Battery charger with a plurality of secondary transformer circuits
The present disclosure relates to a battery charger ( 100 ). The battery charger ( 100 ) includes a charging circuit ( 110 ) which comprises a primary transformer circuit ( 200 ) connectable to a power source ( 120 ) to receive charging current from the power source ( 120 ) and a plurality of secondary transformer circuits ( 210,220 ). At least one of the plurality of secondary circuits ( 210, 220 ) is arranged to cooperate with the primary transformer circuit ( 200 ) to provide a charging voltage to at least one battery ( 130 ), and the plurality of secondary transformer circuits ( 210,220 ) are connected in series with each other. A first secondary transformer circuit ( 210 ) is configured to provide a first charging voltage to the at least one battery ( 130 ) by means of a first associated output ( 10 ). At least one second secondary transformer circuit ( 220 ) is configured to provide an additive charging voltage, which is added to the first charging voltage from the first secondary transformer circuit ( 210 ) to form a second charging voltage. The second charging voltage is provided to the at least one battery ( 130 ) by means of a second associated output ( 20 ).
1. A battery charger, wherein the battery charger includes a charging circuit which comprises:
a primary transformer circuit connectable to a power source to receive charging current from the power source; and
a plurality of secondary transformer circuits, wherein at least one of the plurality of secondary circuits is arranged to cooperate with the primary transformer circuit to provide a charging voltage to at least one battery, and wherein the plurality of secondary transformer circuits are connected in series with each other; and wherein
a first secondary transformer circuit is configured to provide a first charging voltage to the at least one battery by means of a first set of terminals defining a first output, and
at least one second secondary transformer circuit is configured to provide an additive charging voltage, which is added to the first charging voltage from the first secondary transformer circuit to form a second charging voltage, wherein the second charging voltage is provided to the at least one battery by means of a second set of terminals defining a second output,
wherein the battery charger further comprises a charge control circuit connected to the charging circuit, and wherein the charge control circuit is arranged to identify which one of the first and second outputs the at least one battery is connected to, and
wherein the charge control circuit is arranged to identify the which one of the first and second outputs the at least one battery is connected to by communication with the at least one battery.
2. The battery charger according to claim 1 , wherein the first charging voltage is of a Safety Extra Low Voltage, SELV, class.
3. The battery charger according to claim 1 , wherein the same Volt-Ampere, VA, ratings are used on the first and second outputs of the plurality of secondary transformer circuits as for the primary transformer circuit.
4. The battery charger according to claim 1 , wherein the current rating at the first output of the first secondary transformer circuit is the same as the current rating at the second output of the at least one second secondary transformer circuit.
5. The battery charger according to claim 1 , wherein the charge control circuit is arranged to identify the which one of the first and second outputs the at least one battery is connected to by sensing where battery voltage is present.
6. The battery charger according to claim 1 , wherein the charge control circuit is arranged to use voltage feedback from the at least one second secondary transformer circuit when the at least one battery is identified to be connected to the second output.
7. The battery charger according to claim 1 , wherein the battery charger is arranged to keep the voltage level at the first output within a Safety Extra Low Voltage, SELV, level, when the at least one battery is identified to be connected to the second output.
8. The battery charger according to claim 1 , wherein the charge control circuit is arranged to use voltage feedback from the first secondary transformer circuit when the at least one battery is identified to be connected to the first output.
9. The battery charger according to claim 1 , wherein the charging circuit further comprises regulating means and wherein said regulating means is connected, and shared, between the first secondary transformer circuit and at least one of the said at least one secondary transformer circuit.
10. The battery charger according to claim 9 , wherein said shared regulating means is at least one of an output fuse, a safety output control relay and a current shunt.
11. The battery charger according to claim 1 , wherein the battery charger is based on AC/DC power conversion.
12. The battery charger according to claim 1 , wherein the battery charger is based on DC/DC power conversion.
13. The battery charger according to claim 1 , wherein the battery charger is arranged for use with re-chargeable lithium ion batteries.
14. A battery charger, wherein the battery charger includes a charging circuit which comprises:
a primary transformer circuit connectable to a power source to receive charging current from the power source; and
a plurality of secondary transformer circuits, wherein at least one of the plurality of secondary circuits is arranged to cooperate with the primary transformer circuit to provide a charging voltage to at least one battery, and wherein the plurality of secondary transformer circuits are connected in series with each other; and wherein
a first secondary transformer circuit is configured to provide a first charging voltage to the at least one battery by means of a first set of terminals defining a first output, and
at least one second secondary transformer circuit is configured to provide an additive charging voltage, which is added to the first charging voltage from the first secondary transformer circuit to form a second charging voltage, wherein the second charging voltage is provided to the at least one battery by means of a second set of terminals defining a second output,
wherein a charge control circuit is connected to the charging circuit and is arranged to identify the which one of the first and second outputs the at least one battery is connected to by communication with the at least one battery.
15. A battery charger, wherein the battery charger includes a charging circuit which comprises:
a primary transformer circuit connectable to a power source to receive charging current from the power source; and
a plurality of secondary transformer circuits, wherein at least one of the plurality of secondary circuits is arranged to cooperate with the primary transformer circuit to provide a charging voltage to at least one battery, and wherein the plurality of secondary transformer circuits are connected in series with each other; and wherein
a first secondary transformer circuit is configured to provide a first charging voltage to the at least one battery by means of a first set of terminals defining a first output, and
at least one second secondary transformer circuit is configured to provide an additive charging voltage, which is added to the first charging voltage from the first secondary transformer circuit to form a second charging voltage, wherein the second charging voltage is provided to the at least one battery by means of a second set of terminals defining a second output,
wherein a charge control circuit is connected to the charging circuit and is arranged to identify the which one of the first and second outputs the at least one battery is connected to by sensing where battery voltage is present.