US3629615A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Current-limiting means for dc pulse-controlled circuits
Assignee: TECH/OPS Inc
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Filing: 1968-06-11
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Granted: 1971-12-21
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Expires: 1988-06-11
Abstract
Abstract A static switching controller for repetitively connecting to, and disconnecting from, a load of a DC source, the circuit of the load of the source possessing inductance, comprises thyristor means, energizable to connect the load of the source, and a commutating capacitor for switching off the thyristor means, wherein there are provided sensing means which senses a voltage dependent upon the current passing through the thyristor means on commutation thereof and circuit elements which, when said voltage sensed by the sensing means exceeds a predetermined value, are operative to effect limitation of the main current flowing through the load by reducing the ratio of conducting to nonconducting time of the thyristor means.
Inventors
- 👤 David Gurwicz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:41
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/08; H03K17/082; H03K17/0824; H02; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/29; H03K17/51; H03K17/56; H03K17/72; H03K17/73; H03K3/00; H03K3/02; H03K3/35; H03K3/351; Y; Y10; Y10S; Y10S388/00; Y10S388/90; Y10S388/903; Y10S388/907; Y10S388/917; Y10S388/918; Y10S388/919
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
176 words
A static switching controller for effecting repetitive connection and disconnection between a load and a DC source, said load being coupled to said source partially by means of leads, said load and source possessing inductance, said controller comprising: thyristor means, coupled between said source and load for providing a path for the flow of current between said source and load when said thyristor means is rendered conducting, the periods of conduction of the thyristor means determining the mean current through said load, a commutating capacitor coupled to said thyristor means for reverse-biasing said thyristor means whereby it is switched to a nonconducting state, said capacitor being charged in a first direction by said source, sensing means coupled to said thyristor means for sensing a voltage dependent upon the current passing through the thyristor means on commutation thereof, and control circuit means, responsive to said sensed voltage when said sensed voltage exceeds a predetermined value, for reducing the conducting to nonconducting time of the thyristor means to effect limitation of the mean current flowing through the load.
Claim 2
Dependent Claim
176 words
A static switching controller for effecting repetitive connection and disconnection between a load and a DC source, said load being coupled to said source partially by means of leads, said load and source possessing inductance, said controller comprising: thyristor means, coupled between said source and load for providing a path for the flow of current between said source and load when said thyristor means is rendered conducting, the periods of conduction of the thyristor means determining the mean current through said load, a commutating capacitor coupled to said thyristor means for reverse-biasing said thyristor means whereby it is switched to a nonconducting state, said capacitor being charged in a first direction by said source, sensing means coupled to said thyristor means for sensing a voltage dependent upon the current passing through the thyristor means on commutation thereof, and control circuit means, responsive to said sensed voltage when said sensed voltage exceeds a predetermined value, for reducing the conducting to nonconducting time of the thyristor means to effect limitation of the mean current flowing through the load.
Claim 3
Dependent Claim
37 words
A controller as claimed in claim 1, wherein the sensing means are adapted to sense a transient voltage in the circuit of the load, the DC source and the thyristor means on commutation of the thyristor means.
Claim 4
Dependent Claim
31 words
A controller as claimed in claim 1, wherein the sensing means are adapted to sense the transient voltage at the anode of the thyristor means on commutation of the thyristor means.
Claim 5
Dependent Claim
41 words
A controller as claimed in claim 14, wherein the sensing means are adapted to sense the difference between the transient voltage at the anode of the thyristor means on commutation of the thyristor means and the voltage of the DC source.
Claim 6
Dependent Claim
80 words
A controller as claimed in claim 1 and having means for reversing the charge on the commutating capacitor relative to said first direction, means for preventing decay of charge on the commutating capacitor and further thyristor means which are rendered conducting to discharge said reversed charge on the commutating capacitor to commutate the thyristor means connecting the load to the DC source, wherein the sensing means are adapted to sense the voltage of the reversed charge on the commutating capacitor.
Claim 7
Dependent Claim
36 words
A controller as claimed in claim 2, wherein the circuit elements are adapted, when the voltage sensed by the sensing means exceeds said predetermined value, to operate so as to delay conduction of the thyristor means.
Claim 8
Dependent Claim
37 words
A controller as claimed in claim 2, wherein the circuit elements are adapted, when the voltage sensed by the sensing means exceeds said predetermined value, to operate so as to advance the commutation of the thyristor means.
Claim 9
Dependent Claim
103 words
A controller as claimed in claim 2, wherein the sensing means includes a multiturn coil disposed in close proximity to a section of the leads of the DC source, and wherein said control circuit means includes an oscillator means coupled to said thyristor means for supplying repetitive pulses to render said thyristor means conductive, wherein the voltage induced in the coil on commutation of the thyristor means when in excess of a predetermined value is employed to operate said control circuit means to so control the pulsing frequency of said oscillator as to reduce the conducting to nonconducting time of the thyristor means.
Claim 10
Dependent Claim
30 words
A controller as claimed in claim 8, wherein the oscillator is so controlled as to delay the succeeding pulse to said thyristor means connecting the load to the DC souRce.
Claim 11
Dependent Claim
65 words
A controller as claimed in claim 9, wherein there are provided means for reversing the charge on the commutating capacitor relative to said first direction, means for preventing decay of charge on the commutating capacitor and, further thyristor means which are rendered conducting to discharge said reversed charge on the commutating capacitor to thereby commutate the thyristor means connecting the load to the DC source.
Claim 12
Dependent Claim
80 words
A controller as claimed in claim 8 and having means for reversing the charge on the commutating capacitor relative to said first direction, means for preventing decay of charge on the commutating capacitor of further thyristor means which are rendered conducting to discharge said reversed charge on the commutating capacitor to thereby commutate the thyristor means connecting the load to the DC source wherein the oscillator is so controlled as to advance the succeeding pulse to said further thyristor means.
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) | 1974-12-20 | 1975-06-21 | 1975-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-20 | 1979-06-21 | 1979-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-20 | 1983-06-21 | 1983-12-21 | $7700.00 | Window Closed / Lapsed |