Apparatus for maintaining synchronism of an inverter-synchronous machine drive system at light or zero machine loads
US4258302A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 28, 1979 |
| Grant date | Mar 24, 1981 |
| Priority date | — |
| Expiry date | Sep 28, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P25/024
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
To achieve synchronization of an inverter-synchronous machine drive system, feedback of a phase angle signal, derived in part from stator current drawn by, and voltage supplied to, the synchronous machine, is provided to control the frequency of inverter thyristor conduction. At light or zero synchronous machine load conditions, machine stator current may be of insufficient magnitude to permit derivation of the phase angle feedback signal; therefore, substitute simulated stator current signals, proportional to a preselected combination of inverter thyristor gating pulses, are utilized to derive the phase angle feedback signal, thereby allowing inverter-synchronous machine drive synchronism to be maintained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.