Abstract: An electrical distribution box for vehicles with two networks at different voltage levels, comprising centralized electronic signal and power control means, including a microprocessor and electrical protection means, arranged on printed circuit boards in a casing, electrically connected to at least one DC supply source and to parts of the vehicle, incorporating at least one voltage converter (5) inside the distribution box (1), on an independent printed circuit board (10) or in a differentiated area of a supporting plate of the control means, which board (10) or differentiated area is in a clear area of said casing, both in its upper part and in its lower part, electromagnetic screening means having been provided for the converter (5) inside the casing, and thermal dissipation means for the supporting plate of the converter (5).

Abstract: Based on the measurement of the increase of sinusoidal voltage ?V=Vmaxsine(2?ft) on adding a sinusoidal current ?I=Imaxsine(2?ft+?) to the battery current, where f is the frequency and Imax, the amplitude of the superimposed current, with whose magnitudes the electrochemical impedance of the battery Z(f)=Vmax/Imaxej? is calculated, comprising the application of a first sinusoidal signal of prefixed frequency to the battery which generates an alternate voltage component superimposed over the direct one; eliminating the direct component of the response signal; applying a second periodic voltage signal with a frequency identical to that of said first signal and carrying out a synchronous detection of the alternate component generated by the application of said first signal to obtain the voltage proportional to the electrochemical impedance and evaluate the state of health and charge of the battery.

Abstract: The invention is designed for vehicles having two electrical power supply systems and corresponding differentiated voltage level charges and two batteries operating at a first and a second voltage level. A bidirectional voltage converter cooperates with both systems whose input and output stages are galvanically insulated and include a switch. The batteries are connected to said input and output at a first and a second voltage level so that said bidirectional converter can provide a first reduced voltage mode and a second increased voltage mode. The passive components, e.g. the magnetic components and capacitances, of said stages have been chosen to provide an identical transitional behavior in both modes when a disruption occurs in the regulating system either in the charge or the input voltage.