This is a wind turbine for wind power generation which is constructed in many places in the world as the next-generation clean energy. Large size ECHT-FLEX Couplings have been used to connect the speed-up gears and power generators. The advantages are that the coupling provides allowance for misalignment because operation is affected by lifting/vibration caused by strong winds, no lubricating maintenance is required, and no backlash occurs. There is another advantage in that expanding the flange outer diameter of the hub allows a disc brake used as a holding brake to be integrated with the coupling.