Method for the phase-gating control of the voltage half-cycles of a three-phase AC power controller having two current paths, which can be controlled in reverse-parallel, per phase, for a squirrel-cage motor

摘要

In order to operate squirrel-cage motors with a closed stator circuit with graduated operating speeds, z 1 triggerings are carried out successively for half-cycles of the one polarity and half-cycles of the other polarity in the individual phases with phase shifts which are as close as possible to 120 DEG electrical so that f = fN/(2z-1) is produced as the operating frequency, where fN = mains frequency. IMAGE