Load-adaptive smooth startup method for sensorless field-oriented control of permanent magnet synchronous motors
US9998044B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 16, 2016 |
| Grant date | Jun 12, 2018 |
| Priority date | — |
| Expiry date | May 30, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P21/34
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A field oriented control (FOC) system and method provides smooth field-oriented startup for three-phase sensorless permanent magnet synchronous motors (PMSMs) despite the absence of load information. The system uses the rotor flux projection on the d- or q-axis to determine whether the stator flux current reference being applied during reference startup phase is sufficient to spin the PMSM, thereby providing smooth operation during the reference startup phase and saving energy relative to applying rated current. The system also determines a suitable initial value for the stator torque current reference to use at the start of closed-loop sensorless FOC control mode based on an angle difference between the reference and estimated angles. Since this angle difference is reflective of the load on the PMSM, the selected initial value allows the system to achieve a smooth transition from reference startup mode to closed-loop sensorless FOC control mode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.