PLC在空压机变频调速系统中的应用

Application of PLC in the Variable Frequency Control System of Air Compressor Units

本文介绍了使用PLC、变频调速技术对某空压机组继电器控制系统改造的设计和应用,包括电气控制系统的硬件设计、程序设计及人机界面设计等。西门子S7-200 PLC。通过MOD-BUS通信可以控制ABB公司变频器ACS800的启停、给定参考速度,并可以实时读取变频器的主要运行参数。通过现场传感器采集的测量信号可进行模拟量闭环的PID调节,实现高精度的空压机组恒压供气运行,很好地满足了大型用电设备对节能降耗的要求。

By analyzing the technology transform demands and control principle of the air compressor units, a detailed control design of air compressor units system based on Siemens S7 - 200 PLC, ACSS00 inverter hnd MODBUS communication is introduced, including hardware design, program design, and communication realization, and etc. Through MODBUS communication the high power inverter operation can be controlled by the PLC. Meanwhile, the main running parameters of the inverter can be read back to PLC. The automatic analog adjusts of the whole process of air pressure by close - loops PID are realized, and the object of energy saving can be definitely achieved.