Stability control for LC-L filter based load side converter of BDFG ship shaft power generation system without extra damping

In the stand-alone brushless doubly fed generator (BDFG)-based shaft power generation system, the stator power winding leakage inductance leads to the strong coupling between load side converter (LSC) and BDFG. In this study, the leakage inductance was used as a part of LCL filter. The difference between LC-L and conventional LCL filter has been analyzed to reveal the damping characteristic that LC-L has in absence of extra damping method. Taking the effect of digital control into account, the relationship between the damping characteristic of LC-L and LC filter parameters has been deduced. The stability and robustness of the system in both situations have been studied Theoretical analysis is validated by simulation and experiment.