Abstract: The introduction of P2G （power to gas） equipment into integrated energy systems has strengthened the coupling between electricity and natural gas networks, reduced the abandonment of wind power, but also reduced to a certain extent the optimization of renewable energy sources in energy hubs. Energy conversion occurs during dispatch, which reduces the energy efficiency and generates energy losses. In this context, a two-layer optimization scheduling model is proposed to reduce the repetitive conversion of energy sources. The KKT condition is used to convert the two-layer model into a single-layer model, and the scheduling operation schedule of the conversion equipment and the minimum operating cost of the system are optimized.Finally, four different typical scenarios are used to verify the system in the example. The results show that the proposed optimized scheduling model can reduce the operating cost of the system and improve the energy efficiency. The scheduling model that considers repeated energy conversions has significantly improved economics

Key words: integrated energy system, energy hub, optimal dispatch, repeated energy conversion, two-layer optimization