Control circuit for suppression of line resonances in current feedback pulse width modulation control systems with a minimum d-c filter
US4473790A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 3, 1983 |
| Grant date | Sep 25, 1984 |
| Priority date | — |
| Expiry date | Jan 3, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P27/08
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A variable speed a-c drive motor is controlled by a current feedback pulse width modulation scheme which effectively isolates the controlled motor current from variations in the input d-c voltage. An additional control loop is provided to superimpose a control signal on the amplitude command input circuit of the pulse width modulation control scheme. The additional loop responds to line current and particularly line current resonance between the input d-c filter and the line inductance. Instantaneous line current is then maintained at the minimum required to support instantaneous power flow to the a-c motor so that resonance current is suppressed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.