Patent US3900792A successfully refreshed from Google Patents.
US3900792A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for generating reactive power
Assignee: Siemens AG
•
Filing: 1974-01-03
•
Granted: 1975-08-19
•
Expires: 1994-01-03
Abstract
Abstract An improved method and apparatus for generating reactive power in an installation which includes a capacitor bank and two controlled converters connected to an A-C system of at least one phase in which the two controlled converters are coupled to each other on their DC sides through a smoothing choke with the converters controlled in a control range with a differing control angles. In the present invention, the control angles of both converters are controlled in such a manner that their sum is always smaller by a predetermined amount than a 180* thereby permitting simpler control and a reduced size of smoothing coil to be used.
Inventors
- 👤 Gottfried Moltgen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:20
CPC Classifications
H; H02; H02J; H02J3/00; H02J3/18; H02J3/1821; H02J3/1835; H02J3/1842; H02J3/185; Y; Y02; Y02E; Y02E40/00; Y02E40/20
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
101 words
A method for the operation of an arrangment for generating reactive power, which arrangment includes a capacitor installation and two controlled converters, each connected to an A-C system having at least one phase, with the two controlled converters connected to each other on the D-C side through a smoothing choke and wherein the converters are controlled in a control range with control angles which differ from each other, except for a common control range limit comprising the steps of controlling the control angles of the two converters such that their sum is always smaller than 180 by a predetermined angular amount.
Claim 2
Independent Claim
101 words
A method for the operation of an arrangment for generating reactive power, which arrangment includes a capacitor installation and two controlled converters, each connected to an A-C system having at least one phase, with the two controlled converters connected to each other on the D-C side through a smoothing choke and wherein the converters are controlled in a control range with control angles which differ from each other, except for a common control range limit comprising the steps of controlling the control angles of the two converters such that their sum is always smaller than 180 by a predetermined angular amount.
Claim 3
Dependent Claim
36 words
The method according to claim 1 wherein the predetermined angular amount is chosen so that for equal control angles a D-C current corresponding to the largest required value of reactive load flows through the smoothing choke.
Claim 4
Dependent Claim
112 words
An arrangment for the generation of reactive power in an A-C system having at least one phase and which includes a capacitor installation across the A-C system comprising: a. first and second controlled converters connected in series on their D-C side through a smoothing choke; b. a transformer having its primary winding coupled to said first and second converters; c. first and second control units providing firing pulses to said first and second converters respectively; and d. means to provide first and second control voltages to said first and second control units, said means providing control voltage outputs which vary from a first predetermined value by the same amount in opposite directions.
Claim 5
Dependent Claim
112 words
An arrangment for the generation of reactive power in an A-C system having at least one phase and which includes a capacitor installation across the A-C system comprising: a. first and second controlled converters connected in series on their D-C side through a smoothing choke; b. a transformer having its primary winding coupled to said first and second converters; c. first and second control units providing firing pulses to said first and second converters respectively; and d. means to provide first and second control voltages to said first and second control units, said means providing control voltage outputs which vary from a first predetermined value by the same amount in opposite directions.
Claim 6
Dependent Claim
61 words
The arrangement according to claim 3 wherein said first and second control voltages each consist of a fixed control voltage component which is the same for both and a superimposed variable control voltage component which is the same absolute magnitude but of opposite sign for both and wherein said variable voltage components are variable from zero to a second predetermined value.
Claim 7
Dependent Claim
17 words
The arrangment according to claim 4 and further including means for adjusting said fixed control voltage component.
Claim 8
Dependent Claim
36 words
The arrangement according to claim 4 wherein each of said control units includes a summing amplifier at its input with said fixed and variable components being provided as inputs to said amplifier and being superimposed thereby.
Claim 9
Dependent Claim
37 words
The arrangement according to claim 5 wherein each of said control unit includes a summing amplifier at its input with said fixed and variable voltage components being provided as inputs to said amplifier and being superimposed thereby.
Claim 10
Dependent Claim
52 words
The arrangment according to claim 3 and further including: a. means for measuring actual reactive power; b. means for pre-setting a nominal reactive power value; and c. means to develop said control voltages as a function of the deviation between the preset nominal reactive power value and the actual reactive power value.
Claim 11
Dependent Claim
52 words
The arrangement according to claim 7 and further including: a. means for measuring actual reactive power; b. means for presetting a nominal reactive power value; and c. means to develop said control voltages as a function of the deviation between the preset nominal reactive power value and the actual reactive power value.
Claim 12
Dependent Claim
17 words
The invention according to claim 3 wherein said A-C system is used to supply an arc furnace.
Claim 13
Dependent Claim
79 words
The arrangment according to claim 3 wherein said control units provide firing pulses at a control angle which is directly proportional to a control voltage input and said means providing first and second control voltages thereby provide a control voltage resulting in control angles which differ from eAch other, except for a common control range limit, and are sch that their sum is alway smaller than 180 * by a predetermined angular amount proportional to said first 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) | 1978-08-18 | 1979-02-17 | 1979-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-18 | 1983-02-17 | 1983-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-18 | 1987-02-17 | 1987-08-19 | $7700.00 | Window Closed / Lapsed |