Automatic control systems are control systems that allow a production process or other process to be carried out in accordance with a desired or predetermined procedure without the direct involvement of an unmanned person. Automatic control systems are the primary means of achieving automation. Referred to as the automatic control system. With the increasing competition in the manufacturing industry of industrial automatic control system devices, large-scale industrial automatic control system device manufacturing mergers and acquisitions and capital operations are becoming more frequent. Domestic excellent industrial automatic control system device manufacturers are paying more and more attention to the research of the industry market. In particular, in-depth research on the industrial development environment and product buyers. It mainly introduces the basic contents of the automatic control principle required by the electric drive control system, the analysis and correction of the automatic control system, the closed-loop DC speed control system, the reversible DC speed control system, the DC pulse width speed control system, and the position following system. New technologies such as variable frequency speed regulation and vector control in AC speed control system, combined with engineering practice, introduce the use technology of frequency converter.