Topic Battery Charger/Design1

Designing rectifier transformer for battery charger 6Vdc, 40dc

Input parameters

Input Voltage 120V, +-10%, 60Hz, sine wave
  Wire Al, round, single insulated
Output Nominal DC output voltage 6.3Vdc, via central tap, one phase rectifier with 2 diodes
  Nominal DC output current 40Adc, via central tap, one phase rectifier with 2 diodes
  Wire Al, round, single insulated, wound bifilar
Core Steel M19, alternate stacking, not annealed
Bobbin Type Single section
Design Insulation class B, max. operating temperature 120C
  Criterion of design 16.6% regulation of the DC output voltage for battery charging between 2.45V/cell and 2.1V/cell
  Ambient temperature 40C

General rules

1. The cell voltage of an empty battery has amount of 2.1Vdc. If it is full then the voltage is between 2.35Vdc and 2.45Vdc per cell. The criterion of design has to be

Regulation: Regulation = 100 x (2.45-2.1)/2.2 = 16.6%

2. Due to the fact that the allowed regulation is relatively low we have to use only single section bobbin.

3. The transformers with Al wires are bigger, cooler but cheaper.

Diagnose Input and Circuit CORE/BOBBIN/STEEL/CASE Ceneral Data