Abstract: A monitoring system for mine main fan is designed and built in Xudong Coal mine. This paper introduces the working principle of the monitoring system based on PLC controller and inverter control technology. This paper analyzes the problems in the design and construction of the monitoring system from the aspects of the main equipment composition, principle and structure, as well as the basic principles. This paper makes an in-depth analysis of the problem of non-stop wind switching in the actual demands, and introduces in detail the solution of the starting and stopping curve of the inverter in conjunction with the control of the butterfly valve, and implements it.