The invention provides a high-reliability dual-channel servo motor of a light automobile. The high-reliability dual-channel servo motor comprises a rotor core, main armature windings, additional armature windings, a rotating shaft, permanent magnets and a stator core. The number of armature grooves is 18, the armature grooves comprise 12 large armature grooves and 6 small armature grooves, and theincluded angle between the center lines of every two adjacent large armature grooves is 30 degrees. The armature windings on the armature poles are divided into the main armature winding and the additional armature windings, and the turn ratio of the main armature windings to the additional armature windings is preferably 0.8: 0.2. According to the high-reliability double-channel servo motor of the light automobile, a phase-A armature winding, a phase-B armature winding and a phase-C armature winding form a first channel, and a phase-X armature winding, a phase-Y armature winding and a phase-Z armature winding form a second channel. The phase difference between the phase A and the phase X is 30 degrees, the phase difference between the phase B and the phase Y is 30 degrees, and the phasedifference between the phase C and the phase Z is 30 degrees. Compared with a traditional servo motor, the torque ripple of the servo motor is reduced by adopting a winding mode combining the long distance of the main armature windings and the short distance of the additional armature windings.