Abstract : This paper introduces the current development status of grinding mills, elaborates on the design principle, control circuit, and pneumatic control of an electro-pneumatic grinding mill, and provides a detailed analysis of the control part of the electro-pneumatic grinding mill, summarizing the unique operating characteristics of this design. Keywords : Electro-pneumatic grinding mill; frequency converter; displacement sensor 1 Development Status of Grinding Mill Control Systems Electrically controlled pneumatic grinding mills are a replacement and upgrade of all-pneumatic grinding mills. All-pneumatic grinding mills were widely used from the late 1970s to the mid-1990s. The older generation of scientific and technological personnel in China's grain industry devoted arduous labor and unremitting efforts to this. Representative products include the XK2 model from Simon Company in the UK, the FMFQ model in China, and the stress-sealed self-supporting flat grinding roller developed and designed by Zibo Grain Machinery Factory under the guidance of expert Gu Yaochen, all of which are all under all-pneumatic control. With the development of power electronic products and the popularization of industrialization, it has become possible to use some mature power electronic products in the grain machinery industry, and thus, electro-pneumatic grinding mills have replaced traditional all-pneumatic control grinding mills. The essential difference between them is: a fully pneumatically controlled grinding mill changes the opening size of the feeding gate while maintaining a constant feeding roller speed, thus altering the feed layer thickness and ultimately the flow rate; while an electrically controlled pneumatic grinding mill keeps the feeding gate opening size constant while changing the feeding roller speed and feed layer thickness, ultimately changing the flow rate. [b][align=center]For more details, please click: Design of the Control System for an Electrically Controlled Pneumatic Grinding Mill[/align][/b]