Rotation driving system of downhole torque self-balancing drilling tool with cable

The invention provides a rotation driving system of a downhole torque self-balancing drilling tool with a cable, and belongs to the technical field of drilling engineering downhole tools. The rotationdriving system comprises a rotation driving torque motor, a pressure adjusting connecting piece and an inner and outer drill bit connecting assembly, wherein the central axes of the rotation drivingtorque motor, the pressure adjusting connecting piece and the inner and outer drill bit connecting assembly are located on the same axis. The characteristic that an inner rotor and an outer rotor rotate reversely when the common torque motor works is utilized, an inner drill bit torque transmission rod with a sliding key is introduced to change the relative position of driven inner and outer drillbits on the lower portion in the axial direction of a drilling hole, and then the drilling pressure on the drill bits during rock crushing is adjusted, so that the automatic balance of the torque borne by the inner and outer d