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SPEED CONTROL OF INDUCTION MOTORS
7.6 CHAPTER SEVEN
FIGURE 7.5 Variable frequency control with a PWM waveform: (a) 60-Hz 120-V PWM waveform;
(b) 30-Hz 120-V PWM waveform.
FIGURE 7.6 Variable voltage control with a PWM waveform: (a) 60-Hz 120-V PWM waveform; (b) 60-Hz
60-V PWM waveform.
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