介绍了清华大学热能工程系动力工程及控制实验室研制的ＤＫ－ⅡＡ型扭振监测系统，主要用于大型汽轮发电机组轴系扭振的监测。该系统采用“脉冲时序法”的原理，在齿形盘附近安装非接触式传感器。在传感器信号进入计算机之前，采用了一种独特的数字化处理方法，没有采用Ａ／Ｄ转换器，从而提高了测量精度。系统的测角分辨率为０．００１８°，精度可达０．０１°，而且成本较低。该系统已安装在宁夏大武口发电厂并用于扭振的实时监测 The DK-ⅡA torsional vibration monitoring system developed by Power Engineering and Control Laboratory of Tsinghua University is mainly used for the monitoring of torsional vibration of large turbo-generator shaft. The system uses the “pulse timing method” principle, in the vicinity of the toothed disk to install non-contact sensor. Before the sensor signal into the computer, using a unique digital processing method, do not use A / D converter, thereby improving the measurement accuracy. System angular resolution of 0.0018 °, accuracy up to 0.01 °, and the cost is lower. The system has been installed in Ningxia Dawukou power plant and used for real-time monitoring of torsional vibration