Device for controlling induction motor and method of controlling the same
US6147470A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 1999 |
| Grant date | Nov 14, 2000 |
| Priority date | — |
| Expiry date | Mar 12, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P21/36
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A vector control apparatus having a DC braking function which is insusceptible to trip even upon DC braking and scarcely suffers vibration upon stoppage is provided. The control apparatus includes a DC braking control arithmetic unit 1 and switches S1, S3 and S4 controlled thereby, wherein in a vector control mode, the DC braking control arithmetic unit 1 sets all the switches S1, S3 and S4 to position a for realizing the vector control. When a DC control state is to be validated from the above-mentioned state, phase of voltage vector is calculated to change over the switches S1 and S3 to position b, and the absolute value of the q-axis current is compared with a reference value .alpha.. When the absolute value of the q-axis current is smaller than the reference value .alpha., the switch S4 is changed over to the position b to thereby effectuate only the d-axis current control. According to the present invention, there is provided a vector control apparatus having a tripless DC braking function. Since vibration occurring upon stoppage can be suppressed, stopping position accuracy upon DC braking in emergency can be enhanced. Further, low-noise systems are made available.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.