Inverter control apparatus using a two-phase modulation method
US5650708A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 10, 1995 |
| Grant date | Jul 22, 1997 |
| Priority date | — |
| Expiry date | Mar 10, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/70
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An inverter control apparatus for driving a polyphase AC motor for preventing abrupt changes in motor drive currents when switching of one phase is stopped. The apparatus includes a signal generator for generating duty signals of drive signals of respective phases on the basis of a generated reference waveform and a signal modifier for selecting one of the duty signals of one phase, holding it at a predetermined level, and modifying the duty signals of other phases according to the value required to hold the selected duty signal. On the basis of three-phase signal voltage levels, a decision is made on voltage fixing phase intervals by a phase decision circuit, and shift values are determined by an adder at every voltage fixing phase interval. Shift values are selected by a multiplexer according to the outputs of the phase decision circuit and added to triangular wave voltage. Resultant sum values are compared with the three-phase signal voltages to form a three-phase PWM signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.