Astoria USES frequencymodulationmotor, belt drive, to achieve a continuously variable.
道夫采用调频电机，齿形带传动，实现了无级变速。
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The automatic production system is computerized by the central computer and frequencymodulation and motor speed change are made by front-end control CARDS.
However, Pulse Width Modulation (PWM) which was input from inverter is characterized by steep rising edge and high frequency, resulting in the too early failure of motor insulation.