Abstract: A rotor has outside conductors and inside conductors. The outside conductors are connected together at spaced connection points to form an outside loop which is preferably triangular. Each inside conductor has an outer end connected to one of the connection points, and an inner end provided with an output electrical connection. Each outside conductor and the inside conductors connected to its connection points form an inside loop that occupies only a portion of the rotor's circumference. The rotor lies in oppositely oriented magnetic fields which are disposed so that the total magnetic flux through all of the inside conductors varies during rotation, and the total magnetic flux across the outside loop is zero at all times during rotation.