This study proposes an innovative transmission mechanism, called parallel-type independently controllable transmission (ICT). The proposed mechanism can provide functions similar to those of infinitely variable transmission (IVT) or continuously variable transmission (CVT) mechanisms. The parallel-type ICT can transmit rotational output speed that can be independently regulated using a controller and is unaffected by the speed variation of the input shaft. Thus, a variable speed wind turbine can generate electricity with a constant frequency and improved quality. The kinematic characteristics, torque distribution, and power flow of this transmission mechanism were verified using a prototype of the ICT to demonstrate the feasibility of its application.