C-Dump topology noise reduction
US5920176A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 18, 1998 |
| Grant date | Jul 6, 1999 |
| Priority date | — |
| Expiry date | Aug 18, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P25/092
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method and circuit for controlling a switched reluctance motor are provided. The method includes the steps of controlling a current in a phase coil of a motor phase of the motor during an active stage of the motor phase and controlling the current in the phase coil during an inactive stage of the motor phase. The latter step includes the substep of increasing the level of current in the phase coil for a predetermined period of time during the inactive stage of the motor phase. By increasing the current level during the inactive stage, the rate of current dissipation is reduced, thereby reducing acoustic noise. A circuit in accordance with the present invention includes a pair of one-shot circuits connected together in series and responsive to the end of the active stage of the motor phase. The second one-shot circuit generates an output signal that closes a switch connected to a phase coil of a motor phase of the motor for a predetermined period of time during the inactive stage of the motor phase. Closing the switch causes a level of current in the phase coil to increase during the inactive stage of the motor phase, thereby slowing the rate of current dissipation and reducing ac…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.