Phase shifter
US4661763A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 6, 1985 |
| Grant date | Apr 28, 1987 |
| Priority date | — |
| Expiry date | Feb 6, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H7/20
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Phase shifters are used in meshed, multi-phase power supply systems for improving their transmission stability and for load-flow regulating purposes. In order to be able to use a less costly exciter transformer of lower rating or the tertiary or compensation winding of a system coupling transformer for generating intermediate-circuit voltages as a function of system input voltages, a resonant circuit is provided between the exciter transformer and an auxiliary transformer. In this resonant circuit consisting of series-connected capacitors and inductive resistances which are connected to taps between these capacitors and can be switched in and out by means of alternating-current switches, tap voltages are generated which are supplied to the primary windings of the auxiliary transformer. At the secondary windings, connected in series with phase conductors of the auxiliary transformer, auxiliary voltages occur which are superimposed on the system input voltages and effect the desired phase shifts. Instead of air chokes which can be switched off, chokes with a ferromagnetic core or the impedance of a transformer, the secondary winding of which can be short-circuited by means of an alte…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.