Patent EP0118947A1 successfully refreshed from Google Patents.
EP0118947A1
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EP
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Procedure for controlling the type of arc in an electrical furnace, and arc furnace which employs the procedure
Assignee: FERRIERE NORD SpA
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Filing: 1984-02-28
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Granted: —
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Expires: 2004-02-28
Abstract
Abstract This invention concerns a procedure for controlling the type of arc in an electrical furnace (F), which comprises the monitoring (R) of the short circuit power of the network line (L) during a period of inactivity of the arc, whereby the value thus monitored is processed (E) to determine a primary voltage (V) to be maintained at a transformer (T2) supplying the electrodes of the furnace (F), and whereby the processing (E) combines fixed parameters (P) and at least variable parameters relating to:- pre-set conditions of the arc (S).- conditions of a substation tap changer (VAR),- and line parameters (C) including at least the state of connection of banks of capacitors (C1-C2).The invention also concerns an arc furnace (F) which employs a procedure for controlling the type of arc according to the methods described herein.
Inventors
- 👤 Andrea Pittini
- 👤 Gianni Gensini
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 12:31
CPC Classifications
H; H05; H05B; H05B7/00; H05B7/02; H05B7/144; H05B7/148; H05B7/005; Y; Y02; Y02P; Y02P10/00; Y02P10/25
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
116 words
1 - Procedure for controlling the type of arc in an electrical furnace (F), which comprises the monitoring (R) of the short circuit power of the network line (L) during a period of inactivity of the arc, and by which the value thus monitored is processed (E) to determine a primary voltage (V) to be maintained at a transformer (T2) supplying the electrodes of the furnace (F), and by which the processing (E) combines fixed parameters (P) and at least variable parameters relating to: - pre-set conditions of the arc (S), - conditions of a substation tap changer (VAR), - and line parameters (C) including at least the state of connection of banks of capacitors (C1-C2).
Claim 2
Dependent Claim
116 words
1 - Procedure for controlling the type of arc in an electrical furnace (F), which comprises the monitoring (R) of the short circuit power of the network line (L) during a period of inactivity of the arc, and by which the value thus monitored is processed (E) to determine a primary voltage (V) to be maintained at a transformer (T2) supplying the electrodes of the furnace (F), and by which the processing (E) combines fixed parameters (P) and at least variable parameters relating to: - pre-set conditions of the arc (S), - conditions of a substation tap changer (VAR), - and line parameters (C) including at least the state of connection of banks of capacitors (C1-C2).
Claim 3
Dependent Claim
44 words
2 - Procedure for controlling the type of arc in an electrical furnace (F) as claimed in Claim 1, by which the establishment of the pre-set arc conditions (S) comprises at least one variable at least correlated with the voltage at the arc (Va).
Claim 4
Dependent Claim
65 words
3 - Procedure for controlling the type of arc in an electrical furnace (F) as claimed in Claims 1 and 2, by which the action of the processing group (E) to govern the voltage tap changer (VAR) takes place when the new value of primary voltage (V) thus obtainable is nearer to the optimum value calculated by the processing group (E) than the existing value.
Claim 5
Dependent Claim
37 words
4 - Procedure for controlling the type of arc in an electrical furnace (F) as claimed in any claim hereinbefore, by which at least one processing operation is carried out before the running of the furnace (F).
Claim 6
Dependent Claim
67 words
5 - Procedure for controlling the type of arc in an electrical furnace (F) as claimed in any claim hereinbefore, by which the processings (E) are carried out with parameters of arc (S) selected as necessary during the running of the furnace (F) and the value of short circuit power used in the processing is kept constant and the same as that monitored (R) at the beginning.
Claim 7
Dependent Claim
37 words
6 - Procedure for controlling the type of arc in an electrical furnace (F) as claimed in any claim hereinbefore, by which each processing includes calculations performed for at least one possible parameter of the line (C).
Claim 8
Dependent Claim
24 words
7 - Arc furnace (F) which employs a procedure for controlling the type of arc according to one or more of the claims hereinbefore.
References Cited (Backward Citations)
DE2544452A1
Cited
GB2000615A
Cited
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