US3815003A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combined switch and chopper for supplying an a.c. motor
Assignee: Jeumont Schneider SA
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Filing: 1972-11-10
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Granted: 1974-06-04
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Expires: 1992-11-10
Abstract
Abstract A combined switch and chopper for supplying an a.c. motor with regenerative braking. The switch and chopper are characterised in that they comprise: a first set of routing thyristors whose anodes are connected to the positive side of a d.c. supply via a choke and the main thyristor of a first chopper and whose cathodes are connected to the motor terminals; a second set of routing thyristors whose cathodes are connected to the negative side of the supply via a second choke and the main thyristor of a second chopper and whose anodes are connected to the motor terminals; two thyristors for shunting the chokes; a first group of diodes whose cathodes are connected to the motor terminals and whose anodes are connected to a common point; a second group of diodes whose anodes are connected to the motor terminals and whose cathodes are connected to a common point; two switching thyristors connected in series between the common points, such thyristors being in antiparallel with the two diode groups; means for switching the thyristors comprising more particularly an auxiliary circuit for cyclically and alternately switching each routing thyristor set by way of the corresponding switching thyristor and corresponding diode group; two free wheel circuits helping to hold the motor current during periodic interruptions of the motor power supply; and a recovery circuit for braking the motor when the same is generating.
Inventors
- 👤 A Wiart
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 01:43
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/505; H02M7/515; H02M7/5152; H02M5/00; H02M5/02; H02M5/04; H02M5/22; H02M5/25; H02M5/27
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
226 words
A combined switch and chopper foR supplying an a.c. motor with regenerative braking, characterised in that it comprises: a first set of routing thyristors whose anodes are connected to the positive side of a d.c. supply via a choke and the main thyristor of a first chopper and whose cathodes are connected to the motor terminals; a second set of routing thyristors whose cathodes are connected to the negative side of the supply via a second choke and the main thyristor of a second chopper and whose anodes are connected to the motor terminals; two thyristors for shunting the chokes; a first group of diodes whose cathodes are connected to the motor terminals and whose anodes are connected to a common point; a second group of diodes whose anodes are connected to the motor terminals and whose cathodes are connected to a common point; two switching thyristors connected in series between the common points, such thyristors being in antiparallel with the two diode groups; means for switching the thyristors comprising more particularly an auxiliary circuit for cyclically and alternately switching each routing thyristor set by way of the corresponding switching thyristor and corresponding diode group; two free wheel circuits helping to hold the motor current during periodic interruptions of the motor power supply; and a recovery circuit for braking the motor when the same is generating.
Claim 2
Dependent Claim
226 words
A combined switch and chopper foR supplying an a.c. motor with regenerative braking, characterised in that it comprises: a first set of routing thyristors whose anodes are connected to the positive side of a d.c. supply via a choke and the main thyristor of a first chopper and whose cathodes are connected to the motor terminals; a second set of routing thyristors whose cathodes are connected to the negative side of the supply via a second choke and the main thyristor of a second chopper and whose anodes are connected to the motor terminals; two thyristors for shunting the chokes; a first group of diodes whose cathodes are connected to the motor terminals and whose anodes are connected to a common point; a second group of diodes whose anodes are connected to the motor terminals and whose cathodes are connected to a common point; two switching thyristors connected in series between the common points, such thyristors being in antiparallel with the two diode groups; means for switching the thyristors comprising more particularly an auxiliary circuit for cyclically and alternately switching each routing thyristor set by way of the corresponding switching thyristor and corresponding diode group; two free wheel circuits helping to hold the motor current during periodic interruptions of the motor power supply; and a recovery circuit for braking the motor when the same is generating.
Claim 3
Dependent Claim
142 words
A combined switch and chopper according to claim 1 wherein the auxiliary circuit comprises: a transformer whose secondary winding is connected between the anode-cathode junction of the two switching thyristors and the anode-cathode junction of two auxiliary diodes connected in series and connected in anti-parallel between the poles of the power supply, the transformer primary winding being connected between the centre points of two bridges disposed in parallel to the supply terminals, viz a first bridge comprising two capacitors in series, and a second bridge of two serially connected auxiliary thyristors arranged the opposite way round to the auxiliary diodes; and a means for simultaneously turning-on one of the auxiliary thyristors to discharge the capacitor bridge via the transformer primary, the switching thyristor allowing current to flow from the transformer secondary through one of the auxiliary diodes to the corresponding diode group.
Claim 4
Dependent Claim
129 words
A switch and chopper according to claim 1 wherein the auxiliary circuit comprises: a bridge of two serially connected auxiliary thyristors in parallel with the routing thyristors; two serially connected first auxiliary diodes disposed between, and the same way around as, the two switching thyristors; a capacitor connected between the centre point of the auxiliary thyristor bridge and the series connection between the two diodes; two other auxiliary diodes, one having its anode connected to the negative side of the supply and its cathode connected to the anode of the switching thyristor associated with the first chopper, the other of the two other auxiliary diodes being connected symmetrically in relation to the first such diode; and means for turning-on the auxiliary thyristors seriatim simultaneously with the corresponding switching thyristor.
Claim 5
Dependent Claim
99 words
A switch and chopper according to claim 1 but in which the switching thyristors have no provision for being connected in series and the auxiliary circuit comprises: a transformer having two secondary windings, the anodes of the first routing thyristor set being connected to the anode of the corresponding switching thyristor by way of one of such secondary windings, the other winding being connected, in symmetrical relation to the first winding, with the other switching thyristor, and means for so cylically energizing the primary winding of such transformer as to produce an auxiliary voltage for switching the routing thyristors.
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) | 1977-06-03 | 1977-12-03 | 1978-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-03 | 1981-12-03 | 1982-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-03 | 1985-12-03 | 1986-06-04 | $7700.00 | Window Closed / Lapsed |