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US4835408A Expired / Lapsed US ⏱️ 0.0 years remaining

Power conversion circuit

Assignee: NORMAND ELECTRICAL Ltd WEST HOUSE KING CROSS ROAD
•
Filing: 1982-08-31
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Granted: 1989-05-30
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Expires: 2002-08-31
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Abstract

Abstract A multi-phase switched reluctance motor is driven from a tow-point d.v. supply (11) in which capacitors (12) and (13) are provided across the supply with their common point (14) constituting a third power supply point. The load windings W 1 , W 3 , W 5 and W 2 , W 4 , W 6 are connected in two different load circuits connected across the different capacitors. In order to prevent the voltage of the third point wandering because the currents in the the two load circuits are not the same, control means (21) can control the distribution of current between the various load windings by appropriate control of semi-conductor switches in the various load circuits.

Inventors

  • 👤 William F. Ray
  • 👤 Rex M. Davis

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 02:01
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/505; H02M7/515; H02M7/525; H02M7/5152; H02M7/5155; H02P; H02P25/00; H02P25/02; H02P25/08; H02P25/092; H02P25/0925; H02M7/4811

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 150 words
A power conversion circuit comprising: a direct voltage source having two capacitors connected in series, with each other across the source to define a common point, two load circuits each comprising one or more loads, the loads in one load circuit being connected to the common point of the capacitors and to one side of the direct voltage source through individual controlled semi-conductor switches, and the loads in the other load circuit being connected between the said common point and the other side of the direct voltage source through individual controlled semi-conductor switches, and all of the loads being directly connected to the said common point, the power conversion circuit involving means responsive to the potential of the said common point, and control means for controlling the semi-conductor switches in accordance with the responsive means, to tend to maintain the potential of the said common point at a desired value.
Claim 2
Dependent Claim 150 words
A power conversion circuit comprising: a direct voltage source having two capacitors connected in series, with each other across the source to define a common point, two load circuits each comprising one or more loads, the loads in one load circuit being connected to the common point of the capacitors and to one side of the direct voltage source through individual controlled semi-conductor switches, and the loads in the other load circuit being connected between the said common point and the other side of the direct voltage source through individual controlled semi-conductor switches, and all of the loads being directly connected to the said common point, the power conversion circuit involving means responsive to the potential of the said common point, and control means for controlling the semi-conductor switches in accordance with the responsive means, to tend to maintain the potential of the said common point at a desired value.
Claim 3
Dependent Claim 29 words
A circuit as claimed in claim 1 including means responsive to the current in each of one or more loads arranged to control the semi-conductor switch for that load.
Claim 4
Dependent Claim 29 words
A circuit as claimed in claim 2 in which the switches are controlled to maintain the currents in the loads between respective set levels, which levels may be adjusted.
Claim 5
Dependent Claim 30 words
A circuit as claimed in claim 2 including means arranged to render the semi-conductor switches conducting at respective controllable frequencies and to render them non-conducting at certain controllable current levels.
Claim 6
Dependent Claim 26 words
A circuit as claimed in claim 1 including circuits including semi-conductor devices enabling each load to return energy to one or other of the said capacitors.
Claim 7
Dependent Claim 43 words
A circuit as claimed in claim 1 in which the control means is arranged in response to any difference between the potential of the said common point and a reference potential to control the semi-conductor switches to tend to reduce the said difference.
Claim 8
Dependent Claim 49 words
A circuit as claimed in claims 1 or 6 including two separate means, each responsive to the total current in one of the load circuits, the control means being arranged to control the semi-conductor switches to tend to cause the outputs of the two separate means to be equal.
Claim 9
Dependent Claim 37 words
A circuit as claimed in claim 7 in which each of the two separate means comprises a magnetic core linking its load circuit and means for delivering an output dependent upon the flux density in the core.
Claim 10
Dependent Claim 37 words
A circuit as claimed in claim 8 including on each core a bias winding arranged to produce a bias flux dependent upon the different in potential between the said common point and one side of the source.
Claim 11
Dependent Claim 37 words
A circuit as claimed in claim 1 in which the control means is arranged to control the semi-conductor switches to set the current in one load at a value corresponding to the power requirement of that load.
Claim 12
Dependent Claim 46 words
A circuit as claimed claims 1 or 10 in which the control means is arranged to control the instants of firing and commutating the semi-conductor switches so that the number of rises and falls of current per second in the two load circuits are the same.
Claim 13
Dependent Claim 66 words
A circuit as claimed in claim 1 including two separate means, each responsive to the total current in one of the load circuits, the control means being arranged in response to the outputs of the said separate means to control the semi-conductor switches to tend to cause the average total current in both load circuits together to correspond to the total power requirement of the load.
Claim 14
Dependent Claim 66 words
A circuit as claimed in claim 7 including two separate means, each responsive to the total current in one of the load circuits, the control means being arranged in response to the outputs of the said separate means to control the semi-conductor switches to tend to cause the average total current in both load circuits together to correspond to the total power requirement of the load.

References Cited (Backward Citations)

US3743924A Cited
US3935528A Cited
US4092509A Cited
US4136382A Cited
US4255783A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-05-29 1992-11-28 1993-05-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-05-29 1996-11-28 1997-05-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-05-29 2000-11-28 2001-05-30 $7700.00 Window Closed / Lapsed

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