Method and apparatus for measuring electricity
US4801874A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 27, 1987 |
| Grant date | Jan 31, 1989 |
| Priority date | — |
| Expiry date | Feb 27, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R21/1331
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The method and apparatus disclosed relates to the electronic measurement of the electricity used by a load. The apparatus generates a rectified voltage signal proportional to the load voltage. A frequency modulated pulse train is generated in response to the load voltage signal, with the frequency of the pulses being proportional to the instantaneous amplitude of the rectified load voltage. A load current signal is generated that is proportional to the load current. A logic circuit gates the load current signal during each pulse of the frequency modulated pulse train to generate a signal representing the product of the instantaneous load voltage and the instantaneous load current. This signal from the logic means may be integrated over time to generate a signal representing the amount of electric energy used by the load. A method for practicing this invention is also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.