Hybrid field generator controller for optimised performance

Wind turbines have become widely used in the generation of electricity for battery charging. The means of voltage control is provided by power electronics. The charging voltage is maintained at 28 V throughout the generator speed range between 149 rpm and 598 rpm. Using a DC-to-AC power inverter and an AC-to-DC power converter to vary the generator excitation level does this. Varying the excitation level varies the generator air gap flux density during three modes of operation: buck, boost, and permanent magnet modes. This paper describes the controller power electronics control circuit design techniques. It also analyses of the generator armature excitation tests results and the operation of control signals.