US4020411A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Static power converter controlling apparatus for reducing noise generated by phase shift control
Assignee: Hitachi Ltd
•
Filing: 1975-02-21
•
Granted: 1977-04-26
•
Expires: 1995-02-21
Abstract
Abstract A static power converter includes a plurality of thyristor bridges. The level of the control voltage is measured and a signal representative of the measured level is generated which causes one thyristor bridge to maintain a substantially zero output D.C. voltage, while another thyristor bridge operates with phase shift control.
Inventors
- 👤 Takashi Tsuboi
- 👤 Kyozo Tachibana
- 👤 Kaoru Tamura
- 👤 Fujimaro Imaizumi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 12:53
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/02; H02M7/04; H02M7/12; H02M7/145; H02M7/155; H02M7/19; H02M7/162
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
138 words
In a static power converter comprising a transformer having a number of separate secondary coils, a converter assembly driven to its full output and consisting of a number of thyristor bridges for the bilateral conversion of A. C. power into D. C. power and vice versa, each of which is connected to one of these secondary coils and all of which are connected in series configuration on the D. C. side, the improvement comprising a device for the phase shift control of the thyristor bridges in dependence on a control voltage, the level of this control voltage being detected by a level detector and a signal generated in accordance with said level by means of which the output D. C. voltage of one thyristor bridge is maintained at zero, whereas another thyristor bridge operates with phase shift control.
Claim 2
Dependent Claim
138 words
In a static power converter comprising a transformer having a number of separate secondary coils, a converter assembly driven to its full output and consisting of a number of thyristor bridges for the bilateral conversion of A. C. power into D. C. power and vice versa, each of which is connected to one of these secondary coils and all of which are connected in series configuration on the D. C. side, the improvement comprising a device for the phase shift control of the thyristor bridges in dependence on a control voltage, the level of this control voltage being detected by a level detector and a signal generated in accordance with said level by means of which the output D. C. voltage of one thyristor bridge is maintained at zero, whereas another thyristor bridge operates with phase shift control.
Claim 3
Dependent Claim
176 words
In a static power converter comprising a transformer having a number of separate secondary coils, a converter assembly driven to its full output and consisting of a number of thyristor bridges for the bilateral conversion of A. C. power into D. C. power and vice versa, each of which is connected to one of these secondary coils and all of which are connected in series configuration on the D. C. side, the improvement comprising a device for the phase shift control of the thyristor bridges in dependence on a control voltage, the level of this control voltage being detected by a level detector and a signal generated in accordance with said level by means of which the output D. C. voltage of one thyristor bridge is maintained at a small value no greater than the voltage drop across a conducting thyristor bridge whereas another thyristor bridge operates with phase shift control, characterized in that one thyristor bridge is connected to the secondary coil of the transformer by means of a switch controlled by the level detector.
Claim 4
Dependent Claim
176 words
In a static power converter comprising a transformer having a number of separate secondary coils, a converter assembly driven to its full output and consisting of a number of thyristor bridges for the bilateral conversion of A. C. power into D. C. power and vice versa, each of which is connected to one of these secondary coils and all of which are connected in series configuration on the D. C. side, the improvement comprising a device for the phase shift control of the thyristor bridges in dependence on a control voltage, the level of this control voltage being detected by a level detector and a signal generated in accordance with said level by means of which the output D. C. voltage of one thyristor bridge is maintained at a small value no greater than the voltage drop across a conducting thyristor bridge whereas another thyristor bridge operates with phase shift control, characterized in that one thyristor bridge is connected to the secondary coil of the transformer by means of a switch controlled by the level detector.
Claim 5
Dependent Claim
29 words
An improved static power converter according to claim 1, characterized in that a switch, controlled by the level detector, is connected in parallel with one of the thyristor bridges.
Claim 6
Dependent Claim
43 words
An improved static power converter according to claim 1, wherein the phase shift device and level detector provide for the reduction of the level of harmonic components produced by the bilateral conversion of A. C. power into D. C. power and vice versa.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-04-25 | 1980-10-25 | 1981-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-04-25 | 1984-10-25 | 1985-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-04-25 | 1988-10-25 | 1989-04-26 | $7700.00 | Window Closed / Lapsed |