CONTROL CIRCUIT FOR A DIRECT CURRENT/THREE-PHASE CURRENT CONVERTER

摘要

CONTROL CIRCUIT FOR A DIRECT CURRENT/THREE-PHASE CURRENT CONVERTER Control circuit for semiconductor components of a converter circuit which can be switched on and off to convert direct current into three-phase current. The converter circuit is connected between a direct-current source and the stator of a synchronous machine having a cylindrical rotor. The control circuit comprises rotor position sensors and also a direct current measuring device. The control circuit comprises a computer which is designed to determine the value of the commutation angle .mu. of the phase current i in the converter at any value of the direct current Id on the basis of a model of the synchronous machine which solely takes account of the fundamental harmonic of the phase current i, the firing angle .alpha. of the semiconductor components being set between limits determined for any value of the direct current Id by the associated commutation angle .mu..