A Seamless Transfer Control Strategy of SNOP for the Critical Load Safety Under Network Faults

The development of intelligent distribution network gradually evokes the reform of distribution network power supply mode. Soft normally open point (SNOP) is a new type of controllable power electronic device which is likely to take place of traditional switches, namely normally open switch (NOP), in distribution network. With the application of SNOP in distribution network, the flexibility and controllability of the network can be greatly improved. Considering network faults, normal power supply to critical loads can be guaranteed by transferring the working mode of SNOP. Thus, a novel seamless transfer control strategy of SNOP, which takes pre-synchronization into account, is proposed in this paper. The effectiveness of the proposed control strategy is demonstrated through simulation and experimental results.