Power factor control system for inverter-driven a-c induction motor
US4291264A · kind A · utility
11Cited by
8References
9Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 4, 1979 |
| Grant date | Sep 22, 1981 |
| Priority date | — |
| Expiry date | Sep 4, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J3/1892
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The power factor in an inverter-driven induction motor is held relatively constant at a desired optimum value, despite variations in mechanical loading on the motor, by monitoring the d-c bus current to determine the ratio of real and reactive currents, thereby to detect the actual power factor. The actual and desired power factors are then effectively compared and the resulting error signal is fed back to the inverter's d-c power supply to adjust the inverter output voltage to change the reactive current to the extent necessary to maintain the desired power factor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.