1.With speed negative feedback automatically regulated, its speed rate of change: the first step< 1.8% and the second slep<2.5% . 2.Without runaway area of speed with techo generator gauging speed . 3.Stable adjustable operating speed and wide range of adjustable speed . reaching 10:1 4.Good starting performance, smooth start and large moment. 5.Simple reliable structure and convenient maintenance. 6.Small power of controlling speed and easy to control in many ways.
