| Mineral ventilation system plays an important part in mineral yield safety. The research and application on the automatic monitor and intelligent control will improve the dependability and power-saving of the system. The research of this paper is base on the project of the digital alteration in the Shandong Sanhekou Mining Co.,Ltd. The main purpose is to design an automatic mineral ventilator monitor & power-saving system, which has two main functions. First, it can monitor remotely the mineral ventilator online and receive the value of temperature, pressure and air rat of ventilation by PLC, achieve the automatic monitors of the whole ventilation system. Second, on the foundation of the monitor system, by utilizing the newly AC transmitting technology, the system can adjust the speed of motor's rotor and air rate of ventilator, completely change the existing method of air rate control then achieve power-saving and high efficiency.On base of above research, the following work focuses on the vector control of AC governor, which is one of the technologies about adjusting speed with variable frequency. Aim at the three-phase squirrel-cage asynchronous motor in mineral ventilation, this paper resolves the math equations of motor, decouple the torque with vector theory and provide it an excellent preferment.Three-phase asynchronous motor is the final control object of vector control. By analyzing of Sinusoidal Pulse Width Modulation (SPWM), the vector control is realized with three-phase converter, which is combined with non-controlled rectifier, and SPWM inverter.Variable structure control with sliding mode is proposed to improve the robustness of vector control system. A rotor speed regulator with sliding mode technique is designed and optimized in the aspect of both response acceleration and chatting reducing. The simulating results show that the vector control system of the AC motor with the slide mode speed regulator has a favorable performance.
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