Linear Temperature Dependence of Diode Ideality Factor Calculation
This algorithm calculates the linear temperature dependence of the diode ideality factor. In general, it does this by determining a value that results in a temperature coefficient of maximum power as close as possible to the datasheet input.
- Determine the direction that mu gamma should increment.
The linear temperature dependence of gamma is incremented once in both the positive and negative directions, creating a set of three values:
For each of these values, γ is temperature adjusted to 45⁰C, in addition to temperature adjusting all of the other single diode parameter inputs (see the algorithm documentation section entitled “One-Diode Model Temperature Correction”).
Calculate Pmp at STC then for each of the three mu gamma values, calculate Pmp at 45⁰C and calculate mu_Pmp using the following equation:
If the error between calculated mu_Pmp and mu_Pmp from the datasheet input decreases for mu_gamma + increment, then mu_gamma should be incremented in the positive direction to achieve the optimal value.
- Iterative increment to the optimal value that generates close to the inputted value of mu_Pmp.
Increment mu_gamma in the direction determined in step 1, performing a similar calculation to step 1 and checking the error between calculated_mu_Pmp and mu_Pmp at each iteration. The optimal value of mu_Pmp that which precedes the error between calculated_mu_Pmp and mu_Pmp starting to increase.