Development and Comparison of Monitoring Functions for Electric Vehicles 2013-01-0176
Today functional safety is not an optional part of a vehicle; it is a must that should be taken into account throughout the development process. Fifteen years ago, the first functional safety concepts appeared, and since then technologies have changed in order to fulfill emission standards and client requirements. In parallel, electronic components and vehicle architectures have become increasingly complex in proportion to this evolution. As a result, hazards due to hardware or software failures have increased exponentially, which has led automotive companies to define monitoring concepts and standards.
Over recent years, manufacturers have joined efforts to harmonize their solutions in order to ensure the same level of safety. This has led to the creation of standards such as ISO 26262 or recommendations like E-Gas whose purpose is to give recommendations in terms of the development process and monitoring of a vehicle.
However, the emergence of hybrid and electric vehicles has changed this situation due to the possible vehicle architectures and different possibilities to ensure a solid level of safety.
For this reason, Applus IDIADA has analyzed and developed monitoring functions within the framework of an electric vehicle project. The main objective was to compare different strategies related to the vehicle monitoring in order to determine the most adequate one.
In order to obtain valid and significant results, first analysis and simulations were performed to define the possible failures, related failure modes and expected effects on the vehicle before testing and validating the possible solutions on the vehicle itself.
This paper presents the monitoring algorithms developed to ensure a maximum level of safety regarding component failures (motors, inverters, central drive control ECU) and the test results of each strategy.