This paper presents a methodology for the extraction of parameters of photovoltaic (PV) modules through the use of electric models with single and double exponentials. The aim of the proposed method was extract the parameters directly from measured curves applying the Trust Region Method to solve a system of equations f(x i ). The variables x i are the photocurrent (I ph ), the reverse saturation current (I o ), the ideality factor (A i ), series resistance (R s ) and the shunt resistance (R sh ). The validation method is made by approximating the IV curves using the calculated parameters. So, is provided a statistical analysis of errors from the curves obtained in a way to assess the feasibility of the method. A comparison between the results obtained through the two circuit models is also provided.