PLC在SLon系列磁选机的应用

摘要

Magnetic Separator has been widely used in metallurgical industries, such as dressing, impurities removal. Manual control was traditionally applied to operate magnetic separator. It needs human intervening on the spot, which cannot reflect the recycling level and other issues adequately. We design a new type of magnetic separator in order to adapt to the development of magnetic separation technology. The controlling system of Slon Magnetic Separator uses Siemens S7-200PLC and TP170B touch-screen. Excitation current as the main control parameter adopts PID-control to achieve optimal control of magnetic separator system. This system converts the temperature of SCR components, excitation voltage and current to voltage (0-5 V) or current (4-20 mA) and sends them to PLC by the temperature transmitter, current transmitter and voltage transmitter. These signals output through the digital module and Analog Output module, which are used to Control the high-grade or low-grade of fan and angle of the trigger flip-flop. In this way, SCR can work in the allowed temperature conditions and excitation current stability in the settings. All these make the system working smoothly.%SLon系列磁选机是运用开发细粒弱磁性矿物选矿新技术而研制的高梯度先进磁选设备。采用基于西门子公司的S7-200 PLC和Smart 700 IE触摸屏控制结构设计的SLon磁选机控制系统，对主要控制参数-励磁电流采用PID控制算法，实现对磁选机系统的最优控制。该控制系统通过温度变送器、电流变送器、电压变送器将可控硅元件的温度、励磁电流和电压转换成0-5 V的电压或4-20 mA的电流送入PLC的控制器模块，通过设计PID控制算法，控制可控硅数字触发装置，精确地调整可控硅触发时的开通角，使可控硅元件工作在允许的温度条件下，输出稳定的励磁电流。