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This paper proposes a dexel-based virtual prototyping system, which builds a virtual prototype with dexels or rectangular strips of solid. The approach resembles the physical fabrication process of most powder-based rapid prototyping (RP) systems. It simulates an RP process to create a virtual prototype. Colour virtual prototypes may also be fabricated relatively easily. Thus, the designer can perform design validation and accuracy analysis easily in a virtual environment as if using a physical prototype. In addition to numeric quantification of the RP process, the system provides vivid visualisations of the prototype for studying its characteristics. Furthermore, the prototype may be superimposed on the product model, and the areas with dimensional errors beyond design limits may be clearly highlighted for subsequent improvement. The designer may thus analyse and compare the surface texture point-by-point of the prototype with the product design.

With the increase in power electronic solutions for More Electric Aircraft, silicon-carbide MOSFETs are being considered as alternatives to silicon IGBTs in areas such as motor drive systems for primary flight and landing gear actuators. In these high-reliability applications, it's essential that all aspects of the power electronics, including the semiconductor switches, are well understood to ensure correct operation for extended periods. A study on the gate-drive signals of 1200 V SiC MOSFETs in two different prototype power module solutions designed for More Electric Aircraft motor drive applications is presented in this paper. Measurements are recorded for various MOSFET solutions and compared with an IGBT alternative. Furthermore, a dV/dt analysis is presented and the correlation between the gate-drive signals and the dV/dt is shown. Simulation results are validated with test bench measurements and methods for performance improvements are outlined. The data illustrates that the higher switching speed of the SiC devices results in increased transients and higher dV/dt which can impact negatively on the reliability of the system. One method of reducing these effects is by variation of the gate resistance but this may have a negative impact on power dissipation and inverter efficiency as presented in this study.