System and method for power sharing in a multiple UPS system

1. A load sharing system comprising:

a plurality of power supplies for powering a plurality of corresponding loads, each one of the plurality of power supplies being associated with at least one of the loads for powering its associated said load;

a power bus;

a plurality of inductors each connected to the power bus at first ends thereof, each one of the plurality of inductors further being connected at second ends to one another, and further coupled at the second ends to at least one of the loads and at least one of the power supplies, such that each adjacent pair of the inductors is connected in parallel relative to the at least one of the loads and to the at least one of the power supplies; and

each of the inductors having an inductance value sufficient so that if a fault develops on the power bus, each said inductor operates to isolate the power supplies from the power bus; and

the inductance value further being such that if any one of the power supplies fails, the specific adjacent pair of the inductors coupled in parallel to the one of the loads associated with the failed power supply allows the one load to draw power over the power bus from other ones of the power supplies through the specific adjacent pair of the inductors.

2. The load sharing system of claim 1 , wherein the power bus is comprised of first and second independent power busses.

3. The load sharing system of claim 2 , wherein the inductors of each said adjacent pair of the inductors are connected at the first ends thereof so that a first one of the adjacent pair is connected at the first end thereof to the first power bus, and the first end of a second one of the adjacent pair is connected to the second power bus.

4. A load sharing system comprising:

a plurality of power supplies for powering a plurality of corresponding loads, each one of the plurality of power supplies being associated with a given one of the loads for powering its associated said load;

a first power bus;

a second power bus;

a plurality of inductors connected to the first and second power busses and to the loads;

the plurality of inductors further being configured in a plurality of pairs such that each said pair of inductors is coupled at a first end thereof to one or the other of the first and second power busses such that each said pair of inductors has a first inductor of the pair coupled to the first power bus at the first end thereof, and a second inductor of the pair is coupled to the second power bus at the first end thereof,

and each said pair of inductors further being coupled to one another at second ends thereof, and at the second ends thereof in parallel to an associated one of the loads, and further in parallel at the second ends thereof to an associated one of the power supplies;

each said pair of inductors forming a parallel coupled pair of inductors relative to its associated said load and to its associated said power supply;

each of the inductors having an inductance value such that if a fault develops on the power bus, each said inductor operates to isolate the power supplies from the power bus; and

the inductance value further being such that if any one of the power supplies fails, the specific pair of inductors associated with the load of the failed power supply allows the load associated with the failed power supply to draw power from the power bus through the specific pair of inductors to power the load associated with the failed power supply.

5. A method for load sharing, comprising:

using a plurality of power supplies to power a plurality of corresponding loads, each one of the plurality of power supplies being associated with at least one of the loads for powering its associated said load;

using a power bus having first and second busses;

configuring pairs of inductors such that each said pair of inductors is in communication with a separate one of the first and second busses at first ends thereof;

configuring the pairs of inductors in parallel relative to each said load and relative to each said power supply, and further such each said pair of inductors is coupled together at second ends thereof, and

further coupled at the second ends thereof to an associated with a given one of the loads, and

further coupled at the second ends thereof to a given one of the power supplies;

selecting a common value of inductance for each of the inductors, the common value of inductance being sufficient so that if a fault develops on the power bus, at least one said inductor of each said pair of inductors operates to isolate its associated said power supply from the power bus; and

the common value of inductance further being such that if any one of the power supplies fails, the one pair of inductors coupled in parallel to the one of the loads associated with the failed power supply allows the one load to draw power over the power bus from other ones of the power supplies through the one pair of inductors.