US3863135A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Regulated Transformerless Power Supply
Assignee: International Business Machines Corp
•
Filing: 1973-07-16
•
Granted: 1975-01-28
•
Expires: 1993-07-16
Abstract
Abstract A transformerless direct current power supply having a regulated voltage output is disclosed. The supply uses cascaded sections of capacitive series voltage dividers in series to reduce and store full-wave recitifed DC input voltage which is then discharged in parallel at the desired output level. The charging and discharging of the cascaded capacitive series is regulated by a switching network driven by a feedback voltage derived from the output to regulate the charging of the capacitors in series and discharge of them in parallel.
Inventors
- 👤 Leon Warner Atwood
- 👤 Peruvemba Swam Balasubramanian
- 👤 John Brian Gillett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 14:33
CPC Classifications
H; H02; H02M; H02M3/00; H02M3/02; H02M3/04; H02M3/06; H02M3/07
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
319 words
A method for converting direct current power at an input voltage level to a lower controlled output voltage level at a load, comprising the steps of: switching said input voltage through a first switch of M controllable conductance switches to the first capacitive series voltage divider of a series of N capacitive series voltage dividers, said dividers being connected together from the divided voltage output of one of said dividers to the input of the next of said dividers in said series by similar such controllable conductance switches, and simultaneously switching said divided voltage outputs of the even numbered ones of said N dividers, where N is any whole number, to the next connected element by actuating the odd numbered ones of said M switches where M equals N+1; storing and reducing the voltage of an electrical charge in N capacitive series voltage dividers connected in said series via controllable conductance switches by operating said odd numbered switches to charge said series connected capacitive voltage dividers with power from the element next previous in the series with the last such switches connecting the Nth divider to a load; controlling the switching of said controllable conductance switches by a signal from a mutually exclusive switching control which operates all of said odd numbered switches simultaneously and all of said even numbered switches simultaneously, but at alternate times to insure that all of said even numbered switches are in opposed conductive condition to said odd numbered switches at all times; sensing the output voltage at the output of said Nth divider connected via said Mth controllable conductance switch to said load; comparing said output voltage with a desired reference voltage and generating a control signal proportional to the difference therebetween; and operating said mutually exclusive switching control in response to said control signal thereby providing a pulse width modulated control of said storing and reducing steps to regulate said output voltage.
Claim 2
Independent Claim
319 words
A method for converting direct current power at an input voltage level to a lower controlled output voltage level at a load, comprising the steps of: switching said input voltage through a first switch of M controllable conductance switches to the first capacitive series voltage divider of a series of N capacitive series voltage dividers, said dividers being connected together from the divided voltage output of one of said dividers to the input of the next of said dividers in said series by similar such controllable conductance switches, and simultaneously switching said divided voltage outputs of the even numbered ones of said N dividers, where N is any whole number, to the next connected element by actuating the odd numbered ones of said M switches where M equals N+1; storing and reducing the voltage of an electrical charge in N capacitive series voltage dividers connected in said series via controllable conductance switches by operating said odd numbered switches to charge said series connected capacitive voltage dividers with power from the element next previous in the series with the last such switches connecting the Nth divider to a load; controlling the switching of said controllable conductance switches by a signal from a mutually exclusive switching control which operates all of said odd numbered switches simultaneously and all of said even numbered switches simultaneously, but at alternate times to insure that all of said even numbered switches are in opposed conductive condition to said odd numbered switches at all times; sensing the output voltage at the output of said Nth divider connected via said Mth controllable conductance switch to said load; comparing said output voltage with a desired reference voltage and generating a control signal proportional to the difference therebetween; and operating said mutually exclusive switching control in response to said control signal thereby providing a pulse width modulated control of said storing and reducing steps to regulate said output voltage.
Claim 3
Dependent Claim
296 words
A power conversion circuit for converting direct current power at a higher source input voltage level to direct current power at a lower controlled output voltage level, comprising input terminals adapted to receive power from a full-wave rectified source and output terminals adapted to deliver said power at a lower controlled output voltage to a load; and further comprising: charge storage and voltage reduction means for storing and reducing voltage comprising at least one stage of series connected capacitors; input switching means of contrOllable conductance for controllably coupling said charge storage and voltage reducing means in series with said input terminals; output switching means of controllable conductance for controllably connecting said stage of charge storage and voltage reduction means in parallel with said output terminals; control means for alternately switching said input switching means and said output switching means in opposite conductive condition to one another, respectively; and means for sensing the voltage level at said output terminals; means for comparing said output voltage with a desired voltage level; and means responsive to the difference between said voltage levels resulting in said comparison step for operating said control means in a pulse width modulation mode, thereby controlling the amount of charge and the voltage delivered at said output terminals; and having a plurality of said charge storage and voltage reducing stages, each having the same voltage division capability and, after said at least one stage, being connectable from the reduced voltage output of one to the input of another by controllable conductance switches controlled by said control means to achieve an output voltage reduction of the function Xn where n is the last said stage number and is any whole integer and X is any whole number divisor embodied in said voltage reducing stages as desired.
Claim 4
Dependent Claim
296 words
A power conversion circuit for converting direct current power at a higher source input voltage level to direct current power at a lower controlled output voltage level, comprising input terminals adapted to receive power from a full-wave rectified source and output terminals adapted to deliver said power at a lower controlled output voltage to a load; and further comprising: charge storage and voltage reduction means for storing and reducing voltage comprising at least one stage of series connected capacitors; input switching means of contrOllable conductance for controllably coupling said charge storage and voltage reducing means in series with said input terminals; output switching means of controllable conductance for controllably connecting said stage of charge storage and voltage reduction means in parallel with said output terminals; control means for alternately switching said input switching means and said output switching means in opposite conductive condition to one another, respectively; and means for sensing the voltage level at said output terminals; means for comparing said output voltage with a desired voltage level; and means responsive to the difference between said voltage levels resulting in said comparison step for operating said control means in a pulse width modulation mode, thereby controlling the amount of charge and the voltage delivered at said output terminals; and having a plurality of said charge storage and voltage reducing stages, each having the same voltage division capability and, after said at least one stage, being connectable from the reduced voltage output of one to the input of another by controllable conductance switches controlled by said control means to achieve an output voltage reduction of the function Xn where n is the last said stage number and is any whole integer and X is any whole number divisor embodied in said voltage reducing stages as desired.
Claim 5
Dependent Claim
21 words
A power conversion circuit as described in claim 2, further comprising: means for providing an output voltage at each said stage.
References Cited (Backward Citations)
US2663806A
Cited
US3478258A
Cited
US3543130A
Cited
US3497792A
Cited
US3505586A
Cited
US3621362A
Cited
US3602795A
Cited
US3708742A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-27 | 1978-07-29 | 1979-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-27 | 1982-07-29 | 1983-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-27 | 1986-07-29 | 1987-01-28 | $7700.00 | Window Closed / Lapsed |