Climate change due to global warming are major concerns. Electric vehicles are one of the promising technologies to curb the climate change by reducing CO2 emissions significantly. Electric vehicle component selection is a complex process, which has to fulfil multiple requirements with trade-off between performance & efficiency, efficiency & cost, performance & NVH, packaging & performance etc. In addition, E-drive selection in passenger & commercial vehicle is different due to application difference. Hence, it is a great challenge to select right E-Drive comprising motor, MCU and overall gear ratio to meet EV program constraints and targets.
This study focuses on criterion used for selecting an E-Drive system comprising motor, MCU and overall gear ratio for electric vehicles in commercial and passenger vehicle segments. The automotive market in India is analysed and the most popular vehicles in CV and PV segments with comparable kerb weights have been identified; small commercial vehicle, and compact SUV. The criterion based on vehicle performance, design, cost, and NVH and efficiency requirements. The simulation done to estimate motor torque/power requirements & overall gear ratio meeting the vehicle target and constraints.
Based on the analysis, a comparative matrix consisting of various parameters for commercial and passenger vehicle application is established. The analysed results and established comparative matrix conclude that
- 1
Small commercial vehicles require durable E-drive system with high torque at low speed, deeper gear ratios, low cost and low speed system.
- 2
Passenger vehicles require E-drive system with high power at high speed, nominal gear ratios with optimized powertrain efficiency and a high-speed system.
- 3
Small commercial vehicles need development for separating MCU/inverter from motor, integrated unit not suitable for e-Axle. A separate MCU & motor need to be developed.
- 4
Same existing E-drive system used cannot be interchange in passenger and commercial vehicle applications (similar kerb weight) due to oversizing, operation in low efficiency zones, axle limitation, NVH and integration issues.
Thus E-drive system selection criterion sets guidelines and helps in identifying the parameters for selection E-drive system for commercial and passenger applications