Battery Loss and Stress Mitigation in a Cascaded H-Bridge Multilevel Inverter for Vehicle Traction Applications by Filter Capacitors
Journal article, 2019

In this paper, two types of filter capacitors of varying capacity, were connected to the battery packs of a cascaded H-Bridge single-star multilevel vehicle traction inverter, and their influence on the battery losses has been analyzed. The battery and capacitor simulation models used are experimentally verified in a down-scaled system. Different capacitor configurations were simulated for four drive cycle scenarios to determine the potentials for the mitigation of current pulse stresses and battery loss reduction with respect to the added weight. By adding capacitors corresponding to a weight of 4% of the initial battery storage, the peak current is reduced by 5%-20%, depending on the operating point from DC to a few kHz, and the battery losses are reduced by 10%. In comparison, it is demonstrated that adding supercapacitors is more beneficial for lower output frequencies, while adding electrolytic capacitors is better for higher output frequencies. Furthermore, the low-order voltage harmonics of the DC-rails between the converter and battery were reduced by 10%-30% for frequencies above 9 kHz, which decreases the potential of electromagnetic disturbances. In addition, during cold battery temperatures, when it is very important to avoid heavy cyclings, the loss reduction using the capacitors was 2.5 times larger than for nominal temperature.

Cascaded

Electrolytic capacitor

Electric vehicle

Supercapacitor

H-bridge

Multilevel converter

Efficiency

Multilevel system

Author

Anton Kersten

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

Oskar Josefsson

Chalmers, Electrical Engineering, Electric Power Engineering

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

Massimo Bongiorno

Chalmers, Electrical Engineering, Electric Power Engineering, Power grids and Components

IEEE Transactions on Transportation Electrification

2332-7782 (eISSN)

Subject Categories

Other Chemical Engineering

Vehicle Engineering

Other Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1109/TTE.2019.2921852

More information

Created

6/25/2019