Small-scale hydropower

A novel harmonics-reducing system of cascaded-induction generators has been proposed, and its effectiveness has been confirmed by the simulation results. Comparing the characteristics of the cascaded generators with those of the single generator, we see that the power efficiency decreases by 1-3%, and the input power factor decreases by around 20%, but the power factor can be improved by controlling the reactive power of the power-recovery inverter. Since the proposed system has the advantages of a low-cost system, a brushless structure, and adjustable-speed characteristics, we anticipate that its use will be practical for small hydroelectric power plants.