Design and Development of E-axle as a Retro and OE Fitment Solution for Light Commercial Vehicles Ranging from 1.5 to 5 Ton GVW

Abstract

<div class="section abstract"><div class="htmlview paragraph">The Light commercial vehicle (LCV) is primarily used for the last mile delivery and it hold the volume share of around 61% in the commercial vehicle segment. The last mile delivery services have seen a massive surge after the CoVID 19 pandemic resulting is the increase sale of LCV in last few years and is expected to grow further by 8-11% in the coming years. However, city logistic is also responsible for most pollution and noise in the city. Hence, policymakers are aiming to reduce carbon footprint by promoting the use of Electric vehicle by providing incentive to automakers though schemes like FAME I and FAME II. In order to effectively reduce the carbon footprint within city it is important to increase the use of new electric vehicle and convert the old polluting vehicles to electric. Hence, a retro fitment solution for converting used LCV to electric can help in reducing emission as well as noise pollution. Later the same solution can be offered as OE fitment solution. Though initially CAPEX cost is on higher side mainly due to present price range of Li Ion batteries, the OPEX cost and maintenance cost of electric vehicle is much lower than conventional vehicle which helps in increasing the profit margin and to recover invested CAPEX in certain time frames. However, some initial CAPEX is required.</div><div class="htmlview paragraph">In this paper, the methodology used for design and development of robust E Axle for 1.5T is presented considering first as retro fitment which have potential to convert as OE fitted product. The comprehensive and holistic approach is used to design the product for achieving superior vehicle performance by right sizing of electric drive system and components and by adopting an optimal control strategy for getting target range and lower cost of operation. An optimum and reliable design of E Axle is based on the measured base vehicle on –road performance parameters viz. Max speed, gradeability, vehicle coast down values, differential behavior for torque and speed split during turning, weight distribution during braking etc., off the shelf motor and battery performance and efficiency maps, cooling system, EMI / EMC, NVH requirements. Special emphasis has been given for prediction of transmission error and gear whine for controlling typical NVH signature which can be seen in EV’s. The developed E-axle which consists of a motor integrated to a reduction gearbox can help save space and operation cost apart from other benefits of conventional EVs. Study is conducted for comparison of product costs to control the CAPEX as much as possible. The additional space available resulted due to E Axle configuration can be used to add extra battery capacity for increasing the range of the vehicle or placement of Fuel Cell Engine along with reduced battery pack to give range extension over base. This paper presents experimental results obtained with E Axle based version in comparative manner against base ICE vehicle performance. An integrated 3 in 1 design is under design process as improved version from compactness, maintenance, scalability and improved drive performance point of view.</div></div>