Research Of Coal Mine Wind Rate Regulation System Based On Fuzzy PID Control

The coal is playing a vital role in the national economic in the basal energy source of our country, which occupies over 70% energy sources consumption. Ventilation is the most important part in the process of the coal mine exploitation, it can reduce the gas density of mine effectively and avoiding the gas accidents' occurrence, but ventilation is a complex process and it consumes electricity. The working status of ventilation system influences the production efficiency and safety. In order to save energy, the ventilation system must be keeped run with safety and high efficiency automatically.Coal mine wind rate regulation system based on fuzzy PID control has been presented in the paper with PWM output and implementing it with PLC under the circumstance of many influence factors, which exist in the axial-flow fan's wind rate regulation system during the process of mine ventilation and are difficult to establish the mathematic model to obtain the satisfied result in normal control ways.The structure of wind rate regulation system based on fuzzy PID control mainly includes adjustable PID and fuzzy control system. The wind rate regulation is realized by adjusting the angle of the ventilator's vane controlled by synchronization electromotor. The system uses two dimension fuzzy controller which has two input value and one output. One input is wind rate error, which is the margin between the given value and feedback value. The other input is the wind rate error's change rate; the output is a control quantity and is used to control the air blower wind leaf angle.For the difficulty of PID controller parameter's adjusting, the combination of PID control and fuzzy control was put forward and a fuzzy self-adjusting PID controller has been built. Through the rules of fuzzy control the three parameters of PID controller can be adjusted adaptively on line. Then the computer simulation method of this controller was described with detail. The results of simulation show that the fuzzy self-adjusting PID controller has good dynamic response curvy short response time small over modulation high steady state precision good dynamic and static performance by comparing with the traditional PID controller.The experiment has proved that the control system with fuzzy PID control strategy does not need the precise mathematical model of the controlled model and can operate with stabilization, high reliability and has good flexibility and operational capability and high robustness in the value of wind regulating controlling system with the big lag, the indefinite parameter or great inertia. At the same time, the method has very good reference value for these control questions with big lags, instable characteristic parameters.