Impedance Modeling for Three-Phase Inverters with Double Synchronous Reference Frame Current Controller in the Presence of Imbalance

This article presents a small-signal model for power-electronics converters that use a typical control structure in wind energy applications: the double synchronous reference frame current control. The article considers the presence of unbalanced currents and voltages, and analyzes their impact on the frequency couplings of the converter. In...

On the Importance of Tracking the Negative-Sequence Phase-Angle in Three-Phase Inverters with Double Synchronous Reference Frame Current Control

A voltage imbalance at the AC terminals of a three-phase inverter creates a ripple in the power signal on the DC side. In order to minimize this ripple, several techniques can be applied, in which a double Synchronous Reference Frame (SRF) current control structure is very typical. In this approach, both the positive and negative sequence...

Output Impedance Modelling and Sensitivity Study of Grid-Feeding Inverters with Dual Current Control

In this paper, the output impedance of a three-phase inverter based on a dual current control (also called double synchronous reference frame current control) is modelled, which includes: the current loop gain, the control delay, and the Phase-<br/>Locked Loop (PLL). The impact of these parameters on the impedance is then analysed by a...

Type IV Wind Turbine System Impedance Modelling for Harmonic Analysis: On the Use of a Double Synchronous Reference Frame and Notch Filter

Several efforts are being done nowadays to improve the modelling of Wind Turbine Systems (WTSs) for harmonic analysis in Offshore Wind Power Plants (OWPPs). Due to the high influence of the different control structures in the Power Electronic Converters (PECs) on the dynamic response of a WTS, each structure needs to be modelled specifically....