PURPOSE: To operate a power generator unit by circulating electricity generated by a generator without receiving energy from the outside except for an initial stage.

CONSTITUTION: Hydraulic struts 3 are expanded and contracted and rotary swash disks 2, 2a are provided slantwise. Accordingly, a rotary blade receiving wheel 4 disposed in a rotary blade 1 is moved downward on a downward slope. Expansion and contraction of the hydraulic struts 3 in sequence are converted into a rotating motion. The rotating motion is transmitted from a gear 8 fitted to a spindle 5 to a gear 8a fixed to a generator 7, thereby rotating the generator 7. A circulating generator unit for supplying electricity generated by the generator 7 to a hydraulic distributor 6 so as to vertically expand and contract the hydraulic struts 3 is of a regeneration type since electric generated power becomes larger than consumed electric power.