Maximum power point tracking (MPPT) techniques are used in photovoltaic (PV) systems to maximize the PV array output power by tracking continuously the maximum power point (MPP), which depends on panels' temperature and irradiance conditions. The perturb and observe (P&O) MPPT algorithm is the most commonly used method due to its ease of implementation. However, it has some drawbacks such as the oscillation of the operating point around the MPP at steady state, which raises the waste of some amount of available energy. In addition, the P&O algorithm can be confused by rapidly changing atmospheric conditions. In this paper the P&O MPPT parameters are optimized to the dynamic behavior of the PV system, in order to limit the negative effects of the above drawbacks. The theoretical analysis is presented for non-ideal DC-DC converter connected to Standalone AC load (off grid) PV system to obtain the optimal choice of two main P&O algorithm parameters, the amplitude of the duty cycle perturbation, and the sampling interval. Also the study is compared with the analysis of the ideal converters to clarify the effect of non-ideality on the parameters design. Finally, simulation results are presented as confirmation of the theoretical analysis.