WO2013042384A1

WO2013042384A1 - Solar power system, solar power system diagnostic device, and solar power system diagnostic method

Info

Publication number: WO2013042384A1
Application number: PCT/JP2012/051771
Authority: WO
Inventors: 利康樋熊; 紀之久代; 直之樋原; 忠昭坂本; 吉秋小泉
Original assignee: 三菱電機株式会社
Priority date: 2011-09-20
Filing date: 2012-01-27
Publication date: 2013-03-28
Also published as: JPWO2013042384A1; JP5744214B2

Abstract

A control unit (105) which a solar power system (100) comprises causes the consumption in a pulse shape of DC electricity which solar cell strings to be diagnosed (106A, B) output, and generates information to be diagnosed which denotes response characteristics of either current or voltage which are measured by a sensor unit (104) in the output from the solar cell strings to be diagnosed (106A, B). The control unit (105) computes a degree of deterioration of the solar cell strings to be diagnosed by comparing the information to be diagnosed with standard information. The standard information is information which denotes response characteristics of either current or voltage which it is possible to measure in the output from solar cell strings which have no faults when DC electricity which the solar cell strings which have no faults output is consumed in a pulse shape. When the degree of deterioration is greater than a threshold, the control unit (105) determines that a fault is present in the solar cell strings to be diagnosed.

Description

Photovoltaic power generation system, solar power generation system diagnostic device, and solar power generation system diagnostic method

The present invention relates to a solar power generation system, a solar power generation system diagnosis apparatus, and a solar power generation system diagnosis method.

Patent Document 1 discloses a solar cell array diagnostic apparatus that determines normality / abnormality of outputs of a plurality of solar cell arrays (also referred to as solar cell strings) constituting a solar cell panel of a photovoltaic power generation system. This solar cell array diagnostic apparatus includes a storage unit that stores in advance each standard output power value for a predetermined sunshine time for a plurality of solar cell arrays, and a standard output power value of an actual output power value of each array at the predetermined sunshine time. And a determination unit that compares the calculated ratio between the arrays to determine whether the output of the array is normal or abnormal.

JP 2005-340464 A

In the solar cell array diagnostic apparatus disclosed in Patent Document 1, measurement over a long period of time, for example, several days is required in order to accurately detect normality / abnormality of the solar cell array.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a solar power generation system and the like capable of diagnosing the presence or absence of a malfunction of a solar cell string in a short time.

The photovoltaic power generation system according to the first aspect of the present invention is:
A solar cell string to be diagnosed that receives sunlight and generates power and outputs DC power; and
A converter that converts the DC power output by the solar cell string to be diagnosed into AC power and supplies it to the power system;
Measuring means for measuring current or voltage at the output from the solar cell string to be diagnosed;
Consumption control means for controlling consumption of DC power output by the solar cell string to be diagnosed;
Generates diagnosis target information indicating response characteristics of current or voltage measured by the measurement unit when the DC power output from the diagnosis target solar cell string is consumed in a pulse shape by being controlled by the consumption control unit Generating means for
An acquisition means for acquiring standard information indicating a response characteristic of current or voltage that can be measured at an output from a solar cell string having no defect when the DC power output by the solar cell string having no defect is consumed in a pulse form;
A calculation means for calculating a degree of deterioration of the diagnostic target solar cell string by comparing the diagnosis target information and the standard information;
And determining means for determining that the solar cell string to be diagnosed is defective when the degree of deterioration is greater than a threshold value.

A diagnostic apparatus for a photovoltaic power generation system according to the second aspect of the present invention,
Measuring means for measuring the current or voltage at the output from the solar cell string to be diagnosed;
Consumption control means for controlling consumption of DC power output by the solar cell string to be diagnosed;
Generating means for generating diagnostic object information indicating response characteristics of current or voltage measured by the measuring means when DC power output from the diagnostic target solar cell string is consumed by the consumption control means When,
An acquisition means for acquiring standard information indicating a response characteristic of current or voltage that can be measured at an output from a solar cell string having no defect when the DC power output by the solar cell string having no defect is consumed in a pulse form;
A calculation means for calculating a degree of deterioration of the diagnostic target solar cell string by comparing the diagnosis target information and the standard information;
And determining means for determining that the solar cell string to be diagnosed is defective when the degree of deterioration is greater than a threshold value.

The solar power generation system diagnosis method according to the third aspect of the present invention provides:
DC power output from the solar cell string to be diagnosed is consumed in pulses,
When DC power output from the diagnostic target solar cell string is consumed in a pulsed manner, it generates diagnostic target information indicating current or voltage response characteristics measured at the output from the diagnostic target solar cell string. ,
Obtaining standard information indicating the response characteristics of current or voltage that can be measured at the output from the solar cell string without the defect when the DC power output by the solar cell string without the defect is consumed in the form of pulses,
By comparing the diagnosis object information and the standard information, the degree of deterioration of the diagnosis object solar cell string is calculated,
When the degree of deterioration is greater than a threshold value, it is determined that the solar cell string to be diagnosed has a problem.

According to this invention, based on the response characteristics of the current or voltage measured when the DC power output from the diagnostic target solar cell string is consumed in pulses, the presence or absence of a fault in the diagnostic target solar cell string is determined. to decide. The response characteristic can be obtained in a short time after the power is consumed. Therefore, it is possible to diagnose in a short time whether or not the solar cell string is defective.

It is a figure which shows the structure of the solar energy power generation system which concerns on Embodiment 1. FIG. FIG. 3 is a diagram illustrating a configuration of a control unit according to the first embodiment. It is a figure which shows the impulse response at the time of consuming the DC power from the solar cell string used as a diagnostic object in the pulse form. It is a figure which shows an example of the content of standard information. It is a figure which shows the impulse response at the time of consuming the direct-current power from the solar cell string without a malfunction in a pulse form. It is a flowchart of the separate diagnostic process which the solar energy power generation system which concerns on Embodiment 1 performs. It is a flowchart of the whole diagnosis process which the solar energy power generation system which concerns on Embodiment 1 performs. It is a figure which shows the structure of the solar energy power generation system which concerns on Embodiment 2. FIG. It is a figure which shows the structure of the control part which concerns on Embodiment 2. FIG. It is a flowchart of the separate diagnostic process which the solar energy power generation system which concerns on Embodiment 2 performs. It is a flowchart of the whole diagnosis process which the solar energy power generation system which concerns on Embodiment 2 performs.

Embodiments of the present invention will be described with reference to the drawings.

Embodiment 1. FIG.
The photovoltaic power generation system 100 according to the first embodiment of the present invention is a system having a function of diagnosing the presence or absence of defects in the solar cell panel 101. As shown in FIG. 1, the solar cell panel 101 and the DC / AC A conversion device 102, a circuit opening / closing unit 103, a sensor unit 104, and a control unit 105 are provided.

The solar cell panel 101 includes two

solar cell strings

106A and 106B. Each of the

solar battery strings

106A and 106B is formed by connecting solar battery modules, which are aggregates of solar battery cells that receive sunlight to generate power, in series. Each of the

solar cell strings

106A and 106B outputs the generated DC power.

The DC / AC conversion device 102 is an example of a conversion unit that converts DC power output from the solar cell panel 101 into AC power and supplies the converted AC power to the power system. Further, the DC / AC conversion apparatus 102 according to the present embodiment converts DC power into AC power and supplies it to the power system according to control by the control unit 105. As a result, the DC / AC converter 102 causes the load unit (not shown) connected to the power system to consume the DC power output from the

solar cell strings

106A and 106B according to the control by the control unit 105. it can.

Furthermore, as shown in FIG. 1, the DC / AC conversion apparatus 102 includes a notification unit 107 for notifying the user of a problem that the solar battery panel 101 has a problem. The notification unit 107 includes, for example, a display panel that presents character information to the user, a speaker, a lamp, and the like. Note that the notification unit 107 may be provided in another element such as the circuit opening / closing unit 103 and the control unit 105 instead of the DC / AC conversion device 102. The power generation system 100 may be provided.

The circuit open / close unit 103 includes

electromagnetic switches

108A and 108B that switch electrical connection states (energization and disconnection) in response to a control signal from the control unit 105. The electromagnetic switch 108A switches the electrical connection state between the solar cell string 106A and the DC / AC converter 102 to either energization or disconnection. The electromagnetic switch 108B switches the electrical connection state between the solar cell string 106B and the DC / AC converter 102 to either energization or disconnection.

Each of the

electromagnetic switches

108A and 108B can switch the connection state independently. When one of the

electromagnetic switches

108A and 108B is set to energized and the other connected state is set to disconnected, the solar cell string corresponding thereto via one of the

electromagnetic switches

108A and 108B set to energized DC power output from one of 106A and 106B is supplied to the DC / AC converter 102. Further, when the connection state of both of the

electromagnetic switches

108A and 108B is set to energized, the DC power output from both the

solar cell strings

106A and 106B is aggregated (added) to the DC / AC converter 102. Supplied.

The sensor unit 104 is provided between the DC / AC converter 102 and the circuit opening / closing unit 103, and includes a sensor for measuring a current or a voltage in a wiring that electrically connects them. The sensor unit 104 outputs a signal (measurement information) indicating the measured current value or voltage value. The sensor unit 104 is an example of a measuring unit that measures current or voltage in the output from the

solar cell strings

106A and 106B.

Note that the sensor unit 104 may be built in the DC / AC conversion device 102, the circuit opening / closing unit 103, or the like, and may be detachably provided on these. In addition, the sensor unit 104 may be provided in a wiring that electrically connects the DC / AC converter 102, the circuit opening / closing unit 103, and the

solar cell strings

106A and 106B.

The control unit 105 controls the switching of each of the

electromagnetic switches

108A and 108B included in the circuit switching unit 103 and the amount of power supplied from the DC / AC converter 102 to the power system. By controlling the opening / closing of each of the

electromagnetic switches

108A and 108B and the amount of power supplied from the DC / AC converter 102, the control unit 105 can output the direct current output from each or all of the

solar cell strings

106A and 106B. Electric power can be consumed in pulses. The control unit 105 controls the DC / AC converter 102 so that a predetermined amount of power is consumed.

When a predetermined amount of DC power is consumed in a pulsed manner, the control unit 105 acquires measurement information, and based on the acquired measurement information, determines whether or not each of the

solar cell strings

106A and 106B has a defect. to decide.

When it is determined that there is a defect, the control unit 105 further controls, for example, the DC / AC converter 102 or the circuit opening / closing unit 103 so as to suppress the amount of current flowing through the defective

solar cell strings

106A and 106B. In this case, the control unit 105 further controls the notification unit 107 to notify the user that there is a problem.

FIG. 2 shows details of the configuration of the control unit 105. As shown in the figure, the control unit 105 includes an opening / closing control unit 111, a consumption control unit 112, a measurement information acquisition unit 113, a generation unit 114, a storage unit 115, a standard information acquisition unit 116, and a calculation unit. 117, a determination unit 118, a supply power control unit 119, and a notification control unit 120.

The opening / closing control unit 111 controls the connection state of each of the

electromagnetic switches

108A and 108B included in the circuit switching unit 103.

The consumption control unit 112 controls the DC / AC conversion device 102 so that the DC power output from the

solar cell strings

106A and 106B and supplied to the DC / AC conversion device 102 via the circuit opening / closing unit 103 is supplied to the power system. Output. The consumption control unit 112 controls the DC / AC conversion device 102 so that the power output from the DC / AC conversion device 102 to the power system becomes a predetermined amount in the form of a pulse. A given amount of power can be consumed. The circuit open / close unit 103 can switch the connection state for each of the

solar cell strings

106A and 106B under the control of the open / close control unit 111 as described above. Therefore, the consumption control unit 112 can selectively consume the DC power output from one of the

solar cell strings

106A and 106B by operating in conjunction with the open / close control unit 111, and both. It is also possible to consume the DC power output from the. Thereby, the

solar cell strings

106A and 106B to be diagnosed can be switched to either one or the whole.

The measurement information acquisition unit 113 acquires measurement information from the sensor unit 104.

The generation unit 114 generates diagnosis target information indicating the response characteristics RF1 of the

solar cell strings

106A and 106B to be diagnosed. The response characteristic RF1 is a value indicating a characteristic of a current (voltage) measured by the sensor unit 104 when a predetermined amount of power is consumed in a pulse shape among the DC power output from the

solar cell strings

106A and 106B. More specifically, the DC power is output from the

solar cell strings

106A and 106B to be diagnosed by the consumption control unit 112 controlling the DC / AC converter 102.

In the present embodiment, the rate of change of the current value measured by the sensor unit 104 when a predetermined amount of DC power is consumed in a pulse shape is adopted as the response characteristic RF1 of the

solar cell strings

106A and 106B to be diagnosed. The More specifically, for example, the response characteristic RF1 is a value obtained from 0.7Id / t1 using the change in current value shown in FIG. In FIG. 3, the horizontal axis represents the elapsed time (seconds), and the vertical axis represents the current value (A) measured by the sensor unit 104.

The stable current value Id indicates that the output from the

solar cell strings

106A and 106B is stable after a predetermined amount of DC power is consumed in a pulsed manner when there is no problem in the

solar cell strings

106A and 106B to be diagnosed. It is a current value that is sometimes measured. This direct-current power is output from the

solar cell strings

106A and 106B that are free from defects, as controlled by the consumption control unit 112. Here, the solar cell string having no defect means a solar cell string of the same type as the

solar cell strings

106A and 106B and having no defect or deterioration.

The response time t1 is the time required from the time T0 until the current value measured by the sensor unit 104 reaches 0.7 times (0.7Id) of Id. At time T0, when the consumption control unit 112 controls the DC / AC converter 102, a predetermined amount of electric power is consumed in pulses in the DC power output from the

solar cell strings

106A and 106B to be diagnosed. It is time.

Note that the response characteristic RF1 described with reference to FIG. 3 is merely an example. For example, the constant multiplied by the stable current value Id is not limited to 0.7, and may be any predetermined value. Further, the response time t1 itself may be adopted as the response characteristic RF1. Further, in order to determine the response characteristic RF1, a voltage value may be employed instead of the current value.

Reference is now made again to FIG.
The storage unit 115 stores standard information 121. The standard information 121 is information indicating the response characteristic RF0 of the solar cell string having no defect. The response characteristic RF0 of the solar cell string having no fault is obtained when the DC power output from the solar cell string having no fault is consumed under the same condition as that by the consumption control unit 112, from the solar cell string having no fault. It is the response characteristic for the current (voltage) that can be measured at the output.

The standard information according to the present embodiment is information indicating a value obtained from 0.7Id / t0 as shown in FIG. Here, 0.7Id represents 0.7 times the stable current value Id in the solar cell string having no defect, as in the case of the

solar cell strings

106A and 106B to be diagnosed. This coefficient 0.7 may be the same value as the coefficient multiplied by the stable current value Id in the response characteristics RF1 of the

solar cell strings

106A and 106B to be diagnosed. As shown in FIG. 5, the response time t0 is the time required for the current value to reach 0.7Id after consuming DC power under the same conditions as in the case of the consumption control unit 112 in the solar cell string having no defect. It is.

In addition, when the response time t1 itself is adopted as the response characteristic RF1 of the

solar cell strings

106A and 106B to be diagnosed, the response time t0 itself is included in the response characteristic RF0 of the stable current value Id in the solar cell string having no defect. It should be adopted. In addition, when a voltage value is used to determine the response characteristics RF1 of the

solar cell strings

106A and 106B, the voltage value may be used to determine the response characteristics RF0 of the solar cell string having no defects. .

Such standard information 121 may be information indicating response characteristics obtained based on, for example, design and testing of the

solar cell strings

106A and 106B. Information indicating response characteristics based on design, testing, and the like may be associated with information (type information) indicating the type such as the model number of the

solar cell strings

106A and 106B in the standard information 121.

Further, for example, the standard information 121 may be information indicating response characteristics based on a measurement result when the actually installed

solar cell strings

106A and 106B are operated for the first time. The response characteristic based on the actual measurement result may be associated with information (individual identification information) for distinguishing each and all of the installed

solar cell strings

106A and 106B in the standard information 121.

From here, it demonstrates with reference to FIG.
The standard information acquisition unit 116 acquires standard information 121 corresponding to the

solar cell strings

106A and 106B to be diagnosed from the storage unit 115.

In the standard information 121, when information indicating response characteristics is associated with type information, the standard information acquisition unit 116 may acquire information indicating response characteristics associated with the type specified by the user. Similarly, in the standard information 121, when the information indicating the response characteristic is associated with the individual specific information, the standard information acquisition unit 116 is associated with each or all of the

solar cell strings

106A and 106B designated by the user. It is preferable to acquire information indicating the response characteristics. The designation of the user is performed by operating an input unit (not shown) such as an operation button, for example. Furthermore, when the type of the

solar cell strings

106A and 106B and each and all of the installed

solar cell strings

106A and 106B can be automatically identified, the standard information acquisition unit 116 determines the solar cell string 106A to be diagnosed. , 106B, type information or individual specific information may be determined. And the standard information acquisition part 116 may acquire the information which shows the response characteristic linked | related with the classification information according to a discrimination | determination result, or individual specific information.

The calculation unit 117 compares the diagnosis target information generated by the generation unit 114 and the standard information 121 acquired by the standard information acquisition unit 116 with the value obtained by comparing the solar cell string 106A, It is calculated as the deterioration level of 106B.

The degree of deterioration is an index indicating the degree of deterioration or failure occurring in the

solar cell strings

106A and 106B that are to be diagnosed, with the solar cell string having no failure as a reference. The degree of deterioration is, for example, the difference between the response characteristic indicated by the diagnosis target information and the response characteristic indicated by the standard information 121. The degree of deterioration may be a ratio of response characteristics indicated by the diagnosis target information and the standard information 121.

Generally, when the

solar cell strings

106A and 106B are used for a long period of time, an aging deterioration or a malfunction that an electric resistance increases is caused. As this progresses, it becomes impossible to obtain outputs from the

solar cell strings

106A and 106B. Therefore, the degree of deterioration of the

solar cell strings

106A and 106B can be measured by the degree of deterioration based on the comparison of the response characteristics as described above.

The determination unit 118 compares the degree of deterioration calculated by the calculation unit 117 with a threshold value, and as a result of comparison, if the degree of deterioration is greater than the threshold value, each or all of the

solar cell strings

106A and 106B that are to be diagnosed It is determined that there is a problem. As a result of the comparison, when the degree of deterioration is equal to or less than the threshold value, the determination unit 118 determines that each or all of the solar cell strings 106 </ b> A and 106 </ b> B to be diagnosed are not defective. Note that the information indicating the threshold is stored in the storage unit 115, and the determination unit 118 may refer to the information. Information indicating the threshold value may be held in the determination unit 118.

The supply power control unit 119 is an example of a protection unit that suppresses the current output from the

solar cell strings

106A and 106B that are determined to be defective when the determination unit 118 determines that there is a problem. Controls the AC converter 102 or the circuit switching unit 103.

Specifically, for example, the power supply control unit 119 controls the circuit switching unit 103 so as to intermittently switch the connection state of the

electromagnetic switches

108A and 108B. In this case, the supplied power control unit 119 may intermittently switch the connection state of only the

electromagnetic switches

108A and 108B connected to the

solar cell strings

106A and 106B that are determined to be defective. The connection states of both of the

devices

108A and 108B may be switched intermittently.

Further, for example, the supply power control unit 119 may control the amount of power supplied by the DC / AC conversion device 102 so as to suppress the current output from the

solar cell strings

106A and 106B that are determined to be defective. .

Note that the solar power generation system 100 includes a plurality of DC / AC converters individually connected to the

solar cell strings

106A and 106B, and the supply power control unit 119 is supplied by each of the DC / AC converters. The amount of power to be controlled may be controlled.

The notification control unit 120 transmits a control signal to the notification unit 107, thereby causing the notification unit 107 to notify the determination result to the user. For example, when the determination unit 118 determines that there is a problem, the notification control unit 120 provides information indicating that the

solar cell strings

106A and 106B have a problem, or the solar cell string 106A, A control signal including information for specifying 106B is transmitted to notification section 107. Further, for example, when the determination unit 118 determines that there is no defect, the notification control unit 120 specifies information indicating that there is no defect, or the

solar cell strings

106A and 106B that are determined to have no defect. A control signal including information is transmitted to the notification unit 107.

Such a control unit 105 is realized by, for example, combining one or a plurality of processors that execute a computer program, a RAM (Random Access Memory), a flash memory, an input / output I / F (interface) with the outside, and the like. .

So far, the configuration of the solar power generation system 100 according to Embodiment 1 has been described. From here, the process which the solar power generation system 100 performs in order to diagnose the state of the solar cell panel 101 (

solar cell string

106A, 106B) is demonstrated with reference to figures.

FIG. 6 shows a process (individual diagnosis process) executed by the solar power generation system 100 to individually diagnose each of the

solar cell strings

106A and 106B. In the individual diagnosis processing of the present embodiment, an example in which diagnosis is performed in the order of the solar cell string 106A and the solar cell string 106B will be described. An example in which the

solar cell strings

106A and 106B are diagnosed based on the current value in the output from the

solar cell strings

106A and 106B will be described.

Note that the order of the solar cell strings to be diagnosed in the individual diagnostic process may be changed as appropriate. Moreover, the diagnosis of only one

solar cell string

106A, 106B designated by the user may be executed.

The control unit 105 executes the following processing (steps S102 to S113) for each of the

solar cell strings

106A and 106B (step S101; loop A).

The switching control unit 111 sets the connection state of the electromagnetic switch 108A connected to the solar cell string 106A to energization, and sets the connection state of the electromagnetic switch 108B connected to the solar cell string 106B to disconnection ( Step S102).

The consumption control unit 112 controls the DC / AC converter 102, thereby consuming a predetermined amount of power in a pulsed manner (step S103). Here, in the connection state setting process (step S102), since the electromagnetic switch 108A is set to be energized and the electromagnetic switch 108B is set to be disconnected, the DC power output from the solar cell string 106A is consumed. .

The sensor unit 104 measures the current value (response current) in the output from the solar cell string 106A and outputs measurement information (step S104). The measurement information acquisition unit 113 acquires measurement information output from the sensor unit 104 (step S105).

The generation unit 114 calculates the response characteristic RF1 of the solar cell string 106A by referring to the measurement information acquired by the measurement information acquisition unit 113, and generates diagnosis target information (step S106).

The standard information acquisition unit 116 acquires the standard information 121 corresponding to the solar cell string 106A from the storage unit 115 (step S107).

The calculation unit 117 calculates a difference RF0−RF1 between the response characteristic RF1 indicated by the diagnosis target information generated by the generation unit 114 and the response characteristic RF0 indicated by the standard information 121 as the deterioration level, and generates information indicating the calculated deterioration level. (Step S108).

The determining unit 118 compares the degree of deterioration calculated by the calculating unit 117 with a predetermined threshold value (step S109). When the degree of deterioration is larger than the threshold (step S109; Yes), the determination unit 118 determines that there is a problem with the solar cell string 106A (step S110).

If it is determined that there is a problem (step S110), the supply power control unit 119 controls the AC / DC converter 102 so as to suppress power consumption in the output from the solar cell string 106A (step S111). And the notification control part 120 transmits the control signal for controlling to notify the information which shows that the solar cell string 106A has a malfunction to the notification part 107 (step S112).

When the deterioration level is equal to or less than the threshold (step S109; No), the determination unit 118 determines that there is no problem with the solar cell string 106A (step S113). Thus, the individual diagnosis process for the solar cell string 106A is completed.

Next, the control unit 105 executes a series of processes (steps S102 to S113) included in the loop A for the solar cell string 106B. A series of processing (steps S102 to S113) executed on the solar cell string 106B is the same as that described above with respect to the solar cell string 106A replaced with the solar cell string 106B. Therefore, a detailed description of a series of processing (steps S102 to S113) regarding the solar cell string 106B is omitted. Thereby, the control part 105 complete | finishes an individual diagnostic process.

As described above, in the individual diagnosis processing, the consumption control unit 112 performs DC / DC conversion when the open / close control unit 111 connects any one of the

solar cell strings

106A and 106B to be diagnosed to the DC / AC converter 102. The AC converter 102 is controlled. As a result, the DC power output from the solar cell string 106A or B connected to the DC / AC converter 102 is consumed in a pulsed manner, so whether each of the

solar cell strings

106A and 106B has a defect is individually determined. Can be diagnosed. As a result, detailed diagnosis of the

solar cell strings

106A and 106B becomes possible.

From here, with reference to FIG. 7, the process (overall diagnosis process) which the solar power generation system 100 performs in order to diagnose both the

solar cell string

106A, 106B simultaneously is demonstrated.

The opening / closing control unit 111 sets the connection state of both the

electromagnetic switches

108A and 108B to energization (step S201). Thereafter, a series of processes from the power consumption process (step S103) to the determination process for no defect (step S113) is executed.

Each of these series of processes (steps S103 to S113) is obtained by replacing either one of the

solar cell strings

106A and 106B with both of the processes assigned the same reference numerals in the individual diagnosis process (see FIG. 6). It is the same. Therefore, detailed description regarding each of the series of processes (steps S103 to S113) is omitted.

As described above, in the overall diagnosis process, the consumption control unit 112 performs DC / DC conversion when the open / close control unit 111 connects both (all) the

solar cell strings

106A and 106B to be diagnosed to the DC / AC converter 102. The AC converter 102 is controlled. As a result, the DC power output from both of the

solar cell strings

106A and 106B can be consumed in a pulsed manner, and it is diagnosed in a short time whether there is a problem somewhere in the

solar cell strings

106A and 106B. It becomes possible to do.

So far, Embodiment 1 of the present invention has been described. According to the first embodiment, the DC / AC converter 102 is controlled to consume a predetermined amount of electric power in a pulsed manner, so that the malfunction of the

solar cell strings

106A and 106B can be diagnosed. When a predetermined amount of power is consumed in a pulsed manner, the current or voltage at the output from the

solar cell strings

106A and 106B is normally stabilized in a few seconds. Therefore, according to the present embodiment, it is possible to make a diagnosis in a few seconds to a few tens of seconds, and it is possible to diagnose in a short time whether or not the

solar cell strings

106A and 106B are defective.

Further, according to the present embodiment, the user can diagnose the malfunction of the

solar cell strings

106A and 106B only by operating the control unit 105. Therefore, for example, it is not necessary to work on the roof of the house where the solar cell panel 101 is installed, and it becomes possible to improve the safety of the work. In addition, for example, it is not necessary for the user to set other devices or devices such as the DC / AC conversion device 102 and the circuit opening / closing unit 103, and the work efficiency can be improved.

Furthermore, according to this embodiment, it is possible to switch the diagnosis target to each of the

solar cell strings

106A and 106B and the whole. For example, when the number of

solar cell strings

106A and 106B is large, the entire

solar cell strings

106A and 106B may be diagnosed first. And it is good also as not diagnosing separately when it diagnoses that there exists a malfunction, and when it diagnoses that there is no malfunction. As described above, since the diagnosis target can be switched, it is possible to efficiently diagnose whether or not the

solar cell strings

106A and 106B are defective.

Furthermore, a general photovoltaic power generation system includes a solar cell panel, an AC / DC converter, a circuit opening / closing unit, a sensor unit, and a control unit for controlling them. The photovoltaic power generation system 100 according to the present embodiment adds the function of the control unit 105 described in the present embodiment to the control unit of a general photovoltaic power generation system, and includes an AC / DC conversion device 102 and a circuit opening / closing unit 103. This is realized by enabling the control unit 105 to be remotely controlled. That is, the solar power generation system 100 according to the present embodiment may have the same hardware configuration as a general solar power generation system. As a result, the solar power generation system 100 capable of diagnosing the

solar cell strings

106A and 106B can be realized with a simple configuration and at a low price.

Furthermore, according to the present embodiment, when it is determined that the

solar cell strings

106A and 106B are defective, power supply from the defective

solar cell strings

106A and 106B is suppressed. As a result, it is possible to reduce the load on the defective

solar cell strings

106A and 106B and suppress the progress of the defect.

Embodiment 2. FIG.
In the second embodiment, a solar power generation system 200 that is particularly useful when diagnosing the presence or absence of defects in the

solar cell strings

106A and 106B in the solar power generation system 200 including a switch that requires manual operation will be described. In the present embodiment, the same elements as those described in the first embodiment are denoted by the same reference numerals.

As shown in FIG. 8, the solar power generation system 200 includes a solar cell panel 101 including

solar cell strings

106A and 106B similar to those of the first embodiment. The solar power generation system 200 includes a DC / AC conversion device 202, a connection box 231, a load unit 232, and a control unit 205.

Similarly to the DC / AC converter 102 according to the first embodiment, the DC / AC converter 202 converts the DC power output from the solar cell panel 101 into AC power, and supplies the converted AC power to the power system. A function as a conversion unit is provided. Further, the DC / AC conversion device 202 includes a notification unit 107 as in the case of the DC / AC conversion device 102 according to the first embodiment. Unlike the DC / AC conversion apparatus 102 according to the first embodiment, the DC / AC conversion apparatus 202 according to the present embodiment consumes DC power output from the

solar cell strings

106A and 106B according to the control of the consumption control unit 112. It does not have to have a function.

The connection box 231 includes

switches

233A and 233B for switching the connection state between the

solar cell strings

106A and 106B and the DC / AC converter 202 when the user manually operates. When using the electric power generated by the solar power generation system 200, the connection state of the

switches

233A and 233B is normally set to energization. When diagnosing the presence or absence of defects in the

solar cell strings

106A and 106B, the connection states of the

switches

233A and 233B are both set to disconnected.

The load unit 232 includes

electronic loaders

234A and 234B and a sensor unit 204.

The electronic loader 234A (234B) includes, for example, a resistor and a relay switch (not shown) that are electrically connected to wiring that electrically connects the solar cell string 106A (106B) and the switch 233A (234B). ). The electronic loader 234A can consume the DC power output from the solar cell string 106A in a pulsed manner. Further, the electronic loader 234B can consume the DC power output from the solar cell string 106B in a pulse shape. Each of the

electronic loads

234A and 234B can consume a predetermined amount of power. Such

electronic loaders

234A and 234B are an example of a consumption means capable of independently pulsing the DC power output from each of the

solar cell strings

106A and 106B to be diagnosed.

The sensor unit 204 is an example of a measurement unit, and when DC power output from one or both of the

solar cell strings

106A and 106B is consumed by one or both of the

electronic loaders

234A and 234B, It includes a current or a sensor that measures the current. The sensor unit 204 outputs a signal (measurement information) indicating the measured current value or voltage value. The sensor unit 204 may not be provided in the load unit 232, and can measure a current substantially equal to a current or voltage of a wiring that electrically connects the solar cell panel 101 and the

switches

233A and 233B. It may be provided in any place.

As shown in FIG. 9, the control unit 205 includes a generation unit 114, a storage unit 115, a standard information acquisition unit 116, a calculation unit 117, a determination unit 118, and a supply power control unit, as in the first embodiment. 119 and a notification control unit 120. Further, the control unit 205 includes a consumption control unit 212 and a measurement information acquisition unit 213.

The consumption control unit 212 controls the

electronic loaders

234A and 234B to consume a predetermined amount of electric power in the form of pulses among the DC power output from the

solar cell strings

106A and 106B.

The measurement information acquisition unit 213 acquires measurement information from the sensor unit 204.

From here, the process (individual diagnostic process) which the photovoltaic power generation system 200 which concerns on Embodiment 2 performs in order to diagnose the state of the solar cell panel 101 (

solar cell string

106A, 106B) is demonstrated with reference to FIG. To do. The individual diagnosis process according to the present embodiment is started after the connection state of both

switches

233A and 233B is manually set to disconnection.

The control unit 205 executes the following processing (steps S302 to S304, S106 to S113) for each of the

solar cell strings

106A and 106B (step S301; loop B).

The consumption control unit 212 controls the electronic loader 234A, and thereby consumes a predetermined amount of electric power in the form of pulses among the DC power output from the solar cell string 106A (step S302).

The sensor unit 204 measures the current value (response current) in the output from the solar cell string 106A and outputs measurement information (step S303). The measurement information acquisition unit 213 acquires measurement information output from the sensor unit 104 (step S304).

Subsequently, as in the first embodiment, the control unit 205 executes processes from the diagnosis target information generation process (step S106) to the determination process without defect (step S113). Thus, the individual diagnosis process for the solar cell string 106A is completed.

Next, the control unit 205 executes a series of processes (steps S302 to S304, S106 to S113) included in the loop B for the solar cell string 106B. A series of processing (steps S302 to S304, S106 to S113) executed on the solar cell string 106B is the same as that described above with respect to the solar cell string 106A replaced with the solar cell string 106B. Therefore, a detailed description of a series of processing (steps S302 to S304, S106 to S113) related to the solar cell string 106B is omitted. As a result, the control unit 205 ends the individual diagnosis process.

According to such an individual diagnosis process, as in the case of the individual diagnosis process according to the first embodiment, it is possible to make a detailed diagnosis as to whether or not each of the

solar cell strings

106A and 106B has a defect.

Note that the

electronic loads

234A and 234B may be configured so that the DC power output from each of the

solar cell strings

106A and 106B can be consumed simultaneously. According to this, the power consumption process (step S302) to the measurement information acquisition process (step S304) shown in FIG. 10 can be collectively executed for all the

solar cell strings

106A and 106B. Therefore, the control unit 205 can simultaneously acquire measurement information for each of the

solar cell strings

106A and 106B.

Therefore, as described with reference to FIG. 10, each diagnosis (steps S302 to S304, S106 to S113) is performed individually for the

solar cell strings

106A and 106B earlier than the sequential diagnosis for each of the

solar cell strings

106A and 106B. Can be executed. Such a configuration is particularly useful when, for example, the solar cell panel 101 includes a large number of solar cell strings.

From here, with reference to FIG. 11, the process (overall diagnosis process) which the solar power generation system 200 performs in order to diagnose both the

solar cell string

106A, 106B is demonstrated. The overall diagnosis process according to this embodiment is started after the connection state of both

switches

233A and 233B is manually set to disconnection.

The consumption control unit 212 controls the

electronic loaders

234A and 234B, and thereby consumes a predetermined amount of electric power in a pulse shape from the DC power output from both (whole) of the

solar cell strings

106A and 106B (step). S401). The sensor unit 204 measures current values in outputs from both the

solar cell strings

106A and 106B and outputs measurement information (step S402). Thereafter, the processes from the measurement information acquisition process (step S304) and the diagnosis target information generation process (step S106) to the determination process for no defect (step S113) are executed.

Each of the series of processes (steps S304, S106 to S113) is performed by replacing either one of the

solar cell strings

106A and 106B with both of the processes with the same reference numerals in the individual diagnosis process (see FIG. 10). It is the same as that. Therefore, detailed description regarding each of the series of processing (steps S304, S106 to S113) is omitted.

According to such a whole diagnosis process, as in the case of the whole diagnosis process according to the first embodiment, it is possible to diagnose in a short time whether there is a defect somewhere in the entire

solar cell strings

106A and 106B. It becomes possible.

So far, the second embodiment of the present invention has been described. According to the second embodiment, as in the first embodiment, it is possible to diagnose in a short time whether or not the

solar cell strings

106A and 106B are defective. Further, as in the first embodiment, it is possible to improve the safety and efficiency of work. Furthermore, as in the first embodiment, the diagnosis target can be switched, so that it is possible to efficiently diagnose the presence or absence of defects in the

solar cell strings

106A and 106B.

Furthermore, according to the present embodiment, it is possible to easily diagnose the presence or absence of a defect in the already installed solar cell panel 101 (

solar cell strings

106A and 106B). A general photovoltaic power generation system includes a solar cell panel 101, a connection box 231, and a DC / AC converter 102. Realizing the configuration of the photovoltaic power generation system 200 according to the present embodiment by simply connecting the wiring of the load unit 232 between the solar cell panel 101 and the junction box 231 and installing the control unit 205. Because you can.

Further, according to the present embodiment, as in the first embodiment, since the power supply from the defective

solar cell strings

106A and 106B is suppressed, the load on the defective

solar cell strings

106A and 106B is reduced, It becomes possible to suppress the progress of the defect.

In addition, this invention also includes the diagnostic apparatus of a solar power generation system provided with the load part 232 and the control part 205 which were demonstrated by this embodiment. As described above, the load unit 232 of the solar power generation system diagnostic device can be easily attached to a general solar power generation system that has already been installed. According to the diagnostic device of the photovoltaic power generation system, for example, it is possible to easily diagnose the presence or absence of a defect in the already installed solar cell panel 101 (

solar cell strings

106A and 106B). And in the diagnosis of the solar cell panel 101 (

solar cell strings

106A and 106B) using the diagnostic device of the solar power generation system, the same effect as the solar power generation system 200 according to the second embodiment is obtained.

As mentioned above, although embodiment of this invention was described including the modification, this invention is not limited to embodiment and its modification, For example, the aspect which combined each embodiment, and they are equivalent The technical scope is also included.

This application is based on Japanese Patent Application No. 2011-205103 filed on Sep. 20, 2011. The specification, claims, and entire drawings are incorporated in this specification.

The present invention is suitably employed in a solar power generation system capable of diagnosing whether or not a solar cell string is defective, a solar power generation system diagnosis device or a diagnosis method for performing the diagnosis, and the like.

DESCRIPTION OF SYMBOLS 100,200 Solar power generation system 101 Solar cell panel 102,202 DC / AC converter 103 Circuit switching part 104,204 Sensor part 105,205

Control part

106A, 106B Solar cell string 107

Notification part

108A, 108B Electromagnetic switch 111 Opening / closing Control unit 112,212 Consumption control unit 113,213 Measurement information acquisition unit 114 Generation unit 115 Storage unit 116 Standard information acquisition unit 117 Calculation unit 118 Judgment unit 119 Supply power control unit 120 Notification control unit 121 Standard information 231 Connection box 232

Load unit

233A,

233B Switch

234A, 234B Electronic load

Claims

A solar cell string to be diagnosed that receives sunlight and generates power and outputs DC power; and
A converter that converts the DC power output by the solar cell string to be diagnosed into AC power and supplies it to the power system;
Measuring means for measuring current or voltage at the output from the solar cell string to be diagnosed;
Consumption control means for controlling consumption of DC power output by the solar cell string to be diagnosed;
Generates diagnosis target information indicating response characteristics of current or voltage measured by the measurement unit when the DC power output from the diagnosis target solar cell string is consumed in a pulse shape by being controlled by the consumption control unit Generating means for
An acquisition means for acquiring standard information indicating a response characteristic of current or voltage that can be measured at an output from a solar cell string having no defect when the DC power output by the solar cell string having no defect is consumed in a pulse form;
A calculation means for calculating a degree of deterioration of the diagnostic target solar cell string by comparing the diagnosis target information and the standard information;
A solar power generation system provided with the determination means which determines that there exists a malfunction in the solar cell string of the said diagnostic object when the said deterioration degree is larger than a threshold value.
A plurality of solar cell strings to be diagnosed are provided,
The solar power generation system further includes a circuit opening / closing unit capable of switching whether to connect each of the solar cell strings to be diagnosed independently to the conversion unit,
The photovoltaic power generation system according to claim 1, further comprising: an open / close control unit that controls whether or not each of the solar cell strings to be diagnosed is connected to the conversion unit by controlling the circuit open / close unit.
The consumption control means, when the open / close control means connects any one of the solar cell strings to be diagnosed to the converter, direct current power output from the solar cell string to be diagnosed is pulsed Control the conversion unit to consume
When the DC power output from any one of the solar cell strings to be diagnosed is consumed as a result of the consumption control unit controlling the conversion unit, the measuring unit has the solar cell string to be diagnosed The photovoltaic power generation system according to claim 2, wherein a current or a voltage at an output from said is measured.
The consumption control means consumes DC power output from the diagnostic target solar cell string in a pulsed manner when the open / close control unit connects the entire solar cell string to be diagnosed to the converter. Control the converter as follows,
When the DC power output from the entire diagnosis target solar cell string is consumed by the consumption control unit controlling the conversion unit, the measurement unit outputs from the diagnosis target solar cell string. The solar power generation system of Claim 2 or 3 which measures the electric current or voltage in.
A plurality of solar cell strings to be diagnosed are provided,
The solar power generation system further includes consumption means capable of independently pulsing DC power output from each of the diagnostic target solar cell strings,
The sunlight according to claim 1, wherein the consumption control means controls the consumption means so that the DC power output from each or all of the solar cell strings to be diagnosed is independently pulsed. Power generation system.
When the DC power output from each of the diagnosis target solar cell strings is consumed by the consumption control unit controlling the consumption unit, the measurement unit is configured to detect each of the diagnosis target solar cell strings. Measure the current or voltage at the output of
The generating unit generates a plurality of pieces of diagnosis target information indicating response characteristics of each current or each voltage measured by the measuring unit;
The calculation means calculates the degree of deterioration of each of the diagnostic target solar cell strings by comparing each of the diagnosis target information and the standard information,
6. The photovoltaic power generation according to claim 5, wherein when one of the deterioration degrees is larger than a threshold value, the determination unit determines that the solar cell string to be diagnosed corresponding to the deterioration degree larger than the threshold value is defective. system.
When the DC power output from the entire solar cell string to be diagnosed is consumed as a result of the consumption control unit controlling the consumption unit, the measuring unit is configured to output from the entire solar cell string to be diagnosed. Measure the current or voltage at the output,
The generating means generates diagnostic object information indicating a response characteristic of current or voltage measured by the measuring means,
The calculation means calculates the degree of deterioration of the entire diagnosis target solar cell string by comparing the diagnosis target information and the standard information,
The solar power generation system according to claim 5 or 6, wherein the determination unit determines that any of the solar cell strings to be diagnosed has a problem when the degree of deterioration is greater than a threshold value.
2. A protection unit that suppresses a current output from a diagnosis target solar cell string that is determined to have a defect when the determination unit determines that the diagnosis target solar cell string has a defect. The solar power generation system according to any one of 1 to 7.
Measuring means for measuring the current or voltage at the output from the solar cell string to be diagnosed;
Consumption control means for controlling consumption of DC power output by the solar cell string to be diagnosed;
Generating means for generating diagnostic object information indicating response characteristics of current or voltage measured by the measuring means when DC power output from the diagnostic target solar cell string is consumed by the consumption control means When,
An acquisition means for acquiring standard information indicating a response characteristic of current or voltage that can be measured at an output from a solar cell string having no defect when the DC power output by the solar cell string having no defect is consumed in a pulse form;
A calculation means for calculating a degree of deterioration of the diagnostic target solar cell string by comparing the diagnosis target information and the standard information;
A diagnostic apparatus for a solar power generation system, comprising: a determination unit that determines that the solar cell string to be diagnosed is defective when the degree of deterioration is greater than a threshold value.
DC power output from the solar cell string to be diagnosed is consumed in pulses,
When DC power output from the diagnostic target solar cell string is consumed in a pulsed manner, it generates diagnostic target information indicating current or voltage response characteristics measured at the output from the diagnostic target solar cell string. ,
Obtaining standard information indicating the response characteristics of current or voltage that can be measured at the output from the solar cell string without the defect when the DC power output by the solar cell string without the defect is consumed in the form of pulses,
By comparing the diagnosis object information and the standard information, the degree of deterioration of the diagnosis object solar cell string is calculated,
A diagnostic method for a photovoltaic power generation system, in which, when the degree of deterioration is greater than a threshold value, it is determined that the solar cell string to be diagnosed is defective.