US3634748A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Static inverter circuits
Assignee: Individual
•
Filing: 1970-06-03
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Granted: 1972-01-11
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Expires: 1990-06-03
Abstract
Abstract A method of regulating the output voltage of a complementary impulse commutated inverter which incorporates two silicon controlled rectifiers and has a commutation circuit which is arranged such that when the one silicon controlled rectifier is nonconductive and the other silicon controlled rectifier is conductive, firing of the nonconductive silicon controlled rectifier with a short trigger pulse of duration less than the turnoff time of each of the two silicon controlled rectifiers turns off both silicon controlled rectifiers in succession. A series of substantially similar signals are applied alternately to the gate of the one and the other silicon controlled rectifier, each signal comprising a short trigger pulse of a duration less than the turnoff time of each of the silicon controlled rectifiers followed after an interval of time by a long control pulse of duration longer than the turnoff time of each of the silicon controlled rectifiers and proportional to the required amplitude of the output voltage of the inverter. The one silicon controlled rectifier is fired when it is nonconductive and the other silicon controlled rectifier is conductive by application of the short trigger pulse of a signal to the gate of the one silicon controlled rectifier, thereby to turn off both silicon controlled rectifiers in succession. The one silicon controlled rectifier is subsequently refired by application of the long control pulse of the signal. The duration of the long pulse is varied to regulate the output voltage of the inverter. Also apparatus for carrying out the method comprising an inverter of the type stated, pulse-generating means operative to apply signals as specified alternately to the gate of the one and the other silicon controlled rectifier, and control means associated with the pulse-generating means and operative to vary the duration of the long control pulse of each signal.
Inventors
- 👤 Bernhard Siegfried Rudert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:27
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/42; H02M7/44; H02M7/48; H02M7/505; H02M7/515; H02M7/525
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
238 words
A method of regulating the output voltage of a complementary impulse commutated inverter incorporating two silicon controlled rectifiers and having a commutation circuit which is arranged such that when the one silicon controlled rectifier is nonconductive and the other silicon controlled rectifier is conductive, firing of the nonconductive silicon controlled rectifier with a short trigger pulse of duration less than the turnoff time of each of the two silicon controlled rectifiers turns off both silicon controlled rectifiers in succession, includes the steps of applying a series of substantially similar signals alternately to the gate of the one and the other silicon controlled rectifier, each signal comprising a short trigger pulse of a duration less then the turnoff time of each of the silicon controlled rectifiers followed after an interval of time by a long control pulse of a duration longer than the turnoff time of each of the silicon controlled rectifiers and proportional to the required amplitude of the output voltage of the inverter; firing the one silicon controlled rectifier when it is nonconductive and the other silicon controlled rectifier is conductive by application of the short trigger pulse of a signal to the one gate of the one silicon controlled rectifier, thereby to turn off both silicon controlled rectifiers in succession; subsequently refiring the one silicon controlled rectifier by application of tHe long control pulse of the signal; and varying the duration of the long control pulse.
Claim 2
Independent Claim
238 words
A method of regulating the output voltage of a complementary impulse commutated inverter incorporating two silicon controlled rectifiers and having a commutation circuit which is arranged such that when the one silicon controlled rectifier is nonconductive and the other silicon controlled rectifier is conductive, firing of the nonconductive silicon controlled rectifier with a short trigger pulse of duration less than the turnoff time of each of the two silicon controlled rectifiers turns off both silicon controlled rectifiers in succession, includes the steps of applying a series of substantially similar signals alternately to the gate of the one and the other silicon controlled rectifier, each signal comprising a short trigger pulse of a duration less then the turnoff time of each of the silicon controlled rectifiers followed after an interval of time by a long control pulse of a duration longer than the turnoff time of each of the silicon controlled rectifiers and proportional to the required amplitude of the output voltage of the inverter; firing the one silicon controlled rectifier when it is nonconductive and the other silicon controlled rectifier is conductive by application of the short trigger pulse of a signal to the one gate of the one silicon controlled rectifier, thereby to turn off both silicon controlled rectifiers in succession; subsequently refiring the one silicon controlled rectifier by application of tHe long control pulse of the signal; and varying the duration of the long control pulse.
Claim 3
Dependent Claim
29 words
A method as claimed in claim 1, wherein the time interval between the commencement of the short triggering pulse and the termination of the long control pulse is fixed.
Claim 4
Dependent Claim
53 words
A method as claimed in claim 1, including the step of providing a tuned circuit having a resonant frequency in the order of or higher than the second harmonic of the operating frequency of the inverter, the resonant frequency of the tuned circuit controlling the range of variation of the inverter output voltage.
Claim 5
Dependent Claim
54 words
A method as claimed in claim 1, wherein during the interval of time between the application of the short trigger pulse and the long control pulse of a signal to the gate of the one silicon controlled rectifier, at least one regulating pulse is applied to the gate of the other silicon controlled rectifier.
Claim 6
Dependent Claim
62 words
A method as claimed in claim 1, wherein the last pulse of a series of signals applied to the gates of the thyristors of the inverter is a short pulse applied to the gate of the silicon controlled rectifier which is nonconductive at that time, such short pulse acting to turn off both silicon controlled rectifiers and terminate operation of the inverter.
Claim 7
Dependent Claim
20 words
A method as claimed in claim 1, wherein the output current of the inverter is limited to a predetermined value.
Claim 8
Dependent Claim
40 words
A method as claimed in claim 2, wherein the time interval between the commencement of the short triggering pulse and termination of the long control pulse is substantially equal to the duration of half an operating cycle of the inverter.
Claim 9
Dependent Claim
30 words
A method as claimed in claim 4, wherein at least one regulating pulse is also applied to the gate of the one silicon controlled rectifier during such interval of time.
Claim 10
Dependent Claim
195 words
Complementary impulse commutated inverter apparatus including a pair of silicon controlled rectifiers; a commutation circuit; a center-tapped transformer connected to the commutation circuit; the commutation circuit being arranged such that when the one silicon controlled rectifier is nonconductive and the other silicon controlled rectifier is conductive, firing of the nonconductive silicon controlled rectifier with a short pulse of duration less than the turnoff time of each silicon controlled rectifier, causes both silicon controlled rectifiers to be tuned off in succession; pulse-generating means connected to the gates of the two silicon controlled rectifiers, the pulse-generating means being operative to apply a series of signals alternately to the gate of the one and the other silicon controlled rectifier, each signal comprising a short triggering pulse of a duration shorter than the turnoff time of each silicon controlled rectifier followed after an interval of time by a long controlled pulse of a duration longer than the turnoff time of each silicon controlled rectifier and proportional to the required amplitude of the output voltage of the inverter; and control means associated with the pulse-generating means and operative to vary the duration of the long control pulse of each signal.
Claim 11
Dependent Claim
195 words
Complementary impulse commutated inverter apparatus including a pair of silicon controlled rectifiers; a commutation circuit; a center-tapped transformer connected to the commutation circuit; the commutation circuit being arranged such that when the one silicon controlled rectifier is nonconductive and the other silicon controlled rectifier is conductive, firing of the nonconductive silicon controlled rectifier with a short pulse of duration less than the turnoff time of each silicon controlled rectifier, causes both silicon controlled rectifiers to be tuned off in succession; pulse-generating means connected to the gates of the two silicon controlled rectifiers, the pulse-generating means being operative to apply a series of signals alternately to the gate of the one and the other silicon controlled rectifier, each signal comprising a short triggering pulse of a duration shorter than the turnoff time of each silicon controlled rectifier followed after an interval of time by a long controlled pulse of a duration longer than the turnoff time of each silicon controlled rectifier and proportional to the required amplitude of the output voltage of the inverter; and control means associated with the pulse-generating means and operative to vary the duration of the long control pulse of each signal.
Claim 12
Dependent Claim
38 words
Inverter apparatus as claimed in claim 9, wherein the pulse-generating means is adapted always to terminate a series of signals with a short pulse, operative to turn off both silicon controlled rectifiers and terminate operation of the inverter.
Claim 13
Dependent Claim
59 words
Inverter apparatus as claimed in claim 9, wherein the pulse-generating means is operative to apply, during the interval of time between the application of the short trigger pulse and the long control pulse of a signal to the gate of the one silicon controlled rectifier, at least one regulating pulse to the gate of the other silicon controlled rectifier.
Claim 14
Dependent Claim
57 words
Inverter apparatus as claimed in claim 9, including a commutation capacitor connected across the center-tapped transformer, and a filter choke connected to the center-tapped transformer, the commutation capacitor and the filter choke forming a tuned circuit having a resonant frequency in the order of, or greateR than, the second harmonic of the operating frequency of the inverter.
Claim 15
Dependent Claim
12 words
Inverter apparatus as claimed in claim 9, including output current limiting means.
Claim 16
Dependent Claim
35 words
Inverter apparatus as claimed in claim 11 wherein the pulse generator is operative also to apply at least one regulating pulse to the gate of the one silicon controlled rectifier during such interval of time.
Claim 17
Dependent Claim
59 words
Inverter apparatus as claimed in claim 13, wherein a series tuned filter circuit is connected to the center-tapped transformer; and the output current-limiting means comprises current-sensitive means adapted to alter the effective Q value of the tuned filter circuit to increase the losses in the filter circuit such that the maximum output current does not exceed a predetermined value.
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) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |