Electrical engineering

Physics

Electrode

Isolation transformer

Engineering

Voltage

Parasitic capacitance

Metallurgy

Materials science

Electronic engineering

Silicon carbide

Quantum mechanics

Capacitance

Transformer

Medium voltage (MV) power converters using high voltage (HV) Silicon Carbide (SiC) power semiconductors result in great benefits in weight, size, efficiency and control bandwidth. However, challenges still exist on the components design considering HV insulation and noise immunity requirements in the MV SiC based power converter. A 5-level MMC based transformer-less grid-connected dc/ac converter is developed for 13.8 kV medium voltage grid using 10 kV SiC MOSFETs. The key components, including gate driver with high dv/dt immunity and fast reliable protection, isolated power supply with low parasitic capacitance, voltage/current sensors with high noise immunity, and passives following related insulation standard are provided. A 25 kV dc-link phase-leg is demonstrated, and the experimental results are presented.

Medium Voltage (13.8 kV) Transformer-less Grid-Connected DC/AC Converter Design and Demonstration Using 10 kV SiC MOSFETs