Novel class dynamoelectric machines utilizing “tangential induction” phenomenon—the specific e.m.f. induction, which appears in tangential conductors—is introduced. Alternating-current dynamoelectric machines of this invention house an axially-polarized multi-polar permanent magnet rotor and stator winding having tangentially arranged semi-ring conductors. The rotating permanent-magnet rotor induces current in tangential semi-ring conductors, which, according to Ampere law, could not produce a resistance moment applied to the rotor because the vector of conductor-field velocity is directed along the conductor, and, therefore, such vector orientation does not produce any tangential force. The invention has been successfully embodied in number of “tangential-induction dynamoelectric machines” including multi-phase ones. These dynamoelectric machines can be inverted and work as alternating-current asynchronic electric motors.