Those operating states include the over-excited phase-lag operating state of the synchronous generator,the normal excited same-phase operating state of the synchronous generator,the lack-excited phase-advanced operating point of the synchronous generator,the zero load operating point of the synchronous generator,the lack-excited phase-.

Simulation of dynamic processes for hydro-generator and turbine-generator under loss of excitation and self-excitation;

Low potential is one of the most important characters while the generator is in loss of excitation process.

It is concluded that the arc on the burned out positive wire of the rotor led to the loss of excitation, and the lack of over-excitation protection, etc.

Simulation on external short-circuit and excitation-loss failures of generator;

Taking one magnetism loss breakdown of No.

It intraduces 10·23 accident in Yangguang power company,emphasize on cause of differential and magnetism loss protective action on main excitation machine and present measures of technical reform.

Comparison of the two criteria of rotor low voltage in the generator loss-of-field protection;

05I gn as the setting of the single element transverse differential protection, which is recommended in the guide rule, the maloperation has happened during a complete loss-of-field fault in the Ertan Plant, so an increase of 10% on the .