The Design Of Frequency PLC Control System For Rail Coarse Grinding Machine

Railway transportation is the main way of logistics currently in China, with the rapid development of railway transportation to the direction of large tonnage and high speed. High-speed passenger railway and Heavy cargo railway are the two major trends of railway development all around the world. High-speed railway calls for track with high ride and high stability, the advantages of the seamless rail have been increasingly recognized by most people, and it has become an important symbol of railway modernization in all the countries. China’s main methods of railway rail welding involve aluminum heat welding, gas pressure welding and flash butt welding. The seamless rail line is constituted by tracks of about500m long, which consists of20short tracks of25m modeled for60kg/m welded together by continuous flash butt contact welding without preheating. But rail welding joint is the weak link of seamless rail line, in order to ensure the safety of seamless rail line’s high-speed operation, it is necessary to take preventive grinding after the rails are welded. Therefore, the independent research and development of the rail coarse grinding machine is of great significance.According to the problem in reverse and speed control of the top grinder in the process of profile grinding in original control system of the rail coarse grinding machine, this paper mainly researches and designs a frequency PLC control system for rail coarse grinding machine based on PLC and frequency inverter. The paper focuses on the design method and process of communication between the Mitsubishi FX2N series PLC and the Mitsubishi inverter FR-E540based on RS-485communication module, including the hardware connection and communication protocol settings, and inverter parameter settings, and provides corresponding program codes, the supervisory system with touch-screen can well satisfy various control and communication needs. Practice shows that this improved system overcomes the shortcomings of the above grinding of the rail coarse grinding machine effectively and also has reliable running, which has good prospects for industrial applications.The method of PLC controlling frequency inverter using RS-485communication mode can not only complete all the traditional applications of frequency inverter, such as start, stop, frequency setting, but also the internal data communication which can easily access a variety of motor parameters from the driving frequency inverter, such as operating frequency, operating current, operating voltage, operating power and so on, connected through a single communication cable with no other external wiring. It’s convenient and simple for the inverter parameter setting and monitoring using the touch screen. The system has the following advantages:the hardware is simple, low cost, and the system can control up to32inverters, can achieve stepless speed regulation smoothly and precise speed control, It’s adaptable, it has long distance signal transmission and strong anti-interference.