Electric Powertrain - Standardization of Adaptable Software in Loop System

Motivation With an increase in the complexity involved in modern-day ECUs (Electronic Control Unit), it is very important to verify and validate robustness, functionality, and reliability of ECUs. Till date, Hardware in Loop (HiL) based validation or vehicle level validation is generalized approach used for testing. However, this method requires physical setup, which can incur more cost and time during the development phase. Solution We believe in minimizing the software testing time using Software in Loop (SiL) validation. Creating virtual-ECUs and the plant models is an important step in SiL. We are presenting the modularized and scalable plant models in this paper. Adaptable SiL Solution for EV This paper focuses on the standardization of electric vehicle plant models, which can help users to reduce the software development and software testing time. We created the standardized plant models for following virtual ECUs, which can be used as modular units. • Battery Management System • Motor Control Unit • Vehicle Electronic Control Unit • OBC and DCDC Convertor control Along with the virtual ECUs, we created the scalable plant models of physical systems to be used in the SiL environment. The plant models of battery pack with thermal behavior, motor and invertor along with cooling circuit, vehicle dynamics and AIS test cycles are used as moduler units which are easily scalable. These different plant models can be used with various types of virtual ECUs viz. Type 1 to Type 3. In order to support all types of ECU software development, the middleware tools such as MATLAB/Simulink, Synopsys Silver and ETAS COSYM are used during testing and validation of the software at system level. Outcome Using this test enviroment, battery performance parameters such as state of charge (SOC) estimation, cell voltages and temperatures, passive cell balancing and thermal behaviour can be tested and validated. Motor performance, control and diagnostic algorithm can be functionally validated using these adaptable plant models. Creating virtual CAN communication will provide additional scalability in terms of functional validation and feature testing. This approach of scalable and adaptable plant model is beneficial in regard to cost effectiveness and faster software development and testing.