Multilevel Converters for Grid Connected Applications:

Multilevel inverters already gained importance in various industrial applications such as motor drives and grid-connected renewable systems. However, these converters still poses several issues related to component count such as active switches, diodes, dc-link capacitors, and the complex control structures. Capacitor voltage balancing is another issue which is commonly encountered in multilevel inverters.

Research will be conducted with a special focus on reducing the component count and at the same time realising the self-balance of capacitor voltages without the need of complex control algorithms.

Hybrid DC Circuit Breakers:

The medium and high voltage direct current (MVDC & HVDC) power transmission gained greater attention for long distance electric power transmission owing to its advantages over conventional ac systems such as: low cost, lower power losses and asynchronous operation. Multi terminal MVDC transmission also enables the interconnection of various renewable energy sources. However, the major limitation for the usage of multi-terminal MVDC transmission is the protection circuit, i.e. dc circuit breaker (CB). Fault interruption in MVDC lines is a difficult proposition due to the absence of natural current zero crossing unlike conventional ac transmission systems. Hybrid dc circuit breakers have shown better performance, but the usage of surge arrestor and size of energy storage elements play a pivotal role. Additionally, pre-charging of the capacitor is a critical issue in existing hybrid CBs.

Investigation on hybrid medium voltage dc circuit breaker topologies will be conducted to do away with the usage of surge arrestor and the pre-charging of capacitor which enables compact and reliable design of multi-terminal DC transmission systems.

Power Converters for Electric Vehicle Applications:

Will be updated soon...

@ All the pictures are taken from internet.