I-V characteristic measuring apparatus and I-V characteristic measuring method for solar cell, and recording medium recorded with program for I-V characteristic measuring apparatus

An I-V characteristic measuring method for a solar cell, the method comprising:

• measuring a light state forward I-V characteristic that is an I-V characteristic of the solar cell measured in a light state where the solar cell is irradiated with pseudo-sunlight and in a forward sweep mode in which applied voltage to the solar cell is swept from a short-circuit current side to an open-circuit voltage side within a predetermined time;
• measuring a light state reverse I-V characteristic that is an I-V characteristic of the solar cell measured in the light state and in a reverse sweep mode in which the applied voltage to the solar cell is swept from the open-circuit voltage side to the short-circuit current side within the predetermined time;
• measuring a dark state forward I-V characteristic that is an I-V characteristic of the solar cell measured in a dark state where the solar cell is not irradiated with the pseudo-sunlight and in the forward sweep mode;
• measuring a dark state reverse I-V characteristic that is an I-V characteristic of the solar cell measured in the dark state and in the reverse sweep mode;
• measuring a dark state stationary I-V characteristic that is an I-V characteristic of the solar cell measured in the dark state and in a stationary sweep mode in which the applied voltage to the solar cell is swept between the short-circuit current side and the open-circuit voltage side over a time longer than the predetermined time;
• calculating an internal division ratio at which a current value of the dark state stationary I-V characteristic internally divides a gap between a current value of the dark state forward I-V characteristic and a current value of the dark state reverse I-V characteristic at each voltage value;
• and
• estimating and calculating a light state stationary I-V characteristic that is an I-V characteristic measured in the light state and in the stationary sweep mode on a basis of the internal division ratio, the light state forward I-V characteristic, and the light state reverse I-V characteristic.

A recording medium recorded with a program used for an I-V characteristic measuring apparatus for a solar cell, the I-V characteristic measuring apparatus comprising:

• a light state forward I-V characteristic storage part that stores a light state forward I-V characteristic that is an I-V characteristic of the solar cell measured in a light state where the solar cell is irradiated with pseudo-sunlight and in a forward sweep mode in which applied voltage to the solar cell is swept from a short-circuit current side to an open-circuit voltage side within a predetermined time;
• a light state reverse I-V characteristic storage part that stores a light state reverse I-V characteristic that is an I-V characteristic of the solar cell measured in the light state and in a reverse sweep mode in which the applied voltage to the solar cell is swept from the open-circuit voltage side to the short-circuit current side within the predetermined time;
• a dark state forward I-V characteristic storage part that stores a dark state forward I-V characteristic that is an I-V characteristic of the solar cell measured in a dark state where the solar cell is not irradiated with the pseudo-sunlight and in the forward sweep mode;
• a dark state reverse I-V characteristic storage part that stores a dark state reverse I-V characteristic that is an I-V characteristic of the solar cell measured in the dark state and in the reverse sweep mode;
• and
• a dark state stationary I-V characteristic storage part that stores a dark state stationary I-V characteristic that is an I-V characteristic of the solar cell measured in the dark state and in a stationary sweep mode in which the applied voltage to the solar cell is swept between the short-circuit current side and the open-circuit voltage side over a time longer than the predetermined time, wherein
• the program used for an I-V characteristic measuring apparatus fulfills functions as:
• an internal division ratio calculation part that, at each voltage value, calculates an internal division ratio at which a current value of the dark state stationary I-V characteristic internally divides a gap between a current value of the dark state forward I-V characteristic and a current value of the dark state reverse I-V characteristic;
• and
• a light state stationary I-V characteristic estimation and calculation part that, on a basis of the internal division ratio, the light state forward I-V characteristic, and the light state reverse I-V characteristic, estimates and calculates a light state stationary I-V characteristic that is an I-V characteristic measured in the light state and in the stationary sweep mode.