In order to solve the problems that the magnetomotive force angles of parallel branches of each phase are different in the rotor single pole-changing equal-turn winding scheme of the brushless doubly-fed generator, and the current amplitudes of rotor winding branches are different resulting in the percentages of the magnetomotive force changing with the load and the reduction of the wire utilization, the unequal-turn design scheme and improved scheme for reversing all the coils of the three self-shorted branches to the corresponding connecting line are proposed. The generator operating characteristics of equal-turn, unequal-turn and improved scheme are simulated based on the finite element. Results show that the unequal-turn scheme reduces the harmonic contents, cuts down the difference among the current amplitudes of parallel branches and improves the waveform quality. In the improved scheme, the rotor branches waveforms quality is good, the current amplitudes are equal, the wire utilization rates are improved, the harmonic contents are furtherly reduced, and the magnetomotive force are fixed, which is easy for the generator control.