OMD91046 rev D
10
1.1.1 Battery charger characteristic
A single-level charge is used. This is an optimal solution with sealed lead acid
batteries that, owing to the manufacturing technology, have a very narrow voltage
range. In fact, the nominal charging voltage ranges between 2.25÷2.27 V/cell, with a
maximum value of 2.3 V/cell. The picture below shows the charging curves at different
charging currents; the higher is the current, the higher is the restored capacity versus
time, the lower is the recharging time.
Picture 5 – Battery charger characteristic
1.2 INVERTER
The inverter converts the DC input voltage to AC voltage, stabilized in frequency and
RMS value.
The DC voltage is converted by the IGBT bridge, that uses two switches, controlled
using PWM (Pulse Width Modulation) technology at high commutation frequency. The
PWM generation as well as the control of the operating variables is completely
managed by the microprocessor.
Picture 6 – Inverter and static switch
