US5043857A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Real-time control of PWM inverters by pattern development from stored constants
Assignee: Sundstrand Corp
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Filing: 1990-04-11
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Granted: 1991-08-27
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Expires: 2010-04-11
Abstract
Abstract In a real time control of a pulse width modulated inverter, equations are developed relating switching angle, system parameter or parameters and output harmonics. Constants are stored which define a preferred angle for each switching event. Switching angles are calculated in real time by solving the equation in accordance with the value of the system parameter.
Inventors
- 👤 Maurice A. Kirchberg, Jr.
- 👤 Alexander Cook
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 08:41
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/53; H02M7/537; H02M7/539; H02M7/5395; H02M1/00; H02M1/0003; H02M1/0016; H02M1/0022
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
96 words
In a pulse width modulated inverter, a system for generating a switching angle control signal in response to an inverter output parameter, comprising in combination; means for storing a set of constants for a switching angle, said constants comprising constant terms of an equation which describes a locus of values of said switching angle for a desired inverter output characteristic as a function of said parameter; means for fetching said stored set of constants and calculating said switching angle as a solution to said equation with said constants and said parameter comprising terms of said equation.
Claim 2
Dependent Claim
96 words
In a pulse width modulated inverter, a system for generating a switching angle control signal in response to an inverter output parameter, comprising in combination; means for storing a set of constants for a switching angle, said constants comprising constant terms of an equation which describes a locus of values of said switching angle for a desired inverter output characteristic as a function of said parameter; means for fetching said stored set of constants and calculating said switching angle as a solution to said equation with said constants and said parameter comprising terms of said equation.
Claim 3
Dependent Claim
19 words
A pulse width modulated inverter as in claim 1 wherein said desired inverter output characteristic is reduced harmonic distortion.
Claim 4
Dependent Claim
114 words
In a pulse width modulated invertor, a system for generating a switching angle control signal in response to an invertor output parameter, comprising in combination; means for storing a plurality of sets of constants for a plurality of said switching angles, each of said sets of constants comprising constant terms of an equation which describes a locus of values of one of said plurality of switching angles for a desired inverter output characteristic as a function of said parameter; means for fetching said stored plurality of sets of constants and calculating a plurality of said switching angles as a solution to said equation with said constants and said parameter comprising terms of said equation.
Claim 5
Dependent Claim
114 words
In a pulse width modulated invertor, a system for generating a switching angle control signal in response to an invertor output parameter, comprising in combination; means for storing a plurality of sets of constants for a plurality of said switching angles, each of said sets of constants comprising constant terms of an equation which describes a locus of values of one of said plurality of switching angles for a desired inverter output characteristic as a function of said parameter; means for fetching said stored plurality of sets of constants and calculating a plurality of said switching angles as a solution to said equation with said constants and said parameter comprising terms of said equation.
Claim 6
Dependent Claim
19 words
A pulse width modulated inverter as in claim 3 wherein said desired inverter output characteristic is reduced harmonic distortion.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-08-26 | 1995-02-25 | 1995-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-08-26 | 1999-02-25 | 1999-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-08-26 | 2003-02-25 | 2003-08-27 | $7700.00 | Window Closed / Lapsed |