反向过载下计及变压器健康运行的配电网协同管理策略OA

With the introduction of carbon neutrality goals,the integration of large-scale renewable energy sources,such as solar and wind power,into the distribution network has led to an imbalance between the"generation-load"in the distribution network.On one hand,when the output power of renewable energy exceeds the load,reverse power flow between the transmission and distribution networks occurs,causing voltage security issues in the distribution network.On the other hand,when the output power from renewable energy significantly exceeds the load,transformers experience overloading or excessive loading,which diminishes the reliability of equipment operation.Since the capacity of transformers is difficult to change after installation,this paper proposes a collaborative management strategy to ensure the healthy operation of transformers in the new power system under reverse power flow overload conditions.First,a transformer usable life surface model is established based on the thermal life loss calculation model derived from the load guide.This model is then transformed and simplified using a feasible domain convexification method.Second,considering the bidirectional power flow characteristics of transformers,a comprehensive active and reactive power regulation model for the distribution network is developed.Finally,to minimize the operation cost of the distribution network,the collaborative management results for different ambient temperatures and expected transformer relative aging rates are obtained.Under the condition of ensuring voltage safety in the distribution network,overload management of transformers is performed.Case results demonstrate that maintaining transformer maximum reverse load coefficients no lower than 1.213,1.11,and 1.01 under 140%penetration scenarios at 20℃,25℃,and 30℃ respectively balances lifespan and economy.