This study developed generator and rectifier analysis modules to enable sizing for various power outputs, while considering the electrical characteristics and control strategies of the systems. The developed modules were applied to the vertical take-off and landing (VTOL) conceptual design tool, RISPECT+, to perform sizing for the turboelectric propulsion system aircraft. Through this process, it was confirmed that modules effectively account for variations in the efficiency of generators and rectifiers based on mission segments and flight environments. Furthermore, by optimizing the DC-Link voltage between the power generation and propulsion systems, the appropriate DC-Link voltage that minimizes overall electrical losses and maximizes payload was determined. Finally, a comparison of the rotational speeds of the generator and the turboshaft engine was conducted to propose an optimal gear ratio between the two components. This research is expected to contribute to enhancing the reliability of the conceptual design and performance analysis of turboelectric propulsion systems aircraft.