Hybrid variable speed generator/uninterruptible power supply power converter

• US 20040084965A1
• Filed: 10/22/2003
• Published: 05/06/2004
• Est. Priority Date: 10/22/2002
• Status: Abandoned Application

• Current Assignee: Youtility Incorporated
• Original Assignee: Youtility Incorporated
• Inventors: LeRow, Kevin E., Wen, Jian, Welches, Richard Shaun, Griessel, Richard, Hohm, Daniel P.
• Application Number:
  US10/691,357
• Publication Number:
  US 20040084965A1
• Time in Patent Office: Days
• US Class Current: 307/64
• CPC Class Codes: H02J 3/00125 Transmission line or load transient problems, e.g. overvoltage, resonance or self-excitation of inductive loads H02J3/01 takes precedence
• CPC Class Codes: H02J 3/01 Arrangements for reducing harmonics or ripples
• CPC Class Codes: H02J 3/1842 wherein at least one reactive element is actively controlled by a bridge converter, e.g. active filters
• CPC Class Codes: H02J 3/1864 wherein the stepless control of reactive power is obtained by at least one reactive element connected in series with a semiconductor switch
• CPC Class Codes: H02J 3/30 using dynamo-electric machines coupled to flywheels
• CPC Class Codes: H02J 9/062 for AC powered loads
• CPC Class Codes: H02J 9/066 characterised by the use of dynamo-electric machines H02J9/08 takes precedence
• CPC Class Codes: H02M 5/458 using semiconductor devices only
• CPC Class Codes: Y02E 40/10 Flexible AC transmission systems [FACTS]
• CPC Class Codes: Y02E 40/20 Active power filtering [APF]
• CPC Class Codes: Y02E 40/40 Arrangements for reducing harmonics
• CPC Class Codes: Y02E 60/16 Mechanical energy storage, e.g. flywheels or pressurised fluids

Abstract

The invention in the simplest form is an improved hybrid power converter with uninterruptible power supply (UPS) and power quality capabilities as well as an integrated variable speed power source and control method that is used to generate high quality, uninterruptible AC power utilizing fewer batteries and operating at optimum fuel efficiency and with reduced emissions. The variable speed generator control scheme allows for load adaptive speed control of a power source such as an engine and generator. The transformerless hybrid power converter topology and control method provides the necessary output frequency, voltage and/or current waveform regulation, harmonic distortion rejection, and provides for single-phase or unbalanced loading. The transformerless hybrid power converter also provides inline or offline UPS capability, line voltage and/or frequency sag and surge compensation, peak shaving capability, VAR compensation and active harmonic filtering.

Claims

12. A method for providing uninterruptible AC power to a load, comprising:

coupling an AC line to a hybrid uninterruptible power supply;

coupling said hybrid uninterruptible power supply to said load, wherein said hybrid uninterruptible power supply comprises a regulator section, an inverter and an energy storage module; and

switchably coupling a variable speed energy source to said hybrid uninterruptible power supply.

1. A hybrid power converter apparatus, comprising:

a variable speed energy generating device producing differing amounts of power at different speeds;

a hybrid uninterruptible power supply coupled in-line between an AC line and a load, wherein said hybrid uninterruptible power supply is switchably coupled to said variable speed energy generating device, wherein said hybrid uninterruptible power is comprised of a regulator section coupled to an inverter and an energy storage module coupled therebetween.

2. The apparatus according to claim 1, wherein said inverter is selected from the group consisting of:

transformerless AC pulse width modulator inverter, DC-AC inverter, static inverter, rotary converter, cycloconverter, and AC-AC motor generator set.

3. The apparatus according to claim 1, wherein the variable speed energy generating device is selected from the group consisting of:

internal combustion engine, turbine, micro-turbine and Stirling engine.

4. The apparatus according to claim 1, wherein said regulator section is an enhanced conduction angle dual boost DC bus voltage regulator.

5. The apparatus according to claim 1, further comprising a switch between said inverter and said load.

6. The apparatus according to claim 1, further comprising a switch coupling said hybrid uninterruptible power supply to said AC line.

7. The apparatus according to claim 1, wherein said energy storage module, is selected from the group of devices consisting of:

batteries and flywheel.

8. The apparatus according to claim 1, further comprising a bypass switch coupling said AC line to said load.

9. The apparatus according to claim 8, wherein said bypass switch is a bi-directional thyristor.

10. The apparatus according to claim 1, further comprising a bypass switch coupling said variable speed energy source to said load.

11. The apparatus according to claim 10, wherein said bypass switch is a bi-directional thyristor.

13. The method according to claim 12, further comprising feeding the hybrid uninterruptible power supply with said energy storage module.

14. The method according to claim 13, wherein said feeding is derived from a load shed term.

15. The method according to claim 12, further comprising steps selected from at least one of the steps consisting of:

correcting for sag, correcting for surge, peak shaving, compensating for VAR, active filtering and elimination of active harmonics.

14-1. The method according to claim 12, further comprising charging said energy storage module while simultaneously providing output power to said load.

16. A hybrid variable speed generator/uninterruptible power supply device, comprising:

a variable speed generator producing differing amounts of power at different speeds; and

a hybrid uninterruptible power supply coupled in-line between an AC line and a load, wherein said hybrid uninterruptible power supply is switchably coupled to said variable speed generator, and wherein said hybrid uninterruptible power is comprised of a enhanced conduction angle dual boost DC regulator section coupled to an inverter with an energy storage module coupled therebetween.