Device for detecting a ground fault in the rotor winding of an electric machine
US4667262A · kind A · utility
7Cited by
7References
15Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 12, 1984 |
| Grant date | May 19, 1987 |
| Priority date | — |
| Expiry date | Jun 12, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H7/065
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In the invention, a ground current, impressed, in the case of a ground fault, by an offset-voltage source connected into an earth line and capacitively coupled to the rotor winding, is detected both in the ground line and in the exciter circuit via at least one current transformer which is preferably constructed as a ring-core transformer. By suitable summing of the ground current flowing in the ground line with that flowing in the exciter circuit, an indication is achieved which is selective with respect to the location of the ground fault in the exciter circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.