WO2024072174A1 - Photovoltaic module - Google Patents

Abstract

An optimizer module according to an embodiment of the present invention comprises: two input terminals connected to a cell string; a power conversion unit for converting power inputted via the input terminals; two output terminals connected to another optimizer module or the outside; and a control unit for controlling the power conversion unit in response to the power inputted via the input terminals.

Description

photovoltaic module

The present invention relates to a photovoltaic module, and more specifically, to a photovoltaic module in which an optimizer is individually connected to each photovoltaic cell-string.

Solar power generation is an eco-friendly energy generation method that is becoming widely used, replacing existing chemical or nuclear power generation. There are two types of solar power generation: independent type, where a battery is connected to a converter, and connected type, which is connected to the power system. In general, independent power generation consists of photovoltaic power generation, storage batteries, power conversion devices, etc., and power grid-connected system is connected to a commercial power source. It is configured to allow mutual exchange of power with the load system line.

The maximum power point of photovoltaic modules varies depending on the amount of sunlight, temperature, etc. To operate solar cells at the maximum power point, an optimizer or module-level power electronics (MLPE) that performs maximum power point tracking (MPPT) control on a module-by-module basis can be used.

A junction box is installed on the photovoltaic module to connect it to an external line. In order to connect the optimizer to the photovoltaic module, a number of cables and manual labor are required to connect them. Additionally, depending on the installation environment, there is a disadvantage that a separate device must be installed in the photovoltaic module to prevent electric shock.

The technical problem to be solved by the present invention is to provide a photovoltaic module in which an optimizer is individually connected to each photovoltaic cell-string.

In order to solve the above technical problem, the optimizer module according to an embodiment of the present invention includes a case body; a case cover covering the case body; and an optimizer disposed inside the case body, where the optimizer includes two input terminals and two output terminals.

In addition, the two input terminals are connected to output terminals at both ends of the cell string, and the optimizer includes a power conversion unit that converts the output power of the cell string; And it may include a control unit that controls the power conversion unit according to the output power of the cell string.

Additionally, the output terminal can be connected to another optimizer module or to the outside.

Additionally, the output terminal may be connected in series when connected to the other optimizer module.

Additionally, the inside of the case body may be filled with a heat dissipating material.

Additionally, the case body and the case cover may be formed to have a waterproof structure.

Additionally, the optimizer may be detachable from the case body.

Additionally, the optimizer may include a bypass unit connected in parallel between the two output terminals.

Additionally, the optimizer may include an auxiliary power unit that generates auxiliary power using the output power of the cell string.

In order to solve the above technical problem, a photovoltaic module according to an embodiment of the present invention includes a photovoltaic panel including a plurality of cell strings; and a plurality of optimizer modules that respectively control the output power of each cell string, and the optimizer module includes one of the optimizer modules described above.

Additionally, each of the optimizer modules may be spaced apart from each other and placed in an area corresponding to each cell string.

Additionally, each of the optimizer modules may be connected in series to each other through a connection part built into the photovoltaic panel.

Additionally, each of the optimizer modules may be connected to each other through a connection part outside the photovoltaic panel, or may be connected to an optimizer module of an external or other photovoltaic module.

In order to solve the above technical problem, the optimizer module according to the second embodiment of the present invention includes two input terminals connected to a cell string; A power conversion unit that converts power input to the input terminal; Two output terminals connected to other optimizer modules or externally; And a control unit that controls the power conversion unit according to the power input to the input terminal.

Additionally, the control unit may control the power conversion unit so that the output power of the cell string is maximized.

Additionally, the power conversion unit may include at least one of a buck converter, a boost converter, and a buck-boost converter.

Additionally, it may include a bypass unit connected in parallel between the two output terminals.

Additionally, the bypass unit may be conducted when the first current output from the power conversion unit is lower than the second current flowing through the output terminal.

Additionally, the bypass unit may include a diode.

Additionally, it may include an auxiliary power unit that generates auxiliary power using power input to the input terminal.

Additionally, the auxiliary power unit may operate in a step-down mode or a step-up mode.

In order to solve the above technical problem, a photovoltaic module according to a second embodiment of the present invention includes a photovoltaic panel including a plurality of cell strings; and a plurality of optimizer modules that respectively control the output power of each cell string, and the optimizer module includes one of the optimizer modules described above.

Additionally, each of the optimizer modules may be spaced apart from each other and placed in an area corresponding to each cell string.

According to embodiments of the present invention, the cables for connecting the photovoltaic panel and the optimizer can be reduced and work can be made easier.

1 is a block diagram of a photovoltaic module according to an embodiment of the present invention.

Figure 2 is a diagram for explaining maximum power point tracking control.

Figure 3 is a block diagram specifying the relationship between a cell-string and an optimizer according to an embodiment of the present invention.

Figure 4 shows the connection relationship between optimizers according to an embodiment of the present invention.

Figure 5 shows the location of each optimizer according to an embodiment of the present invention.

Figure 6 shows an implementation example of a photovoltaic module according to an embodiment of the present invention.

Figure 7 is a block diagram of an optimizer module according to an embodiment of the present invention.

Figure 8 shows an implementation example of an optimizer module according to an embodiment of the present invention.

Figure 9 is a block diagram of a photovoltaic module according to another embodiment of the present invention.

Figure 10 is a perspective view of an optimizer module according to an embodiment of the present invention.

Figure 11 shows the inside of the case of the optimizer module according to an embodiment of the present invention.

Figure 12 shows the connection relationship of a plurality of optimizer modules according to an embodiment of the present invention.

Figure 13 is a block diagram of a photovoltaic module according to another embodiment of the present invention.

Figure 14 shows the connection relationship of a plurality of photovoltaic modules according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

However, the technical idea of the present invention is not limited to some of the described embodiments, but may be implemented in various different forms, and as long as it is within the scope of the technical idea of the present invention, one or more of the components may be optionally used between the embodiments. It can be used by combining or replacing.

In addition, terms (including technical and scientific terms) used in the embodiments of the present invention, unless explicitly specifically defined and described, are generally understood by those skilled in the art to which the present invention pertains. It can be interpreted as meaning, and the meaning of commonly used terms, such as terms defined in a dictionary, can be interpreted by considering the contextual meaning of the related technology.

Additionally, the terms used in the embodiments of the present invention are for describing the embodiments and are not intended to limit the present invention.

In this specification, the singular may also include the plural unless specifically stated in the phrase, and when described as "at least one (or more than one) of A and B and C", it is combined with A, B, and C. It can contain one or more of all possible combinations.

Additionally, in describing the components of the embodiments of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and are not limited to the essence, order, or order of the component.

And, when a component is described as being 'connected', 'coupled', or 'connected' to another component, that component is directly 'connected', 'coupled', or 'connected' to that other component. In addition to cases, it may also include cases where the component is 'connected', 'coupled', or 'connected' by another component between that component and that other component.

Additionally, when described as being formed or disposed “on top” or “bottom” of each component, “top” or “bottom” means that the two components are directly adjacent to each other. This includes not only the case of contact, but also the case where one or more other components are formed or disposed between the two components. In addition, when expressed as “top” or “bottom,” the meaning of not only the upward direction but also the downward direction can be included based on one component.

Modifications according to this embodiment may include some components of each embodiment and some components of other embodiments. That is, the modified example may include one of the various embodiments, but some components may be omitted and some components of other corresponding embodiments may be included. Or, it could be the other way around. Features, structures, effects, etc. to be described in the embodiments are included in at least one embodiment and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects, etc. illustrated in each embodiment can be combined or modified and implemented in other embodiments by a person with ordinary knowledge in the field to which the embodiments belong. Therefore, contents related to such combinations and modifications should be interpreted as included in the scope of the embodiments.

Figure 1 is a block diagram of a photovoltaic module according to an embodiment of the present invention, Figure 2 is a diagram for explaining maximum power point tracking control, and Figure 3 is a diagram of a cell-string and optimizer according to an embodiment of the present invention. It is a block diagram specifying the relationship, and Figure 4 shows the connection relationship between optimizers according to an embodiment of the present invention, Figure 5 shows the location of each optimizer according to an embodiment of the present invention, and Figure 6 shows an implementation example of a photovoltaic module according to an embodiment of the present invention.

The photovoltaic module 100 according to an embodiment of the present invention includes a photovoltaic panel 110 and a plurality of optimizers 121, 122, and 123.

The photovoltaic module according to an embodiment of the present invention may be a photovoltaic panel and a module that converts power generated from the photovoltaic panel into power suitable for a load or battery. It can be expressed as a solar module, solar power generation module, etc.

Photovoltaic panel 110 includes a plurality of cell strings. A solar cell that performs solar power generation can be expressed as a cell string unit in which a plurality of cells are connected in series.

A cell string may include at least one cell, and when it includes a plurality of cells, the plurality of cells may be connected in series. The cell string may be a solar cell string containing solar cells. Strings of solar cells can form photovoltaic (PV) panels. The photovoltaic panel 110 may also be referred to as a solar panel or solar power panel. Solar cells generate photovoltaic power (PV, Photovoltaic) using the photoelectric effect. The photoelectric effect is the emission of electrons when light above a certain frequency hits a specific metal material. A pn junction is formed using a p-type semiconductor and an n-type semiconductor, and electricity is generated by using the electrons generated by the photoelectric effect to generate current. Create. Solar cells are formed using silicon, etc., and may be formed in a wafer form. Solar cells are located in fields that can easily receive sunlight, on the exterior walls of buildings, or on rooftops, and generate electricity using sunlight. At this time, the solar cell may be formed as BIPV (building-integrated photovoltaic power generation) that is formed integrally with the building.

Since the amount of power generated from one solar cell is insufficient to be used in a load or power system, it is used by connecting multiple solar cells in series rather than one solar cell to form a solar cell string. A suitable amount of power can be generated. A string of solar cells can be the basic unit of generating power. A photovoltaic panel can be formed by forming a plurality of cell strings, which are the basic units, into panels. Solar cells have different voltage-current characteristics, as shown in Figure 2, depending on the amount of sunlight, temperature, etc., and the maximum power point (MPP) also changes. (Generated power = voltage

A plurality of optimizers 121, 122, and 123 control the output power of each cell string 111, respectively.

The optimizer according to an embodiment of the present invention serves to control the solar cell to operate at the maximum power point (MPP), which is the operating point at which the solar cell has maximum power under each condition. Here, the optimizer may include module-level power electronics (MLPE).

This is called Maximum Power Point Tracking (MPPT), and the efficiency of solar power generation can be increased by using maximum power point tracking. In solar power generation, depending on the relationship between current and voltage and the characteristics of the relationship between voltage and power, the maximum power may not be the maximum voltage, but the power at about 80% of the maximum voltage. Since this maximum power point continues to change depending on the size of the voltage and current generated by the photovoltaic panel, it is necessary to continuously find the point where the maximum power point can be generated. That is, in order to follow the maximum power rather than the maximum voltage, the magnitude of the voltage and current can be varied to achieve the maximum power. In other words, the voltage can be decreased and the current increased in the direction of increasing power, or the voltage can be increased and the current can be decreased.

In order to perform maximum power point tracking for a plurality of cell strings, individual control of each cell string may be required. For example, if foreign matter interferes with light reception or there is a shadow in a specific cell string, the level of power generation may be different from that of other cell strings, so not only the operation mode that converts the power output from the cell string, but also operations other than power conversion It may be necessary. Operations that directly output the power output from the cell string without converting it or bypass the cell string may be necessary. For each situation, a device capable of multiple operating modes is needed that can operate in the most appropriate mode for the power output from each cell string. For example, in order to operate in the most appropriate mode for each situation, the optimizer 121 uses multiple modes of power conversion mode (first mode), input/output connection mode (second mode), and bypass mode (third mode). It can operate in mode. In addition to the power conversion mode, input/output connection mode, and bypass mode, other operation modes may be further included depending on the design.

Each of the optimizers 121, 122, and 123 may be spaced apart from each other and placed in an area corresponding to each cell string 111, 112, and 113. Each of the plurality of optimizers 121, 122, and 123 is composed of an independent module, and an area of the photovoltaic panel 110 corresponding to each cell string 111, 112, and 113 performs maximum power point tracking. can be placed in At this time, it may be located at a position corresponding to the output terminal of each cell string (111, 112, and 113). When using one optimizer to individually control each cell string, a large number of cables are required to connect each cell string and the optimizer, and the work of connecting the cables is necessary. The optimizer according to an embodiment of the present invention includes a plurality of optimizers 121, 122, and 123 that are separately formed to individually control each cell string, and the optimizer 121 is located in a separate location from the cell string 111. In this case, cables are still needed, so the optimizer 121 can be located on the photovoltaic panel area where each cell string is located. Through this, the optimizer 121, which is individually connected and individually controlled, is directly connected to the cell string 111, thereby reducing cable connections and making work easier.

The cell string 111 must receive sunlight and is disposed on the first side of the photovoltaic module 100, and each optimizer 121 has individually connected cell strings 111 on the opposite side of the first side. It can be placed on the second side. On the second side of the photovoltaic module 100, the output terminals of both ends of the cell string 111 are output, and the optimizer 121 is located at a position where the output terminals of both ends of the cell string 111 are output, and is directly connected to the input terminal of the optimizer. It can be connected.

The optimizer 121 may include input terminals 1211 and 1212, output terminals 1213 and 1214, a power conversion unit 1215, and a bypass unit 1216.

The input terminals 1211 and 1212 may include two input terminals connected to output terminals at both ends of each cell string 111. Each cell string 111 may have a plurality of solar cells 1111 to 1113 connected in series, as shown in FIG. 3, and two output terminals at both ends of the cell string 111 connected in series are output to the outside. At this time, both end output terminals may be directed to the second side of the photovoltaic module 100. Both output terminals of each cell string may be directly connected to the two input terminals 1211 and 1212 of each optimizer within the optimizer. The two input terminals 1211 and 1212 are respectively connected to output terminals at both ends of the cell string 111 and can receive power generated by the cell string 111.

Output terminals 1213 and 1214 are connected to other optimizers or external sources. The output terminals 1213 and 1214 may also include two output terminals. Optimizers can be connected in series, and when the optimizer is located between other optimizers, the two output terminals 1213 and 1214 are respectively connected to two other neighboring optimizers. The outputs of the plurality of optimizers 121 and 122 may be connected in series to output maximum power to the outside. When the optimizer is located at a position corresponding to an output terminal to the outside, one of the two output terminals 1213 and 1214 is connected to another neighboring optimizer, and the other is connected to the outside. Here, the external is a component located outside the photovoltaic module and may be a grid, load, or battery. Alternatively, it may be a power conversion device such as an inverter. The outputs of each optimizer are connected in series and output to the outside.

The output terminals 1213 and 1214 connected to the other optimizer may be connected through a connection portion 131 built into the photovoltaic panel 110. As shown in FIG. 4, the optimizer 121 may be connected to another optimizer through the connection portion 131 built into the photovoltaic panel 110. At this time, the connection part built into the photovoltaic panel 110 may include a bus bar or cable. At this time, the output terminal may be directly connected to the bus bar built into the photovoltaic panel 110, etc. At this time, the connection part 131 built into the photovoltaic panel 110 may be extended to the second side of the photovoltaic module 100, like output terminals at both ends of the cell string. The connection unit 131 built into the photovoltaic panel 110 may be directly connected to the two output terminals 1213 and 1214 of each optimizer inside the optimizer. At this time, the connection portion 131 built into the photovoltaic panel 110 may not be electrically connected to the cell string and the photovoltaic panel 110, but may be formed insulated from each other. When using the connection part 131 built into the photovoltaic panel 110, the connection location may be limited, but direct connection is possible without a separate cable.

Alternatively, the output terminals 1213 and 1214 connected to the other optimizer or the outside may be connected through an external connection part 132 rather than a connection part built into the photovoltaic panel 110. When using the connection part 132 outside the photovoltaic panel 110, a conductor such as a cable is used, so the connection location or connection type can be freely implemented. However, the cable may be exposed to the outside, increasing the risk of electric shock. Depending on the installation environment or work environment, the connection part 131 built into the photovoltaic panel 110 or the connection part 132 outside the photovoltaic panel 110 may be used.

The power conversion unit 1215 may convert the output power of each cell string 111 input through the input terminals 1211 and 1212 and output it to the output terminals 1213 and 1214. The power conversion unit 1215 can convert the voltage of the power of the cell string 111 and output it to the output terminals 1213 and 1214. At this time, the power conversion unit 1215 may perform maximum power point tracking for each cell string 111. If some of the cell strings among a plurality of cell strings generate lower voltage than other cell strings due to shading, etc., the voltage of the other cell strings is output as power in order to reduce loss and increase efficiency by reducing the voltage difference between each cell string. It is necessary to output it as is without conversion. At this time, the power conversion unit 1215 of each optimizer can adjust power conversion so that the voltage between cell strings is the same.

The power conversion unit 1215 may include at least one of a buck converter, a boost converter, and a buck-boost converter. The power conversion unit 120 may include a DC-DC converter, and in this case, it may include at least one of a buck converter, a boost converter, and a buck-boost converter. The power conversion unit 120 may be implemented as a buck converter that consists of an upper switch, a lower switch, and an inductor to lower the voltage. In addition, it can be implemented as a boost converter that increases the voltage by being composed of an inductor, an upper switch, and a lower switch, and is composed of a first upper switch, a first lower switch, an inductor, a second upper switch, and a second lower switch to increase the voltage. It can be implemented as a buck-boost converter to lower or increase . Capacitors may be connected in parallel to the input and output terminals of each converter.

The bypass unit 1216 is connected in parallel between the two output terminals 1213 and 1214.

The bypass unit 1216 can create a bypass path in the output terminals 1213 and 1214 that bypasses the connection of the input terminals 1211 and 1212 connected to the power conversion unit 120 or the cell string 111. there is. A bypass path can be created to pass power to an external source or to another optimizer without performing power conversion. For example, when a failure occurs in the photovoltaic module including the cell string or the input terminals 1211 and 1212 are not fastened and there is no power input to the power conversion device, the bypass unit 1216 provides a bypass path. can be provided. In addition, when a hot-spot occurs in the photovoltaic panel, the bypass unit 1216 may provide a bypass path for the output current and reduce the current flowing through the photovoltaic panel to suppress heat generation. Through this, if a current greater than the current that the photovoltaic panel can output is forcibly conducted, the impedance of the photovoltaic panel increases, thereby preventing an increase in heat generation.

The power conversion unit 1215 or bypass unit 1216 may be operated by a control unit, and the control unit may transmit a control signal to each component to operate in the most appropriate mode according to information such as input/output voltage, current, and temperature. . Additionally, it can operate in the corresponding mode according to a control signal from an external controller or a user's input.

As described above, the optimizer that individually controls each cell string 111 is located at the position of the corresponding cell string 111, as shown in FIG. 5. The photovoltaic module according to an embodiment of the present invention may be a smart photovoltaic module (PV module) including a cell string optimizer, and is electrically connected to one or more cell strings 111 consisting of at least one cell and individual cell strings. may include a cell string optimizer. The output of an optimizer can be connected in series with another optimizer. As shown in FIG. 6, it may include a plurality of cell strings and each optimizer, and the plurality of optimizers may be connected through a conductor built into the photovoltaic panel when connected in series (Connection #1). Alternatively, when connected in series (Connection #2), it can be connected through an external conductor. The optimizer's generated power can be output to the output terminal. The optimizer can vary at least one parameter related to a cell string to optimize the power generation of the corresponding cell string. It may include at least one power conversion unit for optimizing power generation, and the power conversion unit may be composed of Buck, Boost, and Buck-Boost converters. The optimizer may include a diode connected in parallel to the output terminal to optimize the power generation of the photovoltaic module. To prevent electric shock, the optimizer can block individual cell-string voltages. Additionally, the photovoltaic module may include a conductor (cable) for connection to other photovoltaic modules. Additionally, the optimizer may be electrically connected to an array consisting of multiple cell-strings wired in series or parallel, or in series/parallel. In other words, input may be received from multiple cell strings rather than one cell string.

Figure 7 is a block diagram of an optimizer module according to an embodiment of the present invention, Figure 8 shows an implementation example of the optimizer module according to an embodiment of the present invention, and Figure 9 is a block diagram of an optimizer module according to another embodiment of the present invention. This is a block diagram of a photovoltaic module. The detailed description of each component in FIGS. 7 to 9 corresponds to the detailed description of the photovoltaic module in FIGS. 1 to 6, and overlapping descriptions will be briefly described below.

The optimizer module 200 according to an embodiment of the present invention consists of input terminals 1211 and 1212, a power conversion unit 1215, output terminals 1213 and 1214, and a control unit 1217, and an auxiliary power unit 1218. , may include a bypass unit 1216.

Input terminals 1211 and 1212 are connected to the cell string 111. It may include two input terminals to be connected to both ends of the cell string 111, respectively. The output power of the cell string 111 may be input to the input terminals 1211 and 1212. One of the input terminals 1211 and 1212 may be connected to the (+) terminal of the cell string 111, and the other may be connected to the (-) terminal of the cell string 111.

The power conversion unit 1215 converts the power input to the input terminal 1211.

The power conversion unit 1215 may convert the output power of each cell string 111 input through the input terminals 1211 and 1212 and output it to the output terminals 1213 and 1214. The power conversion unit 1215 can convert the voltage of the power of the cell string 111 and output it to the output terminals 1213 and 1214. At this time, the power conversion unit 1215 may perform maximum power point tracking for each cell string 111. If some of the cell strings among a plurality of cell strings generate lower voltage than other cell strings due to shading, etc., the voltage of the other cell strings is output as power in order to reduce loss and increase efficiency by reducing the voltage difference between each cell string. It is necessary to output it as is without conversion. At this time, the power conversion unit 1215 of each optimizer can adjust power conversion so that the voltage between cell strings is the same.

The power conversion unit 1215 may include at least one of a buck converter, a boost converter, and a buck-boost converter. The power conversion unit 120 may include a DC-DC converter, and in this case, it may include at least one of a buck converter, a boost converter, and a buck-boost converter. The power conversion unit 120 may be implemented as a buck converter that consists of an upper switch, a lower switch, and an inductor to lower the voltage. In addition, it can be implemented as a boost converter that increases the voltage by being composed of an inductor, an upper switch, and a lower switch, and is composed of a first upper switch, a first lower switch, an inductor, a second upper switch, and a second lower switch to increase the voltage. It can be implemented as a buck-boost converter to lower or increase . Capacitors may be connected in parallel to the input and output terminals of each converter.

Output terminals 1213 and 1214 are connected to other optimizer modules or to the outside.

The output terminals 1213 and 1214 may also include two output terminals. Optimizer modules may be connected in series, and if the optimizer module is located between other optimizer modules, the two output terminals 1213 and 1214 may be connected to two other neighboring optimizer modules, respectively, and a plurality of optimizer modules may be connected in series. The output of the miser module is connected in series so that maximum power can be output externally. When the optimizer module is located in a position corresponding to an output terminal to the outside, one of the two output terminals (1213, 1214) can be connected to another neighboring optimizer module, and the other can be connected to the outside. there is. Here, the external is a component located outside the optimizer module and may be a grid, load, or battery. Alternatively, it may be a power conversion device such as an inverter.

The control unit 1217 controls the power conversion unit 1215 according to the power input to the input terminal 1211. The control unit 1217 controls the power conversion unit 1215 to convert the power input to the input terminal 1211. When the output power of the cell string 111 input to the input terminal 1211 is maximized, the control unit 1217 can control the power conversion unit 1215. The control unit can transmit control signals to each component to operate in the most appropriate mode according to information such as input/output voltage, current, and temperature. Additionally, it can operate in the corresponding mode according to a control signal from an external controller or a user's input.

The control unit 1217 can detect and monitor data on the input terminal side, the output terminal side, and inside the optimizer module, and control the power conversion unit 1215 accordingly. For example, the power of the cell string 111 input to the input terminal 1211, the output power or output current of the power conversion unit 1215, and the current flowing in the output terminal 1213 can be detected. Additionally, the control unit 1217 can control the auxiliary power unit 1218, the bypass unit 1216, etc.

The bypass unit 1216 may be connected in parallel between the two output terminals 1213 and 1214.

The bypass unit 1216 may create a bypass path between the output terminals 1213 and 1214 that bypasses the connection with the power conversion unit 1215. A bypass path can be created to connect another optimizer module externally or directly to another optimizer module without performing power conversion. For example, when a failure occurs in the photovoltaic module including the cell string or the input terminals 1211 and 1212 are not fastened and there is no or low power input to the power conversion unit 1215, the bypass unit 1216 A bypass path can be provided. In addition, when a hot-spot occurs in the photovoltaic panel, the bypass unit 1216 may provide a bypass path for the output current and reduce the current flowing through the photovoltaic panel to suppress heat generation. Through this, if a current greater than the current that the photovoltaic panel can output is forcibly conducted, the impedance of the photovoltaic panel increases, thereby preventing an increase in heat generation.

The bypass unit 1216 may be conducted when the first current output from the power conversion unit 1215 is lower than the second current flowing through the output terminal. If the first current converted and output inside the optimizer module 200 is lower than the second current flowing in the output terminal 1213 connected to another optimizer module, the optimizer module 200 is supplied from the other output terminal 1213. ) Current can flow inside. As a result, errors such as failures may occur in the optimizer module 200, or power may be wasted. Therefore, in this case, the current flowing through the output terminal 1213 flows through the bypass unit 1216, thereby bypassing the optimizer module 200. Here, the bypass unit 1216 may include a diode. Diodes only allow current to flow in one direction, so only current in that direction can be bypassed.

The auxiliary power unit 1218 can generate auxiliary power using power input to the input terminal 1211. The optimizer module 200 needs auxiliary power to convert power or perform control. The auxiliary power unit 1218 may generate auxiliary power using power input to the input terminal 1211 and provide the generated auxiliary power to the power conversion unit 1215 or the control unit 1217.

The auxiliary power unit 1218 may operate in a step-down mode or a step-up mode. The power input to the input terminal 1211 may vary depending on the amount of photovoltaic power generation, but the auxiliary power required for the power conversion unit 1215 or the control unit 1217 to operate may not change. Therefore, if the voltage of the input power is lower than the voltage of the auxiliary power source, the auxiliary power unit 1218 operates in step up mode, and if the voltage of the input power is higher than the voltage of the auxiliary power source, the auxiliary power unit 1218 operates in step up mode. It can operate in step down mode.

The optimizer module 200 may be implemented with a circuit diagram as shown in FIG. 8. The optimizer module 200 is a module that optimizes the output power of the cell string, and may include a DC-DC converter, which is the power conversion unit 1215, and a controller, which is the control unit 1217. The DC-DC converter receives the power generated from the cell string through the input terminal, converts the power, and outputs it to the output terminal. The controller can detect at least one parameter or control the DC-DC converter according to the detected parameters. The controller controls the DC-DC converter to maximize the power generated from the photovoltaic panel. Additionally, the bypass unit 1216 may include a bypass diode. The bypass diode is conducted when the second current, I_out current, is higher than the first current, I_DC-DC current, and current flows, thereby bypassing I_out. Additionally, it may include AUX, which is an auxiliary power supply unit 1218. The auxiliary power unit receives the voltage from the cell string and generates the power needed for the controller and DC-DC converter. At this time, the auxiliary power unit may operate in at least one step-down or step-up mode.

Here, the DC-DC converter may be composed of at least one Buck, Boost, and Buck-boost converter, and the optimizer module connected to a plurality of cell strings may be connected in series. Through series connection, a voltage higher than the output voltage of an individual cell-string optimizer module can be formed.

A photovoltaic module according to an embodiment of the present invention includes a photovoltaic panel 110 including a plurality of cell strings 111, 112, and 113, and a plurality of optimizer modules 200-1 and 200 that respectively control the output power of each cell string. -2, 200-3). At this time, each of the optimizer modules may be spaced apart from each other and placed in an area corresponding to each cell string.

The output terminals 1213 and 1214 connected to the other optimizer may be connected through a connection portion 131 built into the photovoltaic panel 110. As shown in FIG. 9 , the optimizer module 200-1 may be connected to another optimizer module 200-2 through the connection portion 131 built into the photovoltaic panel 110. At this time, the connection part built into the photovoltaic panel 110 may include a bus bar or cable. At this time, the output terminal may be directly connected to a bus bar built into the photovoltaic panel 110, etc. At this time, the connection portion 131 built into the photovoltaic panel 110 may be extended to the second side of the photovoltaic module, like output terminals at both ends of the cell string. The connection unit 131 built into the photovoltaic panel 110 may be directly connected to the two output terminals 1213 and 1214 of each optimizer inside the optimizer. At this time, the connection portion 131 built into the photovoltaic panel 110 may not be electrically connected to the cell string and the photovoltaic panel 110, but may be formed insulated from each other. When using the connection part 131 built into the photovoltaic panel 110, the connection location may be limited, but direct connection is possible without a separate cable.

Alternatively, the output terminals 1213 and 1214 connected to the other optimizer or the outside may be connected through an external connection part 132 rather than a connection part built into the photovoltaic panel 110. When using the connection part 132 outside the photovoltaic panel 110, a conductor such as a cable is used, so the connection location or connection type can be freely implemented. However, the cable may be exposed to the outside, increasing the risk of electric shock. Depending on the installation environment or work environment, the connection part 131 built into the photovoltaic panel 110 or the connection part 132 outside the photovoltaic panel 110 may be used.

Figure 10 is a perspective view of an optimizer module according to an embodiment of the present invention, Figure 11 shows the inside of a case of the optimizer module according to an embodiment of the present invention, and Figure 12 is a plurality of diagrams according to an embodiment of the present invention. It shows the connection relationship of the optimizer module, Figure 13 is a block diagram of a photovoltaic module according to another embodiment of the present invention, and Figure 14 shows the connection relationship of a plurality of photovoltaic modules according to an embodiment of the present invention. It is shown. The detailed description of each component in FIGS. 10 to 14 corresponds to the detailed description of the photovoltaic module in FIGS. 1 to 9, and overlapping descriptions will be briefly described below.

The optimizer module 300 according to an embodiment of the present invention includes a case and an optimizer 320 disposed inside the case. The optimizer 320 consists of input terminals 331 and 332, a power conversion unit 320, and output terminals 342 and 3434, and may include an auxiliary power unit and a bypass unit.

The case 310 includes a case body and a case cover (not shown) covering the case body, and may include an optimizer 320 disposed inside the case body. The optimizer 300 may include two input terminals 321 and 332 and two output terminals 341 and 342.

Two input terminals 331 and 332 are connected to output terminals at both ends of the cell string, and the optimizer 320 controls a power conversion unit that converts the output power of the cell string and a power conversion unit according to the output power of the cell string. It may include a control unit that does.

The inside of the case 310 main body may be filled with a heat dissipation material. When converting power, heat is generated, and to prevent errors due to heat, the heat can be radiated to the outside. The inner space of the case 310 can be filled with silicone or epoxy material.

The inside of the case 310 may be formed into a waterproof structure. The case 310 may be formed on one side of the photovoltaic module, and since it is located outdoors, it may be exposed to rain and may be formed to have a waterproof structure. As shown in Figure 10, a waterproof structure can be formed in the optimizer 320 connected to each connection terminal. That is, by forming a waterproof case internal structure inside the case and placing the optimizer 320 inside the waterproof structure, the components placed in the optimizer 320 can be protected.

The optimizer 320 may be detachable from the case 310 main body. The optimizer 320 can be attached or detached from the case 310 body by being connected to or disconnected from the input terminals 331 and 332 or the output terminals 341 and 342. At this time, each terminal can be screwed together. If a failure occurs in the optimizer 320, replacement or recovery work can be performed by attaching and detaching only the optimizer 320, not the entire optimizer module 300. Alternatively, it may be placed on the case 310 body in various ways, such as hook coupling or soldering.

The input terminals 331 and 332 are connected to the light discharge panel of the photovoltaic module on which the optimizer module 300 is mounted and can receive the output power of the cell string. The cell string 111 connected in series can have two output terminals at both ends exposed to the outside, and the output terminals at both ends can be output to the second side of the photovoltaic module 100. Both output terminals of each cell string may be directly connected to the two input terminals 331 and 332 of each optimizer module 300 inside the case 320. The two input terminals 331 and 332 are respectively connected to output terminals at both ends of the cell string 111 and can receive power generated by the cell string 111.

Output terminals 341 and 342 are connected to other optimizer modules or to the outside. The output terminals 341 and 342 may also include two output terminals. Optimizer modules may be connected in series, and when the corresponding optimizer module is located between other optimizer modules, the two output terminals 341 and 342 are respectively connected to two other neighboring optimizer modules. The outputs of a plurality of optimizer modules can be connected in series to output maximum power to the outside. When the optimizer module is located in a position corresponding to an output terminal to the outside, one of the two output terminals 341 and 342 may be connected to another neighboring optimizer module, and the other may be connected to the outside. Here, the external is a component located outside the photovoltaic module and may be a grid, load, or battery. Alternatively, it may be a power conversion device such as an inverter. The outputs of each optimizer are connected in series and output to the outside.

The output terminals 341 and 342 connected to the other optimizer modules may be connected through a connection portion 131 built into the photovoltaic panel 110. As shown in FIGS. 12 and 13 , the optimizer module 300-1 may be connected to another optimizer module 300-2 through the connection portion 131 built into the photovoltaic panel 110. At this time, the connection part built into the photovoltaic panel 110 may include a bus bar or cable. At this time, the output terminal may be directly connected to the bus bar built into the photovoltaic panel 110, etc. At this time, the connection part 131 built into the photovoltaic panel 110 may be extended to the second side of the photovoltaic module 100, like output terminals at both ends of the cell string. The connection portion 131 built into the photovoltaic panel 110 may be directly connected to the two output terminals 341 and 342 of each optimizer module and the optimizer module case 310. At this time, the connection portion 131 built into the photovoltaic panel 110 may not be electrically connected to the cell string and the photovoltaic panel 110, but may be formed insulated from each other. When using the connection part 131 built into the photovoltaic panel 110, the connection location may be limited, but direct connection is possible without a separate cable.

Alternatively, the output terminals 341 and 342 connected to the other optimizer or the outside may be connected through an external connection part 132 rather than a connection part built into the photovoltaic panel 110. When using the connection part 132 outside the photovoltaic panel 110, a conductor such as a cable is used, so the connection location or connection type can be freely implemented. However, the cable may be exposed to the outside, increasing the risk of electric shock. Depending on the installation environment or work environment, the connection part 131 built into the photovoltaic panel 110 or the connection part 132 outside the photovoltaic panel 110 may be used.

The output terminals 341 and 342 may be connected to other optimizer modules or the outside, and the output terminals 341 and 342 may be connected in series when connected to other optimizer modules. The output terminals 341 and 342 may be connected to a conductor such as a cable or bus bar that is introduced into the case 310 through a hole formed on the outside of the case 310 through a screw connection.

Case 310 may be composed of a case body and a case cover, and case 310 may include a waterproof function. Additionally, the inside of the case 310 can be filled with a material capable of heat transfer. For example, the empty space inside the case 310 can be filled with silicon or epoxy materials that facilitate heat transfer. The optimizer that optimizes the sal string is detachable from the case 310 and can be easily replaced. It can be electrically connected to the optimizer module of a cell-string located in another photovoltaic panel through the output terminal. At this time, to facilitate connection with other photovoltaic panels, the output terminal may be connected to a conductor such as a cable. The output terminal can be connected through a conductor built into the photovoltaic panel, and the conductor built into the photovoltaic panel can be replaced with a cable not built into the photovoltaic panel.

The optimizer 320 may be formed with a circuit configuration placed on a substrate inside the case 310. The optimizer 320 is composed of input terminals 331 and 332, a power conversion unit, and output terminals 342 and 3434, and may include an auxiliary power unit and a bypass unit.

The power conversion unit converts the power input to the input terminals 331 and 332. At this time, the control unit controls the power conversion unit according to the power input to the input terminals 331 and 332. The control unit can control the power conversion unit so that the output power of the cell string is maximized. The power conversion unit may include at least one of a buck converter, a boost converter, and a buck-boost converter.

The bypass unit may be connected in parallel between the two output terminals 341 and 342, and may be conductive between the output terminals to form a bypass path. The auxiliary power unit may generate auxiliary power using the output power of the cell string and provide it to the power conversion unit or control unit.

A photovoltaic module according to an embodiment of the present invention includes a photovoltaic panel 110 including a plurality of cell strings 111, 112, and 113, and a plurality of optimizer modules 300-1 and 300 that respectively control the output power of each cell string. -2, 300-3). At this time, each of the optimizer modules may be spaced apart from each other and placed in an area corresponding to each cell string.

The output terminals 341 and 342 connected to the other optimizer may be connected through a connection portion 131 built into the photovoltaic panel 110. As shown in FIGS. 12 and 13 , the optimizer module 300-1 may be connected to another optimizer module 300-2 through the connection portion 131 built into the photovoltaic panel 110. The connection portion 131 built into the photovoltaic panel 110 may not be electrically connected to the cell string and the photovoltaic panel 110, but may be formed insulated from each other. When using the connection part 131 built into the photovoltaic panel 110, the connection location may be limited, but direct connection is possible without a separate cable.

Alternatively, the output terminals 341 and 342 connected to the other optimizer or the outside may be connected through an external connection part 132 rather than a connection part built into the photovoltaic panel 110. When using the connection part 132 outside the photovoltaic panel 110, a conductor such as a cable is used, so the connection location or connection type can be freely implemented. However, the cable may be exposed to the outside, increasing the risk of electric shock. Depending on the installation environment or work environment, the connection part 131 built into the photovoltaic panel 110 or the connection part 132 outside the photovoltaic panel 110 may be used.

A plurality of photovoltaic modules 410, 420, and 430 may be connected. As shown in FIG. 14, a plurality of photovoltaic modules 410, 420, and 430 may be connected to each other in series through a conductor 441 or connected to the outside through a conductor 442 and 443. Each photovoltaic module 410 may include a photovoltaic panel 411 and the optimizer module 300 described above.

As described above, by placing the optimizer module in a position corresponding to the output terminal of the cell string, the cables for connecting the photovoltaic panel and the optimizer can be reduced and work can be made easier.

Those skilled in the art related to this embodiment will understand that the above-described base material can be implemented in a modified form without departing from the essential characteristics. Therefore, the disclosed methods should be considered from an explanatory rather than a restrictive perspective. The scope of the present invention is indicated in the claims rather than the foregoing description, and all differences within the equivalent scope should be construed as being included in the present invention.

Claims (10)

1. Case body;

   a case cover covering the case body; and

   Includes an optimizer disposed inside the case body,

   The optimizer is an optimizer module including two input terminals and two output terminals.
2. According to paragraph 1,

   The two input terminals are connected to output terminals at both ends of the cell string,

   The optimizer is

   A power conversion unit that converts the output power of the cell string; and

   An optimizer module including a control unit that controls the power conversion unit according to the output power of the cell string.
3. According to paragraph 1,

   The output terminal is an optimizer module that is connected to another optimizer module or the outside.
4. According to paragraph 3,

   The output terminal is an optimizer module that is connected in series when connected to the other optimizer module.
5. According to paragraph 1,

   The optimizer module is filled with heat dissipation material inside the case body.
6. According to paragraph 1,

   The optimizer module wherein the case body and the case cover are formed of a waterproof structure.
7. According to paragraph 1,

   The optimizer is an optimizer module that is detachable from the case body.
8. According to paragraph 1,

   The optimizer is

   An optimizer module including a bypass unit connected in parallel between the two output terminals.
9. According to paragraph 2,

   The optimizer is

   An optimizer module including an auxiliary power unit that generates auxiliary power using the output power of the cell string.
10. A photovoltaic panel including a plurality of cell strings; and

    Comprising a plurality of optimizer modules that respectively control the output power of each cell string,

    The optimizer module is a photovoltaic module including the optimizer module of claim 1.

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