Tap switching protection circuit
US4860145A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 11, 1985 |
| Grant date | Aug 22, 1989 |
| Priority date | — |
| Expiry date | Oct 11, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H7/055
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A protection circuit is provided for a tap switching line voltage regulator of the type which selectively switches in one of a predetermined number of taps on a winding of a transformer. The selective switching of the taps is controlled in response to the sensed load voltage to provide a regulated voltage to a load in the presence of a varying input line voltage. The tap switching line voltage regulator in response to the sensed load voltage controls the conductive state of a solid state series switching element in each of the switched tap lines. The protection circuit provides current limiting inductors in series with each of the solid state switching elements with all the inductors being wound on a common magnetic core. When switching from one tap to another tap, the tap switching line volage regulator in response to the sensed voltage operates to select an adjacent tap to the tap currently selected. Thus, tap switching proceeds in a sequential fashion up and down along the taps. The series inductors are wound on the common magnetic core such that the direction of the windings alternates between adjacent taps. Accordingly, the protection circuit provides a current limiting impeda…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.