The Research And Design Of Multi-loop Mine Combination Switch Based On PLC

During the 13th five-year,the state adopts the supply-side structure reforming,to make the growth steady and adjust the structure and promote the reformation.The state also shuts down many small and medium coal mine, only keep the higher yield of large coal mines in order to eliminate the backward production capacity of coal.For centralized mining of coal, all kinds of mining equipment such as stage machine, crusher, conveyor and so on are relatively concentrated,and the control of this size of combination switch capacity, control and the safety of the control system are putting forward higher requirements. Currently on the market most combination switch's capacity are small,and only can control less circuit, so researching the large capacity and can start more branches combination switch at the same time, has the very vital significance.With XGT series PLC as the control center,a set of fourteen of intelligent mine combination switch circuit is designed,with the function of 14 sets of 2400kW and below the capacity of three phase AC induction motor starting and stoping.This combination switch can achieve a single independent operation,dual-speed two-speed linkage operation,stand-alone two-speed operation and multiple program control operation and other flexible diverse operation.In this thesis the control center module of the combination switch is selected and designed according to the system design requirments,include power control module and input and output module and communication module and so on.Then analyzes the three common faults of combination switch, for different fault their corresponding protection algorithm are proposed: the leakage fault uses additional DC power supply protection algorithm,and the current fault uses the inverse time characteristic protection algorithm,and the transient overvoltage fault uses the pressure sensitive resistance and resistance capacity to absorb the protection method of combining. In order to facilitate the staff to set the system parameter,and to have a more intuitive understanding of the system running situation, this thesis also uses XGT series configuration software XP-Builder to design a set of beautiful and simple man-machine interface, including normal operation when the display screen and parameter setting interface and combination control interface and fault alarm when the floating window.Due to the coal mine special working environment, can't display operation directly, therefore, for the man-machine interface system to add the keyboard module, the keyboard is added to achieve to the operation of the screen.Cooperating with the design of the hardware system and human-machine interface,writes a set of software program with the function of control, protection, monitoring,display,and draws the corresponding program flow chart.Finally, the whole machine commissioning shows that the design of the multi-loop combination switch can not only complete the operation of the normal control,but also ensure the safety of the system in the event of a failure action in time.