Low-voltage four-port flexible direct current system structure and control method

Abstract

The invention relates to a low-voltage four-port flexible direct-current system structure and a control method, and the structure comprises a pair of ring net racks which employ a petal-type wiring mode. The pair of ring net racks are connected through a four-port flexible direct-current system, the ends 1, 2, 3 and 4 of the alternating-current side of the four-port flexible direct-current system are respectively connected with the I-section bus of the first power distribution station, the I-section bus of the second power distribution station, the II-section bus of the second power distribution station and the II-section bus of the first power distribution station, and the direct-current sides of the four ports are interconnected back to back so as to realize a petal-type wiring inter-petal closed-loop operation mode of the first and second substations. When a fault occurs, rapid load transfer can be realized by switching operation modes, and the power supply reliability is improved.

Description

technical field [0001] The invention belongs to the technical field of hybrid AC and DC distribution networks, in particular to a low-voltage four-port flexible DC system structure and control method. Background technique [0002] The distribution network is connected to the main grid frame and connected to thousands of households. It is not only a key technology to connect the main grid, various users and distributed energy, but also an important part of building a strong smart grid. The operation control of the 10kV distribution network is relatively simple. Although the 10kV distribution network adopts the ring network connection mode, most of them are single-radiation open-loop operation. With the development of economy and society and the gradual advancement of smart grid, the disadvantages of open-loop operation are gradually becoming prominent. Open-loop operation not only affects the further improvement of power supply reliability, but also cannot meet the friendly ...

AI Technical Summary

Problems solved by technology

Open-loop operation not only affects the further improvement of power supply reliability, but also cannot meet the friendly access of large-scale distributed energy

[0003] Economically developed countries (regions) have adopted the ring-network-closing grid system based on distribution automation terminals to realize the closed-loop operation of the distribution network. However, when a fault occurs, although the power supply can be transferred through the tie line, there is still a second level. The occurrence of power failure, cannot meet the needs of high-sensitivity loads such as precision processing and semiconductor manufacturing enterprises

And with the development of distributed energy, this system cannot meet the friendly access of large-scale distributed energy

[0004] After searching, no documents of the prior art identical or similar to the present invention were found

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