Cost reduced synchronized-switching contactor
US10211005B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 21, 2016 |
| Grant date | Feb 19, 2019 |
| Priority date | — |
| Expiry date | Aug 17, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2009/307
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A simple, economically efficient, synchronized switching system for control of a three phase motor contactor utilizes only Voltage monitoring to determine zero crossings and knowledge of the sinusoidal power waveforms and operational delay period of the contactor, to synchronize operation of the contacts at low power. The phases can be serially utilized for zero crossing detection upon Close or Open commands, so as to spread the wear over each set of contacts. Expensive metal at the contact surfaces can therefore be used more efficiently. For arc energy reduction upon contact opening, knowledge of Line-Load Voltage on at least one phase can be used to derive an empirical determination of the voltage angle at opening which yields the lowest arc energy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.