The Quietrevolution-Gorlov helical turbine (GHT) is a water turbine evolved from the Darrieus turbine design by altering it to have helical blades/foils. The physical principles of the GHT work are the same as for its main prototype, the Darrieus turbine, and for the family of similar vertical axis wind turbines which includes also Turby wind turbine, aerotecture turbine, Quietrevolution wind turbine, etc. GHT, Turby and Quietrevolution solved pulsatory torque issues by using the helical twist of the blades.
The resulting work, all mechanically printed completely on a 3D printer. A DC motor with a permanent magnet serves as a generator. The motor voltage at the output is 1.8V / 1 RPS.
Wiki: https://en.wikipedia.org/wiki/Quietrevolution_wind_turbine