Series self-excited HVDC generation

A new concept in HVDC generation simplifies the design of unit-connected generator-convertor plant. The generator exciter winding is connected in series with the output of the HVDC convertor and takes the place of the conventional smoothing reactor. As the existing steady-state AC-DC formulation is not directly applicable to the series connection a new algorithm is developed to simulate its performance. The results of the simulation show that series excitation is less efficient at low power levels but extends the temporary power conversion capability of the unit connection and permits fast fault clearances