Protective circuit for series capacitor banks
US4703385A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 23, 1986 |
| Grant date | Oct 27, 1987 |
| Priority date | — |
| Expiry date | Apr 23, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H7/16
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
As overvoltage protection for a series capacitor (C1-C5) in a high-voltage network a voltage-dependent resistor (Z6), built up of metal oxide varistors, is arranged in parallel with the capacitor. In parallel with the resistor there is a spark gap means consisting of two series-connected spark gaps (G1, G2) for shunting the resistor in case of overload thereof. The energy for triggering the spark gap means is obtained from an auxiliary capacitor (C5), which is charged during operation, and is supplied to one of the spark gaps (G2) via a switching means (T1, T2), controlled by an overload detector (CU), and a pulse transformer (TR). A metal oxide varistor (Z5) is connected in series with the high voltage winding of the transformer. The transformer is connected so that the triggering pulse is in opposition to the voltage across the series capacitor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.