Design of a Power Electronic Transformer Structure Based on Multi-Port Converters with Integrated Energy Storage Capability

Abstract :

Power Electronic Transformers (PETs) have emerged as promising alternatives to conventional Line Frequency Transformers (LFTs) in modern power systems. For high-power and high-voltage applications, modular configurations such as Cascaded H-Bridge (CHB) structures are widely recognized as effective PET design solutions. However, existing PET topologies, most commonly based on Dual Active Bridge (DAB) converters, suffer from significant drawbacks, including low-frequency distortion power in DC-link capacitors and degraded performance under fault conditions.

To overcome these limitations, this paper introduces several multi-port converter-based PET architectures. By employing multiple five-port active bridge converters in conjunction with supercapacitors and an advanced control strategy for inter-port power management, the proposed PET achieves enhanced dynamic performance and fault-tolerant operation at both medium-voltage (MV) and low-voltage (LV) levels. Conceptual design and comprehensive simulation studies conducted in Matlab/Simulink confirm the effectiveness and robustness of the proposed topologies.

References:

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