Among the many innovations to divert the negative trajectory in the earth’s climate, multiple promising transitions towards addressing our global concerns have been and are under constant research, particularly in the field of transportation. Along this path, it is no wonder why our renowned “fifth mode of transportation” proves to be a breakthrough innovation as it proposes to be inexpensive, unimaginably fast, and significantly powered by environmentally-friendly energy storage systems.
Unlike conventional fuel-driven automobiles, yet similar to our existing hybrid electric vehicles, the proposed concept for the Hyperloop are maglev trains that not only travel at supersonic speeds, but operate and rely on battery systems as the power source to meet its enormous power requirements. Under this concept, the propounded system of batteries not only serve the purpose of powering up the train but also are crucial in powering all sensors, electronics, and controls which will also enable all braking applications for the Hyperloop.
Through the course of unveiling and discovering the various integral, carefully designed elements of our Waterloop Pod in preparation for the upcoming competition, this time around we would like to introduce a short overview of our Power Systems that drive the Pod.
A Description of Waterloo’s Energy Storage System
For the operation of the pod within a pressure-tight enclosure, conventional battery systems failed to meet the demanding needs to ensure its safe operation. To address this challenge, among many investigated options for battery systems such as lead acid batteries, lithium-ion batteries, vanadium redox flow batteries, and flywheel technology batteries. Lithium-Ion Batteries were the most favourable and efficient energy storage system for the Pod as concluded through repeated testing and validation results meeting the important criteria of efficiency, weight, cost, and safety.
Owing to these integral factors, we have chosen a system of 18650 Lithium Ions Batteries. These batteries were chosen for their high capacity and rated discharge, eliminating the need for conventional numerous parallel connections, thus providing a lightweight battery system that is cost-efficient as well. The battery systems function differently under two different configurations: in high voltage configuration, they power the LIM (Linear Induction Motor) during its acceleration phase as well as for its brakes and low-speed systems; in their low voltage configuration, the batteries assist in regulating and powering sensors along with the microcontrollers such as Arduinos and microprocessors such as Raspberry PI Systems.
The employed batteries are constantly monitored by our team for performance by cycle testing, assessed at various discharge rates to determine its expected life cycles, and are examined using overcharging and overcurrent testing methods to dictate its peak values and safety threshold limits on a periodic basis. To ensure the secure operation of these batteries, they are efficiently assembled within a battery management system that helps track any faults or errors in operation strategically along with the support of contractors switches and fail-safe manual switches.
The Supporting Frame for the Batteries
A Battery Management system is vital for any battery system to safeguard the battery cell pack from damage in a vacuum tight pressure container and to report on performance assessments monitoring the efficiency of installed batteries. We are currently conducting profound research and discussions to agree on commissioning a suitable supervision demonstrator design for purposes of achieving a scalable automotive solution for battery management. This Board is capable of supervising circuits from 6s to 96s due to the stackable nature of the BQ79606A-Q1 chip (which is a precision monitor with Integrated Protective Hardware). Similar to battery testing, these boards are being evaluated and are undergoing revised testings for overvoltage, undervoltage (in comparison to manufacturer datasheets and DMMs), passive balancing (to check if the batteries are being balanced to appropriate levels), and thermal stability (testing AUX channels for its accuracy). This multifaceted system efficiently helps to constantly assess and calculate measurements of the state of charge, state of health, voltage, temperature, over-voltage and under-voltage conditions, validating our choice of choosing this system over other options. Working along these lines, we endeavor to achieve the most optimal, sustainable version of the pod, and we have been fervently working with other competing Universities and with our own experienced staff to implement only the best design elements in the Pod.
With such fascinating intricacies of implementation, we made this brief overview on one of the vital components of the Pod to help you decode the Hyperloop’s major design elements as we prepare to unmask our Final Design for the forthcoming Competition!