Industrial Consultancy & Sponsored Research (IC&SR) , IIT Madras
An Appratus And Method For Improving Current Profile Of Medium Voltage Grid Connected Converter
Technology Category/Market
Category- Electronics and Circuits
Industry Classification:
Renewable energy; Electric power generation; Electrical Equipment and Component Manufacturing
Applications:
Renewable Energy Systems Integration; Electric Vehicle (EV) Charging Stations; Smart Grid and Micro grid Applications; Data Centers and Industrial Power Systems; Traction and Marine Applications
Market report:
The global Solid-State Transformer market was valued at USD 100 million in 2024 and is projected to grow to USD 241 million by 2030, registering a CAGR of 15.8%
Problem Statement
- For successful Medium Voltage (MV) grid integration of renewable energy, high power density and efficiency are crucial for minimizing space requirements, maximizing energy utilization, and ensuring grid stability.
- Solid-state transformers use high-frequency transformers for compact size but suffer from power quality issues at low loads.
- Moreover, conventional solutions fail to address high Total Harmonic Distortion (THD) and inefficiencies in medium-voltage grid-connected converters.
- There is a need for a method of hybrid modulation to achieve sinusoidal currents, reducing THD, losses, and enhancing grid stability across load conditions.
Technology
- A hybrid modulation technique enhances current profiles in Cascaded H-Bridge (CHB) based Power Electronic Transformers (PET) for Medium Voltage (MV) grid integration, reducing harmonic distortion and system losses under all loading conditions.
- Combines voltage and current control modulation for CHB cells, ensuring sinusoidal MV grid currents, even at light loads, by utilizing SPWM for initial cells and hysteresis control for the last H-bridge cell.
- Operates at 1.2kV (MVAC), 400V (LVDC), and 200V (LVAC) with a 20kW CHB-based PET prototype, integrating MV grids with high efficiency and minimal harmonic distortion.
- Achieves improved Total Harmonic Distortion (THD), reduces no-load currents by 70%, and eliminates complex voltage balancing with inherent cell voltage regulation using Series Resonant Dual Active Bridge (SR-DAB) converters.
- Suitable for smart grids, EV charging stations, renewable energy systems, and industrial use; validated through hardware testing with reliable sinusoidal output and dynamic performance in active/reactive power transitions.
Key Features/Value Proposition
- The invented technique achieves low THD and sinusoidal current profiles across all conditions. Whereas, conventional approaches fail at light loads.
- The inventions does not require external voltage balancing, unlike traditional multilevel converters that require complex algorithms.
- Decreases no-load current by 70%, and minimizes energy wastage often overlooked by conventional solutions.
- Seamlessly integrates with renewable energy, EV charging, and industrial systems, outperforming less versatile conventional solutions.
- Offers Zero Voltage Switching (ZVS) and Zero Current Switching (ZCS) in the DC-DC stage, enhancing efficiency and device longevity compared to alternatives.
Questions about this Technology?
Contact for Licensing
Research Lab
Prof. Kamalesh Hatua
Department of Electrical Engineering
Intellectual Property
- IITM IDF Ref 2672
- IN 202441043307 Patent Application
Technology Readiness Level
TRL 5
Technology validated in Relevant Environment