Control Board Design for Dual Voltage Source Inverters in Automotive Applications

The work presented in this thesis is part of the European HiEFFICIENT project, which aims to push the boundaries of powertrain inverter design by enhancing energy efficiency, reducing costs, and promoting the adoption of electric mobility and green energy systems. In this context, Ideas & Motion (I&M), the hosting company for this thesis, was responsible for the complete design, development, and prototyping of an automotive-grade modular traction inverter with an integrated control unit. The design of the control board focuses on several key objectives, including fault-tolerant operation, Prognostic Health Management (PHM), an "on-demand" control strategy, and variable switching frequencies up to 50 kHz. This thesis addresses these objectives by developing a prototype board with a modular and flexible architecture, emphasizing both safety and adaptability. The modularity of the design allows the control unit to drive either single or dual Voltage Source Inverters (VSI), providing scalability for different powertrain configurations. It also supports 3-level (3L) inverter topologies by generating up to 18 PWM control signals. To ensure the safety and reliability of the electrical vehicle, the design incorporates several protection mechanisms, such as reverse polarity and battery short-circuit protection, along with redundancy through dual power supply compatibility, ensuring uninterrupted operation in the event of a power source failure. The control board also includes hardware safety logic and an overcurrent detection circuit to enable fast response times and prevent potential system damage. The design further enhances adaptability by interfacing with two motors and supporting both analog and digital position sensors. Additionally, it is equipped to handle multiple communication protocols, including SSI, SENT, CAN, and Ethernet, ensuring robust, high-speed communication and reliable data exchange for control operations and system diagnostics. To improve the board's versatility and integration into various systems, it provides programmable analog and digital inputs, as well as high-side and low-side outputs, enabling seamless interfacing and management of several external auxiliary systems. Simulations of each circuit design were conducted using specific device models to ensure accuracy and full compliance with the application. These simulations allowed for the evaluation of various design solutions, selecting the best approach in terms of performance and cost. Finally, experimental validation was performed on the most critical circuits, demonstrating the good performance of the control board under real-world conditions. This thesis presents a control board design that effectively combines modularity, safety, and adaptability through theoretical design, simulation, and experimental validation. The resulting board implements practical, cost-effective, and high-performance solutions for the design and implementation of traction inverter control boards, addressing the rigorous requirements of modern electric vehicle powertrains.