Photovoltaic system

Abstract

A control module according to one embodiment of the present invention comprises: a switching unit for selectively connecting an output of a power conversion device or a system power supply to a load; and a control unit for monitoring the power conversion device, in which the control unit controls the photovoltaic module connected to the power conversion device.

Description

Technical Field

[0001] The present invention relates to a photovoltaic system, and more particularly, to a control module, a battery module, and a photovoltaic system for controlling a photovoltaic system. Background Art

[0002] Photovoltaic power generation is an environmentally friendly power generation method that can replace existing chemical power generation or nuclear power generation. Photovoltaic power generation includes a standalone type and a connection type. In the standalone type, a battery is connected to a converter, and in the connection type, a battery is connected to a power grid. Generally, standalone power generation includes a photovoltaic cell, a storage battery, a power conversion device, etc., and a grid-connected system is connected to the commercial power, so that the load grid line and power can be exchanged with each other.

[0003] In the case of a fire or other abnormality in a photovoltaic power generation panel, the voltage must be reduced to a certain level or below within a short time to protect workers from electric shock and for other reasons for subsequent processing. A technology capable of detecting an abnormal voltage and safely reducing the voltage is needed. Summary of the Invention

[0004] Technical Problem

[0005] The technical problem to be solved by the present invention is to provide a control module, a battery module, and a photovoltaic system for controlling a photovoltaic system.

[0006] Technical Solution

[0007] To solve the above technical problem, a control module according to an embodiment of the present invention includes: a switch unit for selectively connecting an output of a power conversion device or a system power supply to a load; and a control unit for monitoring the power conversion device, wherein the control unit controls a photovoltaic module connected to the power conversion device.

[0008] In addition, the control unit may control signal transmission from the power conversion device to the photovoltaic module.

[0009] In addition, when a rapid shutdown (RSD) situation occurs, the control unit may transmit a control signal to the power conversion device to block signal transmission to the photovoltaic module.

[0010] In addition, the control unit may include an energy management system (EMS).

[0011] In addition, the control unit communicates with the power conversion device using a first communication method, and the first communication method may be different from a second communication method that is a communication method between the power conversion device and the photovoltaic module.

[0012] In addition, the communication signal according to the first communication method can be converted into a communication signal according to the second communication method in the signal conversion unit included in the power conversion device.

[0013] Furthermore, the first communication method may include a CAN communication method, and the second communication method may include a PLC communication method.

[0014] In addition, the control unit can control multiple inverters.

[0015] In addition, the switch unit may include an automatic transfer switch (ATS).

[0016] In addition, the control unit can monitor the battery module connected to the power conversion device.

[0017] To solve the above technical problems, a battery module according to an embodiment of the present invention includes: a DC-DC converter that converts the output of the power conversion device; an energy storage unit connected to the DC-DC converter and performing charging or discharging; and a control unit that monitors the power conversion device, and the control unit controls a photovoltaic module connected to the power conversion device.

[0018] In addition, the control unit can control the signal transmission from the power conversion device to the photovoltaic module.

[0019] In addition, when a rapid shutdown (RSD) situation occurs, the control unit can transmit a control signal to the power conversion device to block the signal transmission to the photovoltaic module.

[0020] To solve the above technical problems, a photovoltaic system according to an embodiment of the present invention includes: a power conversion device that receives the output of the photovoltaic module and performs a first communication with the photovoltaic module; and a control module that selectively connects the output of the power conversion device or the grid power supply to a load, wherein the control module controls the photovoltaic module through a second communication with the power conversion device.

[0021] In addition, the control module may include any one of the above control modules.

[0022] Advantageous Effects

[0023] According to the embodiments of the present invention, the inverter, MLPE, battery, etc. can be centrally controlled from the standby box. Even when multiple inverters, MLPEs, and batteries are connected, they can be controlled by one standby box. The inverter and MLPE can be monitored, and the RSD operation can be performed from the standby box without adding a module configured as an independent accessory for the RSD operation. The standby box and the inverter communicate through the same or different communication as the communication between the inverter and the MLPE, thereby improving system compatibility. Brief Description of the Drawings

[0024] Figure 1 is a block diagram showing the connection relationship with other components of the control module according to an embodiment of the present invention.

[0025] Figure 2 is a block diagram of the control module according to an embodiment of the present invention.

[0026] Figure 3 and Figure 4 is a block diagram of the control module according to an embodiment of the present invention.

[0027] Figure 5 is a block diagram showing the connection relationship with other components of the battery module according to an embodiment of the present invention.

[0028] Figure 6 is a block diagram of the battery module according to an embodiment of the present invention.

[0029] Figure 7 is a block diagram of the photovoltaic system according to an embodiment of the present invention. Detailed Embodiments

[0030] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0031] However, the technical idea of the present invention is not limited to some embodiments to be described, but can be implemented in various forms, and within the scope of the technical idea of the present invention, one or more of the components can be selectively combined or replaced between embodiments.

[0032] In addition, unless clearly defined and described, the terms (including technical terms and scientific terms) used in the embodiments of the present invention can be interpreted as the meanings commonly understood by those skilled in the art, and common terms can be interpreted in consideration of the meaning in the context of the related technology, such as the terms defined in the dictionary.

[0033] In addition, the terms used in this specification are for describing the embodiments and are not intended to limit the present invention. In this specification, unless specifically stated in the phrase, the singular form may include the plural form, and when described as "at least one (or more than one) of A, B, and C", one or more combinations of all the combinable ones of A, B, and C can be included.

[0034] In addition, when describing the components of the embodiments of the present invention, terms such as first, second, A, B, (a), and (b) may be used.

[0035] These terms are only intended to distinguish the components from other components, and these terms do not limit the nature, order, or sequence of the components.

[0036] Moreover, when a component is described as being "connected", "coupled", or "interconnected" to another component, the component is not only directly connected, coupled, or interconnected to the other component, but may also include a situation where it is "connected", "coupled", or "interconnected" due to the presence of one or more other components between the other components.

[0037] In addition, when described as being "formed on" or "disposed on" the "upper (above)" or "lower (below)" of each component, the "upper (above)" or "lower (below)" not only includes the case where the two components are in direct contact, but also includes the situation where one or more other components are formed or disposed between the two components. Moreover, the expression "upper (above)" or "lower (below)" not only refers to the upward direction with respect to a certain component, but may also include the meaning of the downward direction.

[0038] A modified embodiment according to the present embodiment may simultaneously include some components of each embodiment and some components of other embodiments. That is to say, the modified embodiment may include one embodiment among various embodiments, but some components may be omitted, and some components of the corresponding other embodiments may be included. Or, vice versa. The features, structures, effects, etc. described in the embodiments are included in at least one embodiment, and are not limited to only one embodiment. In addition, the features, structures, effects, etc. illustrated in each embodiment can be combined, modified, and implemented by those of ordinary skill in the art to which the embodiments belong in other embodiments. Therefore, the content related to such combinations and modifications should be construed as being included within the scope of the embodiments.

[0039] Figure 1 is a block diagram showing the connection relationship with other components of a control module according to an embodiment of the present invention; Figure 2 is a block diagram of a control module according to an embodiment of the present invention; Figure 3 and Figure 4 is a block diagram of a control module according to an embodiment of the present invention; Figure 5 is a block diagram showing the connection relationship with other components of a battery module according to an embodiment of the present invention; Figure 6 is a block diagram of a battery module according to an embodiment of the present invention; and Figure 7 is a block diagram of a photovoltaic system according to an embodiment of the present invention.

[0040] The control module 110 according to an embodiment of the present invention includes a switching unit 111 and a control unit 112. The control module 110 according to an embodiment of the present invention is connected to a power conversion device 120, a power grid 130, and a load 140, and the control module 110 is a module that connects the power conversion device 120 and the load 140, or connects the power of the power grid 130 to the load 140, and may include a standby module or a communication module, or may be arranged in the standby module or the communication module. Here, the standby module may include a standby box, and may include a junction box or an ATS box, a distribution board, a distribution box, etc.

[0041] The switching unit 111 selectively connects the output of the power conversion device 120 or the power of the power grid 130 to the load 140. The power required by the load 140 may be supplied to the power grid 130, or may be supplied to the load 140 according to the power output by the power conversion device 120. The power conversion device 120 converts the output of the photovoltaic module 150 into standby power for the power grid 130. At this time, the switching unit 111 may selectively connect the power conversion device 120 or the power grid 130 as a power supply source for supplying power to the load 140. In addition, power may be supplied by the battery module 160 through the power conversion device 120. The battery module 160 is connected to the power conversion device 120 and is charged by the power conversion device 120. Here, the load 140 may be a device that uses the power generated by photovoltaic power generation. If the photovoltaic system is installed at home, the load 140 may be a device at home.

[0042] The switching unit 111 may include an automatic transfer switch (ATS). The automatic transfer switch 113 is a device that automatically switches the main power supply to the standby power supply when an abnormality such as a power outage occurs. If the main power supply resumes power supply while the standby power supply is connected, it may include a function of restoring the standby power supply to the normal power supply. In addition to the automatic transfer switch, the switching unit 111 may include other types of switching elements, such as MOSFETs or relays.

[0043] The control unit 112 monitors the power conversion device 120 and controls the photovoltaic module 150 connected to the power conversion device 120.

[0044] The power conversion device 120 is a device that converts the output of the photovoltaic module 150 into power suitable for the load 140 or the power grid 130. The power conversion device 120 can be a power conversion system (PCS) or an inverter. The power conversion device 120 can be connected to the photovoltaic module 150 that performs photovoltaic power generation. Here, the photovoltaic module 150 can be a photovoltaic (PV) module. The photovoltaic module 150 can include one or more photovoltaic cells, and the photovoltaic cells have different maximum power points according to the amount of sunlight, temperature, etc. To operate the photovoltaic cells at the maximum power point, a maximum power point tracking (MPPT) control can be performed on a module-by-module basis using an optimizer or a module-level power electronics device (MLPE). The power conversion device 120 connected to the photovoltaic module 150 equipped with the MLPE 151 can receive a voltage input through the MLPE 151.

[0045] The power conversion device 120 and the MLPE 151 of the photovoltaic module 150 can perform communication. The MLPE 151 can operate the photovoltaic module 150 by establishing a communication connection with the power conversion device 120. When the communication with the power conversion device 120 is not connected or the communication is blocked, the MLPE 151 can stop the operation of the photovoltaic module 150. The power conversion device 120 and the MLPE 151 can use a PLC communication method to perform communication. Power line communication (PLC) is a power line communication method in which a signal for communication is included in a signal transmitted through a power line and the signal is transmitted. When using the PLC communication method, communication can be performed only using the power line simultaneously with power transmission without a separate communication connection line. The MLPE 151 and the power conversion device 120 can communicate using various communication methods, such as CAN communication in addition to PLC communication.

[0046] The control unit 112 can monitor the power conversion device 120. The control unit 112 can monitor the power grid 130, the MLPE 151 of the photovoltaic module 150 and the battery module 160, and the power conversion device 120. That is, each component can be monitored to improve the energy efficiency of the entire photovoltaic system. The control unit 112 can include an energy management system (EMS).

[0047] The control unit 112 can charge the battery module 160 through the power conversion device 120 according to the amount of photovoltaic power generated by the photovoltaic module 150, connect the power conversion device 120 to the load 140 to transmit the power stored in the battery module 160 to the load 140, or connect the power grid 130 to the load 140 to effectively supply power to the load 140 when the amount of generated photovoltaic power or the charge amount in the battery module 160 is insufficient.

[0048] The control unit 112 can control the signal transmission from the power conversion device 120 to the photovoltaic module 150. The control unit 112 is not directly connected to the photovoltaic module 150, but is connected to the power conversion device 120, which controls the signal transmission to the photovoltaic module 150, thereby controlling the photovoltaic module 150. The control unit 112 communicates with the power conversion device 120 and accordingly allows the power conversion device 120 and the photovoltaic module 150 to communicate, enabling the power conversion device 120 to communicate with the photovoltaic module 150 through the power conversion device 120.

[0049] The control unit 112 communicates with the photovoltaic module 150 through the power conversion device 120 and can use this communication to control the operation of the photovoltaic module 150. In addition, the control unit 112 can monitor and control the battery module 160 connected to the power conversion device 120.

[0050] As described above, the photovoltaic module 150 operates when in communication connection with the power conversion device 120 and can stop operating when the communication with the power conversion device 120 is cut off. The photovoltaic module 150 can be connected as an array of multiple photovoltaic modules, and when one of the photovoltaic modules stops, the corresponding photovoltaic module can be bypassed.

[0051] When a rapid shutdown (RSD) situation occurs, the control unit 112 can send a control signal to the power conversion device 120 to block the signal transmission to the photovoltaic module 150. If the photovoltaic module 150 operates based on whether it is in communication with the power conversion device 120, this can be used to block the communication between the power conversion device 120 and the photovoltaic module 150 in case of an abnormal situation, thereby stopping the operation of the photovoltaic module 150.

[0052] The control unit 112 monitors the power conversion device 120 and can monitor the output of the photovoltaic module 150 input to the power conversion device 120. The input voltage input to the power conversion device 120 is monitored, and if the range of the input voltage is an abnormal range, the input voltage can be cut off. If an abnormality such as a fire occurs in the photovoltaic module 150, the voltage level of the input voltage is reduced. Therefore, if the input voltage within the abnormal range is input, the input voltage can be quickly cut off. If a fire occurs, firefighters and other workers may approach the photovoltaic panels, and due to the relatively high residual voltage, there may be a risk of electric shock. In this case, the control unit 112 can execute the rapid shutdown (RSD) function. Rapid shutdown (RSD) is a safety function and is a function that can quickly reduce the voltage if an abnormality occurs. During normal operation, RSD operates in a standby or sleep mode, and when an abnormality occurs, it operates in an operating or wake-up mode to quickly reduce the voltage.

[0053] When a rapid shutdown (RSD) situation occurs, the control unit 112 can send a control signal to the power conversion device 120 to prevent the signal from being transmitted to the photovoltaic module 150. The power conversion device 120 blocks the signal transmission to the photovoltaic module 150 according to the control signal, and the photovoltaic module 150 confirms that the signal reception from the power conversion device 120 is blocked and stops operating, so as to quickly block the operation of the photovoltaic module 150 when the RSD situation occurs.

[0054] The control unit 112 monitors and controls the states of the photovoltaic module 150 and the battery module 160 connected to the power conversion device 120 through communication with the power conversion device 120, and when an abnormality such as an RSD situation occurs, it can quickly block the operation of the photovoltaic module 150 through communication with the power conversion device 120, thereby protecting the entire system.

[0055] The control unit 112 communicates with the power conversion device 120 using a first communication method, and the power conversion device 120 can communicate with the photovoltaic module 150 using a second communication method. Here, the first communication method and the second communication method can be different from each other. For example, the first communication method can include a CAN communication method or an RS-485 communication method, and the second communication method can include a PLC communication method. Or, the second communication method can include a CAN communication method or an RS-485 communication method, and the first communication method can include a PLC communication method. The communication method between the control unit 112 of the control module 110 and the power conversion device 120 and the communication method between the power conversion device 120 and the photovoltaic module 150 can be different from each other, thereby improving compatibility. That is to say, the control unit 112 can communicate with the photovoltaic module 150 through the power conversion device 120 without directly communicating with the photovoltaic module 150, so that the photovoltaic module 150 can be controlled only by communicating with the power conversion device 120 regardless of the communication method between the power conversion device 120 and the photovoltaic module 150. Obviously, the first communication method and the second communication method can be the same.

[0056] The communication signal according to the first communication method can be converted by the signal conversion unit included in the power conversion device 120 into a communication signal according to the second communication method. When the first communication method and the second communication method are different from each other, it is difficult for the control unit 112 and the photovoltaic module 150 to perform communication. Therefore, it is necessary to convert the signal according to the first communication method into a signal according to the second communication method, or convert the signal according to the second communication method into a signal according to the first communication method. Each power conversion device 120 that performs communication includes a signal conversion unit, and the signal can be converted by the signal conversion unit into a signal with a different communication method. The signal can be converted by reconstructing the signal according to the first communication method according to the second communication method. Here, the signal conversion unit can be the microcontroller unit (MCU) of the power conversion device 120 and can include a pulse generator for PLC communication.

[0057] The control unit 112 can be connected to a plurality of power conversion devices 120. The power conversion device 120 can be an inverter, and a plurality of inverters can be connected, and a plurality of photovoltaic module arrays and a plurality of batteries can be connected to one inverter. The control unit 112 can control the plurality of power conversion devices 120 and each component connected thereto. Since the control unit 112 is located in the control module 110 rather than in the power conversion device 120, even if the number of power conversion devices 120 increases, the entire system can be controlled by a single control module 110.

[0058] As described above, not only does the control module 110 control the photovoltaic module 150, but the battery module 160 can also control the photovoltaic module 150. As Figure 5 and Figure 6 shown, the battery module 160 according to an embodiment of the present invention can include a power conversion device 120, a DC-DC converter 161, an energy storage unit 162, and a control unit 163.

[0059] The DC-DC converter 161 converts the output of the power conversion device 120. The DC-DC converter 161 converts the first voltage output from the power conversion device 120 into a second voltage suitable for charging the energy storage unit 162. The energy storage unit 162 is connected to the DC-DC converter 161 and charges or discharges. The energy storage unit 162 can include a plurality of battery cells. The control unit 163 monitors the power conversion device 120 and controls the photovoltaic module 150 connected to the power conversion device 120. The detailed description of the control unit 163 that controls the photovoltaic module 150 corresponds to the detailed description of the control unit 112 of the control module 110, so the repeated description is omitted below.

[0060] The control unit 163 can monitor and control the MLPE 151 of the photovoltaic module 150, the power conversion device 120 serving as an inverter, the DC-DC converter 161, and the energy storage unit 162. The control unit 163 can control the signal transmission from the power conversion device 120 to the photovoltaic module 150, and when a rapid shutdown (RSD) situation occurs, it can transmit a control signal to the power conversion device 120 to block the signal transmission to the photovoltaic module 150.

[0061] The control unit 163 can include an energy management system EMS, and the control unit 163 communicates with the power conversion device 120 using a first communication method, and the first communication method can be different from a second communication method, which is the communication method between the power conversion device 120 and the photovoltaic module 150. Additionally, the communication signal according to the first communication method can be converted into a communication signal according to the second communication method in a signal conversion unit included in the power conversion device 120. Here, the first communication method can include a CAN communication method, and the second communication method can include a PLC communication method.

[0062] As Figure 7 shown, the photovoltaic system 200 according to an embodiment of the present invention can be configured with a power conversion device 120 and a control module 110. The power conversion device 120 can receive the output of the photovoltaic module 150 and perform a first communication with the photovoltaic module 150, and the control module 110 can selectively connect the output of the power conversion device 120 or the power of the power grid 130 to the load 140. Here, the control module 110 can control the photovoltaic module 150 through a second communication with the power conversion device 120.

[0063] Since the control unit 163 for controlling the photovoltaic module 150 is located in the battery module 160, communication can be achieved only through the communication between DC signals, without the need for conversion between DC and AC signals in the power conversion device 120. Therefore, faster and more accurate communication can be achieved compared to using the control unit 112 of the control module 110.

[0064] Figure 7 The detailed description of each component of the photovoltaic system 200 corresponds to Figures 1 to 4 the detailed description of the control module 110 and the photovoltaic system, and thus, repeated descriptions are omitted.

[0065] The control module 110 includes a switch unit 111 and a control unit 112. The switch unit 111 selectively connects the output of the power conversion device 120 or the power from the power grid 130 to the load. The control unit 112 monitors the power conversion device 120, and the control unit 112 can control the photovoltaic module connected to the power conversion device. The control unit 112 can control the signal transmission from the power conversion device 120 to the photovoltaic module 150, and when a rapid shutdown (RSD) situation occurs, it can transmit a control signal to the power conversion device 120 to block the signal transmission to the photovoltaic module 150. Herein, the control unit may include an energy management system (EMS) 114. The control unit 112 communicates with the power conversion device 120 using a first communication method; and the first communication method may be different from a second communication method, which is the communication method between the power conversion device 120 and the photovoltaic module 150. In addition, the communication signal according to the first communication method can be converted by a signal conversion unit included in the power conversion device 120 into a communication signal according to the second communication method. Herein, the first communication method may include a CAN communication method, and the second communication method may include a PLC communication method.

[0066] The control unit 112 can control multiple inverters, the switch unit 111 may include an automatic transfer switch (ATS), and the control unit 112 can monitor the battery module 160 connected to the power conversion device 120.

[0067] The features, structures, effects, etc. described in the above embodiments are included in at least one embodiment and are not limited to one embodiment. In addition, the features, structures, effects, etc. shown in each embodiment can be combined, modified, and implemented by those of ordinary skill in the art to which the embodiment belongs in other embodiments. Therefore, the content related to such combinations and modifications should be construed as being included within the scope of the embodiments.

[0068] Those skilled in the art related to this embodiment will understand that the above description can be implemented in a modified form without departing from its basic features. Therefore, the disclosed method should be considered from an illustrative rather than a restrictive perspective. The scope of the present invention is indicated by the claims rather than the above description, and all differences within the equivalent scope thereof should be construed as being included in the present invention.

Claims

1. A control module, comprising: A switch unit for selectively connecting the output of a power conversion device or a grid power supply to a load; And A control unit for monitoring the power conversion device, Wherein, the control unit controls a photovoltaic module connected to the power conversion device.

2. The control module according to claim 1, Among them, The control unit controls the signal transmission from the power conversion device to the photovoltaic module.

3. The control module according to claim 1, Among them, When a rapid shutdown (RSD) situation occurs, the control unit transmits a control signal to the power conversion device to block the signal transmission to the photovoltaic module.

4. The control module according to claim 1, Among them, The control unit includes an energy management system (EMS).

5. The control module according to claim 1, Among them, The control unit communicates with the power conversion device using a first communication method, Wherein, the first communication method is different from a second communication method, and the second communication method is the communication method between the power conversion device and the photovoltaic module.

6. The control module according to claim 5, Among them, The communication signal according to the first communication method can be converted into a communication signal according to the second communication method in a signal conversion unit included in the power conversion device.

7. The control module according to claim 5, Among them, The first communication method includes a CAN communication method, Wherein, the second communication method includes a PLC communication method.

8. The control module according to claim 1, Among them, The control unit controls a plurality of inverters.

9. The control module according to claim 1, Among them, The switch unit includes an automatic transfer switch (ATS).

10. The control module according to claim 1, Among them, The control unit monitors a battery module connected to the power conversion device.

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