This paper presents a simulation model for a DC to DC boost converter. The simulation model was accomplished in MULTISIM 12 and represents in fact the electronic scheme which was manufactured experimentally in the Avionics Laboratory of our faculty. The converter amplifies the 24 VDC input to 48 VDC output, with a maximum power of 500 W. This converter can be used in the aero-spatial domain, on satellites, especially. In these cases it is integrated in energetic systems by the side of fuel cells, hydrogen and oxygen regeneration systems or photovoltaic cells. The command is a classic PWM with a switching frequency of 5 kHz and a linear variable voltage generator using also the 555 circuit. This paper is in fact a more detailed study using numerical simulations of this type of converters presented in [8]. Some improvements of the electronic scheme were achieved and the input and output voltages were modified in order to adapt to the avionics standards. From the numerical simulations one obtained the converters behavior under different loads -15 Ω and 35 Ω. The results are realistic and consistent with reality.