Nanjing Rubber & Plastics Machinery Plant

Over the years, it is a problem for stepless speed regulation in maintaining a large screw extruder torque, due to direction changing of DC motor for speed control, small torque of AC motor, and complex mechanical of speed control, continuously variable high cost and low efficiency of the hydraulic motor, along which many new ways come into being. There are many shortcomings of VVVF, such as low speed electric heat, large energy consumption, low efficiency, torque small, narrow speed range, and the phenomenon of electrical burn, reliability and low running so that people are unsatisfied with VVVF of screw extruder.