This paper proposes a control scheme to force homogeneity for heterogenous network of the grid-forming (GFM) inverters in power electronics dominated grid (PEDG) to enable their aggregation and coherent dynamic interaction. Increased penetration of the renewable energy in distributed generation (DG) fashion is moving traditional power system to a highly disperse and complex heterogenous system i.e., PEDG with fleet of grid-forming and grid-following inverters. Optimal coordination, stability assessment, and situational awareness of PEDG is challenging due to numerous heterogenous inverters operating at the grid-edge that is outside the traditional utility centric power generation boundaries. Aggregation of these inverters will not be insightful due to their heterogenous characteristics. The proposed control scheme to force enclaved homogeneity (FEH) enables an insightful aggregation of GFM that can fully mimic the given physical system dynamics. The proposed FEH scheme enables coherent and homogenized dynamic interaction of GFM inverters that enhances the PEDG resiliency. Moreover, different cluster of GFM can be merged into single cluster with minimal synchronization time and frequency fluctuations. Accurate reference models can be achieved that enables effective dynamic assessment and optimal coordination which results in resilient PEDG. Several case studies provided to validate the effectiveness of proposed FEH in network of GFM. Then, GFMs aggregation and developed reference model for the PEDG system is validated via multiple comparative case studies.
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A Corrective Scheme to Prevent Adverse Dynamic Interaction of Grid-forming Inverters
This paper proposes a control scheme that prevents the adverse dynamic interactions between the heterogeneously controlled grid-forming inverters (GFMI) in power electronics dominated grid (PEDG) towards a resilient self-driving grid. The primary controller of GFMIs in a grid cluster can vary based on their manufacturers such as virtual synchronous generation, droop control, power synchronization control, etc. Therefore, this can introduce heterogeneity among the network of GFMIs in PEDG. Resultantly, during the interconnection of GFMIs that are based on heterogenous primary controller poses various synchronization and dynamic interaction challenges in PEDG. For instance, severe fluctuations in frequency and voltage, high ROCOF, unintended reactive power circulation that poses a threat on the overall transient stability of the PEDG. Therefore, to mitigate these adverse dynamic interactions among the heterogeneously controlled GFMIs, a force enclaved homogenization (FEH) control is proposed in a supervisory level controller. This will autonomously adjust inertia coefficients of the each GFMI to have homogenous transient response and will enforce coherency among the heterogenous DGs. This will prevent the PEDG from the adverse dynamic interactions during an interconnection and load disturbance. Various case studies are presented that validates the effectiveness of the proposed FEH control.
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- Award ID(s):
- 2114442
- NSF-PAR ID:
- 10451548
- Date Published:
- Journal Name:
- Innovative Smart Grid Technologies
- ISSN:
- 2472-8152
- Page Range / eLocation ID:
- 1-5
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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