Direct electric energy conversion without input power regulating system or gearboxes may offer a simpler and thus low cost way of converting the energy of moving water. The proposed electrical system consists of a permanent magnetized direct drive generator, a rectification step, transmission, an inverter, a transformer, and a grid connection. This paper focuses on the generator, and simulations of a 5 kW permanent magnetized direct drive generator have been performed. Operation of the generator at both part load and overloads are calculated and presented. It is found that this direct drive permanent magnetized generator provides a relatively high efficiency for both part load and overload conditions.
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