The Design Of Control System For Esp Based On PROFIBUS

Dust pollution in the proportion of air pollution increased every year, with not only serious harm to human health, but also result in the loss of a large number of precious materials. A variety of devices are used to control dust particles from dust emissions of air pollution, especially ESP. The applications of fieldbus in industrial what is the latest technology, making the process of industrial automation process control represents a major step, but on the ESP control system is not mature, is a difficult on the ESP technology. As ESP of Qinhuangdao coal Port a example, The station-based interface between ESP and PROFIBUS is designed.According to the main working parameters and indicators of ESP, the control circuit whose core are KC05 and SCR is designed. The adjustment of SCR conduction width is achieved by feedback function of integrated circuit, which is protection circuit of ESP.Operated the controller safely, collecting the voltage and waveform of important node by the oscilloscope. It agreement with the standard waveform nearly, so the controller works properly. The pulse width and SCR conduction angles can be adjusted normally by potentiometer; the warning light is lighted when over-current appeared so that protection circuit works properly. These signals provide a reliable standard for fiedbus communication.The connection between ESP controller and PROFIBUS is achieved by 80C51, SPC3, RS485 and coupler isolation whose key is the connection between 80C51 and SPC3. The operating data on the ESP collected by 80C51 and packaged send to SPC3. Protocol processing of data by SPC3 sent to PC. There is a coupler isolation for eliminating the interference from the zero line. RS485 is half duplex, large capacity drives; so PROFIBUS-DP protocol is usually based on RS485. Program design includes initialization procedure, main loop and Interrupt handler. The communication program is designed between MCU and main station at Software.The design makes ESP as the station of DP bus successfully, achieving the distributed digital control and net communications between the workshop-level and ESP Site, Replacing DCS. It has effective and efficient data transmission. The automation level of ESP is improved by Fildbus and achieving long-distance transmission network. Cable as the main bus instead of a traditional network connection Significant cost savings. It Providing an effective basis for Fildbus application on ESP.