Automatic calibration of field-oriented elevator motor drive parameters using standstill motor measurements
US5883344A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1997 |
| Grant date | Mar 16, 1999 |
| Priority date | — |
| Expiry date | Dec 22, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H9/0595
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An elevator controller 7 is provided with logic 48 which automatically calculates a motor time constant (.tau..sub.R), a torque constant (K.sub.T *), and a magnetizing current (Id) for a field-oriented motor/drive system by calculating a transient inductance L.sigma., injecting a variable input frequency sinewave into a q-axis reference current I.sub.qREF and varying the input frequency while calculating an imaginary part of a rotor impedance Imag(Z.sub.R) to obtain a frequency (F.sub.PEAK) at which the maximum value of Imag(Z.sub.R) occurs, then calculating .tau..sub.R from F.sub.PEAK. K.sub.T *, Id, and a total motor voltage V.sub.M are calculated and Id is varied until a ratio of rated motor voltage (Vph.sub.-- RATED) to V.sub.M is within a predetermined tolerance of one. The procedure is performed with the rotor locked.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.