Introduction: This paper presents an approach for multistage expansion planning of the active distribution system network problems by considering multiple strategies based on system investment cost, including renewable energy sources based on distributed generation units, operational cost, and reliability.
Objective: The developed framework model fulfills the prospects related to techno-economical and reliable multistage expansion planning of active distribution system network for the sustainable development of electric power system.
Methods: The mathematical model of the multi-objective function has been developed with the investment decision variables to compute the investment cost. The reliability of the active distribution system network is evaluated in non-supplied energy costs under contingency conditions with and without DGs.
Results: The result validates the constraints associated with planning, investment decisions, power quality, and reliability of the system.
Conclusion: This study also demonstrates the improvement in per unit (p.u.) voltage of bus nodes for each period of network expansion with DGs over the planning horizon. The proposed method is tested and validated on a 54-bus, 11 kV long-term active distribution network.
Keywords: Multistage expansion planning, active distribution system network, distributed generation, renewable energy sources, non-supplied energy cost, DG, electric power.