KR20190044791A - Connection board of solar power generation apparatus with enhanced monitoring functions - Google Patents

Abstract

Provided is a connection board of a solar power generation apparatus, comprising: an input terminal receiving power generated at a solar ray panel; an output terminal outputting the power received by the input terminal toward an inverter; a cutoff device; a backward flow prevention diode; a bypass line forming a bypass path not passing the backward flow prevention diode; a bypass switch installed on the bypass line; a first measurement unit measuring at least one electrical physical quantity among voltage, current and power at an output end of the input terminal; a second measurement unit installed between a contact point of the backward flow prevention line and the bypass line and an input side of the output terminal to measure at least one second electrical physical quantity among voltage, current and power at a corresponding installation position; and a control unit determining whether the bypass switch gets opened or closed based on a ratio between the first electrical physical quantity measured by the first measurement unit and the second electrical physical quantity measured by the second measurement unit in the case that the first electrical physical quantity measured by the first measurement unit deviates from an electrical physical quantity within a preset normal range.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a photovoltaic power generation apparatus,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar power generation apparatus, and more particularly, to a connection panel of a solar power generation apparatus having an enhanced monitoring function.

Generally, the solar cell connecting unit collects the direct current generated from a plurality of solar cell modules included in the solar power generation system and outputs the collected direct current to the inverter included in the solar power generation system. Such a photovoltaic connection panel generally includes an input terminal, a fuse, a diode, and an output terminal, and the diode functions to shut off a current flowing in a reverse direction.

Referring to FIG. 1, a technology implementation method of Korean Patent No. 10-1550011 (published on Sep. 4, 2015) as a prior patent document related to the related art will be described with reference to FIG. 1. A plurality of solar cells A plurality of fuses S3 (hereinafter referred to as a breaker), a plurality of diodes S4 and an output terminal S5 for collecting the power output from the plurality of diodes into one, , A plurality of bypass circuits (100) for bypassing the power input from the plurality of fuses (S3) and the circuit breakers to the plurality of diodes (S4) and outputting them to the output terminal (S5); A plurality of bypass switches 110 for opening and closing the bypass circuit 100 in accordance with a control signal of the control unit 130 and a measurement unit 120 for monitoring the state of the power value flowing in the circuit 200. [ .

At this time, the control unit 130 of the connection unit determines the state of the circuit 200 by the measurement unit 120 and opens / closes the bypass switch 110 so that the power input to the input terminal S2 (120) in any one of the groups in which power is normally and uniformly generated in each of the plurality of groups while being simultaneously input to the plurality of bypass switches (110) It is determined that a reverse current flows in the circuit direction in which the normally generated power flows abnormally, and the bypass switch 110 is turned off to block the reverse current by the diode .

Also, when the measured power value through the measurement unit 120 is within the predetermined voltage range, the control unit 130 of the connection unit determines that the normal power generation is performed and turns the bypass switch 110 ON, And is output to the output terminal S5 via the bypass circuit 100. [

However, according to the prior art described above, the power generation state of the PV (photovoltaic) panel is determined only by the measurement result of the measurement unit 120 that measures the circuit 200 on the input terminal side of the connection panel, It is possible to directly estimate the backflow occurrence condition in which the reverse current occurs when the voltage range is out of range. In other words, although the prior art is simple in terms of the circuit configuration, since it determines the state of the backflow only by the measurement result of only one measurement point (circuit on the connection half input terminal side), a more sophisticated judgment process Is absent.

Accordingly, there is a need for a new method for more precisely determining whether backwashing occurs in accordance with the state of photovoltaic power generation, and finely controlling the control accordingly. There is also a need for a fire prevention method in a connection device that reflects such a sophisticated determination result.

SUMMARY OF THE INVENTION The present invention is to provide a connection unit of a photovoltaic power generation apparatus having an enhanced monitoring function.

The present invention also provides a connection device capable of preventing a fire that may occur in a connection device of a solar power generation device.

According to an aspect of the present invention, there is provided a solar panel comprising: an input terminal for receiving power produced in a solar panel; An output terminal for outputting the power inputted through the input terminal to the inverter side; A breaker connected to an output side of the input terminal; A reverse current prevention diode connected to an output side of the circuit breaker and an input side of the output terminal; A bypass line connected to an output side of the circuit breaker and an input side of the output terminal, the bypass line being provided in parallel with the backflow preventing line through the backflow preventing diode to form a bypass path that does not pass through the backflow preventing diode; A detour switch provided on the bypass line; And a control section for generating an open / close control signal for controlling opening and closing of the detour switch.

The connection unit may include a first measurement unit installed at an output terminal of the input terminal and measuring a first electrical physical quantity of at least one of voltage, current, and electric power at an output terminal of the input terminal; And a second measuring unit provided between the contact point of the backflow preventing line and the bypass line and the input side of the output terminal and measuring at least one second electrical physical quantity of voltage, .

In this case, the control unit may be configured to determine whether the first electrical physical quantity measured by the first measuring unit is outside the normal electrical energy value within a normal range determined in advance to determine that the power generation by the solar panel is a normal power production state Based on the ratio between the first electrical physical quantity measured by the first measuring unit and the second electrical physical quantity measured by the second measuring unit and having the same property as the first electrical physical quantity, And determines whether to open or close.

According to the embodiments of the present invention, it is possible to provide a connection unit of a solar power generation apparatus having an enhanced monitoring function and to prevent a fire that may occur in the connection unit.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view schematically showing a general configuration of a connection unit of a photovoltaic generator; Fig.
2 is a schematic view of an overall system for explaining a connection panel of a photovoltaic device having an enhanced monitoring function according to an embodiment of the present invention;
3 is a block diagram separately showing functional blocks in a connection module for implementing an enhanced monitoring function according to an embodiment of the present invention;
FIG. 4 and FIG. 5 are flowcharts showing a monitoring function executed in a connection module according to an embodiment of the present invention and a control flow therefor. FIG.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. In addition, numerals (e.g., first, second, etc.) used in the description of the present invention are merely an identifier for distinguishing one component from another.

Also, throughout the specification, when an element is referred to as being " connected " or " connected " with another element, the element may be directly connected or directly connected to the other element, It should be understood that, unless an opposite description is present, it may be connected or connected via another element in the middle.

Also, throughout the specification, when an element is referred to as " including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise. Also, the terms " a ", " module ", and the like in the description mean a unit for processing at least one function or operation, which means that it can be implemented by one or more hardware or software or a combination of hardware and software .

FIG. 2 is a schematic diagram of an overall system for explaining a connection panel of a photovoltaic power generation apparatus having an enhanced monitoring function according to an embodiment of the present invention. 4 and 5 are flowcharts showing a monitoring function and a control flow performed in the connection module according to the embodiment of the present invention. Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings attached to FIG. 2 to FIG.

Generally, as shown in Fig. 2, a photovoltaic power generation apparatus includes a plurality of photovoltaic panels (PV_1, PV_2, ... PV_N in Fig. 2) and a DC (DC) AC) state to transmit the electric power in the direction of the system 300, a connection panel (not shown) for receiving the electric power generated from the plurality of solar panels by each string and communicating it to the inverter 200 side 100).

Thus, the connection block 100 includes a plurality of input terminals IN_1, IN_2, ... IN_N, a plurality of breakers fs1, fs2, ..., fsN (here, , The circuit breaker may be composed of a fuse assembly), a plurality of backflow prevention diodes D1, D2, ... DN and its backflow preventing lines 20, a plurality of bypass switches sw1, sw2, ... swN The bypass lines 10, and an output terminal OT for collecting the electric power transmitted through these lines, respectively.

In addition, a circuit breaker or a switch for interrupting the line may be additionally provided for each specific position in order to prevent abnormal power transmission throughout the system or to prevent the spread of generated fire or the like according to the system implementation method. (Cs1, cs2, ... csN) between the rear end of the backflow prevention line or bypass line and the output terminal (see cs1, cs2, ... csN), the output terminal rear end Switches may be added between the inverters (see ls1) and between the inverter and the grid (see ls2). However, it should be understood that this is merely illustrative of various positions in which the line disconnecting switch can be provided, and it is needless to say that it is not necessary to provide the line disconnecting switch at all of the specific positions exemplified above.

Hereinafter, a connection board 100 according to an embodiment of the present invention will be described in detail. In the course of describing it, for convenience and concentration of explanation, the power transmission path according to the first string of the connection half structure of FIG. 2 will be described.

Referring to FIG. 2, a connection board 100 according to an embodiment of the present invention includes an input terminal IN_1 for receiving power produced from a solar panel PV_1; An output terminal OT for outputting the power inputted through the input terminal to the inverter 200 side; A breaker (fs1) connected to an output side of the input terminal; A reverse current prevention diode (D1) connected to an output side of the circuit breaker and an input side of the output terminal; (20) connected in parallel to the output side of the circuit breaker and the input side of the output terminal, the reverse current prevention line (20) through the reverse current prevention diode (D1) A line 10; And a bypass switch sw1 provided on the bypass line.

2 and 3 together, the connection block 100 is provided at the output terminal of the input terminal (see position a1 in FIG. 2), and the voltage, current, and power at the output terminal of the input terminal A first measuring unit 110 for measuring a first electrical physical quantity of at least one of the first and second electric physical quantities; And a second electrical physical quantity of at least one of voltage, current and electric power at the mounting position (refer to position b1 in Fig. 2) provided between the contact point of the backflow preventing line and the bypass line and the input side of the output terminal A second measuring unit (120) for measuring the temperature; A third measuring unit 130 for detecting at least the temperature of the component inside the connection panel including the backflow prevention diode or whether an arc is generated; And a fire-fighting device for extinguishing a fire when a fire occurs in the connection box.

Here, various fire extinguishing devices may be used as the fire extinguishing device, but in this specification, the solid aerosol fire extinguisher 140 is used as shown in FIG. 3 as an example. Such a solid aerosol fire extinguisher can be miniaturized, its digestion system is environmentally friendly, and its life span is also longer than 15 years, so that it can be maintained as long as the life of the plant.

3, the connection block 100 is a functional block for connection control and fire prevention, and controls each switch provided at a specific position in accordance with the switch opening / closing control signal transmitted from the control unit 150 A communication controller 166 for reporting the monitoring status and the status of the inside of the connection panel to the external management device, A boosting unit 164, and the like.

With respect to the implementation methods of the monitoring of the solar power generation state, the monitoring of the inside of the connection panel, and the fire occurrence monitoring function through the connection board 100 according to the embodiment of the present invention including the above-mentioned configuration, 4 and FIG. 5, respectively. The state determination for each case in the contents to be described later can be performed by the determination unit 155 in the control unit 150. [

Case 1: normal power generation state

When the monitoring of the solar power generation state is started (refer to S110 in FIG. 4), the first measuring unit 110 calculates the electric physical quantity at the first point (see position a1 in FIG. 2) (Hereinafter referred to as a first electrical physical quantity) (refer to S120 in FIG. 4). Here, the first electrical physical quantity may be any one or two or more of voltage, current, and electric power at the corresponding position (as will be described later in the second electrical physical quantity), as described above.

According to the result of the measurement, the controller 150 determines that the first electrical physical quantity measured by the first measuring unit 110 is in a normal power production state by the solar panel PV_1, The power input from the photovoltaic panel PV_1 via the input terminal IN_1 is generated by the bypass line (power supply line) 10) to the output terminal OT side (refer to S130 and S140 in Fig. 4).

Here, the electrical physical quantity value within the normal range refers to, for example, an electrical physical quantity range converted from a statistical point of view based on an average power range in which a unit solar panel normally operates to perform a power generation operation Lt; / RTI >

In such a normal power generation state, there is no reverse flow from the path opposite to the normal power transmission path (that is, the reverse path from the grid to the solar panel direction), so that the bypass switch is turned on, So that the generated power is transmitted to the output terminal.

Second case: Bypass line connection status

Even if the electrical physical quantity measured at the first point as in the first case described above is within the normal range, a problem may arise in the connection half circuit configuration. For example, although the photovoltaic power generation state is normal, there may occur a contact failure or wiring on the power transmission path through the bypass line, and normal power transmission can not be performed in this case.

The control unit 150 in the connection block 100 according to the embodiment of the present invention is configured such that when the bypass switch sw1 is turned on according to the first case and the bypass line 10 is activated, The second electrical physical quantity measured at the second point (b1 position in FIG. 2) is compared with the first electrical physical quantity measured previously by the second electric physical quantity measuring unit 120. [

When it is determined that the ratio value between the first electrical physical quantity and the second electrical physical quantity is out of the predefined normal value range, it is determined that the connection has occurred on the power transmission path along the bypass line, Management apparatus (see S142, S144, and S148 in Fig. 4). On the other hand, if it is within the normal ratio value range, since no wiring or the like has occurred on the power transmission path, the output through the bypass line is maintained as it is (see S146 in FIG. 4).

Here, the pre-designated normal ratio value range is a range in which electric power is transmitted from the first point (a1) to the second point (b1) on the corresponding power transmission path, for example, (For example, in the range of the normal ratio value in the third case to be described later) in the range of the ratio between the electrical physical quantities that can be expected to occur when considering the factors of the voltage drop, The same can be applied).

Case 3: Quasi-steady state

Unlike the first case and the second case described above, when the first electrical physical quantity measured in step S130 of FIG. 4 is out of the electrical physical quantity value within the predetermined normal range, the controller 150 controls the detour switch (b1) measured by the second measuring unit 120 in a state where the first electrical physical quantity measured by the first measuring unit 120 is turned off.

Accordingly, when the ratio value between the first electrical physical quantity and the second electrical physical quantity is within the predetermined normal value range, the control unit 150 generates an on / off control signal for turning on the bypass switch sw1 , The power input from the solar panel PV_1 via the input terminal IN_1 is output to the output terminal OT through the bypass line 10 (see S150, S155, S160, and S165 in FIG. 5).

According to the existing prior art, if the first electrical physical quantity measured in step S130 of FIG. 4 deviates from the electrical physical quantity value within the predetermined normal range, it is presumed that the backflow is always generated, The path was switched to the direction of the backflow preventing line instead of the bypass line. However, according to this, there is a problem that a problem of heat generation by the diode frequently occurs because the diode is switched to the direction passing through the backflow prevention diode without asking whether the actual backflow occurs.

On the other hand, in the embodiment of the present invention, even when the first electrical physical quantity measured in step S130 in Fig. 4 deviates from the electrical physical quantity value within the predetermined normal range, the comparison with the electrical physical quantity measured at the second point It is possible to once again check whether actual backwash has occurred (or whether the backwash has occurred to such an extent that it can be accommodated by the entire system), and accordingly, the number of times of line switching in the direction of the backwash prevention line Can be minimized.

Case 4: Reverse flow path connection status

5, if the rate value falls within the predetermined range of the exception rate value (in this case, the bypass switch sw1 is turned off) It can be determined that the connection has occurred on the power transmission path according to the backflow prevention line 20 and the result of the connection determination can be reported to the external management apparatus (S170 and S530 in FIG. 5) S175).

Here, the pre-specified exception ratio value range is defined as a ratio value range between the first electrical physical quantity and the second electrical physical quantity, which may normally appear when a contact failure, wiring, or the like occurs on the power transmission path along the backflow- Lt; / RTI > For example, there is no problem in the electrical connection between the input terminal IN_1 and the circuit breaker fs1. However, if there is a problem in the electrical connection between the circuit breaker fs1 and the backflow prevention diode D1, . As described above, the ratio value range in the case where the ratio value shows a remarkable difference such that the ratio value can be displayed only in the electrically connected state may be set to the exception ratio value range.

Case 5: Backflow Occurrence State

In contrast to the fourth and fifth cases, in the relationship with the second electrical physical quantity measured by the second measuring unit 120 in a state where the detour switch sw1 is turned off, the first electrical physical quantity and the second electrical physical quantity If the ratio value between the second electrical physical quantities does not fall within the pre-specified exception ratio value range of step S170 of Fig. 5 as well as the pre-designated normal ratio value range of step S160 of Fig. 5, the power input via the input terminal IN_1 from the solar panel PV_1 is output to the output terminal OT through the backflow prevention line 20 by keeping the turn ON state of the switch SW1 S180 "

Case 6: Fire Hazard Status

In the case where the backflow prevention diode D1 is determined to be in the backflow state according to the fifth case described above, the backflow prevention diode D1 is subjected to the power transmission path of the backflow preventing line. And the like.

Therefore, in the fifth case described above, the control unit 150 determines whether or not an arc is generated, whether or not an arc is generated, and the like, based on the result of temperature measurement of the connection half internal part (in particular, the backflow prevention diode) received from the third measurement unit 130 Continuously monitor the detection results. Here, the third measuring unit 130 may include a temperature measuring sensor and / or an arc detecting sensor. The temperature measuring sensor may be a non-contact type sensor such as an IR sensor as well as a contact type sensor. An electromagnetic wave detecting sensor for detecting an electromagnetic wave caused by an arc may be used as the arc detecting sensor.

Accordingly, the control unit 150 continuously monitors the detection result of the third measuring unit, and when it is determined that a fire has occurred in the connection panel (that is, when the predetermined danger level of fire has been reached) Lt; RTI ID = 0.0 > a < / RTI > Accordingly, the fire prevention operation by the fire fighting device (solid aerosol fire extinguisher 140 in this example) can be performed.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the following claims And changes may be made without departing from the spirit and scope of the invention.

Claims (6)

As a connection unit of a photovoltaic power generation device,
An input terminal for receiving power produced by the solar panel; An output terminal for outputting the power inputted through the input terminal to the inverter side; A breaker connected to an output side of the input terminal; A reverse current prevention diode connected to an output side of the circuit breaker and an input side of the output terminal; A bypass line connected to an output side of the circuit breaker and an input side of the output terminal, the bypass line being provided in parallel with the backflow preventing line through the backflow preventing diode to form a bypass path that does not pass through the backflow preventing diode; A detour switch provided on the bypass line; And a control unit for generating an open / close control signal for controlling opening and closing of the detour switch,
A first measuring unit provided at an output terminal of the input terminal for measuring a first electrical physical quantity of at least one of voltage, current and electric power at an output terminal of the input terminal; And a second measuring unit provided between the contact point of the backflow preventing line and the bypass line and the input side of the output terminal and measuring at least one second electrical physical quantity of voltage, Further included,
When the first electrical physical quantity measured by the first measuring unit deviates from an electrical physical quantity value within a normal range determined in advance so as to determine that the power generation by the solar panel is a normal power production state, Based on a ratio between a first electrical physical quantity measured by the first measuring unit and a second electrical physical quantity measured by the second measuring unit and having the same property as the first electrical physical quantity, The connection unit of the photovoltaic device.
The method according to claim 1,
Wherein,
In a relationship with the second electrical physical quantity measured by the second measuring section in a state in which the detour switch is turned off when the measured first electrical physical quantity deviates from an electrical physical quantity value within the predetermined normal range, When the ratio value between the first electrical physical quantity and the second electrical physical quantity falls within a predetermined normal value range, an open / close control signal for turning on the bypass switch is generated, So that electric power is output to the output terminal side through the bypass line.
3. The method of claim 2,
Wherein,
In a relationship with the second electrical physical quantity measured by the second measuring section in a state in which the detour switch is turned off when the measured first electrical physical quantity deviates from an electrical physical quantity value within the predetermined normal range, When the ratio value between the first electrical physical quantity and the second electrical physical quantity is within the predetermined value range of the exceptional ratio as well as outside the predetermined normal value range, the connection is made on the power transmission path according to the backflow preventing line And reports the result of the wiring decision to the external management apparatus.
The method of claim 3,
Wherein,
In a relationship with the second electrical physical quantity measured by the second measuring section in a state in which the detour switch is turned off when the measured first electrical physical quantity deviates from an electrical physical quantity value within the predetermined normal range, By maintaining the turn-on state of the bypass switch when the ratio value between the first electrical physical quantity and the second electrical physical quantity does not fall within the pre-specified exception ratio value range beyond the predetermined normal value range, And the power input from the solar panel through the input terminal is output to the output terminal side through the backflow preventing line.
The method according to claim 1,
Wherein,
Generating an open / close control signal for turning on the bypass switch when the measured first electrical physical quantity corresponds to an electrical physical quantity value within the predefined normal range; Is output to the output terminal side via the bypass line.
6. The method of claim 5,
Wherein,
Wherein a ratio value between the first electrical physical quantity and the second electrical physical quantity is smaller than a predetermined normal value in a relationship with a second electrical physical quantity measured by the second measuring section when the bypass circuit is activated in response to the turn- And determines that the wiring has occurred on the power transmission path along the bypass line and reports the result of the wiring decision to the external management apparatus.

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