Hafif raylı taşıma sistemleri için SiC çekiş konvertörü: Tasarım metodolojisi ve 500 - 900 VDC, 165 kVA prototipinin geliştirilmesi

Design methodology and development of a 165 kVA, all-silicon carbide (SiC) traction converter for new generation light rail transportation systems (LRTS) have been carried out in this thesis. Electrical, mechanical, and thermal design principles of all-SiC power MOSFET-based traction converter have been described in detail. In order to verify the produced converter, design and implementation of a full-scale physical simulator of an all-SiC traction motor drive for LRTS have been performed. A complete mathematical model of the physical system has been derived to carry out real-time simulations of LRTS, which takes into consideration the actual two quadrant speed versus torque characteristics of a typical traction motor drive. Power losses and thermal performance of SiC power MOSFET modules have been assessed in comparison with those of the alternative Hybrid-IGBT and Si-IGBT modules for various switching frequencies, and their advantages have been considered in view of converter design objectives. This analysis is also repeated for three-level converter topologies in order to visualize the effect of SiC power MOSFETs on converter topology selection. Implementation techniques of the resulting converter power stage, involving the DC and AC laminated busbars, the general layout, and associated cooling system, have been paid special attention. The application method of the space vector PWM technique for operation under variable DC catenary voltages over a wide range has been uniquely described. The associated experimental results were taken on the developed all-SiC power MOSFET-based traction inverter and full-scale physical simulator for LRTS. Very promising results have been obtained on the track of converter design objectives in terms of performance criteria such as very high efficiency, low motor line current total demand distortion, low cooling requirement, relatively high switching frequency, and hence ease of controller implementation.