Analysis on damping characteristics of hybrid multi-infeed DC system with wind farm

Abstract EN

The interaction between AC and DC systems in hybrid multi-infeed direct current (HMIDC) system has a significant effect on the damping characteristics of the system, meanwhile, the doubly-fed induction generator (DFIG)-based wind turbine (WT) makes the system’s structure more complicated.

It is challenging to analyze the system’s stability quantitatively.

In this article, wind power joined the HMIDC system.

Then, based on the basic principle of wind generation and low frequency oscillation (LFO) the influence of the WT’s access points and the capacity of the WT on the damping characteristics and stability of the system is studied.

Based on the total least squares-estimation of signal parameters via rotational invariance techniques (TLS-ESPRIT) algorithm, and the system eigenvalue, frequency, damping ratio, and other information are obtained.

The analysis shows that when the WT is incorporated into different HMIDC system positions, the system has different oscillation modes and damping ratios.

And in these oscillation modes, the damping ratio gradually decreases with increasing oscillation frequency.

When the capacity of the WT is increased, the change of damping ratio is not apparent than before.

The eigenvalue analysis is well verified by simulation analysis on the PSCAD/EMTDC platform.