An extruder drived by a switched reluctance motor  has the following advantages:

(1) The speed of screw with long-term operation can be adjusted from zero to the highest speed in the range of stepless speed regulation, with high efficiency and smaller temperature rise of motor and controller.

(2) When an extruder begins to work, it is not possible to bring about the starting current, which is more than the original rated current 5 to 7 times. Meanwhile, there is no need to start an extruder with lower pressure, for the starting current can be smoothly increased as the current requires. The longer the start-up time is, the smaller the starting current will be. When the starting torque reaches 150% of rated torque, the starting current of the extruder is only 30% of rated current.