With the increase in use of renewable energy and distributed energy sources, use of traditional transformers has increased the complexity of the electrical power grids. In order to overcome this complexity, there is need to adopt newer technologies to ensure better control and more reliable operation of the grid. Transformers are fundamental components of any power distribution system. However, this system does have certain drawbacks such as voltage drop under load, sensitivity to harmonics and performance degradation under system disruptions and overload. The need to cope with these disadvantages is gaining importance as supply of quality power is one of the major issues in today’s scenario. A solid state transformers (SST) is considered a key enabler for power grids, as they provide better control over the system, with high load handling capacity as well as efficient bi-directional power flow.
A SST is capable of easily replacing a conventional transformer in an electrical system. Major applications of SST include locomotive and other traction systems, offshore energy generation systems (wind, tidal or any other source) and smart (power) grids. SSTs are able to deliver power at 400 Hz and can also be used as three-phase power system from a single phase line, which is difficult to obtain from conventional transformers. Depending upon its topologies, SSTs can be classified as:
• AC to AC buck converter
• SST with and without a DC link
• Three-stage SST
The SST market is in its nascent stage. It has huge market potential in the distribution network of power grids. The overall market is expected to grow at a double-digit CAGR between 2012 and 2020.The APAC region is estimated to account for the highest market share by 2020.Smart grids is expected to be the largest segment among the aforementioned applications. The expenditure on smart grids is highest in Asia Pacific, especially in China, which occupies largest share in the region.