Electric power generating system for multiple sources and interface to an AC grid

1. An electric power generating system comprising:

a plurality of variable power sources including at least one source of DC power and at least one source of AC power;

upstream converters for converting power supplied by said plurality of power sources to a common source of power communicated to a common collector bus;

a power grid for supplying three-phase power to components requiring three-phase power, and downstream on said common collector bus;

downstream converters for providing said three phases of power to said power grid from said common collector bus;

said common collector bus being a high voltage DC bus;

a DC link inverter being positioned intermediate said common collector bus and said downstream converters, and said DC link inverter providing power to motor driven loads;

said downstream converters being DC to AC converters with modulation to change DC power from said common collector bus to a phase of AC power for delivery to said three-phase power grid; and

said converters including a high frequency converter, a transformer, and a single pole bi-directional switch, and there are at least 3 of said converters to provide 3 phases of AC power.

2. The system as set forth in claim 1 , wherein said multiple power sources include a fuel cell, energy storage elements, and photovoltaic elements as said sources for supplying DC power.

3. The system as set forth in claim 2 , wherein said multiple power sources include at least one of a gas turbine engine and an internal combustion engine communicating with a generator to provide said at least one source of AC power.

4. The system as set forth in claim 1 , wherein said multiple power sources include at least one of a gas turbine engine and an internal combustion engine communicating with a generator to provide said at least one source of AC power.

5. An electric power generating system comprising:

a plurality of variable power sources including at least one source of DC power and at least one source of AC power;

upstream converters for converting power supplied by said plurality of power sources to a common source of power communicated to a common collector bus;

a power grid for supplying three-phase power to components requiring three-phase power, and downstream on said common collector bus;

downstream converters for providing said three phases of power to said power grid from said common collector bus; and

said common collector bus including a high frequency single phase constant voltage bus.

6. The system as set forth in claim 5 , wherein cycloconverters communicate power from said common collector bus to motor driven loads.

7. The system as set forth in claim 6 , wherein the three-phase power delivered to the said power grid are created by single phase cycloconverters.

8. An electric power generating system comprising:

a plurality of variable power sources including at least one source of DC power and at least one source of AC power;

upstream converters for converting power supplied by said plurality of power sources to a common source of power communicated to a common collector bus;

a power grid for supplying three-phase power to components requiring three-phase power, and downstream on said common collector bus;

downstream converters for providing said three phases of power to said power grid from said common collector bus; and

said common collector bus is a high frequency three-phase common collector bus modulated by half wave sinusoidal waveform with the frequency equal to twice the power grid frequency.

9. The system as set forth in claim 8 , wherein said downstream converters are single phase reduced component set inverters.

10. The system as set forth in claim 9 , wherein said single phase reduced component set inverters include a single pole bi-directional switch.

11. The system as set forth in claim 8 , wherein a plurality of motor driven loads are supplied with power through an AC-DC-AC motor drive inverter from said power grid.