Optimal Design of the Propulsion System of a Hyperloop Capsule

Abstract

In this paper, we focus on the assessment of the optimal design of the propulsion system of an energyautonomous Hyperloop capsule supplied by batteries. The novelty in this paper is to propose a sizing method for this specific transportation system, and answer the question whether the energy and power requirements of the Hyperloop propulsion are compatible with available power-electronics and battery technologies. By knowing the weight of a predetermined payload to be transported along predetermined trajectories, the proposed sizing method minimizes the total number of battery cells that supply the capsule's propulsion and maximizes its performance. The constraints embed numerically-tractable and discrete-time models of the main components of the electrical propulsion system and the battery, along with a kinematic model of the capsule. Although the optimization problem is non-convex due to the adopted discrete-time formulation, its constraints exhibit a good numerical tractability. After having determined multiple solutions, we identify the dominant ones by using specific metrics. These solutions identify propulsion systems characterized by energy reservoirs with an energy capacity in the order of 0.5 MWh and a power rating below 6.25 MW, and enable an energy consumption between 10-50 Wh/km/passenger depending on the length of the trajectory.

Prospects and Challenges of the Hyperloop Transportation System: A Systematic Technology Review

“…4 depicts the Kantrowitz limit, which is a combination of blockage ratio and speed, governed by eqs. (7) and (8). At the speed of sound, a zero blockage is required to avoid choking and prevent the Kantrowitz limit (i.e., infinitely large tube volume).…”

“…The maximum power capability needed is for the acceleration/de-acceleration zones [8]. After the electric propulsors have made the Hyperloop bogie reach the desired service speed, it will eventually require just a fraction of the power to maintain that speed.…”

“…SP-LIMs can regenerate a significant amount of this energy during de-acceleration, if operated as an energy harvester [69]. However, it is important to make the harvesting compatible with the onboard storage system's maximum charging rate [8]. The SP-LIM solution can be configured as a single-sided LIM (Figs.…”

“…Sketch of a conceptual HTS diagram depicting passenger capsules' movement inside a two-way tunnel with two predetermined point-to-point stations. Cruising, acceleration, and braking zones are highlighted (adapted from [8]). native to short-haul flights, where it can promise less travel time and lower fuel consumption per passenger revenue kilometer (RPK).…”

“…A comprehensive subsonic or near-sonic HTS solution has not yet been designed, built, optimized, or tested. Moreover, the research literature demonstrating magnetic levitation and electric propulsion technologies is currently immature for this speed range, where only a few preliminary studies have been presented to address it so far [8], [9], [12]- [14]. According to a 2018 UK innovation report, the critical short-term research and development needs are on the propulsion, levitation, energy storage, and thermal management system [15].…”