核电厂半速发电机传感器支架共振解决方法研究

Study on Solutions to Sensor Support Setting Resonance of Nuclear Power Half-Speed Turbo-Generator

测点支架的一阶固有频率接近发电机工频的4次谐波,造成支架共振,是导致在线振动测量值高的原因。利用三维立体建模软件对振动传感器的支架进行建模,并用有限元分析软件对其进行频率特性分析和计算,通过增加质量块和增加刚度两种解决方法,改变振动传感器支架的固有频率,可避免共振。

The root cause of the high on-line vibration measurement of the nuclear power half-speed turbo-generator is studied, and the result shows that the first natural frequency of the sensor support setting isclose to the forth times harmonic wave of the generator speed frequency, that is the root reason of the high on-line vibration. This paper uses the three-dimension modeling software to make fixture mode of the sensor support setting, and utilize finite element analysis（FEA） software to analyze and calculate its frequncy characteristics. Two schemes are offered by adding a mass block or increasing the stiffness of the sensor support setting, that change the natural frequency. So the resonance is avoided, and the authenticity and effectiveness of the on-line vibration is ensured.