The invention relates to a parallel structural hybrid excitation synchronous generator without an electrical excitation rotor, comprising a permanent magnet motor (17) and an electrical excitation part (18) which are coaxially arranged in a case (13) in parallel, wherein the two parts of magnetic circuits are independent; an armature winding (5) is respectively arranged in stator cores of the two parts, and another three-phase or multiphase excitation winding (10) is arranged in the electrical excitation stator core (12); a magnetic conductive ring (11) is arranged at the inner circle of the electrical excitation stator core (12) to provide a pathway for an electrical excitation magnetic field and an armature magnetic field; and the size and the phase of current in the excitation winding (10) are changed through a frequency converter to adjust the size and the phase of the electrical excitation electromotive force in the armature winding (5), thereby reaching the purpose of changing the output voltage size. Because the electrical excitation part has no air gap, the required magnetic motive force of the electrical excitation is little and the adjusting efficiency of the magnetic field is high. Irreversible demagnetization to a permanent magnet cannot be caused by the electrical excitation magnetic motive force; and the reliability of the motor is high by utilizing brushless alternating current excitation.