Method and device for measuring the rotational speed of a pulse-activated electric motor based on a frequency of current ripples
US7265538B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 2003 |
| Grant date | Sep 4, 2007 |
| Priority date | — |
| Expiry date | May 26, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P7/0094
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method and a device for measuring the speed of a pulse-activated electric motor are described. According to this method, the motor is fully activated at time intervals to be determined for a defined measuring time by the circuit element provided for timing and, in this time, the frequency of the current ripples, which is proportional to the motor speed, is measured. A current-proportional voltage measuring device is located on the circuit element, on whose load side are located an amplifier, filters, and an evaluation circuit in the form of a comparator for determining the frequency of the current ripples flowing in a measured phase during which the motor is fully activated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.