Abstract: A generator or a 3-phase motor is arranged to provide multipolar permanent magnet excitation in combination with multipolar reluctance distribution wherein different numbers of poles are used for the permanent magnet excitation and for the reluctance distribution so that the principal working flux has a finite waveform. An annular rotor rotates about a cruciform stator. The magnets are buried in pole pieces of the stator so they converge radially inwardly with a triangular pole piece between them. Each pole piece is joined to the remainder of the stator by a bridge piece. The inner periphery of the rotor is formed as a circumferential array of teeth separated by recesses. The rotor may be within an annular stator or the machine may be linear.