Overload protection system for three-phase submersible pump motor
US4000446A · kind A · utility
69Cited by
3References
2Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 4, 1975 |
| Grant date | Dec 28, 1976 |
| Priority date | — |
| Expiry date | Jun 4, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/0935
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Overload protection of a three-phase submersible pump motor, such as the type used downhole in an oil well, is obtained with a solid state digital logic control system that monitors each of the three phase currents and shuts the pump motor down if any of those phase currents indicates an overload condition. A time delay is introduced before shutdown to avoid undesired nuisance shutdowns otherwise caused by transient or momentary conditions. The shutdown time delay is variable and is inversely proportional to the amount of overload in order that greater overloads result in faster shutdowns.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.