最后针对某典型工程应用系统—基于PROFIBUS现场总线和PLC的VD精炼炉分散控制系统，考虑了主站plc的延迟，分析了其PROFIBUS现场总线的实时性能。

Finally, for the typical project of VD refining furnace which is based on PROFIBUS and PLC, with consideration of PLC scanning time delay, the real-time performance of PROFIBUS is analyzed.

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