Data acquisition system for the computer control of aluminum smelters
US4638441A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 31, 1984 |
| Grant date | Jan 20, 1987 |
| Priority date | — |
| Expiry date | May 31, 2004 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25C3/20
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Disclosed is a system for measuring cell potentials in an aluminum potline having a plurality of cells connected in series. The system enables better control of the cells than the current method which calculates cell resistance on the basis of measured cell potentials and potline current but an assumed value of back e.m.f. The present invention uses corrected voltage measurements and provides a decentralized, current independent cell potential measuring system which converts simultaneously all cell potentials during a normal integration period (e.g. 1 second) into a value corresponding to the potline current when it is at its normal (set-point) value. Simultaneously, various possible back e.m.f. values are measured with the same current relationship and computations made of the error caused by the non-ohmic portion of the cell potential when the current deviates from its normal (set-point) value. Sudden changes in current enable correct values of back e.m.f. to be determined.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.