Motor current detection apparatus, motor controller, and electric power tool
US8933653B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 2, 2012 |
| Grant date | Jan 13, 2015 |
| Priority date | — |
| Expiry date | Feb 3, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P6/28
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A motor current detection apparatus in the present invention includes: a current detection unit, a first filter, and a second filter. The detection unit detects a conduction current flowing from a battery to a brushless motor and outputs a conduction current signal corresponding to the detected conduction current. The first filter extracts a first current signal which is included in the conduction current signal outputted from the detection unit and is a signal component in a frequency band equal to or lower than a predetermined first cutoff frequency. The second filter extracts a second current signal which is included in the conduction current signal outputted from the detection unit and is a signal component in a predetermined frequency band within a frequency band equal to or lower than a predetermined second cutoff frequency higher than the first cutoff frequency and having the second cutoff frequency as a maximum value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.