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US5457374A Expired / Lapsed US ⏱️ 0.0 years remaining

Motor controller for operating an inverter in current-controlled and voltage-controlled modes

Assignee: Honeywell International Inc
•
Filing: 1993-08-24
•
Granted: 1995-10-10
•
Expires: 2013-08-24
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Abstract

Abstract A motor controller for brushless motors operates an inverter in a current-controlled mode for low motor speeds and in a voltage-controlled mode for high motor speeds. By switching from the current-controlled mode to the voltage-controlled mode at higher speeds, the motor can be designed at maximum efficiency, and minimum weight, cost and volume.

Inventors

  • 👤 Brian T. Branecky
  • 👤 Edward L. Johnson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 20:32
CPC Classifications
H; H02; H02P; H02P6/00; H02P6/08; H02P6/28

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 138 words
A system comprising: a brushless electric motor having a rotor and a stator; inverter means for commutating power to said motor which is synchronous with the motor; position feedback means for providing at least one feedback signal indicating the position of said rotor relative to said stator; first motor controller means, responsive to said at least one feedback signal, for generating first commutation commands corresponding to a current-controlled mode of operation; second motor controller means, responsive to said at least one feedback signal, for generating second commutation commands corresponding to a voltage-controlled mode of operation; and selecting means, responsive to said first and second motor controller means, for supplying said first commutation commands when motor speed is below a threshold and supplying said second commutation commands when said motor speed is above said threshold to said inverter means.
Claim 2
Independent Claim 138 words
A system comprising: a brushless electric motor having a rotor and a stator; inverter means for commutating power to said motor which is synchronous with the motor; position feedback means for providing at least one feedback signal indicating the position of said rotor relative to said stator; first motor controller means, responsive to said at least one feedback signal, for generating first commutation commands corresponding to a current-controlled mode of operation; second motor controller means, responsive to said at least one feedback signal, for generating second commutation commands corresponding to a voltage-controlled mode of operation; and selecting means, responsive to said first and second motor controller means, for supplying said first commutation commands when motor speed is below a threshold and supplying said second commutation commands when said motor speed is above said threshold to said inverter means.
Claim 3
Dependent Claim 36 words
The system of claim 1, wherein said position feedback means includes position sensor means for providing position signals indicating said rotor position, and back emf means for generating emf signals indicating back emf of said motor.
Claim 4
Dependent Claim 24 words
The system of claim 2, wherein said back emf means includes no-load generator means, mechanically coupled to said motor for generating said emf signals.
Claim 5
Dependent Claim 16 words
The system of claim 1, wherein said threshold is approximately 50% of maximum rated motor speed.
Claim 6
Dependent Claim 15 words
The system of claim 1, wherein said first and second controllers are digital motor controllers.
Claim 7
Dependent Claim 25 words
The system of claim 5, wherein said first and second motor controller means includes first and second microprocessors for generating first and second commutation commands.
Claim 8
Dependent Claim 15 words
The system of claim 1, wherein said first and second controllers are analog motor controllers.
Claim 9
Dependent Claim 13 words
The system of claim 1, wherein said motor has a relatively high inductance.

References Cited (Backward Citations)

US4037144A Cited
US4315203A Cited
US4879502A Cited
US5166585A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-10-09 1999-04-10 1999-10-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-10-09 2003-04-10 2003-10-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-10-09 2007-04-10 2007-10-10 $7700.00 Window Closed / Lapsed

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