The invention relates to a wind power generation system, in particular to wind power generation equipment which adopts a dumbbell air-collecting wind tunnel to carry out shrinkage pressurization on natural wind by caliber change, has the functions of increasing wind speed, controlling air current and strengthening wind pressure, and acquires large-scale wind power by adopting an energy-collecting impeller. The wind power generation system selects an appropriate wind power field, constructs the dumbbell wind tunnel in a windward direction to transit to an energy-collecting section through a stabilization section and a shrinkage section, and then sets a wake flow section and an exit section at a rear end; and a tunable wind wheel is arranged in the energy-collecting section to drive a generating unit and obtain electric energy. The wind power generation system of the invention is provided with a speed measuring and adjusting device, a safety device, a decompression device and a freezing, snow and lightning protection device.