Seamless Integration of an Autonomous Induction Generator System into an Inverter-Based Microgrid

Abstract

A control strategy for an autonomous induction generator (IG) system synchronization and seamless transfer to an inverter-based microgrid (MG) is presented in the current paper. The IG system control in autonomous mode is performed by a combination between a Voltage Source Inverter (VSI) and a Dump Load (DL). The MG consists of an MG leading inverter having on its DC side a supercapacitor-based energy storage system, two MG supporting inverters, and local loads. The paper presents the IG control part for the VSI-DL system, as well as the synchronisation algorithm that enables the smooth interconnection with the MG. An analysis of the IG impact on an islanded MG is also provided. Experimental validations accomplished on a complex laboratory test-bench have focused on the dynamic events associated with the IG system connection/disconnection to/from the MG and also on the MG response to a load being turned on and off when the IG operates connected to the MG. The obtained results have shown that the proposed synchronization algorithm ensures a seamless transfer for the IG system from autonomous to MG connected mode and vice-versa. Moreover, when a significant load transient occurs within the MG operation, the IG presence does not alter the MG stability.

Advanced Distributed Wind Turbine Controls Series: Part 4-Wind Energy in Microgrids – Microgrids, Infrastructure Resilience, and Advanced Controls Launchpad (MIRACL)

“…reference microgrid frequency, responds in a matter of milliseconds to the frequency dip upon disconnection at 10 s. This rapid response is in line with the simulation and experimental validation results for an induction generator from Ion and Serban (2019).…”