Active Transmission Module for Generator Speed Regulation

In this paper, an active transmission motion control system is proposed that appropriately regulates the speed of a generator. In conventional approaches to power electronic control, an AC/DC frequency converter is essential for the generator to be directly connected to the grid because of the generator's irregular power output. In this paper, a mechanical motion control structure is proposed, where the generator speed is regulated through a planetary gear-based transmission module with an auxiliary driving motor. When the input power to the generator is less than required, the auxiliary motor supplies assistive power and actively increases the gear ratio. Conversely, when the input power is more than required, the excess power is consumed by the motor to actively decrease the gear ratio. The generator speed is therefore kept constant at the utility grid frequency. The advantage of the proposed approach is that the generator can directly output stable AC electricity without the use of additional electronic power converters. The feasibility of the proposed approach was verified by experiments and kinematic speed analyses.