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Newton-Raphson method is one of the widely used iterative computational techniques for deducing the solution of non-linear transcendental equations. This is due to its simplicity, robustness, fast convergence among various numerical techniques [8]. The generalized equation representing the solution of non-linear equations using NR method can be expressed as:

(1.31)

Employing this method with the initial guess values obtained using equations given in section 1.2.1 and substitution of parameters like V_oc, I_sc, V_mpp, I_mpp and N_s from data sheet in the transcendental equations from (1.10), (1.11) and (1.13). Equation (1.31) can be written as,

(1.32)

The deduced values of V_t, R_se and R_sh are used to calculate I_LG and I_sat using (1.4) and (1.5). Similarly, the calculations are performed for estimating the parameters under dynamic environmental conditions of varying irradiance and temperature to estimate the maximum power from the panel. To achieve this, initially the open circuit voltage V_oc(G) of PV panel under varying irradiance condition need to be estimated using (1.22) by NR technique. Then, the obtained values are used to estimate the five unknown parameters of SDM under dynamic conditions using equations (1.23) to (1.27), respectively. The simplified steps in solving the transcendental equation using NR technique with error tolerance of 10^-6 is given in the form of flowchart as shown in Figures 1.2 and 1.3 for STC and dynamic environmental conditions, respectively. Unlike Gauss-Seidel technique, there is no need for any additional techniques such as SUR technique to solve the equations (1.28) & (1.29) which adds more value to the NR approach.