Power supply system with two batteries of different voltage
AssigneeSiemens Aktiengesellschaft
InventorJohannes Ilg
Life of this patent
Estimating the term…
Abstract
A power supply system contains two batteries and a load device which is connected to the batteries such that, upon failure of one of the batteries, the other takes over the supply of power. The batteries and the load device are connected to one another by a single ground line and arranged such that, upon an interruption between the interconnected grounds of the batteries and the ground of the load device, the load device is fed with the difference voltage of the batteries. A reliably operating power supply system is created which is operational by with only one ground line.
Claims17
A power supply system, the system comprising:
- a first battery connected to a first line at a first voltage relative to ground;
- a second battery connected to a second line at a second voltage relative to ground;
- a load device having a third line adapted to be connected to one of the first and second lines and having a fourth line adapted to be connected to ground;
- and
- a set of diodes associated with the load device, the set of diodes including:
- a first diode permitting current flow from the first line to the third line when the first voltage is greater than the second voltage;
- a second diode permitting current flow from the second line to the third line when the second voltage is greater than the first voltage;
- a third diode permitting current flow from the fourth line to the second line when i) the first voltage is greater than the second voltage and ii) the fourth line is disconnected from ground;
- and
- a fourth diode permitting current flow from the fourth line to the first line when i) the second voltage is greater than the first voltage and ii) the fourth line is disconnected from ground.
A power supply system for connecting a first battery and a second battery to a load device, each of the batteries having a positive terminal and a negative terminal, and the load device having an inlet and an outlet, the system comprising:
- a first diode having a first anode adapted to be connected to the positive terminal of the first battery and a first cathode adapted to be connected to the input of the load device;
- a second diode having a second anode adapted to be connected to the positive terminal of the second battery and a second cathode adapted to be connected to the input of the load device;
- a third diode having a third anode adapted to be connected to the output of the load device and a third cathode adapted to be connected to the positive terminal of the first battery;
- and
- a fourth diode having a fourth anode adapted to be connected to the output of the load device and a fourth cathode adapted to be connected to the positive terminal of the second battery.
A method of supplying power from first and second batteries to a load device, the first battery having a first voltage relative to ground, the second battery having a second voltage relative to ground, and the load device having an inlet and outlet, the method comprising:
- supplying a first current to the load device inlet from the first battery when the first voltage is greater than the second voltage;
- supplying a second current to the load device inlet from the second battery when the second voltage is greater than the first voltage;
- connecting the second battery in series between the output of the load device and the first battery when i) the first voltage is greater than the second voltage and ii) a common ground between the load device and the two batteries is broken;
- and
- connecting the second battery in series between the first battery and the input of the load device when i) the second voltage is greater than the first voltage and ii) the common ground is broken.
Dependencies are inferred from the claim text.