考虑安全运行边界的低压配电交直流组网控制策略及工程应用OA

With the explosive growth of distributed power sources and the widespread integration of new DC loads,the imbalance of load rate in low-voltage power distribution area is prominent,which brings severe challenges to the safety and stability of distribution network.The paper proposes a load rate balancing control strategy applied to low-voltage interconnection substations,which fully considers the safe operation boundary and achieves cluster operation and load balancing regulation of multiple substations.Firstly,the flexible interconnection of AC/DC network architecture and typical operating modes are presented;Secondly,a power coordination control strategy is designed so as to achieve the balanced and independent distribution of the unbalanced power in the entire network;Further,taking into account the sudden increase in single unit high load power and conventional load superposition,this paper configures a VSC safe operation boundary to address the short-term heavy overload and even overcurrent tripping of distribution transformers caused by the increase in AC load.To achieve maximum load balancing of distribution transformer clusters under extreme unbalanced conditions,this study proposes an over limit power cycle sharing algorithm.Finally,the simulation verification and engineering practice results show that the control strategy presented in this paper could effectively solve the power imbalance problem in power distribution area and ensure the safety and stability of the system when the loads fluctuate significantly,which has great practical significance and promotion value.