基于可编程逻辑控制器的微机调速器测频方法

PLC-based Frequency Measurement Methods for Computer Governor

水轮机调速器性能提高的关键是测频系统,测频精度和实时性是描述测频系统好坏的重要标志。大幅提高水轮机调速器频率测量的可靠性对机组的安全稳定运行起着极大的作用。传统的可编程逻辑控制器(PLC)调速器测频方式由于接口的原因,往往会在精度和实时性上互相矛盾,故PLC测频成为制约调速器发展的瓶颈。针对这种情况,分析了现今比较流行的PLC测频方法,提出了能够保证精度和实时性的PLC测频方法。对基于PLC调速器的直接测周期法以及精度和实时性指标进行了具体分析。

The key to improving the governor＇s performance is the frequency measurement system, and the accuracy and realtime ability are both important symbols to describe the system. Because of the limitation of interface, there is conflict between the accuracy and real-time ability in traditional PLC governor frequency measurement method. Aiming at the problem, a direct cycle-measuring method based on programmable controller computer governor is proposed, and the accuracy and real-time ability are analyzed.