Abstract: Based on the introduction of the working process of air compressor, this paper illustrates a controlling system centering on programmable inverter. This controlling system, adopting a closed loop composed of programmable controller, inverter, sensor and object as hardware, and PID adjustment as software, stabilizes the air feed system by adjusting the programmable and inverter parameters based on the real-time surveying data. This controlling system realizes the energy saving effect of air compressor by improving the stability of air feed pressure.