Control system for AC induction motor
US4425539A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 30, 1982 |
| Grant date | Jan 10, 1984 |
| Priority date | — |
| Expiry date | Apr 30, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P1/44
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A control system is disclosed for connecting the primary windings of a three-phase AC inducton motor in a delta-connection at heavy loads and for automatically reconnecting the windings in a wye-connection at light loads to effect energy savings. Power sensing means produces a control signal which is directly proportional to the power applied to the induction motor. Differential comparator means respond to the control signal and to an adjustable reference signal, representing a preselected power input level, for generating an actuating signal for switching a wye-delta starter between two conditions, one of which effects the wye connection and the other the delta connection. When the power input is below the preselected level the wye-connection is established, whereas the delta-connection is made when the power input is above the preselected level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.