20KW Permanent Magnet Generator - Air Cooled or Water Cooled - Rated Frequency 50Hz/60Hz - Suitable for Off Grid Power Systems Product Overview The fundamental concept behind a permanent magnet generator revolves around the rotor containing permanent magnet materials that produce a steady magnetic field. This magnetic field remains constant as a result of the properties of the permanent magnets embedded within the rotor. When a prime mover, which could be a wind turbine,