Transient energy systems and methods for use of the same

• US 7,400,052 B1
• Filed: 11/29/2006
• Issued: 07/15/2008
• Est. Priority Date: 11/29/2006
• Status: Expired due to Fees

• Current Assignee: Piller USA, Inc. (Langley Holdings PLC)
• Original Assignee: Active Power Incorporated
• Inventors: Badger, David A.
• Primary Examiner(s): Ponomarenko; Nicholas
• Application Number:
  US11/606,867
• Time in Patent Office: 594 Days
• Field of Search: 290/1.A, 290/52, 290/5, 290/4.B, 322/4, 322/7
• US Class Current: 290/1.00A
• CPC Class Codes: H02J 15/007 involving storage in the form of mechanical energy, e.g. fly-wheels
• CPC Class Codes: H02K 7/025 for power storage
• CPC Class Codes: H02P 23/08 Controlling based on slip frequency, e.g. adding slip frequency and speed proportional frequency
• CPC Class Codes: H02P 9/46 Control of asynchronous generator by variation of capacitor
• CPC Class Codes: Y02E 60/16 Mechanical energy storage, e.g. flywheels or pressurised fluids

Abstract

This disclosure relates to transient energy systems for supplying power to a load substantially instantaneously on demand. Transient energy systems may include a flywheel coupled the rotor of an induction motor generator. One embodiment of the disclosure refers to systems and methods for reducing loads on a bearing in a transient energy system. In another embodiment, the disclosure refers to an induction motor generator that is optimized for high power transient power generation, yet low power motor operation. Yet another embodiment of the disclosure refers to using a flywheel as a drag pump to cool components of a transient energy system. In yet another embodiment, a slip control scheme is discussed for regulating a DC bus. In yet a further embodiment of the disclosure a method is provided for reducing unnecessary turbine starts by making turbine start a function of the rotational velocity of a flywheel.

Claims

1. A method for regulating DC bus voltage in a system comprising a DC bus and flywheel energy storage device including an induction motor/generator, the method comprising:

providing a slip demand based on a measured DC bus voltage;

generating first and second induction motor/generator control parameters based on the slip demand;

providing a signal having a frequency and a phase angle based on the first and second control parameters, wherein the second control parameter adjusts the phase angle in proportion to the slip demand; and

applying the signal to the induction motor/generator.

2. The method of claim 1, further comprising:

converting the signal into a sinusoidal signal.

3. The method of claim 1, further comprising:

changing the electric frequency in response to a change in the measured DC bus voltage.

4. The method of claim 1, further comprising:

receiving a mechanical speed frequency of the induction motor generator;

determining the frequency based on the mechanical speed frequency and the slip demand; and

integrating the frequency to provide the first parameter, the first parameter comprising the signal having the frequency and an unadjusted phase angle.

5. The method of claim 1, further comprising:

scaling the slip demand to provide the second parameter.

6. The method of claim 1, wherein applying the signal comprises regulating the DC bus voltage.