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The aviation industry has been one of the biggest beneficiaries of the major rise in electric power system technology for the past several decades. With more electric aircraft now the industry standard, the new future vision is toward all-electric aircraft, wherein conventional power systems and propulsion sources are electrified. This paper compares and analyzes the Electric Power Systems (EPS) of all-electric vehicles, all-electric ships and more electric aircraft to help predict future development of all-electric aircraft EPS. It is concluded that gravimetric energy density, weight, cost of current battery, and propulsion systems for aircraft are the main limitations preventing the transition to all-electric aircraft. Furthermore, lithium-air batteries show promise for closing the energy density gap between gasoline and batteries. Finally, some recent advancements in small-scale all-electric aircraft development illustrate the bright future of all-electric aircraft.

The penetration level of Plug-in Electric Vehicles (PEVs) is projected to rise in the future, which will lead to significant stress to the power grid due to frequent charging behaviors and their high power demand. While many studies have demonstrated the static stress caused by PEVs for specific scenarios, there is no software platform available for the visualization of the PEVs’ dynamic impacts at the distribution level of the power grid. This paper presents a software prototype that fills this gap. The prototype allows for easy parameter definition, including driving habits, and PEV types. Its back end allows fast integration and data processing for scattered PEV charging over wide areas. The prototype also considers mitigation efforts by providing built-in algorithms for coordinated charging and location planning of charging stations. The prototype is demonstrated on the IEEE 8500 node test case and power systems within Columbus, OH ranging from 81 to 1230 nodes.

More Electric Aircraft (MEA) promise many benefits (e.g., reduced weight, decreased fuel consumption, and high reliability), and their development continues to be the trend. Hybrid Unmanned Aerial Vehicles (UAVs) are an ideal prototype to implement concepts of electrification to aircraft due to their small size and the DC nature of their power systems. This paper proposes an energy optimization method to enhance the energy durability of a UAV. Compared to existing methods for hybrid electric platforms, e.g., ground electric vehicles and electric ships, the proposed method enhances accurate representation of load characteristics and high computation speed, which are critical for aerial vehicles. This is accomplished with a dynamic program containing an inner mixed-integer linear program and a detailed UAV simulation model containing physical circuitry characteristics, reflecting complex and nonlinear behavior within a real system. The efficacy of this method is validated on a realistic UAV system.

With increasing penetration and improving fast charging technologies, Plug-in Electric Vehicles (PEV) exert a disruptive influence on power delivery systems. The impulsive and high-power-density characteristics of PEV make conventional assessment methods of load impact unsuitable. This paper proposes an integrated method to investigate the long-term impact of PEV charging on temporal response and depreciation of grid assets in sub-transmission and distribution grid levels (below 69kV). Compared to conventional methods, the proposed method embeds dynamical system models of grid assets in Time-Series (TS) analysis and captures stochastic charging behavior through Monte-Carlo simulation, promising more robust and accurate assessment. Under the proposed method, the Total Cost of Ownership (TCO) of grid assets formulation is re-established. The results of this paper will enable utilities to quantify the capital and operation cost of grid assets induced under various PEV's penetration level and during any time span of interest.

Electric Vehicle (EV) sales continue to increase, making a preexisting need for updating current infrastructure even more important. Public charging, in particular, fast DC charging technologies can cause stress to the grid, including voltage deviations and increased loading, leading to issues including a degradation of power quality, power equipment loss of life, and brownouts. Literature has shown that distributed generation (DG) can serve as a solution to these stresses to the distribution grid. DG, however, have not been combined with EV charging stations as a method to offset to these stresses. The presented study quantifies the requirements of DG's location and output power in a distribution system with public EV charging stations. This pairing is particularly appealing as it increases generation capacity to meet the needs of EVs in a way which counters grid stress and increases the “green” nature of the grid, furthering the goal of lower emissions. The proposed benefits are demonstrated through three cases in the IEEE-37 bus system.