LiFeP04Battery Modeling and Drive Cycle Loss Evaluation in Cascaded H-Bridge Inverters for Vehicles
Paper in proceedings, 2019

This paper deals with the modeling and parameterization of LiFeP04batteries when used in cascaded H-bridge multilevel inverter drive systems. Since the battery packs are intermittently conducting the motor currents, the battery cells are stressed with a dynamic current waveform containing a substantial amount of low order harmonic components in the range of a couple of kHz. Different battery models like a pure resistive or different RC networks are considered, to determine the battery losses. Measurements of the voltage drop for a pulsed current of variable frequency and magnitude are done to be able to determine the model parameters. The models are then verified against measurements on a battery pack placed in a small scale multilevel inverter operated at 6 different operating point that are representative for the operation of an electrified vehicle. It is shown that the dynamic model agrees very well with the measurements for all operating points analyzed with a maximum deviation of 4 %. The results are also compared with the commonly used resistive model which overestimates the losses with typically around 20 % for the evaluated points. Simulations of 4 full drive cycles are performed where it is stated that the resistive model always shows about 20 % more losses compared to the 3 time constant model.

Author

Oskar Theliander

Anton Kersten

Chalmers, Electrical Engineering, Electric Power Engineering, Electrical Machines and Power Electronics

Manuel Kuder

Universität der Bundeswehr München

Emma Grunditz

Chalmers, Electrical Engineering, Electric Power Engineering, Electrical Machines and Power Electronics

Torbjörn Thiringer

Chalmers, Electrical Engineering, Electric Power Engineering, Electrical Machines and Power Electronics

ITEC 2019 - 2019 IEEE Transportation Electrification Conference and Expo

Vol. June 2019 8790460

2019 IEEE Transportation Electrification Conference and Expo, ITEC 2019
Detroit, USA,

Subject Categories

Applied Mechanics

Vehicle Engineering

Other Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1109/ITEC.2019.8790460

More information

Latest update

1/10/2020