Based on analysis and discussion to normal design of frequency speed change control for cement plant, optimized design plan for general frequency speed change control has been put forward.

They work with remote control devices that change the direction, position and speed of a German-made cutting machine that slices back and forth along a 300-metre-wide coal face.

Step motor control, by pulse by changing the order of electricity can change the motor rotation direction, change the pulse frequency can change the motor rotation speed.