Mixed-excitation-type impeller generator for petroleum drilling

The invention provides a mixed-excitation-type impeller generator for petroleum drilling. The impeller generator consists of two parts, namely an impeller assembly and a generator assembly. The impeller assembly consists of an impeller and an impeller shaft; the impeller shaft is connected with a generator rotating shaft assembly through a gear reducer; the generator assembly comprises an upper bearing assembly of the generator, a generator rotating shaft assembly, a generator room, an upper generator stator assembly, a lower generator stator assembly and a lower bearing assembly of the generator; and the generator rotating shaft assembly comprises upper and lower groups of permanent magnets and salient pole groups, which respectively and axially correspond to the upper generator stator assembly and the lower generator stator assembly which are located at the outer side of the generator rotating shaft assembly. According to the impeller generator, not only can the reliability of rotary sealing be assured, and