Overall Design Project
Optimal Design and Operation Strategies of Hyperloop Transportation System
Historically, most transportation systems have been designed considering different boundary conditions and deployment scenarios. Particularly important is the definition of the characteristics of the energy reservoir that a given transportation system is using since this element determines whether the carrier of the system is energy-autonomous or not.
To fix ideas, electric trains (ETs) and electric vehicles (EVs), even if sharing similar propulsion technologies, leverage energy reservoirs of very different characteristics. ETs rely on a quasi-infinite energy reservoir represented by the power grid which, compared to the usual rated powers of trains’ propulsion systems, can be also considered as an infinite power source. Conversely, EVs rely on energy reservoirs (i.e., battery energy storage systems – BESS) characterised by limited gravimetric and volumetric energy and power densities.
Therefore, the design of these two transportation systems is radically different. Indeed, for ETs the energy reservoir does not translate into physical constraints that, on the contrary, need to be be well stated for the design of an EV in order to maximize their travel distance.The two above-mentioned transportation systems merge their characteristics when translated into the Hyperloop concept. Indeed, the Hyperloop presents the same advantages of ETs (high speed, low average energy consumption and CO2 emissions) being an energy-autonomous system.As known, Hyperloop capsules move between pre-determined and well-known trajectories in low-pressure tubes. The pressure in Hyperloop tubes is pumped down to values in the order of 1-10% of normal pressure or below, a condition that reduces drag forces and increases efficiency along with the maximum achievable speed.
This simple operational aspect dramatically reduces the energy needs of a Hyperloop capsule and, conversely, increases its maximum achievable speed. The actual vacuum proof materials enable a low leakage rate of the air. The consequence is that the propulsion system of a Hyperloop capsule may require a substantial amount of power (in the order of several MW per tens of tons of capsule mass) to be extracted from an energy reservoir containing a relatively low amount of energy.For this reason, the optimal sizing of a Hyperloop system is an interesting and non-trivial problem that represents one of the core elements of this research proposal along with the definition, and experimental validation, of optimal control strategies governing the capsule’s navigation system along a controlled environment.