Optimal configuration of coupling equipment for electric-gas integrated energy system considering the influence of voltage sag

As the most serious and frequent power quality problem, voltage sag significantly impacts the electricity-gas integrated energy system (EG-IES) through sensitive coupling equipment. In order to reduce the economic loss of the EG-IES system caused by voltage sags, this paper proposes an optimal configuration method for the EG-IES coupling equipment. The paper first analyzes voltage sag impacts in the normal operation of EG-IES through coupling equipment. Then, tolerance characteristic curves of the compressor and gas turbine are presented, and an economic loss model caused by voltage sag is established. Finally, an optimal configuration model is established considering the cost of coupled equipment and voltage sag loss. The method is applied to the EG-IES composed of IEEE14 nodes and gas network 11 nodes, proving that the method can effectively reduce the loss of EG-IES caused by voltage sags while considering the equipment installation cost.