Performances of Asynchronous Motor within Variable Frequency Drive with Additional Power Source Plugged via Combined Converter

The paper deals with analysis of induction motor operation when it is fed by two sources - one is the frequency converter, the second is a low voltage DC source like photovoltaic panel or fuel cell connected in a special manner via the neutral point of the motor. In this special schematic solution, the switches of frequency converter are controlled by proper algorithm that allows transmitting the energy to the DC link. In the article, the effect of the additional current components on the motor's performances is estimated. Detailed mathematical description of the motor within such combined converter is given, simulation results are shown. Recommendations regarding the values of components providing the best operation are given as well.