Method and device for optimizing AC channel power transmission capacity in AC-DC hybrid power grid

Abstract

The invention provides an alternating current channel transmission capacity optimization method and device in an alternating current / direct current hybrid power system. The method comprises the stepsthat double-machine equivalence is carried out on a transmission-side alternating current system according to the dynamic response curve of an alternating current / direct current hybrid power grid, soas to acquire a leading generator group and a hysteresis generator group; Thevenin equivalence is carried out on the alternating current / direct current hybrid power grid from the direct current side according to the leading generator group and the hysteresis generator group; and finally the operation mode of the alternating current / direct current hybrid power grid is adjusted according to the Thevenin equivalence result of the alternating current / direct current hybrid power grid; and the alternating current channel transmission capacity is optimized in the direct current hybrid power grid. According to the invention, the problem that an alternating current channel is impacted by the collapse of the transmission power of a direct current transmission system during a recovery process and thevoltage drop of a direct current conversion bus after the generator group oscillating aroused by certain faults in the transmission-side alternating current system is solved; and reference is provided for a power grid operator to arrange the operation mode of the alternating current / direct current hybrid power grid reasonably to ensure safe and stable operation of the alternating current / direct current hybrid power grid.

Description

technical field [0001] The invention relates to the technical field of power systems, in particular to a method and device for optimizing the transmission capacity of an AC channel in an AC-DC hybrid power grid. Background technique [0002] At present, my country's AC-DC hybrid grid has begun to take shape. Due to the interaction between the DC transmission system and the AC system, the AC-DC hybrid grid has become complicated. The safety and stability characteristics of the AC-DC hybrid grid are undergoing profound changes. The coupling characteristics between the DC transmission system and the AC system have not yet been clearly understood, especially as the characteristics of the dense transmission of the multi-circuit DC transmission system and the feed-in of the multi-circuit DC transmission system to the AC system at the receiving end have become increasingly prominent, the large-capacity DC transmission system The dynamic characteristics of the AC-DC hybrid grid have a...

AI Technical Summary

Problems solved by technology

[0005] 2) Limiting DC transmission power: Due to the large transmission power of the current DC transmission system, the fluctuation of the transmission power of the DC transmission system will have a great impact on the weak AC channel

[0006] Faults such as commutation failure in the DC transmission system may lead to severe oscillations between generator groups, which in turn will cause a decrease in the commutation bus voltage in the AC system at the sending end, affect the recovery characteristics of the transmission power of the DC transmission system, and cause another impact on the weak AC channel, resulting in The safety and stability margin of the AC-DC hybrid power grid is small, which seriously limits the transmission capacity of the AC channel

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