JP4803314B1 - Solar cell inspection equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To inspect a solar battery panel or a solar battery cell without being affected by disturbance light and an external magnetic field while suppressing manufacturing cost.
SOLUTION: A solar cell panel SP in which a resistor is connected between electrodes via a conducting wire is placed on a stage 40. The light emitting element 50, the light emission signal supply circuit 65, and the light source driving circuit 66 irradiate light whose intensity changes at a predetermined cycle over the entire surface of the solar cell panel SP. The sensor signal extraction circuit 67 and the lock-in amplifier 68 detect a magnetic field that is generated when a current flows through the inspection object due to the light irradiation, and whose intensity changes with a period equal to the predetermined period. .
[Selection] Figure 1

Description

  The present invention relates to a solar cell inspection device that detects a defect of a solar cell panel configured by connecting solar cells or a plurality of solar cells.

  Since solar panels are used in environments exposed to high temperatures, low temperatures, rain, snow, etc., after a long period of time, the electrodes on the surface of the individual solar cells constituting the solar panel are soldered or conductive. There is a possibility that the location where the paste is connected or the location where the solar cells are connected is deteriorated. Therefore, it is necessary to inspect that the solar cell panel used for a long period of time does not have any connection failure or defect. In addition, immediately after manufacturing a solar battery cell or immediately after manufacturing a solar battery panel from a solar battery cell, the location where the electrodes on the surface of the solar battery cell are connected with solder or conductive paste or between the solar battery cells is connected. It is necessary to check that there is no connection failure at the connection point of the wiring.

  There are several methods for inspecting a solar battery cell or a solar battery panel composed of a plurality of solar battery cells. For example, as introduced in Patent Document 1 below, by a current generated by power generation, There is a method in which the magnetic field generated at each point is detected by a magnetic sensor, and the presence / absence of an abnormality is determined by comparing the distribution state of the magnetic field or the current distribution state that can be calculated from the magnetic field with a normal one. If it is this method, even if it is a photovoltaic cell, even if it is a photovoltaic panel (it is described as a photovoltaic module in the following patent documents 1), if the inspection object is made into a state where current flows by power generation, It is possible to accurately detect a defective portion such as a connection failure without contact.

JP 2010-171065 A

  However, since the solar cell generates power even by disturbance light other than light irradiated for inspection, there is a problem that inspection accuracy deteriorates when the disturbance light is not uniform in intensity at each part of the inspection object. . In addition, when dealing with this problem by eliminating the influence of ambient light, there is a problem that it is necessary to take the inspection object to the inspection place because the inspection place is limited like a dark room. is there. In addition, the magnetic sensor detects a magnetic field obtained by adding an external magnetic field such as a magnetic field generated by a geomagnetic field or an electric wire near the inspection target to a magnetic field generated by a current generated by power generation. Even when the strength is not uniform, there is a problem that the inspection accuracy deteriorates. Also, when dealing with this problem by eliminating the external magnetic field, the place to inspect the inspection object as far as possible from the inspection object such as the one that generates a magnetic field such as an electric wire in a magnetically shielded room There is a problem that the cost of equipment for inspection becomes high in addition to the trouble of bringing it into the factory.

  Furthermore, as described in Patent Document 1, when determining the presence or absence of abnormality by comparing the magnetic field distribution or the current distribution with a normal one, the inspection object is a constant size and the surface electrode is Must be in the same position. However, solar cells and solar panels have various sizes and structures, and it is extremely difficult to prepare standard inspection results corresponding to all inspection objects. For this reason, in the case where any solar battery cell or solar battery panel is an inspection object, it is necessary for the inspector to look at the magnetic field distribution or the current distribution to determine the defective part, and accurately detect the defective part. There is also a problem that it is difficult.

  The present invention has been made to solve this problem. Even when ambient light or an external magnetic field is present, the solar cell and the solar battery panel are inspected at a low cost without being affected by them. In addition, another object of the present invention is to provide a solar cell inspection apparatus capable of detecting a defective portion with high accuracy even for all types of solar cells and inspection objects of solar cell panels. In addition, in the description of each constituent element of the present invention below, in order to facilitate understanding of the present invention, reference numerals of corresponding portions of the embodiment are described in parentheses, but each constituent element of the present invention is The present invention should not be construed as being limited to the configurations of the corresponding portions indicated by the reference numerals of the embodiments.

In order to achieve the above object, the first feature of the present invention is that the surface of a solar cell panel (SP) or solar cell (SC) that is an inspection object in a state in which a resistor is connected between electrodes via a conductor. A light irradiating means (50, 65, 66) for irradiating light whose intensity changes at a predetermined cycle over the whole, and a magnetic field generated by a current flowing through the inspection object due to light irradiation by the light irradiating means. Magnetic field detection means (10, 20, 30, 40, 61 to 65, 67, 68) for detecting a magnetic field whose intensity changes at a period equal to the predetermined period at a plurality of locations facing the inspection object ; Based on the magnetic field detection results at a plurality of locations facing the inspection target detected by the magnetic field detection means, the current magnitude distribution at the plurality of locations of the inspection target or at a plurality of locations facing the inspection target. Distribution calculation means (70, S10 to S41, S100 to S124) for calculating the distribution of the strength of the magnetic field and the distribution of the current magnitude or the inspection object at a plurality of locations of the inspection object calculated by the distribution calculation means Based on the distribution of the magnetic field strength at a plurality of locations facing the object, the characteristics relating to the distribution of the magnitude of the current flowing in each part in the extending direction of the plurality of electrodes or the distribution of the strength of the magnetic field due to the current are shown. First characteristic value calculating means (S170 to S214, S220 to S256, S260, S264 to S276, S284 to S298) for calculating one characteristic value for each electrode is provided.

In this case, the light irradiating means may be composed of a light emitting element that emits light and a drive circuit that drives the light emitting element with a drive signal whose size changes at a predetermined period. Further, the magnetic field detection means includes a magnetic sensor means for detecting a magnetic field generated by current flowing through the inspection object by light irradiation at a plurality of locations facing the inspection object, and a magnetic field detected by the magnetic sensor means. The magnetic field component extracting means may extract a magnetic field component whose strength changes with a period equal to the predetermined period. The characteristic value in this case is, for example, a value obtained by dividing the average value of the current flowing through each part of one electrode by the average value of the current flowing through each part of all the electrodes, and the maximum current flowing through each part of one electrode. The difference between the value and the minimum value divided by the average value of the current flowing in each part of one electrode, and the standard deviation of the current flowing in each part of one electrode divided by the average value of the current flowing in each part of one electrode The difference between the maximum value and the minimum value of the average value of the current flowing in each part of all the electrodes in one solar cell is the average value of the current flowing in each part of all the electrodes in the one solar cell. It is the value divided. In this case, the current for calculating the first characteristic value can be replaced with a magnetic field corresponding to the current. Further, in this case, the first characteristic value is compared with a predetermined allowable value to automatically determine whether or not the inspection object is acceptable, or the first characteristic value is displayed to indicate whether the inspection object is acceptable to the operator. You may want to make a decision.

Further, a second feature of the present invention is that, in the first feature of the present invention, the first characteristic value calculating means is configured to measure the magnitude of current at a plurality of locations of the inspection object calculated by the distribution calculating means. A second characteristic representing the distribution of the magnitude of the current flowing between the plurality of electrodes or the distribution of the strength of the magnetic field due to the current based on the distribution or the distribution of the magnetic field strength at a plurality of locations facing the inspection object. The second characteristic value calculation means (S170 to S214, S220 to S256, S262, S264, S278 to S298) for calculating the characteristic value is used.

  In this case, as the second characteristic value, for example, the average value of the current flowing through each part between the plurality of electrodes in one solar battery cell, the current flowing through each part between the plurality of electrodes in all the solar battery cells, It is the value divided by the average value. In this case, the current for calculating the second characteristic value can be replaced with a magnetic field corresponding to the current. Furthermore, also in this case, the second characteristic value is compared with a predetermined allowable value to automatically determine the pass / fail of the inspection object, or the second characteristic value is displayed to show the inspection object to the operator. It is good to make a pass / fail decision.

In the first and second features of the present invention configured as described above, the intensity of light that irradiates the inspection object (solar cell panel or solar cell) to cause power generation is changed at a predetermined period, A magnetic field generated by a current flowing through the object to be inspected and whose intensity changes with a period equal to the predetermined period is detected at a plurality of locations. As a result, even if ambient light or an external magnetic field exists, the magnetic field can be detected at a plurality of locations facing the object to be inspected without being affected by these costs without being affected by these costs. And the distribution calculation means can obtain the distribution of the current magnitude at a plurality of locations of the inspection object or the distribution of the magnetic field strength at the plurality of locations facing the inspection object.

As a result of the experiment, the inventor has found that the first and second characteristic values greatly change from the normal state in a solar cell or solar panel in an abnormal state where there is a disconnection between electrodes, a contact failure between electrodes, or the like. Have found to be. Therefore, according to the first and second features of the present invention, it is possible to accurately detect an abnormal solar battery cell or solar battery panel having a disconnection between electrodes, a contact failure between electrodes, and the like.

  Another feature of the present invention is that display means (70, 72, S300, S310) for displaying the current magnitude distribution or the magnetic field strength distribution calculated by the distribution calculating means is further provided. It is in.

  According to this, the operator can visually recognize the distribution of the magnitude of the current at a plurality of locations of the inspection object or the distribution of the magnetic field strength at the plurality of locations opposite to the inspection object, from the distribution abnormality. It becomes possible to determine whether the inspection object is normal or abnormal.

It is a whole lineblock diagram of a solar cell inspection device concerning one embodiment of the present invention. It is a schematic perspective view which shows the specific example of the moving mechanism of the stage of FIG. 1, and a magnetic sensor. It is a detailed circuit block diagram of the magnetic sensor and sensor signal extraction circuit of FIG. FIG. 2 is a detailed circuit block diagram of the lock-in amplifier of FIG. 1. 3 is a flowchart showing the first half of a data acquisition program executed by the controller of FIG. It is a flowchart which shows the second half part of the said data acquisition program. 2 is a flowchart showing a head portion of an evaluation program executed by the controller of FIG. It is a flowchart which shows the part following FIG. 6A of the evaluation program performed by the controller of FIG. FIG. 6 is a flowchart showing a part following FIG. 6B of the evaluation program executed by the controller of FIG. It is a flowchart which shows the part following FIG. 6C of the evaluation program performed by the controller of FIG. It is a flowchart which shows the part following FIG. 6D of the evaluation program performed by the controller of FIG. It is a flowchart which shows the part following FIG. 6E of the evaluation program performed by the controller of FIG. FIG. 6 is a flowchart showing a part following FIG. 6F of the evaluation program executed by the controller of FIG. It is a flowchart which shows the part following FIG. 6G of the evaluation program performed by the controller of FIG. It is a schematic plan view which shows an example of a solar cell panel. It is a schematic sectional drawing of the photovoltaic cell of FIG. It is the schematic for demonstrating the connection state of the photovoltaic cell of FIG. It is explanatory drawing for demonstrating the scanning aspect of the solar cell panel by a magnetic sensor. It is explanatory drawing for demonstrating the change of the magnitude | size of the electric current of an electrode direction and the direction between electrodes when abnormality generate | occur | produces in the electrode of a photovoltaic cell. It is explanatory drawing for demonstrating the change of the magnitude | size of the electric current of an electrode direction and the direction between electrodes in case another abnormality generate | occur | produces in the electrode of a photovoltaic cell. It is explanatory drawing for demonstrating the change of the magnitude | size of the electric current of an electrode direction and the direction between electrodes when another abnormality generate | occur | produces in the electrode of a photovoltaic cell. It is a distribution map of the magnitude | size of the electric current which flows into a solar cell panel. It is explanatory drawing for demonstrating detection of the bus-bar electrode position of a solar cell panel. (A) is explanatory drawing for demonstrating the connection state of a bus-bar electrode and a back surface electrode via a connection line, (B) is a graph which shows the magnitude | size of the electric current which flows into a bus-bar electrode and a connection line. It is a figure which shows the display state of the current distribution of the photovoltaic cell in the state of FIG. 10A. It is a figure which shows the display state of the electric current distribution of the photovoltaic cell in the state of FIG. 10B. It is a figure which shows the display state of the electric current distribution of the photovoltaic cell in the state of FIG. 10C.

  Hereinafter, a solar cell inspection apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an overall schematic diagram of this solar cell inspection apparatus. The solar cell inspection apparatus includes a sensor support base 11 that supports and fixes the magnetic sensor 10. The sensor support base 11 is moved in the X direction (left and right direction in the drawing) by the X direction slide mechanism 20, and the Y direction slide mechanism 30. To move in the Y direction (perpendicular to the paper surface). As shown in detail in FIG. 2, the sensor support 11 is formed of a rectangular flat plate, and supports and fixes the magnetic sensor 10 on the upper surface. The sensor support 11 is supported by a rectangular moving member 21 that forms part of the X-direction slide mechanism 20. The moving member 21 is provided with an adjustment mechanism (not shown) that adjusts the vertical position of the magnetic sensor 10 by displacing the sensor support base 11 up and down. The position is adjusted in the vertical direction.

  On the lower surface of the moving member 21, a convex portion 21a having a predetermined width in the Y direction is provided. The convex portion 21a enters the groove 23a provided on the upper surface of the support member 23 extending in the X direction, and slides in the groove 23a in the X direction. A male screw 24 that extends in the X direction and penetrates the convex portion of the moving member 21 is accommodated in the groove 23 a of the support member 23. A nut (not shown) screwed into the male screw 24 is incorporated in the convex portion 21 a of the moving member 21, and the moving member 21 moves in the X direction by the rotation of the male screw 24. That is, the ball screw mechanism is constituted by the male screw 24 and the nut incorporated in the moving member 21. One end of the male screw 24 is connected to a rotation shaft of an X-direction motor 25 assembled to one end of the support member 23, and the other end of the male screw 24 is rotatably supported by the other end of the support member 23. Thereby, the male screw 24 rotates around the axis by the rotation of the X direction motor 25, and the moving member 21, the sensor support base 11, and the magnetic sensor 10 move in the X direction.

  Convex portions 23 b and 23 c having a predetermined width in the X direction are provided on the lower surface of the support member 23 in the vicinity of both ends in the X direction. These convex portions 23b and 23c enter the grooves 31a and 32a provided on the upper surfaces of the support members 31 and 32 respectively extending in the Y direction, and slide in the grooves 31a and 32a in the Y direction. ing. In the groove 31a of the support member 31, a male screw 33 extending in the Y direction and penetrating the convex portion 23b of the support member 23 is accommodated. A nut (not shown) screwed into the male screw 33 is incorporated in the convex portion 23 b of the support member 23, and the support member 23 is moved in the Y direction by the rotation of the male screw 33. That is, the ball screw mechanism is configured by the male screw 33 and the nut incorporated in the support member 23. One end of the male screw 33 is connected to a rotation shaft of a Y-direction motor 34 assembled to one end of the support member 31, and the other end of the male screw 33 is rotatably supported by the other end of the support member 31. Thereby, the male screw 33 rotates around the axis by the rotation of the Y direction motor 34, and the support member 23 moves in the Y direction together with the moving member 21, the sensor support 11 and the magnetic sensor 10.

  Moreover, this solar cell inspection apparatus is provided with a stage 40 for mounting the solar cell panel SP. The stage 40 has a rectangular frame 42 disposed above the support members 31 and 32 via connecting portions 41 a, 41 b, 41 c and 41 d extending upward from the respective end portions of the support members 31 and 32. have. The frame body 42 includes support portions 42a and 42b positioned above the support members 31 and 32, and support portions 42c and 42d that respectively connect both end portions of the support portions 42a and 42b. The support portions 42a, 42b, and 42c are provided with a placement portion that projects inward and places the solar cell panel SP. A movable mounting member 43 is assembled to the support portions 42a and 42b so as to be slidable in the Y direction at both ends. The moving mounting member 43 is also provided with a mounting portion that protrudes in the direction of the support member 42 and mounts the solar cell panel SP. And in the state which mounted solar cell panel SP on the support parts 42a, 42b, 42c of the frame 42, and the movement mounting member 43, the magnetic sensor 10 is located under the solar cell panel SP. .

  Returning again to the description of FIG. 1, a plurality of light emitting elements (LEDs) 50 are arranged on the frame 42 of the stage 40. The plurality of light emitting elements 50 are arranged in a matrix so that the entire solar cell panel SP is irradiated with light having a uniform light amount (that is, intensity) with the solar cell panel SP placed on the stage 40. ing.

  In the X direction motor 25, an encoder 25a that detects the rotation of the X direction motor 25 and outputs a rotation signal indicating the rotation is incorporated. This rotation signal is a pulse train signal that alternately switches between a high level and a low level each time the X-direction motor 25 rotates by a predetermined minute angle, and is phase-shifted by π / 2 to identify the rotation direction. The A phase signal and the B phase signal. The rotation signal is output to the X direction position detection circuit 61 and the X direction feed motor control circuit 62. The X-direction position detection circuit 61 counts up or down the number of pulses of the rotation signal in accordance with the rotation direction of the X-direction motor 25, and a sensor for the stage 40 (solar cell panel SP) by the X-direction motor 25 from the count value. The X-direction position of the support base 11 (that is, the X-direction position of the magnetic sensor 10) is detected, and the detected X-direction position is output to the X-direction feed motor control circuit 62 and a controller 70 described later. The X-direction feed motor control circuit 62 controls driving and stopping of the X-direction motor 25 according to instructions from the controller 70. When driving the X-direction motor 25, the feed motor control circuit 62 rotates the X-direction motor 25 at a predetermined rotation speed using a rotation signal from the encoder 25a.

  The initial setting of the count value in the X-direction position detection circuit 61 is performed according to an instruction from the controller 70 when the power is turned on. That is, the controller 70 instructs the X-direction feed motor control circuit 62 to move to the X-direction limit position corresponding to the initial position of the sensor support 11 and the X-direction position detection circuit 61 to perform initial setting when the power is turned on. In response to this instruction, the X-direction feed motor control circuit 62 drives the X-direction motor 25 to move the sensor support 11 to the X-direction limit position corresponding to the initial position. The X-direction position detection circuit 61 continues to input a rotation signal from the encoder 25a in the X-direction motor 25 while the sensor support base 11 is moving in the X direction. When the sensor support 11 reaches the X direction limit position corresponding to the initial position and the rotation of the X direction motor 25 stops, the X direction position detection circuit 61 detects the stop of the input of the rotation signal from the encoder 25a, The count value is reset to “0”. At this time, the X-direction position detection circuit 61 outputs a signal for stopping output to the X-direction feed motor control circuit 62, whereby the X-direction feed motor control circuit 62 outputs a drive signal to the X-direction motor 25. To stop. Thereafter, when the X direction motor 25 is driven, the X direction position detection circuit 61 counts up or down the number of pulses of the rotation signal in accordance with the rotation direction of the X direction motor 25, and based on the count value. Then, the X direction position of the sensor support 11 is calculated, and the calculated X direction position is continuously output to the X direction feed motor control circuit 62 and the controller 70.

  In the Y-direction motor 34, an encoder 34a that detects the rotation of the Y-direction motor 34 and outputs a rotation signal indicating the rotation is incorporated in the same manner as the X-direction motor 25. This rotation signal is output to the Y direction position detection circuit 63 and the Y direction feed motor control circuit 64. The Y-direction position detection circuit 63 counts up or counts down the number of pulses of the rotation signal in accordance with the rotation direction of the Y-direction motor 34, and the Y-direction position of the sensor support 11 by the Y-direction motor 34 (ie, the count value) The Y position of the magnetic sensor 10 is detected, and the detected Y direction position is output to the Y direction feed motor control circuit 64 and the controller 70. The Y-direction feed motor control circuit 64 controls the driving and stopping of the Y-direction motor 34 according to instructions from the controller 70 as in the case of the X-direction feed motor control circuit 62.

  The initial setting of the count value in the Y-direction position detection circuit 63 is performed according to an instruction from the controller 70 when the power is turned on. That is, the controller 70 instructs the Y-direction feed motor control circuit 64 to move to the Y-direction limit position corresponding to the initial position of the sensor support 11 and the Y-direction position detection circuit 63 at the time of power-on. In response to this instruction, the Y-direction feed motor control circuit 64 drives the Y-direction motor 34 to move the sensor support 11 to the Y-direction limit position corresponding to the initial position. The Y-direction position detection circuit 63 continues to input a rotation signal from the encoder 34a in the Y-direction motor 34 while the sensor support 11 is moving in the Y direction. When the sensor support base 11 reaches the Y-direction limit position corresponding to the initial position and the rotation of the Y-direction motor 34 stops, the Y-direction position detection circuit 63 detects the stop of input of the rotation signal from the encoder 34a, The count value is reset to “0”. At this time, the Y-direction position detection circuit 63 outputs a signal for stopping the output to the Y-direction feed motor control circuit 64, whereby the Y-direction feed motor control circuit 64 outputs a drive signal to the Y-direction motor 34. To stop. Thereafter, when the Y direction motor 34 is driven, the Y direction position detection circuit 63 counts up or down the number of pulses of the rotation signal in accordance with the rotation direction of the Y direction motor 34, and based on the count value. The Y-direction position of the sensor support 11 is calculated and the calculated Y-direction position is continuously output to the Y-direction feed motor control circuit 64 and the controller 70.

  The solar cell inspection apparatus further includes a light emission signal supply circuit 65, a light source drive circuit 66, a sensor signal extraction circuit 67, a lock-in amplifier 68, and a controller. The light emission signal supply circuit 65 includes a sine wave oscillator and a rectangular wave conversion circuit, and is controlled by the controller 70 to supply a sine wave signal oscillated by the sine wave oscillator to the light source drive circuit 66 as a light emission control signal. The light emission control signal is a signal that changes from positive to negative with reference to “0”, and the frequency thereof is, for example, about several tens of hertz to several hundreds of hertz. Further, the light emission signal supply circuit 65 generates a rectangular wave signal that changes positively and negatively around “0” in synchronization with the light emission control signal by converting the light emission control signal composed of the sine wave signal by the rectangular wave conversion circuit. Then, it is output to the lock-in amplifier 68 as a reference signal. The light source driving circuit 66 is also controlled by the controller 70 to control the light emitting element 50 to emit light according to the supplied light emission control signal. The light emitting element 50 irradiates the surface of the solar cell panel SP with a light emission intensity that changes in a sine wave shape in synchronization with the light emission control signal.

  Next, the magnetic sensor 10 will be described. As shown in FIG. 3, the magnetic sensor 10 includes an X-direction magnetic sensor 10A that detects a magnetic field in the X direction, and a Y-direction magnetic sensor 10B that detects a change in the magnetic field in the Y direction. The X-direction magnetic sensor 10A is constituted by a bridge circuit composed of resistors r11, r12, r13 and a magnetoresistive element MR1, and between the connection point of the resistors r11, r13 and the connection point of the resistor r12 and the magnetoresistive element MR1. In addition, voltages + V and −V are applied from a constant voltage supply circuit 67a, which will be described later, of the sensor signal extraction circuit 67. In the X-direction magnetic sensor 10A, a voltage between the connection point of the resistor r13 and the magnetoresistive element MR1 and the connection point between the resistors r11 and r12 is output as an X-direction magnetic detection signal. The values of the resistors r11, r12, r13 are the same and are equal to the resistance value of the magnetoresistive element MR1 when the magnetic field strength is “0”. As a result, the X direction magnetic field detection signal is a voltage that changes positively or negatively in proportion to the magnitude of the magnetic field in the X direction with reference to approximately “0” due to the positive or negative change in the X direction magnetic field with respect to approximately “0”. Signal.

  The Y-direction magnetic sensor 10B is composed of a bridge circuit composed of resistors r21, r22, r23 and a magnetoresistive element MR2, and between the connection point of the resistors r21, r22 and the connection point of the resistor r23 and the magnetoresistive element MR2. In addition, voltages + V and −V are applied from a constant voltage supply circuit 67 b described later of the sensor signal extraction circuit 67. In the Y direction magnetic sensor 10B, a voltage between the connection point of the resistor r22 and the magnetoresistive element MR2 and the connection point between the resistors r21 and r23 is output as a Y direction magnetic detection signal. The values of the resistors r21, r22, r23 are the same, and are equal to the resistance value of the magnetoresistive element MR2 when the magnetic field strength is “0”. As a result, the positive and negative changes in the magnetic field in the Y direction with respect to “0” as a reference cause the Y direction magnetic detection signal to change in positive and negative in proportion to the magnitude of the magnetic field in the Y direction with reference to “0”. Signal.

  The sensor signal extraction circuit 67 includes constant voltage supply circuits 67a and 67b and amplifiers 67c and 67d. The constant voltage supply circuits 67a and 67b supply constant voltages + V and −V to the X-direction magnetic sensor 10A and the Y-direction magnetic sensor 10B according to instructions from the controller 70. The amplifiers 67c and 67d amplify the X direction magnetic detection signal and the Y direction magnetic detection signal, respectively, and output the amplified signals to the lock-in amplifier 68.

  As shown in detail in FIG. 4, the lock-in amplifier 68 includes a high-pass filter 68a that inputs an X-direction magnetic detection signal supplied from the X-direction magnetic sensor 10A via an amplifier 67c, and an amplifier 67d from the Y-direction magnetic sensor 10B. And a high-pass filter 68b for inputting a Y-direction magnetic detection signal supplied via the. The high-pass filters 68a and 68b remove unnecessary components other than the signal component proportional to the strength of the magnetic field included in the X-direction magnetic detection signal and the Y-direction magnetic detection signal, and change the signal around the ground level. To.

  The output of the high pass filter 68a is supplied to the phase detection circuits 68d and 68e via the amplifier 68c. The phase detection circuits 68d and 68e are each configured by a multiplier. The phase detection circuit 68d multiplies the X direction magnetic detection signal supplied via the high pass filter 68a and the amplifier 68c by the reference signal from the light emission signal supply circuit 65 and outputs the result to the low pass filter 68f. The phase detection circuit 68e adds a delayed reference signal obtained by delaying the phase of the reference signal from the light emission signal supply circuit 65 by 90 degrees by the phase shift circuit 68g to the X-direction magnetic detection signal supplied via the high-pass filter 68a and the amplifier 68c. Multiply and output to low pass filter 68h. Thus, a component synchronized with the light emission control signal (reference signal) of the X-direction magnetic detection signal is supplied to the low-pass filter 68f, and the low-pass filter 68f performs low-pass filtering on the supplied component signal to A signal indicating the magnitude of the component synchronized with the light emission control signal is output. The low-pass filter 68h is supplied with a component synchronized with a signal (delayed reference signal) delayed in phase by 90 degrees from the light emission control signal of the X-direction magnetic detection signal. The low-pass filter 68h performs low-pass filter processing on the supplied component signal. Then, a signal indicating the magnitude of the component synchronized with the signal delayed by 90 degrees from the light emission control signal of the X direction magnetic detection signal is output.

  The output of the high pass filter 68b is supplied to the phase detection circuits 68j and 68k through the amplifier 68i. Low-pass filters 68m and 68n are connected to the phase detection circuits 68j and 68k. The phase detection circuits 68j and 68k and the low-pass filters 68m and 68n are configured similarly to the phase detection circuits 68d and 68e and the low-pass filters 68f and 68h described above. As a result, a component synchronized with the light emission control signal (reference signal) of the Y-direction magnetic detection signal is supplied to the low-pass filter 68m, and the low-pass filter 68m performs low-pass filter processing on the supplied component signal to generate the Y-direction magnetic detection signal. A signal indicating the magnitude of the component synchronized with the light emission control signal is output. The low-pass filter 68n is supplied with a component synchronized with a signal (delayed reference signal) delayed in phase by 90 degrees from the light emission control signal of the Y-direction magnetic detection signal. The low-pass filter 68n performs low-pass processing on the supplied component signal A signal indicating the magnitude of the component synchronized with the signal delayed by 90 degrees from the light emission control signal of the Y direction magnetic detection signal is output. The low pass filters 68f, 68h, 68m, and 68n are connected to A / D converters 68o, 68p, 68q, and 68r, respectively. The A / D converters 68o, 68p, 68q, 68r respectively A / D convert the signals from the low-pass filters 68f, 68h, 68m, 68n and supply them to the controller 70 at predetermined time intervals.

  Returning to the description of FIG. 1 again, the controller 70 is an electronic control unit including a microcomputer including a CPU, a ROM, and a RAM, a storage device such as a hard disk and a nonvolatile memory, an input / output interface, and the like. The controller 70 controls the operation of this solar cell inspection apparatus by executing the data acquisition program of FIGS. 5A and 5B and the evaluation program of FIGS. 6A to 6H stored in the storage device. Connected to the controller 70 are an input device 71 for an operator to instruct various parameters, processing, and the like, and a display device 72 for visually informing the operator of the operation status and the like.

  Next, the solar cell panel SP will be described. As shown in FIG. 7, in the solar battery panel SP, a large number of solar battery cells SC arranged in a matrix are fixed on a substrate 80. In the present embodiment, it is assumed that tmax solar cells SC are arranged in the X direction and smax solar cells SC in the Y direction. Each solar cell SC has various structures. As shown in the enlarged schematic cross-sectional view of FIG. 8A, the back electrode 81, the p + type layer 82, the p type layer 83, the n type layer 84, and the antireflection film 85 are provided. It is configured by stacking. The solar cell SC includes a plurality of grid electrodes (light-receiving surface electrodes) 86 that are formed in a flat and long shape and are arranged in the horizontal direction at equal intervals, and the lower end surface of the grid electrode 86 is an n-type layer 84. And the upper end surface protrudes upward. A pair of bus bar electrodes 87 formed in a bar shape are connected to the upper end surfaces of the plurality of grid electrodes 86 at their lower surfaces.

  Then, smax solar cells SC arranged in the Y direction are connected in series, and tmax sets of solar cells SC composed of smax solar cells SC connected in series are connected in parallel. ing. In this case, in the smax solar cells SC arranged in the Y direction, the bus bar electrode 87 of the adjacent solar cell SC is connected to the back electrode 81 via the connection line 88 as shown in FIG. 8B. I have to. In addition, in tmax sets of solar cells SC group composed of smax solar cells SC connected in series, specifically, the bus bar electrodes 87 of the solar cells SC at one end in the Y direction of the solar cells SC group. Are connected in common by the connection line 89a, and the back electrode 81 of the solar cell SC at the other end in the Y direction is connected in common by the connection line 89b. Output terminals 90a and 90b are provided at the output ends of the connection lines 89a and 89b. In addition, in the connection method of the photovoltaic cells SC, a plurality of rows of photovoltaic cells SC in the X direction may be connected in series.

  Next, the operation of the solar cell inspection apparatus configured as described above will be described. As shown in FIG. 7, the worker connects a small resistance Rcs (for example, a resistance of about 5 ohms) between the output terminals 90a and 90b of the solar cell panel SP to be inspected via the conducting wires L1 and L2. Then, it is placed on the frame body 42 of the stage 40. In this case, the corner in the vicinity of the position that is the origin of the XY plane of the solar cell panel SP (the position where the variables n and m are both “1” in the program described later) is one of the corners of the frame body 42 ( In the present embodiment, the solar cell panel SP is fixed by moving the moving mounting member 43 in accordance with the corner located in the lower right of FIG. The reason why the resistor Rcs is connected is to allow a current generated by the power generation of the solar cell SC to flow through the solar cell SC by light irradiation using the light emitting element 50. In this state, when the power supply of the solar cell inspection apparatus is turned on, as described above, the X direction feed motor control circuit 62 and the Y direction feed motor control circuit 64 cause the sensor support member 11 (that is, magnetic The sensor 10) is moved to the limit positions in the X direction and the Y direction, and the X direction position detection circuit 61 and the Y direction position detection circuit 63 set the detected X direction position and Y direction position to initial values.

  Thereafter, the operator operates the input device 71 to input parameters necessary for the measurement of the solar cell panel SP. In this case, necessary parameters include the numbers tmax and smax of the solar cells SC in the X direction and the Y direction, the lengths of the solar cells SC in the X direction and the Y direction, and the bus bar electrodes 87 in the solar cells SC. (2 in the solar cell SC shown in FIG. 7). The input parameters are stored in the controller 70. Further, parameters such as an X-direction end position Xmax, a Y-direction end position Ymax, a value Nn, a value Nm, and a value ce used in a data processing program and an evaluation program described later are calculated from the input parameters and stored. Is done.

  Next, the operator causes the controller 70 to start executing the data acquisition program of FIGS. 5A and 5B by operating the input device 71. That is, the controller 70 is instructed to start measurement of the solar cell panel SP. In response to this instruction, the controller 70 starts execution of the data acquisition program in step S10 in FIG. 5A, initializes the variable n to “0” in step S11, and sets the variables m and a to “ Initial setting is “1”. The variables n and m are variables indicating the scanning position of the magnetic sensor 10 with respect to the solar cell panel SP. As shown in FIG. 9, the magnetic sensor 10 is first controlled to move by a predetermined minute value ΔX in the X direction from the start position represented by the initial value Xs to the end position represented by the end value Xmax. The When the end position in the X direction is reached, the magnetic sensor 10 is controlled to move by a predetermined minute value ΔY in the Y direction, and then controlled to move by a minute value ΔX from the end position in the X direction to the start position in the X direction. The Again, the magnetic sensor 10 is controlled to move by a minute value ΔY in the Y direction, and is controlled to move by a minute value ΔX from the start position to the end position in the X direction. Thus, the magnetic sensor 10 moves in the Y direction while reciprocating in the X direction, and scans the solar cell panel SP. Note that the minute values ΔX and ΔY are extremely small compared to the length and width of the solar battery cell SC. The variable a represents a state where the center position of the magnetic sensor 10 is moved to the X axis direction positive side by “1”, and the center position of the magnetic sensor 10 is moved to the X axis direction negative side by “−1”. It represents the state. Hereinafter, the center position of the magnetic sensor 10 is referred to as an inspection position.

  After the process of step S11, the controller 70 moves the magnetic sensor 10 in the X-axis direction with respect to the X-direction feed motor control circuit 62 in step S12, and the inspection position is represented by the initial value Xs in the X-axis direction. And the Y-direction feed motor control circuit 64 moves the magnetic sensor 10 in the Y-axis direction so that the inspection position becomes the initial position represented by the initial value Ys in the Y-axis direction. To instruct. In response to this instruction, the X-direction feed motor control circuit 62 inputs the X-direction detection position (the inspection position in the X-axis direction, that is, the measurement position) from the X-direction position detection circuit 61, and the X-direction detection position is the initial value. The X direction motor 25 is driven and controlled until it coincides with Xs. The Y-direction feed motor control circuit 64 inputs the Y-direction detection position (inspection position in the Y-axis direction, that is, the measurement position) from the Y-direction position detection circuit 63, and continues until the Y-direction detection position matches the initial value Ys. The drive of the motor 34 is controlled.

  After the process of step S12, the controller 70 instructs the operation of the light emission signal supply circuit 65 to start in step S13. In response to this instruction, the light emission signal supply circuit 65 supplies a sinusoidal light emission control signal to the light source drive circuit 66, and supplies a rectangular wave reference signal synchronized with the light emission control signal to the lock-in amplifier 68. start. Next, the controller 70 instructs the light source driving circuit 66 to start operating in step S14. In response to this instruction, the light source driving circuit 66 supplies the light emitting element 50 with a drive control signal that changes in a sine wave shape according to the supplied light emission control signal, and starts light emission control of the light emitting element 50. Next, the controller 70 instructs the operation start of the sensor signal extraction circuit 67 in step S15. In response to this instruction, the constant voltage supply circuits 67a and 67b in the sensor signal extraction circuit 67 start to supply the constant voltage signals + V and −V to the X direction magnetic sensor 10A and the Y direction magnetic sensor 10B. As a result, the X direction magnetic detection signal and the Y direction magnetic detection signal from the X direction magnetic sensor 10A and the Y direction magnetic sensor 10B start to be supplied to the lock-in amplifier 68 via the amplifiers 67c and 67d, respectively.

  The X direction magnetic detection signal and the Y direction magnetic detection signal will be described. By the light emission control of the light emitting element 50, the light emitting element 50 uniformly irradiates the entire surface of the solar cell panel SP while changing the light emission intensity in a sine wave shape in synchronization with the light emission control signal. With this light irradiation, the solar cell panel SP starts to generate electric power according to the light emission intensity. Due to the power generation, a current flows on the surface of each solar cell SC, and a current flows through the electrodes to the conductors L1 and L2 and the resistor Rcs. A magnetic field is generated. Then, the X direction magnetic sensor 10A starts outputting a voltage proportional to the magnitude of the magnetic field H in the X direction as an X direction magnetic detection signal. Further, the Y direction magnetic sensor 10B starts to output a voltage proportional to the magnitude of the magnetic field H in the Y direction as a Y direction magnetic detection signal. These X direction magnetic detection signal and Y direction magnetic detection signal are signals that change sinusoidally because the light emission intensity of the light emitting element 50 changes sinusoidally. However, the phases of the X-direction magnetic detection signal and the Y-direction magnetic detection signal are slightly different from those of the sinusoidal light emission control signal for driving and controlling the light emitting element 50.

  In the lock-in amplifier 68, the input X-direction magnetic detection signal is supplied to the phase detection circuits (multipliers) 68d and 68e via the high-pass filter 68a and the amplifier 68c, and the input Y-direction magnetic detection signal. Are supplied to phase detection circuits (multipliers) 68j and 68k through a high-pass filter 68b and an amplifier 68i, respectively. A rectangular wave reference signal from the light emission signal supply circuit 65 is supplied to the phase detection circuits 68d and 68j. The phase detection circuits 68e and 68k are supplied with a delayed reference signal obtained by delaying the phase of the reference signal by 90 degrees by the phase shift circuit 68g. Then, the phase detection circuits 68d and 68e multiply the X direction magnetic detection signal supplied via the amplifier 68c by the reference signal and the delayed reference signal, respectively, and the multiplied signals are converted to A / A via the low pass filters 68f and 68h. The signals are supplied to D converters 68o and 68p, respectively. The phase detection circuits 68j and 68k multiply the Y direction magnetic detection signal supplied via the amplifier 68c by the reference signal and the delayed reference signal, respectively, and A / D convert the multiplied signals via the low pass filters 68m and 68n. It supplies to the devices 68q and 68r, respectively.

  Here, the low-pass filters 68f, 68h, 68m, and 68n function to output a signal that represents the magnitude of the component of the supplied signal, that is, a signal that represents the magnitude proportional to the amplitude of the sinusoidal signal. Therefore, the A / D converter 68o is supplied with a signal indicating the magnitude of the signal component synchronized with the reference signal (that is, the light emission control signal) of the X direction magnetic detection signal. The A / D converter 68p is supplied with a signal representing the magnitude of the signal component whose phase is delayed by 90 degrees from the reference signal of the X direction magnetic detection signal. A signal representing the magnitude of the signal component synchronized with the reference signal of the Y-direction magnetic detection signal is supplied to the A / D converter 68q. The A / D converter 68r is supplied with a signal representing the magnitude of the signal component whose phase is delayed by 90 degrees from the reference signal of the Y-direction magnetic detection signal. The A / D converters 68o, 68p, 68q, and 68r sample the supplied signals at predetermined time intervals, perform A / D conversion, and supply the A / D converted sampling data to the controller 70. Therefore, the sampling data representing the magnitude of each signal component every predetermined time is supplied to the controller 70 every predetermined time.

  After the processing in step S15, the controller 70 adds the variable a to the variable n in step S16. In this case, since the variable n before the process of step S16 is “0” and the variable a is “1”, the variable n is changed to “1”. After the process of step S16, the controller 70 fetches the sampling data supplied from the A / D converters 68o, 68p, 68q, 68r of the lock-in amplifier 68 in step S17, and fetches the sampling data fetched in step S18. It is determined whether or not the number of sampling data has reached a predetermined number K. The predetermined number K is set to a value representing the number of sampling data of several to several tens, for example. If the number of sampling data does not reach the predetermined number K, the controller 70 makes a “No” determination at step S18, and then from the A / D converters 68o, 68p, 68q, 68r to the next at step S17. Takes output sampling data. When the number of sampling data fetched from the A / D converters 68o, 68p, 68q, 68r reaches a predetermined number K, the controller 70 determines “Yes” in step S18, and after step S19. Execute the process. The sampling data acquired in step S17 is stored in the RAM as a sampling data group specified by the variables n and m.

  Specifically, a predetermined number K of sampling data fetched from the A / D converter 68o, that is, a predetermined number K of data representing the magnitude of the signal component synchronized with the reference signal of the X-direction magnetic detection signal is the sampling data. The group Sx1 (n, m) is stored in the RAM. The predetermined number K of sampling data fetched from the A / D converter 68p, that is, the predetermined number K of data representing the magnitude of the signal component synchronized with the delayed reference signal of the X-direction magnetic detection signal is the sampling data group Sx2 (n , m) is stored in the RAM. A predetermined number K of sampling data fetched from the A / D converter 68p, that is, a predetermined number K of data representing the magnitude of the signal component synchronized with the reference signal of the Y-direction magnetic detection signal, is a sampling data group Sy1 (n, m) is stored in the RAM. The predetermined number K of sampling data taken from the A / D converter 68r, that is, the predetermined number K of data representing the magnitude of the signal component synchronized with the delayed reference signal of the Y-direction magnetic detection signal, is the sampling data group Sy2 (n , m) is stored in the RAM. In this case, the variables n and m are both “1”.

  After the processes in steps S17 and S18, the controller 70 determines whether or not the variable a is “1” in step S19. Since the variable a is initially set to “1”, in this case, the controller 70 determines “Yes” in step S19, and in step S20, the value Xs + n · ΔX is the end value Xmax in the X-axis direction. It is judged whether it is larger than. The value Xs + n · ΔX is a value obtained by multiplying the predetermined value ΔX representing the scanning interval in the X-axis direction by the variable n and adding the initial value Xs, and the next detected position in the X-axis direction (scanning position in the X-axis direction, that is, It is a value (see FIG. 9) representing the (measurement position). If the value Xs + n · ΔX is equal to or less than the end value Xmax, the controller 70 makes a “No” determination at step S20, and sets the center position of the magnetic sensor 10 to the X-direction feed motor control circuit 62 at step S21. Instructs to move to the X axis direction positive side. Thereby, the X-direction feed motor control circuit 62 operates the X-direction motor 25 to start moving the center position of the magnetic sensor 10 to the positive side in the X-axis direction.

  Next, the controller 70 inputs the X direction position from the X direction position detection circuit 61 in step S22, and whether or not the X direction position input in step S23 has reached the next detection position in the X axis direction. That is, it is determined whether or not the value indicating the position in the X direction is equal to or greater than the value Xs + n · ΔX. The controller 70 continues to determine “No” in step S23 until the X-direction position input from the X-direction position detection circuit 61 reaches the detection position in the next X-axis direction, and the processing in steps S22 and S23. Repeatedly. When the X-direction position input from the X-direction position detection circuit 61 reaches the detection position in the next X-axis direction, the controller 70 determines “Yes” in step S23, and in step S24, the X-direction feed motor control circuit. 62 is instructed to stop the movement of the magnetic sensor 10 toward the positive side in the X-axis direction. Accordingly, the X-direction feed motor control circuit 62 stops the operation of the X-direction motor 25 and stops the movement of the magnetic sensor 10 to the positive side in the X-axis direction. As a result, the magnetic sensor 10 starts detecting the magnetic field of the solar cell panel SP using the X-axis direction position represented by the value Xs + n · ΔX and the Y-axis direction initial value Ys as the detection position of the magnetic sensor 10.

  After the process of step S24, the controller 70 returns to step S16, adds the variable a (in this case, a = 1) to the variable n by the process of step S16, and obtains the sampling data of the above-described steps S17 and S18. Execute capture processing. By the processing of these steps S17 and S18, sampling data by magnetic field detection of the magnetic sensor 10 having the X-axis direction position represented by the value Xs + (n−1) · ΔX and the Y-axis direction initial value Ys as the detection position is obtained. Newly stored in RAM. Specifically, a predetermined number K of sampling data representing the magnitudes of signal components synchronized with the reference signal and the delayed reference of the X direction magnetic detection signal are sampled data groups Sx1 (n, m), Sx2 (n, m ) Is stored in the RAM. A predetermined number K of sampling data representing the magnitudes of the signal components synchronized with the reference signal and the delayed reference signal of the Y-direction magnetic detection signal are sampled data groups Sy1 (n, m) and Sy2 (n, m). Stored in RAM. In this case, the variable n is “2” and the variable m is “1”.

  Then, the controller 70 uses the magnetic sensor 10 until the value Xs + n · ΔX representing the next detection position in the X-axis direction (scanning position in the X-axis direction) becomes larger than the end value Xmax. The detection position is moved to the X axis direction positive side by a predetermined value ΔX, and sampling data is taken in while increasing the variable n by “1”. When the value Xs + n · ΔX representing the next detected position in the X-axis direction becomes larger than the end value Xmax, the controller 70 determines “Yes” in step S20 and advances the program to step S30 in FIG. 5B. . In this state, the sampling data groups Sx1 (n, m), Sx2 (n, m), Sy1 (n, m), Sy2 (n, m) (n = 1, 2, 3... Nmax, m = 1 ) Is stored in the RAM. The value nmax is a value of the variable n related to the sampling data group at the detection position immediately before the end value Xmax, and represents the number of detection positions in the X-axis direction.

  In step S30, the controller 70 instructs the Y-direction feed motor control circuit 64 to move the detection position by the magnetic sensor 10 to the Y axis direction positive side. Thereby, the Y-direction feed motor control circuit 64 operates the Y-direction motor 34 to start moving the detection position by the magnetic sensor 10 to the Y axis direction positive side. Next, the controller 70 inputs the Y-direction position from the Y-direction position detection circuit 63 in step S31, and whether the Y-direction position input in step S32 has reached the next detection position Ys + m · ΔY in the Y-axis direction. Determine whether or not. The next detected position Ys + m · ΔY in the Y-axis direction is the initial value Ys by multiplying a predetermined value ΔY representing the scanning interval in the Y-axis direction by a variable m, similarly to the next detected position Xs + n · ΔX in the X-axis direction. (See FIG. 9). Then, until the Y-direction position input from the Y-direction position detection circuit 63 reaches the next detection position in the Y-axis direction, the controller 70 continues to determine “No” in step S32, and the processing in steps S31 and S32 Repeatedly. When the Y-direction position input from the Y-direction position detection circuit 63 reaches the next detection position in the Y-axis direction, the controller 70 determines “Yes” in step S32, and the Y-direction feed motor control circuit in step S33. 64 is instructed to stop the movement of the magnetic sensor 10 toward the positive side in the Y-axis direction. Thereby, the Y-direction feed motor control circuit 64 stops the operation of the Y-direction motor 34 and stops the movement of the detection position of the magnetic sensor 10 to the Y axis direction positive side. As a result, the magnetic sensor 10 is represented by a value Xs + (n−1) · ΔX (= Xs + (nmax−1) · ΔX) and a value Ys + m · ΔY (= Ys + ΔY). The detection of the magnetic field in the vicinity of the surface of the solar cell panel SP is started using the position in the Y-axis direction as the detection position.

  After the processing of step S33, the controller 70 inputs the Y-direction position from the Y-direction position detection circuit 63 in step S34, and the scanning in the Y-axis direction in which the input Y-direction position is represented by the end value Ymax is completed. It is determined whether or not the position has been exceeded. If the position in the Y direction does not exceed the scanning end position, the controller 70 determines “No” in step S34, adds “1” to the variable m in step S35, and sets the variable a in step S36. Multiply by “−1”. In this case, the variable m becomes “2” by the process of step S35, and the variable a becomes “−1” by the process of step S36. The variable n is kept at the value nmax. After the process of step S36, the controller 70 returns to step S17, and each of the K sampling data groups Sx1 (nmax, 2), Sx2 (nmax, 2), Sy1 (nmax) from the processes of steps S17 and S18. , 2), Sy2 (nmax, 2) are taken from the lock-in amplifier 68 and stored.

  After the processing in steps S17 and S18, the controller 70 determines whether or not the variable a is “1” in step S19. In this case, since the variable a is set to “−1” by the process of step S36, the controller 70 determines “No” in step S19, and in step S25, the value Xs + (n−2). ) · ΔX is determined whether or not it is smaller than the initial value Xs in the X-axis direction. In this case, the variable n is nmax, and the value Xs + (n−2) · ΔX is the value in the next X-axis direction when the second detection position from the right end of the solar cell panel SP in FIG. 9 is moved to the left side. This is a value representing the detection position (scanning position in the X-axis direction). If the value Xs + (n−2) · ΔX is not smaller than the initial value Xs, the controller 70 determines “No” in step S25, and in step S26, instructs the X-direction feed motor control circuit 62 to An instruction is given to move the detection position by the sensor 10 to the X axis direction negative side. Thereby, the X-direction feed motor control circuit 62 starts to move the detection position by the magnetic sensor 10 to the X-axis direction negative side by operating the X-direction motor 25.

  Next, the controller 70 inputs the X direction position from the X direction position detection circuit 61 in step S27, and whether or not the X direction position input in step S28 has reached the next detection position in the X axis direction, That is, it is determined whether or not the value indicating the position in the X direction is equal to or less than the value Xs + (n−2) · ΔX. The controller 70 continues to determine “No” in step S28 until the X-direction position input from the X-direction position detection circuit 61 reaches the detection position in the next X-axis direction, and the processing in steps S27 and S28. Repeatedly. When the X-direction position input from the X-direction position detection circuit 61 reaches the detection position in the next X-axis direction, the controller 70 determines “Yes” in step S28, and in step S29, the X-direction feed motor control circuit. 62 is instructed to stop the movement of the detection position to the negative side in the X-axis direction. Thereby, the X-direction feed motor control circuit 62 stops the operation of the X-direction motor 25 and stops the movement of the detection position by the magnetic sensor 10 to the negative side in the X-axis direction. As a result, the magnetic sensor 10 has an X-axis direction position represented by a value Xs + (n−2) · ΔX (= Xs + (nmax−2) · ΔX), and a value Ys + (m−1) · ΔYs (= Ys + ΔYs). ) To detect the magnetic field in the vicinity of the surface of the solar panel SP.

  After the process of step S29, the controller 70 returns to step S16, adds the variable a (in this case, a = -1) to the variable n by the process of step S16, and samples the sampling data of the above-described steps S17 and S18. Execute the import process. By the processing in steps S17 and S18, the position in the X-axis direction represented by the value Xs + (n−2) · ΔX (= Xs + (nmax−2) · ΔX) before the processing in step S16, and the value Ys + ( m−1) · YS (= Ys + ΔYs) The K sampling data groups Sx1 (n, m), Sx2 (n, m), Sy1 (n, m) each having the position in the Y-axis direction as the detection position ), Sy2 (n, m) are captured and stored. Note that the variable n regarding the sampling data group to be captured and stored is the value nmax−1, and the variable m is “2”.

  Then, the controller 70 performs steps S16 to S19 and S25 until the value Xs + (n−2) · ΔX representing the next detection position in the X-axis direction (scanning position in the X-axis direction) becomes smaller than the initial value Xs. By the processing of S29, the detection position is moved to the X axis direction negative side by a predetermined value ΔX, and the sampling data is taken in while the variable n is decreased by “1”. When the value Xs + (n−2) · ΔX representing the next detected position in the X-axis direction becomes smaller than the initial value Xs, the controller 70 determines “Yes” in step S25, and the step of FIG. 5B Proceed to S30. Note that the variable n at this time is “1”. In this state, the sampling data groups Sx1 (n, m), Sx2 (n, m), Sy1 (n, m), Sy2 (n, m) (n = 1, 2, 3... Nmax, m = 1), sampling data groups Sx1 (n, m), Sx2 (n, m), Sy1 (n, m), Sy2 (n, m) (n = 1, 2, 3... Nmax, m = 2) is stored in the RAM.

  The controller 70 operates the Y direction motor 34 and moves the detection position by the magnetic sensor 10 to the next Y axis direction detection position Ys + m · ΔY by the processing of steps S30 to S33 described above. As a result, the magnetic sensor 10 uses the initial position in the X-axis direction represented by the initial value Xs and the position in the Y-axis direction represented by the value Ys + m · ΔY (= Ys + 2 · ΔY) as the detection position. Start detecting the magnetic field in the vicinity of the surface. Next, on the condition that the Y-direction position detected by the Y-direction position detection circuit 63 does not exceed the end position, the controller 70 determines “No” in step S34, and step S35. In step S36, “1” is added to the variable m, and in step S36, the variable a is multiplied by “−1”. In this case, the variable m becomes “3” by the process of step S35, and the variable a becomes “1” by the process of step S36. The variable n is kept at “1”. After the process of step S36, the controller 70 returns to step S17, and from the processes of steps S17 and S18, the K sampling data groups Sx1 (1,3), Sx2 (1,3), Sy1 (1 , 3) and Sy2 (1, 3) are taken from the lock-in amplifier 68 and stored.

  After the processing in steps S17 and S18, the controller 70 determines whether or not the variable a is “1” in step S19. In this case, since the variable a is set to “1” by the process of step S36, the controller 70 determines “Yes” in step S19, and the processes of steps S20 to S24 and S16 to S19 described above. Are repeatedly executed until the value Xs + n · ΔX becomes larger than the end value Xmax. Thereby, the detection position by the magnetic sensor 10 is scanned to the positive side in the X-axis direction, and the sampling data group Sx1 (n, m), Sx2 (n, m), Sy1 (n, m), Sy2 (n, m) (N = 1, 2, 3... Nmax, m = 3) is newly stored in the RAM.

  When the variable m is set to “3” and the scanning of the detection position of the magnetic sensor 10 to the positive side in the X-axis direction is completed, the processes of steps S30 to S36 are executed by the determination process of step S20. The position detected by the magnetic sensor 10 is changed to the next position in the Y-axis direction, and the variables m and a are changed. Then, by the processing of steps S16 to S19 and S25 to S29 described above, the detection position by the magnetic sensor 10 is scanned to the negative side in the X-axis direction, and sampling data groups Sx1 (n, m), Sx2 (n, m), Sy1. (n, m), Sy2 (n, m) (n = 1, 2, 3... nmax, m = 4) are newly stored in the RAM.

  By such processing of steps S16 to S36, the detection position by the magnetic sensor is scanned so as to reciprocate in the X-axis direction, and is scanned to the Y-axis direction positive side, and detected by the Y-direction position detection circuit 63. When the direction position becomes larger than the end value Ymax, the controller 70 determines “Yes” in step S34, and executes the processing after step S37. In this state, K sampling data groups Sx1 (n, m), Sx2 (n, m), Sy1 (n, m), Sy2 (n, m) (n = 1 to nmax, m = 1 to mmax) are stored. The value mmax is the value of the variable m related to the sampling data group at the detection position immediately before the end value Ymax, and represents the number of detection positions in the Y-axis direction.

  The controller 70 instructs the sensor signal extraction circuit 67 to stop operating in step S37, instructs the light source drive circuit 66 to stop operating in step S38, and instructs the light emission signal supply circuit 65 to stop operating in step S39. . The operation of the light emitting element 50, the light emission signal supply circuit 65, the light source drive circuit 66, the sensor signal extraction circuit 67, the lock-in amplifier 68, and the magnetic sensor 10 is stopped by these operation stop instructions. After the process of step S39, the controller 70 instructs the X-direction position detection circuit 61 and the X-direction feed motor control circuit 62 to move the sensor support 11 to the X-direction drive limit position in step S40. The Y direction position detection circuit 63 and the Y direction feed motor control circuit 64 are instructed to move the sensor support 11 to the Y direction drive limit position, and the execution of the data acquisition program is terminated in step S41. The X-direction feed motor control circuit 62 moves the sensor support 11 to the X-direction drive limit position in cooperation with the X-direction position detection circuit 61 as in the initial setting described above. As described above, the Y-direction feed motor control circuit 64 moves the sensor support 11 to the Y-direction drive limit position in cooperation with the Y-direction position detection circuit 63.

  Next, a predetermined number K of sampling data groups Sx1 (n, m), Sx2 (n, m), Sy1 (n, m), Sy2 (n, m) (n = 1 to 1) acquired by the data acquisition program. nmax, m = 1 to mmax), a method for evaluating the solar cell panel SP will be described. In this case, the operator operates the input device 71 to cause the controller 70 to execute the evaluation programs of FIGS. 6A to 6H. In this evaluation program, whether or not the solar cell panel SP is accepted or rejected, or the operator determines whether or not the solar cell panel SP is acceptable, the magnitude of the current at each point of the XY coordinates of the solar cell panel SP. An image of the current distribution as the direction is displayed on the display device. Therefore, before describing the evaluation program, the current distribution when an abnormality occurs in the electrode of the solar battery cell SC will be described.

  FIG. 10A shows the experimental results of the current magnitude distribution when one of the electrodes of the solar battery cell SC is disconnected. In (A), focusing on one solar cell SC, a resistor is connected between the pair of bus bar electrodes 87 and 87 and the pair of back surface electrodes 81 and 81 (rear surface electrode side terminals 81a and 81a are shown). An equivalent circuit is shown. The current direction is positive in the upward direction and right direction in the figure. In this state, the magnitude of the current flowing through the bus bar electrode 87 on the left side of the figure changes as follows at the position in the Y direction. First, when no disconnection occurs, the distribution of the magnitude of the current flowing through the bus bar electrode 87 on the left side of the figure becomes substantially constant even if the position in the Y direction changes, as indicated by A in (B). . On the other hand, when the bus bar electrode 87 side is disconnected (B disconnection in (A)), the magnitude of the current flowing through the bus bar electrode 87 on the left side of the figure is as shown in B of (B) in the lower part near the disconnection point. It is small at a certain position in the Y direction and increases as it goes upward. Further, when the back electrode side terminal 81a side is disconnected (C disconnection in (A)), the magnitude of the current flowing through the bus bar electrode 87 on the left side of the figure is far from the disconnection location as indicated by C in (B). It is large at the position in the Y direction, which is the lower part, and becomes larger as it goes upward. These are presumed to be because the current at the position near the disconnection point hardly flows, and the current flowing through the grid electrode 86 and the like increases as the distance from the disconnection position increases.

  (C) shows the distribution in the Y direction of the magnitude of the current flowing through the right bus bar electrode 87 under the conditions of A, B, and C described above. In this case, contrary to the case of (B), the magnitude of the current in the Y direction position near the disconnection location of the left bus bar electrode 87 is large, and the magnitude of the current is smaller in the Y direction position far from the disconnection location. Become. This is presumed to be because the current that cannot flow through the left bus bar electrode 87 flows into the right bus bar electrode 87. As described above, when the bus bar electrode 87 side and the back electrode side terminal 81a side are disconnected, the magnitude of the current flowing through the left and right bus bar electrodes 87 and 87 is extremely large compared to the case where the bus bar electrode 87 and 87 are not disconnected. You can see that it changes. In the above description, the change in the magnitude of the current (the absolute value of the current) has been described. However, since the direction of the current flowing in the bus bar electrode 87 is almost the Y direction, the magnitude of the current in the Y direction is used. Gives the same result.

  (D) shows the distribution in the X direction of the magnitude of the current flowing between the left and right bus bar electrodes 87, 87 under the conditions of A, B, C described above. The current distribution in this case is the average value of the current distribution in the X direction over the entire longitudinal direction of the left and right bus bar electrodes 87, 87 or the current distribution in the X direction at the intermediate position of the bus bar electrodes 87, 87 in the longitudinal direction. . This current includes a surface current flowing on the surface of the solar cell SC in addition to the current flowing in the X direction through the grid electrode 86. Under normal conditions, almost no current flows between the bus bar electrodes 87 and 87. On the other hand, in the case of B disconnection, a current in the negative direction (that is, the left direction) flows. Further, in the case of C disconnection, a current in the positive direction (that is, right direction) flows. These are presumed to be because the current that cannot flow due to the disconnection flows between the bus bar electrodes 87 and 87. As described above, due to the disconnection, the magnitude of the current flowing between the bus bar electrodes 87 and 87 also greatly changes compared to the normal case. Further, since the direction of the current flowing between the bus bar electrodes 87 and 87 tends to be in the X direction, the same result can be obtained even if the magnitude of the current in the X direction is used.

  FIG. 10B shows the experimental results of the current magnitude distribution when the contact resistance r of the left bus bar electrode 87 of the solar battery cell SC is large. (A) shows an equivalent circuit in which a resistor is connected between the left and right bus bar electrodes 87 with a focus on one solar cell SC. In this case, the contact resistance r is realized by connecting 50 cm and 150 cm electric wires between the left and right bus bar electrodes 87, 87. The distance between the left and right bus bar electrodes 87, 87 is, for example, 5 cm. Also in this case, the current direction is positive in the upward direction and right direction in the figure. Due to such a contact resistance r, the magnitude of the current flowing through the bus bar electrode 87 on the left side of the figure changes as follows at the position in the Y direction. First, when normal (when the left and right bus bar electrodes 87, 87 are normally connected), the distribution of the magnitude of the current flowing through the bus bar electrode 87 on the left side of the figure is as shown in A of FIG. Even if the position in the Y direction changed, it became almost constant. On the other hand, when a 50 cm wire is connected between the left and right bus bar electrodes 87, 87, the magnitude of the current flowing through the left bus bar electrode 87 is large as shown in B of FIG. It is small at the position in the Y direction, which is the lower part, and becomes larger as it goes upward. When a 150 cm wire is connected between the left and right bus bar electrodes 87, 87, the magnitude of the current flowing through the left bus bar electrode 87 is large as shown in C of (B). At the lower position in the Y direction, it becomes even smaller. These are presumed to be because the current flowing through the grid electrode 86 and the like increases as the contact resistance r increases and the current at the position where it is difficult for the current to flow decreases, and the distance from the position where the current does not flow easily increases. This change in current is smaller than that in the case of the disconnection in FIG. 10A.

  (C) shows the distribution in the Y direction of the magnitude of the current flowing through the right bus bar electrode 87 under the conditions of A, B, and C described above. Also in this case, contrary to the case of (B), the magnitude of the current in the Y direction position where the contact resistance r of the left bus bar electrode 87 is large is large, and the magnitude of the current is larger in the Y direction position farther from the disconnection point. Becomes smaller. Also in this case, it is presumed that the current that cannot flow through the left bus bar electrode 87 flows into the right bus bar electrode 87. Thus, even when the contact resistance on the bus bar electrode 87 side is increased, the change is smaller than in the case of the disconnection, but the magnitude of the current flowing in the left and right bus bar electrodes 87 and 87 is determined by the contact resistance. It turns out that it changes very largely compared with the normal case. The same phenomenon also appears when the contact resistance on the back electrode 81 side increases. Also in this case, in the above description, the change in the magnitude of the current (the absolute value of the current) has been described. However, since the direction of the current flowing in the bus bar electrode 87 is almost the Y direction, the magnitude of the current in the Y direction is also described. The same result can be obtained using

  (D) shows the distribution in the X direction of the magnitude of the current flowing between the left and right bus bar electrodes 87, 87 under the conditions of A, B, C described above. The current distribution in this case is also the average value of the current distribution in the X direction over the entire longitudinal direction of the left and right bus bar electrodes 87, 87 or the current distribution in the X direction at the intermediate position of the bus bar electrodes 87, 87 in the longitudinal direction. . This current also includes a surface current flowing on the surface of the solar cell SC in addition to the current flowing in the X direction through the grid electrode 86. Under normal conditions, almost no current flows between the bus bar electrodes 87 and 87. On the other hand, when a 50 cm wire is connected between the left and right bus bar electrodes 87, 87, a current in the negative direction (that is, the left direction) flows. Further, when a 150 cm wire is connected between the left and right bus bar electrodes 87, 87, a current in the negative direction (that is, the left direction) having a larger absolute value than that in the case B is flowing. This is presumed to be because the current that cannot flow due to the contact resistance r flows between the bus bar electrodes 87 and 87. As described above, when the contact resistance of the electrode is increased, the change is smaller than that in the case of the disconnection, but the magnitude of the current flowing between the bus bar electrodes 87 and 87 is also greatly changed as compared with the normal case. Further, since the direction of the current flowing between the bus bar electrodes 87 tends to be in the X direction, the same result can be obtained even when the magnitude of the current in the X direction is used.

  FIG. 10C shows an experimental result of the distribution of current magnitude when a contact failure occurs between the bus bar electrode 87 and the grid electrode 86 of the solar battery cell SC. (A) shows an equivalent circuit in a state where the left bus bar electrode 87 is in poor contact with the grid electrode 86 at the upper position in the figure (indicated by the mark x in the figure), focusing on one solar cell SC. In this case as well, the current direction is positive in the upward direction and right direction in the figure. In this state, the magnitude of the current flowing through the bus bar electrode 87 on the left side of the figure changes as follows at the position in the Y direction. First, when there is no contact failure between the bus bar electrode 87 and the grid electrode 86, the distribution of the magnitude of the current flowing through the bus bar electrode 87 on the left side of the figure is slightly as shown in A of (B). Although it changed, it became almost constant even if the position in the Y direction changed. On the other hand, when a contact failure occurs between the bus bar electrode 87 and the grid electrode 86, the magnitude of the current flowing through the bus bar electrode 87 on the left side of the figure is as shown in FIG. It is large at the position in the Y direction and becomes smaller as it goes upward, which is the position of poor contact. This is presumably because the current flowing through the bus bar electrode 87 decreases at the contact failure position.

  (C) shows the distribution in the Y direction of the magnitude of the current flowing through the right bus bar electrode 87 under the conditions A and B described above. In this case, contrary to the case of (B), the magnitude of the current in the Y direction position, which is the upper part near the contact failure of the left bus bar electrode 87, is large, and the current in the Y direction position farther from the contact failure point is larger. The size becomes smaller. This is presumed to be because the current that cannot flow through the left bus bar electrode 87 flows into the right bus bar electrode 87. Thus, even when a contact failure occurs between the bus bar electrode 87 and the grid electrode 86, the magnitude of the current flowing through the left and right bus bar electrodes 87, 87 is larger than that when no contact failure occurs. It turns out that it changes very greatly. In the above description, the change in the magnitude of the current (the absolute value of the current) has been described. Also in this case, since the direction of the current flowing in the bus bar electrode 87 is substantially the Y direction, the magnitude of the current in the Y direction. The same result can be obtained using

  Further, (D) shows the distribution in the X direction of the magnitude of the current flowing between the left and right bus bar electrodes 87, 87 under the conditions of A and B described above. The current distribution in this case is also the average value of the current distribution in the X direction over the entire longitudinal direction of the left and right bus bar electrodes 87, 87 or the current distribution in the X direction at the intermediate position of the bus bar electrodes 87, 87 in the longitudinal direction. . Also in this case, this current includes a surface current flowing on the surface of the solar battery cell SC in addition to a current flowing in the grid electrode 86 in the X direction. Under normal conditions, almost no current flows between the bus bar electrodes 87 and 87. On the other hand, when a contact failure occurs between the bus bar electrode 87 and the grid electrode 86, a current in the positive direction (that is, the right direction) flows. This is presumed to be because the current that could not flow due to the poor contact location flows between the bus bar electrodes 87 and 87. As described above, even when a contact failure occurs between the bus bar electrode 87 and the grid electrode 86, the magnitude of the current flowing between the bus bar electrodes 87 and 87 also changes greatly as compared with the normal case. Also in this case, since the direction of the current flowing between the bus bar electrodes 87 and 87 tends to be in the X direction, the same result can be obtained even if the magnitude of the current in the X direction is used.

  Next, execution of the evaluation program will be described. The execution of this evaluation program is started in step S100 of FIG. 6A, and the controller 70 initializes the variables n and m to “1” and initializes the variable CH to “0” in step S102. Variables n and m are variables for designating detection positions in the X and Y axis directions, respectively. The values nmax and mmax represent the number of detection positions in the X and Y axis directions as described above. As will be described in detail later, the variable CH represents that the bus bar electrode 87 is extended in the Y-axis direction by “0”, and that the bus bar electrode 87 is extended in the X-axis direction by “1”. To express. After the processing in step S102, the controller 70 in step S104, the sampling data groups Sx1 (n, m), Sx2 (n, m), Sy1 (n, n) for each predetermined number K specified by the variables n and m. m), Sy2 (n, m) The average values Sx1, Sx2, Sy1, and Sy2 of the magnitude of the magnetic field are calculated. Specifically, for each sampling data group Sx1 (n, m), Sx2 (n, m), Sy1 (n, m), Sy2 (n, m), K sampling data is added to obtain a value K. Divide by.

Next, in step S106, the controller 70 executes the operations of the following formulas 1 and 2 using the calculated average values Sx1 and Sx2, and thereby the local maximum value Hx of the X direction magnetic detection signal and the X direction magnetic detection signal. The phase shift amount θx with respect to the reference signal is calculated.
Hx = (Sx1 ² + Sx2 ² ) ^1/2 Formula 1
θx = tan ^-1 (Sx2 / Sx1) ... Formula 2
As a result, Hx · sin (2πft + θx) is detected as the X-direction magnetic detection signal. Note that f is equal to the frequency of the light emission signal and the reference signal output from the light emission signal supply circuit 65.

Next, in step S108, the controller 70 performs the operations of the following formulas 3 and 4 using the calculated average values Sy1 and Sy2, and thereby the maximum value Hy of the Y-direction magnetic detection signal and the Y-direction magnetic detection signal. The phase shift amount θy with respect to the reference signal is calculated.
Hy = (Sy1 ² + Sy2 ² ) ^1/2 Formula 3
θy = tan ^-1 (Sy2 / Sy1) ... Equation 4
As a result, Hy · sin (2πft + θy) is detected as the Y-direction magnetic detection signal.

Next, in step S110, the controller 70 performs the calculation of the following formulas 5 and 6 using the calculated Hx, θx, Hy, θy, and the timing at which the energization current becomes maximum (the X-direction magnetic detection signal). The magnetic field strength Hxy and the magnetic field direction θxy at the inspection position at Hx · sin (2πft + θx) and 2πft in the Y-direction magnetic detection signal Hy · sin (2πft + θy) at π / 2 are calculated. In this case, the reason why the timing at which the energization current becomes maximum is adopted is that the phase shift amounts θx and θy are small, and the magnetic field strength Hxy at the inspection position becomes a value near the maximum value near the timing at which the energization current becomes maximum. Because. When the phase shift amounts θx and θy are not small and the magnetic field strength Hxy at the inspection position is not near the maximum value near the timing when the energization current is maximum, the magnetic field strength Hxy is near the maximum value. Such a timing angle may be used instead of π / 2.
Hxy = [{Hx · sin (π / 2 + θx)} ² + {Hy · sin (π / 2 + θy)} ² ] ^1/2
θxy = tan ⁻¹ {Hy · sin (π / 2 + θy)} / {Hx · sin (π / 2 + θx)} Equation 6

Next, in step S112, the controller 70 determines that the current flowing through the solar cell panel SP is proportional to the magnetic field strength Hxy and the direction differs from the magnetic field direction θxy by −π / 2. , Θxy are used to calculate the magnitude Ixy and the direction θixy of the current flowing at the inspection position in the electrolyte of the fuel cell FC at the timing when the energization current becomes the maximum. However, the value K is a proportionality constant.
Ixy = K · Hxy Equation 7
θixy = θxy−π / 2 Equation 8
In step S112, the calculated current magnitude Ixy and direction θixy are obtained by using the variables n and m representing the inspection position of the fuel cell FC and the current magnitude data Ixy (n, m) and direction. It is stored in the RAM or storage device as data θixy (n, m).

Next, in step S114, the controller 70 executes the calculations of the following formulas 9 and 10 using the calculated Ixy and θixy, and thereby the magnitude of the current flowing in the X direction and the Y direction at the inspection position of the solar cell panel SP. Ix and Iy are calculated.
Ix = Ixy · cosθixy (Equation 9)
Iy = Ixy · sinθixy (Formula 10)
In step S114, the calculated current magnitudes Ix and Iy are also obtained from the current magnitude data Ix (n, m) and Iy using the variables n and m representing the inspection position of the solar cell panel SP. (n, m) is stored in the RAM or storage device.

  In step S116, the controller 70 determines whether the variable n has reached a value nmax representing the number of detected positions in the X-axis direction. If the variable n has not reached the value nmax, the controller 70 determines “No” in step S116, adds “1” to the variable n in step S118, and returns to step S104. Then, after executing the processing of steps S104 to S114 described above, the controller 70 determines again whether or not the variable n has reached the value nmax in step S116. As long as the variable n does not reach the value nmax, the processes of steps S104 to S118 are repeatedly executed.

  When the variable n reaches the value nmax during the repeated processing of steps S104 to S118, the controller 70 determines “Yes” in step S116, and the variable m is detected in the Y-axis direction in step S120. It is determined whether or not the value mmax representing the number has been reached. If the variable m does not reach the value mmax, the controller 70 determines “No” in step S120, adds “1” to the variable m in step S112, and sets the variable n to “1” in step S124. Initialization is performed, and the process returns to step S104. Then, after repeatedly executing the processes of steps S104 to S118 described above until the variable n reaches the predetermined value nmax, the controller 70 determines again whether or not the variable m has reached the value mmax in step S120. As long as the variable m does not reach the value mmax, the processes in steps S104 to S124 are repeated. When the variable m reaches the value mmax, the controller 70 determines “Yes” in step S120, and proceeds to step S130 in FIG. 6B.

  At this time, the current magnitude data Ixy (n, m), the current direction data θixy (n, m), and the current magnitude data Ix (n, m) in the X direction for each inspection position of the solar cell panel SP. ) And Y-direction current magnitude data Iy (n, m) (n = 1 to nmax, m = 1 to mmax) are stored in the RAM or the storage device.

  Next, the processing of steps S130 to S134 for extracting the current magnitude data Ixy (n, m) at the bus bar electrode 87 position is executed. First, in step S130, the controller 70 extracts the maximum current magnitude as the maximum current Imax from all the calculated current magnitude data Ixy (n, m). Next, in step S132, the controller 70 determines the current magnitude closest to the maximum current Imax and having a maximum frequency distribution in the distribution of all current magnitude data Ixy (n, m). Calculate as the value Ic. FIG. 11 shows the distribution of the current magnitude data Ixy (n), the maximum current Imax and the current value Ic. After the processing in step S132, in step S134, the controller 70 determines the magnitude of the current greater than or equal to the value {Ic-2 · (Imax−Ic)} from all the current magnitude data Ixy (n). Data Ixy (n) is extracted. The processing in these steps S130 to S134 is based on the fact that the current magnitude data Ixy (n, m) at the position of the bus bar electrode 87 is significantly larger than the other portions. Thereby, at least large current magnitude data Ixy (n, m) including current magnitude data at the position of the bus bar electrode 87 is extracted.

  Next, the processing of steps S140 to S162 for detecting whether the bus bar electrode 87 is extended in the Y-axis direction or the X-axis direction depending on how the solar cell panel SP is placed on the stage 40. Execute. First, the controller 70 initializes the variable n to “1” in step S140, and in step S142, the current magnitude data Ixy (n, m) extracted by the process in step S134 is set according to the variable n. The number of size data Ixy (n, m) that are specified and the variable m is continuous is calculated and set as a value Nn. In step S144, the controller 70 determines whether the value Nn is a predetermined number or more. In this determination process, if the bus bar electrode 87 is at the position in the X-axis direction specified by the variable n and extends in the Y-axis direction, the value Nn is the length of one solar cell SC in the Y-axis direction. This is based on the fact that the size is divided by the detection interval ΔY in the Y-axis direction (see FIG. 9). Therefore, as described above, the predetermined number is slightly smaller than the value obtained by dividing the length in the Y-axis direction of one solar cell SC input by the operator by the detection interval ΔY. In this case, if the value Nn is not equal to or greater than the predetermined number, the controller 70 determines “No” in step S144 and proceeds to step S146.

  In step S146, the controller 70 determines whether or not a value n · ΔX obtained by multiplying the variable n by the detection interval ΔX (see FIG. 9) in the X-axis direction is equal to or greater than a predetermined distance. This processing is performed in the above-described steps S142 and S144 by a length corresponding to the width in the X-axis direction of one solar cell SC due to a change in the X-axis direction of the detection position due to an increase in the variable n described later. It is determined whether the processing has been executed. Therefore, the predetermined distance is substantially equal to the length in the X-axis direction of one solar cell SC input by the operator. If the value n · ΔX is not equal to or greater than the predetermined distance, the controller 70 determines “No” in step S146, adds “1” to the variable n in step S148, and returns to step S142. When the value Nn calculated by the process of step S142 becomes equal to or greater than a predetermined number during the circulation process including these steps S142 to S146, the controller 70 determines “Yes” in step S144, that is, the bus bar electrode 87 is connected to the Y axis. It determines with extending in the direction, and proceeds to step S170 in FIG. 6C. On the other hand, if it is not detected that the value Nn exceeds the predetermined number and the value n · ΔX exceeds the predetermined distance, the controller 70 determines “Yes” in step S146, that is, the bus bar electrode 87 extends in the Y-axis direction. It determines with having not been performed, and performs the process of step S150-S156.

  The processes in steps S150 to S156 are processes for detecting whether the bus bar electrode 87 is extended in the X-axis direction. First, the controller 70 initially sets a variable m to “1” in step S150, and in step S152, in the current magnitude data Ixy (n, m) extracted by the process of step S134, according to the variable m. The number of size data Ixy (n, m) that are specified and the variable n is continuous is calculated and set as a value Nm. In step S154, the controller 70 determines whether the value Nm is a predetermined number or more. In this determination process, if the bus bar electrode 87 is at the position in the Y-axis direction specified by the variable m and is extended in the X-axis direction, the value Nm is the length of one solar cell SC in the X-axis direction. This is based on the fact that the size is divided by the detection interval ΔX in the X-axis direction (see FIG. 9). Therefore, the predetermined number is slightly smaller than a value obtained by dividing the length in the X-axis direction of one solar cell SC input by the operator by the detection interval ΔX. In this case, if the value Nm is not equal to or greater than the predetermined number, the controller 70 determines “No” in step S154 and proceeds to step S156.

  In step S156, the controller 70 determines whether or not a value m · ΔY obtained by multiplying the variable m by the detection interval ΔY (see FIG. 9) in the Y-axis direction is equal to or greater than a predetermined distance. This processing is performed in the steps S152 and S154 by the length corresponding to the width in the Y-axis direction of one solar cell SC due to the change in the detection position in the Y-axis direction due to the increase in the variable m described later. It is determined whether the processing has been executed. Therefore, the predetermined distance is substantially equal to the length in the Y-axis direction of one solar cell SC input by the operator. If the value m · ΔY is not equal to or greater than the predetermined distance, the controller 70 determines “No” in step S156, adds “1” to the variable m in step S158, and returns to step S152. When the value Nm calculated by the process of step S152 becomes equal to or larger than a predetermined number during the circulation process including these steps S152 to S156, the controller 70 determines “Yes” in step S154, that is, the bus bar electrode 87 is the X axis. It determines with extending in the direction, and proceeds to step S170 of FIG. 6C after the processing of steps S160 and S162.

  In step S160, the controller 70 rearranges the current magnitude data Ixy (n, m) extracted by the process in step S134 into the current magnitude data Ixy (m, n). This is a common process in the case where the bus bar electrode 87 is extended in the X-axis direction and the case where the bus bar electrode 87 is extended in the Y-axis direction. The X coordinate value of the size data Ixy (n, m) is changed to the Y coordinate value, and the Y coordinate value is changed to the X coordinate value. In step S162, the controller 70 indicates that the variable CH is rearranged from the current magnitude data Ixy (n, m) to the current magnitude data Ixy (m, n), and the bus bar electrode 87 is It is changed to “1” indicating that it extends in the X-axis direction.

  On the other hand, if it is not detected that the value Nm exceeds the predetermined number and the value m · ΔY exceeds the predetermined distance, the controller 70 determines “Yes” in step S156, that is, the bus bar electrode 87 extends in the Y-axis direction. If it is not determined, the process proceeds to step S310 in FIG. 6H. The determination of “Yes” in step S156 means that neither the extension of the bus bar electrode 87 in the X-axis direction nor the extension in the Y-axis direction is detected.

  Next, electrode position coordinates Bxy (n, m) (that is, a detection position group by the magnetic sensor 10) indicating the position of the bus bar electrode 87 is detected, and the order of the X direction and the Y direction of the bus bar electrodes 87 arranged in a matrix form. A process of steps S170 to S214 in FIG. 6C and FIG. 6D in which the X-direction electrode number gx and the Y-direction electrode number gy (see FIG. 7) for specifying the position are assigned to the detected electrode position coordinates Bxy (n, m) will be described. . The values n and m are variables indicating the detection positions by the magnetic sensor 10 in the X-axis direction and the Y-axis direction, respectively. First, in step S170 of FIG. 6C, the controller 70 initializes the variable n to “1”, and initializes the X-direction electrode number gx and the Y-direction electrode number gy to “1”, respectively.

  Next, in step S172, the controller 70 includes current magnitude data Ixy (n, m) included in the current magnitude data Ixy (n, m) extracted in step S134 and specified by the variable n. ) As the value Nnm. In step S174, the controller 70 determines whether this value Nnm is a predetermined number or more. In the processing of these steps S172 and S174, if the position in the X direction specified by the variable n corresponds to the position of the bus bar electrode 87, the current magnitude data Ixy (n, m) is Since it should be large, the value Nnm should also be large. The predetermined number is a value determined by the total length of the bus bar electrodes 87 in the Y direction and the movement distance unit ΔY in the Y direction. It is. The reason why the value is set lower is that there is a possibility that there is a bus bar electrode 87 with a small current due to an abnormality, as will be described later. If the position in the X direction specified by the variable n does not correspond to the position of the bus bar electrode 87, the value Nnm is small, so the controller 70 determines “No” in step S174, and the variable n in step S176. Determines whether or not the value nmax representing the number of detected positions in the X-axis direction has been reached. If the variable n has not reached the value nmax, the controller 70 determines “No” in step S176, adds “1” to the variable n in step S178, and performs the processing in steps S172 and S174. Execute.

  When the X direction position specified by the variable n corresponds to the position of the bus bar electrode 87 and the value Nnm is larger than the predetermined number, the controller 70 determines “Yes” in step S174, and in step S180. The variable m indicating the detection position of the magnetic sensor 10 in the Y-axis direction is initially set to “1”, and the number of detection positions in the Y-axis direction of the bus bar electrode 87 (the length of the bus bar electrode 87 is the moving distance in the Y-axis direction). The variable p for counting (the number divided by the unit ΔY) is initialized to “0”, and the determination process of steps S182 to S186 is executed.

  Before describing the determination processing in steps S182 to S186, the distribution of current magnitude data Ixy (n, m) in the Y direction at the X position corresponding to the bus bar electrode 87 will be described. As shown in FIG. 12, the plurality of bus bar electrodes 87 are arranged along the Y direction. The plurality of bus bar electrodes 87 are connected to the back electrode 81 by connection lines 88 as shown in FIGS. 12 and 13A. In this case, although the magnitude data Ixy (n, m) of the current flowing through the bus bar electrode 87 is large, the current flowing through the connection line 88 is not a current flowing through the XY plane but a component flowing in the Z direction (downward). Small to contain. Therefore, the current flowing in the Y direction along the plurality of bus bar electrodes 87 is large at the position corresponding to the bus bar electrode 87 and small at the position corresponding to the connection line 88, as shown in FIG. And the connection line 88 change continuously and rapidly.

  Returning to the description of FIG. 6C, in step S182, the variable m is included in the current magnitude data group Ixy (n, m) (where the variable n is a specific value) extracted by the process of step S134. It is determined whether or not there is current magnitude data Ixy (n, m) specified by. In this case, if the position in the Y direction specified by the variable m is a position corresponding to the bus bar electrode 87, the current magnitude data Ixy (n, m) at that position is large as shown in FIG. Therefore, in the determination in step S182, it is determined that “Yes”, that is, exists. If the position in the Y direction specified by the variable m is a position corresponding to the connection line 88 and away from the bus bar electrode 87, the current magnitude data Ixy (n, m) at that position is small. In the determination in step S182, it is determined “No”, that is, it does not exist.

  In step S184, current magnitude data Ixy (n, m) designated by variables n and m, current magnitude data Ixy (n, m-1) designated by variables n and m-1, and It is determined whether or not the value {Ixy (n, m) −Ixy (n, m−1)} / Ixy (n, m−1) calculated by using is less than or equal to a predetermined negative value −Io. . This is because the position specified by the variable m exceeds the bus bar electrode 87 due to the increase of the variable m and enters the area of the connection line 88. However, since the position is close to the bus bar electrode 87, “Yes”, that is, Even when it is determined that it exists, it is determined that the position does not correspond to the bus bar electrode 87. That is, if the position in the Y direction specified by the variable m is immediately after entering the connection line 88 region, the current magnitude data Ixy (n, m) should decrease rapidly. The current magnitude data Ixy (n, m) at the designated Y-direction position is the current magnitude data Ixy (n, m) at the Y-direction position immediately before the Y-direction position designated by the variable m-1. m) should be somewhat smaller. Therefore, in this case, the calculated value {Ixy (n, m) −Ixy (n, m−1)} / Ixy (n, m−1) should be a negative value having a large absolute value to some extent. It is. Therefore, even if the position specified by the variable m exceeds the bus bar electrode 87 and enters the region of the connection line 88, if it is determined as “Yes”, that is, exists by the processing of step S182, in step S184 “Yes” is determined, otherwise “No” is determined.

  In step S186, the current magnitude data Ixy (n, m) specified by the variables n and m and the current magnitude data Ixy (n, m-1) specified by the variables n and m + 1 are used. It is determined whether the value {Ixy (n, m) −Ixy (n, m + 1)} / Ixy (n, m + 1) calculated in this way is equal to or less than a predetermined negative value −Io. This is because the position specified by the variable m is in the area of the connection line 88, but has approached the bus bar electrode 87 due to the increase in the variable, so that even when it is determined as “Yes”, that is, exists by the processing of step S182. It is determined that the position does not correspond to the bus bar electrode 87. That is, if the position in the Y direction specified by the variable m is immediately before entering the bus bar electrode 87 region, the current magnitude data Ixy (n, m) should increase rapidly. The current magnitude data Ixy (n, m) at the Y-direction position is obtained from the current magnitude data Ixy (n, m) at the Y-position after one of the Y-direction positions specified by the variable m + 1. Should be small to some extent. Therefore, in this case, the calculated value {Ixy (n, m) −Ixy (n, m + 1)} / Ixy (n, m + 1) should be a negative value having a large absolute value to some extent. Therefore, even if the position specified by the variable m is in the region of the connection line 88 approaching the bus bar electrode 87, if it is determined as “Yes”, that is, exists by the processing in step S182, in this step S186. “Yes” is determined, otherwise “No” is determined.

  Therefore, if the position in the Y direction specified by the variable m is a position corresponding to the bus bar electrode 87, the controller 70 determines “Yes” in step S182, and “No” in steps S184 and S186, respectively. In step S188, “1” is added to the variable p. In step S190, “1” is added to the variable m. Then, the process returns to step S182. Even if the detection position is moved in the Y direction due to an increase in the variable m, as long as the detection position is a position corresponding to the bus bar electrode 87, the cyclic processing of steps S182 to S190 is repeatedly performed, so that the variable p is the variable m. Increase with increasing. If the detection position exceeds the bus bar electrode 87 and enters the region of the connection line 88 during the circulation processing of steps S182 to S190, the controller 70 returns “No” in step S182 or “Yes” in steps S184 and S186. Determination is made, and the process proceeds to step S192 in FIG. 6D.

  In step S192, it is determined whether the variable p is greater than or equal to a predetermined number. In this case, the predetermined number is slightly smaller than the value obtained by dividing the length of the bus bar electrode 87 by the movement distance unit ΔY. In the present embodiment, the length and movement of the input solar cell SC in the Y direction. This value is predetermined by the distance unit ΔY. If the current magnitude Ixy (n, m) corresponding to the position of the bus bar electrode 87 is accurately detected, the variable p is equal to or greater than a predetermined number, and therefore the controller 70 determines “Yes” in step S192. In step S194, the X-direction electrode number is set to any one of the electrode position coordinates Bxy (n-1, mp) to Bxy (n-1, m-1) representing the XY coordinate position of the bus bar electrode 87. It is determined whether or not gx and Y-direction electrode number gy are assigned. In this determination process, the electrode position coordinates Bxy (n, m) representing the position of the bus bar electrode 87 detected this time are defined, and the X-direction electrode number gx and the Y-direction electrode number gy are added to the electrode position coordinates Bxy (n, m). Are assigned to the electrode position coordinates Bxy (n−1, m) corresponding to the position of the previously detected bus bar electrode 87, the position of which is designated by the variable n−1, and the X direction electrode number gx and the Y direction electrode number. It is determined whether gy has already been allocated. If the electrode position coordinates Bxy (n−1, m−p) to Bxy (n−1, m−1) representing the position of the bus bar electrode 87 detected last time are still the X direction electrode number gx and the Y direction electrode number gy. If not assigned (that is, if the electrode position coordinates Bxy (n−1, m−p) to Bxy (n−1, m−1) have not been defined yet), the controller 70 returns “No” in step S194. In step S196, the electrode position coordinates Bxy (n, mp) to Bxy (n, m-1) are defined, and the X direction electrode number gx and the Y direction electrode number gy are assigned, and step S206 is performed. Proceed to In this case, by using the variable p, the electrode position coordinates Bxy (n, mp) to Bxy (n, m-1) corresponding to the position corresponding to the length of the bus bar electrode 87 are defined. The X-direction electrode number gx and the Y-direction electrode number gy are assigned to the electrode position coordinates Bxy (n, mp) to Bxy (n, m-1).

  On the other hand, if the X-direction electrode number gx and the Y-direction electrode number gy are already assigned to the previously detected electrode position coordinates Bxy (n−1, m−p) to Bxy (n−1, m−1), the controller 70 determines “Yes” in step S194, and proceeds to steps S198 and S200. In step S198, current magnitude data Ixy (n-1, m-) at positions corresponding to the previously detected electrode position coordinates Bxy (n-1, mp) to Bxy (n-1, m-1). An average value Iaveb of p) to Ixy (n-1, m-1) is calculated. In step S200, current magnitude data Ixy (n, mp) to Ixy at positions corresponding to the electrode position coordinates Bxy (n, mp) to Bxy (n, m-1) detected this time. An average value Iavea of (n, m-1) is calculated. In step S202, the controller 70 determines whether or not the current average value Iavea is equal to or greater than the previous average value Iaveb. If the current average value Iavea is equal to or greater than the previous average value Iaveb, the controller 70 determines “Yes” in step S202 and determines the previously detected electrode position coordinates Bxy (n−1, m−p) to Bxy. The X-direction electrode number gx and the Y-direction electrode number gy assigned to (n−1, m−1) are used as electrode position coordinates Bxy (n, mp) to Bxy (n, m−1) detected this time. And proceed to step S206. On the other hand, if the current average value Iavea is not equal to or greater than the previous average value Iaveb, the controller 70 determines “No” in step S202 and proceeds to step S206 without changing the allocation. Through the processing of these steps S194 to S204, a set of current magnitude data Ixy (n, mp) to Ixy (n, m-1) having the largest average current is applied to one bus bar electrode 87. The X-direction electrode number gx and the Y-direction electrode number gy are assigned only to the electrode position coordinates Bxy (n, mp) to Bxy (n, m-1) corresponding to. In step S206, the controller 70 adds “1” to the Y-direction electrode number gy and proceeds to step S208. This means that the next bus bar electrode 87 is detected along the Y direction in FIG.

  In the determination process of step S192, if “No”, that is, the variable p is less than a predetermined number, the controller 70 determines “No” in step S192 and executes the processes of steps S194 to S206. Instead, the process proceeds to step S208. In this case, the X-direction electrode number gx and the Y-direction electrode number gy are not assigned to the electrode position coordinates Bxy (n, mp) to Bxy (n, m-1).

  In step S208, it is determined whether the variable m has reached the value mmax (that is, the value of the variable m related to the sampling data group at the detection position immediately before the end value Ymax). If the variable m has not reached the value mmax, the controller 70 determines “No” in step S208, initializes the variable p to “0” in step S210, and proceeds to step S190 in FIG. 6C. . The controller 70 adds “1” to the variable m in step S190, and executes the determination processing in steps S182 to S184 again. The processing in steps S180 to S184 is processing for determining that the detection position in the Y direction corresponds to the connection line 88 between the bus bar electrodes 87 as described above. Then, in a state where the detection position is at a position corresponding to the connection line 88, the controller 70 determines “No” in step S182 or “Yes” in steps S184 and S186, and proceeds to step S192 in FIG. 6D. . In this case, since the variable p is maintained at “0” by the process of step S210, the controller 70 continues to determine “No” in step S192, and steps S192, S208, S210 of FIG. 6D and FIG. The circulation process of steps S190 and S182 to S186 is repeatedly executed.

  During the circulation process, when the detection position reaches the position corresponding to the bus bar electrode 87 due to the increase of the variable m in step S190, the controller 70 determines “Yes” in step S182, step S184, as described above. In S186, each is determined as “No”, and the circulation process of steps S182 to S190 is repeatedly executed. When the detection position enters the region of the connection line 88, as described above, the controller 70 determines “No” in step S182 or “Yes” in steps S184 and S186, and step S192 in FIG. 6D. The process of S206 is executed. Through the processing of these steps S192 to S206, electrode position coordinates Bxy (n, mp) to Bxy (n, m-1) corresponding to the next bus bar electrode 87 in the Y direction are defined, and the next X direction electrode A number gx and a Y-direction electrode number gy are assigned. When the variable p is less than the predetermined number, the assignment of the X-direction electrode number gx and the Y-direction electrode number gy is not performed based on the determination of “No” in Step S192.

  After the processes in steps S192 to S206, the controller 70 executes the processes in steps S208 and S210, and again proceeds to step S190 in FIG. 6C. Thus, as the variable m increases, electrode position coordinates Bxy (n, mp) to Bxy (n, m-1) representing the position of the bus bar electrode 87 in the Y direction shown in FIG. The direction electrode number gx and the Y direction electrode number gy are assigned. When the variable m reaches the value mmax, the controller 70 determines “Yes” in step S208, adds “1” to the X direction electrode number gx in step S212, and sets the Y direction electrode number gy to “ 1 ”, and the process proceeds to step S178 in FIG. 6C. The controller 70 adds “1” to the variable n in step S178, and then proceeds to step S172. By the cyclic processing in steps S172 to S178 described above, the controller 70 determines the next row of bus bar electrodes 87 in the X direction shown in FIG. To detect. Then, a plurality of bus bar electrodes 87 in the Y direction in the next column in the X direction are detected by the processes in steps S182 to S210, and steps S170 to S190 in FIG. 6C and the processes in FIG. 6D after the processes in steps S212 and S214 are detected. By the processing of steps S192 to S210, the bus bar electrodes 87 are successively detected while moving in the X direction, and electrode position coordinates Bxy (n, mp) to Bxy (n, m-1) representing the positions of the bus bar electrodes 87 are detected. ) Are defined one after another, and an X-direction electrode number gx and a Y-direction electrode number gy are assigned. When the variable n reaches the value nmax (the value of the variable n related to the sampling data group at the detection position immediately before the end value Xmax), the controller 70 determines “Yes” in step S176 and performs step S220 in FIG. 6E. Proceed to

  Next, the electrode position coordinates Bxy (n, m) (that is, the detected position group by the magnetic sensor 10) indicating the position of the bus bar electrode 87 to be extracted by the processing of the steps S170 to S214 is due to an abnormality such as disconnection or contact failure. A portion that is not extracted because the current magnitude data is small is detected, and an X-direction electrode number gx and a Y-direction electrode number gy (see FIG. 7) are assigned to the electrode position coordinates Bxy (n, m) of the detected portion. Processing in steps S220 to S256 in FIGS. 6E and 6F will be described. First, the controller 70 initially sets the variables k and s to “1” in step S220 of FIG. 6E. The variable k is a variable for designating the bus bar electrode 87 in the X direction. The variable s is a variable for designating the bus bar electrode 87 in the Y direction.

  Next, in step S222, the controller 70 determines that the maximum value of the Y-direction electrode number gy assigned by the assignment process of the X-direction electrode number gx and the Y-direction electrode number gy is the input Y-direction solar cell. It is determined whether or not it is equal to the number of SCs. That is, it is determined whether or not the positions of all the bus bar electrodes 87 in the Y direction are detected in at least one of the assigned X direction electrode numbers gx. All the bus bar electrodes 87 in the Y direction are detected like the two rows of bus bar electrodes 87 along the X direction from the left side of FIG. 12, and the maximum value of the Y direction electrode number gy is the solar cell SC in the Y direction. If equal to the number, the controller 70 determines “Yes” in step S222 and proceeds to step S224. On the other hand, if the maximum value of the Y-direction electrode number gy is not equal to the number of solar cells SC in the Y direction, the controller 70 determines “No” in step S222 and proceeds to step S310 in FIG. 6H. This is because the position of all the bus bar electrodes 87 in the Y direction is not detected in the row of all the bus bar electrodes 87 in the X direction because there is a high possibility that an input error or some abnormality has occurred. .

  In step S224, whether or not the maximum value of the Y-direction electrode number gy specified by the X-direction electrode number gx (gx = k) equal to the variable k is equal to the number of the input Y-direction solar cells SC. Is determined. When the maximum value is equal to the number of solar cells SC in the Y direction (the left two rows of bus bar electrode 87 groups in FIG. 12), that is, when the detection position groups by all the Y direction magnetic sensors 10 are extracted. The controller 70 determines “Yes” in step S224, and in step S226, the variable k is the maximum value of the X-direction electrode number gx (that is, the number of solar cells SC in the X direction is one solar cell SC. It is determined whether it is equal to the value obtained by multiplying the number of bus bar electrodes 87. Then, on the condition that they are not equal, “1” is added to the variable k in step S228, and the determination processing in step S224 is executed again. Thus, if the detection position groups by all the magnetic sensors 10 in the Y direction have been extracted, the processing of steps S224 to S228 is performed while sequentially increasing the variable k for designating the position of the bus bar electrode 87 in the X direction. Execute.

  When it is determined in step S224 that “No”, that is, the detection position group by all the magnetic sensors 10 in the Y direction has not been extracted, the controller 70 determines in step S230 the X-direction electrode number gx equal to the variable k. Is calculated for each Y-direction electrode number gy for the median value Avem in the Y-direction of the electrode position coordinates Bxy (n, m). Next, in step S232, the controller 70 subtracts the absolute value | Avem (s + 1) −Avem (s) obtained by subtracting the Avem (s) specified by the variable s and the value ce from the Avem (s + 1) specified by the variable s + 1. ) −ce | is determined whether it is equal to or smaller than a predetermined small value Δp. In this case, when the variable CH is “0” and the bus bar electrode 87 is extended in the Y-axis direction, the value ce is obtained by dividing the length of the solar cell SC in the Y direction by the movement distance unit ΔY. It is the value. On the other hand, when the variable CH is “1” and the bus bar electrode 87 is extended in the X-axis direction, that is, the current magnitude data Ixy (n, m) is obtained as a result of the process of step S160 in FIG. 6B. When rearranged in the size data Ixy (m, n), the value ce is a value obtained by dividing the length of the solar cell SC in the X direction by the movement distance unit ΔX. Therefore, the value ce is equal to the number of detected positions in the extending direction of the bus bar electrode 87.

  If the bus bar electrode 87 is continuously detected in the Y direction, the absolute value | Avem (s + 1) −Avem (s) −ce | is almost “0”. Therefore, in this case, the controller 70 determines “Yes” in step S232, adds “1” to the variable s in step S234, and then determines the next center specified by the variable s + 1 in step S236. “Yes” is determined on condition that the value Avem (s + 1) exists, and the determination process in step S232 is executed again. On the other hand, when the fourth bus bar electrode 87 in the Y direction is not detected as in the third column in the X direction in FIG. 12, when the variable s is “3”, the absolute value | Avem (s + 1) − Avem (s) −ce | is approximately the value ce. In this case, the controller 70 determines “No” in step S232, and in step S238, the electrode position coordinates assigned to the X-direction electrode number gx equal to the variable k and the Y-direction electrode number gy equal to the variable s. An electrode position coordinate Bxy (n, m + ce) obtained by adding the value ce to the variable m of Bxy (n, m) is newly defined, and the X-direction electrode equal to the variable k is defined in the defined electrode position coordinate Bxy (n, m + ce). Assign the Y-direction electrode number gy equal to the number gx and the variable s + 1, and calculate the median value Avem (gy) of the variable m. Next, in step S240, the Y-direction electrode number gy of the electrode position coordinate Bxy (n, m) to which the X-direction electrode number gx equal to the variable k and the Y-direction electrode number gy equal to or greater than the variable s + 1 are assigned is set in the Y direction Change to electrode number gy + 1. As a result, the electrode position coordinate Bxy (n, m) corresponding to the fourth bus bar electrode 87 in the Y direction in the third column in the X direction in FIG. 12 is replenished, and its median value Avem is also calculated. The electrode number gy is also sequentially assigned to all electrode position coordinates Bxy (n, m) in the Y direction.

  Further, when the third and fourth bus bar electrodes 87 in the Y direction are not continuously detected as in the fourth column in the X direction in FIG. 12, the absolute value is obtained when the variable s is “2”. | Avem (s + 1) −Avem (s) −ce | is approximately the value 2 · ce. In this case, the electrode position coordinates Bxy (n, m) corresponding to the third bus bar electrode 87 in the fourth column in the X direction and the third bus bar electrode 87 are replenished by the processing in steps S238 and S240 described above. The median value Avem is also calculated, and the Y-direction electrode number gy is also sequentially assigned to all electrode position coordinates Bxy (n, m) in the Y direction. In this case, however, the absolute value | Avem (s + 1) −Avem (s) −ce | becomes substantially the value ce when the variable s becomes “3” even by this replenishment. Therefore, after the process of step S234, the controller 70 determines “Yes” in step S236, determines “No” in step S232, and executes the processes of steps S238 and S240 again. As a result, the electrode position coordinates Bxy (n, m) corresponding to the fourth bus bar electrode 87 in the fourth row in the X direction and the median value Avem are calculated, and the Y direction electrode number gy is also calculated. Are also sequentially assigned to all electrode position coordinates Bxy (n, m) in the Y direction. As a result, the number of electrode position coordinates Bxy (n, m) corresponding to the bus bar electrode 87 in the fourth row is also equal to the number of solar cells SC. Even if three or more electrode position coordinates Bxy (n, m) are missing, similarly, the missing electrode position coordinates Bxy (n, m) are replenished by the processing in steps S232 to S240.

  If the median value Avem (s + 1) specified by the variable s + 1 does not exist during the processing of steps S232 to S240, that is, the median value Avem (s + 1) of the next electrode position coordinate Bxy (n, m) in the Y direction is obtained. When it does not exist, the controller 70 determines “No” in step S236, and in step S242, the controller 70 determines the maximum value of the Y-direction electrode number gy specified by the X-direction electrode number gx equal to the variable k. Determine if there is. If it is the maximum value, the controller 70 determines “Yes” in step S242, and executes the processes after step S226 described above. When the variable k becomes equal to the maximum value of the X-direction electrode number gx by the processing of step S228, that is, when the replenishment processing of the electrode position coordinates Bxy (n, m) of the last column in the X direction is completed, the controller 70 In step S228, “Yes” is determined, and the process proceeds to step S260 in FIG. 6G.

  On the other hand, when the last bus bar electrode 87 in the Y direction is not detected as in the fifth and sixth columns in the X direction in FIG. 12, or in the seventh and eighth columns in the X direction in FIG. On the other hand, when the first bus bar electrode 87 in the Y direction has not been detected, the missing of the electrode position coordinates Bxy (n, m) cannot be replenished by the processing in steps S232, S238, and S240 described above. In this case, even when the median value Avem (s + 1) (that is, the next median value Avem) no longer exists, the variable s is not equal to the maximum value of the Y-direction electrode number gy, and the controller 70 performs step S242. It determines with "No" and progresses to step S244 of FIG. 6F.

  In step S244, the controller 70 converts the X coordinate value n of the electrode position coordinate Bxy (n, m) assigned the X direction electrode number gx equal to the variable k and the Y direction electrode number gy equal to the variable s to the X direction coordinate. A value Avem (s) + ce obtained by adding the predetermined value ce (the number of detected positions in the Y direction of the solar cells SC) to the median value Avem (s) designated by the variable s is set as nx, and the Y direction coordinate ny And Then, the maximum value is extracted from the current magnitude data Ixy (nx-a, ny-a) to Ixy (nx + a, ny + a) specified by the coordinates nx, ny and is set as the maximum current value Iemax. The value a is a predetermined value of about 5 to several tens. As a result, the maximum value of the current magnitude data Ixy (n, m) in the predetermined range at the position surrounding the central coordinate value of the electrode position coordinate Bxy (n, m) is set as the maximum current value Iemax. After the processing in step S244, the controller 70 determines in step S246 whether the maximum current value Iemax is greater than or equal to a set value. Note that this set value is a relatively small predetermined current value detected at the position of the bus bar electrode 87 even if the solar cell SC is abnormal if the solar cell SC exists.

  If the bus bar electrode 87 is present at the position and the maximum current value Iemax is greater than or equal to the set value, the controller 70 determines “Yes” in step S246 and proceeds to step S248. This is processing when the last bus bar electrode 87 in the Y direction is not detected as in the fifth or sixth row in the X direction in FIG. In step S248, the electrode position obtained by adding the predetermined value ce to the variable m of the electrode position coordinates Bxy (n, m) to which the X-direction electrode number gx equal to the variable k and the Y-direction electrode number gy equal to the variable s are assigned. Coordinate Bxy (n, m + ce) is newly defined, and X-direction electrode number gx equal to variable k and Y-direction electrode number gy equal to variable s + 1 are assigned to newly defined electrode position coordinate Bxy (n, m + ce), and variable Calculate the median value Avem (gy) of m. As a result, the electrode position coordinates Bxy (n, m) corresponding to the bus bar electrode 87 behind in the Y direction that has not been detected are supplemented, and the median value Avem is also calculated. Then, the controller 70 executes the processing after step S234 in FIG. 6E, but when the last one bus bar electrode 87 in the Y direction has not been detected as in the fifth column in the X direction in FIG. Since the variable s increased by the process of step S234 indicates the maximum value of the Y-direction electrode number gy, it is determined as “Yes” in step S242, and the process proceeds to step S226 and subsequent steps.

  However, if the last two bus bar electrodes 87 in the Y direction have not been detected as in the sixth column in the X direction in FIG. 12, it is again determined as “No” in step S <b> 242. The process consisting of steps S244 to S248 is executed, and the electrode position coordinates Bxy (n, m) corresponding to the bus bar electrode 87 behind the Y direction which has not been detected are further supplemented, and the median value Avem is also calculated. Is done. As a result, the electrode position coordinates Bxy (n, m) corresponding to all the bus bar electrodes 87 are supplemented. Further, even when the last three or more bus bar electrodes 87 in the Y direction are not detected, the processing including steps S244 to S248 described above is executed, and the bus bar electrodes behind the Y direction that have not been detected. The electrode position coordinate Bxy (n, m) corresponding to 87 is supplemented and its median value Avem is also calculated.

  Next, a case where the first bus bar electrode 87 in the Y direction is not detected as in the seventh and eighth rows in the X direction in FIG. 12 will be described. In this case, the solar cell SC does not exist in the vicinity of the Y-direction coordinate ny (= Avem (s) + ce) calculated by the process of step S244. Accordingly, in this case, the controller 70 determines “No” in step S246 and proceeds to step S250. In step S244, the controller 70 converts the X coordinate value n of the electrode position coordinate Bxy (n, m) assigned the X direction electrode number gx equal to the variable k and the Y direction electrode number gy equal to the variable s to the X direction coordinate. The value Avem (1) -ce obtained by subtracting the predetermined value ce from the median value Avem (1) is set as the Y-direction coordinate ny. Then, the maximum value is extracted from the current magnitude data Ixy (nx−a, ny−a) to Ixy (nx + a, ny + a) specified by the coordinates nx and ny to obtain the maximum current value Ismax. In this case, the value a is a predetermined value of about 5 to several tens. As a result, the maximum value of the current magnitude data Ixy (n, m) in a predetermined range of the position surrounding the central coordinate value of the electrode position coordinate Bxy (n, m) is set as the maximum current value Ismax. After the processing in step S250, the controller 70 determines in step S252 whether the maximum current value Ismax is greater than or equal to the set value, as in step S246.

  If the bus bar electrode is present at the position and the maximum current value Ismax is equal to or greater than the set value, the controller 70 determines “Yes” in step S252 and proceeds to step S254. This is processing when the first bus bar electrode 87 in the Y direction is not detected as in the seventh or eighth row in the X direction in FIG. In step S254, the predetermined value ce is subtracted from the variable m of the electrode position coordinate Bxy (n, m) to which the X-direction electrode number gx equal to the variable k and the Y-direction electrode number gy of “1” are assigned. The electrode position coordinate Bxy (n, m-ce) is newly defined, and the X-direction electrode number gx equal to the variable k is set to the newly defined electrode position coordinate Bxy (n, m-ce) and the Y direction is “1”. The electrode number gy is assigned, and the median value Avem (gy) of the variable m is calculated. As a result, the electrode position coordinates Bxy (n, m) corresponding to the bus bar electrode 87 ahead in the Y direction that has not been detected are supplemented, and the median value Avem is also calculated. After the process of step S254, the controller 70 determines in step S256 the electrode position coordinates Bxy (n, m) to which the X-direction electrode number gx equal to the variable k and the Y-direction electrode number gy equal to or greater than “2” are assigned. The Y direction electrode number gy is changed to the Y direction electrode number gy + 1. As a result, the electrode position coordinates Bxy (n, m) corresponding to the first bus bar electrode 87 in the Y direction in the seventh column in the X direction in FIG. 12 are supplemented, and the median value Avem is also calculated. The electrode number gy is also sequentially assigned to all electrode position coordinates Bxy (n, m) in the Y direction.

  Then, the controller 70 executes the processing after step S234 in FIG. 6E, but only the first bus bar electrode 87 in the Y direction has not been detected as in the seventh column in the X direction in FIG. Since the variable s increased by the process of step S234 indicates the maximum value of the Y-direction electrode number gy, it is determined as “Yes” in step S242, and the process proceeds to step S226 and subsequent steps.

  However, if the first two bus bar electrodes 87 in the Y direction have not been detected as in the eighth column in the X direction in FIG. 12, it is again determined as “No” in step S242, and is described above. The processing consisting of steps S250 to S256 is executed, and the electrode position coordinates Bxy (n, m) corresponding to the bus bar electrode 87 in the front in the Y direction that has not been detected are supplemented, and the median value Avem is also calculated. The As a result, the electrode position coordinates Bxy (n, m) corresponding to all the bus bar electrodes 87 are supplemented. Further, even when the first three or more bus bar electrodes 87 in the Y direction are not detected, the processing including steps S250 to S256 described above is executed, and the front bus bar electrode in the Y direction that has not been detected. The electrode position coordinate Bxy (n, m) corresponding to 87 is supplemented and its median value Avem is also calculated.

  Further, if “No” is determined in step S246 of FIG. 6F and “No” is also determined in step S252, the controller 70 proceeds to step S310 and subsequent steps in FIG. 6H. This is because when the electrode position coordinates Bxy (n, m) corresponding to the bus bar electrode 87 cannot be replenished, an abnormality has occurred in the solar cell inspection device, and the abnormality of the solar cell panel SP cannot be accurately detected. This is because the nature is high.

  Next, the process of steps S260 to S312 in FIG. 6G and FIG. 6H that performs the pass / fail determination of the solar battery panel SP and the image display of the current distribution will be described. First, in step S260, the controller 70 determines the magnitudes of all Y-direction currents corresponding to all the electrode position coordinate Bxy (n, m) groups to which the X-direction electrode number gx and the Y-direction electrode number gy are assigned. All the size data except for the size data Ixy (n, m) group corresponding to both ends of each size data Iy (n, m) group. The total average value Iavty of the Ixy (n, m) group is calculated. By this processing, in FIG. 7, the total average value Iavty of the current in the Y direction for each detection position of the current flowing through the bus bar electrode 87 excluding both ends of all the bus bar electrodes 87 is calculated. The reason for excluding both end portions of each size data Iy (n, m) group, that is, both end portions of the bus bar electrode 87, is that current may not be stable at both end portions. It is about 20 percent from percent.

  Next, in step S262, the controller 70 calculates all X-direction currents corresponding to all the electrode position coordinates Bxy (n, m) groups to which the X-direction electrode number gx and the Y-direction electrode number gy are assigned. A total average value Iavtx of the current magnitude data Ix (n, m) group in the X direction other than the magnitude data Ix (n, m) group is calculated. That is, from all the X-direction current magnitude data Ix (n, m) group, all the X-direction current magnitude data Ix (n, m) corresponding to all the electrode position coordinates Bxy (n, m) group. m) The average value Iavtx of the current magnitude data Ix (n, m) group in the X direction excluding the group is calculated. By this process, in FIG. 7, the total average value Iavtx of the current in the X direction flowing through the entire solar cell panel SP excluding the portion where all the bus bar electrodes 87 are located is calculated. In step S264, the controller 70 initializes the variables k, s, t, ep, and q to “1”. As shown in FIG. 7, the variable k is a variable that changes from 1 to kmax for designating the X-direction electrode number gx. The variable s is a variable that changes from 1 to smax for designating the Y-direction electrode number gy. The variable t is a variable that changes from 1 to tmax for designating the solar cell SC in the X direction. The variable ep is a variable for designating the bus bar electrode 87 in one solar battery cell SC, and is “1” or “2” in FIG. The variable q is a variable for designating the position of the bus bar electrode 87 in the longitudinal direction, and changes from “1” to “3” in the present embodiment.

  After the process of step S264, the controller 70 corresponds to the electrode position coordinate Bxy (n, m) to which the X-direction electrode number gx equal to the variable k and the Y-direction electrode number gy equal to the variable s are assigned in step S266. The Y-direction current magnitude data Iy (n, m) excluding both ends is extracted from the Y-direction current magnitude data Iy (n, m) as in the case of step S260. In step S268, the following calculation is executed using the extracted Y-direction current magnitude data Iy (n, m). First, as the average current flowing through one bus bar electrode 87 to which the X-direction electrode number gx equal to the variable k and the Y-direction electrode number gy equal to the variable s are assigned, the extracted Y-direction current magnitude data Iy (n , M), the average value Iavey is calculated. This average value Iavey is stored in RAM or a storage device as evaluation data A (t, s, ep) designated by variables t, s, and ep.

  Next, in step S268, the absolute value | Iavey | of the calculated average value Iavey is divided by the absolute value | Iavty | of the total average value Iavty calculated by the processing of step S260, and the division result | / | Iavty | is stored in the RAM or storage device as evaluation data B (t, s, ep) for evaluating the current level flowing through one bus bar electrode 87. Further, the minimum value is subtracted from the maximum value of the extracted Y-direction current magnitude data Iy (n, m), and the subtraction result is divided by the absolute value | Iavey | of the calculated average value Iavey. The division result (maximum value−minimum value) / | Iavey | is stored in RAM or a storage device as evaluation data C (t, s, ep) for evaluating the fluctuation of the current level flowing through one bus bar electrode 87. deep. Further, the standard deviation σ of the extracted Y-direction current magnitude data Iy (n, m) is divided by the absolute value | Iavey | of the calculated average value Iavey, and the division result σ / | Iavey | It is stored in RAM or a storage device as evaluation data D (t, s, ep) for evaluating the fluctuation of the current level flowing through one bus bar electrode 87.

  After the process of step S268, the controller 70 determines in step S270 whether or not the variable ep has reached the number of electrodes of the input solar cell SC. If the variable ep does not reach the number of electrodes of the solar battery cell SC, the controller 70 determines “No” in step S270, adds “1” to the variable ep in step S272, and in step S274. “1” is added to the variable k, and the process returns to step S266. And the process of step S266-274 is performed until the variable ep reaches the number of electrodes of the photovoltaic cell SC. Thereby, evaluation data A (t, s, ep), B (t, s, ep), C (t, s, ep) for each bus bar electrode 87 of one solar cell SC specified by the variables t, s. ), D (t, s, ep) are calculated and stored in the RAM or storage device.

  When the variable ep reaches the number of electrodes of the solar battery cell SC, the controller 70 determines “Yes” in step S270, and assigns the calculated X-direction electrode number gx and Y-direction electrode number gy in step S276. By using the evaluation data A (t, s, ep) relating to all the bus bar electrodes 87 of the solar cells SC obtained, the minimum value is subtracted from the maximum value and divided by the average value. Evaluation data E (t, s) for evaluating the variation in current between the bus bar electrodes 87 in the solar battery cell SC is calculated and stored in the RAM or the storage device.

  Next, in step S278, the controller 70 sets the electrode position coordinates Bxy (n, m) to which the X-direction electrode number gx equal to the value (k−ep + 1) and the Y-direction electrode number gy equal to the value s are assigned. Among all the coordinates (n, m) between the electrode position coordinates Bxy (n, m) to which the X-direction electrode number gx equal to the value k and the Y-direction electrode number gy equal to the value s are assigned. The current magnitude data Ix (n, m) in the X direction corresponding to the coordinates (n, m) where m is the value {Avem (s)-(2-q) · ce / 3} is extracted. Here, the extracted magnitude data Ix (n, m) in the X direction will be described. As shown in FIG. 7, the variable k designates the bus bar electrode 87 in the X direction, and the value ep represents the number of bus bar electrodes 87 in one solar cell SC (two in the example of FIG. 7). It is. At the time of the process in step S278, the variable k designates the last bus bar electrode 87 on the right side of each solar cell SC arranged in the X direction by the end of the circulation process in steps S266 to S274. It is the value of. Therefore, when processing the leftmost solar cell SC in FIG. 7, all the coordinates (n, m) in the X direction sandwiched between the positions of the bus bar electrodes 87 at both ends in the X direction of the leftmost solar cell SC. Among them, the coordinates of the position in the Y direction designated by the value {Avem (s) − (2-q) · ce / 3} are designated. The value Avem (s) represents the center position in the Y direction of the bus bar electrode 87 of the solar cell SC in the Y direction specified by the variable s, and the value ce is substantially equal to the length of the bus bar electrode 87 in the Y direction. First, when the variable q is “1”, the bus bar electrode from the center position in the Y direction of the bus bar electrode 87 among all the coordinates (n, m) in the X direction sandwiched between the positions of the bus bar electrode 87. Current magnitude data Ix (n, m) in the X direction corresponding to the coordinates (n, m) of the Y direction position that is smaller by 1/3 of the length of 87 is extracted.

  After the process of step S278, the controller 70 performs the following calculation using the extracted current magnitude data Ix (n, m) in the X direction in step S280. First, an average value Iavex of all the extracted size data Ix (n, m) is calculated. Next, the absolute value | Iavex | of the average value is divided by the absolute value | Iavtx | of the total average value of the current magnitude in the X direction calculated by the process of step S262, and the division result is obtained between the bus bar electrodes 87. Is stored in the RAM or storage device as evaluation value data F (t, s, q) for evaluating the current level.

  Next, the controller 70 determines whether or not the variable q has reached “3” in step S282. If the variable q does not reach “3”, the controller 70 determines “No” in step S282, adds “1” to the variable q in step S283, and performs the above-described steps S278 and S280. Execute the process. In this case, since the variable q is “2”, in the process of step S278, among all the coordinates (n, m) in the X direction sandwiched between the positions of the bus bar electrode 87, the Y of the bus bar electrode 87 is determined. The current magnitude data Ix (n, m) in the X direction corresponding to the coordinates (n, m) of the center position in the direction is extracted. With respect to the extracted magnitude data Ix (n, m), the average value Iavex is calculated by the processing in step S280, and the evaluation value data F (t, s, q) = | Iavex | / | Iavtx | is calculated and stored in the RAM or the storage device.

  Then, the determination process in step S282 is executed again. Also in this case, since the variable q has not reached “3”, the controller 70 executes the processes of steps S283, S278, and S280. In this case, since the variable q is set to “3”, in the process of step S278, the bus bar electrode out of all the coordinates (n, m) in the X direction sandwiched between the positions of the bus bar electrode 87. Current magnitude data Ix (n, m) in the X direction corresponding to the coordinate (n, m) of the Y direction position that is 1/3 of the length of the bus bar electrode 87 is extracted from the center position in the Y direction of 87. The In this case, the average value Iavex is also calculated for the extracted size data Ix (n, m) by the processing in step S280, and the evaluation value data F (t, s, q is calculated using the average value Iavex. ) = | Iavex | / | Iavtx | is calculated and stored in the RAM or the storage device. Since the variable q is “3” after the process in step S278, the controller 70 determines “Yes” in step S282, and proceeds to step S284 in FIG. 6H. At this time, the evaluation data A (t, s, ep), B (t, s, ep), C (t, s, ep) for one solar cell SC specified by the variables t, s. , D (t, s, ep), E (t, s), F (t, s, q) (q = 1 to 3) are stored in the RAM or storage device.

  In step S284, the controller 70 performs evaluation data B (t, s, ep), C (t, s, ep), D (t, s, ep) for the solar cell SC specified by the variables t and s. ), E (t, s), and F (t, s, q) (q = 1 to 3) are each determined as to whether they are larger than the allowable values. In this case, the allowable value is a value determined in advance for each evaluation data for determining the abnormality of the solar battery cell SC. Evaluation data B (t, s, ep), C (t, s, ep), D (t, s, ep), E (t, s), F (t, s, q) (q = 1) If any one of (3) to (3) is larger than the allowable value, the controller 70 determines “Yes” in step S284, and in step S286, the error data Er ( t, s) is set to “1” representing the abnormality of the solar battery cell SC, and the process proceeds to step S288. The error data Er (t, s) is initially set to “0” indicating normality. On the other hand, all evaluation data B (t, s, ep), C (t, s, ep), D (t, s, ep), E (t, s), F (t, s, q) (q = 1 to 3) is less than or equal to the allowable value, the controller 70 determines “No” in step S284 and proceeds to step S288.

  In step S288, the controller 70 determines whether or not the variable t has reached the input number tmax of solar cells SC in the X direction (see FIG. 7). If the variable t has not reached the number tmax of the solar cells SC in the X direction, the controller 70 determines “No” in step S288, adds “1” to the variable t in step S290, and performs step S292. The variables ep and q are returned to the initial value “1” and the process returns to step S274 in FIG. 6G. Then, the controller 70 repeatedly executes the processes of steps S266 to S283 of FIG. 6G and steps S284 and S286 of FIG. 6H described above to evaluate the evaluation data A (t, t of the solar cell SC specified by the variables t and s. s, ep), B (t, s, ep), C (t, s, ep), D (t, s, ep), E (t, s), F (t, s, q) (q = 1-3) and error data Er (t, s) are calculated and stored in the RAM or storage device. Then, the processes in steps S266 to S283 in FIG. 6G and steps S284 and S286 in FIG. 6H are performed until the variable t reaches the number tmax of the solar cells SC in the X direction, and the variable n is the solar cell in the X direction. When the SC number tmax is reached, the controller 70 determines “Yes” in step S288, and proceeds to step S294. As a result, the evaluation data A (t, s, ep), B (t, s, ep), C (t, s, ep), D (t, s, ep), E (t, s), F (t, s, q) (q = 1 to 3) and error data Er (t, s) are stored in the RAM or the storage device.

  In step S294, the controller 70 determines whether or not the variable s has reached the input number of solar cells SC in the Y direction smax (see FIG. 7). If the variable s has not reached the number smax of solar cells SC in the Y direction, the controller 70 determines “No” in step S294, adds “1” to the variable s in step S296, and in step S298. The variables k, t, ep, and q are returned to the initial value “1”, and the process returns to step S266 in FIG. 6G. Then, the controller 70 repeatedly executes the processes of steps S266 to S283 in FIG. 6G and steps S284 to S292 in FIG. 6H described above to evaluate the evaluation data A (t, t of the solar cell SC specified by the variables t and s. s, ep), B (t, s, ep), C (t, s, ep), D (t, s, ep), E (t, s), F (t, s, q) (q = 1-3) and error data Er (t, s) are calculated and stored in the RAM or storage device. Then, the processes in steps S266 to S283 in FIG. 6G and steps S284 to S292 in FIG. 6H are performed until the variable s reaches the number smax of solar cells SC in the Y direction, and the variable n is the solar cell in the Y direction. When the number of SCs smax is reached, the controller 70 determines “Yes” in step S294 and proceeds to step S300. As a result, evaluation data A (t, s, ep), B (t, s, ep), C (t, s, ep), D (t, s, ep) regarding all the solar cells SC in FIG. , E (t, s), F (t, s, q) (q = 1 to 3) and error data Er (t, s) are stored in the RAM or the storage device.

  In step S300, the controller 70 stores current magnitude data Ixy (n, m), current direction data θixy (n, m), current magnitude data Ix (X direction) stored in the RAM or storage device. n, m) and Y direction current magnitude data Iy (n, m) (n = 1 to N, m = 1 to M) are generated and displayed on the display device 72 by the image data. Displayed images. This image is displayed, for example, with different brightness and color according to the current magnitude data Ixy (n, m) for each inspection position of the solar cell SC, and the current direction data θixy (n, m, An arrow indicating the direction indicated by m) is displayed. Further, the brightness, color, and the like may be displayed in accordance with the current magnitude data Ix (n, m) in the X direction and the current magnitude data Iy (n, m) in the Y direction. In this case, when the bus bar electrode 87 is extended in the X direction and the variable CH is “1”, the display state of the current magnitude data Ixy (m, n) in the display device 72 is rotated by 90 degrees. .

  14A to 14C show display examples related to one solar cell SC. FIG. 14A is an example corresponding to the normality and disconnection abnormality of FIG. 10A. (A) is a case where the solar battery cell is normal, (B) is a case where a disconnection occurs in the surface side connection line on the left bus bar electrode 87 side, and (C) is a back surface on the left back electrode 81 side. This is a case where a break occurs in the side connection line. FIG. 14B is an example corresponding to the normality and resistance increase of FIG. 10B. (A) is a case where the solar cell is normal, (B) is a case where a 50 cm conductive wire is added as a surface side connection line on the left bus bar electrode 87 side, and (C) is a left bus bar electrode 87 side. This is a case where a lead wire of 150 cm is added as the surface-side connecting wire. FIG. 14C is an example corresponding to the normal state and the connection failure between the bus bar electrode 87 and the grid electrode 86 in FIG. 10B. (A) is a case where the solar cell is normal, and (B) is a case where the left bus bar electrode 87 and the grid electrode 86 are poorly connected.

  After the processing in step S300, in step S302, the controller 70 includes error data indicating “1” in the error data Er (t, s) (t = 1 to tmax, s = 1 to smax). Find out. If there is no error data indicating “1”, the controller 70 determines “No” in step S302, displays “pass” on the display device 72 in step S304, and evaluates this in step S314. Terminates program execution. On the other hand, if there is error data indicating “1”, the controller 70 determines “Yes” in Step S302, displays “Fail” on the display device 72 in Step S306, and in Step S308, The variables t and s whose error data E (t, s) is “1” are extracted, and the solar cell SC specified by the variables t and s in the displayed image is displayed as a defective solar cell SC. To do.

  Next, “Yes” is determined in step S156 in FIG. 6B, “No” is determined in step S222 in FIG. 6E, and “No” is determined in step S252 in FIG. 6F, and the processing in steps S310 and S312 in FIG. The case where it advanced is demonstrated. These are cases where the automatic pass / fail determination of the solar battery cell SC is impossible or highly possible due to an input error, an abnormality in the inspection device, or the like. Also in this case, the controller 70, in step S310, similarly to the processing in step S300, the current magnitude data Ixy (n, m), the current direction data θixy (n, m), and the current in the X direction. Display image data is generated from the magnitude data Ix (n, m) and the magnitude data Iy (n, m) (n = 1 to N, m = 1 to M) of the current in the Y direction, and the display device 72. The image represented by the image data is displayed on the screen. Next, in step S312, the controller 70 displays on the display device 72 that “success / failure determination of the solar battery cell SC is impossible”, and ends the execution of the evaluation program in step S314.

  In the embodiment that operates as described above, the light emitting element 50 has a predetermined cycle over the entire surface of the solar cell panel SP placed on the stage 40 by the drive control of the light emission signal supply circuit 65 and the light source drive circuit 66. Irradiate light with varying intensity evenly. Then, the X and Y direction slide mechanisms 20 and 30 scan the entire surface of the solar cell panel SP with the magnetic sensor 10, and the sensor signal extraction circuit 67 and the lock-in amplifier 68 flow through the solar cell panel SP by power generation. , And a magnetic field whose intensity changes with a period equal to the predetermined period is detected. Therefore, even if disturbance light or an external magnetic field exists, the magnetic field can be detected at a plurality of locations facing the solar cell panel SP without being affected by these costs while suppressing costs.

  And based on the said detection result, the controller 70 is the process of step S10-S41, S100-S124. Based on the detection result of the magnetic field in the several location which opposes solar cell panel SP, several of solar cell panel SP is obtained. The distribution of the magnitude of the current at the location is calculated. Therefore, even if ambient light or an external magnetic field is present, the cost can be suppressed and the distribution of current magnitudes at a plurality of locations of the solar cell panel SP can be accurately obtained without being affected by these effects. it can. Further, in the above-described embodiment, the controller 70 displays the calculated current magnitude distribution on the display device 72 by the processes of steps S300 and S310. As a result, the operator can visually recognize the distribution of current magnitudes at a plurality of locations of the solar cell panel SP, and can determine whether the solar cell panel SP is normal or abnormal from the distribution abnormality.

  Moreover, in the said embodiment, the controller 70 is based on distribution of the magnitude | size of the electric current in the several location of the said solar cell panel SP by the process of step S170-S214, S220-S256, S260-S298. Evaluation data B, C, D, E representing characteristics relating to the magnitude of the current flowing in each part in the extending direction of the bus bar electrode 87 and evaluation data representing characteristics relating to the distribution of the magnitude of the current flowing between the plurality of bus bar electrodes 87. In addition to calculating F, the evaluation data B, C, D, E, and F are used to automatically determine whether the solar cell panel SP is acceptable. These evaluation data B, C, D, E, and F show that, as a result of the experiment, the solar cell panel SP changes greatly from the normal state in an abnormal state where there is a disconnection between the electrodes, a poor contact between the electrodes, or the like. I know. Therefore, by using these evaluation data B, C, D, E, and F, the pass / fail judgment of the solar cell panel SP is accurately performed.

  Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the object of the present invention.

  In the above embodiment, the solar battery panel SP having the plurality of solar battery cells SC is inspected. However, the present invention can be applied to an inspection apparatus that individually inspects the solar cells SC instead.

  Moreover, in the said embodiment, regarding the distribution of the magnitude | size data Ix (m, n) of the electric current of the X direction between the bus-bar electrodes 87 of the both ends of one solar cell SC, the process of step S278-S282 of FIG. Thus, the distribution at three locations in the Y direction is calculated. However, this distribution may be one or two places less than three, or four or more places. Alternatively, the average of the current magnitude data Ix (m, n) in the X direction across the bus bar electrodes 87 at both ends of one solar cell SC may be calculated.

  Further, in the above-described embodiment, the current magnitude data in the processing of steps S170 to S214 in FIGS. 6C and 6D in which the X-direction electrode number gx and the Y-direction electrode number gy are assigned to the electrode position coordinates Bxy (n, m). The position of the bus bar electrode 87 is detected using Ixy (n, m). However, since the direction of the current flowing through the bus bar electrode 87 is substantially in the Y direction, the current magnitude data Iy (n, m) in the Y direction is used instead of the current magnitude data Ixy (n, m). You may make it use. Furthermore, in the above embodiment, the evaluation data A (t, s, ep), B (t, s, ep), C (t, s, ep), D (for evaluating the current flowing through the bus bar electrode 87 is used. In the processing of steps S260 and S266 to S276 in FIG. 6G for calculating t, s, ep) and E (t, s), current magnitude data Iy (n, m) in the Y direction is used. However, as described above, since the direction of the current flowing through the bus bar electrode 87 is substantially the Y direction, the current magnitude data Ixy (n, m) is substituted for the current magnitude data Iy (n, m) in the Y direction. n, m) may be used. Further, in the processing of steps S262 and S278 to S283 in FIG. 6G for calculating the evaluation data F (t, s, q), the current magnitude data Ix (n, m) in the X direction is used. However, since the direction of the current flowing between the bus bar electrodes 87 is mainly in the X direction, instead of the current magnitude data Ix (n, m) in the X direction, current magnitude data Ixy (n, m) May be used.

  Further, in the above embodiment and the modified example, the maximum value Hx of the X direction magnetic detection signal at the detection position of the magnetic sensor 10 and the phase shift amount with respect to the reference signal of the X direction magnetic detection signal are obtained by the processing of Steps S104 to S112 in FIG. θx, the maximum value Hy of the Y-direction magnetic detection signal, the phase shift amount θy with respect to the reference signal of the Y-direction magnetic detection signal, the magnetic field strength Hxy, and the magnetic field direction θxy are calculated, and the process of steps S112 and S114 is performed. The current magnitude Ixy (n, m) at the detection position of the sensor 10, the current direction θixy (n, m), the current magnitude Ix (n, m) in the X direction, and the current magnitude Iy in the Y direction (n, m) was calculated. The current magnitude Ixy (n, m), the current direction θixy (n, m), the X-direction current magnitude Ix (n, m), and the Y-direction current magnitude Iy (n , M), the evaluation data on the solar cell SC is calculated to evaluate the solar cell SC. However, the current magnitude Ixy is proportional to the magnetic field magnitude Hxy, and the current direction θixy only differs from the magnetic field direction θxy by π / 2. Therefore, the maximum value Hx of the X-direction magnetic detection signal, the maximum value Hy of the Y-direction magnetic detection signal, and the magnetic field strength Hxy at each detection position of the magnetic sensor 10 can be obtained without converting the information about the magnetic field into information about the current. By using instead of the current magnitude Ix (n, m), the current magnitude Iy (n, m) in the Y direction and the current magnitude Ixy (n, m) in the above embodiment, You may make it evaluate solar cell panel SP by calculating the evaluation data regarding each photovoltaic cell SC.

  Moreover, in the said embodiment, the position of the bus-bar electrode 87 was detected automatically, the evaluation data regarding the distribution of the magnitude | size of the electric current of the detected position was calculated, and the pass / fail judgment of each solar cell SC was performed. . However, instead, the operator looks at the current distribution image displayed on the display device 72 and instructs the position of the bus bar electrode 87 to the controller 70, and the controller 70 determines the magnitude of the current at the indicated position. You may make it perform the pass / fail determination of each photovoltaic cell SC by calculating the evaluation data regarding distribution. In addition, the controller 70 may calculate the evaluation data and display it on the display device 72 without performing the pass / fail determination, and allow the operator to perform the pass / fail determination of each solar cell SC. Further, the controller 70 displays the current distribution on the display device 72 as a graph as shown in FIG. 10 or an image as shown in FIG. 14 without calculating the evaluation data. You may make it determine the pass / fail of the cell SC.

  Moreover, in the said embodiment and modification, the stage 40 which mounted the magnetic sensor 10 was moved to the X and Y directions. However, instead of this, the stage on which the solar cell panel SP or the solar cell SC that is the inspection object is set may be moved together with the plurality of light emitting elements in the X and Y directions. Further, both stages may move in the X and Y directions. Furthermore, a large number of magnetic sensors 10 may be arranged in a matrix without moving the stage on which the magnetic sensor 10 and the solar cell panel SP (or solar cell SC) that is the inspection object are moved. .

  Moreover, in the said embodiment and modification, various evaluation data of solar cell panel SP or photovoltaic cell SC are calculated, and the pass / fail of solar cell panel SP or photovoltaic cell SC is determined with the value of various evaluation data. I made it. However, if the shape and size of the solar cell panel SP or solar cell SC to be inspected are limited to one, various calculation parameters (for example, current of the normal solar cell panel SP or solar cell SC). Comparison with magnitude data Ixy (m, n), current magnitude data Ix (m, n) in the X direction, current magnitude data Ix (m, n) in the Y direction, etc.) Or you may make it perform the pass / fail determination of the photovoltaic cell SC. Also, the current distribution (or magnetic field distribution) of the normal solar panel SP or solar cell SC is displayed together with the current distribution (or magnetic field distribution) of the solar panel SP or solar cell SC to be inspected. A person may be allowed to make a pass / fail judgment on the solar cell panel SP or the solar cell SC to be inspected by contrast observation.

  Moreover, in the said embodiment, although the light source which has arrange | positioned several light emitting element (LED) 50 in the matrix form was utilized, the light quantity on the stage 40 which sets the solar cell panel SP or solar cell SC which is a test object Any light source such as a fluorescent lamp or a lamp may be used as long as it becomes uniform.

  In the above embodiment, a magnetoresistive element (MR element) is used as the magnetic sensor. Instead, a Hall element, a magneto-impedance element effect sensor, a flux gate, a superconducting quantum interference element, or the like is used. May be.

DESCRIPTION OF SYMBOLS 10 ... Magnetic sensor, 20 ... X direction slide mechanism, 25 ... X direction motor, 30 ... Y direction slide mechanism, 34 ... Y direction motor, 40 ... Stage, 50 ... Light emitting element, 65 ... Light emission signal supply circuit, 67 ... Sensor Signal extraction circuit, 68 ... Lock-in amplifier, 70 ... Controller, 71 ... Input device, 72 ... Display device, 86 ... Grid electrode, 87 ... Busbar electrode, SP ... Solar ionization panel, SC ... Solar cell

Claims (3)

A light irradiation means for irradiating light whose intensity changes at a predetermined cycle over the entire surface of the solar battery panel or solar battery cell that is an inspection object in a state where a resistance is connected between the electrodes,
A magnetic field generated when a current flows through the inspection object due to light irradiation by the light irradiation means, and a magnetic field whose intensity changes with a period equal to the predetermined period is a plurality of magnetic fields facing the inspection object. Magnetic field detection means for detecting at a location ;
Based on the magnetic field detection results at a plurality of locations facing the inspection object detected by the magnetic field detection means, the current magnitude distribution at the plurality of locations of the inspection object or the inspection object is opposed. A distribution calculating means for calculating the distribution of the magnetic field strength at a plurality of locations;
Based on the distribution of the magnitude of current at a plurality of locations of the inspection object calculated by the distribution calculating means or the distribution of the strength of the magnetic field at a plurality of locations facing the inspection object, the plurality of electrodes. First characteristic value calculating means for calculating, for each electrode, a first characteristic value representing a characteristic relating to a distribution of magnitude of current flowing in each part in the extending direction or a distribution of magnetic field strength due to the current. A solar cell inspection apparatus characterized by that. A light irradiation means for irradiating light whose intensity changes at a predetermined cycle over the entire surface of the solar battery panel or solar battery cell that is an inspection object in a state where a resistance is connected between the electrodes,
A magnetic field generated when a current flows through the inspection object due to light irradiation by the light irradiation means, and a magnetic field whose intensity changes with a period equal to the predetermined period is a plurality of magnetic fields facing the inspection object. Magnetic field detection means for detecting at a location ;
Based on the magnetic field detection results at a plurality of locations facing the inspection object detected by the magnetic field detection means, the current magnitude distribution at the plurality of locations of the inspection object or the inspection object is opposed. A distribution calculating means for calculating the distribution of the magnetic field strength at a plurality of locations;
Based on the distribution of the magnitude of the current at a plurality of locations of the inspection object calculated by the distribution calculating means or the distribution of the strength of the magnetic field at a plurality of locations facing the inspection object, between the plurality of electrodes. A second characteristic value calculating means for calculating a second characteristic value representing a characteristic relating to a distribution of the magnitude of the current flowing through the magnetic field or a distribution of the intensity of the magnetic field caused by the current. Inspection device. In the solar cell inspection apparatus according to claim 1 or 2 ,
A solar cell inspection apparatus, comprising display means for displaying a current magnitude distribution or a magnetic field strength distribution calculated by the distribution calculating means.