Robotic placement of high-strength permanent magnets for a wind turbine generator

We report a novel method for automating the placement of suface-mounted permanent magnets within electrical machine rotors. This process was part of the manufacture of a generator being developed for offshore wind turbines. Magnetic forces during placement were predicted to exceed 5 kN, which would exceed the payload of all but the largest industrial robots. A robot end-effector was designed and manufactured to overcome these magnetic forces. Its design incorporated structural elements that interfaced with the steel hub, thus isolating the robot from the forces. Instead of requiring a large robot to resist the magnetic forces, this end effector allows the process be carried out by any robot capable of lifting the end effector and magnet. In addition, the automated solution allowed the process time to be reduced from 55 minutes per magnet to 55 seconds, with scope to reduce this further in the future.