As a manufacturer specializing in the production and sales of generator sets, Jiangsu Haixing Power has been committed to the generator set industry for decades and can be called an 'old Chinese medicine doctor' in terms of technology. I heard from customers showing excitation generator sets experiencing demagnetization symptoms during regular use. , after pulse diagnosis by Haixing Generator Unit, the details of the medical record are as follows: Symptoms: The reactive power meter indicates reversely, the stator current swings periodically, the active load is slightly lower, the stator voltage decreases, and the rotor voltage and current have different indications according to different fault points. When the rotor circuit is disconnected, the voltage rises and the current is zero; The excitation circuit or armature circuit of the exciter is disconnected, and the voltage and current are close to zero. In a demagnetized generator, the rotor magnetic field disappears and the electromagnetic torque decreases, while the prime mover torque remains unchanged. Therefore, the unit speed increases, and the rotor and stator magnetic fields have relative speeds, that is, slip occurs between them and they are out of synchronization. There is slip between the rotor and the stator, and the generator produces asynchronous torque, which is balanced with the torque of the prime mover.