Active voltage bus system and method

1. A voltage converter comprising:

an electric motor having a variable target DC voltage demand;

a first bidirectional voltage line arranged between a power source and said electric motor;

a second bidirectional voltage line arranged between said power source and said electric motor;

a power storage element arranged between said first bidirectional voltage line and said second bidirectional voltage line;

a switch element electronically coupled to said power storage element, said switch element operable to connect said power storage element with said second bidirectional voltage line;

a bidirectional converter operable to output a DC voltage less than a peak voltage on said first bidirectional voltage line; and

a controller operable to control said switch element, said controller comprising:

a multiplier operable to multiply a first voltage feedback signal from said first bidirectional voltage line between said power source and said power storage element by a difference between a second voltage feedback signal from said second bidirectional voltage line and a voltage reference, wherein said multiplier produces a multiplier output;

a first inverter operable to invert said multiplier output;

a second inverter operable to invert a current feedback signal from said power storage element;

a differential amplifier operable to amplify a difference between said first inverter output and said second inverter output;

a pulse width modulation generator operable to generate a pulse width modulated signal as a function of said differential amplifier output; and

a third inverter operable to invert said pulse width modulated signal;

wherein said inverted pulse width modulated signal is output to said switch element to adjust a current flow between said first bidirectional voltage line and said second bidirectional voltage line such that a voltage level on said second bidirectional voltage line is substantially maintained at said variable target DC voltage demand;

wherein said voltage converter is configured and arranged to dynamically change said DC voltage to said electric motor without a hardware reconfiguration, wherein real-time dynamic change of said DC voltage in a continuous transition to said electric motor is a function of operational parameters of said electric motor.

2. The voltage converter as set forth in claim 1 , and further comprising a bidirectional power factor correction stage, wherein said bidirectional power factor correction stage is configured and arranged to cause a power quality factor of the voltage converter to be approximately one.

3. The voltage converter as set forth in claim 1 , wherein said first bidirectional voltage line is an AC voltage line with multiple phases, and said voltage converter comprises a modular subcircuit for each phase of said AC voltage line.

4. The voltage converter as set forth in claim 3 , wherein each said modular subcircuit is connected in parallel.

5. The voltage converter as set forth in claim 3 , wherein each said modular subcircuit comprises a power factor correction circuit, a bidirectional isolation circuit, and said controller, said controller configured and arranged to provide pulse width modulated switch gating signals to said power factor correction circuit and said bidirectional isolation circuit.

6. The voltage converter as set forth in claim 5 , wherein said power factor correction circuit comprises a four switch H-bridge.

7. The voltage converter as set forth in claim 5 , wherein said bidirectional isolation circuit comprises an isolation transformer.

8. The voltage converter as set forth in claim 7 , and further comprising two four switch H-bridges.

9. The voltage converter as set forth in claim 5 , wherein: said controller is configured and arranged to provide switch gating signals to said power factor correction circuit to cause said voltage converter to have a power quality factor of approximately one; said controller is configured and arranged to provide switch gating signals to said bidirectional isolation circuit to cause said first bidirectional voltage line to be electrically isolated from said second bidirectional voltage line; and said controller is configured and arranged to cause said DC voltage on said second bidirectional voltage line to be at said variable target DC voltage demand.

10. The voltage converter as set forth in claim 5 , wherein each said power factor correction circuit configured and arranged to cause a current through said power storage element to be in phase with a voltage of said power storage element.

11. The voltage converter as set forth in claim 1 , wherein said voltage converter is configured and arranged for use in an aircraft.

12. The voltage converter as set forth in claim 1 , wherein said voltage converter is configured and arranged to transfer power from said electric motor to said power source during a regeneration phase.

13. The voltage converter as set forth in claim 1 , wherein said first bidirectional voltage line and said second bidirectional voltage line have no shared hardwire connection.