With the rapid development of high proportion of new energy connections and new types of loads

distribution networks are facing new challenges in terms of operational economy

low-carbon performance and protection reliability. This paper first proposes a day-ahead low-carbon economic optimization scheduling strategy for distribution transformer areas that takes into account flexible load aggregation and regulation. By evaluating the demand for regulation and the potential of flexible resources

a cost-benefit optimization model is established to achieve dual goals of economy and low-carbon. Secondly

for micro-grid systems with multiple photovoltaic connections

the fault current characteristics and relay protection mechanisms are analyzed

and a positive and negative sequence network model is established. Through simulation

the impact of different photovoltaic connection methods on protection performance is verified. Finally

case simulations show that the proposed scheduling strategy can effectively reduce operating costs and carbon emissions

and the proposed protection methods can improve system reliability.