Variable Voltage Variable Frequency isolated ac-ac converter

A variable voltage variable frequency single phase ac-ac system using back to back connected single phase VSI is demonstrated. The application of the system could be for solid state transformers. There is a low frequency transformer based galvanic isolation at the load side ac-ac converter. The load side ac-ac system has front end uncontrolled rectifier followed by a VSI.
The system is controlled in closed loop in synchronous reference frame using unbalanced d-q technique.