Model-based SW design and Integration of an Electric Vehicle Retrofit Kit with Extended V-Cycle

The automotive industry is moving toward electric vehicles (EVs) solutions. This choice is supported by different aspects such as the decision to manage the environmental crisis, the ban on the sale of ICE vehicles starting from 2035, and economic concession by the government for EVs purchases. However, the transition from ICE vehicles to EVs is not so immediate. In this scenario, the EVERGRIN project, represents a valid solution to facilitate this transition, indeed it consists of involving a retrofit kit able to convert ICE vehicles into fully electric ones. The brain of the retrofit kit is the Vehicle Management Unit (VMU), a control unit that governs the electric powertrain and makes it compatible with the original elements of the vehicle. The focus of the thesis work is the VMU software development for the EVERGRIN project. Since modern vehicles are more and more equipped with electronics, which means an increase in complexity, and to accomplish the automotive safety standard (ISO26262), it becomes necessary to define a systematic procedure for developing the project, that is the Extended V-Cycle. The Extended V-Cycle defines the workflow of the project. The phase 1 consists into defining the functional requirements based on the needs of the customer. In phase 2 the functional requirements are converted into technical specifications following 2 different guidelines: the preliminary study and the user experience; the preliminary study is used to estimate the sizes of the retrofit components and their characteristics while the user experience describes how the vehicle should work in terms of states and transitions. The points 2.1-2.2 regards the construction and the validation in simulation of the Virtual Prototype, which is the complete module of the vehicle, including the control logic. The Virtual Prototype is implemented using the Modular Technical Model (MTM), a template tool built using MATLAB/Simulink. The MTM is a modular architecture made of different modules (HMI, User, Plant, Environment, Control), each one improved by an iterative process of MIL. This modular structure allows to clearly distinguish the control logic module, which is the source of the code that will be downloaded on the VMU at the next stage. In points 2.3-2.4, the control logic is downloaded on a real and powerful VMU (dSpace) and it is tested on the testbench. This constitutes the semi-real prototype, where some parts of the Plant and of the Human Machine Interface are no more models but real components. The result obtained is a source code validated in simulation and on testbench, which governs the interaction with the original vehicle components (pedals, key, handbrake) and the retrofit components (indicators, direction selector, buttons, switches, HV battery, Inverter, e-motor). In future works, the next stages of the Extended V-cycle involve the download of the same control logic on a commercial VMU (phase 3) and repeating the same validation tests on testbench (phase 4) and then move to road test with the real prototype (phase 5).