To maximize power density and dynamics, the supply of electrical and electronics components in electrical assets can go from sinusoidal AC to modulated AC and DC, including voltage and load transients. Hybrid power supply can be a viable option that includes supplying the same component, such as cables by different types of voltage waveforms, and modulated AC and DC. This determines electrical, thermal and mechanical stress profiles that can change significantly with supply voltage and time. This can increase electrothermal and mechanical aging rates (intrinsic and extrinsic aging). As an example, the electric field in defects can incept partial discharges (PD) for one or the other stress conditions, with different PD amplitude and repetition rate. This impacts their harmfulness and the extrinsic aging rate. Life reduction can be dramatic, even if PD activity is discontinuous. The three-pronged approach allows a design that drives the optimized design of insulation systems to maximize their reliability, life, and dimensions/weight, while considering the risk of generating extrinsic aging phenomena.

Evaluation of the Surface Sub-Component of Insulation Systems

The increase of voltage, specific power, and efficiency in electrical assets, especially in electrified transportation and renewable generation, is requiring new electrical insulation system designs and reliability/risk/aging evaluations. This includes the use of power electronics, hybrid supply (AC and modulated AC), higher electric field and operating temperature, and packaging with reduced insulation size. This system focuses on the design of the surface insulation sub-system of components such as spacers, bushings, cable accessories, power electronics boards, PCB, and laminated busbars (LBB). The system is designed for the insulation and connectors/electrodes in a way that the surface partial discharge inception voltage (SPDIV) is not exceeded, under any operation condition and for any level of surface contamination.