Reform Of Electric Control System Of Mine Hoister Based On PLC

The shaft hoist has been used to transport coal, coal gangue, materials, equipment, personnel and connect the entrance and the bottom of the mine together, is an important guarantee for the efficient and safe production of a coal mine.Restricted by the development of components, the traditional hoist electrical control system with relay-contactor control technology has many disadvantages such as complex hardware circuit, poor reliability,high failure rate and large energy consumption, which can not meet the high efficiency and energy saving control requirements of modern enterprises.therefore, the renovation of the control system has a positive significance.In order to solve the problem of the shaft hoist electrical control system in the coal mine of Wang-Shiwa which obtains the traditional relay-contactor control,the author put forward a new renovation scheme.programmable logical controller,computer and High voltage frequency converter are applied into the control system for the mine hoist and a feasibility study about the renovation scheme has been done. The programmable logic controller is the core of the control system which does the hoisting machine logic control in all stages of operation, improve the system reliability, meet the requirement of ascension process, and simplify the hardware circuit;The computer as the upper machine, monitor the entire online hoist running process, realize the running state and running parameters monitor and data query, fault diagnosis and query report printing,etc;High Voltage Viable Frequency Viable Speed technology(VFVS) are applied as the electric drive unit which can realize smoothly speed regulation, large speed regulation range, high speed regulation precision and significant power-saving.Comparing to the speed regulating method of series-connecting the additional resistant in rotor circuit, the new method can save energy 20% to 40%.After implementing the renovation in the electrical control system of a shaft hoist in the mine of Wang-Shiwa, more stable running status, convenient operation, safety and reliability, remarkable energy saving effect can be achieved.