Solar power generation device

Abstract

Provided is a solar power generation device in which a light-emitting diode corresponding to a failed solar cell module can be emitted even in a solar cell panel constituted by connecting solar cell arrays in parallel and the failed solar cell module can be reliably and easily identified.　The solar power generation device comprises: a solar cell panel 2 in which solar cell arrays 1 are connected in parallel; a light-emitting diode 3 capable of emitting light in a state where a solar cell module T fails; a power conversion device 4 capable of outputting generated power; a voltage control means 7 for controlling the PV voltage; and a failure diagnosis instruction means 8 for instructing execution of failure diagnosis of the solar battery module T. When execution of the failure diagnosis is instructed by the failure diagnosis instruction means 8, the PV voltage of the solar battery panel 2 is controlled to be lowered by the voltage control means 7, and the light-emitting diode 3 connected in parallel with the failed solar battery module T is made to emit light.

Description

Solar power generation equipment

[0001] The present invention relates to a solar power generation device for generating electricity by receiving sunlight.

[0002] Solar cells convert light energy into electrical energy (power) by utilizing the photovoltaic effect, and because they can obtain power directly from sunlight, they have recently become popular as an environmentally friendly means of power generation. Such solar power generation devices using solar cells include a solar cell module, which is a combination of cells, the smallest unit of a solar cell, and a solar cell panel is made up of multiple arrays of modules connected in series or parallel.

[0003] To diagnose failures in such photovoltaic power generation equipment, a technology has been proposed in which light-emitting diodes are connected in parallel to each solar cell module in a solar cell array in which solar cell modules that receive sunlight and generate electricity are connected in series, so that the light-emitting diode corresponding to the failed solar cell module emits light (see Patent Document 1). This makes it easy to identify a failed solar cell panel among multiple solar cell modules and quickly replace it with a new solar cell module.

[0004] Japanese Patent Application Publication No. 9-148613

[0005] However, in the above-mentioned conventional technology, in the case of a solar panel configured by connecting solar cell arrays in parallel, a solar cell array having a faulty solar cell module has a low open circuit voltage and therefore no current flows, so that the light emitting diode corresponding to the faulty solar cell module cannot be made to emit light.

[0006] The present invention has been made in consideration of the above circumstances, and aims to provide a solar power generation device that can make a light-emitting diode corresponding to a faulty solar cell module emit light, even in a solar cell panel configured by connecting solar cell arrays in parallel, and can reliably and easily identify the faulty solar cell module.

[0007] The invention described in claim 1 is a solar power generation device comprising a solar cell array in which solar cell modules that receive sunlight and generate electricity are connected in series, a solar cell panel in which the solar cell array is connected in parallel, light-emitting diodes connected in parallel to the solar cell modules and capable of emitting light when the solar cell modules have failed, a power conversion device capable of outputting power generated by the solar cell panel, voltage control means for controlling the PV voltage of the solar cell panel, and fault diagnosis instruction means for instructing the execution of fault diagnosis of the solar cell modules, wherein when the execution of fault diagnosis is instructed by the fault diagnosis instruction means, the voltage control means controls the PV voltage of the solar cell panel to decrease, causing the light-emitting diodes connected in parallel to the failed solar cell module to emit light.

[0008] The invention of claim 2 is characterized in that, in the solar power generation device of claim 1, it is provided with a voltage setting means that sets the PV voltage to a predetermined value less than the open-circuit voltage of the solar cell module when the fault diagnosis instruction means instructs the execution of fault diagnosis, and the voltage control means controls the PV voltage to the predetermined value set by the voltage setting means, causing the light-emitting diode connected in parallel to the faulty solar cell module to emit light.

[0009] The invention of claim 3 is characterized in that, in the solar power generation device of claim 1, it is provided with a light-emitting circuit having a first circuit in which a resistor is connected in series to the light-emitting diode, a second circuit in which a resistor is connected in parallel to the first circuit, and a third circuit in which a diode is connected in series to the first circuit and the second circuit, and the light-emitting circuit is connected in parallel to the solar cell module.

[0010] The invention of claim 4 is characterized in that, in the solar power generation device of claim 1, it comprises a light-emitting circuit having a first circuit in which a constant current element is connected in series to the light-emitting diode, a second circuit in which a resistor is connected in parallel to the first circuit, and a third circuit in which diodes are connected in series to the first circuit and the second circuit, and the light-emitting circuit is connected in parallel to the solar cell module.

[0011] According to a fifth aspect of the present invention, in the solar power generation system of the first aspect, the solar cell array has holding means for holding the solar cell modules in an exchangeable manner.

[0012] The invention of claim 6 is characterized in that the solar power generation device of claim 1 is provided with a sunshade means that can be switched between an open state and a closed state at will, and the solar cell panel is attached to the sunshade means.

[0013] A seventh aspect of the present invention is a solar power generation system according to the sixth aspect, wherein the sunshade means is a blind, a curtain, or an awning.

[0014] According to an eighth aspect of the present invention, in the solar power generation system of the first aspect, the power conversion device performs maximum power point tracking control when outputting generated power from the solar cell panel.

[0015] According to the invention of claim 1, when the fault diagnosis instruction means instructs the execution of fault diagnosis, the voltage control means controls the PV voltage of the solar cell panel to decrease, causing the light-emitting diode connected in parallel to the faulty solar cell module to emit light. Therefore, even in a solar cell panel constructed by connecting solar cell arrays in parallel, the light-emitting diode corresponding to the faulty solar cell module can be made to emit light, and the faulty solar cell module can be identified reliably and easily.

[0016] According to the invention of claim 2, when the fault diagnosis instruction means instructs the execution of fault diagnosis, a voltage setting means is provided which sets the PV voltage to a predetermined value less than the open circuit voltage of the solar cell module, and the voltage control means controls the PV voltage to the predetermined value set by the voltage setting means and causes the light emitting diode connected in parallel to the faulty solar cell module to emit light.Therefore, even if, for example, there is one normal solar cell module and the remaining solar cell modules are faulty in the same solar cell array, the faulty solar cell module can be more reliably and easily identified.

[0017] According to the invention of claim 3, a light-emitting circuit is provided which has a first circuit in which a resistor is connected in series to a light-emitting diode, a second circuit in which a resistor is connected in parallel to the first circuit, and a third circuit in which a diode is connected in series to the first circuit and the second circuit, and the light-emitting circuit is connected in parallel to the solar cell module, so that the resistors and diodes of the first circuit and the second circuit can suppress the reverse voltage applied to the light-emitting diode during power generation, thereby preventing damage to the light-emitting diode.

[0018] According to the invention of claim 4, a light-emitting circuit is provided which has a first circuit in which a constant current element is connected in series to a light-emitting diode, a second circuit in which a resistor is connected in parallel to the first circuit, and a third circuit in which a diode is connected in series to the first circuit and the second circuit, and since the light-emitting circuit is connected in parallel to the solar cell module, the constant current element of the first circuit and the resistor and diode of the second circuit can suppress the reverse voltage applied to the light-emitting diode during power generation, preventing damage to the light-emitting diode.

[0019] According to the fifth aspect of the present invention, the solar cell array has holding means for holding the solar cell modules in a replaceable manner, so that each solar cell module can be easily replaced.

[0020] The invention described in claim 6 is provided with a sunshade means that can be switched between an open state and a closed state at will, and the solar panel is attached to the sunshade means, so that when the sunshade means is in the closed state, the solar panel outputs generated electricity, and when the sunshade means is in the open state, sunlight can be taken into the room.

[0021] In the invention of claim 7, the sunshade means is a blind, a curtain or an awning, so that a general-purpose sunshade means can be used, and the installation cost of the solar power generation device can be reduced.

[0022] According to the eighth aspect of the present invention, the power conversion device performs maximum power point tracking (MPPT) control when outputting generated power from the solar cell panel, so that the generated power can be output stably.

[0023] FIG. 1 is a block diagram showing a solar power generation device according to an embodiment of the present invention; FIG. 2 is a schematic diagram for explaining a solar cell array in the solar power generation device; FIG. 3 is a schematic diagram for explaining a solar cell module in the solar power generation device;

[0024] The present invention will be described in detail below with reference to the drawings. The solar power generation system according to the present invention receives sunlight and generates electricity, and includes a solar cell array 1, a solar cell panel 2, a power conversion device 4 having a power detection device 5, a voltage setting means 6, and a voltage control means 7, as shown in Figures 1 and 2.

[0025] 2 , the solar cell array 1 has a plurality of solar cell modules T connected in series to receive sunlight and generate electricity, and light-emitting diodes 3 connected in parallel to each solar cell module T and capable of emitting light even when the solar cell module T has a malfunction. The light-emitting diodes 3 are capable of emitting light even when the solar cell module T has a malfunction, and are connected in parallel to each solar cell module T in the solar cell array 1.

[0026] As shown in Fig. 3, a solar cell module T is made up of a plurality of solar cell cells C, which are the smallest units of a solar cell, sealed in a weatherproof package, and as shown in Fig. 2, a plurality of these solar cell modules T are connected in series to form a solar cell array 1. In addition, a diode g is connected to each solar cell array 1 to prevent backflow.

[0027] Furthermore, the solar cell array 1 in this embodiment has a holding means H that holds the solar cell modules T in a replaceable manner, as shown in Figures 6 and 7. The holding means H allows the solar cell modules T to be detached, and when the solar cell modules T are held, the solar cell modules T are connected in series and to the corresponding light-emitting diodes 3, as shown in Figure 2. In this way, the solar cell array 1 has the holding means H that holds the solar cell modules T in a replaceable manner, making it easy to replace each solar cell module T.

[0028] 1, the solar cell panel 2 is made up of solar cell arrays 1 connected in parallel, and each of the solar cell arrays 1 constituting the solar cell panel 2 is capable of receiving sunlight and generating power. The power conversion device 4 is connected to each solar cell array 1 and is capable of outputting the power generated by the solar cell panel 2 to an external load F (for example, a storage battery, a personal computer, a display, etc.).

[0029] Furthermore, the power conversion device 4 according to this embodiment is configured to perform maximum power point tracking control when outputting generated power (PV) from the solar cell panel 2. Maximum power point tracking control (MPPT) refers to control that automatically determines the optimal current x voltage value (maximum power point or optimal operating point) that can maximize output when the solar cell generates power, and can operate while tracking the optimal operating point, which constantly fluctuates due to changes in weather conditions, etc.

[0030] For example, in a type of maximum power point tracking control known as the climbing method, the voltage is changed in one direction (increase or decrease) on a PV curve that graphs voltage and power, and when the power changes from increasing to decreasing, the direction of the voltage change is reversed. By repeating this process, it is possible to control the power to the optimal operating point where it is always maximized. In this way, the power conversion device 4 according to this embodiment performs maximum power point tracking control when outputting generated power from the solar cell panel 2, thereby enabling stable output of generated power.

[0031] Furthermore, the power conversion device 4 according to this embodiment is connected to fault diagnosis instruction means 8 that instructs the execution of a fault diagnosis of the solar cell module T. In other words, by operating the fault diagnosis instruction means 8, it is possible to arbitrarily execute a fault diagnosis in the power conversion device 4. The fault diagnosis instruction means 8 is connected to the power conversion device 4 by wire or wirelessly, and the execution of a fault diagnosis can be instructed by a user through input operation.

[0032] Here, the power conversion device 4 according to this embodiment is configured to, when the fault diagnosis instruction means 8 instructs the execution of a fault diagnosis, control the voltage control means 7 to reduce the PV voltage of the solar cell panel 2, thereby causing the light-emitting diode 3 connected in parallel to the faulty solar cell module T to emit light, and as shown in Fig. 1, is configured to include a power detection device 5, a voltage setting means 6, and a voltage control means 7. The PV voltage refers to the voltage on the axis of a graph (PV curve) that represents the output characteristics when the solar cell panel 2 receives light and generates power.

[0033] The power detection device 5 detects the power generated by the solar cell panel 2, and control is performed by the voltage control means 7 based on the detected power generation. The voltage setting means 6 sets the PV voltage to a predetermined value less than the open-circuit voltage of the solar cell module T when the fault diagnosis instruction means 8 instructs the execution of fault diagnosis. The open-circuit voltage of the solar cell module T refers to the voltage at the output terminal of the solar cell module T when nothing is connected to the output terminal.

[0034] The voltage control means 7 controls the PV voltage of the solar cell panel 2, and controls the PV voltage to be a predetermined value set by the voltage setting means 6, thereby causing the light emitting diode 3 connected in parallel to the faulty solar cell module T to emit light. That is, as shown in Fig. 4, when generated power is output from the solar cell panel 2, the voltage control means 7 controls the PV voltage to be a maximum power point tracking (MPPT) control value, and when a fault diagnosis instruction is received from the fault diagnosis instruction means 8, controls the PV voltage to decrease to a predetermined value (in this embodiment, to less than the open circuit voltage of the solar cell module T).

[0035] Next, a control method (main flow) for a photovoltaic power generation system according to this embodiment will be described with reference to the flowchart in Fig. 5. First, in S1, it is determined whether or not a fault diagnosis instruction has been issued by the fault diagnosis instruction means 8. If no fault diagnosis instruction has been issued, in S2, a PV voltage that maximizes power generation is determined by maximum power point tracking (MPPT), and the process then proceeds to S3. If a fault diagnosis instruction has been issued, in S5, the voltage setting means 6 sets the PV voltage to a predetermined value (a predetermined value less than the open-circuit voltage of the solar cell module T), and the process then proceeds to S3. In S3, the voltage control means 7 controls the PV voltage to the PV voltage determined in S2 or the predetermined value set in S5, and in S4, the output voltage of the power conversion device 4 is controlled in accordance with the load F.

[0036] According to this embodiment, when the fault diagnosis instruction means 8 instructs the execution of a fault diagnosis, the voltage control means 7 controls the PV voltage of the solar cell panel 2 to decrease, causing the light-emitting diode 3 connected in parallel to the faulty solar cell module T to emit light. Therefore, even in a solar cell panel 2 constructed by connecting solar cell arrays 1 in parallel, the light-emitting diode 3 corresponding to the faulty solar cell module T can be made to emit light, and the faulty solar cell module T can be identified reliably and easily.

[0037] Furthermore, according to this embodiment, when the fault diagnosis instruction means 8 instructs the execution of a fault diagnosis, the voltage setting means 6 is provided which sets the PV voltage to a predetermined value which is less than the open circuit voltage of the solar cell module T, and the voltage control means 7 controls the PV voltage to the predetermined value set by the voltage setting means 6, causing the light emitting diode 3 connected in parallel to the faulty solar cell module T to emit light. Therefore, for example, even if there is one normal solar cell module T and the remaining solar cell modules T are faulty in the same solar cell array 1, the faulty solar cell module T can be more reliably and easily identified.

[0038] 2, the solar cell array 1 may be, for example, as shown in Fig. 8, equipped with a light-emitting circuit having a first circuit L1 in which a resistor r1 is connected in series to the light-emitting diodes 3, a second circuit L2 in which a resistor r2 is connected in parallel to the first circuit L1, and a third circuit L3 in which a diode g is connected in series to the first circuit L1 and the second circuit L2, and the light-emitting circuit is connected in parallel to the solar cell module T. With such a solar cell array 1, the resistors (r1, r2) of the first circuit L1 and the second circuit L2 and the diode g can suppress the reverse voltage applied to the light-emitting diodes 3 during power generation, thereby preventing damage to the light-emitting diodes 3.

[0039] 9, the solar cell array 1 may include a light-emitting circuit having a first circuit L1 in which a constant current element A is connected in series to the light-emitting diodes 3, a second circuit L2 in which a resistor r2 is connected in parallel to the first circuit L1, and a third circuit L3 in which a diode g is connected in series to the first circuit L1 and the second circuit L2, and the light-emitting circuit is connected in parallel to the solar cell module T. With this solar cell array 1, the constant current element A of the first circuit L1 and the resistor r2 and diode g of the second circuit L2 can suppress the reverse voltage applied to the light-emitting diodes 3 during power generation, thereby preventing damage to the light-emitting diodes 3.

[0040] The solar power generation device according to this embodiment may be provided with a sunshade means that can be switched between an open state and a closed state, and the solar cell panel 2 may be attached to the sunshade means. This allows the solar cell panel 2 to output generated power when the sunshade means is closed, and allows sunlight to enter the room when the sunshade means is open. The sunshade means may be a blind 9 as shown in Fig. 10, or an opening / closing means 10 made up of a curtain or awning as shown in Fig. 11.

[0041] For example, as shown in Fig. 10, when applied to a blind 9 having openable and closable slats 9a and a main body 9b, the solar cell array 1 can be attached to each of the multiple slats 9a extending in the left-right direction. Also, as shown in Fig. 11, when applied to a curtain or awning as an opening / closing means 10 having an openable and closable shading portion 10a and a main body 10b, the solar cell array 1 can be attached to the left and right of the shading portion 10a. This allows the use of a general-purpose sunshade means, thereby reducing the installation cost of the solar power generation device.

[0042] Although the present embodiment has been described above, the present invention is not limited to this, and may be, for example, a solar power generation device in which the solar cell panel 2 is attached to another openable / closable sunshade means, or further, a solar power generation device in which the solar cell panel 2 is attached to another part or location other than the sunshade means.

[0043] The present invention can also be applied to devices with different external shapes or devices with additional functions, provided that they have the same gist as the present invention.

[0044] REFERENCE SIGNS LIST 1 Solar cell array 2 Solar cell panel 3 Light-emitting diode 4 Power conversion device 5 Power detection device 6 Voltage setting means 7 Voltage control means 8 Fault diagnosis instruction means 9 Blind (sunshade means) 9a Slat 9b Main body 10 Curtain or awning (sunshade means) 10a Shading part 10b Main body T Solar cell module C Solar cell g Diode F Load H Holding means r1, r2 Resistor A Constant current element L1 First circuit L2 Second circuit L3 Third circuit

Claims

1. A photovoltaic power generation device comprising: a solar cell array in which solar cell modules that receive sunlight and generate electricity are connected in series; a solar cell panel in which the solar cell array is connected in parallel; light-emitting diodes connected in parallel to the solar cell modules and capable of emitting light when the solar cell modules have failed; a power conversion device capable of outputting power generated by the solar cell panel; voltage control means for controlling the PV voltage of the solar cell panel; and fault diagnosis instruction means for instructing the execution of a fault diagnosis of the solar cell module, wherein when an instruction to execute a fault diagnosis is given by the fault diagnosis instruction means, the voltage control means controls the PV voltage of the solar cell panel to decrease, thereby causing the light-emitting diodes connected in parallel to the failed solar cell module to emit light.

2. A solar power generation device as described in claim 1, further comprising a voltage setting means for setting the PV voltage to a predetermined value less than the open circuit voltage of the solar cell module when the fault diagnosis instruction means instructs the execution of the fault diagnosis, and the voltage control means controls the PV voltage to the predetermined value set by the voltage setting means, thereby causing the light-emitting diode connected in parallel to the failed solar cell module to emit light.

3. The solar power generation device according to claim 1, further comprising a light-emitting circuit having: a first circuit in which a resistor is connected in series to the light-emitting diode; a second circuit in which a resistor is connected in parallel to the first circuit; and a third circuit in which diodes are connected in series to the first circuit and the second circuit, and the light-emitting circuit is connected in parallel to the solar cell module.

4. The photovoltaic power generation device according to claim 1, further comprising a light-emitting circuit having: a first circuit in which a constant current element is connected in series to the light-emitting diode; a second circuit in which a resistor is connected in parallel to the first circuit; and a third circuit in which a diode is connected in series to the first circuit and the second circuit, and the light-emitting circuit is connected in parallel to the solar cell module.

5. The photovoltaic power generation device according to claim 1, wherein said solar cell array has a holding means for holding said solar cell module in a replaceable manner.

6. A photovoltaic power generation device according to claim 1, further comprising a sunshade means which can be switched between an open state and a closed state at will, said solar cell panel being attached to said sunshade means.

7. The solar power generating device according to claim 6, wherein the sunshade means is a blind, a curtain or an awning.

8. The photovoltaic power generation system according to claim 1, wherein said power conversion device performs maximum power point tracking control when outputting generated power from said solar cell panel.

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