Middle-voltage three-port flexible multi-state switch topology based on power electronic transformer

Abstract

The invention discloses a middle-voltage three-port flexible multi-state switch topology based on a power electronic transformer. The topology of the flexible multi-state switch is composed of three serial output stages and a high-frequency isolating stage. Each serial output stage comprises three phases. Each phase comprises N serial AC-DC current transformer, and totally three AC-DC transformers exist. The high-frequency isolating stage comprises 3N three-port high-frequency transformers and 9N AC-DC current transformers, wherein each three-port high-frequency transformer and three AC-DC current transformers form a high-frequency isolating stage unit. The high-frequency isolating stage unit comprises 3N high-frequency isolating stage units totally. Each high-frequency isolating stage unit is connected with three AC-DC current transformers which are affiliated to three serial output stages. The topology can realize interconnection and power flow control of three middle-voltage power distribution lines and can replace and surpass the function of a traditional mechanical contact switch. A simulation result verifies effectiveness of the topology and a high reference value is realized for engineering application.

Description

technical field [0001] The invention belongs to the field of flexible multi-state switches, and relates to a modular, medium-voltage, three-port flexible multi-state switch topology. Background technique [0002] In the future smart distribution network, the widespread access to distributed power sources will aggravate the uncertainty of system operation and bring about a series of problems, such as voltage crossing and line overloading. These problems prompt the real-time network reconfiguration and active power management of the distribution network. At present, the network reconfiguration of the distribution network mainly relies on traditional mechanical contact switches. Due to the limitations of switching loss and inrush current, traditional mechanical switches cannot be frequently disconnected, which limits the real-time performance of distribution network reconfiguration, making it difficult to Meet the needs of the future smart distribution network. [0003] The f...

AI Technical Summary

Problems solved by technology

Under different voltage levels, power levels, and port numbers, the specific topology that flexible multi-state switches can adopt and the pros and cons of different topologies are still a research blank.

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