Tidal current generating unit

A tidal current generating unit, comprising:

• a turbine, a hub, a generator, a bearing set and a fixed flange;
• wherein the generator comprises a stator and a rotor;
• the turbine is connected to the rotor of the generator by the hub;
• the rotor is rotatably mounted on an outer circumference of the stator of the generator via the bearing set;
• the stator of the generator is fixedly connected to the fixed flange;
• a rotating component comprises the hub and the rotor;
• and the turbine drives the rotating component to rotate to generate electricity;
• the turbine comprises a blade, and a density of the blade is much smaller than a density of seawater, such that the blade has sufficient buoyancy that offsets gravity of the rotating component in the seawater, and a load of the bearing set is reduced;
• the turbine further comprises a blade stem, a blade stem bearing, a pitch limiter, a forward pitch regulator and a reverse pitch regulator;
• a root of the blade is fixedly connected to the blade stem;
• a blade stem hole is radially distributed on the hub, and the blade stem is rotatably mounted in the blade stem hole by the blade stem bearing and is rotatable around a flange central axis of the blade in the blade stem hole;
• the pitch limiter comprises a first limiting edge and a second limiting edge connecting with the first limiting edge, the first limiting edge and the second limiting edge are protruding, and surround a rear end of the blade stem;
• the forward pitch regulator is arranged at one side of the pitch limiter, and the reverse pitch regulator is oppositely arranged at another side of the pitch limiter;
• a rear end of the blade stem is coaxially connected to the pitch limiter;
• when the blade is pushed by forward tidal currents, the blade, blade stem and pitch limiter are clockwise rotated around the flange central axis of the blade;
• when the blade is pushed by reverse tidal currents, the blade, blade stem and pitch limiter are counterclockwise rotated around the flange central axis of the blade.