US4259636A
Expired / Lapsed
US
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Monitoring device for semiconductor rectifiers
Assignee: BBC Brown Boveri AG Switzerland
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Filing: 1978-12-28
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Granted: 1981-03-31
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Expires: 1998-12-28
Abstract
Abstract A monitoring device for semiconductor rectifiers which are located in a three-phase current bridge circuit, in which the bridge circuit is provided with two semiconductor rectifiers per rectifier branch, including a current-sensitive detector circuit connected to each pair of semiconductor rectifiers of each branch through a resistor, wherein when the semiconductor rectifiers are intact, the sum of all current flowing through the resistors is zero, as detected by the current-sensitive detector circuit.
Inventors
- 👤 Werner Buser
- 👤 Hendrik Hoitink
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:03
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/26; G01R31/2607; G01R31/2632
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
144 words
A monitoring device for semiconductor rectifiers, which are located in a three-phase current bridge circuit connected to a three-phase power source, comprising: said bridge circuit comprising a plurality of rectifier branches, each branch having at least two pairs of semiconductor rectifiers per phase connected in series between a respective phase and a load, each pair having a series connection point to which is connected one side of a respective resistor, each resistor having a common value and the other sides thereof tied together at a common point to allow vector addition of all the currents flowing through said resistors; and a current sensitive detector coupled to said common point for detecting if said vector current is non-zero; wherein, when the semiconductor rectifiers are intact, the vector sum of all current flowing through the resistors is zero, as detected by said current sensitive detector circuit.
Claim 2
Dependent Claim
144 words
A monitoring device for semiconductor rectifiers, which are located in a three-phase current bridge circuit connected to a three-phase power source, comprising: said bridge circuit comprising a plurality of rectifier branches, each branch having at least two pairs of semiconductor rectifiers per phase connected in series between a respective phase and a load, each pair having a series connection point to which is connected one side of a respective resistor, each resistor having a common value and the other sides thereof tied together at a common point to allow vector addition of all the currents flowing through said resistors; and a current sensitive detector coupled to said common point for detecting if said vector current is non-zero; wherein, when the semiconductor rectifiers are intact, the vector sum of all current flowing through the resistors is zero, as detected by said current sensitive detector circuit.
Claim 3
Dependent Claim
58 words
A monitoring device according to claim 1, further comprising: the semiconductor rectifiers of each pair connected in series with one fuse element each and, in parallel fashion, series-connected to the three-phase power phases; and, the connecting point of each rectifier and it's associated series-connected fuse connected through said resistor to the input of said current sensitive detector circuit.
Claim 4
Dependent Claim
34 words
A monitoring device according to claim 2, further comprising: at least one other series circuit of a semiconductor rectifier and a fuse, connected in parallel with the semiconductor rectifiers and fuses of each pair.
Claim 5
Dependent Claim
13 words
A monitoring device according to claim 1, wherein the semiconductor rectifiers are diodes.
Claim 6
Dependent Claim
13 words
A monitoring device according to claim 1, wherein the semiconductor rectifiers are thyristors.
References Cited (Backward Citations)
SU237997A1
Cited
US4133017A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-30 | 1984-09-29 | 1985-03-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-30 | 1988-09-29 | 1989-03-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-30 | 1992-09-29 | 1993-03-31 | $7700.00 | Window Closed / Lapsed |