Research On PWM Speed Regulating Controlled By PLC In The Mining Slope DC Drive Systerm

At present, the world development of mine hoist control system is very mature.But the domestic mines and enhance the development of the control system is still in a backward position. The present mine hoisting system is still using the contact element (relay, contactor) control system, contact elements in the application process has many Shortcomings such like low reliability, high maintenance and high cost. The mine hoist electric drive mostly adopts AC motor rotor series speed, but the speed control mode has some Shortcomings such like small speed range, stable speed difference and a large quantity of equipment maintenance.Based on the1024shaft in a mine of Yunnan, through the analysis of its electric control system and the electric drive system, the author carries on the transformation to the system to improve the1024inclined shaft to meet the mine hoist automation control system. Transformation includes transformation of the speed governing system, the PC monitor interface development and network video monitoring. After the trans-formation of the speed control system of DC motor drive, speed control using PWM pulse DC speed regulation, speed control system after the transformation saves energy consumption and improves the speed stability. System uses two identical PLC redundancy control as main control unit, preparation and finishes the implementation of communication, it ensures the safety of electronic control system. PC monitoring system is developed in the Kingview software environment, communication through PC configuration and PLC, it can display the hoist operation parameters in the development of the interface, which includes the given speed, the actual speed, armature voltage, armature current, hydraulic oil temperature and lifting container depth, in addition to it can show the operation state of the ascension of the whole system and alarm. Network video monitoring transfer the video monitoring points to the control room timely and clearly, let the staff more intuitive, more comprehensive to understand the operation of the state machine. The transformation of the control system to improve the1024inclined shaft reduces the mine operation accident rate and guarantees the safety in production of mine operation work environment. In a word, the above transformation not only ensures the mine equipment and personnel safety, but brings huge economic benefits for the mine enterprises.