Abstract: In order to study the transmission characteristics of a new-type axial asynchronous permanent magnet coupling with 18 poles and 16 slots, the theoretical calculation method of the torque is obtained by theory of layered model firstly; then the distribution of 3D transient air gap field and the influence of different working parameters on torque characteristics are obtained; lastly, the 3D air gap field and torque in different working conditions are measured by the measure system of three-dimensional magnetic field and magnetic drive experimental platform, and the relationship curves between different working parameters and torque or efficiency are achieved. The results of simulation and experiment show that: the maximum magnetic flux density occurs at the magnetrotor, the magnetic flux density of the yoke iron attached to magnetic poles is also large; the axial flux density is the main component of air gap flux density; the axial flux density and the torque increase when the air gap thickness decreases；while the slip ratio and input speed increase respectively, the torque increases but the axial flux density decreases; the slip ratio increases slightly in a linear way firstly and then quickly with the increasing of the output torque, while the transmission efficiency firstly increases but then decreases slightly, particularly，at the 3% slip ratio the efficiency is up to the maximum; under the given 6% slip ratio the efficiency almost keeps about 94% when the input power increases, which verifies the law that the summation of slip and efficiency is constant 1; the efficiency keeps about 95% and the slip ratio is between 2% to 6% when the torque is between 26 and 48 N•m, by which excellent transmission characteristics and high efficiency could be proved in the heavy load working condition.

Key words: axial asynchronous permanent magnet coupling;torque characteristic;air gap magnetic field;efficiency;3D;magnetic field