The design of a dc generation system is posed as a multi-objective optimization problem which simultaneously designs the generator and the power converter. The proposed design methodology captures the interaction between various system component models and utilizes the system steady state analysis, stability analysis, and disturbance rejection analysis. System mass and power loss are considered as the optimization metrics and minimized. The methodology is demonstrated through the design of a notional dc generation system which contains a Permanent Magnet Synchronous Machine (PMSM), passive rectifier, and a dc-dc converter. To this end, a high fidelity PMSM model, passive rectifier model, semiconductor model and passive component model are developed. The output of optimization is a set of designs forming a Pareto-optimal front. Based on the requirements and the application, a design can be chosen from this set of designs. The methodology is applied to SiC based dc generation system and Si based dc generation system to quantify the advantage of Wide Bandgap (WBG) devices. A prototype SiC based dc generation system is constructed and tested at steady state. Finally a thermal equivalent circuit (TEC) based PMSM thermal model is included in the design paradigm to quantify the impact of the PMSM’s thermal performance to the system design.