Single-circuit DC large-signal modulation controller and its control method based on ping-pong control

Abstract

The invention is a single-circuit DC large-signal modulation controller based on ping-pong control and a control method thereof. The single-loop DC large-signal modulation controller based on ping-pong control includes a sampling controller (S1), a differential controller (S2), a power controller (S3), a power limiter (S4) and a power converter (S5). The present invention can realize real-time on-line monitoring of the running state of the AC-DC transmission system. When serious AC faults or other faults such as single-circuit DC bipolar blocking occur, the DC controller can quickly judge the stability of the system and formulate a large DC signal according to the degree of stability. The modulation strategy, real-time and fast emergency modulation of DC power, effectively controls the power balance relationship between regions during the swinging process of the generator group, and plays a role in suppressing the swing of the power angle and improving the stability limit.

Description

technical field [0001] The invention relates to the field of transient stability control of AC and DC transmission systems, in particular to a single-circuit DC large-signal modulation controller based on ping-pong control and a control method thereof. Background technique [0002] As more and more high-power direct current transmissions are concentrated in the load center, the huge scale and rapid control response capability of direct current transmission have brought a series of complex and profound impacts on the dynamic characteristics, stability risks and control methods of the power grid. Variety. Among them, the fast active power adjustment capability of DC provides a new and effective means for improving the synchronization and stability of large power grids. [0003] The transient instability of large AC and DC power grids under severe AC faults or DC bipolar blocking faults is still the main constraint that limits the power transmission capacity of the grid. At p...

AI Technical Summary

Problems solved by technology

At present, the AC power grid has always lacked a real and effective means of suppressing the problem of inter-regional active power imbalance and synchronous generator power angle swing caused by short circuit.

Both PSS and FACTs of generators are limited by their active power flow regulation capabilities, and can only provide damping for small power oscillations, but it is difficult for large-scale power grids to stabilize transiently, especially in the first to third swing periods. good inhibitory effect

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