Pareto-optimal solutions for light rail operations: evaluating acceleration strategies to maximise commercial speed

Abstract This study introduces a multi-objective optimisation framework for Electric Multiple Unit (EMU) driving strategies, balancing commercial speed maximisation with the minimisation of wheel-rail wear, energy consumption, and passenger discomfort. Using a weighted sum method, Pareto-optimal solutions are derived across diverse operational scenarios. Energy consumption is analytically modelled to incorporate regenerative braking via an energy recovery factor. Passenger comfort is quantified using a piecewise penalty function, while tribological wear is calculated through multibody simulations of T γ indices. Results show that optimal acceleration strategies vary significantly with operational priorities and are highly sensitive to regenerative braking; higher recovery factors reduce optimal peak acceleration by up to 13.4 % for the Economic Strategy, particularly when the commercial speed priority ranges from 0.2 to 0.5. Passenger comfort emerges as the dominant practical constraint on rapid acceleration, often overriding technical capabilities. This framework offers a comprehensive decision-support tool, demonstrating the interplay between travel time, economic costs, and passenger experience, with regenerative braking enhancing operational flexibility.