Replacement of Grid Interface Transformer with Solid State Transformer

In recent years the complexity of the grid systems has grown due to the increased penetration of renewable energy and distributed generation sources. The increased complexity requires new methods to quickly manage the changing sources and loads. This research focuses on one of such technologies, called the Solid State Transformer (SST). In wind energy conversion systems, the fundamental frequency step-up transformer acts as a key interface between the wind turbine and the grid. Recently, there have been efforts to replace this transformer by an advanced power-electronics-based solid-state transformer (SST). This project proposes a configuration that combines the doubly fed induction generator-based wind turbine and SST operation. A SST uses power electronic devices and a high-frequency transformer to achieve isolation and voltage conversion from one level to another. Several SST topologies have been proposed by different research groups, without a clear consensus on which is most suited for grid applications.

In recent years the complexity of the grid systems has grown due to the increased penetration of renewable energy and distributed generation sources. The increased complexity requires new methods to quickly manage the changing sources and loads. This research focuses on one of such technologies, called the Solid State Transformer (SST). In wind energy conversion systems, the fundamental frequency step-up transformer acts as a key interface between the wind turbine and the grid. Recently, there have been efforts to replace this transformer by an advanced power-electronics-based solid-state transformer (SST). This project proposes a configuration that combines the doubly fed induction generator-based wind turbine and SST operation. A SST uses power electronic devices and a high-frequency transformer to achieve isolation and voltage conversion from one level to another. Several SST topologies have been proposed by different research groups, without a clear consensus on which is most suited for grid applications.