Analysis of Semiconductor Based Pre-charge & Cut-off Circuits for 2W/3W Electric Vehicle Battery Management Systems

2021-26-0168

09/22/2021

Features
Event
Symposium on International Automotive Technology
Authors Abstract
Content
As the climate change & CO2 emissions are becoming prime concerns over the globe, Electric Vehicles (EV) are proving to be promising eco-friendly mobility solution. In India too, the transition to electric vehicles is gaining momentum. Batteries constitute a major chunk in the cost of an EV. Battery Management Systems (BMS) are of paramount importance for safety, performance, usability & lifetime of EV. Along with fundamental function of monitoring (cell voltage, pack voltage, pack current, cell/pack temperature), BMS must perform function of controlling (charger/load connect, disconnect, pre-charge) the battery pack in case of failures. In most EVs load capacitance (traction motor controller, charger, DC-DC converter) draws high inrush current from the battery pack. This may not only damage the contactors (connect/disconnect circuits) and other load components but can also affect the lifetime of cells within battery pack. Conventionally, contactor-based cut-off & relay-based pre-charge circuits are present in EVs. However, semiconductor-based cut-off control & pre-charge are gaining acceptance in 2W/3W EV battery packs due to advantages like compactness, robustness against mechanical vibrations & shocks, controllability, competitive cost & functional safety. This paper focuses on various methods of controlling inrush currents using semiconductor-based pre-charge and cut-off circuits. Simulations & practical results of semiconductor-based pre-charge circuits are discussed. It is concluded that, for effective design of BMS for small battery packs, semiconductor-based cut-off & pre-charge techniques will provide an added advantage of improving reliability, safety & controllability.
Meta TagsDetails
DOI
https://doi.org/10.4271/2021-26-0168
Pages
9
Citation
Magar, P., Deshpande, R., Shinde, R., Deo, M. et al., "Analysis of Semiconductor Based Pre-charge & Cut-off Circuits for 2W/3W Electric Vehicle Battery Management Systems," SAE Technical Paper 2021-26-0168, 2021, https://doi.org/10.4271/2021-26-0168.
Additional Details
Publisher
Published
Sep 22, 2021
Product Code
2021-26-0168
Content Type
Technical Paper
Language
English