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Impact Factor (2025): 6.9
DOI Prefix: 10.47001/IRJIET
Impact Factor (2025): 6.9
DOI Prefix: 10.47001/IRJIET
Vol 10 No 5 (2026): Volume 10, Issue 5, May 2026 | Pages: 808-810
International Research Journal of Innovations in Engineering and Technology
OPEN ACCESS | Research Article | Published Date: 31-05-2026
Solid-State Transformers (SSTs) are emerging as a critical technology for the integration of renewable energy and DC loads in modern distribution grids. Unlike conventional low-frequency transformers, SSTs offer enhanced controllability, voltage regulation, and harmonic isolation. This paper develops a comprehensive three-stage state-space average (SSA) model of an SST, comprising an active rectifier, a high-frequency isolated Dual Active Bridge (DAB) DC-DC converter, and an output voltage source inverter. We derive small-signal linearized models for each stage to design robust PI controllers for DC-link voltage stabilization and AC output regulation. The stability of the interconnected stages is analyzed using eigenvalue trajectories. Simulation results in a 13.8 kV distribution feeder environment demonstrate the efficacy of the proposed controller in maintaining power quality under fluctuating load and generation scenarios.
Solid-State Transformer (SST), State-Space Averaging (SSA), Dual Active Bridge (DAB), distribution systems, small-signal stability.
Preeti Singh, Shailendra Turkar, Gurucharan Mashram, & Preeti Rinhayat. (2026). State-Space Average Model-Based Controller Design for Solid-State Transformers in Modern Distribution Systems. International Research Journal of Innovations in Engineering and Technology - IRJIET, 10(5), 808-810.
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