High-voltage direct-current power transmission multi-channel supplementary damping control method based on variable structure

Abstract

The invention discloses a high-voltage direct-current power transmission multi-channel supplementary damping control method based on a variable structure. The high-voltage direct-current power transmission multi-channel supplementary damping control method has the characteristics that sub-synchronous and low frequency oscillation frequencies and damps, and a system reduced-order model are identified by a TLS-ESPRIT (Total Least Squares-Estimation of Signal Parameters via Rotational Invariance Techniques) algorithm with high operation efficiency and anti-interference capability; a variable structure control principle is combined and an attached controller containing a virtual state variable is designed; finally, a state observer is led in to eliminate the virtual state variable so as to realize an HVDC (High Voltage Direct Current) variable structure controller with an output feedback form; then a variable structure control theory is used for designing a multi-channel direct-current attached damping controller so as to reduce the mutual influences between oscillation modes; the sub-synchronous and low frequency oscillation can be inhibited synchronously. The method is efficient and feasible; the variable structure control theory has strong disturbance rejection on complicated changeable working conditions of an actual power grid; meanwhile, a multi-channel structure is utilized by using the controller to solve a coordinated control problem among the plurality of controllers; the invention provides a controller design method of an actual large power grid with very strong operability.

Description

Technical field [0001] The invention relates to a variable structure-based high-voltage direct current transmission multi-channel additional damping control method, which belongs to the field of high-voltage direct current transmission. Background technique [0002] At present, my country has formed two AC / DC hybrid power grids from the State Grid and China Southern Power Grid. While grid interconnection brings significant economic and social benefits, its large scale and complex operating characteristics also pose new challenges to the power operation sector. . The problem of weakly damped low frequency oscillation is one of the typical challenges faced by large-scale grid interconnection. High Voltage Direct Current (HVDC) power transmission technology has become an important technical solution in the interconnection of large-scale power grids due to its economy and its own unique fast response characteristics embodied in long-distance and large-capacity transmission. With the...

AI Technical Summary

Problems solved by technology

A multi-channel DC additional damping controller device that simultaneously suppresses subsynchronous oscillations and low-frequency oscillations has been studied (Zhao Rui, Li Xingyuan, Liu Tianqi, etc. Design of a multi-channel DC additional damping controller that suppresses subsynchronous and low-frequency oscillations[J], Electric Power Automation Equipment, 34(3):89-92), however, the robustness of the above-mentioned controller and the adaptability to the complex variability of the actual power grid are still not resolved

Images