Operation coil drive device for magnetic contactor
US10424452B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 20, 2018 |
| Grant date | Sep 24, 2019 |
| Priority date | — |
| Expiry date | Feb 20, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K17/64
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An operation coil drive device includes a drive control unit to perform control to set, for a semiconductor switching element to switch on and off the source voltage applied to an operation coil of a magnetic contactor, a larger ON/OFF time ratio for a circuit-closing control and a smaller ON/OFF time ratio for a holding control, wherein the drive control unit includes: a circuit-closing-control inductance calculation unit to calculate an inductance of the operation coil immediately after a start of the circuit-closing control; a circuit-closing-control resistance value calculation unit to calculate a direct current resistance value of the operation coil based on the calculation result; and a circuit-closing-control switching correction unit to correct the ON/OFF time ratio of the semiconductor switching element for the circuit-closing control based on the calculation result.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.