Two-terminal rapid shutdown device for solar power generation system

Abstract

The present invention relates to a two-terminal rapid shutdown device for a solar power generation system. The rapid shutdown device of a two-terminal structure for each solar panel may be provided by: a transmitter that generates a high-frequency current and transmits the current via a connection line electrically connecting a plurality of solar panels; and a plurality of receivers that switch an electrical connection between the two terminals by using the power of the high-frequency current flowing in the connection line while each of the two terminals is connected between two neighboring solar panels among the plurality of solar panels.

Description

2-terminal rapid cutoff device for photovoltaic power generation systems

[0001] This relates to a rapid shutdown device used in a photovoltaic power generation system.

[0002] A photovoltaic power generation system generally consists of multiple solar panels that produce direct current (DC) power using sunlight, an inverter that converts the DC power produced by the panels into alternating current (AC), and a distribution panel that distributes the AC power output from the inverter. Recently, several countries have enacted or are in the process of enacting safety regulations for photovoltaic power generation systems that mandate the installation of rapid shutdown devices. For example, the U.S. National Electrical Code (NEC) mandates the installation of rapid shutdown devices in photovoltaic power generation systems.

[0003] Since high-voltage DC power is generated for each solar panel in a photovoltaic power generation system, it is necessary to cut off the current flow for each solar panel to prevent electric shock to workers or firefighters during maintenance work or in the event of a fire. The rapid cutoff device plays a role in preventing electrical hazards, such as electric shock to workers or firefighters, by cutting off the current flow for each solar panel. Conventional rapid cutoff devices are mostly designed with a four-terminal structure for each solar panel. Of the four terminals in a conventional rapid cutoff device, two terminals are used to connect to two terminals of the junction box of each solar panel, and the remaining two terminals are used to supply the power required to control the electrical connection between the two terminals connected to the two terminals of the junction box of each solar panel.

[0004] In the case of conventional 4-terminal rapid disconnectors, there were problems such as high installation and maintenance costs due to the increased number of contacts per solar panel to four compared to the photovoltaic power generation system before installation, which complicates the installation process and increases the wiring used to connect the solar panels. In particular, there was a problem where the overall efficiency of the photovoltaic power generation system decreased due to the increase in the total wire length resulting from the increased wiring used to connect the solar panels. Furthermore, there was a problem where the possibility of arc generation increased as the number of contacts per solar panel increased.

[0005] The invention provides a rapid disconnection device with a two-terminal structure capable of rapidly disconnecting the electrical connection between two adjacent solar panels using only two terminals for each solar panel, and a photovoltaic power generation system including the same. The invention is not limited to the technical problems described above, and other technical problems may be derived from the following description.

[0006] A two-terminal rapid disconnection device for a photovoltaic power generation system according to one aspect of the present invention comprises: a transmitter that generates a high-frequency current and transmits the generated high-frequency current through a connecting line so that the generated high-frequency current flows through a connecting line that electrically connects a plurality of photovoltaic panels; and a plurality of receivers that receive the high-frequency current flowing through the connecting line while each of the two terminals is connected between two adjacent photovoltaic panels of the plurality of photovoltaic panels, and switch the electrical connection between the two terminals by using the power of the received high-frequency current to switch the electrical connection between the two adjacent photovoltaic panels. When the high-frequency current flows through the connecting line, the electrical connection between the two terminals is turned on, thereby turning on the electrical connection between the two adjacent photovoltaic panels, and when the high-frequency current does not flow through the connecting line, the electrical connection between the two terminals is turned off, thereby turning off the electrical connection between the two adjacent photovoltaic panels.

[0007] The plurality of solar panels are connected in series with each other by the connecting line, and each receiver is inserted in series into the connecting line portion positioned between each of the two adjacent solar panels, so that one of the two terminals of each receiver is connected to the positive terminal of one of the two adjacent solar panels through the connecting line, and the other of the two terminals of each receiver is connected to the negative terminal of the other of the two adjacent solar panels through the connecting line, and direct current output from the plurality of solar panels and high-frequency current transmitted by the transmitter can flow through the connecting line.

[0008] Each of the above receivers may include a MOSFET installed between the two terminals of each receiver and switching the electrical connection between the two terminals of each receiver using the power of the received high-frequency current, thereby switching the electrical connection between the positive terminal of one solar panel and the negative terminal of the other solar panel.

[0009] Each of the above receivers further includes a high-frequency detector that receives the high-frequency current flowing in the connection line by detecting the high-frequency current flowing in the connection line from a change in the magnetic field around the connection line caused by the high-frequency current flowing in the connection line, and the MOSFET can switch the electrical connection between the two terminals using the power of the high-frequency current detected by the high-frequency detector.

[0010] The high-frequency detector comprises: a magnetic core formed in a ring shape having a hollow and arranged to pass through the hollow to focus a magnetic field generated from a current flowing in the connecting line; and a wire that detects the high-frequency current among the current flowing in the connecting line by winding the magnetic core a plurality of times in a manner that passes through the hollow of the magnetic core and then passes through the hollow of the magnetic core again, and the frequency band of the high-frequency current detected by the wire can be determined by the number of times the wire is wound around the magnetic core.

[0011] Each of the above receivers further includes a control signal generating unit that generates a control signal for controlling the switching operation of the MOSFET by rectifying and transforming the high-frequency current detected by the high-frequency detection unit, wherein the drain terminal of the MOSFET is connected to one of the two terminals of each receiver and the source terminal of the MOSFET is connected to the other of the two terminals of each receiver, and a control signal generated by the control signal generating unit is input to the gate terminal of the MOSFET, and when the voltage of the control signal input to the gate terminal of the MOSFET is less than the threshold voltage of the MOSFET, the electrical connection between the two terminals of each receiver is turned off, and when the voltage of the control signal input to the gate terminal of the MOSFET is greater than or equal to the threshold voltage of the MOSFET, the electrical connection between the two terminals of each receiver can be turned on.

[0012] Each of the above receivers further includes a capacitor connected between the drain terminal and the source terminal of the MOSFET, and among the DC and high-frequency currents flowing in the connection line, the DC current passes between the drain terminal and the source terminal of the MOSFET and flows between the two terminals when the voltage of the control signal input to the gate terminal of the MOSFET is greater than or equal to the threshold voltage of the MOSFET, and among the DC and high-frequency currents flowing in the connection line, the high-frequency current passes through the capacitor and flows between the two terminals.

[0013] The transmitter generates the high-frequency current by using a portion of the output power of an inverter that receives direct current generated by the power generation of the plurality of solar panels through the connection line and converts it into alternating current, and when the power output of the inverter is cut off, the electrical connection between the two terminals of each receiver inserted in series in the connection line portion placed between each of the two adjacent solar panels can be turned off.

[0014] The transmitter includes a pulse generator that generates a pulse signal in which high and low sections alternate, and the high-frequency current may have the form of alternating current in which the direction of current flow is periodically reversed according to the alternation of high and low sections of the pulse signal generated by the pulse generator.

[0015] The transmitter further comprises two electronic switches connected in series and switched on alternately according to the alternation of high and low sections of a pulse signal generated by the pulse generator; a capacitor, one end of which is connected to the serial connection point of the two electronic switches; and an inductor, one end of which is connected to the other end of the capacitor, and the high-frequency current can be generated by utilizing the resonance phenomenon between the capacitor and the inductor.

[0016] The above transmitter further includes a DC generating unit that generates a DC having a voltage that varies according to the number of the plurality of solar panels from a portion of the output power of the inverter and outputs the generated DC through a positive terminal and a negative terminal, wherein the positive terminal of the DC generating unit is connected to one end of one of the two electronic switches and the negative terminal of the DC generating unit is connected to one end of the other of the two electronic switches and the other end of the inductor, so that a resonance phenomenon may occur between the capacitor and the inductor due to the DC generated by the DC generating unit.

[0017] The above transmitter further includes a magnetic core formed in a ring shape having a hollow, wherein a part of the ring shape is arranged to pass through the inside of the coil of the inductor, and a part of the connecting line is arranged to pass through the hollow of the magnetic core, so that a high-frequency current can be induced in the connecting line by a high-frequency current generated in the inductor due to a resonance phenomenon between the capacitor and the inductor.

[0018] According to another aspect of the present invention, a photovoltaic power generation system including the rapid cutoff device is provided.

[0019] A rapid cutoff device with a two-terminal structure for each solar panel can be provided by a transmitter that generates a high-frequency current and transmits it through a connecting line that electrically connects multiple solar panels, and multiple receivers that switch the electrical connection between the two terminals using the power of the high-frequency current flowing through the connecting line, with each of the two terminals connected between two adjacent solar panels. As such, since a rapid cutoff device with a two-terminal structure for each solar panel can be provided, the number of contacts per solar panel can be reduced to two compared to a conventional four-terminal rapid cutoff device.

[0020] As a result, compared to conventional 4-terminal rapid disconnectors, the installation process of the rapid disconnector can be simplified, and the wiring used to connect solar panels during the installation process is reduced, leading to lower installation and maintenance costs. In particular, since there is no increase in wiring used to connect solar panels during the installation process, the problem of reduced efficiency in existing solar power generation systems caused by the installation of the rapid disconnector does not occur. Furthermore, as the number of contacts per solar panel is minimized, the possibility of arc generation can be significantly reduced.

[0021] The effects are not limited to those described above, and other effects may be derived from the following description.

[0022] FIG. 1 is a configuration diagram of a photovoltaic power generation system according to one embodiment of the present invention.

[0023] Figure 2 is a circuit diagram of each receiver (53) shown in Figure 1.

[0024] Figure 3 is a waveform diagram of various currents flowing through the circuit of each receiver (53) shown in Figure 2.

[0025] Figure 4 is a circuit diagram of the transmitter (51) shown in Figure 1.

[0026] Figure 5 is an equivalent circuit diagram of the LC resonant part of the circuit of the transmitter (51) shown in Figure 4.

[0027] FIG. 6 is a diagram illustrating the rapid blocking process according to the state of the connecting line (40) shown in FIG. 1.

[0028] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The embodiments of the present invention described below relate to a rapid cutoff device with a two-terminal structure capable of rapidly cutting off the electrical connection between two adjacent solar panels using only two terminals for each solar panel, and a solar power generation system including the rapid cutoff device with a two-terminal structure. Hereinafter, such a device and system will be briefly referred to as a "rapid cutoff device" and a "solar power generation system."

[0029] FIG. 1 is a configuration diagram of a photovoltaic power generation system according to an embodiment of the present invention. Referring to FIG. 1, the photovoltaic power generation system according to the present embodiment is composed of a plurality of photovoltaic panels (10), a plurality of junction boxes (20), an inverter (30), a connecting line (40), and a rapid disconnection device (50). FIG. 1 illustrates the essential components of the present embodiment so that the present embodiment can be easily understood without obscuring the features of the present embodiment. A person skilled in the art to which the present embodiment belongs will understand that, in addition to the components shown in FIG. 1, other components, such as a distribution board and a circuit breaker, may be added.

[0030] Each of the multiple solar panels (10) produces direct current power from sunlight by converting solar energy into electrical energy. Each solar panel (10) consists of a flat panel, multiple solar cells attached to the panel, and components for electrically connecting the multiple solar cells. The multiple solar cells are connected in series after being connected in units of a certain number, or connected in parallel after being connected in series in units of a certain number.

[0031] Each of the multiple junction boxes (20) is installed on each solar panel (10) and connected to the multiple output lines of each solar panel (10), and serves to output DC power produced by each solar panel (10) to the outside through its two terminals. In this embodiment, the two terminals of each junction box (20) serve as connection points between each solar panel (10) and each receiver (53) of the rapid cutoff device (50).

[0032] The inverter (30) converts direct current power produced by a plurality of solar panels (10) into alternating current power. The inverter (30) has two input terminals for receiving direct current power produced by a plurality of solar panels (10) and two output terminals for supplying alternating current power to the outside. The inverter (30) converts the direct current power input from the plurality of solar panels (10) into alternating current power through its two input terminals, and outputs the alternating current power thus converted through its two output terminals.

[0033] The connecting line (40) serves to connect multiple solar panels (10) in series by connecting multiple junction boxes (20) installed on multiple solar panels (10) in series. The connecting line (40) consists of multiple wires placed between each of two adjacent solar panels (10), a wire placed between one of the two solar panels (10) placed at the outermost position in the series connection structure of multiple solar panels (10) and one of the two input terminals of the inverter (30), and a wire placed between the other solar panel (10) placed at the outermost position in the series connection structure of multiple solar panels (10) and the other of the two input terminals of the inverter (30).

[0034] Each of the multiple wires positioned between two adjacent solar panels (10) is connected between the positive terminal of one of the two junction boxes (20) installed on the adjacent solar panels (10) and the negative terminal of the other junction box (20). The wire positioned between one of the two outermost solar panels (10) and one terminal of the inverter (30) is connected between the positive terminal of the junction box (20) installed on the solar panel (10) and one terminal of the inverter (30). The wire positioned between the other of the two outermost solar panels (10) and another terminal of the inverter (30) is connected between the negative terminal of the junction box (20) installed on the solar panel (10) and another terminal of the inverter (30).

[0035] Referring to FIG. 1, the rapid blocking device (50) according to the present embodiment is composed of a transmitter (51), a manual blocker (52), and a plurality of receivers (53). As shown in FIG. 1, the transmitter (51) is installed inside the housing of the inverter (30), and the manual blocker (52) is installed outside the housing of the inverter (30). Each of the multiple receivers (53) is inserted in series into a connecting line (40) that is placed between two adjacent solar panels (10) of the multiple solar panels (10), so that one of the two terminals (530) of each receiver (53) is connected to the positive terminal of one of the two adjacent solar panels (10) through the connecting line (40), and the other of the two terminals (530) of each receiver (53) is connected to the negative terminal of the other of the two adjacent solar panels (10) through the connecting line (40).

[0036] As described above, a plurality of solar panels (10) are connected in series by a connecting line (40) that connects a plurality of junction boxes (20) installed on the plurality of solar panels (10) in series. The positive terminal of a solar panel (10) connected to one of the two terminals (530) of each receiver (53) refers to the positive terminal of the junction box (20) installed on the solar panel (10), and the negative terminal of a solar panel (10) connected to the other of the two terminals (530) of each receiver (53) refers to the negative terminal of the junction box (20) installed on the solar panel (10). In the connecting line (40) of this embodiment, direct current output from the plurality of solar panels (10) connected in series and high-frequency current transmitted by the transmitter (51) flow.

[0037] A plurality of receivers (53) receive a high-frequency current flowing through a connecting line (40) in a state where each of the two terminals (530) is connected between two adjacent solar panels (10), and switches the electrical connection between two adjacent solar panels (10) by using the power of the high-frequency current received in this way. When high-frequency current flows through the connecting line (40), the electrical connection between the two terminals (530) of each receiver (53) is turned on, thereby turning on the electrical connection between two adjacent solar panels (10) connected to the two terminals (530) of each receiver (53), and when high-frequency current does not flow through the connecting line (40), the electrical connection between the two terminals (530) of each receiver (53) is turned off, thereby turning off the electrical connection between two adjacent solar panels (10) connected to the two terminals (530) of each receiver (53).

[0038] FIG. 2 is a circuit diagram of each receiver (53) shown in FIG. 1. Referring to FIG. 2, each receiver (53) is composed of a high-frequency detector (531), a MOSFET (532), a control signal generator (533), and a capacitor (534). As described above, each receiver (53) receives a high-frequency current flowing through a connecting line (40) and functions to switch the electrical connection between two adjacent solar panels (10) by using the power of the high-frequency current received in this way to switch the electrical connection between two terminals (530). This function can be implemented by the high-frequency detector (531), the MOSFET (532), the control signal generator (533), and the capacitor (534).

[0039] The high-frequency detection unit (531) receives the high-frequency current flowing in the connecting line (40) by detecting the high-frequency current from the change in the magnetic field around the connecting line (40) caused by the high-frequency current flowing in the connecting line (40). The high-frequency detection unit (531) is composed of a magnetic core (5311) and a wire (5312). The magnetic core (5311) is formed in a ring shape having a hollow and serves to focus the magnetic field generated from the current flowing in the connecting line (40) which is arranged to pass through the hollow. The wire (5312) detects the high-frequency current among the current flowing in the connecting line (40) by winding the magnetic core (5311) multiple times in a manner that passes through the hollow of the magnetic core (5311) and then passes through the hollow of the magnetic core (5311) again.

[0040] The frequency band of the high-frequency current detected by the wire (5312) is determined by various factors such as the permeability, cross-sectional area, average perimeter of the magnetic core (5311), and the number of turns of the wire (5312) around the magnetic core (5311). For example, the frequency band of the high-frequency current detected by the wire (5312) is inversely proportional to the number of turns of the wire (5312) around the magnetic core (5311). Depending on the frequency band of the high-frequency current flowing in the connecting line (40), the number of turns of the wire (5312) around the magnetic core (5311) needs to be appropriately designed.

[0041] As illustrated in FIG. 2, the high-frequency detector (531) detects the high-frequency current "I" flowing in the connecting line (40). ac1 High-frequency current "I from the change in magnetic field around the connecting line (40) caused by " ac2 Detect ", and the high-frequency current "I" detected in this way ac2 High-frequency current "I" flowing through the connecting line (40) in the form of " ac1 "Receives the high-frequency current "I" detected by the high-frequency detector (531). ac2 The magnitude of "I" is the high-frequency current "I" flowing in the connecting line (40) according to the following mathematical formula 1. ac1 It is determined by the size of " and the number of turns of the wire (5312) for the magnetic core (5311), "N". That is, the high-frequency current "I" detected by the high-frequency detector (531). ac2 The magnitude of "I" is the high-frequency current flowing in the connecting line (40). ac1 It is proportional to the size of the wire (5312) and inversely proportional to the number of turns "N" of the wire (5312) around the magnetic core (5311).

[0042]

[0043] A MOSFET (532) is installed between the two terminals (530) of each receiver (53) and switches the electrical connection of the two terminals (530) of each receiver (53) using the power of the high-frequency current detected by the high-frequency detector (531), thereby switching the electrical connection between the positive terminal of one of the two adjacent solar panels (10) connected through each receiver (53) and the negative terminal of the other of the two adjacent solar panels (10). The MOSFET (532) of this embodiment is an N-type MOSFET in which a current flow is formed between the drain terminal "D" and the source terminal "S" when the voltage of the gate terminal "G" is higher than the voltage of the source terminal "S".

[0044] The control signal generation unit (533) generates a control signal to control the switching operation of the MOSFET (532) by rectifying the high-frequency current detected by the high-frequency detection unit (531) and transforming it to a voltage greater than the threshold voltage of the MOSFET (532). The control signal generation unit (533) can be implemented as a combination of a rectifier for rectifying the high-frequency current detected by the high-frequency detection unit (531), a charging capacitor that is charged by the DC output from the rectifier, and a converter that generates a control signal by transforming the charging voltage of the charging capacitor.

[0045] As illustrated in FIG. 2, a control signal "V" for controlling the switching operation of the MOSFET (532) GS " is a signal output from the control signal generation unit (533) and has a voltage greater than the threshold voltage of the MOSFET (532). High-frequency current "I" in the connection line (40). ac1 When " is flowing, a control signal "V" is received from the control signal generation unit (533). GS " is output, and the voltage between the gate terminal "G" and the source terminal "S" of the MOSFET (532) becomes greater than the threshold voltage. High-frequency current "I" in the connection line (40). ac1When the current does not flow, no signal is output from the control signal generation unit (533), and no current flow is formed between the gate terminal "G" and the source terminal "S" of the MOSFET (532).

[0046] The drain terminal "D" of the MOSFET (532) is connected to one of the two terminals (530) of each receiver (53), and the source terminal "S" of the MOSFET (532) is connected to the other of the two terminals (530) of each receiver (53). In this state, a control signal generated by the control signal generating unit (533) is input to the gate terminal "G" of the MOSFET (532). When the voltage of the control signal input to the gate terminal "G" of the MOSFET (532) is less than the threshold voltage, the electrical connection between the two terminals (530) of each receiver (53) is turned off, and when the voltage of the control signal input to the gate terminal "G" of the MOSFET (532) is greater than or equal to the threshold voltage, the electrical connection between the two terminals (530) of each receiver (53) is turned on.

[0047] The capacitor (534) is connected between the drain terminal "D" and the source terminal "S" of the MOSFET (532). Among the DC and high-frequency currents flowing in the connection line (40), the DC current passes between the drain terminal "D" and the source terminal "S" and flows between the two terminals when the voltage of the control signal input to the gate terminal of the MOSFET (532) is greater than or equal to the threshold voltage of the MOSFET (532). Among the DC and high-frequency currents flowing in the connection line (40), the high-frequency current passes through the capacitor (534) and flows between the two terminals. In this way, the capacitor (534) serves to allow the high-frequency current transmitted by the transmitter (51) to flow in the connection line (40) regardless of whether DC current flows in the connection line (40). Therefore, regardless of whether there is a DC current flow in the connecting line (40), the electrical connection between the two terminals (530) of each receiver (53) can be turned on or off by whether the transmitter (51) transmits a high-frequency current.

[0048] FIG. 3 is a waveform diagram of various currents flowing through the circuit of each receiver (53) shown in FIG. 2. "I shown in FIG. 3 dc + I ac1 " represents the waveform of the current flowing through the connecting line (40), and "I ac2 " represents the waveform of the current detected by the high-frequency detector (531), and "V cc " represents the voltage waveform of the charging power of the control signal generation unit (533), and "V GS " indicates the voltage waveform of the control signal from the control signal generation unit (533). When the operation of the rapid cutoff device (50) of this embodiment begins, a high-frequency current is transmitted by the transmitter (51), and "I dc + I ac1 As shown in the waveform, the connecting line (40) has a high-frequency current "I ac1 Only [something] flows.

[0049] High-frequency current "I" in the connecting line (40) ac1 While "it flows, "I ac2 As shown in the waveform, the high-frequency detector (531) detects the high-frequency current "I ac2 " is detected, and high-frequency current "I ac2 " is fed into the control signal generation unit (533). "V cc As shown in the waveform, high-frequency current "I ac2 As " is introduced into the control signal generation unit (533), the charging of the control signal generation unit (533) proceeds. When the charging of the control signal generation unit (533) proceeds to the extent that it can generate a control signal having a voltage greater than or equal to the threshold voltage of the MOSFET (532), "V GS As shown in the waveform, the control signal generation unit (533) generates and outputs a control signal. Subsequently, a voltage greater than the threshold voltage of the MOSFET (532) is applied between the gate terminal "G" and the source terminal "S" of the MOSFET (532), thereby converting the electrical connection between the two terminals (530) of each receiver (53) from the off state to the on state.

[0050] The transmitter (51) generates a high-frequency current using a portion of the power produced by a plurality of solar panels (10), and transmits the high-frequency current generated using a portion of the power produced by the plurality of solar panels (10) through the connecting line (40) so that the high-frequency current generated in this way flows through the connecting line (40) that electrically connects the plurality of solar panels (10). The transmitter (51) generates a high-frequency current using a portion of the output power of an inverter (30) that receives the direct current generated from the plurality of solar panels (10) through the connecting line (40) and converts it into alternating current.

[0051] At the moment the operation of the rapid cutoff device (50) of this embodiment begins, the electrical connection between the two terminals (530) of each receiver (53) inserted in series in the connecting line (40) arranged between each of the two adjacent solar panels (10) is off, so the inverter (30) cannot receive direct current generated from the plurality of solar panels (10). At the moment the operation of the rapid cutoff device (50) of this embodiment begins, the transmitter (51) generates high-frequency current using an external power source, such as a separate battery power source or commercial power source, until the electrical connection between the two terminals (530) of each receiver (53) is turned on.

[0052] After the electrical connection between the two terminals (530) of each receiver (53) is turned on, when the power output of the inverter (40) is cut off, the electrical connection between the two terminals (530) of each receiver (53), which are inserted in series into the connecting line (40) placed between each of the two adjacent solar panels (10), is turned off. In this way, when the power output of the inverter (40) is cut off due to various causes, the electrical connection between each of the two adjacent solar panels (10) is automatically disconnected. This prevents electric shock accidents caused by the power generation of the solar panels (10) during maintenance work on the power output cutoff of the inverter (40).

[0053] FIG. 4 is a circuit diagram of the transmitter (51) shown in FIG. 1. Referring to FIG. 4, the transmitter (51) is composed of a pulse generator (511), a DC generating unit (512), two electronic switches (5131, 5132), a capacitor (514), an inductor (515), and a magnetic core (516).

[0054] The pulse generator (511) generates a pulse signal in which high and low sections alternate. The high-frequency current flowing through the connecting line (40) takes the form of alternating current in which the direction of current flow is periodically reversed according to the alternating high and low sections of the pulse signal generated by the pulse generator (511). The pulse generator (511) generates a pulse signal using the direct current generated by the direct current generation unit (512). For example, the pulse generator (511) can generate a pulse signal having a duty cycle of 50% of a constant frequency "f" that is preset by the user.

[0055] The DC generation unit (512) generates a DC current having a voltage that varies according to the number of solar panels (10) from a portion of the output power of the inverter (40), and outputs the DC current thus generated through its positive and negative terminals. At the moment when the operation of the rapid cutoff device (50) of this embodiment begins, the DC generation unit (512) generates a DC current using an external power source, such as a separate battery power source or commercial power source, until the electrical connection between the two terminals (530) of each receiver (53) is turned on. As the number of solar panels (10) increases, the number of receivers (53) also increases, and the amount of power required for the operation of multiple receivers (53) also increases. The voltage of the DC current generated by the DC generation unit (512) is set by the user according to the number of solar panels (10).

[0056] Two electronic switches (5131, 5132) are connected in series with each other and are switched on alternately according to the alternation of the high and low sections of the pulse signal generated by the pulse generator (511). The two electronic switches (5131, 5132) can be implemented with two MOSFETs. One end of the capacitor (514) is connected to the serial connection point of the two electronic switches (5131, 5132), and the other end is connected to one end of the inductor (515). One end of the inductor (515) is connected to the other end of the capacitor (514), and the other end is connected to the negative terminal of the DC generating unit (512). The positive terminal of the DC generating unit (512) is connected to one end of one of the two electronic switches (5131, 5132), and the negative terminal is connected to one end of the other electronic switch (5132) of the two electronic switches (5131, 5132) and the other end of the inductor (515). In this way, by connecting the DC generating unit (512), the two electronic switches (5131, 5132), the capacitor (514), and the inductor (515), a resonance phenomenon occurs between the capacitor (514) and the inductor (515) by the DC generated from the DC generating unit (512).

[0057] FIG. 5 is an equivalent circuit diagram of the LC resonance portion of the circuit of the transmitter (51) shown in FIG. 4. In FIG. 5, "C" represents the capacitor (514) shown in FIG. 4, and "L" represents the inductor (515) shown in FIG. 4. When two electronic switches (5131, 5132) are switched by a pulse signal generated by a pulse generator (511), a square wave signal is input to one end of the capacitor (514). The square wave signal input to one end of the capacitor (514) can be expressed as a Fourier series and consists of a fundamental frequency component and infinitely many harmonic components. The fundamental frequency component "V" of the signal input to one end of the capacitor (514) dcp It can be expressed by the following mathematical formula 2.

[0058]

[0059] In mathematical equation 2, "V dc " represents the DC voltage generated by the DC generation unit (512), and the angular frequency "ω" can be expressed as 2πf, where f is the frequency of the pulse signal generated by the pulse generator (511). The capacitance value of the capacitor (514) and the inductance value of the inductor (515) need to be appropriately designed so that the frequency "f" of the pulse signal generated by the pulse generator (511) can become the resonance frequency between the capacitor (514) and the inductor (515).

[0060] In FIG. 5, "R" represents the resistance of the load and signifies the load resistance of the LC resonant circuit, including the total resistance of a plurality of transmitters (51). The current "I" flowing through the load of the LC resonant circuit. act " can be expressed by the following mathematical equation 3. In a series LC resonant circuit as shown in FIG. 5, the impedance of the LC resonant circuit is minimized at the resonant frequency, so the magnitude of the current can be maximized.

[0061]

[0062] The magnetic core (516) is formed in a ring shape having a hollow, and a part of the ring shape is positioned to pass through the inside of the coil of the inductor (515). A part of the connecting line (40) is positioned to pass through the hollow of the magnetic core (516), thereby allowing the high-frequency current "I" generated in the inductor (515) due to the resonance phenomenon between the capacitor (514) and the inductor (515) to pass through the hollow of the magnetic core (516). act High-frequency current "I" in the connecting line (40) by " ac1 " is induced. In this way, the high-frequency current "I flowing in the connecting line (40) ac1 " is generated by utilizing the resonance phenomenon between the capacitor (514) and the inductor (515).

[0063] FIG. 6 is a diagram illustrating the rapid disconnection process according to the state of the connecting line (40) shown in FIG. 1. To aid in understanding the present embodiment, FIG. 6 shows the magnetic core (516) of the transmitter (51) and the magnetic core (5311) of the receiver (53) exposed to the outside of the transmitter (51) and the outside of the receiver (53). FIG. 6 (a) shows the entire connecting line (40) in a normally connected state, and FIG. 6 (b) shows the connecting line (40) in a state where a part of it is severed due to various disaster situations such as fire or landslide.

[0064] As shown in FIG. 6(a), when the entire connecting line (40) is normally connected, a high-frequency current "I" passes through the connecting line (40). ac1 "The current flows normally, and the electrical connection between the two terminals (530) of each receiver (53) inserted in series in the connecting line (40) arranged between each of the two adjacent solar panels (10) is turned on. In this case, the inverter (30) receives the direct current generated by the power generation of the multiple solar panels (10). As shown in FIG. 6 (b), when a part of the connecting line (40) is disconnected, the high-frequency current "I" through the connecting line (40) ac1 When the current is no longer flowing and part of the connecting line (40) is severed, the electrical connection between the two terminals (530) of each receiver (53) is turned off. In this case, only the output voltage of each solar panel remains, thereby preventing electric shock accidents during the maintenance process of the worker.

[0065] A manual circuit breaker (52) is installed on a line to which the driving power of the DC generating unit (512) of the transmitter (51) is input, or is installed on a connecting line (40), and a high-frequency current "I" is transmitted through the connecting line (40) according to user operation. ac1It serves to allow or block the flow of electricity. By operating the manual circuit breaker (52), the user can turn off the electrical connection between two adjacent solar panels (10) when necessary, such as for maintenance work on the solar power generation system.

[0066] The present invention has been described above with reference to its preferred embodiments. Those skilled in the art will understand that the present invention may be embodied in modified forms without departing from the essential characteristics of the invention. Therefore, the disclosed embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the invention is defined by the claims, not by the foregoing description, and all variations within the scope of the claims should be interpreted as being included in the invention.

Claims

1. A transmitter that generates a high-frequency current and transmits the generated high-frequency current through a connecting line so that the generated high-frequency current flows through a connecting line that electrically connects the plurality of solar panels; and It includes a plurality of receivers, each having two terminals connected between two adjacent solar panels of the plurality of solar panels, receiving a high-frequency current flowing through the connecting line, and switching the electrical connection between the two terminals using the power of the received high-frequency current to switch the electrical connection between the two adjacent solar panels. A rapid cutoff device characterized by turning on the electrical connection between the two terminals when a high-frequency current flows through the connecting line, thereby turning on the electrical connection between the two adjacent solar panels, and turning off the electrical connection between the two adjacent solar panels when a high-frequency current does not flow through the connecting line, thereby turning off the electrical connection between the two terminals.

2. In Paragraph 1, The plurality of solar panels are connected in series with each other by the connecting line, and each receiver is inserted in series into the connecting line portion disposed between each of the two adjacent solar panels, so that one of the two terminals of each receiver is connected to the positive terminal of one of the two adjacent solar panels through the connecting line, and the other of the two terminals of each receiver is connected to the negative terminal of the other of the two adjacent solar panels through the connecting line. A rapid cutoff device characterized by the fact that a direct current output from the plurality of solar panels and a high-frequency current transmitted by the transmitter flow through the above connecting line.

3. In Paragraph 2, A rapid cutoff device characterized by each receiver including a MOSFET installed between the two terminals of each receiver and switching the electrical connection between the positive terminal of one solar panel and the negative terminal of another solar panel by switching the electrical connection between the two terminals of each receiver using the power of the received high-frequency current.

4. In Paragraph 3, Each of the above receivers further includes a high-frequency detector that receives the high-frequency current flowing in the connection line by detecting the high-frequency current flowing in the connection line from a change in the magnetic field around the connection line caused by the high-frequency current flowing in the connection line. A rapid cutoff device characterized by the above MOSFET switching the electrical connection between the two terminals using the power of the high-frequency current detected by the high-frequency detector.

5. In Paragraph 4, The above high-frequency detector A magnetic core formed in a ring shape having a hollow and arranged to focus a magnetic field generated from a current flowing through the connecting line arranged to pass through the hollow; and It includes a wire that detects the high-frequency current among the currents flowing in the connecting line by winding the magnetic core multiple times in a manner that passes through the hollow of the magnetic core and then passes through the hollow of the magnetic core again. A rapid interruption device characterized in that the frequency band of the high-frequency current detected by the above-mentioned wire is determined by the number of turns of the wire around the above-mentioned magnetic core.

6. In Paragraph 4, Each of the above receivers further includes a control signal generation unit that generates a control signal for controlling the switching operation of the MOSFET by rectifying and transforming the high-frequency current detected by the high-frequency detection unit. With the drain terminal of the MOSFET connected to one of the two terminals of each receiver and the source terminal of the MOSFET connected to the other of the two terminals of each receiver, a control signal generated by the control signal generation unit is input to the gate terminal of the MOSFET, A rapid cutoff device characterized by the fact that when the voltage of a control signal input to the gate terminal of the MOSFET is less than the threshold voltage of the MOSFET, the electrical connection between the two terminals of each receiver is turned off, and when the voltage of a control signal input to the gate terminal of the MOSFET is greater than or equal to the threshold voltage of the MOSFET, the electrical connection between the two terminals of each receiver is turned on.

7. In Paragraph 4, Each of the above receivers further includes a capacitor connected between the drain terminal and the source terminal of the MOSFET, and Among the direct current and high-frequency current flowing in the above connecting line, the direct current passes between the drain terminal and the source terminal of the MOSFET and flows between the two terminals when the voltage of the control signal input to the gate terminal of the MOSFET is greater than or equal to the threshold voltage of the MOSFET, and A rapid interruption device characterized in that, among the direct current and high-frequency current flowing in the above-mentioned connecting line, the high-frequency current passes through the above-mentioned capacitor and flows between the above-mentioned two terminals.

8. In Paragraph 2, The above transmitter generates the high-frequency current by utilizing a portion of the output power of an inverter that receives direct current generated by the power generation of the plurality of solar panels through the connecting line and converts it into alternating current, and A rapid cutoff device characterized by the electrical connection between two terminals of each receiver inserted in series in a connecting line portion disposed between each of the two adjacent solar panels being turned off when the power output of the above inverter is cut off.

9. In Paragraph 8, The above transmitter includes a pulse generator that generates a pulse signal in which high and low sections alternate, and A rapid interruption device characterized in that the above high-frequency current has the form of alternating current in which the direction of current flow is periodically reversed according to the alternation of high and low sections of the pulse signal generated by the pulse generator.

10. In Paragraph 9, The above transmitter Two electronic switches connected in series with each other and switched on alternately according to the alternation of the high and low sections of the pulse signal generated by the pulse generator; A capacitor connected at one end to the series connection point of the two electronic switches above; and One end further includes an inductor connected to the other end of the above capacitor, and A rapid cutoff device characterized by the fact that the above high-frequency current is generated by utilizing the resonance phenomenon between the capacitor and the inductor.

11. In Paragraph 10, The transmitter further includes a DC generation unit that generates a DC having a voltage that varies according to the number of the plurality of solar panels from a portion of the output power of the inverter, and outputs the generated DC through a positive terminal and a negative terminal. A rapid cutoff device characterized in that the positive terminal of the DC generating unit is connected to one end of one of the two electronic switches, and the negative terminal of the DC generating unit is connected to one end of the other of the two electronic switches and the other end of the inductor, thereby causing a resonance phenomenon between the capacitor and the inductor by the DC generated by the DC generating unit.

12. In Paragraph 11, The above transmitter further includes a magnetic core formed in a ring shape having a hollow structure, wherein a portion of the ring shape is arranged to pass through the inside of the coil of the inductor. A rapid cutoff device characterized in that a portion of the above connecting line is arranged to pass through the hollow of the above magnetic core, thereby inducing the high-frequency current in the above connecting line by the high-frequency current generated in the inductor due to the resonance phenomenon between the capacitor and the inductor.

13. A photovoltaic power generation system including the rapid shutdown device of claim 1.

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