| 摘要 |
A wind powered display comprises a wind turbine / windmill wherein a plurality of LEDs 3 are incorporated along the length of one or more of the blades 1. An electrical generator 2 is coupled to the turbine. The LEDs are controlled so that as the blades rotate they form an image by persistence of vision effect. A microcontroller and memory means 14 are provided to store operational algorithms and program data controlling the displayed image. A closed loop adaptive control allows the power consumed by the display from the generator to be adapted in order to maintain a high rotational blade velocity of the generator at lower wind speeds. The image and the number of powered LEDs may be controlled with regard to the generator braking current. A resistive ballast load or high capacity battery may be provided to increase generator braking and prevent the blades from spinning too fast in high winds. Brightness control means may be provided to maintain a uniformly illuminated image by more brightly illuminating LEDs that are further from the hub, and hence travelling faster, than those closer to the hub. A bi-directional communication link, e.g. via IR, RF, network or Internet, may be provided to allow the uploading of display information and control algorithms to the memory. A balancing weight 13 map be provided to balance the blades. |
