Dynamic braking of direct current motors
US4450388A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 22, 1982 |
| Grant date | May 22, 1984 |
| Priority date | — |
| Expiry date | Oct 22, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P3/12
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A dynamic braking system for a D.C. traction motor which is driven from an asymmetric bridge rectifier having freewheel diodes to permit circulation of motor generated current. The system employs field reversal to ensure a generated (braking) current direction the same as for motoring and this facility permits injection current braking by phasing up the supply bridges when the motor is braking with full excitation. The brake resistance is in two parts one of which forms an uncontrolled arm of the bridge, this part of the resistance being shunted by a thyristor. Part way through an injection braking process the supply bridge is phased down, the resistance bridge arm shorted out and the supply bridge phased up again. Lower losses and greater braking efficiency result.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.