Method and apparatus for correction of the flux direction of the modelled flux in a field-oriented rotating field-machine without any sensors, down to zero frequency
US5936377A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 1998 |
| Grant date | Aug 10, 1999 |
| Priority date | — |
| Expiry date | Jun 30, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P21/141
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method for correcting of the flux direction of a modelled flux vector down to zero frequency. The modelled flux vector is formed by a machine model as a function of a stator current vector and a stator voltage vector of a rotating-filed machine that has no sensors. A nominal (command) value for the field-forming (field-producing) and torque-forming current (torque-producing) component of the stator current vector of the rotating-field machine is determined. A current test vector is then added to the nominal (command) value of the field-forming (field-producing) current component. The current test vector has a profile that is non-constant with respect to time. The rotating-filed machine is driven into the saturation region, and the determined voltage vector of the rotating-filed machine is used to recover the response information of the rotor current vector, to which the test movement of the stator current vector is transferred. Thus, the inaccuracy of the so-called voltage model at low frequencies is corrected down to zero frequency, without interfering with the rotating filed machine.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.