Series-connection multiport direct current power flow controller based on MMC

Abstract

The invention relates to a series-connection multiport direct current power flow controller based on an MMC and belongs to the technical field of electric power. According to the series-connection multiport direct current power flow controller based on the MMC, from the aspect of power flow control, the multiport direct current power flow controller of a series-connection structure is popularizedfrom a power flow controller in a simple direct current power grid, and the problem that the direct current power grid power flow cannot be controlled is effectively solved. The series-connection multiport direct current power flow controller refers to the steps that multi-direct-current-voltage-class structures most suitable for being interconnected simultaneously are selected; an internal modelof a topological structure is built; a multi-voltage-class direct-current power grid model containing SM-DCPFC is built; and the situation that the multiport power flow controller can flexibly controlthe line power flow under various situations is verified through simulation. The alternating current side of the multiport power flow controller is connected with nearby alternating-current power supplies such as a convertor station, a power substation and an offshore wind plant through a transformer, the public alternating current side is connected with the alternating-current power supplies, and the alternating-current bus voltage is more stable.

Description

technical field [0001] The invention belongs to the technical field of electric power. Background technique [0002] The traditional AC transmission structure and operation technology are facing huge challenges in accessing new energy, which has once again attracted people's attention to DC transmission, which can well solve the problem of new energy grid integration. In recent years, scholars at home and abroad have studied HVDC transmission from simple to complex, from the most basic commutation HVDC transmission at both ends of the grid to the current multi-terminal voltage source HVDC transmission, from point-to-point topology to a network with a large number of DC lines. Ring and grid structure, the redundancy of the system has been greatly improved, but the power flow of the line is far from meeting the actual requirements. The unreasonable distribution of the power flow will cause the overload of the line, resulting in low-efficiency operation of the DC power grid and...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to start from the perspective of power flow control, from the power flow controller in the simple DC power grid, to promote the DC power flow controller with multi-port series structure, and effectively solve the problem of uncontrollable power flow in the DC power grid based on MMC. Port DC Power Flow Controller

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