JV
Every measurement start with a JV scan to obtain the device's key parameters such as Voc1, Jsc2 and MPP3. If tracking is enabled, a JV scan is repeated a fixed intervals to obtain these parameters over time.
A staircase voltage ramp is applied from the start to the end voltage. The time each point is applied is determined by step size / scan rate.
Parameters¶
After a JV scan is completed, the following parameters are extracted. All parameters are saved in each JV file.
- Voc1: The voltage at which current is 0 A.
- Jsc2: The current at which voltage is 0 V.
- V_MPP: The voltage at the MPP3
- J_MPP: The current at the MPP3
- P_MPP: The power at the MPP (V_MPP * J_MPP)
- Fill Factor: P_MPP / (Voc * Jsc)
- Efficiency: P_MPP / I_Incident
- R_series: 1/slope at Voc
- R_shunt: 1/slope at Jsc
R calculation
The resistance calculation at Voc and Jsc are done with 10% of the JV range. e.g. if the JV is done from -0.2 V to 1.2 V, the taken range is (1.2 - -0.2) * 0.1 = 0.14 V.
JV Parameters Reference¶
