Method for measuring inherent frequency of stator core/support system of water turbine generator prototype

The invention discloses a method for measuring the inherent frequency of a stator core/support system of a water turbine generator prototype. Through arrangement of an automatic excitation regulator, the terminal voltage of a hydropower unit is kept at a rated value. By setting a given value of the zero load frequency, the method changes the rotational speed of a generator rotor. Thereby the method changes an excitation input of the stator core/support system, i.e. the generator rotor rotation magnetic field force wave rotational speed, and measures a frequency response function of the stator core/support system of the water turbine generator prototype under electromagnetic force excitation of different frequency. According to the frequency response function, a frequency value corresponding to the maximum amplitude can be found, and the frequency value is the inherent frequency of the stator core/support system of the water turbine generator prototype. The method only needs to stop the generator and install a sensor, does not need to apply for heavy maintenance, is simple and convenient in measurement, and thus has a wide application prospect in the field of inherent frequency measurement of stator core/support systems of water turbine generator sets.