US3823362A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coordinated master-slave converter system for variable-power tank loads
Assignee: General Electric Co
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Filing: 1973-02-02
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Granted: 1974-07-09
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Expires: 1993-02-02
Abstract
Abstract A plural converter system, including parallel-connected currentsource inverters, efficiently delivers alternating current to a tank load having variable power requirements. One of these inverters is a master and the remainder are slaves, and each has a maximum power rating and a loading range that is a fraction of the corresponding parameters of the load. The master inverter is started initially to charge the load, and the slaves are selectively controlled in response to the actual power requirement of the load so that the proper converters are running to supply the load demand without exceeding either the maximum unit rating or the limited range of any individual converter.
Inventors
- 👤 R Bailey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 12:52
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/02; H02M7/04; H02M7/12; H02M7/145; H02M7/155; H02M7/162
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
335 words
An electric power system for supplying alternating current to a tank load having variable power utilization capacity between predetermined minimum and rated magnitudes of load current, comprising: a. a master electric converter having a predetermined maximum power rating at which it may safely operate and including i. a first rectifier circuit having a-c and d-c terminals, said a-c terminals being adapted to be connected to a source of alternating voltage of predetermined main frequency, ii. a first current smoothing inductor, and iii. a first current-source, load-commutated inverter having input terminals connected via said first inductor to the d-c terminals of said first rectifier circuit and having a pair of output terminals connected to a subcircuit formed of a series compensating capacitor and the load, said first inverter being operative to supply the load with current of at least said minimum magnitude; b. a slave electric converter having a predetermined maximum power rating at which it may safely operate and including, i. a second rectifier circuit having a-c terminals adapted to be connected to said alternating voltage source and having d-c terminals, ii. a second current smoothing inductor, and iii. a second current-source, load-commutated inverter having input terminals connected via said second inductor to the d-c terminals of said second rectifier circuit and having a pair of output terminals connected across the load, said second inverter having the ability when said slave converter is operative to supply a portion of the total load current in parallel with that supplied by said first inverter; c. means for starting said first inverter to effectuate initial charging of the tank load and for running all of said inverters at a desired operating frequency; and d. control means for rendering said slave converter operative after the first inverter has been started only if the actual power requirement of the load is then greater than said power rating of said master converter, in which event both the first and the second inverters supply proportional shares of alternating current to the load.
Claim 2
Dependent Claim
335 words
An electric power system for supplying alternating current to a tank load having variable power utilization capacity between predetermined minimum and rated magnitudes of load current, comprising: a. a master electric converter having a predetermined maximum power rating at which it may safely operate and including i. a first rectifier circuit having a-c and d-c terminals, said a-c terminals being adapted to be connected to a source of alternating voltage of predetermined main frequency, ii. a first current smoothing inductor, and iii. a first current-source, load-commutated inverter having input terminals connected via said first inductor to the d-c terminals of said first rectifier circuit and having a pair of output terminals connected to a subcircuit formed of a series compensating capacitor and the load, said first inverter being operative to supply the load with current of at least said minimum magnitude; b. a slave electric converter having a predetermined maximum power rating at which it may safely operate and including, i. a second rectifier circuit having a-c terminals adapted to be connected to said alternating voltage source and having d-c terminals, ii. a second current smoothing inductor, and iii. a second current-source, load-commutated inverter having input terminals connected via said second inductor to the d-c terminals of said second rectifier circuit and having a pair of output terminals connected across the load, said second inverter having the ability when said slave converter is operative to supply a portion of the total load current in parallel with that supplied by said first inverter; c. means for starting said first inverter to effectuate initial charging of the tank load and for running all of said inverters at a desired operating frequency; and d. control means for rendering said slave converter operative after the first inverter has been started only if the actual power requirement of the load is then greater than said power rating of said master converter, in which event both the first and the second inverters supply proportional shares of alternating current to the load.
Claim 3
Dependent Claim
64 words
The system of claim 1 wherein said control means comprises means for monitoring the magnitudes of the total current supplied to the load and the voltage across the load and for causing said slave converter to become operative in response to a predetermined range of ratios of load current, in percent of rated load current, to load voltage, in percent of rated load voltage.
Claim 4
Dependent Claim
146 words
The system of claim 1 additionally comprising: e. an additional slave electric converter having a predetermined maximum power rating at which it may safely operate and including: i. a third rectifier circuit having a-c terminals adapted to be connected to said alternating voltage source and having d-c terminals ii. a third current smoothing inductor, and iii. a third current-source, load-commutated inverter having input terminals connected via said third inductor to the d-c terminals of said third rectifier circuit and having a pair of output terminals connected across the load, said additional slave converter being rendered operative by said control means only if the actual power requirement of the load is greater than the aggregate of the power ratings of the master and first-mentioned slave converters after said first inverter has been started, whereupon the first, second, and third inverters all supply alternating current to the load.
Claim 5
Dependent Claim
82 words
The system of claim 3 wherein said control means comprises means for monitoring the magnitudes of the total load current and the load voltage and means for causing said first-mentioned slave converter to become operative in response to a first predetermined range of ratios of load current, in percent of rated load current, to load voltage, in percent of rated load voltage, and for causing both of said slave converters to become operative if such ratio is within a second predetermined range.
Claim 6
Dependent Claim
23 words
The system of claim 4 wherein both of said slave converters are concurrently rendered operative if said ratio is within said second range.
Claim 7
Dependent Claim
80 words
The system of claim 1 wherein each of said first and second rectifier circuits comprises a plurality of periodically triggered thyristors which are interconnected and arranged to form a phase-controlled full-wave rectifier circuit, and wherein said control means is effective to inhibit the triggering of the thyristors forming said second rectifier circuit except when said slave converter is rendered operative in response to the actual power requirement of the load being greater than said power rating of said master converter.
Claim 8
Dependent Claim
44 words
The system of claim 1 additionally comprising a compensating capacitor, means for connecting the output terminals of said first inverter in series with said compensating capacitor across the load, and means for connecting the output terminals of said second inverter directly across the load.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-07-08 | 1978-01-07 | 1978-07-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-08 | 1982-01-07 | 1982-07-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-08 | 1986-01-07 | 1986-07-09 | $7700.00 | Window Closed / Lapsed |