Double flexible direct current unit power transmission system and power transmission mode switching method thereof

Abstract

The invention discloses a double flexible direct current unit power transmission system and a power transmission mode switching method thereof. The switching method comprises the following steps: determining a power transmission mode of the double flexible direct current unit power transmission system, and determining a to-be-switched flexible direct current unit according to the power transmission mode, wherein the power transmission mode comprises a distribution mode and a combined transmission mode; isolating the flexible direct current unit to be switched from an alternating current system correspondingly connected with the flexible direct current unit, and switching the control mode of the flexible direct current unit to be switched from a power control mode to a voltage frequency control mode; and switching the flexible direct current unit to be switched to a connecting line corresponding to another alternating current system by adopting a synchronous switching-on function. Compared with the prior art, the technical scheme provided by the invention can realize on-line switching of the power transmission mode of the double-flexible direct-current unit power transmission system, avoids locking operation on the flexible direct-current units, and is beneficial to reducing the switching complexity, so that the operation efficiency of an operator can be improved, and the operation burden of the operator is reduced.

Description

technical field [0001] Embodiments of the present invention relate to the technical field of power transmission and distribution, and in particular, to a power transmission system with dual flexible DC units and a method for switching power transmission modes. Background technique [0002] With the rapid development of power grid technology, the safety and reliability of the power grid system has become the top priority. [0003] In a dual flexible DC transmission project, two flexible DC units are usually included to supply power to multiple AC systems at the rear end. When switching the transmission mode of the two flexible DC The DC unit is out of service, and the corresponding AC switch is re-operated to complete the switching of the power transmission mode. The whole process requires operations such as locking, charging, and unlocking of the DC unit, which increases the operating burden of the operator and the live shock of the equipment. Contents of the invention ...

AI Technical Summary

Problems solved by technology

[0003] In a dual flexible DC transmission project, two flexible DC units are usually included to supply power to multiple AC systems at the rear end. When switching the transmission mode of the two flexible DC The direct unit is out of service, and the corresponding AC switch is re-operated to complete the switching of the power transmission mode. The whole process requires locking, charging, unlocking and other operations on the flexible direct unit, which increases the operating burden of the operator and the live shock of the equipment.

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