For Output Voltage Stabilization
The output voltage of a battery charger with parallel connected battery varies substantially with the charging condition of the battery. For many applications however, the load circuit requires a better stabilized voltage. Frequently used methods for reducing the voltage variation are “voltage dropping diodes” or “systems with main and end cells”. A more economical solution is given by switching mode step-up converters. These are DC/DC converters supplied by the battery with the output connected in series to the battery. Due to the circuit configuration, the output of a step-up converter is not insulated from the input supply (battery).
Create Your Step-up Converter
The step-up converters are very similar to the DC/DC converters of series “C”, with the specialty that the set-up converters sense the voltage across the load which is the total of the battery voltage and the voltage added by the step-up converter. Therefore,each DC/DC converter can be modified to be a step-up converter:
- Calculate the output power of the step-up converter: max. voltage to be added x max. load current
- Choose the suitable “C” series
- Re-name the model as “E” …
The step-up converter cannot reduce the voltage being applied to its input. Therefore, the load should be specified for the maximum battery voltage.