Medium-voltage (MV) matrix converter topology for wind power conversion using medium-frequency transformer (MFT) isolation

This paper is focused on a new converter topology with medium frequency transformer isolation for medium voltage (MV) wind turbine generator (WTG) power systems. The approach is a high density power conversion, with simultaneous high performance features suitable for next generation wind power systems for both on-shore and off-shore applications. The proposed topology employs 1-phase multi-level AC-AC converters on the utility side and 3×1 matrix converters (3×1 MCs) on the WTG side; interfaced using a medium frequency transformer (MFT). This avoids DC-Link capacitors and/or resonant L-C components in the power flow path thereby improving the power density and reliability. As the system is lightweight, it can possibly be located at the base of the tower itself. This topology can be used in other renewable energy power converters, motor drives, electric locomotives, etc with slight modifications. The validity of the proposed concept has been verified by simulation results and experiment waveforms from a 6.6kVA scaled down laboratory prototype.