Short‐circuit‐constrained transmission expansion planning with bus splitting flexibility

Abstract

Incorporation of the short‐circuit level constraints in the transmission expansion planning (TEP) has a direct impact on the final solution. Conventionally, in TEP models, a substation is tackled as a single node where are all transmission lines, power transformers, and generating units are connected to each other. However, bus splitting is a common option in most substations that divides the connected elements into two groups. Doing so, bus splitting can alter the flow path impedances and accordingly manage the short‐circuit levels. Here, the short‐circuit level constraints are modelled in terms of conventional TEP and bus splitting decision variables. The modelling process is very complex and some non‐linear terms appear in the models. To have a tractable model in real‐world problems, the non‐linearities are converted to linear equivalents making the final TEP model conforming the mixed‐integer linear programming format. The performance of the proposed model is examined on the 24‐bus reliability test system. The results show that incorporation of the bus splitting option in the TEP problem decreases the total cost of the optimal expansion plan.