The invention provides a
water flow power generating device, which comprises an installing platform, a rotating mechanism, a
tower tube, a
machine cabin, a power generator, a gearbox and an
impeller, wherein the installing platform is positioned on the water surface, the rotating mechanism is arranged on the installing platform, the
tower tube, the
machine cabin, the power generator, the gearbox and the
impeller are positioned in the water, the upper end part of the
tower tube is fixedly arranged on the rotating mechanism, the power generator and the gearbox are arranged at one side of the
machine cabin, the
impeller consists of a wheel hub and a plurality of blades, a center shaft of the wheel hub is connected with the power generator through the gearbox, the telecentric ends, far away from the center of the wheel hub, of the blades are provided with a wheel ring in a sleeving way, the wheel ring is of a cylindrical structure with the hollow side wall, and through the hollow structure of the wheel ring, the
buoyancy obtained by the impeller in water counteracts the
self weight of the impeller, so the impeller becomes a zero-weight impeller, the installing platform is fixedly arranged on a suspension framework consisting of a floating tube, and the suspension framework is fixed and floats on the water surface through pull ropes and ground anchors. The
water flow power generating device has the advantages that the impeller can fast rotate under the
water flow impact without overcoming the
self weight, and the work obtained through the fast rotation is completely converted into the power generating power, so the power generating efficiency is greatly improved.