Stator Teeth Model for Optimum Flat Linear Permanent Magnet Generators

Direct-drive wave energy converter (WEC) with linear permanent magnet generators (LPMG) has been recognized as an efficient system to convert wave energy to electrical energy. However, it suffers from a significant cogging force during its translator movement. Any attempts to reduce the force should also consider the effects on the electrical output as well as the overall dimension. As teeth salient ends affect the magnetic flux flow, its configuration can impact the cogging force but also induced voltage. Hence, this paper presents several design alternatives of teeth salient ends' shape to achieve optimum cogging force and output voltage without changing the overall size. The voltage and cogging force from different models are extracted by using finite element magnetic-based simulation and analytical calculation. The results show that flat, outward-trapezoid, and outward-quarter rounded salient end models bring the optimum induced voltage and cogging force.