SmarTrafo is a project funded by Fundação para a Ciênica e a Tecnologia (FCT) within the scope of Projects of development and implementation of research infrastructures included in the national research infrastructures roadmap.
SmarTrafo presented itself as an exploratory project to study and develop applications for Smart Transformers which are a key technological leap for the future of electrical power grids as a means to improve the overall grid power quality and efficiency and reliability. They enable the connection to the grid of Distributed Energy Resources (DERs) as distributed generation units, distributed storage, electrical vehicles and controllable loads (large industrial consumers / set of small domestic consumers), allowing a high level of controllability of the grid voltage and frequency. SmartTrafo differentiates by the use of matrix converters which can convert AC to AC without the inclusion of intermediate energy storage that translate into higher power densities and expected lifetime.
The project committed as outcomes the development and testing of new scalable topologies and controllers to minimize losses and guarantee a Sustainable Grid. In itself this target encompasses several research topics namely: High-frequency transformer sizing methodologies; Usage and development of modern control techniques that are tolerant to the transformer saturation; Modular topologies that can withstand medium-voltage levels of up to 15kV; Stability analysis of microgrids; High efficiency power converter sizing and design;
Combining the advantages of matrix converters with high frequency transformers, the SmarTrafo:
- Will have a reduced volume – when compared to a 50Hz transformer with equivalent current and voltage ratings, the voltage ratings, the developed 2kHz transformer will allow up to 40% volume reduction;
- Will have a modular structure – High Power/High Voltage Transformers may be obtained assembling several modules in parallel, allowing N+1 or N+2 redundancy, thus guaranteeing the transformer reliability;
- Will allow the regulation of the secondary voltage and frequency, playing an active role in the grid, increasing the grid sustainability considering the generation / demand variability;
- Due to its high controllability, it will allow voltage sag and swell mitigation, thus improving Power Quality.
In this scope, in this project: the following actions will be performed:
- Design the High Frequency Transformer;
- Evaluate and develop novel power electronic high frequency converter topologies and novel modulation approaches to be used in the SmarTrafo, guaranteeing the non-saturation of the transformer;
- Design the system controllers to guarantee that the SmarTrafo output voltages are sinusoidal, with user defined frequency (50Hz or 60 Hz) and it is also able to mitigate Power Quality problems (voltage sag, voltage swell, unbalanced AC power supplies, unbalanced loads);
- To build a scaled model laboratory prototype and test it for several operation conditions.
SmarTrafo resulted in several scientific publications as well as multiple Master Thesis which are listed in the Publications tab. A description of the main accomplishments of this project is detailed in Development tab.