Numerical Simulation of Drive Cycles for Formula Electric Vehicle Comparative Powerflow Analysis

Abstract

<div class="section abstract"><div class="htmlview paragraph">This paper proposes a theoretical drive cycle for the competition, considering the battery pack project under design. The vehicle has a non-reversible, double-stage gear train, created without a dynamic investigation. To evaluate the effect on performance, several ratios were analyzed. Dynamic model uses Eksergian’s Equation of Motion to evaluate car equivalent mass (generalized inertia), and external forces acting on the vehicle. The circuit is divided into key locations where the driver is likely to accelerate or brake, based on a predicted behavior. MATLAB ODE Solver executed the numerical integration, evaluating time forward coordinates, creating the drive cycle. Linear gear train results provided data as boundary conditions for a second round of simulations performed with epicyclic gear trains. Model is updated to include their nonlinearity by differential algebraic equation employment with Lagrange multipliers. All data undergoes evaluation to ascertain the mechanical and electrical power requirements. Subsequent analysis aims to comprehend the peak electrical current and energy storage demands of the battery pack, ensuring the car performs in competition as simulated. Whereas reference gear train ratio returns a good time frame, its energy usage surpasses competition rules. Other implemented ratios demonstrated whether an improvement in time frame or an improvement in energy usage. Upgrading one downgrades the other, for instance, speed reduction of 6.0:1 needs 60% more time for a lap than the fastest, but has the lowest energy usage. This behavior justifies epicyclic gear train investigation. Comparison of both models indicate enough evidence that car performance improves with epicyclic gear train appliance. Epicyclic gear train enhances power flow while improving energy management. It can be up to 16 seconds faster (Np=3 v3) than the reference train (9.0:1) and uses nearly the same amount of energy as 6.0:1 ratio.</div></div>