Stability analysis and active stabilization by a centralized stabilizer of Voltage-Source-Rectifier Loads in AC microgrids

Abstract

This paper deals with the stability analysis and the active stabilization of Voltage-Source-Rectifier Loads in AC microgrids using a centralized stabilizer. A model of this system is first performed considering the voltage loop dynamics of the rectifier and stability analysis is done using the indirect method of Lyapunov. The stabilizability study realized with Lie algebra shows that the action of an external stabilizer is limited to the AC side of the system. This stabilizer is an inverter only dedicated to the stabilization of the AC bus of the system at the connecting point. To improve the stability area, a feedback control of the stabilizer based on the small-signal theory is developed. A theoretical analysis, simulations and experimental results are presented to evaluate the effectiveness of the proposed method.

A Series-<italic>LC</italic>-Filtered Active Damper With Grid Disturbance Rejection for AC Power-Electronics-Based Power Systems

“…Passive dampers are, in general, robust, but they incur additional power losses [10], [11]. Lower-loss active dampers are therefore preferred, which however require the use of the high-bandwidth converters for suppressing those high-frequency resonances burdening the power systems [12]- [14].…”

“…Manuscript Although lossless damping of resonances can be achieved by these control additions, their effectiveness is usually influenced by the variations of the system conditions [7]. Alternatively, additional passive or active devices can be used as dampers for stabilizing the systems [10]- [14]. Passive dampers are, in general, robust, but they incur additional power losses [10], [11].…”

A series-LC-filtered active damper for ac power electronics based power systems

“…There are, in general, two major approaches for stabilizing power electronics based power systems [9]- [16]. The one is to re-shape the dynamic properties of the converters by adding control loops or digital filters into the control system [9]- [11].…”

“…Lossless damping can thus be attained, yet their effectiveness is usually affected by the dynamics of other converters and the system conditions [9]. The other type is to employ additional devices, either passive or active, as dampers for stabilizing the systems [12]- [16]. Passive dampers generally achieve a robust damping, but additional losses are inevitable [12], [13].…”

“…Passive dampers generally achieve a robust damping, but additional losses are inevitable [12], [13]. Active dampers with the reduced losses are thus preferred [14]- [16], which are based on a converter with a high control bandwidth, for selectively damping those high-frequency resonances in the power systems [14]- [16].…”