Modeling and control of three-phase inverter of swirl turbine

This paper deals with a three-phase inverter controller design for monobloc configuration of small swirl turbine. The aim is an phasing of the system to grid. A simulation design is described which leads to cascade controller with simple structure: lower loop is used for amplitude control and upper loop for phase control. First the highly nonlinear detailed three-phase inverter with switching components and diodes is modeled. Then based on RMS measurement a compensated LTI model is extracted which is used by H-infinity loop-shaping controller synthesis for both controllers design. Lastly design results are verified by simulations applying original three-phase inverter model taking into account high level of disturbances. Resulting system meets with reserve desired behaviour.