US6031737A
Expired / Lapsed
US
⏱️ 0.0 years remaining
AC-DC power supply
Assignee: Aquagas New Zealand Ltd
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Filing: 1996-10-24
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Granted: 2000-02-29
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Expires: 2016-10-24
Abstract
Abstract An AC-DC power supply system for receiving a three phase mains supply and outputting a transformed DC supply. The power supply unit has a rectifier circuit (30) providing an output to a three phase inverter circuit (40) to generate a pseudo AC three phase output of higher frequency than the AC supplied to the rectifier circuit (30). A three phase transformer (60) receives the pseudo AC three phase output and transforms the output to a three phase rectifier circuit (70) to generate the output DC supply. The inverter circuit (40) provides a three leg bridge structure with each leg having a switching device one of which is used to provide a phase reference whereas the other two legs control the relative phase shift on each leg to reduce the phase shift relative to the phase reference on one leg and increase the phase shift relative to the phase reference on the other leg.
Inventors
- 👤 Andrew William Green
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:31
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/02; H02M7/04; H02M7/12; H02M7/21; H02M7/217; H02M3/00; H02M3/01; H02M3/22; H02M3/24; H02M3/28; H02M3/325; H02M3/335; H02M3/33569; H02M3/33573; H02M7/42; H02M7/44; H02M7/48; H02M7/4807; Y; Y02; Y02B; Y02B70/00; Y02B70/10
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
185 words
An AC-DC power supply comprising: a three phase rectifier circuit generating a first rectified output in response to an input voltage having an input voltage frequency; a controlled three phase inverter circuit receiving the first rectified output and generating a pseudo-AC three phase output having a frequency higher than the frequency of the three phase AC supply supplied to the rectifier circuit, wherein the pseudo-AC three phase output is controlled by means of phase shifting; a three phase transformer receiving said phase shift controlled pseudo-AC three phase output; and a second three phase rectifier circuit receiving the transformed pseudo-AC three phase output from said transformer and generating the output DC supply, wherein said three phase transformer comprises: three secondaries each formed from a conductive tube, said conductive tubes being substantially parallel and electrically connected at first end thereof; three transformer cores, each corresponding to a phase, each in the form of a cylindrical member threaded onto a corresponding said conductive tube; and three primary windings each corresponding to a phase, wound so as to pass through the interiors of adjacent pairs of said conductive tubes.
Claim 2
Dependent Claim
185 words
An AC-DC power supply comprising: a three phase rectifier circuit generating a first rectified output in response to an input voltage having an input voltage frequency; a controlled three phase inverter circuit receiving the first rectified output and generating a pseudo-AC three phase output having a frequency higher than the frequency of the three phase AC supply supplied to the rectifier circuit, wherein the pseudo-AC three phase output is controlled by means of phase shifting; a three phase transformer receiving said phase shift controlled pseudo-AC three phase output; and a second three phase rectifier circuit receiving the transformed pseudo-AC three phase output from said transformer and generating the output DC supply, wherein said three phase transformer comprises: three secondaries each formed from a conductive tube, said conductive tubes being substantially parallel and electrically connected at first end thereof; three transformer cores, each corresponding to a phase, each in the form of a cylindrical member threaded onto a corresponding said conductive tube; and three primary windings each corresponding to a phase, wound so as to pass through the interiors of adjacent pairs of said conductive tubes.
Claim 3
Dependent Claim
40 words
An AC-DC power supply as claimed in claim 1 wherein each said transformer core in the form of a cylindrical member formed from a plurality of ferrite discs, each disc having an aperture therein adapted to accommodate a corresponding cylinder.
Claim 4
Dependent Claim
23 words
An AC-DC power supply as claimed in claim 1 wherein said controlled three phase inverter circuit further includes a plurality of switching devices.
Claim 5
Dependent Claim
25 words
An AC-DC power supply as claimed in claim 1 wherein said controlled three phase inverter circuit includes switching devices in the form of power transistors.
Claim 6
Dependent Claim
26 words
An AC-DC power supply as claimed in claim 1 wherein said frequency of said pseudo-AC three phase output is substantially higher than the input voltage frequency.
Claim 7
Dependent Claim
34 words
An AC-DC power supply as claimed in claim 1 wherein said frequency of said pseudo-AC three phase output is greater than or equal to one order of magnitude higher than the input voltage frequency.
Claim 8
Dependent Claim
31 words
An AC-DC power supply as claimed in claim 1 wherein said pseudo-AC three phase output is greater than or equal to two orders of magnitude higher than the input voltage frequency.
Claim 9
Dependent Claim
80 words
A controllable three phase inverter circuit receiving a DC supply to produce a three phase pseudo AC output supply wherein the inverter comprises: a three leg bridge structure; each leg of said bridge structure comprising at least one controllable switching device; at least one switching device of one of said legs forming a phase reference; and wherein the voltage of the inverter circuit is controlled by means of phase shifting the relative phases of each signal carried by each leg.
Claim 10
Dependent Claim
80 words
A controllable three phase inverter circuit receiving a DC supply to produce a three phase pseudo AC output supply wherein the inverter comprises: a three leg bridge structure; each leg of said bridge structure comprising at least one controllable switching device; at least one switching device of one of said legs forming a phase reference; and wherein the voltage of the inverter circuit is controlled by means of phase shifting the relative phases of each signal carried by each leg.
Claim 11
Dependent Claim
87 words
A controllable three phase inverter circuit as claimed in claim 8 wherein the phase modulation is effected by said at least one switching device of one of the other two legs having the relative phase shift controlled with respect to the phase reference; and said at least one switching device of the third leg having the relative phase shift controlled with respect to the phase reference to increase the phase shift relative to the phase reference and thereby controlling the output voltage level of the inverter circuit.
Claim 12
Dependent Claim
120 words
A soft-switching three phase inverter circuit receiving a DC input supply and generating a pseudo AC three phase output supply wherein said inverter circuit comprises: at least two switching devices per phase; each said switching device having a capacitive element connected in parallel across it and each phase of the output supply including an inductive element; a respective capacitive element and inductive element of each phase forming an LC resonant circuit; and wherein the turn-off of each said switching element is controlled to have a deadtime between switching phases during which time said LC resonant circuit causes the next sequential switching element that is to be turned on to have substantially zero voltage across it at the time of switching.
Claim 13
Dependent Claim
120 words
A soft-switching three phase inverter circuit receiving a DC input supply and generating a pseudo AC three phase output supply wherein said inverter circuit comprises: at least two switching devices per phase; each said switching device having a capacitive element connected in parallel across it and each phase of the output supply including an inductive element; a respective capacitive element and inductive element of each phase forming an LC resonant circuit; and wherein the turn-off of each said switching element is controlled to have a deadtime between switching phases during which time said LC resonant circuit causes the next sequential switching element that is to be turned on to have substantially zero voltage across it at the time of switching.
Claim 14
Independent Claim
80 words
A method for controlling the output voltage of a three phase inverter circuit comprising the steps of: assigning a first phase as a phase reference; controlling the relative phase shift of one of the other two phases so that the phase difference between the first place and the one of the other two is reduced; and controlling the relative phase shift of the third phase so that the phase difference between the third phase and the first phase is increased.
Claim 15
Independent Claim
80 words
A method for controlling the output voltage of a three phase inverter circuit comprising the steps of: assigning a first phase as a phase reference; controlling the relative phase shift of one of the other two phases so that the phase difference between the first place and the one of the other two is reduced; and controlling the relative phase shift of the third phase so that the phase difference between the third phase and the first phase is increased.
Claim 16
Independent Claim
208 words
An apparatus for the electrolysis of water to liberate hydrogen and oxygen gas, the apparatus comprising: a cell unit having at least one cathode/anode electrode pair; and an AC-DC power supply comprising: a three phase rectifier circuit generating a first rectified output in response to an input voltage; a controlled three phase inverter circuit receiving the first rectified output and generating a pseudo three phase output having a frequency higher than the frequency of the three phase AC supply supplied to said rectifier circuit, wherein the pseudo-AC three phase output is controlled by means of phase shifting; a three phase transformer receiving the phase shift controlled pseudo-AC three phase output; and a second three phase rectifier circuit receiving the transformed pseudo-AC three phase output from said transformer and generating the output DC supply, wherein said three phase transformer comprises: three secondaries each formed from a conductive tube, said conductive tubes being substantially parallel and electrically connected at a first end thereof; three transformer cores, each corresponding to a phase, each in the form of a cylindrical member threaded onto a corresponding said conductive tube; and three primary windings each corresponding to a phase, wound so as to pass through the interiors of adjacent pairs of said conductive tubes.
Claim 17
Independent Claim
208 words
An apparatus for the electrolysis of water to liberate hydrogen and oxygen gas, the apparatus comprising: a cell unit having at least one cathode/anode electrode pair; and an AC-DC power supply comprising: a three phase rectifier circuit generating a first rectified output in response to an input voltage; a controlled three phase inverter circuit receiving the first rectified output and generating a pseudo three phase output having a frequency higher than the frequency of the three phase AC supply supplied to said rectifier circuit, wherein the pseudo-AC three phase output is controlled by means of phase shifting; a three phase transformer receiving the phase shift controlled pseudo-AC three phase output; and a second three phase rectifier circuit receiving the transformed pseudo-AC three phase output from said transformer and generating the output DC supply, wherein said three phase transformer comprises: three secondaries each formed from a conductive tube, said conductive tubes being substantially parallel and electrically connected at a first end thereof; three transformer cores, each corresponding to a phase, each in the form of a cylindrical member threaded onto a corresponding said conductive tube; and three primary windings each corresponding to a phase, wound so as to pass through the interiors of adjacent pairs of said conductive tubes.
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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) | 2003-02-28 | 2003-08-30 | 2004-02-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-02-28 | 2007-08-30 | 2008-02-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-02-28 | 2011-08-30 | 2012-02-29 | $7700.00 | Window Closed / Lapsed |