Polymorphic Virtual Synchronous Generator: An Advanced Controller for Smart Inverters
Author:
Moulichon Audrey123ORCID, Alamir Mazen2ORCID, Debusschere Vincent1ORCID, Garbuio Lauric1ORCID, Hadjsaid Nouredine1ORCID
Affiliation:
1. Univ. Grenoble Alpes, Grenoble INP, CNRS, G2ELab, 38000 Grenoble, France 2. Univ. Grenoble Alpes, Grenoble INP, CNRS, GIPSA-Lab, 38000 Grenoble, France 3. Power Conversion Department, Schneider Electric Industries, 38000 Grenoble, France
Abstract
Virtual synchronous generators (VSGs) are one of the most relevant solutions to integrate renewable energy in weak grids and microgrids. They indeed provide inverters characteristics of rotating machines (inertia for instance) that are useful for stabilizing the system, notably in the context of the high variability of the production. Thanks to the virtual characteristics of the VSG, the virtual parameters of the emulated synchronous machine can be optimally adapted online as a function of the electric environment of the inverter. We call that inverter’s control a polymorphic VSG. The online adaptation of the critical control parameters of the VSG helps reduce the risk of deterioration of the inverter’s constituents that might be induced by harsh events (frequent in weak grids) but, more importantly, improves the robustness of the system. In this paper, four implementations of a polymorphic VSG controller are compared on a simple microgrid study case to a complete VSG model. For the test, polymorphic VSGs have to minimize frequency and voltage oscillations while withstanding short circuits, which is typically a requirement for units in this context. One of the controls is based on recurrent optimization over a prediction time horizon, and two sub-optimal ones target practical implementation in industrial inverters with limited computational power. Results show a clear reduction in incidents in the microgrid thanks to the controllers. The error reduction with the complete polymorphic VSG is up to 100% for the voltage, 32% for the currents, and 79% for the duty ratio. Those values are decreased by 30 to 50% with the sub-optimal controllers but for a reduction in the computational burden of more than 97%. Recommendations are proposed for the development of an auto-adaptive polymorphic VSG from a high technology-readiness-level perspective, i.e., targeting a compromise between error reduction and computational burden.
Funder
Association Nationale Recherche Technologie
Subject
Energy (miscellaneous),Energy Engineering and Power Technology,Renewable Energy, Sustainability and the Environment,Electrical and Electronic Engineering,Control and Optimization,Engineering (miscellaneous),Building and Construction
Reference22 articles.
1. Steady-State Analysis of Maximum Photovoltaic Penetration Levels on Typical Distribution Feeders;Hoke;IEEE Trans. Sustain. Energy,2013 2. Driesen, J., and Visscher, K. (2008, January 20–24). Virtual synchronous generators. Proceedings of the IEEE Power and Energy Society General Meeting (PESGM), Pittsburgh, PA, USA. 3. A Virtual Synchronous Machine Implementation for Distributed Control of Power Converters in Smartgrids;Suul;Electr. Power Syst. Res.,2015 4. Virtual Synchronous Generators: A Survey and New Perspectives;Bevrani;Int. J. Electr. Power Energy Syst.,2014 5. Wang, Z., Yi, H., Wu, J., Zhuo, F., Wang, F., and Zeng, Z. (2017, January 26–30). Dynamic Performance Analysis of Paralleled Virtual Synchronous Generators under Grid-connected and Islanded Mode. Proceedings of the IEEE Applied Power Electronics Conference and Exposition (APEC), Tampa, FL, USA.
|
|