Bumpless rotating start
US5461296A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 20, 1993 |
| Grant date | Oct 24, 1995 |
| Priority date | — |
| Expiry date | Jul 20, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P1/029
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method for starting an unexcited, multiple phase, alternating current induction motor rotating at an unknown speed is provided. The method includes generating an output signal with an AC drive at a predetermined frequency in order to energize the motor. The output signal has independently adjustable frequency and voltage components. A speed reference is provided which is functionally related to the frequency of the output signal. The voltage of the output signal is ramped at a predetermined rate and the frequency of the output signal is adjusted such that the voltage of the output signal equals the motor's set point and the speed reference is substantially equal to the speed of the motor. The motor then enters the normal operating mode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.