Method of estimating a rotor position of synchronous motor, method of controlling synchronous motor with no position sensor and a controller of synchronous motor
US6396229B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 2000 |
| Grant date | May 28, 2002 |
| Priority date | — |
| Expiry date | Sep 1, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P2207/05
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a method of accurately estimating the rotor position of a synchronous motor having saliency from observable quantities, a control system for adjusting an output frequency of an inverter on the basis of a value of axis shift of the synchronous motor to operate the motor synchronously with the output frequency is provided with an induced voltage estimating/axis shift operating unit. Currents resulting from conversion of detection currents on a control axis, voltage commands to be inputted to an inverse converter and a speed command are inputted to the operating unit to estimate an induced voltage of the motor 2 and determine the axis shift from a phase of the estimated induced voltage. By using an electrical constant Lq of inductance, a voltage drop across the inductance is determined by the product of a motor speed command and magnitude of motor current. The voltage drop is a virtual quantity that does not depend on the motor rotor position. A vector of the virtual quantity is so introduced as not to change a phase of the original induced voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.