Method and apparatus for sensing voltage in an automatic transfer switch system
US7157811B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 28, 2003 |
| Grant date | Jan 2, 2007 |
| Priority date | — |
| Expiry date | Jun 6, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J9/068
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An Automatic Transfer Switch System includes a control circuit in which high frequency transformers, designed to operate linearly in a frequency range above the operating frequency range of utility-level power, are employed for voltage sensing. An output signal from a high frequency line matching transformer is received by a microprocessor which evaluates the signal for both a voltage level and frequency and uses these values as indices to an empirically-derived look-up table which provides an actual voltage level to the microprocessor. The actual voltage value can then be evaluated by the microprocessor to determine if and when the power delivered to a load should be supplied by a first or a second power supply.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.