PLC与变频器通讯程序可靠性设计

摘要

变频器与PLC之间通讯在工业设备中的应用越来越普遍，工业现场的各种干扰会严重妨碍两者正常的数据通讯，除了硬件设计要考虑抗干扰外，PLC软件程序设计方面更应当考虑可靠性。通过合理的通讯程序设计,包括访问数据的先后次序、定时轮询、随机通讯等软件手段能有效的提高PLC控制系统在干扰环境下与变频器可靠地数据交换。实践结果表明在相同硬件条件下改进通讯程序算法能够有效地改善通讯质量，有较强的实用价值。%Communication between the inverter and PLC becomes more and more common in application of industrial equipment. Various disturbances in industrial site would seriously impede thenormal data communication between the two. In addition to the hardware design should consider outside interference, the PLC software program design should be considered more reliable. Through rational communication program design : including the order of data accessing, timing polling , random communication and other software can effectively improve the reliable data exchange with the inverter when the PLC control system is in a noisy environment. Practical results show that the modified communication algorithm can efficiently improve the quality of communication under the same hardware environment. and has a strong practical value.