In existing literature, the emphasis is on the fault characteristics [15] and the operation planning of hybrid AC/DC power systems
However, few publications have addressed the issue of reducing short circuit currents by converting AC lines to HVDC.
For a power system, converting AC lines to HVDC can improve the network structure, thereby reducing short circuit currents.
Moreover, with the help of HVDC, the transmission capacity is increased and power transmission corridors are saved.
To this end, a new concept termed optimal transmission conversion (OTC) is proposed in this paper.
In our proposed OTC model, AC lines are strategically converted to HVDC for limiting short circuit currents when conducting transmission expansion planning.
The objective is to minimize the converting cost of HVDC and the constraints incorporate the short circuit currents limitation.
Moreover, since the transmission capacity of HVDC is large, the electrical energy transmission of the power system is improved as well