| 摘要 |
A machine drive control system for providing stable motor operation in the presence of a cyclic load, having a current controlled inverter 24, a first control loop 30 for maintaining motor terminal voltage under varying load conditions, and a second control loop 58 for stabilizing motor frequency against hunting oscillations. A waveform generator 10 produces three sinusoidal reference signals in three-phase relationship. These signals are compared with feedback current signals from the motor phases, and PWM control signals are supplied to the inverter 24. The loop 30 responds to motor flux determined from phase voltage measurements and a flux command signal psi * to produce amplitude commands for waveform generator 10. Loop 58 responds to phase current supplied by a synchronous switch 62 and an amplifier 70 responsive to transient changes to determine the frequency commands for generator 10. <IMAGE> |
