Adaptive reference voltage generator for firing angle control of line-commutated inverters

摘要: A control system for a permanent-magnet motor (10) driven by multiphase line-commutated inverter (12) is provided with integrators (24) integrating the back EMF of each phase use in generating signals an gate logic (30) using sync and firing angle (α) generator (26) connected to outputs integrators. precision full-wave rectifier (16) provides speed feedback signal phase-delay (14) via gain loop compensation circuit (20) adaptive attenuation low frequencies as function speed, whereby increases, frequency components increased offset spurious frequencies. The α-control are produced means (48, 50) combining 120° segments integrated symmetrical about their maxima into composite positive negative waveforms, (45, 46) sampling waveform every 120°. These samples then used signals, any change amplitude will not affect operating power factor said inverter.