the target sine wave Vsin decreases. As the value increases, the switching frequency of the converter unit 530 may be reduced, that is, the switching period may be increased.

In Fig. 10A, it is exemplified that the switching period is set to Ta in the rising section of the target sine wave (Vsin), and the switching period is set to be Tb, which is greater than Ta, in the peak section of the target sine wave (Vsin). . That is, the switching frequency corresponding to the switching period Ta is higher than the switching frequency corresponding to the switching period Tb. Thereby, the error ΔE1 between the pseudo DC power supply waveform Vslv and the target sine waveform Vsin can be reduced.

Meanwhile, it is also possible to describe the switching frequency variation of FIG. 10A as a switching mode technique of the switching element. For this, refer to FIGS. 11 to 12.

11 to 12 are diagrams referenced for explaining a switching frequency variation according to a switching mode of a switching element.

First, (a) of FIG. 11 illustrates an example of a duty waveform diagram of a switching element of an interleaving converter. Referring to the drawing, in a first switching period (Tf1), during a first duty (duty1), the switching element is turned on, then turned off, in a second switching period (Tf2), during a second duty (duty2). The switching element is turned on and then turned off. In the drawing, it is illustrated that the first duty (duty1) is greater than the second duty (duty2).

Meanwhile, FIG. 11A illustrates that the switching period of the interleaving converter is fixed, and a discontinuous conduction mode (DCM) is applied as the switching mode.

When the switching period of the interleaving converter is fixed and dcm is applied as the switching mode, a current waveform Idcm flowing through the switching element as shown in (b) of FIG. 11 may be illustrated. As the switching element is turned on, the current flowing through the switching element increases, and as the switching element is turned off, the current decreases.

FIG. 11C illustrates an actual current waveform flowing through the switching element of the interleaving converter according to dcm, and FIG. 11D illustrates the switching voltage across the switching elements of the interleaving converter according to dcm.

Meanwhile, after the switching element is turned off, before the next switching period is performed, a resonance period 1105 in the interleaving converter may occur. At this time, when the switching element is operated by dcm, a period 1107 in which the switching voltage across the switching element does not become zero occurs. Accordingly, zero voltage switching (ZVS) for the switching element is not performed, and the efficiency of the interleaving converter is degraded.

In the present invention, in order to solve this problem, a CRM (critical conduction mode) mode is used as a switching mode instead of dcm. CRM may also be referred to as BCM (boundary conduction mode) mode or TM (transition mode) mode.

CRM refers to a mode in which a switching cycle starts whenever the current flowing through the switching element becomes zero after the switching element of the interleaving converter is turned off. Accordingly, in the CRM, the switching period may be varied according to the duty of the switching period.

12A illustrates an example of a duty waveform diagram of a switching element of an interleaving converter. Referring to the drawing, the switching element is turned on during a first duty1, within a first switching period Tfa, and then turned off, and during a second duty2, within a second switching period Tfb. The switching element is turned on and then turned off. In the drawing, it is illustrated that the first duty (duty1) is greater than the second duty (duty2).

Meanwhile, FIG. 12A illustrates that a CRM in which a switching frequency is variable is applied as a switching mode as a switching period of an interleaving converter is varied according to a change in duty.

As the switching mode, when CRM having a variable switching frequency is applied, a current waveform Icrm flowing through the switching element as shown in FIG. 12B may be illustrated. As the switching element is turned on, the current flowing through the switching element increases, and as the switching element is turned off, the current decreases. And, when the current flowing through the switching element becomes zero, that is, zero crossing, a new switching cycle starts.

FIG. 12C illustrates an actual current waveform flowing through the switching element of the interleaving converter according to crm, and FIG. 12D illustrates the switching voltage across the switching elements of the interleaving converter according to crm.

Meanwhile, after the switching element is turned off, a resonance period 1105 in the interleaving converter may occur. At this time, if the switching element is operated by crm, the time point at which the current of the switching element becomes zero is determined, that is, when the current becomes zero, even though the resonance section 1105 occurs, the switching element is turned on. Can be turned on. In other words, a new switching cycle may begin. Accordingly, zero voltage switching (ZVS) can be performed for the switching element, and the efficiency of the interleaving converter is improved.

Accordingly, in the present invention, the switching frequency of the switching element of the interleaving converter is varied based on crm.

Meanwhile, as shown in FIG. 6, when three interleaving converters 610a, 610b, and 610c are used, the first to third interleaving converters 610a, 610b, and 610c operate with a phase difference, respectively.

At this time, in a state in which the switching frequency variable is applied, for the operation period of the first to third interleaving converters 610a, 610b, and 610c, when a constant phase difference, for example, 120° is set, the switching period becomes longer. In this case, there may be a problem in that the output power is lowered. This will be described with reference to FIGS. 14 and 15.

13 illustrates a case in which switching frequencies are fixed in three interleaving converters 610a, 610b, and 610c.

Referring to the drawing, the switching periods of the three interleaving converters 610a, 610b, and 610c are the same as Period A, Period B, and Period C, respectively, and the difference between the operation periods of the three interleaving converters 610a, 610b, and 610c. It can be seen that the phase difference is a constant interval.

In addition, the operation period of the three interleaving converters 610a, 610b, and 610c is a partial period (ΔDuty A, ΔDuty B, ΔDuty C) within each switching period, and the operation period of the three interleaving converters 610a, 610b, 610c May be initiated by a PWM interrupt signal.

At this time, in the operation section of the three interleaving converters 610a, 610b, and 610c, if all of the duties are the same, as shown in the figure, the average power of the three interleaving converters 610a, 610b, and 610c is the same. do.

That is, when the switching frequencies of the three interleaving converters 610a, 610b, and 610c are fixed and the phase difference is fixed, there is an advantage that the average power of the three interleaving converters 610a, 610b and 610c is approximately constant.

However, when the phase difference is fixed while the switching frequency is varied, there is a problem that the output power is momentarily lowered. This will be described with reference to FIG. 14.

14 illustrates a case in which a switching frequency is variable and a phase difference is fixed in three interleaving converters 610a, 610b, and 610c.

Referring to the drawing, it can be seen that the switching period from 0 to 9Tv is fixed at 3Tv, and the phase difference between the phases (phase a, phase b, and phase c) of the three interleaving converters 610a, 610b, and 610c is Tv. have.

At the next time point 9Tv, it is illustrated that the switching period is variable and the switching period increases three times to 9Tv. In this case, the first interleaving converter operates during the 3TV period after 3Tv compared to the previous switching period, but the second interleaving converter considers the variable duty (3Tv) of the first interleaving converter, compared to the previous switching period, After 5Tv, it operates during the 3TV period. The third interleaving converter also operates during the 3TV period after 7Tv compared to the previous switching period in consideration of the variable duty (3Tv) of the second interleaving converter.

At this time, the phase difference between the first to third interleaving converters is fixed at 120 degrees, respectively, despite the variable switching period. That is, after the first interleaving converter operates, the second interleaving converter and the third interleaving converter operate after the 3TV period and after the 6TV period, respectively.

In the switching period variable periods 1310 and 1320, power output by the second interleaving converter and the third interleaving converter decreases compared to the first interleaving converter. Therefore, the output current or output voltage of the converter unit 530 is momentarily lowered.

In order to solve this point, in an embodiment of the present invention, in a plurality of interleaving converters, when a switching period is varied, in order to resolve output imbalance between the interleaving converters, the phases of the operation periods of the plurality of interleaving converters are varied. This will be described with reference to FIG. 15.

15 illustrates a case in which the switching frequency and the phase difference are varied in three interleaving converters 610a, 610b, and 610c.

Referring to the drawing, it can be seen that the switching period from 0 to 9Tv is fixed at 3Tv, and the phase difference between the phases (phase a, phase b, and phase c) of the three interleaving converters 610a, 610b, and 610c is Tv. have.

Next, at the time point 9Tv, the switching period is variable, so that the switching period increases three times to 9Tv. In this case, the first interleaving converter operates during the 3TV period after 3Tv compared to the previous switching period, and in the switching period variable period 1410, the second interleaving converter is 3Tv after the switching period variable time of 9Tv, The third interleaving converter operates during the 3TV period, and the third interleaving converter may operate during the 3TV period after 6Tv from 9Tv as the switching period variable time point.

That is, unlike FIG. 14, the control unit 550 varies the phase difference between the first to third interleaving converters in response to a variable period. According to the drawing, the phase difference between the first interleaving converter and the second interleaving converter and the phase difference between the second interleaving converter and the third interleaving converter are varied from 120 degrees to 40 degrees.

When the switching period is increased, the controller 550 may change the phase so that the phase difference between the interleaving converters is reduced. Similarly, when the switching period is reduced, the phase may be changed so that the phase difference between each interleaving converter increases, for example, from 120 degrees to 130 degrees, or the like.

On the other hand, when the switching period is increased, the controller 550 may change the phase so that a region in which the phases of the operation periods between the interleaving converters are overlapped is generated, in particular, is increased. In the drawing, an operation period between the first interleaving converter and the second interleaving converter is overlapped during a 2TV period.

On the other hand, after the switching period is variable, at a time point 18Tv, the first interleaving converter operates during the 3TV period compared to the previous switching period, after 9Tv, but the second interleaving converter operates during the 3TV period, compared to the previous switching period, and after 9.1Tv, the 3TV period During operation, the third interleaving converter can also operate during the 3TV period after 9.1Tv compared to the previous switching period.

After the variable period, the control unit 550 may sequentially change the phase difference so that the phase difference within each converter approaches the reference phase difference. According to the drawing, it can be seen that after the time point 18Tv, the phase difference between the first interleaving converter and the second interleaving converter, and the phase difference between the second interleaving converter and the third interleaving converter increase from 40 degrees to approximately 41 degrees. have.

In this way, by sequentially bringing the phase difference closer to the original reference phase difference of 120 degrees, current distortion can be prevented, and the above-described output deterioration of the second and third interleaving converters can also be prevented. .

On the other hand, this phase variation is applicable when at least two interleaving converters are performed. For example, even when two interleaving converters are used, the phase may be varied.

On the other hand, in Figs. 10A to 15, the switching frequency variable and the phase variable are applicable to the converter unit 530, and in particular, as shown in Fig. 7A, the converter unit 530 is a tap inductor converter, or Likewise, it is applicable when the converter unit 530 is a flyback converter.

16 is an example of an internal block diagram of the communication device of FIG. 1.

Referring to the drawings, the communication device 800 can receive information on a plurality of solar modules 50a, 50b, ..., 50n from a system through high-speed power line communication. Such a communication device 800 may also be referred to as a gateway.

To this end, the communication device 800 may include a first communication unit 810, a control unit 820, a second communication unit 830, an output unit 840, a power supply unit 850, and a memory 860. .

The first communication unit 810 may receive information from each of the plurality of solar modules 50a, 50b, ..., 50n through power line communication, and transmit the information to the control unit 820.

The received information is solar power information from a plurality of solar cell modules (100a, 1000b, ..., 100n) or a plurality of solar modules (50a, 50b, ..., 50n), connected to the solar cell module Input/output current and voltage information in the power conversion module 700, error information of each solar cell module (100a, 1000b, ..., 100n) or each solar module (50a, 50b, ..., 50n) , System operation status information, etc.

Here, the solar power information may be information on a solar cell module or real-time power generation amount generated by the solar module.

The power line communication at this time is preferably a high-speed power line communication (PLC) system that is robust to noise. That is, the first communication unit 810, based on a communication speed of 1 Mbps or more and a bandwidth of 2 to 30 MHz, the information of the plurality of solar modules 50a, 50b, ..., 50n, from the grid Can receive.

Further, the first communication unit 810 may separate the carrier frequency signal from the received AC power and extract corresponding information from the carrier frequency signal. In particular, the first communication unit 810 may extract the added solar power information using an orthogonal frequency division modulation method (OFDM). The extracted information may be transmitted to the control unit 820.

On the other hand, the first communication unit 810, when a problem occurs in the system, and the communication unit 572 of the power conversion module 700 adds information to the DC power and transmits it, the solar power information is added from the system. It can also receive the DC power.

The controller 820 may signal-process solar power information received from the first communication unit 810, current and voltage information of a power conversion module connected to the solar cell module, and status information about a system. In addition, the signal-processed information may be controlled to be stored in the memory 860.

The memory 860 may store photovoltaic power information received through the first communication unit 810, current and voltage information of a power conversion module connected to the solar cell module, and state information about a system.

In particular, the memory 860 may store photovoltaic power information received in real time, current and voltage information of the power conversion module, and state information about a system received in real time.

The controller 820 may generate monitoring information that can be monitored by using accumulated and stored solar power information, current and voltage information of the power conversion module, and the like for a predetermined time.

The monitoring information at this time may include at least one of solar power information, current and voltage information on input/output of the power conversion module connected to the solar cell module, and status information on the system for a predetermined period. .

Meanwhile, the controller 820 may control such monitoring information to be stored in the memory 860 or to display the corresponding information or to be output as sound through the output unit 840.

Meanwhile, the controller 820 may control to transmit the monitoring information to another external device through the second communication unit 830. For example, monitoring information may be transmitted to an adjacent mobile terminal 600, or may be transmitted to the server 300 or to the mobile terminal 600 through the network 750.

The second communication unit 830 may add monitoring information to the wireless signal and output it. For example, monitoring information may be transmitted to the mobile terminal 800, a router, etc., which are wirelessly connected by Wi-Fi, Bluetooth, NFC, and Zigbee communication methods.

Meanwhile, the second communication unit 830 may add and output monitoring information to a wired signal. For example, it is possible to transmit monitoring information to a router, a PC, a meter, a data logger, a monitoring device 880, etc., which are connected by wire through an Ethernet or RS485 communication method.

The second communication unit 830 may be connected to the server 300 or the mobile terminal 600 through a network or directly. The second communication unit 830 provides solar power information for a building or solar power information corresponding to each module in which a plurality of solar modules 50a, 50b, ..., 50n are installed, and the server 300 ) Or to the mobile terminal 600. Accordingly, it is possible to easily grasp the generated solar power information for each building or module.

Meanwhile, the output unit 840 may include a display such as LED, LCD, or OLED, and an audio output unit such as a speaker. Monitoring information generated by the control unit 820 may be output through a display of the output unit 840 or an audio output unit.

Meanwhile, the power unit 850 may receive separate power from the outside. As a result, unlike a conventional communication device that operates on a grid based on AC power, the communication device 800 is operable even when the AC power does not flow through the system.

Furthermore, even when AC power does not flow through the system, information can be received from the plurality of photovoltaic modules 50a, 50b, ..., 50n, respectively, through the first communication unit 810. Alternatively, even when AC power is not output from the plurality of solar modules 50a, 50b, ..., 50n while AC power does not flow to the grid, through the first communication unit 810, Information can be received based on the DC power supply. Therefore, information can be stably received.

17A to 17C illustrate various examples of a communication method between the solar module of FIG. 1 and a communication device.

First, FIG. 17A illustrates a power line communication method when AC power is output from the power conversion device 700.

The communication unit 570 in the power conversion device 700 adds a carrier frequency signal 1715 including predetermined information to the AC power supply 1710 output from the inverter unit 530. Accordingly, the AC power 1718 to which the carrier frequency signal has been added is output to the system, and the communication device 800 may receive the corresponding AC power and extract information.

Next, FIG. 17B illustrates an example of a power line communication method when AC power is output from the power conversion device 700.

When there is no AC power output from the inverter unit 530, the communication unit 570 in the power conversion device 700 transmits a carrier frequency signal 1715 including predetermined information to the DC power supply 1720 of the first level. Add. Accordingly, the AC power 1728 to which the carrier frequency signal is added is output to the system, and the communication device 800 receives the AC power 1728 and extracts information.

Next, FIG. 17C illustrates another example of a power line communication method when AC power is output from the power conversion device 700.

When there is no AC power output from the inverter unit 530, the communication unit 570 in the power conversion device 700 adds a carrier frequency signal 1715 including predetermined information to the DC power supply 1730 of the 0 level. do. That is, only the carrier frequency signal 1715 including predetermined information is outputted to the system, and the communication device 800 may receive the carrier frequency signal 1715 and extract information.

Meanwhile, the high-speed power line communication technique in the power conversion apparatus 700 described above is applicable to the case of the power conversion module 701 or 702 in FIGS. 18 to 21B below.

On the other hand, in the power conversion device 700 described above, a technique of varying the phase difference while varying the switching periods of the plurality of interleaving converters, in addition to the solar system 10 of FIG. 1, the following FIGS. 18 to 21B. It is applicable to the same case as the power conversion module 701 or 702 in.

18 is an example of a configuration diagram of a solar system according to another embodiment of the present invention.

Referring to the drawings, the solar system 20 of FIG. 18 exchanges data through a communication device 800, a communication device 800 and a network 750, similar to the solar system 10 of FIG. 1 A server 300, a communication device 800, or a mobile terminal 600 capable of exchanging data with the server 300 may be provided.

Meanwhile, the solar system 20 of FIG. 18 is similar to the solar system 10 of FIG. 1, but the junction box 201 has only a bypass diode, and the solar modules 50a, 50b, ... There is a difference in that the separate power conversion modules 701a, 701b, ..., 701n separated from 50n) have a converter unit, a control unit, an inverter unit, and a communication unit (761 in Fig. 19A or 19B). .

That is, each solar module (50a, 50b, ..., 50n), each solar cell module (100a, 1000b, ..., 100n), and each solar cell module (100a, 100b, ..., 100n) ), and has a junction box (201a, 201b, ..., 201n) that outputs DC power from each solar cell module (100a, 1000b, ..., 100n) through a bypass diode. I can.

In addition, separate power conversion modules (701a, 701b, ..., 701n) are electrically connected to the output terminals of each of the junction boxes (201a, 201b, ..., 201n), and convert the input DC power to , Can be converted to AC power and output.

Separate power conversion modules 701a, 701b, ..., 701n may be connected in parallel to each other to supply AC power generated by a grid (grid).

19A is an example of an internal circuit diagram of the power conversion module of FIG. 18, and FIG. 19B is another example of an internal circuit diagram of the power conversion module of FIG. 18.

Referring to the drawings, the power conversion module 701 of FIG. 19A is similar to the power conversion module 700 of FIG. 7A, but the difference is that the bypass diode unit 510 is not provided.

Accordingly, the power conversion module 701 may include a converter unit 530, a dc terminal capacitor C1, an inverter unit 540, a control unit 550, a filter unit 560, and a communication unit 751. have. Meanwhile, the converter unit 530 may include a tapped inductor converter as an interleaving converter.

The power conversion module 701 of FIG. 19B is similar to the power conversion module 700 of FIG. 7B, except that the bypass diode unit 510 is not provided. Meanwhile, the converter unit 530 of FIG. 19B is an interleaving converter and may include a flyback converter.

On the other hand, the communication unit 571 can add predetermined information to an AC power source with reduced noise by using a carrier signal of a predetermined frequency. That is, power line communication can be performed. Then, the communication unit 571 outputs the AC power to which the information has been added to a grid.

20 is an example of a configuration diagram of a solar system according to another embodiment of the present invention.

Referring to the drawings, the solar system 30 of FIG. 20 exchanges data through a communication device 800, a communication device 800 and a network 750, similar to the solar system 10 of FIG. 1 A server 300, a communication device 800, or a mobile terminal 600 capable of exchanging data with the server 300 may be provided.

On the other hand, the solar system 30 of FIG. 20 is similar to the solar system 10 of FIG. 1, but the junction box 201 includes a bypass diode, a converter unit, a control unit, etc., and an inverter unit and a communication unit There is a difference between not having That is, the inverter unit and the communication unit are provided in a separate power conversion module 1210, and the power conversion module 1210 is separated from the solar modules 100a, 100b, ..., 100n. have.

That is, each solar module (50a, 50b, ..., 50n), each solar cell module (100a, 1000b, ..., 100n), and each solar cell module (100a, 1000b, ..., 100n) ), which is attached to the back of each solar cell module (100a, 1000b, ..., 100n) and converts the direct current power from each solar cell module (100a, 1000b, ..., 100n) to output the converted direct current power (202a, 202b, ..., 202n) may be provided. The DC power output at this time may be a pseudo DC power or a boosted DC power.

In addition, a separate power conversion module 1210 is electrically connected to the output terminals of each of the junction boxes 202a, 202b, ..., 202n, converts the input DC power, converts it into AC power, and outputs it. In particular, by adding predetermined information to the carrier frequency signal, it is possible to output an AC power source to which the source information is added.

In addition, a separate power conversion module 1210 may supply AC power to which predetermined information is added to a system (grid).

21A is an example of an internal circuit diagram of the first and second power conversion modules of FIG. 20, and FIG. 21B is another example of an internal circuit diagram of the first and second power conversion modules of FIG. 20.

Referring to the drawings, the first power conversion module 702 of FIG. 21A may include a bypass diode unit 510, a converter unit 530, a dc terminal capacitor C1, and a converter control unit 551, The separate second power conversion module 1210 may include an inverter unit 540, an inverter control unit 552, a filter unit 560, and a communication unit 572.

The converter unit 530 is an interleaving converter and may include a tapped inductor converter.

The power conversion module 702 of FIG. 21B may include a bypass diode unit 510, a converter unit 530, a dc terminal capacitor C1, and a converter control unit 551, and a separate second power conversion module 1210 may include an inverter unit 540, an inverter control unit 552, a filter unit 560, and a communication unit 572. Meanwhile, the converter unit 530 of FIG. 21B is an interleaving converter and may include a flyback converter.

On the other hand, the communication unit 572 can add predetermined information to an AC power source with reduced noise by using a carrier signal of a predetermined frequency. That is, power line communication can be performed. Then, the communication unit 572 outputs the AC power to which the information has been added to a grid.

The communication device and the solar system according to the present invention are not limited to the configuration and method of the embodiments described as described above, but the embodiments are all or part of each embodiment so that various modifications can be made. It may be configured in combination selectively.

In addition, although the preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the specific embodiments described above, and the technical field to which the present invention belongs without departing from the gist of the present invention claimed in the claims. In addition, various modifications are possible by those of ordinary skill in the art, and these modifications should not be individually understood from the technical spirit or prospect of the present invention.

Claims (20)

delete delete delete delete delete delete delete delete A solar cell module including a plurality of solar cells; And
A power conversion module for converting and outputting power from DC power supplied from the solar cell module to AC power; And
A first communication unit for receiving AC power to which solar power information is added through the system, and a memory for storing the solar power information, current and voltage information of the power conversion module, and state information on the system, A communication device including a second communication unit for outputting monitoring information including at least one of the solar power information, the current and voltage information, and status information on the system to the outside; and
The power conversion module,
At least one bypass diode receiving the DC power from the solar cell module;
A converter unit converting the DC power from the bypass diode and including a plurality of interleaving converters;
An inverter unit for outputting AC power by using the converted DC power;
A control unit for controlling the inverter unit; And
Includes; a communication unit for outputting by adding solar power information to the AC power,
The control unit,
When the switching period of the plurality of interleaving converters is increased, a phase difference between the plurality of interleaving converters is changed so that a phase difference between each of the interleaving converters decreases. The method of claim 9,
The first communication unit,
A solar system, characterized in that further receiving current and voltage information of a power conversion module connected to the solar cell module, and the state information of the system. The method of claim 9,
The first communication unit,
A solar system, characterized in that further receiving a direct current power supply to which the solar power information is added through the system. The method of claim 9,
The first communication unit,
A photovoltaic system comprising receiving AC power to which the solar power information is added, based on a communication speed of 1 Mbps or more and a bandwidth of 2 to 30 MHz. The method of claim 9,
The communication device,
An output unit for outputting the monitoring information; solar system comprising a further. The method of claim 9,
The second communication unit,
A solar system, characterized in that the monitoring information is added to a wireless signal and output. The method of claim 9,
The second communication unit,
A photovoltaic system, characterized in that the monitoring information is added to a wired signal and output. delete The method of claim 9,
The communication unit,
A solar system, characterized in that for performing one-way communication for transmitting the information to the system. The method of claim 9,
The converter unit,
A solar system comprising: converting the DC power from the bypass diode to power and outputting a pseudo DC power. The method of claim 9,
The control unit,
Controlling the converter and the inverter,
A photovoltaic system comprising varying a switching period of the plurality of interleaving converters or varying a switching period of the plurality of interleaving converters while varying a phase difference for an operation period between the plurality of interleaving converters. The method of claim 9,
The power conversion module,
Solar system, characterized in that provided in the junction box attached to the rear surface of the solar cell module.

Images