Energy Efficient Torque Allocation Design Emphasis on Payload in a Light-Duty Distributed Drive Electric Vehicle

Pranjal Barman,Brian Azzopardi

doi:10.1109/access.2021.3107421

Pranjal Barman, Brian Azzopardi

Open Access

https://doi.org/10.1109/access.2021.3107421

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Abstract

Light-Duty Electric Vehicle (LDEV) with a distributed drive powertrain provides several potential advantages in terms of flexibility, controllability and responsiveness over conventional powertrains. The precise distribution of driving and braking torque of such configuration is crucially vital for improving the overall performance and efficiency of the vehicles. This paper proposes a new torque allocation (TA) model emphasizing the wheel load variation due to the passenger occupancy payload. A light-duty vehicle model is developed along with the occupancy payload arrangement and a dynamic tire-road friction estimation method for the control system for wheel slip. This proposed TA algorithm uses offline optimization to derive the necessary transmissible torque to the driving wheels. Unlike conventional optimization, it adopts a set of predefined distribution coefficients. Therefore it can execute in a real time platform without high computation power and additional hardware requirements. The efficiency of the model is analyzed using Indian Urban Drive Cycle (IN-UDC). A comparative analysis using a traditional torque allocation model highlights the contributions of this novel torque allocation. The results obtained from various simulations demonstrate the effectiveness of the proposed new TA algorithm.

Highlights

W ITH the ever-increasing fuel crisis, thriving environmental consciousness and adverse effects of climate change, various automotive industries are taking more remarkable initiatives to develop eco-friendly vehicles that reduce the global carbon footprint [1]
All the passengers described above occupancy combinations (from Fig. 1(c)) are evaluated over a continuous time scale
The results show that the torque allocation to each driving wheel for different occupancy combinations are unevenly distributed

Summary

Introduction

W ITH the ever-increasing fuel crisis, thriving environmental consciousness and adverse effects of climate change, various automotive industries are taking more remarkable initiatives to develop eco-friendly vehicles that reduce the global carbon footprint [1]. Distributed drive-train is one kind of powertrain hybridization that has been evolving in recent years This concept becomes widely popular in modern-day research and industrial perspectives. In a distributed drive powertrain configuration, the motors are attached to the wheels independently [2], [3] It offers much better design flexibility, controllability, responsiveness, safety and provides more opportunities to improve the control methodologies [4], [5]. There are two TA strategies categories: (i) the equal torque distribution strategy and (ii) the real-time torque distribution strategy [7] The former strategy dispatched the total torque evenly to each driving wheel. It intuitively represents a scenario in which all the driving wheels work in very similar dynamics and somehow resemble a generic motor.

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Results

Conclusion