Phase-shifting transformer system
US5166597A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 1991 |
| Grant date | Nov 24, 1992 |
| Priority date | — |
| Expiry date | Aug 8, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E40/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A faster, more controllable phase-shifting transformer system is provided, along with a method of retrofitting and upgrading a preexisting system for faster operation, and a method of applying a desired phase shift to the voltage on a polyphase transmission line. A phase-shifting transformer set has series and regulating transformers coupled together by a switching network, An optional modulator modulates the phase shift voltage about a nominal level established by the switching network. The modulator may be a variable susceptance switched inductor or a switched capacitor, or a variable source device, such as a voltage source inverter device or a synchronous condenser. A thyristor augmented switching network may have a pair of thyristor valves augmenting a reversing switch, or a thyristor augmented load tap changer for varying the phase shift discreet step magnitude. Continuous control over the effective phase shift is obtained by partial conduction control of a thyristor valve with a harmonic filter in parallel with each excited winding of the series transformer, and by including a harmonic filter across the ends of regulating winding of the regulating transformer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.