Modeling, Analysis, and Stabilization of Converter-Fed AC Microgrids With High Penetration of Converter-Interfaced Loads

Abstract

This paper addresses ac microgrid stability under high penetration of converter-interfaced loads (CILs). According to the Nyquist admittance ratio criterion, destabilizing interaction dynamics are yielded among the interfacing voltage-source inverter (VSI) of the ac microgrid and CILs. Active stabilization techniques are proposed to maintain the overall system stability from the VSI side using admittance-based small signal analysis. Sensitivity and robustness analyses are presented to assess the dynamic coupling among active damping and voltage tracking controllers of the interfacing VSI. A complete Matlab/Simulink model of an ac microgrid with multiple CILs is used to demonstrate the effectiveness of the proposed active compensation techniques.

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

“…The system state equations (9) have been linearized around an operating point. Using parameters given in TABLE 2, bode diagram of (Fig.…”

“…The DC bus has been identified as the unstabilizable subsystem. If the DC dynamics (Yd el and Jlvl ) are removed from the state-space equation (9) and if the DC voltage loop is considered ideal such that PL lref (X) = PL l , the system becomes stabilizable. The new state-space is given in (20).…”

“…In AC power systems, the impedance compatibility, based on the generalized Nyquist criterion, is a method which can guarantee the possibility of interconnecting two or more converters [7] - [9]. Two converters can be put in cascade if the ratio source impedance/ load impedance does not encircle the point -1.…”

A Data-Driven Modeling Strategy for Smart Grid Power Quality Coupling Assessment Based on Time Series Pattern Matching

“…In recent years, the increased penetration of distributed generations and power electronic loads has aggravated power quality (PQ) pollution in power systems [1,2]. Moreover, the extensive use of adjustable speed drive systems, computer systems, and precision production lines has brought forward higher requirements for PQ [3][4][5].…”

Resonance analysis in parallel voltage-controlled Distributed Generation inverters

“…Consequently, the islanded networks that are dominated by multiple DG inverters are becoming important components of the smart distribution grids [4]. The increasing concerns over the control and stability of such inverter-based islanded systems have been raised [5].…”