Function Development With an Electric-Machine-in-the-Loop Setup: A Case Study

Konstantin Etzold,Serge Klein,Timm Fahrbach,Stefan Pischinger,Daniel Guse,Marc Klawitter,Rene Scheer,Jakob Andert

doi:10.1109/tte.2019.2952288

Konstantin Etzold, Serge Klein + Show 6 more

Open Access

https://doi.org/10.1109/tte.2019.2952288

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Abstract

In order to reduce automotive development times and costs, particular development tasks are rescheduled to earlier program phases (frontloading) by applying hardware-in-the-loop (HiL) tests. However, there is a shortage of studies considering HiL tests for function developments considering the thermal behavior of electric drives. This article shall be a first step toward closing this gap. A real-time co-simulation of a battery electric vehicle and a driver model are developed and connected to an electric traction machine at a laboratory test bench. A thermal derating function is designed and calibrated at this test setup. In particular, linear derating functions with different gradients are implemented and tested for high load performances during a track race, and the trade-off between energy demand and the lap time is determined. Larger gradients of thermal derating functions lead to shorter lap times and higher energy demands. Thus, for this case study, an increase of the gradient of the thermal derating function by a factor of two results in a lap time improvement of 2.3% and a higher energy demand of 4.7%. The test results demonstrate how HiL setups offer a favorable testing scenario to calibrate thermal derating functions of electrified powertrains in early development phases.

Highlights

F OR automotive development programs of new electric powertrains, investments in time and costs are required to decrease steadily [3]–[8]
The interaction between varying thermal derating functions, the virtual vehicle, and the electric traction machine (ETM) at the test bench are investigated in terms of lap time and the dc energy demand
Thereto, a real-time cosimulation of a battery electric vehicle (BEV) in interaction with a driver model is developed and combined with an ETM installed on a laboratory test bench

Summary

INTRODUCTION

F OR automotive development programs of new electric powertrains, investments in time and costs are required to decrease steadily [3]–[8]. The ETM with power electronics and control units are tested as real components, and the remaining powertrain and the vehicle are simulated. Tested at a HiL setup focusing on the interactions between electric drive and vehicle dynamic behavior Another contribution focuses on different energy storage systems of a parallel hybrid powertrain [28]. There is a particular shortage of studies considering mechanical HiL tests regarding the thermal behavior of electric drives, especially thermal derating functions of electric drives in interaction with the vehicle dynamics. This contribution shall be a first step toward closing this gap.

METHOD – HiL APPROACH

Real-Time Co-Simulations

Laboratory Test Bench Setup With ETM and Power Electronics

Initial Calibration of Thermal Derating Function

RESULTS

CONCLUSION