Compared with the almost long-time stuck power conversion efficiency of silicon photovoltaics, halide perovskites materials are today among the most promising lowcost candidates for solar power conversion due to their impressive efficiency increase over the last few years, starting from 3.8% (2009) to over 22.1.0% (2016) , very close to the research record of traditional silicon based solar cells (25.0%). Hence, they attract a huge interest, but nevertheless, for further improvement of the electrical and optical characteristics of the perovskite based solar cell, a deep understanding of the device physics, including band alignment, charge carrier traps and interfaces properties deserves consideration. In order to give a physical insight into the solar cell operation, a numerical simulation, using Silvaco-Atlas software, coupled with carriers drift and diffusion model and Poisson equation is proposed in our work. In addition to the current density versus voltage characteristic (JV) in dark or under AM1.5 sun illumination, the simulation of the capacitance versus voltage characteristic (CV) is performed and compared to experimental data. A realistic band diagram of the device is presented, and the effect of bulk and interface traps is studied. Moreover, the solutions for further efficiency enhancement are discussed.