US3593105A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Phase sequence insensitive firing circuit
Assignee: Louis Allis Co
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Filing: 1969-09-03
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Granted: 1971-07-13
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Expires: 1989-09-03
Abstract
Abstract A firing circuit for a phase controlled rectifier system employs the line to line phase voltage to be conducted by a pair of the thyristors of the phase controlled rectifier to develop the firing wave for controlling the firing of the thyristors. The line to line phase voltage is phase shifted a constant amount to produce the appropriate firing wave regardless of the phase sequence or order of connection of the source to the phase controlled rectifier system. Coupling, as by an OR gate, between firing pulse generators for thyristors of a pair, insures that whichever of the two is controlled to fire first because of the sequence of the phases of the source, the firing pulse is also applied to the other thyristor of the pair to cause it to fire.
Inventors
- 👤 Paul D Grohaugh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:49
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/02; H02M7/04; H02M7/12; H02M7/145; H02M7/155; H02M7/162; H02M7/1623; H02P; H02P7/00; H02P7/06; H02P7/18; H02P7/24; H02P7/28; H02P7/285; H02P7/292; H02P7/293; Y; Y10; Y10S; Y10S388/00; Y10S388/907; Y10S388/917
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
176 words
In a phase controlled rectifier system having complementary pairs of thyristors for supplying rectified line to line phase voltages to a load from a multiphase voltage source, a method of firing the thyristors of the phase controlled rectifier to insure ordered successive conduction for each line to line phase voltage regardless of the phase sequence of the multiphase source or the order of the connection of the multiphase source to the phase controlled rectifier system, comprising: electrically phase shifting the line to line phase voltage to be conducted by each complementary pair of thyristors to obtain a sinusoidal firing wave the phase shift of which, with respect to the line to line phase voltage to be conducted, remains the same regardless of the phase sequence or connection of the multiphase source; generating a firing pulse for one thyristor of each complementary pair at a time during the line to line voltage cycle as controlled by the corresponding firing wave; and coupling the firing pulse for the one thyristor to the other thyristor of the complementary pair.
Claim 2
Dependent Claim
176 words
In a phase controlled rectifier system having complementary pairs of thyristors for supplying rectified line to line phase voltages to a load from a multiphase voltage source, a method of firing the thyristors of the phase controlled rectifier to insure ordered successive conduction for each line to line phase voltage regardless of the phase sequence of the multiphase source or the order of the connection of the multiphase source to the phase controlled rectifier system, comprising: electrically phase shifting the line to line phase voltage to be conducted by each complementary pair of thyristors to obtain a sinusoidal firing wave the phase shift of which, with respect to the line to line phase voltage to be conducted, remains the same regardless of the phase sequence or connection of the multiphase source; generating a firing pulse for one thyristor of each complementary pair at a time during the line to line voltage cycle as controlled by the corresponding firing wave; and coupling the firing pulse for the one thyristor to the other thyristor of the complementary pair.
Claim 3
Dependent Claim
55 words
A method as recited in claim 1 wherein the line to line voltage to be conducted is phase shifted so that the negative to positive half-cycle of the sinusoidal firing wave begins at the time the line to line phase voltage to be conducted becomes more positive than the preceding line to line phase voltage.
Claim 4
Dependent Claim
23 words
A method as recited in claim 1 wherein the line to line voltage to be conducted is phase shifted 150 electrical degrees lagging.
Claim 5
Dependent Claim
226 words
In a phase controlled rectifier system for supplying a full wave rectified voltage to a load from a multiphase source including the phase controlled rectifier having a complementary pair of thyristors to conduct each of the line to line phase voltages of said multiphase source, wherein the firing of the thyristors is controlled by a control direct voltage and a sinusoidal firing wave, a firing circuit to insure firing of each of said pairs of thyristors for each successive line to line phase voltage regardless of the phase sequence of the multiphase source or the order of the connection of the multiphase source to the phase controlled rectifier system, comprising: electrical phase shift means coupled to the source to phase shift the line to line voltage to be conducted by a given pair of thyristors a fixed predetermined amount regardless of the phase sequence or connection of the multiphase source to obtain the sinusoidal firing wave; comparing means responsive to the sinusoidal firing wave and the control voltage to produce an output signal when the firing wave becomes equal in value to the control voltage; pulse generating means producing a firing pulse for one of the thyristors of said given pair in response to the output signal from said comparing means; and coupling means coupling the firing pulse to the other thyristor of said given pair.
Claim 6
Dependent Claim
226 words
In a phase controlled rectifier system for supplying a full wave rectified voltage to a load from a multiphase source including the phase controlled rectifier having a complementary pair of thyristors to conduct each of the line to line phase voltages of said multiphase source, wherein the firing of the thyristors is controlled by a control direct voltage and a sinusoidal firing wave, a firing circuit to insure firing of each of said pairs of thyristors for each successive line to line phase voltage regardless of the phase sequence of the multiphase source or the order of the connection of the multiphase source to the phase controlled rectifier system, comprising: electrical phase shift means coupled to the source to phase shift the line to line voltage to be conducted by a given pair of thyristors a fixed predetermined amount regardless of the phase sequence or connection of the multiphase source to obtain the sinusoidal firing wave; comparing means responsive to the sinusoidal firing wave and the control voltage to produce an output signal when the firing wave becomes equal in value to the control voltage; pulse generating means producing a firing pulse for one of the thyristors of said given pair in response to the output signal from said comparing means; and coupling means coupling the firing pulse to the other thyristor of said given pair.
Claim 7
Dependent Claim
30 words
A firing circuit as recited in claim 4 wherein said electrical phase shift means comprises resistor-capacitor means for providing a lagging phase shift 150* the line to line phase voltage.
Claim 8
Dependent Claim
25 words
A firing circuit as recited in claim 5 wherein said electrical phase shift means phase shifts the line to line phase voltage 150electrical degrees lagging.
Claim 9
Dependent Claim
38 words
A firing circuit as recited in claim 4 wherein for a given phase sequence the other of said given pair of thyristors conducted the preceding line to line phase voltage and is refired by the coupled firing pulse.
Claim 10
Dependent Claim
16 words
A firing circuit as recited in claim 4 wherein said coupling means is an OR gate.
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) | 1974-07-12 | 1975-01-11 | 1975-07-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-12 | 1979-01-11 | 1979-07-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-12 | 1983-01-11 | 1983-07-13 | $7700.00 | Window Closed / Lapsed |