Method for enhancing AC-DC hybrid power grid DC power enhancement capacity

Abstract

The invention discloses a method for enhancing AC-DC hybrid power grid DC power enhancement capacity. Whether the DC power is the rated value is judged, the control mode of a DC system is determined,and the reduced Jacobian matrix of an AC-DC hybrid power grid is solved; if the DC power is less than the rated value, fitting of the relationship between the converter station AC bus voltage and theconverter transformer ratio is performed, the minimum converter station AC bus voltage enabling the DC power to reaching the rated value is solved according to the quasi-steady-state model of the DC system increment form and the reduced Jacobian matrix of the AC-DC hybrid power grid, and the operation point of the synchronous phase modifier of the DC line rectification side and the inversion sideis adjusted to perform phase operation to absorb reactive power if the DC power is the rated value and the DC power enhancement amount does not reach the preset value; and the estimation value of theexcitation voltage reference value adjusting amount of the synchronous phase modifier of the inversion side is solved according to the relationship between the excitation voltage reference value of the synchronous phase modifier of the inversion side and the DC power enhancement amount, and the excitation voltage reference value adjusting amount of the synchronous phase modifier of the rectification side is determined through simulation.

Description

technical field [0001] The invention belongs to the field of power system operation and control, and in particular relates to a method for improving the DC power boosting capability of an AC-DC hybrid grid. Background technique [0002] As an important part of the main grid of the AC-DC hybrid power grid, the DC line plays an important role in the power modulation capability of the power grid. Through the cooperation between the sending and receiving ends of the DC line, the coordinated control of the AC-DC system is realized. Resist the impact of disturbances on the system. For example, when the large-capacity units at the receiving end cause a shortage of active power due to failure and outage, the DC power boost can be used to reasonably distribute the active power deficit at the receiving end between the sending and receiving ends. , improve the ability of the power grid to withstand the impact of faults. [0003] With the successive construction and operation of DC tra...

AI Technical Summary

Problems solved by technology

[0003] With the successive construction and operation of DC transmission projects, DC power boost plays an increasingly significant role in the safety and stability control of AC-DC hybrid power grids. However, during the process of DC power boosting, the converter station absorbs a large amount of reactive power from the system. As a result, the AC bus voltage of the converter station is significantly reduced, and the DC power boost cannot reach the set value

In order to improve the DC power boosting capability, the existing technology usually adjusts the excitation voltage reference value of the synchronous generator on the rectification side and inverter side of the DC line based on experience to control the AC bus voltage of the converter station, but this adjustment cannot guarantee to achieve the expected DC power boost effect, improper adjustment will even reduce the DC power boost

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