Abstract:A principle of speed control with frequency conversion technology has been introduced in this paper as well as an application of PLC closed-loop control in frequency conversion.During the past decades,closed-loop control has gained further development.At this stage,fuzzy self-tuning PID control in the frequency has made a significant optimization,Based on this core,a network system which aims to realize the coal mine ventilation technology of energy efficient has been constructed:one kind of wireless sensor as the main component of the perception layer ,the network layer based on the IPv6/Zigbee network protocols and the application layer.